Efficiency of Tinospora crispa against Culex quinquefasciatus larva

Abstract

Tinospora crispa stem aqueous extractions for various time durations were determined regarding their total phenolic content and their larvicidal abilities. The results revealed that the total phenolic content in 1-, 3-, 5-, 10-, and 24-h extracts were 8.26, 8.43, 13.57, 12.52, and 12.43 mg/g gallic acid equivalent, respectively. The 5-h extract of T. crispa was evaluated against Culex quinquefasciatus mosquito larva in concentrations 3.125, 6.25, 12.5, and 25 mg/l, by determining the lethal concentration (LC) within 24 h and by histopathological analysis. The 24-h LC₅₀ and LC₉₀ values were 16.95 and 30.12 mg/l, respectively. The histopathological lesions after exposure to 50% of the 24-h LC₅₀ were observed primarily in the midgut of the larva. The lesions observed were for the example epithelial cells lifting from the basement membrane, cell elongation protruding into the lumen, brush border disrupting with absent microvilli, and vesicle appearance. The present study indicated that the aqueous extract of this herb may have a suitable property for a larvicidal natural product and may replace harmful chemical pesticides.

Spotlight on… Gabriella Campadelli-Fiume

Biographical Summary

My first education was in biochemical pathogenesis of disease at the University of Bologna, Italy, University College, London and Max Planck institute, Heidelberg. I entered Virology in 1972 in the University of Bologna, where I still work. I am the head of the molecular virology laboratory in the Department of Experimental Medicine, University of Bologna. The focus of my research is on the molecular mechanisms of herpes simplex virus (HSV) entry into the cell, and on how to modify the HSV tropism in order to generate highly cancer-specific, highly safe, yet fully virulent oncolytic herpesviruses. Academically, I fostered the integration of the Italian Virology in the European Virology.

Correction to: MiR-760 suppresses non-small cell lung cancer proliferation and metastasis by targeting ROS1

In the original article the authors list and the credit to the corresponding authors were not complete.

Characterization and quality assessment of recycled post-consumption poly(ethylene terephthalate) (PET)

Abstract

In the present study, the recycled post-consumption polyethylene terephthalate (PET) flakes were investigated as possible raw materials for the production of food packaging. After heating at 220 °C for 1 h, a steaming stage was conducted as a control test to assess the quality of the product. Different samples were characterized by ¹H-NMR, FT-IR, DSC/TGA analysis, viscosity index (VI), and trace metals analysis. The results showed that the recycled post-consumed PET flakes' properties were generally conform to the standard norms of PET except the color of some flakes turned to yellow. Subsequently, a complementary study was undertaken to assess whether the material could be possibly reused for food packaging. For this purpose, rheological, thermal, and mechanical characterizations were performed. The results of the comparative study between the virgin and the recycled PET flakes concluded that the PET recycling affected the rheological properties but did not have any significant effect on their thermal and mechanical characteristics. Hence, it was deduced that the post-consumed PET flakes could be reused as a packaging material except food products.

Effect of alumina nano additives into biodiesel-diesel blends on the combustion performance and emission characteristics of a diesel engine with exhaust gas recirculation

Abstract

In the present study, the combined effect of alumina nanoparticles into the Calophyllum inophyllum biodiesel blend and exhaust gas recirculation on the combustion, performance, and emission characteristics of a diesel engine was investigated. The alumina (Al₂O₃) nanoparticles with the mass fraction of 40 ppm were dispersed into the C. inophyllum biodiesel blend (20% of C. inophyllum biodiesel + 80% of diesel (CIB20)) by the ultrasonication process. Further, the exhaust gas recirculation was adopted to control the oxides of nitrogen (NOx) emissions of a diesel engine. The experiments were conducted on a single cylinder diesel engine with the diesel, CIB20, 20% of C. inophyllum biodiesel + 80% of diesel + 40 ppm Al₂O₃ nanoparticles (CIB20ANP40), CIB20 + 20% exhaust gas recirculation (EGR), and CIB20ANP40 + 20% EGR fuel samples at different load conditions. The results reveal that brake thermal efficiency of CIB20ANP40 fuel increased by 5.04 and 7.71% compared to the CIB20 and CIB20ANP40 + 20% EGR fuels, respectively. The addition of alumina nanoparticles to the CIB20 fuel, CO, and hydrocarbon (HC) emissions were was reduced compared to the CIB20 fuel. The smoke opacity was decreased with the addition of alumina nanoparticles to the CIB20 fuel by 7.3% compared to the CIB20 fuel. The NOx emissions for the CIB20ANP40 + 20% EGR fuel was decreased by 36.84, 31.53, and 17.67% compared to the CIB20, CIB20ANP40, and CIB20 + 20% EGR fuel samples at full load condition.

The response of zooplankton communities to the 2016 extreme hydrological cycle in floodplain lakes connected to the Yangtze River in China

Abstract

The Huayanghe Lakes play an important role in the Yangtze floodplain in China and had extremely high water levels during the summer of 2016. Monitoring data was collected in an effort to understand the impact of this change on the crustacean zooplankton composition and abundance and the biomass variation in the Huayanghe Lakes between a regular hydrological cycle (RHC) and an extreme hydrological cycle (EHC). The crustacean zooplankton community composition, abundance, and biomass in the floodplain lakes were markedly affected by the water-level disturbance. The number of species was lower in the RHC, but the mean density and biomass decreased from 93.84 ± 13.29 ind./L and 6.11 ± 0.89 mg/L, respectively, in the RHC to 66.62 ± 10.88 ind./L and 1.22 ± 0.26 mg/L, respectively, in the EHC. Pearson correlations and redundancy analyses revealed the environmental factors with the most significant impact on the crustacean zooplankton community differed between the RHC and EHC cycles. Little previous information exists on the zooplankton in these lakes, and the present study provides data on the zooplankton composition, abundance, and biomass, both at baseline and in response to hydrological changes.

Effects of multiple environmental factors on the growth and extracellular organic matter production of Microcystis aeruginosa : a central composite design response surface model

Abstract

In this study, statistically designed experiments using response surface methodology were conducted on Microcystis aeruginosa. A central composite design response surface model was established to investigate the multiple effects of various physical and chemical factors (total nitrogen, total phosphorus, temperature, and light intensity) on algal density and extracellular organic matter. The results of the experiments reveal that nitrate and phosphate had significant interactive effects on algal density, both iron and light intensity had synergic effects on the production of microcystins (MC-LR) and extracellular polysaccharides (EPS), and light intensity and nitrite had clear interactive effects on EPS release. Results did not show significant interactive effects on extracellular dissolved organic carbon (DOC) production. The contribution of extracellular dissolved organic matter of Microcystis aeruginosa during the logarithmic phase was further identified using a three-dimensional excitation emission matrix (3-DEEM). This study contributes to our theoretical knowledge of the prediction and analysis of M. aeruginosa growth and extracellular organic matter production.

Leaf decomposition and nutrient release of three tree species in the hydro-fluctuation zone of the Three Gorges Dam Reservoir, China

Abstract

In order to understand the effect of submergence on nutrient release of the reforested tree leaves and assess the environmental risk of leaf decomposition under submergence, the mass loss and nutrient release rates of three reforestation tree species, Taxodium ascendens Brongn, Taxodium distichum (L.) Rich., and Salix matsudana Koidz., at different elevation in the hydro-fluctuation zone of the Three Gorges Dam Reservoir (TGDR) region were tested in situ. Results showed that the initial macroelement contents of the leaves of the three tree species varied among different elevations due to different submergence stresses. All foliar mass loss rates of the three tree species at 165 m a.s.l. were significantly higher than that at 175 m a.s.l. (except that of S. matsudana at 165 m a.s.l.), after 179 days of incubation commenced September 20. After 138 days of incubation commenced October 5, the foliar mass loss rates of the three tree species at 170 m a.s.l. were significantly higher than that at 175 m a.s.l. Moreover, the leaf mass loss rates of S. matsudana were higher than the other two species when compared at the same elevation of the same incubation period. In addition, foliar release rates of N and Ca in T. ascendens, C, N, and Ca in T. distichum as well as Ca in S. matsudana at 165 m a.s.l. after 179 days of incubation and at 170 m a.s.l. after 138 days of incubation were significantly higher than that at 175 m a.s.l., respectively. Leaf mass loss rates of T. ascendens were significantly correlated with its initial leaf K, Ca, and Mg contents. In contrast, leaf mass loss rates of T. distichum had significant correlations with the initial leaf P and K contents, as well as C/P and N/P ratios. However, the mass loss rates of S. matsudana significantly correlated with initial leaf N, P, and Ca contents and C/N, C/P, and N/P ratios. Foliar nutrient release rates, especially the foliar release of C, N, and P of the three tree species, had significant correlations with initial leaf C/P and N/P ratios. Our results suggested that submergence facilitated the decomposition and nutrient release rates of the leaves of the three woody species, especially the broad leaves of S. matsudana, which may potentially cause secondary pollution to the water body of the TGDR. Thus, we suggested that a sustainable harvest of leaves of the reforested forest stands prior to submergence should be considered in the hydro-fluctuation zone so as to protect the water quality of the TGDR.

Differentiation and induced sensorial alteration of the coronal organ in the asexual life of a tunicate

Abstract

Tunicates, the sister group of vertebrates, possess a mechanoreceptor organ, the coronal organ, which is considered the best candidate to address the controversial issue of vertebrate hair cell evolution. The organ, located at the base of the oral siphon, controls the flow of seawater into the organism and can drive the "squirting" reaction, i.e., the rapid body muscle contraction used to eject dangerous particles during filtration. Coronal sensory cells are secondary mechanoreceptors and share morphological, developmental and molecular traits with vertebrate hair cells. In the colonial tunicate Botryllus schlosseri, we described coronal organ differentiation during asexual development. Moreover, we showed that the ototoxic aminoglycoside gentamicin caused morphological and mechanosensorial impairment in coronal cells. Finally, fenofibrate had a strong protective effect on coronal sensory cells due to gentamicin-induced toxicity, as occurs in vertebrate hair cells. Our results reinforce the hypothesis of homology between vertebrate hair cells and tunicate coronal sensory cells.

Can strain dependent inhibition of cross-bridge binding explain shifts in optimum muscle length?

Abstract

Skeletal muscle force is generated by cross-bridge interactions between the overlapping contractile proteins, actin and myosin. The geometry of this overlap gives us the force-length relationship in which maximum isometric force is generated at an intermediate, optimum, length. However, the force-length relationship is not constant; optimum length increases with decreasing muscle activation. This effect is not predicted from actin-myosin overlap. Here we present evidence that this activation-dependent shift in optimum length may be due to series compliance within muscles. As muscles generate force during fixed-end contractions, fibers shorten against series compliance until forces equilibrate and they become isometric. Shortening against series-compliance is proportional to activation, and creates conditions under which shortening-induced force depression may suppress full force development. Greater shortening will result in greater force depression. Hence, optimum length may decrease as activation rises due to greater fiber shortening. We discuss explanations of such history dependence, giving a review of previously proposed processes and suggesting a novel mechanistic explanation for the most likely candidate process based on tropomyosin kinetics. We suggest this mechanism could change the relationship between actin-myosin overlap and cross-bridge binding potential, not only depressing force at any given length, but also altering the relationship between force and length. This would have major consequences for our understanding of in vivo muscle performance.

Town and country reptiles: A review of reptilian responses to urbanization

Abstract

The majority of the world population is now inhabiting urban areas, and with staggering population growth urbanization is also increasing. While work studying the effects of changing landscapes and specific urban pressures on wildlife is beginning to amass, the majority of this work focuses on avian or mammalian species. However, the effects of urbanization likely vary substantially across taxonomic groups due to differences in habitat requirements and life history. The current paper aims first to broaden the review of urban effects across reptilian species; second, to summarize the responses of reptilian fauna to specific urban features; and third, to assess the directionality of individual and population level responses to urbanization in reptile species. Based on our findings, urban research in reptilian taxa is lacking in the following areas: 1) investigating interactive or additive urban factors 2) measuring multiple morphological, behavioral and physiological endpoints within an animal, 3) linking individual to population-level responses, and 4) testing genetic/genomic differences across an urban environment as evidence for selective pressures.

Detecting Bias in Large-Scale Comparative Analyses: Methods for Expanding the Scope of Hypothesis-Testing with HormoneBase

Synopsis

To address large-scale questions in evolutionary biology, the compilation of data from a variety of sources is often required. This is a major challenge in the development of databases in organismal biology. Here, we describe the procedure we used to reconstruct the phylogeny of the 474 species represented in HormoneBase, including fish, amphibians, mammals, birds, and reptiles. We also provide the methodology used to compile vertebrate environmental, life history, and metabolic rate data for use in conjunction with the HormoneBase database to test hypotheses of the evolution of steroid hormone traits. We then report a series of analyses using these data to determine the extent to which field measures of circulating hormones and associated life history data exhibit taxonomic and geographic bias. By providing a detailed description of the approaches used to compile and evaluate these data and identifying potential biases in the collection of these data, we hope to make the HormoneBase database a more broadly useful resource for the scientific community to address a diversity of comparative questions.

The evolutionary endocrinology of circulating glucocorticoids in free-living vertebrates: recent advances and future directions across scales of study

Synopsis

Circulating glucocorticoid hormone concentrations are dynamic, flexible, and promote adaptive responses following perturbations in an animal's environment. As a result, circulating glucocorticoid levels are thought to shape fitness and have been suggested to be a key trait for predicting how species will cope with novel environmental change. Nevertheless, the factors that shape variation in glucocorticoid-mediated coping mechanisms remain unclear because the evolutionary underpinnings of the function and regulation of these hormones are poorly understood. Here, I summarize recent advances in our understanding of the evolution of circulating glucocorticoids, which have included (i) longitudinal studies exploring microevolutionary processes that shape within- and between-individual variation in glucocorticoids, (ii) interspecific comparative studies highlighting macro-evolutionary patterns of among-species variation in glucocorticoids, and (iii) intraspecific comparative studies which help to disentangle the relative roles of environment, life-history and behaviour in shaping among-population variation in glucocorticoids. Important avenues for future research will include exploring how natural selection may act on different components of the hypothalamus-pituitary-adrenal axis, characterizing patterns of phenotypic plasticity in circulating glucocorticoids across populations and species, as well as exploring how microevolutionary processes differ across taxa or gradients of environmental conditions.

Designing for Broad Understanding of Science

Abstract

With the acceleration and increasing complexity of macro-scale problems such as climate change, the need for scientists to ensure that their work is understood has become urgent. As citizens and recipients of public funds for research, scientists have an obligation to communicate their findings in ways many people can understand. However, developing translations that are broadly accessible without being "dumbed down" can be challenging. Fortunately, tenets of visual literacy, combined with narrative methods, can help to convey scientific knowledge with fidelity, while sustaining viewers' interest. Here we outline strategies for such translating, with an emphasis on visual approaches. Among the examples is an innovative, NSF-funded professional development initiative in which National Park rangers use scientists' imagery to create compelling explanations for the visiting public. Thoughtful visualizations based on interpretive images, motion pictures, 3D animations and augmented, immersive experiences complement the impact of the natural resource and enhance the role of the park ranger. The visualizations become scaffolds for participatory exchanges in which the ranger transcends the traditional roles of information-holder and presenter, to facilitate provocative conversations that provide members of the public with enjoyable experiences and well-founded bases for reflection and ultimately understanding. The process of generating the supporting visualizations benefits from partnerships with design professionals, who develop opportunities for engaging the public by translating important scientific findings and messages in compelling and memorable ways.

Biodiversity and Extinction of Hawaiian Land Snails: How Many are Left Now and What Must We Do To Conserve Them – A Reply to Solem (1990)

Abstract

Synopsis: Pacific islands, with their incredible biodiversity, are our finest natural laboratories for evolutionary, ecological and cultural studies. Nowhere, in relation to land area, does land snail diversity reach that of the Pacific islands, with more than 6,000 species, most of which are single island endemics. Unfortunately, land snails are the most imperiled group with the most recorded extinctions since the 1500s, and Pacific island snails make up the majority of those extinctions. In 1990, Dr. Alan Solem, a well renowned malacologist, with expertise in Pacific island land snails, posthumously published a plea to save the remaining Hawaiian land snails before they vanish forever. Now, more than 25 years later, we have finally begun to make inroads into answering the questions "How many Hawaiian land snails remain?" and "What will we need to save them?". Here we provide a belated reply to Solem (1990) and address these questions about Hawaiian land snails. We conclude by building on the actions suggested by Solem and that we feel are still needed to realize his hope of conserving Hawaii's remaining land snails specifically, but also our hope of conserving invertebrates more broadly.

The kingdom of the blind: disentangling fundamental drivers in the evolution of eye loss

Abstract

Light is a fundamentally important biological cue used by almost every animal on earth, to maintain daily rhythms, navigate, forage, find mates or avoid predators. But an enormous number of species live in darkness: in subterranean caves, deep oceans, underground burrows, and within parasitic host bodies, and the loss of eyes appears consistently across these ecosystems. However, the evolutionary mechanisms that lead to the reduction of the visual system remain the subject of great interest and debate more than 150 years after Darwin tackled the issue. Studies of model taxa have discovered significant roles for natural selection, neutral evolution and pleiotropy, but the interplay between them remains unclear. To nail down unifying concepts surrounding the evolution of eye loss, we must embrace the enormous range of affected animals and habitats. The fine developmental details of model systems such as the Mexican cave tetra Astyanax mexicanus have transformed and enriched the field, but these should be complemented by wider studies to identify truly overarching patterns that apply throughout animals. Here, the major evolutionary drivers are placed within a conceptual cost-benefit framework that incorporates the fundamental constraints and forces that influence evolution in the dark. Major physiological, ecological and environmental factors are considered within the context of this framework, which appears faithful to observed patterns in deep-sea and cavernicolous animals. To test evolutionary hypotheses, a comparative phylogenetic approach is recommended, with the goal of studying large groups exhibiting repeated reduction, and then comparing these across habitats, taxa, and lifestyles. Currently, developmental and physiological methods cannot feasibly be used on such large scales, but penetrative imaging techniques could provide detailed morphological data non-invasively and economically for large numbers of species. Comprehensive structural datasets can then be contextualised phylogenetically to examine recurrent trends and associations, and to reconstruct character histories through multiple independent transitions into darkness. By assessing these evolutionary trajectories within an energetic cost-benefit framework, the relationships between fundamental influences can be inferred and compared across different biological and physical parameters. However, substantial numbers of biological and environmental factors affect the evolutionary trajectory of loss, and it is critical that researchers make fair and reasonable comparisons between objectively similar groups.

Body stiffness and damping depend sensitively on the timing of muscle activation in lampreys

Synopsis

Unlike most manmade machines, animals move through their world using flexible bodies and appendages, which bend due to internal muscle and body forces, but also due to forces from the environment. Fishes in particular must cope with fluid dynamic forces that not only resist their overall swimming movements but also may have unsteady flow patterns, vortices, and turbulence, many of which occur more rapidly than what the nervous system can process. Has natural selection led to mechanical properties of fish bodies and their component tissues that can respond very quickly to environmental perturbations? Here, we focus on the mechanical properties of isolated muscle tissue and of the entire intact body in the silver lamprey, Ichthyomyzon unicuspis. We developed two modified work loop protocols to determine the effect of small perturbations on the whole body and on isolated segments of muscle as a function of muscle activation and phase within the swimming cycle. First, we examined how the mechanical properties of the whole lamprey body change depending on the timing of muscle activity. Relative to passive muscle, muscle activation can modulate the effective stiffness by about two-fold and modulate the effective damping by more than 10-fold depending on the activation phase. Next, we performed a standard work loop test on small sections of axial musculature while adding low-amplitude sinusoidal perturbations at specific frequencies. We modeled the data using a new system identification technique based on time-periodic system analysis and harmonic transfer functions and used the resulting models to predict muscle function under novel conditions. We found that the effective stiffness and damping of muscle varies during the swimming cycle, and that the timing of activation can alter both the magnitude and timing of peak stiffness and damping. Moreover, the response of the isolated muscle was highly nonlinear and length dependent, but the body's response was much more linear. We applied the resulting harmonic transfer functions from our experiments to explore the effect of pairs of antagonistic muscles. The results suggest that when muscles work antagonistically, the nonlinearities present in either muscle segment alone are reduced. Together, these results begin to provide an integrative understanding of how activation timing can tune the mechanical response properties of muscles, enabling fish to swim effectively in their complex and unpredictable environment.

Myofascial loads can occur without fascicle length changes

Abstract

Many studies have shown that connective tissue linkages can transmit force between synergistic muscles and that such force transmission depends on the position of these muscles relative to each other and on properties of their intermuscular connective tissues. Moving neighboring muscles has been reported to cause longitudinal deformations within passive muscles held at a constant muscle-tendon unit (MTU) length (e.g. soleus, SO), but muscle forces were not directly measured. Deformations do not provide a direct measure of the force transmitted between muscles. We combined two different muscle preparations to assess whether myofascial loads exerted by neighboring muscles result in length changes of SO fascicles. We investigated the effects of proximal MTU length changes of two-joint gastrocnemius (GA) and plantaris (PL) muscles on the fascicle length of the one-joint SO muscle within (1) an intact muscle compartment and (2) a disrupted compartment that allowed measurements of fascicle length and distal tendon force of SO simultaneously. SO muscle bellies of Wistar rats (n=5) were implanted with sonomicrometry crystals. In three animals, connectivity between SO and GA+PL was enhanced. Measurements were performed before and during maximal excitation of all plantar flexor muscles. In both setups, MTU length of GA+PL did not affect the length of SO fascicles, neither during passive nor active conditions. However, lengthening the MTU of GA+PL increased distal tendon force of SO by 43.3-97.8% (p < 0.001) and 27.5-182.6% (p < 0.001), respectively. This indicates that substantial myofascial force transmission between SO and synergistic muscle can occur via a connective tissue network running parallel to the series of SO sarcomeres without substantial length changes of SO fascicles.

Narrative and “anti-narrative” in science: How scientists tell stories, and don’t

Synopsis

Narratives are common to all branches of science, not only to the humanities. Scientists tell stories about how the things we study work, develop, and evolve, and about how we come to be interested in them. Here I add a third domain (Secularity) to Gould's two "non-overlapping magisteria" of Science and Religion, and I review previous work on the parallels in elements between story-telling in literature and science. The stories of each domain have different criteria for judging them valid or useful. In science, especially historical sciences such as biology and geology, particular scientific methods and approaches both structure and test our narratives. Relying on the narrative assumptions of how certain processes, such as natural selection, are supposed to work is treacherous unless they are tested by appropriate historical patterns, such as phylogeny, and rooted in the process of natural mechanisms. The structure of scientific explanation seen in peer-reviewed papers and grant proposals obscures true narrative within a formulaic sequence of "question, methods, materials" and so on that is quite different from the classic narrative of folk-tales and novels, producing an "anti-narrative" that must be "un-learned" before it can be communicated to non-scientists. By adopting some of the techniques of classic story-telling, scientists can become more effective in making our ideas clear, educating the public, and even attracting funding.

The Mitochondrial Basis for Adaptive Variation in Aerobic Performance in High-Altitude Deer Mice

Synopsis

Mitochondria play a central role in aerobic performance. Studies aimed at elucidating how evolved variation in mitochondrial physiology contributes to adaptive variation in aerobic performance can therefore provide a unique and powerful lens to understanding the evolution of complex physiological traits. Here, we review our ongoing work on the importance of changes in mitochondrial quantity and quality to adaptive variation in aerobic performance in high-altitude deer mice. Whole-organism aerobic capacity in hypoxia (VO₂max) increases in response to hypoxia acclimation in this species, but high-altitude populations have evolved consistently greater VO₂max than populations from low altitude. The evolved increase in VO₂max in highlanders is associated with an evolved increase in the respiratory capacity of the gastrocnemius muscle. This appears to result from highlanders having more mitochondria in this tissue, attributed to a higher proportional abundance of oxidative fibre-types and a greater mitochondrial volume density within oxidative fibres. The latter is primarily caused by an over-abundance of subsarcolemmal mitochondria in high-altitude mice, which is likely advantageous for mitochondrial O₂ supply because more mitochondria are situated adjacent to the cell membrane and close to capillaries. Evolved changes in gastrocnemius phenotype appear to be underpinned by population differences in the expression of genes involved in energy metabolism, muscle development, and vascular development. Hypoxia acclimation has relatively little effect on respiratory capacity of the gastrocnemius, but it increases respiratory capacity of the diaphragm. However, the mechanisms responsible for this increase differ between populations: lowlanders appear to adjust mitochondrial quantity and quality (i.e., increases in citrate synthase [CS] activity, and mitochondrial respiration relative to CS activity) and they exhibit higher rates of mitochondrial release of reactive oxygen species (ROS), whereas highlanders only increase mitochondrial quantity in response to hypoxia acclimation. In contrast to the variation in skeletal muscles, the respiratory capacity of cardiac muscle does not appear to be affected by hypoxia acclimation and varies little between populations. Therefore, evolved changes in mitochondrial quantity and quality make important tissue-specific contributions to adaptive variation in aerobic performance in high-altitude deer mice.

Shape, size, and structure affect obliquely striated muscle function in squid

Abstract

Hollow, cylindrical body plans and obliquely striated muscles are characteristic of soft-bodied invertebrates, and both affect the biomechanics of movement in these diverse animals. We highlight two different aspects of functional heterogeneity in obliquely striated muscles, one driven by animal shape and size and the other by the intrinsic mechanical properties of the fibers. First, we show how a hollow, cylindrical shape in the mantle of cephalopod molluscs causes a significant difference in muscle strain (defined as the change in length divided by resting length) across the mantle wall, and describe the implications of such "transmural gradients of strain" for the length-tension relationship of the obliquely striated muscles that power movements in these animals. We show that transmural gradients of strain increase in magnitude as mantle wall proportions change during ontogeny, with the relatively thin mantle walls of newly hatched squid experiencing significantly smaller differences in strain than the thicker mantle walls of adults. Second, we describe how the length-tension relationship of obliquely striated mantle muscles varies with position to accommodate the transmural gradient of strain, with the result that circular muscle fibers near the inner and outer surfaces of the mantle are predicted to produce similar force during mantle contraction. The factors that affect the length-tension relationship in obliquely striated muscles are unknown, and thus we have not yet identified the mechanism(s) responsible for the transmural shift in the length-tension properties of the mantle circular fibers. We have, however, developed a mathematical model that predicts small changes in the oblique striation angle (which varies from 4 to 12° in adult squid) have a significant effect on the shape of the length-tension relationship, with lower angles predicted to result in a broader length-tension curve.

HIPEC: HOPE or HYPE in the fight against advanced ovarian cancer?

Reply to the Letter to the Editor "Reporting of HRQOL results from the PALOMA-2 trial: unfounded conclusions due to highly biased analyses" by T. Kaiser, et al.

Impact of age on the efficacy of oxaliplatin in the preoperative chemoradiotherapy and adjuvant chemotherapy of rectal cancer: A post hoc analysis of the CAO/ARO/AIO-04 phase 3 trial

Abstract

Background

The German rectal cancer trial CAO/ARO/AIO-04 has shown a significant benefit in 3-year disease-free survival (DFS) of adding oxaliplatin to a standard preoperative 5-fluorouracil-based chemoradiotherapy (CRT) and adjuvant chemotherapy in patients with locally advanced rectal cancer. The use of oxaliplatin as adjuvant treatment in elderly patients with colon cancer is controversial . We therefore investigated the impact of age on clinical outcome in the CAO/ARO/AIO-04 phase 3 trial.

Patients and Methods

We performed a post hoc analysis of the CAO/ARO/AIO-04 phase 3 trial evaluating primary and secondary endpoints according to age. Patient and tumor characteristics, adverse events grades of 3-4, dose intensities as well as survival and recurrence data were analyzed in three specified age groups (<60, 60-70, and ≥70 years). The influence of age as a continuous variable on DFS was modeled using a subpopulation treatment effect pattern plot (STEPP) analysis.

Results

A total of 1,232 patients were evaluable. With the exception of ECOG status (p < 0.001), no differences in patient and tumor characteristics were noticed between age groups. Likewise, toxicity pattern, dose intensities of CRT and surgical results were similar in all age groups. After a median follow-up of 50 months, in patients aged <60 years a significant benefit of adding oxaliplatin to 5-FU-based CRT and adjuvant chemotherapy was observed for local (p = 0.013) and systemic recurrences (p = 0.023), DFS (p = 0.011) and even overall survival (OS; p = 0.044. The STEPP analysis revealed improved hazard ratios for DFS in patients aged 40-70 years compared with elderly patients treated with oxaliplatin.

Conclusion

The addition of oxaliplatin significantly improved DFS and OS in younger patients aged <60 years with advanced rectal cancer. Patients aged ≥70 years had no benefit.

Clinical Trials Number

NCT00349076

Anti-EGFR therapy in oesophagogastric cancer: precise but not enough

Reporting of HRQOL results from the PALOMA-2 trial: unfounded conclusions due to highly biased analyses

Mediastinal lymph node clearance and anti-PD-1 induction in resected NSCLC

Non-rigid registration of 3D ultrasound for neurosurgery using automatic feature detection and matching

Abstract

Purpose

The brain undergoes significant structural change over the course of neurosurgery, including highly nonlinear deformation and resection. It can be informative to recover the spatial mapping between structures identified in preoperative surgical planning and the intraoperative state of the brain. We present a novel feature-based method for achieving robust, fully automatic deformable registration of intraoperative neurosurgical ultrasound images.

Methods

A sparse set of local image feature correspondences is first estimated between ultrasound image pairs, after which rigid, affine and thin-plate spline models are used to estimate dense mappings throughout the image. Correspondences are derived from 3D features, distinctive generic image patterns that are automatically extracted from 3D ultrasound images and characterized in terms of their geometry (i.e., location, scale, and orientation) and a descriptor of local image appearance. Feature correspondences between ultrasound images are achieved based on a nearest-neighbor descriptor matching and probabilistic voting model similar to the Hough transform.

Results

Experiments demonstrate our method on intraoperative ultrasound images acquired before and after opening of the dura mater, during resection and after resection in nine clinical cases. A total of 1620 automatically extracted 3D feature correspondences were manually validated by eleven experts and used to guide the registration. Then, using manually labeled corresponding landmarks in the pre- and post-resection ultrasound images, we show that our feature-based registration reduces the mean target registration error from an initial value of 3.3 to 1.5 mm.

Conclusions

This result demonstrates that the 3D features promise to offer a robust and accurate solution for 3D ultrasound registration and to correct for brain shift in image-guided neurosurgery.

Migration and transformation of different phosphorus forms in rainfall runoff in bioretention system

Abstract

Artificial bioretention system consisting of Ophiopogon japonicus infiltration medium was used to simulate an infiltration experiment of rainfall runoff. Continuous extraction method was used to detect contents of inorganic phosphorus (P) under exchangeable state (Ex-P) and aluminium phosphate (Al–P) and iron phosphate (Fe–P) at different depths (0, 5, 15 and 35 cm) of soil infiltration medium in bioretention system. Effluent total P (TP) concentration of the system was also monitored. Results indicated that the adsorption of inorganic P, Al–P and Fe–P by soil infiltration medium was implemented layer by layer from top to bottom and gradually weakened. Moreover, Ex-P was gradually transformed into Al–P and Fe–P, whereas Al–P was gradually transformed into Fe–P; thus, Ex-P content reduced layer by layer, whereas Al–P and Fe–P gradually accumulated. The TP removal rate in runoff rainwater by the system was more than 90%, where the TP that was not used by plants was under dynamic equilibrium in water–soil–root system/biological system.

Evaluation of the influence of economic groups on the efficiency and quality of service of water companies: an empirical approach for Chile

Abstract

The privatization of water and sewerage services (WSS) has led to the foundation of water economic groups, which integrate several water companies and have gained notable importance at the global level. In the framework of benchmarking studies, there are no prior studies exploring the impact that economic groups have on the efficiency and quality of service provided by water companies. This study investigates, for the first time, whether the membership of water companies in an economic group influences their performance. Quantity- and quality-adjusted efficiency scores were computed using data envelopment analysis models. An empirical application was developed for the Chilean water industry since most of their water companies are private and belong to an economic group. The results show that independent water companies provide WSS with better quality than do water companies that belong to an economic group. From a statistical point of view, it was evident that membership in an economic group impacts both the quantity- and quality-adjusted efficiency scores of water companies. The results of this study illustrate that applying the model-firm regulation to the Chilean water industry has significant drawbacks that should be addressed by the water regulator to promote the long-term sustainability of the water industry.

Persulfate activation with rice husk-based magnetic biochar for degrading PAEs in marine sediments

Abstract

Phthalate esters (PAEs) can interfere with the endocrine systems of humans and wildlife. The main objective of this study was to evaluate the suitability of a composite for remediating marine sediments contaminated with PAEs. The composite was synthesized with magnetite nanoparticles (Fe₃O₄) and rice husk biochar (RHB) by using chemical co-precipitation. Fe₃O₄, RHB, and Fe₃O₄–RHB substantially activated sodium persulfate (Na₂S₂O₈, PS) oxidation to form SO₄^−• and thus degrade PAEs in marine sediments in a slurry system. The morphology and structural composition of the magnetic composites were examined using XRD, FTIR, environmental scanning electron microscopy–energy-dispersive X-ray spectrometry, and superconducting quantum interference device. The Fe₃O₄–RHB composites were confirmed to be prepared successfully. The influences of various parameters, including the PS concentration, composite loading, and initial pH, were investigated. The concentration of high-molecular-weight PAEs (HPAEs) in sediment was much higher than that of low-molecular-weight PAEs (LPAEs); di-(2-ethylhexyl) phthalate (DEHP) was an especially salient marker of PAE contamination in sediments. Furthermore, increasing the PS and Fe₃O₄–RHB doses accelerated PAE oxidation at pH 3.0; 83% degradation of PAEs was achieved when the PS and Fe₃O₄–RHB concentrations were increased to 2.3 × 10⁻² mM and 1.67 g/L, respectively. LPAEs such as dibutyl phthalate (DnBP) are easier to degrade than HPAEs such as DEHP, diisononyl phthalate (DINP), and diisodecyl phthalate (DIDP). In addition, possible activation mechanisms of the interactions between S₂O₈²⁻ and Fe²⁺/Fe³⁺ on the Fe₃O₄ surface, which involve an efficient electron transfer mediator of the RHB oxygen functional groups promoting the generation of SO₄^−• in the Fe₃O₄–RHB/PS system, were clarified. Thus, the Fe₃O₄–RHB/PS oxidation process is expected to be a viable method for remediating PAE-contaminated marine sediment.

Botulinum neurotoxin formulations: overcoming the confusion

Visual grading analysis of digital neonatal chest phantom X-ray images: Impact of detector type, dose and image processing on image quality

Abstract

Objectives

To evaluate the impact of digital detector, dose level and post-processing on neonatal chest phantom X-ray image quality (IQ).

Methods

A neonatal phantom was imaged using four different detectors: a CR powder phosphor (PIP), a CR needle phosphor (NIP) and two wireless CsI DR detectors (DXD and DRX). Five different dose levels were studied for each detector and two post-processing algorithms evaluated for each vendor. Three paediatric radiologists scored the images using European quality criteria plus additional questions on vascular lines, noise and disease simulation. Visual grading characteristics and ordinal regression statistics were used to evaluate the effect of detector type, post-processing and dose on VGA score (VGAS).

Results

No significant differences were found between the NIP, DXD and CRX detectors (p>0.05) whereas the PIP detector had significantly lower VGAS (p< 0.0001). Processing did not influence VGAS (p=0.819). Increasing dose resulted in significantly higher VGAS (p<0.0001). Visual grading analysis (VGA) identified a detector air kerma/image (DAK/image) of ~2.4 μGy as an ideal working point for NIP, DXD and DRX detectors.

Conclusions

VGAS tracked IQ differences between detectors and dose levels but not image post-processing changes. VGA showed a DAK/image value above which perceived IQ did not improve, potentially useful for commissioning.

Key points

• A VGA study detects IQ differences between detectors and dose levels.

• The NIP detector matched the VGAS of the CsI DR detectors.

• VGA data are useful in setting initial detector air kerma level.

• Differences in NNPS were consistent with changes in VGAS.

Glypican-1 circulating exosomes: a promising clue to individualize surveillance of pancreatic cysts?

Utility of MRI for cervical spine clearance in blunt trauma patients after a negative CT

Abstract

Purpose

To determine the utility of cervical spine MRI in blunt trauma evaluation for instability after a negative non-contrast cervical spine CT.

Methods

A review of medical records identified all adult patients with blunt trauma who underwent CT cervical spine followed by MRI within 48 h over a 33-month period. Utility of subsequent MRI was assessed in terms of findings and impact on outcome.

Results

A total of 1,271 patients with blunt cervical spine trauma underwent both cervical spine CT and MRI within 48 h; 1,080 patients were included in the study analysis. Sixty-six percent of patients with a CT cervical spine study had a negative study. Of these, the subsequent cervical spine MRI had positive findings in 20.9%; 92.6% had stable ligamentous or osseous injuries, 6.0% had unstable injuries and 1.3% had potentially unstable injuries. For unstable injury, the NPV for CT was 98.5%. In all 712 patients undergoing both CT and MRI, only 1.5% had unstable injuries, and only 0.42% had significant change in management.

Conclusions

MRI for blunt trauma evaluation remains not infrequent at our institution. MRI may have utility only in certain patients with persistent abnormal neurological examination.

Key Points

• MRI has limited utility after negative cervical CT in blunt trauma.

• MRI is frequently positive for non-specific soft-tissue injury.

• Unstable injury missed on CT is infrequent.

Could IVIM and ADC help in predicting the KRAS status in patients with rectal cancer?

Abstract

Purpose

To evaluate the diagnostic potential of DW-MRI relative parameters for differentiation of rectal cancers with different Kirsten rat sarcoma viral oncogene homologue (KRAS) mutation status.

Methods

Fifty-one patients with rectal cancer underwent diffusion-weighted MR imaging with eight b values. ADCs (including Max-ADC, Min-ADC and Mean-ADC) and IVIM parameters (D, pure diffusion; f, perfusion fraction; D*, pseudodiffusion coefficient) were respectively calculated by mono- and bi-exponential analysis. Patients were stratified into two groups: KRAS wild type and mutant. The DW-MRI-derived parameters between the KRAS wild-type group and KRAS mutant group were compared using the Mann-Whitney U test. Receiver-operating characteristic (ROC) analysis of discrimination between KRAS wild-type and KRAS mutant rectal cancer was performed for the DW-MRI-derived parameters.

Results

Max-ADC, Mean-ADC and D values were significantly lower in the KRAS mutant group than in the KRAS wild-type group, whereas a higher D* value was demonstrated in the KRAS mutant group. According to the ROC curve, Mean-ADC and D* values showed moderate diagnostic significance with the AUC values of 0.756 and 0.710, respectively. The cut-off values for Mean-ADC and D* were 1.43 × 10^-3mm²/s and 26.58 × 10^-3mm²/s, respectively.

Conclusion

Rectal cancers had distinctive diffusion/perfusion characteristics in different KRAS mutation statuses. The DW-MRI-derived parameters, specifically Mean-ADC and D*, show a moderate diagnostic significance for KRAS status.

Key Points

• Rectal cancers with different KRAS mutation statuses demonstrated distinctive diffusion/perfusion characteristics.

• Max-ADC, Mean-ADC and D values were lower in the KRAS mutant group.

• A higher D* value was demonstrated in the KRAS mutant group.

• IVIM-DW MRI may potentially help preoperative KRAS mutant status prediction.

Staging liver fibrosis with DWI: is there an added value for diffusion kurtosis imaging?

Abstract

Objectives

To assess liver fibrosis in patients with chronic liver disease using diffusion kurtosis imaging (DKI) in comparison with conventional diffusion-weighted imaging, with histology as reference standard.

Methods

This prospective study included 81 patients and DKI with b-values of 0, 200, 500, 1,000, 1,500, 2,000 s/mm² were performed. Mean diffusivity (MD), mean kurtosis (MK) and apparent diffusion coefficient (ADC) maps were calculated. The diagnostic efficacy of MD, MK and ADC for predicting stage 2 fibrosis or greater, and stage 3 fibrosis or greater were compared.

Results

The MD (rho=-0.491, p<0.001), MK (rho=0.537, p<0.001) and ADC (rho=-0.496, p<0.001) correlated significantly with fibrosis stages, and ADC exhibited a strong negative correlation with MK (rho=-0.968; p<0.001) and a moderate association with MD (rho=0.601, p<0.001). Areas under the curves (AUCs) for predicting stage 2 fibrosis or greater were not significantly different (p>0.05) between MK (0.809) and ADC (0.797) as well as between MD (0.715) and ADC. AUCs were also similar for MD (0.710), MK (0.768) and ADC (0.747) for predicting stage 3 fibrosis or greater.

Conclusion

Although DKI is feasible for predicting liver fibrosis in patients with chronic liver disease, MD and MK offer similar diagnostic performance to ADC values.

Key Points

• Diffusion kurtosis imaging is feasible for staging liver fibrosis.

• Diffusion kurtosis and monoexponential model are highly correlated.

• The kurtosis model offers no added value to the conventional, monoexponential model

Leveraging the coronary calcium scan beyond the coronary calcium score

Abstract

Non-contrast cardiac computed tomography in order to obtain the coronary artery calcium score has become an established diagnostic procedure in the clinical setting, and is commonly employed in clinical and population-based research. This state-of-the-art review paper highlights the potential gain in information that can be obtained from the non-contrast coronary calcium scans without any necessary modifications to the scan protocol. This includes markers of cardio-metabolic health, such as the amount of epicardial fat and liver fat, but also markers of general health including bone density and lung density. Finally, this paper addresses the importance of incidental findings and of radiation exposure accompanying imaging with non-contrast cardiac computed tomography. Despite the fact that coronary calcium scan protocols have been optimized for the visualization of coronary calcification in terms image quality and radiation exposure, it is important for radiologists, cardiologists and medical specialists in the field of preventive medicine to acknowledge that numerous additional markers of cardio-metabolic health and general health can be readily identified on a coronary calcium scan.

Key Points

• The coronary artery calcium score substantially increased the use of cardiac CT.

• Cardio-metabolic and general health markers may be derived without changes to the scan protocol.

• Those include epicardial fat, aortic valve calcifications, liver fat, bone density, and lung density.

• Clinicians must be aware of this potential additional yield from non-contrast cardiac CT.

Early percutaneous vertebroplasty helps motorsport professionals to resume competition soon after vertebral fracture

Accelerated real-time cardiac MRI using iterative sparse SENSE reconstruction: comparing performance in patients with sinus rhythm and atrial fibrillation

Abstract

Objectives

To compare accelerated real-time cardiac MRI (CMR) using sparse spatial and temporal undersampling and non-linear iterative SENSE reconstruction (RT IS SENSE) with real-time CMR (RT) and segmented CMR (SEG) in a cohort that included atrial fibrillation (AF) patients.

Methods

We evaluated 27 subjects, including 11 AF patients, by acquiring steady-state free precession cine images covering the left ventricle (LV) at 1.5 T with SEG (acceleration factor 2, TR 42 ms, 1.8 × 1.8 × 6 mm³), RT (acceleration factor 3, TR 62 ms, 3.0 × 3.0 × 7 mm³), and RT IS SENSE (acceleration factor 9.9-12, TR 42 ms, 2.0 × 2.0 × 7 mm³). We performed quantitative LV functional analysis in sinus rhythm (SR) patients and qualitatively scored image quality, noise and artefact using a 5-point Likert scale in the complete cohort and AF and SR subgroups.

Results

There was no difference between LV functional parameters between acquisitions in SR patients. RT IS SENSE short-axis image quality was superior to SEG (4.5 ± 0.6 vs. 3.9 ± 1.1, p = 0.007) and RT (3.8 ± 0.4, p = 0.003). There was reduced artefact in RT IS SENSE compared to SEG (4.4 ± 0.6 vs. 3.8 ± 1.2, p = 0.04), driven by arrhythmia performance. RT IS SENSE short-axis image quality was superior to SEG (4.6 ± 0.5 vs. 3.1 ± 1.0, p < 0.001) in the AF subgroup.

Conclusion

Accelerated real-time CMR with iterative sparse SENSE provides excellent clinical performance, especially in patients with AF.

Key Points

• Iterative sparse SENSE significantly accelerates real-time cardiovascular MRI acquisitions.

• It provides excellent qualitative and quantitative performance in sinus rhythm patients.

• It outperforms standard segmented acquisitions in patients with atrial fibrillation.

• It improves the trade-off between temporal and spatial resolution in real-time imaging.

Contrast-enhanced cadaver-specific computed tomography in gross anatomy teaching

Abstract

Objectives

To establish contrast-enhanced (CE) cadaver-specific post-mortem computed tomography (PMCT) in first-year gross anatomy teaching and quantitatively evaluate its learning benefit.

Methods

132 first-year medical students were included in this IRB-approved study and randomly assigned to an intervention group (n=59) provided with continuous access to CE and non-enhanced (NE) cadaver-specific PMCT-scans during the first-semester gross anatomy course, and a control group (n=73) that had only NE cadaver-specific PMCT data available. Four multiple-choice tests were carried out (15 questions each) subsequent to completion of the corresponding anatomy module: Head and neck anatomy, extremities, thorax, and abdomen. Median test results were compared in each module between the groups using the Wilcoxon rank-sum test. Additionally, participants of the intervention group answered a 15-item feedback-questionnaire.

Results

The intervention group achieved significantly higher test scores in head and neck anatomy (median=12.0, IQR=10.0–13.0) versus the control group (median=10.5, IQR=9.0–12.0) (p<0.01). There were no significant differences in the comparison of other modules. CEPMCT was highly appreciated by undergraduate medical students.

Conclusions

The incorporation of contrast-enhanced cadaver-specific PMCT-scans in gross anatomy teaching was proven to be feasible in the framework of the medical curriculum and significantly improved the students' learning performance in head and neck anatomy.

Key Points

• Cadaver-specific contrast-enhanced post-mortem CT (CEPMCT) is feasible in the medical curriculum.

• CEPMCT yields significantly improved learning performance in head and neck anatomy (p<0.01).

• CEPMCT is highly appreciated by medical students and used in tutor- or self-guided modes.

DNA double-strand breaks in blood lymphocytes induced by two-day 99m Tc-MIBI myocardial perfusion scintigraphy

Abstract

Objectives

To investigate DNA double-strand breaks (DSBs) in blood lymphocytes induced by two-day ^99mTc-MIBI myocardial perfusion scintigraphy (MPS) using y-H2AX immunofluorescence microscopy and to correlate the results with ^99mTc activity in blood samples.

Methods

Eleven patients who underwent two-day MPS were included. DSB blood sampling was performed before and 5min, 1h and 24h after the first and second radiotracer injections. ^99mTc activity was measured in each blood sample. For immunofluorescence microscopy, distinct foci representing DSBs were quantified in lymphocytes after staining for the phosphorylated histone variant y-H2AX.

Results

The ^99mTc-MIBI activity measured on days one and two was similar (254±25 and 258±27 MBq; p=0.594). Compared with baseline DSB foci (0.09±0.05/cell), a significant increase was found at 5min (0.19±0.04/cell) and 1h (0.18±0.04/cell) after the first injection and at 5min and 1h after the second injection (0.21±0.03 and 0.19±0.04/cell, respectively; p=0.003 for both). At 24h after the first and second injections, the number of DSB foci had returned to baseline (0.06±0.02 and 0.12±0.05/cell, respectively). ^99mTc activity levels in peripheral blood samples correlated well with DSB counts (r=0.451).

Conclusions

DSB counts reflect ^99mTc-MIBI activity after injection for two-day MPS, and might allow individual monitoring of biological effects of cardiac nuclear imaging.

Key Points

• Myocardial perfusion scintigraphy using ^99mTc induces time-dependent double-strand breaks (DSBs)

• γ-H2AX immunofluorescence microscopy shows DSB as an early response to radiotracer injection

• Activity measurements of ^99mTc correlate well with detected DSB

• DSB foci induced by ^99mTc return to baseline 24h after radiotracer injection

Radiomic signature as a diagnostic factor for histologic subtype classification of non-small cell lung cancer

Abstract

Objectives

To distinguish squamous cell carcinoma (SCC) from lung adenocarcinoma (ADC) based on a radiomic signature

Methods

This study involved 129 patients with non-small cell lung cancer (NSCLC) (81 in the training cohort and 48 in the independent validation cohort). Approximately 485 features were extracted from a manually outlined tumor region. The LASSO logistic regression model selected the key features of a radiomic signature. Receiver operating characteristic curve and area under the curve (AUC) were used to evaluate the performance of the radiomic signature in the training and validation cohorts.

Results

Five features were selected to construct the radiomic signature for histologic subtype classification. The performance of the radiomic signature to distinguish between lung ADC and SCC in both training and validation cohorts was good, with an AUC of 0.905 (95% confidence interval [CI]: 0.838 to 0.971), sensitivity of 0.830, and specificity of 0.929. In the validation cohort, the radiomic signature showed an AUC of 0.893 (95% CI: 0.789 to 0.996), sensitivity of 0.828, and specificity of 0.900.

Conclusions

A unique radiomic signature was constructed for use as a diagnostic factor for discriminating lung ADC from SCC. Patients with NSCLC will benefit from the proposed radiomic signature.

Key points

• Machine learning can be used for auxiliary distinguish in lung cancer.

• Radiomic signature can discriminate lung ADC from SCC.

• Radiomics can help to achieve precision medical treatment.

Editorial comment: the future of compositional MRI for cartilage

Abstract

This editorial comment refers to the article: "Detection of early cartilage damage: feasibility and potential of gagCEST imaging at 7T" by Brinkhof et al, Eur Radiol 2018.

The imaging of the dizzy patient: computed tomography versus magnetic resonance imaging

Analytical derivation of elasticity in breast phantoms for deformation tracking

Abstract

Purpose

Patient-specific biomedical modeling of the breast is of interest for medical applications such as image registration, image guided procedures and the alignment for biopsy or surgery purposes. The computation of elastic properties is essential to simulate deformations in a realistic way. This study presents an innovative analytical method to compute the elastic modulus and evaluate the elasticity of a breast using magnetic resonance (MRI) images of breast phantoms.

Methods

An analytical method for elasticity computation was developed and subsequently validated on a series of geometric shapes, and on four physical breast phantoms that are supported by a planar frame. This method can compute the elasticity of a shape directly from a set of MRI scans. For comparison, elasticity values were also computed numerically using two different simulation software packages.

Results

Application of the different methods on the geometric shapes shows that the analytically derived elongation differs from simulated elongation by less than 9% for cylindrical shapes, and up to 18% for other shapes that are also substantially vertically supported by a planar base. For the four physical breast phantoms, the analytically derived elasticity differs from numeric elasticity by 18% on average, which is in accordance with the difference in elongation estimation for the geometric shapes. The analytic method has shown to be multiple orders of magnitude faster than the numerical methods.

Conclusion

It can be concluded that the analytical elasticity computation method has good potential to supplement or replace numerical elasticity simulations in gravity-induced deformations, for shapes that are substantially supported by a planar base perpendicular to the gravitational field. The error is manageable, while the calculation procedure takes less than one second as opposed to multiple minutes with numerical methods. The results will be used in the MRI and Ultrasound Robotic Assisted Biopsy (MURAB) project.

Halotolerant plant-growth promoting rhizobacteria modulate gene expression and osmolyte production to improve salinity tolerance and growth in Capsicum annum L.

Abstract

Some rhizobacteria have demonstrated a noteworthy role in regulation of plant growth and biomass production under biotic and abiotic stresses. The present study was intended to explicate the ameliorative consequences of halotolerant plant growth-promoting rhizobacteria (HPGPR) on growth of capsicum plants subjected to salt stress. Salt stress was ascertained by supplementing 1 and 2 g NaCl kg⁻¹ soil. The HPGPR positively invigorated growth attributes, chlorophyll, protein contents, and water use efficiency (WUE) of supplemented capsicum plants under salinity stress conditions. Bacillus fortis strain SSB21 caused highest significant increase in shoot length, root length, and fresh and dry biomass production of capsicum plants grown under saline conditions. This multi-trait bacterium also increased biosynthesis of proline and up-regulated the expression profiles of stress related genes including CAPIP2, CaKR1, CaOSM1, and CAChi2. On the other hand, B. fortis strain SSB21 inoculated plants exhibited reduced level of ethylene, lipid peroxidation, and reactive oxygen species (ROS). All these together contribute to activate physiological and biochemical processes involved in the mitigation of the salinity induced stress in capsicum plants.

Twelve-Year Trajectories of Sitting Time are Associated With Frailty in Middle-Aged Women

Abstract

Prolonged sitting time is associated with several health outcomes; with limited evidence reporting associations with frailty. The aims of this study were to identify patterns of sitting time over 12 years in middle-aged women and examine associations of these patterns with frailty in older age. Our study examined 5,462 women born in 1946–1951 from the Australian Longitudinal Study on Women's Health who self-reported socio-demographic attributes, daily sitting time and frailty in 2001, and then every three years until 2013. Frailty was assessed using the FRAIL scale (score 0 = healthy; 1–2 = pre-frail; 3–5 = frail) and group-based trajectory analyses identified trajectories of sitting time. We identified five sitting time trajectories: low (27.5%); medium (41.5%; reference); increasing (8.2%); decreasing (18.0%); and high (4.9%). In adjusted models, the likelihoods (odds ratio: 95% confidence interval) of being frail were statistically higher for those in the increasing (1.29: 1.03, 1.61) and high (1.42: 1.10, 1.84) trajectories. In contrast, the low (0.86: 0.75, 0.98) trajectory group was less likely to be frail, with no difference in likelihood of frailty in the decreasing trajectory group. Our study suggests that patterns of sitting time over 12 years in middle-aged women predict frailty in older age.

Biomarker-Calibrated Total Sugars Intake and Risk of Type 2 Diabetes and Cardiovascular Disease in the Women's Health Initiative Observational Study

Abstract

The inconsistent findings from epidemiologic studies relating total sugars (TS) consumption to cardiovascular disease (CVD) or type 2 diabetes (T2D) risk may be partly due to measurement error (ME) in self-reported intake. Using regression calibration equations developed based on the predictive biomarker for TS and recovery biomarker for energy, we examined the association of TS with T2D and CVD risk, before and after dietary calibration, in 82,254 postmenopausal women of the Women's Health Initiative-Observational Study. After up to 16 years of follow-up (1993–2010), 6,621 T2D and 5,802 CVD incident cases were identified. The hazard ratio (HR) for T2D per 20% increase in calibrated TS was 0.94 (95% CI: 0.77, 1.15) in multivariable energy substitution (ES), and 1.00 (0.85, 1.18) in energy partition (EP) models. Multivariable HRs for total CVD were 0.97 (0.87, 1.09) from ES, and 0.91 (0.80, 1.04) from EP models. Uncalibrated TS generated a statistically significant inverse association with T2D and total CVD risk in both multivariable ES and EP models. The lack of conclusive findings from our calibrated analyses may be due to the low explanatory power of the calibration equations for TS, which could have led to incomplete deattenuation of the risk estimates.

Investigating the therapeutic potential of a probiotic in a clinical population with chronic hand dermatitis

Impact of tryptophan on the formation of TCNM in the process of UV/chlorine disinfection

Abstract

Low-pressure (LP) UV treatment after chlorine disinfection was associated with enhanced formation of trichloronitromethane (TCNM), a halonitromethane disinfection by-product (DBP), due to the chlorination of tryptophan. Evidence was found that the concentration of TCNM from tryptophan increased quickly to the maximum for the first instance. Moreover, the increase of TCNM under UV exceeded 10 times than under dark. Then, it was found to have an obvious decrease in the formation of TCNM, even finally hardly disappear. In order to elucidate reasons for this phenomenon, the effects of light intensity, initial tryptophan concentration, free chlorine concentration, pH, and tert-butanol (TBA) on the formation of TCNM were investigated under UV/chlorine treatment. Finally, the effects of tryptophan on the formation of TCNM and the direct photodegradation of TCNM under LP UV irradiation were studied for analyzing the possible pathways of TCNM formation from amino acid. Since amino acids are very common in water sources, further research into chemical oxidation of these species by LP UV and chlorine is recommended. It can help us to find the precursors of TCNM formation and reduce the risk of TCNM formation for drinking water and wastewater utilities.