Trends of absorption, scattering and total aerosol optical depths over India and surrounding oceanic regions from satellite observations: role of local production, transport and atmospheric dynamics

Abstract

The study examines trends of scattering, absorption and total aerosol optical depths (SAOD, AAOD and AOD) over India and surrounding oceanic regions and explores role of local production, long-range transport and atmospheric dynamics on observed trends. Long-term satellite observations are used to estimate trends and assess their statistical significance. Significant spatial and seasonal changes are observed in trends of SAOD, AAOD and AOD. AOD is observed to be increasing during post monsoon and winter over most of the land mass and surrounding oceanic regions, whereas decreasing trends over land and increasing trends over oceanic regions are observed in pre-monsoon and summer months. In general, SAOD and AAOD show similar trends (if there is any) as that of AOD over most of the regions in most of the months. Strongest positive trends over land regions are observed in November with trend of AOD greater than 0.01 year⁻¹, especially over Indo-Gangetic Plain (IGP). Increase of AOD over IGP in post monsoon is contributed significantly by absorbing aerosols with rate of increase ~ 0.005 AAOD year⁻¹. AAODs are observed to be increasing over Arabian Sea and Bay of Bengal (BoB) in December also, with rate ~ 0.003 AAOD year⁻¹. Strongest positive trends over Arabian Sea and BoB are observed in June with rate of increase greater than 0.02 AOD year⁻¹, whereas strong negative trends are observed over north-west India in the same period with rate of decrease greater than 0.02 AOD year⁻¹. Over IGP, AOD, AAOD and SAOD show contrasting trends in winter and summer seasons. AAOD exhibits strongest decreasing trend over IGP during April–June. Positive trends of AOD over Arabian Sea and BoB are favoured significantly by changes in circulation dynamics. Atmospheric convergence is observed to be strengthening over these regions in April and June, leading to more accumulation and hence positive trends of AOD. Aerosol transport over to the Arabian Sea is observed to be enhancing and contributing significantly to AOD increase over the Arabian Sea in pre-monsoon and summer months. Enhancement in aerosol transport over to the Arabian Sea is observed in pre-monsoon at higher altitudes above 3 km, whereas it is observed in summer at lower levels. However, decreasing trends of AOD over north-west India and IGP during pre-monsoon and summer are observed to be due to decrease in aerosol transport from the continental regions at the west.

The Editor's Choice

Editorial board

Long-term study of Cr, Ni, Zn, and P distribution in Typha domingensis growing in a constructed wetland

Abstract

The aim of this work was to study Cr, Ni, Zn, and P bioaccumulation in different compartments of Typha domingensis plants and sediment in a free-water surface constructed wetland for the treatment of a metallurgical effluent for 5 years. Removal efficiencies were satisfactory. To increase metal tolerance, its transport from belowground to aboveground tissues is reduced, being metal concentrations in the roots and rhizomes significantly higher than in the aerial and submerged parts of leaves. Regarding belowground tissues, metals were retained in the roots, while P was mainly accumulated in rhizomes. Bioaccumulation factors (BAFs) of Cr and Ni showed values near 1, and BAF of Zn and P were above 1 in several samplings, indicating bioaccumulation in the roots. Translocation factors (TFs) of Cr, Ni, and Zn were below 1, showing a scarce translocation from the roots to the aerial parts of the leaves, while the TF of P were above 1 in many samplings, indicating that this element is necessary for plant metabolism. The study of plant tissues where contaminants are accumulated allows gaining insight into the constructed wetland operation. The high translocation of P in T. domingensis makes this species suitable for its phytoextraction, while the low metal translocation makes T. domingensis suitable for phytostabilization.

Some aspects of the adsorption of glyphosate and its degradation products on montmorillonite

Abstract

The most worldwide used herbicide is glyphosate, phosphonomethylglycine (PMG). Consequently, a significant amount of PMG, its metabolites (sarcosine, SAR, and aminomethylphosphonic acid, AMPA) and the degradation product, methylphosphonic acid (MPA), reaches the soil, which acts as final sink. Because clays are one of the most reactive components of soils, expansive clays such as montmorillonite (Mt) are used to retain agriculture contaminants with some success. In this work, as a preliminary step for the evaluation of the risk that PMG, SAR, AMPA, and MPA occurrence could have on the environment, their adsorption on Mt surface was performed. The adsorption process was analyzed at constant adsorbate concentrations and two pH values to take into account the different protonation states of the amino group. DTA, XRD, zeta potential measurements, and XPS were used to identify the interactions or association mechanisms with the clay surface, the entry of adsorbates into the Mt interlayer, and electric charge changes on the Mt surface, and evaluate the acid-base surface complex constants, respectively. The interlayer thickness in acid media indicated that adsorbates are able to enter the interlayer in planar form. Besides, for the Mt-PMG sample, some PMG molecules could be also inserted as a bilayer or with a tilt angle of 52.4° in the interlayer. However, in alkaline media, the interlayer thickness indicated that the adsorbate arrangement differed from that of acidic media where PMG and MPA could have more than one orientation. The surface complex deprotonation constants were determined for the =NH⁺² ⇆ =NH+H⁺ process, being 3.0, 5.0, and 7.3 for PMG, AMPA, and SAR, respectively.

Relationships Among C-Reactive Protein, Alanine Aminotransferase, and Metabolic Syndrome in Apparently Healthy Chinese Subjects

Metabolic Syndrome and Related Disorders, Ahead of Print.

Gender Differences in the Effects of the Frequency of Physical Activity on the Incidence of Metabolic Syndrome: Results from a Middle-Aged Community Cohort in Taiwan

Metabolic Syndrome and Related Disorders, Ahead of Print.

Bringing big data from social media reviews to quality improvement

Determination of size-segregated elements in diesel-biodiesel blend exhaust emissions

Abstract

This study was based on the determination of metals in particulate matter emitted by a typical diesel engine used by busses and trucks in Brazil. Emissions were sampled using a cascade impactor, and the engine was operated using diesel with 5% (B5), 10% (B10), 15% (B15), and 20% (B20) of biodiesel. The particulate matter was stratified in different sizes, i.e., 18, 5.6, 3.2, 1.8, 1.0, 0.560, 0.320, 0.180, 0.100, and 0.056 μm. Cd, Co, Cr, Cu, Mn, Mo, Ni, Pb, V, and Zn with concentrations within 10 to 1000 ng m⁻³ were determined. The results indicate a trend in the prevalence of lead, nickel, and chromium in coarse particles and nanoparticles in all blends of fuels. By comparing the results of B5, B10, B15, and B20 fuels, we can confirm that the addition of biodiesel to diesel promotes a reduction of emissions, and by comparing the behavior of the concentration of all elements analyzed, emissions by B10 and B15 fuels are similar, while B5 and B20 suffer significant changes during the process of combustion. Multivariate statistical analysis was used, and it indicates possible sources in three clusters, one for Ni, other for Cr-Mn, and the last one for other metals.

Histopathological patterns in dermatitis artefacta

JDDG: Journal der Deutschen Dermatologischen Gesellschaft, EarlyView.

Psoriasis vulgaris in a patient with pemphigus vulgaris on corticosteroid therapy

JDDG: Journal der Deutschen Dermatologischen Gesellschaft, EarlyView.

Moderators of angiogenesis in muscle flaps: a non-randomised animal study

Publication date: Available online 23 April 2018
Source:Journal of Plastic, Reconstructive & Aesthetic Surgery
Author(s): K. Bradshaw, M. Wagels
IntroductionA muscle flap can survive a pedicle injury under favourable conditions. In the reconstruction of compound limb injuries, the wound milieu is variable and may affect the rate and manner of neovascularisation. Our aim is to determine the effect of some key clinical variables on neovascularisation in muscle flaps in an animal model.MethodologyPectoralis profundus was raised in 60 rats and covered with skin graft. Fifteen cases were allocated to groups: separation of the flap from the skin inset (S), inflammation by inoculation with Staphylococcus aureus (I), flap elevation with Harmonic Scalpel (H), preservation of the motor nerve (N) and compared to controls (C). Graft-take and wound complications were assessed five days later, as well as perfusion before and after pedicle ligation, using Laser Doppler Flowmetry and neovascularisation using barium angiography.ResultsFlaps with an intact motor nerve had significantly higher graft take than controls (59% vs 29%). Perfusion changed less than controls in all study groups, though the extent of flap necrosis was not significantly different. Only flaps raised with the harmonic scalpel generated more new vessels than controls at the inset (9.6 vs 3.2), particularly at the origin of the muscle (1.10 vs 0.19).ConclusionsAll study groups were less dependant on their pedicle for perfusion than controls. The use of the harmonic scalpel and increased inflammation seem pro-angiogenic, though they do not reduce flap necrosis after simulated pedicle injury. Neovascularisation will preferentially bridge to skin at the inset rather than tissues in the base of the wound. It is likely that flap necrosis is the result of a combination of unfavourable variables rather than one in isolation.

Deciding Staged Battles of the Past: On the Rhetorics of Olaf Müller’s Historical Philosophy of Science

Abstract

Since Plato's massive critique of the Sophists rhetoric's ill repute runs through the history of western philosophy denunciating methods of rhetoric as in large part dishonest persuasion strategies which are at most marginally interested in dealing with truths. This judgement falls way too short insofar as it distorts the historically grown stock labeled "rhetoric" not only in the Aristotelian work. With reference to Olaf Müller's philosophical book (Mehr Licht: Goethe mit Newton im Streit um die Farben, S. Fischer, Frankfurt am Main, 2015) addressing the "controversy" between Goethe and Newton about the nature of light, I will study the different rhetorical models and methods used by Newton and Goethe and also Müller himself. It becomes apparent that even works attempting to decide who was right in the long run do far more than trying to evoke true "representations" of facts or truths in the reader. The specific use of language patterns provides deeper insight into an author's mindset towards the subject area discussed in his work and generally speaking the investigation of the rhetoric of science and philosophy leads to a better understanding of different epistemic cultures both in philosophy and science.

Intestinal microbiome of broiler chickens after use of nanoparticles and metal salts

Abstract

The research included the study of influence of ultrafine particle preparations (nanoparticles of copper, zinc, iron, CuZn alloy) and metal salts (iron pyrophosphate, copper asparginate, zinc asparginate) on the composition of cecal microbiota of broiler chickens. Before adding the studied nanoparticles and metal salts to the diet, cecal microbiota of broiler chickens was represented by 76% Firmicutes taxon and 16% Bacteroidetes. Numerous among them were the bacteria of the taxa Anaerotruncus spp., Lactobacillus spp., Blautia spp., Alistipes spp., and Bacteroides spp.; they constituted 18, 17, 11, and 6%, respectively. A peculiarity of action of the most analyzed metals in nanoform and in the form of salts was a decrease in the number of phylum Firmicutes bacteria and an increase in the number of microorganisms of the phylum Bacteroidetes. The number of bacteria belonging to the families Ruminococcaceae (III, IV, V, VII, and VIII groups), Bacteroidaceae (in all experimental groups), and Lachnospiraceae (I, IV, V, and VII groups) was registered within the taxa of Firmicutes and Bacteroidetes. At the same time, in some experimental groups, the number of bacteria of the family Lachnospiraceae (II, III, and VIII) decreased in the intestine. The data obtained can be used to assess the possibility of using metal nanoparticles in the poultry diet, as a micronutrient preparation, to correct dysbiosis and to improve the utilization of fodder energy.

The dispositional architecture of epistemic reasons

Abstract

Epistemic reasons are meant to provide justification for beliefs. In this paper, I will be concerned with the requirements that have to be met if reasons are to discharge this function. It is widely recognized, however, that only possessed reasons can justify beliefs and actions. But what are the conditions that have to be satisfied in order for one to possess reasons? I shall begin by motivating a particular condition, namely, the 'treating' requirement that has been deemed to be necessary for possessing reasons. In Sect. 1, I explain and criticize some of the existing accounts of the treating requirement for reason-possession. In Sect. 2, I will suggest a dispositional account of reason-possession in which the treating condition features prominently. Section 3 will deal with the some of the consequences of this account for such issues as the structure of epistemic defeat, the immediacy of perceptual justification and logical knowledge.

Occurrence of polybrominated diphenyl ethers in floor and elevated surface house dust from Shanghai, China

Abstract

House dust is the main source of human exposure to flame retardants by ingestion. This study investigated the occurrence of polybrominated diphenyl ethers (PBDEs) in indoor dust from 22 houses in Shanghai, China. House dust was separately collected from the floor and elevated furnishings surface (mostly between 0.5 and 2 m height) for comparison. The concentrations of ∑₂₂ PBDEs ranged from 19.4 to 3280 ng/g (with a geometric mean of 203 ng/g) and from 55.1 to 792 ng/g (with a geometric mean of 166 ng/g) in floor dust (FD) and elevated surface dust (ESD), respectively. BDE-209 was the predominant congener, accounting for about 73.1% of total PBDE burdens. In terms of congener profiles, the comparison of FD and ESD revealed no significant differences except for the ratio of BDE-47/BDE-99. ESD samples displayed a ratio of BDE-47/BDE-99 very similar to commercial penta-BDE products DE-71 while the ratio in FD was exceptionally higher. Significant correlation was found between concentrations of commercial penta-BDE compositions in FD and ESD (p < 0.05). Except for some occasional values, PBDE levels in house dust exhibited temporal stability. Human exposure to PBDEs via dust ingestion was estimated. The highest daily intake of PBDEs was for toddlers by using 95th percentile concentrations of PBDEs via high dust ingestion in FD (23.07 ng/kg bw/day). About 20-fold difference in exposure estimates between toddlers and adults supports that toddlers are facing greater risk from indoor floor dust. Expectedly, this study highlighted the point that residents in Shanghai were exposed to low doses of PBDEs in house dust.

Transformations of 2-line ferrihydrite and its effect on cadmium adsorption

Abstract

In this study, 2LFh was synthesized, and the effects of 2LFh synthesis in the laboratory as well as its synthetic products' mineral crystal phase changes during high temperature aging process caused by Ca²⁺, Mg²⁺, and Cl⁻ were also studied. In addition, the Cd²⁺ adsorption effects of the products above with different pH values and different Cd²⁺ concentrations were studied in this experiment. The results showed that the existence of Ca²⁺ had no significant effect on the synthesis and aging of 2LFh. However, in the presence of Mg²⁺ and Cl⁻, the akaganeite could be found in the synthetic material, and with the increase of the ion concentration, the crystallinity of the formed akaganeite was higher. And akaganeite had a significant inhibitory effect on the aging of 2LFh, causing the Cd²⁺adsorption effect of 2LFh after aging was better than that of pure 2LFh. The adsorption and removal rates of Cd²⁺ in Fh2 series and Fh2-200 series were increased with the increase of initial concentration. With the increase of pH, the adsorption capacity and removal rate were increased, and the removal rate reached nearly 100% when pH value is ranging from 10 to 11. The isothermal adsorption experiment showed that the isothermal adsorption process of Cd²⁺ in Fh2 series and Fh2-200 series was in accordance with the Freundlich model. The affinity coefficient (Kf) of the Freundlich model of Fh2-200 series arranged in descending order is Fh2-200-Mgs> Fh2-200-Cas> Fh2-200s, showing that the Cd²⁺ adsorption capacity of Fh2-200 was relatively weak, while that of Fh2-200-Ca series and Fh2-200-Mg series was relatively strong, which was confirmed by the experimental results.

Fixed-bed operation for manganese removal from water using chitosan/bentonite/MnO composite beads

Abstract

In the present study, a new composite adsorbent, chitosan/bentonite/manganese oxide (CBMnO) beads, cross-linked with tetraethyl-ortho-silicate (TEOS) was applied in a fixed-bed column for the removal of Mn (II) from water. The adsorbent was characterised by scanning electron microscopy (SEM), Fourier transform infra-red (FT-IR), N₂ adsorption-desorption and X-ray photoelectron spectroscopy (XPS) techniques, and moreover the point of zero charge (pH_pzc) was determined. The extend of Mn (II) breakthrough behaviour was investigated by varying bed mass, flow rate and influent concentration, and by using real environmental water samples. The dynamics of the column showed great dependency of breakthrough curves on the process conditions. The breakthrough time (t_b ), bed exhaustion time (t_s ), bed capacity (q_e ) and the overall bed efficiency (R%) increased with an increase in bed mass, but decreased with the increase in both influent flow rate and concentration. Non-linear regression suggested that the Thomas model effectively described the breakthrough curves while large-scale column performance could be estimated by the bed depth service time (BDST) model. Experiments with environmental water revealed that coexisting ions had little impact on Mn (II) removal, and it was possible to achieve 6.0 mg/g breakthrough capacity (q_b ), 4.0 L total treated water and 651 bed volumes processed with an initial concentration of 38.5 mg/L and 5.0 g bed mass. The exhausted bed could be regenerated with 0.001 M nitric acid solution within 1 h, and the sorbent could be reused twice without any significant loss of capacity. The findings advocate that CBMnO composite beads can provide an efficient scavenging pathway for Mn (II) in polluted water.

Enhanced adsorption of uranium by modified red muds: adsorption behavior study

Abstract

Uranium is a hazardous and radioactive element. Effective removal of uranium from wastewater stream requires advanced functional materials and reliable technologies. Red mud is a type of low-cost adsorbent which is widely used in the adsorption process. In the present work, we successfully modified the raw red mud to gain a series of highly efficient sorbents for uranium removal. They are nitric acid dealkalized red mud (DRM), aluminum nitrate modified red mud (ARM), and ferric nitrate modified red mud (FRM). The adsorption efficiencies of uranium(VI) by DRM, ARM, and FRM were 74.50, 95.56, and 98.75% in their optimal immobilization regions, respectively. The chemisorption of uranium dominates the adsorption process of FRM, while as to physical adsorption dominates the adsorption process of ARM and DRM. Both DRM and ARM reached their maximum adsorption capacities at 10 min while that for FRM occurred at 30 min. FRM performed much stronger anti-interference ability to the influence of carbonate and calcium. The outstanding adsorption ability of these modified red muds is mainly due to the enhancement of ion exchange, co-precipitation, and electrostatic attraction by red mud's active components and functional groups.

Identification of phytotoxins in different plant parts of Brassica napus and their influence on mung bean

Abstract

Plants in Brassica genus have been found to possess strong allelopathic potential. They may inhibit seed germination and emergence of subsequent crops following them in a rotation system. Series of laboratory and greenhouse experiments were conducted to determine the allelopathic impacts of Brassica napus L. against mung bean. We studied (1) the effects of aqueous extract (5%) of different plant parts (root, stem, leaf, flower, and whole plant) of B. napus, (2) the effects of leaf and flower extracts of B. napus at 0, 1, 2, 3, and 4% concentrations, and (3) the effect of residues of different B. napus plant parts and decomposition periods (0, 7, 14, and 21 days) on germination and seedling growth of mung bean. Various types of phenolics including quercitin, chlorogenic acid, p-coumeric acid, m-coumaric acid, benzoic acid, caffeic acid, syringic acid, vanillic acid, ferulic acid, cinamic acid, and gallic acid were identified in plant parts of B. napus. Among aqueous extracts of various plant parts, leaf and flower were found to have stronger inhibitory effects on germination and seedling growth traits of mung bean, higher concentrations were more toxic. The decomposition period changed the phtotoxic effect of residues, more inhibitory effect was shown at 14 days decomposition while decomposition for 21 days reduced inhibitory effect. The more total water-soluble phenolic was found in 5% (w/v) aqueous extract and 5% (w/w) residues of B. napus flowers at 14 days of decomposition (89.80 and 10.47 mg L⁻¹), respectively. The strong inhibitory effects of B. napus should be managed when followed in rotation.

Effects of mining activities on evolution of water chemistry in coal-bearing aquifers in karst region of Midwestern Guizhou, China: evidences from δ 13 C of dissolved inorganic carbon and δ 34 S of sulfate

Abstract

The generation of acid mine drainage (AMD) may accelerate watershed erosion and promote the migration of heavy metals, then threaten local ecosystems such as aquatic life and even human health. Previous studies have focused primarily on influence of AMD in surface environment. In order to reveal the acidizing processes in karst high-sulfur coalfield in Southwest China, this study, by contrast, focused on the hydrogeochemical evolution process and acidification mechanism of mine water in Zhijin coalfield, western Guizhou Province. The oxidation of pyrite and other sulfides induced strong acidification of mine water according to the water chemical analysis. As a result, a series of geochemical processes such as dissolution of carbonates and silicates, hydrolysis of metal ions, and degassing of CO₂ complicated water chemical evolution. The dissolution of silicates controlled the chemical composition of mine water, but more carbonates might be dissolved during the acidification of mine water. The sources of sulfate are quite different in water samples collected from the two selected mine. According to sulfur isotope analysis, the dissolution of gypsum is the primary source of sulfate in samples from Hongfa mine, whereas sulfide oxidation contributed a large amount of sulfate to the mine water in Fenghuangshan mine. The dissolution of carbonates should be an important source of DIC in mine water and CO₂ originating from organic mineralization might also have a certain contribution. This study elucidated the groundwater chemical evolution processes in high-sulfur coal-bearing strata and provided a foundation for further study of carbonates erosion and carbon emission during acidification of mine water.

T cells isolated from patients with checkpoint inhibitor resistant-melanoma are functional and can mediate tumor regression

Abstract

Background

The majority of patients with metastatic melanoma obtain only short-term or no benefit at all from checkpoint inhibitor (CPI) immunotherapy. In this study, we investigated whether the immune system of patients progressing following CPI treatment was able to generate functional tumor-specific immune responses.

Materials and methods

Tumor-infiltrating lymphocytes (TILs) were isolated and expanded from metastatic melanoma lesions which progressed during or after anti-PD-1 and anti-CTLA-4 treatment. Tumor-specific immune responses were assessed with co-culture assays of TILs and autologous tumor cells.

Results

TILs from 23 metastases of individual patients could be assessed for T cell recognition of autologous tumor cells. All metastases were progressive on or following anti-PD-1 (23/23, 100%), and the majority also after anti-CTLA-4 (17/23, 74%). Functional anti-tumor immune responses were detected in 19/23 patients (83%). Both CD8⁺ (in 18/23 patients, 78%) and CD4⁺ (in 16/23 patients, 70%) TILs were able to recognize autologous tumors. A large fraction of CD8⁺ TILs (median 23%, range 1.0-84%) recognized tumor cells. This is similar to the cohorts of unselected patient populations with metastatic melanoma presented in previous studies. The localization of intratumoral immune infiltrates was heterogeneous among samples. In a phase I/II clinical trial, TILs were administered with lymphodepleting chemotherapy, pegIFNα2b and IL-2 to 12 patients with CPI-resistant melanoma. Out of 12 patients who previously failed CPI therapy, treatment with TILs resulted in two partial responses, of which one is ongoing.

Conclusions

Tumor-reactive T cells appear to heavily infiltrate the tumor microenvironment of patients who failed previous CPI treatment. These patients can still respond to an infusion of unselected autologous TILs. Our results warrant further testing of novel immune re-activation strategies in melanoma patients who failed multiple CPI therapy.

The allure of “ALUR”

Further evidence to support judicious use of antibiotics in patients with cancer

Anti-infective Vaccination Strategies in Patients with Hematologic Malignancies or Solid Tumors – Guideline of the Infectious Diseases Working Party (AGIHO) of the German Society for Hematology and Medical Oncology (DGHO)

Abstract

Infectious complications are a significant cause of morbidity and mortality in patients with malignancies specifically when receiving anticancer treatments. Prevention of infection through vaccines is an important aspect of clinical care of cancer patients. Immunocompromising effects of the underlying disease as well as of antineoplastic therapies need to be considered when devising vaccination strategies. This guideline provides clinical recommendations on vaccine use in cancer patients including autologous stem cell transplant recipients, while allogeneic stem cell transplantation is subject of a separate guideline. The document was prepared by the Infectious Diseases Working Party (AGIHO) of the German Society for Hematology and Medical Oncology (DGHO) by reviewing currently available data and applying evidence-based medicine criteria.

The case for ‘successfully’ treating hormone naïve metastatic prostate cancer

Editorial Board

Publication date: March 2018
Source:Annales de Dermatologie et de Vénéréologie, Volume 145, Supplement 3

Éditorial

Publication date: March 2018
Source:Annales de Dermatologie et de Vénéréologie, Volume 145, Supplement 3
Author(s): B. Cribier

High waterborne Mg does not attenuate the toxic effects of Fe, Mn, and Ba on Na + regulation of Amazonian armored catfish tamoatá ( Hoplosternum litoralle )

Abstract

Formation water (FoW) is a by-product from oil and gas production and usually has high concentrations of soluble salts and metals. Calcium (Ca) and magnesium (Mg) have been shown to reduce the toxicity of metals to aquatic animals, and previous study showed that high waterborne Ca exerts mild effect against disturbances on Na⁺ regulation in Amazonian armored catfish tamoatá (Hoplosternum littorale) acutely exposed to high Fe, Mn, and Ba levels. Here, we hypothesized that high Mg levels might also reduce the toxic effects of these metals on Na⁺ regulation of tamoatá. The exposure to 5% FoW promoted an increase in Na⁺ uptake and a rapid accumulation of Na⁺ in all tissues analyzed (kidney<plasma<gills<carcass<liver), besides increasing the branchial activity of both NKA and v-type H⁺-ATPase in fish. High waterborne Mg lowered Na⁺ efflux rates and markedly inhibited Na⁺ uptake, and also reduced both NKA activity and newly Na⁺ accumulation in gills of fish. High Fe levels increased Na⁺ net losses and inhibited Na⁺ uptake in tamoatá. The diffusive Na⁺ losses and the newly accumulated Na⁺ in gills were reduced in fish exposed to high Mn and Ba. High waterborne Ba also inhibited NKA in gills, while both high Mn and Ba inhibited v-type H⁺-ATPase in kidney of tamoatá. High Mg did not lessen the toxic effect of Fe on Na⁺ net fluxes, and reduced even more Na⁺ uptake and the newly Na⁺ accumulation in gills and plasma, and did not prevent the inhibition of both NKA and v-type H⁺-ATPases in kidney. Furthermore, Mg did not attenuate the effect of Mn on inhibition Na⁺ uptake, keeping the activity of v-type H⁺-ATPase in kidney significantly lowered. High Mg levels mildly attenuated the effects of Ba in Na⁺ balance by increasing the new accumulation of Na⁺ in liver, and restore the activity of both NKA and v-type H⁺-ATPase in gills of tamoatá. Overall, high waterborne Mg does not have a strong contribution to, or have only minor effects, in protecting tamoatá against disruptions in Na⁺ regulation mediated by high Fe, Mn, and Ba levels.

Monitoring substrate enables real-time regulation of a protein localization pathway

Abstract

Protein localization machinery supports cell survival and physiology, suggesting the potential importance of its expression regulation. Here, we summarize a remarkable scheme of regulation, which allows real-time feedback regulation of the machinery expression. A class of regulatory nascent polypeptides, called monitoring substrates, undergoes force-sensitive translation arrest. The resulting ribosome stalling on the mRNA then affects mRNA folding to expose the ribosome-binding site of the downstream target gene and up-regulate its translation. The target gene encodes a component of the localization machinery, whose physical action against the monitoring substrate leads to arrest cancellation. Thus, this scheme of feedback loop allows the cell to adjust the amount of the machinery to correlate inversely with the effectiveness of the process at a given moment. The system appears to have emerged late in evolution, in which a narrow range of organisms selected a distinct monitoring substrate-machinery combination. Currently, regulatory systems of SecM-SecA, VemP-SecDF2, and MifM-YidC2 are known to occur in different bacterial species.

Identification of a unique transcriptional architecture for the sigS operon in Staphylococcus aureus.

Abstract

Staphylococcus aureus possess three alternative σ factors, including a lone extracytoplasmic function σ factor, σ^S. Our group previously identified and characterized this element, mapping three sigS promoters, demonstrating its inducibility during stress and virulence inducing conditions, and demonstrating a role for this factor in disease causation. In the present study, we identify a fourth promoter of the sigS operon, termed P4, located in a unique position internal to the sigS coding region. Transcriptional profiling revealed that expression from P4 is dominant to the three upstream promoters, particularly upon exposure to chemical stressors that elicit DNA damage and disrupt cell wall stability; each of which have previously been shown to stimulate sigS expression. Importantly, expression of this fourth promoter, followed by at least one or more of the upstream promoters, is induced during growth in serum and upon phagocytosis by RAW 264.7 murine macrophage-like cells. Finally, we demonstrate that an upstream gene, SACOL1829, bears a large 3' UTR that spans the sigS-SACOL1828 coding region, and may serve to compete with the P4 transcript to inhibit σ^S production. Collectively, these findings reveal a unique operon architecture for the sigS locus that indicates the potential for novel regulatory mechanisms governing its expression.

Bacteria on display- can we, and should we? Artistically exploring the ethics of public engagement with science in Microbiology

Abstract

The field of microbiology presents unique opportunities, and accompanying challenges, for artistic collaborations. On one hand, artistic works enable exploration of the aesthetics and of issues in biomedical science and new technologies, and draw in new, non-scientific audiences. On the other hand, creating art with microbes requires rigorous consideration of health and safety.Artists working in this field, known as Bio Art, tend to want to push the boundaries of what is possible or 'known', and work with new biomedical tools as they become available. However, when an artist's proposed work is raising novel questions where the risks are not fully understood, who should decide if the benefits outweigh the consequences?The reflections of an art-collaborating scientist are related. Also considered is how close working relationships between disciplines can enable new ethical frameworks which consider these decisions, respecting artists' endeavours as a beneficial form of research in its own right, and even learning from the rich perspectives of artists to broaden reflections on the practice of science.

Angio-3, a 10-residue peptide derived from human plasminogen kringle 3, suppresses tumor growth in mice via impeding both angiogenesis and vascular permeability

Abstract

Anti-angiogenesis therapy is an established therapeutic strategy for cancer. The endogenous angiogenic inhibitor angiostatin contains the first 3–4 kringle domains of plasminogen and inhibits both angiogenesis and vascular permeability. We present here a 10-residue peptide, Angio-3, derived from plasminogen kringle 3, which retains the functions of angiostatin in inhibiting both angiogenesis and vascular permeability. NMR studies indicate that Angio-3 holds a solution structure similar to the corresponding region of kringle 3. Mechanistically, Angio-3 inhibited both VEGF- and bFGF-induced angiogenesis by inhibiting EC proliferation and migration while inducing apoptosis. Inhibition of VEGF-induced vascular permeability results from its ability to impede VEGF-induced dissociation of adherens junction and tight junction proteins as well as the formation of actin stress fibers. When administered intravenously, Angio-3 inhibited subcutaneous breast cancer and melanoma growth by suppressing both tumor angiogenesis and intra-tumor vascular permeability. Hence, Angio-3 is a novel dual inhibitor of angiogenesis and vascular permeability. It is valuable as a lead peptide that can be further developed as therapeutics for diseases involving excessive angiogenesis and/or vascular permeability.

Integration of a photocatalytic multi-tube reactor for indoor air purification in HVAC systems: a feasibility study

Abstract

This work is focused on an in-depth experimental characterization of multi-tube reactors for indoor air purification integrated in ventilation systems. Glass tubes were selected as an excellent photocatalyst substrate to meet the challenging requirements of the operating conditions in a ventilation system in which high flow rates are typical. Glass tubes show a low-pressure drop which reduces the energy demand of the ventilator, and additionally, they provide a large exposed surface area to allow interaction between indoor air contaminants and the photocatalyst. Furthermore, the performance of a range of P25-loaded sol-gel coatings was investigated, based on their adhesion properties and photocatalytic activities. Moreover, the UV light transmission and photocatalytic reactor performance under various operating conditions were studied. These results provide vital insights for the further development and scaling up of multi-tube reactors in ventilation systems which can provide a better comfort, improved air quality in indoor environments, and reduced human exposure to harmful pollutants.