Increasing the Accuracy of Optic Nerve Measurement Using 3D Volumetry [LETTERS]

REPLY: [LETTERS]

Association of Quantified Location-Specific Blood Volumes with Delayed Cerebral Ischemia after Aneurysmal Subarachnoid Hemorrhage [ADULT BRAIN]

BACKGROUND AND PURPOSE:

Delayed cerebral ischemia is a severe complication of aneurysmal SAH and is associated with a high case morbidity and fatality. The total blood volume and the presence of intraventricular blood on CT after aneurysmal SAH are associated with delayed cerebral ischemia. Whether quantified location-specific (cisternal, intraventricular, parenchymal, and subdural) blood volumes are associated with delayed cerebral ischemia has been infrequently researched. This study aimed to associate quantified location-specific blood volumes with delayed cerebral ischemia.

MATERIALS AND METHODS:

Clinical and radiologic data were collected retrospectively from consecutive patients with aneurysmal SAH with available CT scans within 24 hours after ictus admitted to 2 academic centers between January 2009 and December 2011. Total blood volume was quantified using an automatic hemorrhage-segmentation algorithm. Segmented blood was manually classified as cisternal, intraventricular, intraparenchymal, or subdural. Adjusted ORs with 95% confidence intervals for delayed cerebral ischemia per milliliter of location-specific blood were calculated using multivariable logistic regression analysis.

RESULTS:

We included 282 patients. Per milliliter increase in blood volume, the adjusted OR for delayed cerebral ischemia was 1.02 (95% CI, 1.01–1.04) for cisternal, 1.02 (95% CI, 1.00–1.04) for intraventricular, 0.99 (95% CI, 0.97–1.02) for intraparenchymal, and 0.96 (95% CI, 0.86–1.07) for subdural blood.

CONCLUSIONS:

Our findings suggest that in patients with aneurysmal subarachnoid hemorrhage, the cisternal blood volume has a stronger relation with delayed cerebral ischemia than the blood volumes at other locations in the brain.

Management of Small Unruptured Intracranial Aneurysms: A Survey of Neuroradiologists [INTERVENTIONAL]

BACKGROUND AND PURPOSE:

The long-term history and management of unruptured intracranial aneurysms is not well understood. Our aim was to determine current practice patterns in the management of unruptured intracranial aneurysms, especially regarding imaging surveillance for conservatively managed aneurysms of this type.

MATERIALS AND METHODS:

An on-line survey was designed to examine physician practice and preference regarding the management of small unruptured intracranial aneurysms (≤7 mm in diameter). The survey was circulated to members of the American Society of Neuroradiology. Participation was voluntary, and all responses were anonymous.

RESULTS:

A total of 227 individual survey responses were obtained and included in the analysis with 54.6% (124/227) from diagnostic neuroradiologists (practicing >50% neuroradiology) and one-third (29%) from neurointerventional radiologists. One hundred seventy-three of 227 responded that routine, periodic imaging surveillance would be appropriate for conservatively managed unruptured intracranial aneurysms, and 84% of respondents recommended surveillance frequency of at least once a year. Fifty-nine percent favored indefinite, life-long follow-up for small unruptured intracranial aneurysms, and a similar number of respondents favored noncontrast MR angiography for aneurysm follow-up. Significant heterogeneity was found in size measurements used to assess aneurysms and criteria used to define growth on surveillance imaging.

CONCLUSIONS:

The natural history of intracranial aneurysms is not well-understood. A large proportion of incidentally detected, unruptured aneurysms are small (<7 mm). The survey results show significant heterogeneity in practice even among neuroradiologists and underlies the need to standardize imaging practice. Further studies are needed to assess the optimal frequency and duration of surveillance imaging for unruptured intracranial aneurysms. The criteria used to measure aneurysms and define growth on imaging also need to be standardized.

Surpass Streamline Flow-Diverter Embolization Device for Treatment of Iatrogenic and Traumatic Internal Carotid Artery Injuries [INTERVENTIONAL]

SUMMARY:

Iatrogenic and traumatic cerebral internal carotid artery injuries are uncommon but potentially lethal complications. Direct surgical repair of ICA injuries may be difficult in an acute setting. However, endovascular treatment with a flow-diverter embolization device is a feasible alternative technique that we experienced. In this clinical report, we describe demographic data, radiographic images, lesion characteristics, endovascular procedure notes, postprocedural hospital course, and follow-up digital subtraction angiography of 5 patients. At least 6-month follow-up was available in all patients without occurrence of rebleeding and other complications.

Under Pressure: Comparison of Aspiration Techniques for Endovascular Mechanical Thrombectomy [INTERVENTIONAL]

BACKGROUND AND PURPOSE:

Blood flow should be interrupted during mechanical thrombectomy to prevent embolization of clot fragments. The purpose of our study was to provide a handy overview of the most common aspiration devices and to quantify their flow characteristics.

MATERIALS AND METHODS:

We assessed volumetric flow rates generated by a 60-mL VacLok vacuum pressure syringe, a Pump MAX aspiration pump, and a Dominant Flex suction pump connected to the following: 1) an 8F long sheath, 2) an 8F balloon-guide catheter, 3) an ACE 64 distal aspiration catheter, and 4) an AXS Catalyst 6 Distal Access Catheter. We used a water/glycerol solution, which was kept at a constant temperature of 20°C (viscosity, 3.7 mPa · s).

RESULTS:

Aspiration with the syringe and the Dominant Flex suction pump achieved the highest flows, whereas aspiration with the Pump MAX was significantly lower (P < .001). Resistors in the aspiration system (tubing, connectors, and so forth) restricted flows, especially when the resistance of the catheter was small (due to its large diameter) and the connected resistors became the predominant resistance (P < .001). The syringe achieved an average vacuum pressure of –90 kPa, and the resulting flow was constant during almost the entire procedure of filling the syringe.

CONCLUSIONS:

Sixty-milliliter VacLok vacuum pressure syringes and the Dominant Flex suction pump achieved high and constant flows likely sufficient to reverse blood flow during thrombectomy with an 8F sheath or balloon-guide catheter in the ICA and modern distal aspiration catheters in the MCA. The Pump MAX aspiration pump is dedicated for use with distal aspiration catheters and is unlikely to reverse blood flow in the ICA and MCA without balloon protection.

Treatment of Distal Anterior Cerebral Artery Aneurysms with Flow-Diverter Stents: A Single-Center Experience [INTERVENTIONAL]

BACKGROUND AND PURPOSE:

Flow diversion for aneurysms beyond the circle of Willis is still debated. Our aim was to evaluate the safety and efficacy of flow diversion treatment of distal anterior cerebral artery aneurysms.

MATERIALS AND METHODS:

Consecutive patients with distal anterior cerebral artery aneurysms treated from January 2014 to October 2017 were evaluated retrospectively with prospectively maintained data. Treatment was performed only for unruptured or recanalized aneurysms after coiling. Technical feasibility, procedural complications, aneurysm occlusion (O'Kelly-Marotta grading scale), and clinical outcome were evaluated.

RESULTS:

Fifteen patients were included in the study, with 17 distal anterior cerebral artery saccular aneurysms treated with flow-diverter stents. Mean aneurysm size was 4.25 ± 3.9 mm; range, 2–9 mm. Flow diversion was used as retreatment among 6 previously coiled aneurysms (5 ruptured and coiled in the acute phase, and 1 unruptured and recanalized). Stent deployment was technically successful in all cases. During the perioperative period, 1 patient experienced a transient minor stroke (6%), whereas 2 patients reported acute in-stent thrombosis with disabling ischemic complications (13%). Fourteen patients and 16 aneurysms were available during a mean radiologic follow-up of 12 months (range, 3–24 months). Overall, 12 (75%) aneurysms were completely occluded (O'Kelly-Marotta grading scale score D), 1 aneurysm (6%) showed near-complete occlusion (O'Kelly-Marotta grading scale score C), and 3 aneurysms (19%) were incompletely occluded (O'Kelly-Marotta grading scale, score B). All 6 aneurysms previously coiled were completely occluded after flow diversion, whereas 70% of aneurysms treated with flow diverters alone showed complete/near-complete occlusion (O'Kelly-Marotta grading scale C–D). There were no cases of aneurysm rupture, in-stent occlusion, or retreatment during long-term follow-up.

CONCLUSIONS:

Treatment of distal anterior cerebral artery aneurysms with flow-diverter stents is feasible and effective, with high rates of aneurysm occlusion. Flow diversion plus coiling, in the retreatment of lesions previously coiled, allowed higher rates of occlusion compared with flow diverters alone. However, the risk of ischemic complications is not negligible, and flow-diversion treatment should be evaluated only for aneurysms not amenable to simple coil embolization.

Differentiating Atypical Hemangiomas and Metastatic Vertebral Lesions: The Role of T1-Weighted Dynamic Contrast-Enhanced MRI [SPINE]

BACKGROUND AND PURPOSE:

Vertebral hemangiomas are benign vascular lesions that are almost always incidentally found in the spine. Their classic typical hyperintense appearance on T1- and T2-weighted MR images is diagnostic. Unfortunately, not all hemangiomas have the typical appearance, and they can mimic metastases on routine MR imaging. These are generally referred to as atypical hemangiomas and can result in misdiagnosis and ultimately additional imaging, biopsy, and unnecessary costs. Our objective was to assess the utility of dynamic contrast-enhanced MR imaging perfusion in distinguishing vertebral atypical hemangiomas and malignant vertebral metastases. We hypothesized that permeability and vascular density will be increased in metastases compared with atypical hemangiomas.

MATERIALS AND METHODS:

Consecutive patients from 2011 to 2015 with confirmed diagnoses of atypical hemangiomas and spinal metastases from breast and lung carcinomas with available dynamic contrast-enhanced MR imaging were analyzed. Time-intensity curves were qualitatively compared among the groups. Perfusion parameters, plasma volume, and permeability constant were quantified using an extended Tofts 2-compartment pharmacokinetic model. Statistical significance was tested using the Mann-Whitney U test.

RESULTS:

Qualitative inspection of dynamic contrast-enhanced MR imaging time-intensity curves demonstrated differences in signal intensity and morphology between metastases and atypical hemangiomas. Quantitative analysis of plasma volume and permeability constant perfusion parameters showed significantly higher values in metastatic lesions compared with atypical hemangiomas (P < .001).

CONCLUSIONS:

Our data demonstrate that plasma volume and permeability constant perfusion parameters and qualitative inspection of contrast-enhancement curves can be used to differentiate atypical hemangiomas from vertebral metastatic lesions. This work highlights the benefits of adding perfusion maps to conventional sequences to improve diagnostic accuracy.

Percutaneous CT-Guided Biopsies of the Cervical Spine: Technique, Histopathologic and Microbiologic Yield, and Safety at a Single Academic Institution [SPINE]

BACKGROUND AND PURPOSE:

Cervical spine biopsies can be challenging due to the anatomy and the adjacent critical structures. Percutaneous image-guided biopsies can obviate the need for an open biopsy, however there have been few studies looking at the approaches, safety, and efficacy of percutaneous cervical spine biopsies. This retrospective study evaluated technical considerations, histopathologic and microbiologic yield, and safety in CT-guided cervical bone biopsies.

MATERIALS AND METHODS:

A retrospective review of cervical bone and/or bone/disc biopsies performed from January 2010 to January 2017 was included in this study. Clinical diagnosis and indication, patient demographics, biopsy location, biopsy needle type, technical approach, lesion size, dose-length product, conscious sedation details, complications, and diagnostic histopathologic and/or microbiologic yield were recorded for each case and summarized.

RESULTS:

A total of 73 patients underwent CT-guided cervical bone biopsies. Fifty-three percent (39/73) were for clinical/imaging concern for infection and 47% (34/73) were for primary tumors or metastatic disease. Thirty-four percent (25/73) were of the inferior cervical spine (ie, C6 and C7). A sufficient sample was obtained for histopathologic and microbiologic analyses in 96% (70/73) of the biopsies. Forty-six percent (18/39) of those samples taken for infection had positive cultures. Two intraprocedural complications occurred in which the patients became hypotensive during the procedure without long-term complications.

CONCLUSIONS:

Percutaneous CT-guided biopsy of the cervical spine is an effective and safe procedure with high diagnostic yield and can obviate open procedures for histopathologic and microbiologic analyses of patients with clinical and imaging findings concerning for infection or primary and metastatic osseous lesions.

Anatomic and Angiographic Analyses of Ophthalmic Artery Collaterals in Moyamoya Disease [EXTRACRANIAL VASCULAR]

BACKGROUND AND PURPOSE:

Moyamoya disease is a progressive neurovascular pathology defined by steno-occlusive disease of the distal internal carotid artery and associated with the development of compensatory vascular collaterals. The etiology and exact anatomy of vascular collaterals have not been extensively studied. The aim of this study was to describe the anatomy of collaterals developed between the ophthalmic artery and the anterior cerebral artery in a Moyamoya population.

MATERIALS AND METHODS:

All patients treated for Moyamoya disease from 2004 to 2016 in 4 neurosurgical centers with available cerebral digital subtraction angiography were included. Sixty-three cases were evaluated, and only 38 met the inclusion criteria. Two patients had a unilateral cervical internal carotid occlusion that limited analysis of ophthalmic artery collaterals to one hemisphere. This study is consequently based on the analysis of 74 cerebral hemispheres.

RESULTS:

Thirty-eight patients fulfilled the inclusion criteria. The most frequently encountered anastomosis between the ophthalmic artery and cerebral artery was a branch of the anterior ethmoidal artery (31.1%, 23 hemispheres). In case of proximal stenosis of the anterior cerebral artery, a collateral from the posterior ethmoidal artery could be visualized (16 hemispheres, 21.6%). One case (1.4%) of anastomosis between the lacrimal artery and the middle meningeal artery that permitted the vascularization of a middle cerebral artery territory was also noted.

CONCLUSIONS:

Collaterals from the ophthalmic artery are frequent in Moyamoya disease. Their development depends on the perfusion needs of the anterior cerebral artery territories. Three other systems of compensation could be present (callosal circle, leptomeningeal anastomosis, and duro-pial anastomoses).

Reductive decolorization of azo dyes via in situ generation of green tea extract-iron chelate

Abstract

In this study, rapid decolorization of azo dyes was achieved by in situ-generated green tea extract-iron (GTE-Fe) chelate for the first time. When changing reaction conditions from the aerobic condition to the anaerobic condition, the decolorization efficiencies of two azo dyes, i.e., acid orange 7 (AO7) and acid black 1 (AB1), increased from 46.38 and 83.17 to 90.13 and 95.37%, respectively. The recalcitrant AO7 was then selected as the targeting pollutant in subsequent optimization and mechanism studies. Experimental evidences showed that the initial concentrations of AO7, Fe(III), and GTE are the key factors to optimize the decolorization efficiency. Further characterization studies by spectroscopic analysis, including FESEM, FTIR, and XPS, suggested that the major mechanism of AO7 decolorization is the nucleophilic attack of the oxygen in green tea polyphenols (GTP), and this attack could be facilitated by the organometal chelation. This study provided an efficient and environmental friendly strategy to decolorize azo dyes via in situ generation of the GTE-Fe chelate, as well as its mechanistic insights, shedding lights on in situ remediation of azo dye pollution.

Graphical abstract

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Stochastic convergence of renewable energy consumption in OECD countries: a fractional integration approach

Abstract

In this article, we have examined the hypothesis of convergence of renewable energy consumption in 27 OECD countries. However, instead of relying on classical techniques, which are based on the dichotomy between stationarity I(0) and nonstationarity I(1), we consider a more flexible approach based on fractional integration. We employ both parametric and semiparametric techniques. Using parametric methods, evidence of convergence is found in the cases of Mexico, Switzerland and Sweden along with the USA, Portugal, the Czech Republic, South Korea and Spain, and employing semiparametric approaches, we found evidence of convergence in all these eight countries along with Australia, France, Japan, Greece, Italy and Poland. For the remaining 13 countries, even though the orders of integration of the series are smaller than one in all cases except Germany, the confidence intervals are so wide that we cannot reject the hypothesis of unit roots thus not finding support for the hypothesis of convergence.

Anesthesia for collagenase clostridium histolyticum injection in patients with dupuytren disease: A cohort analysis.

Procedural pain is one of the most common adverse effects reported by patients with Dupuytren disease treated with collagenase clostridium histolyticum (CCH). The aim of this study was to assess the effectiveness of wrist block prior to CCH injection in reducing procedural pain and analyze its impact on adverse effects. We performed a prospective, single-centre study in which we compared two groups of patients in a consecutive cohort. In the first group (NO-BLOCK), wrist block was only performed before finger extension, while in the second group (BLOCK) it was performed before CCH injection and finger extension.

Nicorandil reduces burn wound progression by enhancing skin blood flow

We assessed whether nicorandil, an adenosine triphosphate-sensitive K+ channel opener, reduces burn wound progression in a rat comb burn model. A total of 24 rats were used. Following thermal injury, one dose of nicorandil (10 or 30 mg/kg) was administered intragastrically twice-daily for 3 days. At days 1 and 3 after injury, skin was harvested for histopathologic examination and protein isolation. Rats treated with the 10 mg/kg and 30 mg/kg doses of nicorandil exhibited significantly increased tissue survival in the zone of stasis at days 1 and 3 after injury.

Evolution of an evidence based supermicrosurgery simulation training curriculum: a systematic review

BackgroundSupermicrosurgery (SM) involves operating on vessels with calibers from 0.3-0.8 millimeters. Supermicrosurgery requires skills beyond those of conventional microsurgery. Current microsurgery courses do not prepare a junior surgeon for such a challenge. Several models have been developed to assist in the early learning curve, but their true purpose, benefit and validation have not been addressed. This systematic literature review summarizes the existing SM simulation models, and their likely impact on microsurgery training for small-caliber vessel-based procedures is assessed.

Flap choice does not affect complication rates or functional outcomes following extremity soft tissue sarcoma reconstruction

Flap reconstruction plays an essential role in facilitating limb preservation in patients with extremity soft tissue sarcoma (ESTS). However, the effect of flap choice on the rates of post-operative complications and functional outcomes has not been clearly established. This study directly compares the outcomes of free and pedicled flap reconstructions in ESTS patients.

Treatment of dopplerable nummular headache with minimally invasive arterectomy under local anesthesia

The objective of the current study is to elucidate the potential role of surgery in the treatment of nummular headache.

The ecological competition and grazing reverse the effects of sulfamethoxazole on plankton: a case study on characterizing community-level effect

Abstract

The toxic effects of sulfamethoxazole (SMX) on densities of two algae, Platymonas helgolandica var. tsingtaoensis, Isochrysis galbana, and of a rotifer, Brachionus plicatilis, were tested by the population and community experiments. Two endpoints, the carrying capacity and the densities array of community in steady state (DACS), were used to characterize the toxic effects at a population level and a community one, respectively. The results showed that the carrying capacity of P. helgolandica var. tsingtaoensis and B. plicatilis did not decline significantly in population test when the concentration of SMX was lower than 6.0 mg L⁻¹ and 12.0 mg L⁻¹, respectively. However, I. galbana was sensitive to SMX and had presented toxic effect at 3.0 mg L⁻¹. By extrapolation of toxic effect at a population level to a community one, a derived community-NOEC was 3.0 mg L⁻¹, representing an inference from data of toxic effects at population level. In community experiment, when the customized community was in steady state, the density of I. galbana increased as a whole with SMX concentration in the range of tested concentration (0–144 mg L⁻¹), while that of P. helgolandica var. tsingtaoensis assumed the trend of a reversed "v" in this range. Only the density of B. plicatilis decreased with SMX concentration. With the DACS as endpoint, a NOEC for the customized community was determined to be 6.0 mg L⁻¹. This indicates that interspecific interactions can reverse the toxic effects of SMX on phytoplankton. The DACS was reliable and stable, serving as the endpoints in assessment of the effects of the pollutants on the ecosystems.

Erratum

Why Philosophers should do Semantics (and a bit of syntax too): a Reply to Cappelen

Abstract

In this paper, I address a series of arguments recently put forward by Cappelen Review of Philosophy and Psychology 8(4): 743–762 (2017) to the effect that philosophers should not do formal semantics or be concerned with the "minutiae of natural language semantics". He offers two paths for accessing his ideas. I argue that his arguments fail in favour of the first and cast some doubt on the second in so doing. I then proffer an alternative conception of why exactly philosophers should continue to do formal linguistics which includes both semantics and syntax.

Oocyte atresia in WT (HdrR) and P53 (−/−) medaka (Oryzias latipes) exposed to UVA

Publication date: Available online 12 April 2018
Source:Journal of Photochemistry and Photobiology B: Biology
Author(s): Alaa El-Din H. Sayed, Rania F. Ismail, Hiroshi Mitani
The negative effects of ambient ultraviolet (UVA) on the water environment have been recently highlighted; UVA can create deleterious effects by stimulating stress on pelagic organisms. Little is known about UVA effects on oocyte characteristics of female fish. In the present study we explored the effects of exposure to ecologically relevant levels of simulated UVA radiation on ovaries of two major strains WT (HdrR) and P53 (−/−) of medaka (Oryzias latipes) mature female. Fish were assigned to control and three UVA-exposed groups as (15 min, 30 min, and 60 min/day) for three days and sample selection was 24 h and 14 days after exposure. Histological alterations and oocyte atresia percentage were analyzed in the UVA-exposed fish compared to control. Alteration comprised hyperthrophied follicular cells with increased thickness, breakdown of egg chorion (zona radiata), damage of cortical alveoli, and distorted nucleus and cytoplasm. The atresia percentages significantly increased with higher UVA exposure dose and time for both the wild type and the p53 deficient fish. The wild type displayed significantly higher oocyte atresia percentage than the p53 mutant. These results suggested that UVA exposure provoked histological alterations in both p53 and WT medaka oocytes leading to follicular atresia, which reduce female reproductive ability and larval production. UVA oocyte response showed p53 dependent and independent histological alteration, however, the p53 mutant was less sensitive to UVA than the wild type in medaka fish.

UV stabilization of wood by nano metal oxides dispersed in propylene glycol

Publication date: Available online 12 April 2018
Source:Journal of Photochemistry and Photobiology B: Biology
Author(s): Sreeja Nair, B.N. Giridhar, Krishna K. Pandey
Nanoparticles of some of the metal oxides are known to have high UV protective efficiency. The UV filtering efficiency of nanoparticles invariably depends on their size and stability in the dispersion. In the present work, a stable dispersion of nanoparticles of three metal oxides, zinc oxide (ZnO), cerium oxide (CeO2) and titanium dioxide (TiO2), was prepared in propylene glycol (PG) using ultrasonication. The method is easy and useful as no additional surfactant or dispersant is needed. The particle size and its distribution was confirmed by Scanning Electron Microscopy and Dynamic Light Scattering. The stability of dispersion was assessed by UV–visible absorption spectroscopy. The UV stability of wood surfaces of Wrightia tinctoria coated with nanodispersions of ZnO, CeO2 and TiO2 was evaluated under laboratory conditions in an accelerated weathering tester. Changes in the colour and FTIR spectra of exposed specimens were measured periodically. Rapid colour darkening (yellowing) was observed in uncoated and PG coated specimens. In contrast, nanodispersion coated specimens prevented photo-yellowing considerably with significant reduction in colour changes examined by CIE L*, a*, b* and ΔE*. Increase in concentration of nanoparticles in the dispersion imparted higher resistance to UV induced degradation. However, increased concentration of nanoparticles reduced the transparency of the coating. FTIR analysis indicated rapid degradation of lignin in uncoated and PG coated specimens due to UV exposure. Coating of wood surfaces with nanodispersions restricted lignin degradation. The study also demonstrates the potential of propylene glycol as a dispersant for developing stable and efficient UV protective nanodispersions for wood coating.

Ca2+ stabilization of respiratory Complex I from Escherichia coli

Abstract

Stability of the membrane-bound and purified H⁺-translocating NADH:ubiquinone oxidoreductase, Complex I, was studied. The loss of the enzyme activity is strongly increased by alkaline pH and dilution of the sample. Complex I inactivation is prevented specifically by a low concentration of Ca²⁺ and/or an intracellular stabilization factor (ISF). The action of both, Ca²⁺ and ISF, on Complex I stability is interdependent. The data are discussed in terms of a release of structural Ca²⁺ as a reason for Complex I decay and an effect of ISF on the affinity and/or accessibility of Ca²⁺ binding site.

The way is the goal: how SecA transports proteins across the cytoplasmic membrane in bacteria1

Abstract

In bacteria, translocation of most soluble secreted proteins (and outer membrane proteins in Gram-negative bacteria) across the cytoplasmic membrane by the Sec machinery is mediated by the essential ATPase SecA. At its core, this machinery consists of SecA and the integral membrane proteins SecYEG, which form a protein conducting channel in the membrane. Proteins are recognised by the Sec machinery by virtue of an internally-encoded targeting signal, which usually takes the form of an N-terminal signal sequence. In addition, substrate proteins must be maintained in an unfolded conformation in the cytoplasm, prior to translocation, in order to be competent for translocation through SecYEG. Recognition of substrate proteins occurs via SecA—either through direct recognition by SecA or through secondary recognition by a molecular chaperone that delivers proteins to SecA. Substrate proteins are then screened for the presence of a functional signal sequence by SecYEG. Proteins with functional signal sequences are translocated across the membrane in an ATP-dependent fashion. The current research investigating each of these steps is reviewed here.

Biological control of Meloidogyne javanica on tomato with Dazitol® and soil solarization

Abstract

Pot and greenhouse trials were conducted for the management of root-knot nematode, Meloidogyne javanica, infestation in tomato. Growth parameters, gall index, soil, and root nematode populations were measured to assess the effect of a novel bio-pesticide (Dazitol®), made from mustard oil and oleoresin of Capsicum, on plant growth and nematode reproduction. Data generated within the pot experiment showed that the tested bio-pesticide did not improve plant growth, but it reduced significantly root-knot nematode damage resulting in a decrease in gall index and root (91%) and soil (62%) population of M. javanica compared with untreated plants. The greenhouse experiment showed that Mocap® and Dazitol® decreased nematode incidence significantly (P < 0.05) on tomato. The result of this study suggested that the best nematode control was obtained by combining soil solarization with chemical or botanical nematicides as an integrated pest management approach.

Biosorption of strontium ions from simulated high-level liquid waste by living Saccharomyces cerevisiae

Abstract

In this study, the Saccharomyces cerevisiae (S. cerevisiae) was modified by γ-ray. The RNA-seq results reflect that the high γ-ray energies could change some gene fragments, such as deletion, recombination, and mutation. The biosorption of strontium ions (Sr²⁺) to different types of S. cerevisiae (S. cerevisiae (K-0), modified S. cerevisiae (Y-7), and non-living S. cerevisiae (H-K)) from the simulated high-level liquid waste (S-HLLW) was assessed at different experimental conditions. The sorption experimental results show that, under an appropriate condition, γ-ray radiation can enhance its biosorption capacity slightly of Sr²⁺ to S. cerevisiae. The maximum metal uptake and efficiency of Y-7 under S-HLLW were 11.656 mg g⁻¹ and 37.91% at 32 h (wet weight), respectively. They decreased to 9.46 mg g⁻¹ and 30.76% under radiation conditions. SEM-EDX and TEM analysis indicates that Sr²⁺ was adsorbed both on the cellular surface and the inner parts of the cells. Our experimental results fit well to the Langmuir and Freundlich model isotherms (r² > 0.94), and the maximum biosorption capacity values reached q_max > 24.74 mg g⁻¹ at 32 °C. Negative values of ΔG⁰ and positive values of ΔH⁰ were observed, indicating the spontaneous and endothermic nature of Sr²⁺ biosorption on modified S. cerevisiae. The biosorption kinetics follow a pseudo-second-order equation at 32 °C (r² > 0.94). The desorption efficiency of Sr²⁺ adsorbed onto Y-7 was 7.65 ± 0.52%, 76.51 ± 2.13%, and 65.62 ± 2.42% by deionized water, 1 M HCl, and 0.1 M EDTA-Na, respectively. However, they were lower than H-K (18.82, 83.32, and 73.32%). Our findings demonstrate that living S. cerevisiae (Y-7) is a promising sorbent material for the treatment of radioactive process streams.

The heterogeneous effects of urbanization and income inequality on CO 2 emissions in BRICS economies: evidence from panel quantile regression

Abstract

This paper empirically examines the effects of urbanization and income inequality on CO₂ emissions in the BRICS economies (i.e., Brazil, Russia, India, China, and South Africa) during the periods 1994–2013. The method we used is the panel quantile regression, which takes into account the unobserved individual heterogeneity and distributional heterogeneity. Our empirical results indicate that urbanization has a significant and negative impact on carbon emissions, except in the 80^th, 90^th, and 95^th quantiles. We also quantitatively investigate the direct and indirect effect of urbanization on carbon emissions, and the results show that we may underestimate urbanization's effect on carbon emissions if we ignore its indirect effect. In addition, in middle- and high-emission countries, income inequality has a significant and positive impact on carbon emissions. The results of our study indicate that in the BRICS economies, there is an inverted U-shaped environmental Kuznets curve (EKC) between the GDP per capita and carbon emissions. The conclusions of this study have important policy implications for policymakers. Policymakers should try to narrow the income gap between the rich and the poor to improve environmental quality; the BRICS economies can speed up urbanization to reduce carbon emissions, but they must improve energy efficiency and use clean energy to the greatest extent in the process.

Can tumor coverage evaluated 24 h post-radiofrequency ablation predict local tumor progression of liver metastases?

Abstract

Purpose

To assess the predictive value for local tumor progression (LTP) of geometrical tumor coverage using the contrast-enhanced (ce-)CT images acquired before and within 24 h after radiofrequency (RF) ablation.

Methods

Twenty patients (6 male and 14 female, median age 62 years) with 45 focal hypovascular liver metastases (16 colorectal carcinoma, 3 melanoma and 1 breast carcinoma) underwent RF ablation under CT-guidance and received a ce-PET/CT scan within 24 h post-procedure. Pre- and post-ablation ce-CT-images were aligned using an interactive procedure and used to verify the tumor coverage of the RF ablation. Results were correlated to LTP as recorded during follow-up performed every 2–3 months after the intervention (mean follow-up of 110 weeks) and compared to standard reading performed by three readers of the ce-CT images.

Results

Eleven tumors (25%) showed LTP during the follow-up period. One lesion, which did not show LTP, was excluded from analysis due to the poor quality of the alignment. For the remaining, 29 (66%) tumors were completely covered by the ablation zone, 9 (20%) were not, and for 6 (14%) tumors the edges coincided with the edge of the ablation zone. The sensitivity, specificity, PPV and NPV for LTP of having incomplete tumor coverage or no apparent ablative margin versus standard reading of ce-CT were 100, 88, 73 and 100% versus 42, 88, 58 and 82%, respectively.

Conclusions

Verifying the tumor coverage of liver metastases by an ablation zone through alignment of pre- and early post-ablation ce-CT images has a high predictive value for LTP.

Evaluation of the Noma Disease Burden Within the Noma Belt

This study estimates the disease burden of noma, an opportunistic infection of the face that occurs in the setting of extreme poverty.

The Protection of Augmented Tip Flap Technique for Tip Camouflage

This Surgical Pearl presents the protection of augmented tip (PAT) flap technique for preventing tip graft visibility in rhinoplasty.

Serum folate and cobalamin levels and urinary dimethylarsinic acid in US children and adults

Abstract

Nutritional status could affect arsenic metabolism and toxicity in the general population chronically exposed to low levels of inorganic arsenic. In this study, we examined the association of serum folate and cobalamin with urinary concentrations of dimethylarsinic acid (DMA), the most abundant metabolite of inorganic arsenic measured in urine, in children and adults who participated in the 2003–2006 US National Health and Nutrition Examination Surveys. A total of 1161 children (aged 6–19 years) and 1938 adults (aged 20–85 years) were analyzed for the association using multivariate general linear models, adjusting for potential confounders. We observed a positive association between serum levels of folate and cobalamin and creatinine-corrected urinary concentrations of DMA in both children and adults. Furthermore, serum levels of folate and cobalamin were inversely associated with homocysteine (Hcy). These results suggest that dietary intake of folate and cobalamin may exhibit protective functions against arsenic toxicity by increasing arsenic metabolism to the less toxic metabolite DMA and decreasing serum levels of Hcy.

Rituximab in Refractory Chronic Spontaneous Urticaria: An Encouraging Therapeutic Approach

Background: Chronic spontaneous urticaria (CSU) is a frequent mast cell-driven disease that affects approximately 0.5–1% of the population. Antihistamines are currently the drugs of choice in patients with CSU. Omalizumab has been shown to be very effective in CSU and has been recently approved as second-line therapy. However, although its introduction has markedly improved the therapeutic possibilities for CSU, there is still a hard core of patients who do not respond and require effective treatment. Methods: We report the case of a patient who achieved an 8-month remission of refractory CSU following the use of rituximab, and perform a review of the literature regarding the use of rituximab in CSU. Results: There was a remarkable improvement in her CSU after the administration of rituximab maintained over time. Conclusion: Rituximab is a chimeric murine/human monoclonal antibody directed against CD20, which depletes memory B-lymphocytes that are necessary for autoantibody production. The abrogation of the autoantibody production is the proposed mechanism by which it may alleviate the symptoms of CSU.
Skin Pharmacol Physiol 2018;31:184–187

Sulfur extraction from liquid fuels using trihexyl(tetradecyl)phosphonium tetrafluoroborate: as promising solvent

Abstract

Sulfur extraction from fuel is essential to be done for environmental and industrial point of view. Extractive desulfurization (EDS) is one of the most promising techniques in order to achieve legislative sulfur content requirements. Among numerous extractants and solvents, ionic liquids (ILs) are more capable due to their desirable green solvent properties. This work demonstrated that trihexyl(tetradecyl)phosphonium tetrafluoroborate ([THTDP]BF₄) was synthesized, characterized, and employed as extraction solvent for extraction of dibenzothiophene (DBT), thiophene, benzothiophene, and other alkyl-substituted derivatives of sulfur from liquid fuel. Molecular confirmation and purity of synthesized ([THTDP]BF₄) were analyzed with FTIR, Raman, NMR, EPR, UV, TG/DSC, and XRD analyses. Also, physical properties of ([THTDP]BF₄) were carried out. The effects of extraction time, temperature, sulfur compounds, ultra-sonication, and ([THTDP]BF₄) recycling/regeneration on DBT removal from liquid fuel were also examined. DBT removal in n-dodecane was 92.6% using EDS with mass ratio (1:1) in 30 min at 30 °C under the mild reaction conditions. ([THTDP]BF₄) could be reused up to ten cycles for sulfur extraction and regenerated for few more cycles with good DBT removal ability. Also, the sulfur extraction from real fuels and multistage extraction performance were tested. The experimental data and results provided in this article discover the remarkable understandings of tetrafluoroborate-based phosphonium ionic liquids as promising solvent for EDS.

Learning-based endovascular navigation through the use of non-rigid registration for collaborative robotic catheterization

Abstract

Purpose

Endovascular intervention is limited by two-dimensional intraoperative imaging and prolonged procedure times in the presence of complex anatomies. Robotic catheter technology could offer benefits such as reduced radiation exposure to the clinician and improved intravascular navigation. Incorporating three-dimensional preoperative imaging into a semiautonomous robotic catheterization platform has the potential for safer and more precise navigation. This paper discusses a semiautonomous robotic catheter platform based on previous work (Rafii-Tari et al., in: MICCAI2013, pp 369–377. https://doi.org/10.1007/978-3-642-40763-5_46, 2013) by proposing a method to address anatomical variability among aortic arches. It incorporates anatomical information in the process of catheter trajectories optimization, hence can adapt to the scale and orientation differences among patient-specific anatomies.

Methods

Statistical modeling is implemented to encode the catheter motions of both proximal and distal sites based on cannulation data obtained from a single phantom by an expert operator. Non-rigid registration is applied to obtain a warping function to map catheter tip trajectories into other anatomically similar but shape/scale/orientation different models. The remapped trajectories were used to generate robot trajectories to conduct a collaborative cannulation task under flow simulations. Cross-validations were performed to test the performance of the non-rigid registration. Success rates of the cannulation task executed by the robotic platform were measured. The quality of the catheterization was also assessed using performance metrics for manual and robotic approaches. Furthermore, the contact forces between the instruments and the phantoms were measured and compared for both approaches.

Results

The success rate for semiautomatic cannulation is 98.1% under dry simulation and 94.4% under continuous flow simulation. The proposed robotic approach achieved smoother catheter paths than manual approach. The mean contact forces have been reduced by 33.3% with the robotic approach, and 70.6% less STDEV forces were observed with the robot.

Conclusions

This work provides insights into catheter task planning and an improved design of hands-on ergonomic catheter navigation robots.

Treatment of dopplerable nummular headache with minimally invasive arterectomy under local anesthesia

Publication date: Available online 12 April 2018
Source:Journal of Plastic, Reconstructive & Aesthetic Surgery
Author(s): Bahman Guyuron, James Gatherwright, Deborah Reed, Hossein Ansari, Rebecca Knackstedt
ObjectiveThe objective of the current study is to elucidate the potential role of surgery in the treatment of nummular headache.BackgroundNummular headache is a disorder in which pain is localized to a specific area. Treatment has historically been medical, with the recent addition of nerve blocks and botox injection with equivocal results.DesignForty-nine patients were identified using the International Classification of Headache Disorders, third edition version β. Patients were asked to identify their area of maximal pain. Patients who had an associated Doppler signal within the area of pain underwent surgical arterectomy using local anesthesia. Pre- and post-operative headache frequency, severity, duration, and headache-free days were analyzed.ResultsThere were a total of 49 patients included in the study (42F:7M) with an average age of 45 years (21 – 65). The average follow-up was 16 months with a range of 8 – 33 months. There was a significant reduction in the frequency (-10.7 days; p < 0.001), severity (-3.5; p < 0.001) and duration (-0.3 hours; p=0.4). There was a significant increase in the number of headache-free days per month (10 vs. 21; p < 0.001). Headache index decreased by 39.6%, from an average of 378.6 to 228.4 (p<0.05). Twelve patients (24.5%) were NH free and able to discontinue their medications. There were no complications identified within the follow-up period.ConclusionsNummular headaches, while rare, can be associated with significant disability despite current treatment modalities. In select patients, surgical arterectomy is a safe, minimally invasive, and effective treatment for nummular headache.

Flap choice does not affect complication rates or functional outcomes following extremity soft tissue sarcoma reconstruction

Publication date: Available online 12 April 2018
Source:Journal of Plastic, Reconstructive & Aesthetic Surgery
Author(s): Jelena Slump, Stefan O.P. Hofer, Peter C. Ferguson, Jay S. Wunder, Anthony M. Griffin, Harald J. Hoekstra, Esther Bastiaannet, Anne C. O'Neill
BackgroundFlap reconstruction plays an essential role in facilitating limb preservation in patients with extremity soft tissue sarcoma (ESTS). However, the effect of flap choice on the rates of post-operative complications and functional outcomes has not been clearly established. This study directly compares the outcomes of free and pedicled flap reconstructions in ESTS patients.MethodsTwo hundred and sixty-six patients who underwent flap reconstruction following ESTS resection were included. Associations between flap type and complications were determined using logistic regression analyses. Functional outcome was evaluated using the Toronto Extremity Salvage Score (TESS) and the Musculoskeletal Tumor Society Scales (MSTS).ResultsThere was no significant difference between complication rates in the pedicled and free flap groups (32% vs 38%, p=0.38). In the lower limb pedicled flaps had similar complication rates as free flaps on univariate analysis (OR 1.12, 95%CI 0.56-2.26, p=0.75). Conversely in the upper limb pedicled flaps were associated with fewer complications on univariate analysis (OR 0.31, 95%CI 0.11-0.86, p=0.03), but this was not significant on multivariate analysis (OR 0.45, 95%CI 0.13-1.59, p=0.22). Obesity was a strong predictor of complications in the upper limb group on multivariate analysis (BMI≥30 OR 7.01, 95%CI 1.28-38.51, p=0.03). There was no significant difference in functional outcomes between both flap groups in either upper or lower limbs.ConclusionsPost-operative complications and functional outcomes for patients undergoing free and pedicled flaps are similar in ESTS reconstruction. Selecting the most suitable reconstructive option in each individual case is paramount to preserving function while minimizing post-operative morbidity.

Does intraoperative navigation improve the accuracy of mandibular angle osteotomy: comparison between augmented reality navigation, individualised templates, and free-hand techniques

Publication date: Available online 11 April 2018
Source:Journal of Plastic, Reconstructive & Aesthetic Surgery
Author(s): Ming Zhu, Fei Liu, Chaozheng Zhou, Li Lin, Yan Zhang, Gang Chai, Le Xie, Fazhi Qi, Qingfeng Li
BackgroundAugmented reality (AR)-based navigation surgery has evolved to be an advanced assisted technology. The aim of this study is to manifest the accuracy of AR navigation for the intraoperative mandibular angle osteotomy by comparing the navigation with other interventional techniques.MethodsA retrospective study was conducted with 93 post-surgical patients with mandibular angle hypertrophy admitted at our plastic and reconstructive surgery department between September 2011 and June 2016. Thirty-one patients received the osteotomy conducted by navigation system based on augmented reality (AR group), 28 patients were received osteotomy conducted by the individualised templates (IT group), and the remaining 34 patients received osteotomy performed by free hand (free-hand group). The postoperative computed tomography (CT) images were reviewed and analysed by comparing with presurgical planning generated by three-dimensional (3D) software. The preparation time, cutting time, whole operating time, and discrepancy of osteotomy lines were measured.ResultsThe preparation time was much shorter in the free-hand group compared with the AR group and the IT group (P<0.01). However, no significant difference in the whole operating time was observed among the three groups (P>0.05). In addition, the discrepancy of osteotomy lines was lower in the AR group and in the IT group than in the free-hand group (P<0.01).Conclusionhe navigation system based on AR has higher accuracy, more reliability, and better user friendliness for some particular clinical procedures than for other techniques, which has a promising clinical prospect.

A systematic review and meta-analysis of comparison of autologous costal cartilage and alloplastic materials in rhinoplasty

Publication date: Available online 11 April 2018
Source:Journal of Plastic, Reconstructive & Aesthetic Surgery
Author(s): Xuebing Liang, Keming Wang, Sunitha Malay, Kevin C. Chung, Jiguang Ma
BackgroundBoth autologous costal cartilage (ACC) and alloplastic materials are widely used in rhinoplasty. However, there is controversy regarding which material can offer the ideal outcome and fewer complications.ObjectiveThe authors review current literature to evaluate complication and satisfaction rates with different materials in rhinoplasty.MethodsA comprehensive literature search was conducted in Embase and Pubmed of articles published through April 14, 2017. We included only articles that used ACC, silicone, Medpor, Gore-tex or a combination of autologous and alloplastic materials in rhinoplasty. The primary outcomes analysed were complications and post-operative satisfaction. After data extraction, meta-analysis using random effect model was performed to summarize outcome parameters among different implant types.ResultsFifty-three articles met inclusion criteria and were included in the meta-analysis. The overall complication rate of ACC was 14%, which was higher compared with other implants. However, ACC was more commonly used in revision rhinoplasty. Medpor was associated with low overall complication rates (6%) and good aesthetic and functional outcomes.ConclusionsOur analysis of available evidence suggests that ACC is preferred in revision rhinoplasty, which may explain its association with higher complication rates. In primary rhinoplasty, Medpor offered versatility in addition to low complication rates and good aesthetic and function outcomes. But its potential dramatic damage to nasal tissue made secondary surgery extremely difficult. Our findings were limited by lack of high quality evidence. Future studies with rigorous study design for head-to-head comparisons and longer follow-up are needed to establish clear guidelines for choosing the appropriate rhinoplasty graft material.

The modified bull's horn upper lip lift

Publication date: Available online 11 April 2018
Source:Journal of Plastic, Reconstructive & Aesthetic Surgery
Author(s): Yu Kit Li, Morris Ritz

Evolution of an evidence based supermicrosurgery simulation training curriculum: a systematic review

Publication date: Available online 12 April 2018
Source:Journal of Plastic, Reconstructive & Aesthetic Surgery
Author(s): Georgios Pafitanis, Mitsunaga Narushima, Takumi Yamamoto, Maria Raveendran, Damjan Veljanoski, Ali M. Ghanem, Simon Myers, Isao Koshima
BackgroundSupermicrosurgery (SM) involves operating on vessels with calibers from 0.3-0.8 millimeters. Supermicrosurgery requires skills beyond those of conventional microsurgery. Current microsurgery courses do not prepare a junior surgeon for such a challenge. Several models have been developed to assist in the early learning curve, but their true purpose, benefit and validation have not been addressed. This systematic literature review summarizes the existing SM simulation models, and their likely impact on microsurgery training for small-caliber vessel-based procedures is assessed.MethodsAn electronic literature search was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. From the literature search 90 potential articles from MEDLINE and 300 articles from other databases were identified and screened. Twenty-five studies were screened against the inclusion criteria by two independent reviewers for a final critical analysis.ResultsThirty-six articles were included in the reviewing process and 15 SM simulation-training models were identified. The simulation models were classified as non-biological or biological and as ex-vivo or in-vivo. None of these models demonstrated validity. However, critical analysis of the full-text articles established the clinical correlation of each model along with the specific skill demonstrated. A novel ladder-based curriculum was established. Further, an expert's questionnaire generated a likert scale and the clinical impact of each SM simulation training model.ConclusionThis is the first review to highlight the clinical relevance of SM models and the need for validation. Currently, a variety of training models in SM appear to enable the acquisition of specific skills, and the clinical impact of a selection is recognized in a proposed SM simulation training curriculum.

Molecular Ablation of Tumor Blood Vessels Inhibits Therapeutic Effects of Radiation and Bevacizumab

Abstract

Background

Glioblastoma (GBM) is an aggressive and highly vascular tumor with median survival below 2 years. Despite advances in surgery, radiotherapy and chemotherapy survival has improved modestly. To combat glioma vascular proliferation anti-angiogenic agents targeting vascular endothelial growth factor (VEGF) were introduced. Preclinically these agents were effective, yet they did not improve overall survival in Phase III trials. We tested the hypothesis that ganciclovir (GCV)-mediated killing of proliferating endothelial cells expressing HSV1-TK would have direct anti-tumor effects, and whether vessel ablation would affect the anti-tumor activity of anti-VEGF antibodies and radiotherapy.

Methods

Proliferating endothelial cells were eliminated using ganciclovir-mediated killing of proliferating endothelial cells expressing HSV1-TK (in Tie2-TK-IRES-GFP mice). Syngeneic NRAS/p53 (NP) gliomas were implanted into the brains of Tie2-TK-IRES-GFP mice. Endothelial proliferation activates the Tie2 promoter and HSV1-TK expression. Administration of ganciclovir kills proliferating tumor endothelial cells and slows tumor growth. The effects of endothelial cell ablation on anti-angiogenic therapy were examined using anti-VEGF antibodies or irradiation.

Results

GCV administration reduced tumor growth and vascular density, increased tumor apoptosis, and prolonged survival. Anti-VEGF antibodies or irradiation also prolonged survival. Surprisingly, combining GCV with irradiation, or with anti-VEGF antibodies, reduced their individual therapeutic effects.

Conclusion

Ganciclovir-mediated killing of proliferating endothelial cells expressing HSV1-TK, anti-VEGF antibodies, or irradiation all reduced growth of a murine glioma. However, elimination of microvascular proliferation decreased the efficacy of anti-VEGF or irradiation therapy. We conclude that, in our model, the integrity of proliferating vessels is necessary for the anti-glioma effects of anti-VEGF and radiation therapy.