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Tropical cyclones impact estuaries via a variety of mechanisms including storm surge, flooding from precipitation, high winds, and strong wave action. Prior studies have documented disturbances caused by tropical cyclones, including prolonged periods of depressed salinity from high freshwater discharge and increased or decreased dissolved oxygen concentrations from increased loading of organic matter and/or nutrients. However, most studies of disturbance and recovery in estuaries have been limited to one or a few locations or storm events, limiting generalizations about tropical cyclone impacts and characteristic patterns of ecosystem response and recovery. We analyzed responses to 59 tropical cyclones across 19 estuaries in the eastern USA by applying a new method for detecting disturbance and recovery to long-term and high-frequency measurements of salinity and dissolved oxygen from NOAA's National Estuarine Research Reserve System. We quantified disturbance occurrence, timing, recovery time, and severity. Salinity disturbances generally started earlier and lasted longer than dissolved oxygen disturbances. Estuaries usually recovered within days, but some disturbances lasted weeks or months. Recovery time was positively correlated with disturbance severity for both variables. Tropical cyclone properties (especially precipitation) and location characteristics were both related to disturbance characteristics. Our findings demonstrate the power of high-frequency, long-term, and cross-system data, when combined with appropriate statistical methods, for analyzing hurricanes across many estuaries to quantify disturbances. Estuaries are resilient to hurricanes for the variables and time periods considered. However, persistent impacts can potentially damage resources provided by estuaries, eroding future resilience if hurricanes become more frequent and severe. [ABSTRACT FROM AUTHOR]

Although certain individuals with HIV infection can stop antiretroviral therapy (ART) without viral load rebound, the mechanisms under-pinning 'post-treatment control' remain unclear. Using RNA-Seq we explored CD4 T cell gene expression to identify evidence of a mechanism that might underpin virological rebound and lead to discovery of associated biomarkers. Fourteen female participants who received 12 months of ART starting from primary HIV infection were sampled at the time of stopping therapy. Two analysis methods (Differential Gene Expression with Gene Set Enrichment Analysis, and Weighted Gene Co-expression Network Analysis) were employed to interrogate CD4+ T cell gene expression data and study pathways enriched in post-treatment controllers versus early rebounders. Using independent analysis tools, expression of genes associated with type I interferon responses were associated with a delayed time to viral rebound following treatment interruption (TI). Expression of four genes identified by Cox-Lasso (ISG15, XAF1, TRIM25 and USP18) was converted to a Risk Score, which associated with rebound (p < 0.01). These data link transcriptomic signatures associated with innate immunity with control following stopping ART. The results from this small sample need to be confirmed in larger trials, but could help define strategies for new therapies and identify new biomarkers for remission. [ABSTRACT FROM AUTHOR]

Neurotoxicity is a recognized complication with the use of Cyclosporin A (CSA) in bone marrow and organ transplantation patients. Most common symptoms are seizures and altered mental status which are usually transient. We report three cases of transient neurotoxic episodes in patients receiving CSA after a bone marrow transplant. There were reversible low-attenuation changes on CT and bright T2-weighted signal changes on MRI in the cortex and/or white matter of the cerebral hemispheres. All three patients, when given lower maintenance doses of CSA, were free of recurrent neurotoxic effects. [ABSTRACT FROM AUTHOR]

Bioconstructions such as coralligenous outcrops and maërl beds are typical Mediterranean underwater seascapes. Fine-scale knowledge on the distribution of these sensitive habitats is crucial for their effective management and conservation. In the present study, a thorough review of existing spatial datasets showing the distribution of coralligenous and maërl habitats across the Mediterranean Sea was undertaken, highlighting current gaps in knowledge. Predictive modelling was then carried out, based on environmental predictors, to produce the first continuous maps of these two habitats across the entire basin. These predicted occurrence maps for coralligenous outcrops and maërl beds provide critical information about where the two habitats are most likely to occur. The collated occurrence data and derived distribution model outputs can help addressing the challenge of developing basin-wide spatial plans and to guide cost-effective future surveys and monitoring efforts towards areas that are presently poorly-sampled. [ABSTRACT FROM AUTHOR]

Large differences in δH of primary producers between aquatic and terrestrial ecosystems are used to identify subsidies, discriminate organic matter sources, and reduce uncertainty in food web studies. Previous investigations of hydrogen isotope ratios suggest there may be predictable differences between the δH of water and organic matter for different types of primary producers. We define the difference in the net isotopic discrimination between water and bulk organic matter (om) as: Δ = ( δH − δH) ÷ (1 + δH ÷ 1,000). We summarized Δ values from published literature and we measured the δH of water and primary producers in order to compare Δ among aquatic and terrestrial primary producers. Measurements were made from three water body types (lake, river, coastal lagoon) and their associated watersheds. Although we predicted a large and equivalent net isotopic discrimination for aquatic primary producers, we found considerable variability among groups of aquatic producers. Macroalgae, benthic microalgae, and phytoplankton had more negative Δ values (i.e. greater isotopic discrimination) than both aquatic macrophytes and terrestrial vegetation. The more positive δH and hence lower Δ of terrestrial vegetation was expected due to relative increases in the heavier isotope, deuterium, during transpiration. However, the more positive values of δH and relatively low Δ in aquatic macrophytes, even submerged species, was unexpected. Marine macroalgae had high variability in δH as a group, but low variability within distinct species. Variability among types of primary producers in δH and in Δ should be assessed when hydrogen is used in isotopic studies of food webs. [ABSTRACT FROM AUTHOR]

Weak cathodal transcranial direct current stimulation (tDCS) of the human hand area modulates corticospinal excitability with a suppression of motor-evoked potentials (MEPs) evoked by transcranial magnetic stimulation (TMS). The changes in excitability persist beyond the time of stimulation if tDCS is given for several minutes and can remain stable for an hour or more. The aim of present study was to evaluate whether a long-lasting suppression of cortical excitability could be induced by prolonged cathodal tDCS (20 min of stimulation). We also explored the impact of brain-derived neurotrophic factor (BDNF) gene polymorphisms, on tDCS after-effects. Cortical excitability to single and paired-pulse TMS was evaluated both for the stimulated and contralateral hemisphere, before and up to 24 h after 20 min of cathodal tDCS. We evaluated threshold and amplitude of MEPs, short interval intracortical inhibition (SICI), and intracortical facilitation (ICF). tDCS produced a pronounced suppression of MEP amplitude that was still significant at 3 h after the end of stimulation. The BDNF genotype had not influence on tDCS after-effects. Thresholds for MEPs, SICI and ICF were not affected. No significant effect was observed in the contralateral hemisphere. Twenty minutes of cathodal tDCS is capable of inducing a long-lasting suppression of the excitability of the human motor cortex. [ABSTRACT FROM AUTHOR]

This study aimed to assess whether laparoscopic treatment for any kind of varicocele is possible after preoperative identification of refluxing veins by color Doppler ultrasound (CDUS). At the authors’ institution, 98 patients with a median age of 11.3 years (range, 7.1–16 years) were evaluated for a left varicocele. Preoperatively, all the patients underwent ultrasound scan assessment of testicular volume and CDUS to rule out reflux into the internal spermatic vein (ISV), deferential vein, or cremasteric vein. In all the patients, laparoscopic division of the spermatic artery and veins was performed as close as possible to the internal inguinal ring. The other vessels were coagulated and divided if shown to be refluxing on CDUS. Color Doppler ultrasound showed reflux only in the ISV in 87 cases (88.7%), but in both the ISV and the deferential in the remaining 11 cases (11.2%). During a median follow-up period of 18 months (range, 6–49 months), none of the authors’ patients experienced varicocele recurrence either clinically or according to CDUS scanning. The median left testicular volume increased significantly postoperatively. The proposed technique based on laparoscopic interruption of the ISV and testicular artery very close to the internal inguinal ring, meticulous CDUS assessment to rule out reflux in the deferential vein, and coagulation of refluxing deferential veins allows successful laparoscopic treatment of most varicoceles. [ABSTRACT FROM AUTHOR]

The authors report preliminary data of an Italian multicentric, retrospective study of primary testicular tumors (PTT) in childhood involving 20 Italian departments of pediatric surgery. Forty cases of PTT were observed during a 10-year period (1977-1987), with yolk-sac tumors being the most frequent (45%). Most testicular tumors were first perceived as a unilateral testicular mass. Scrotal ultrasonography represents the main diagnostic investigation, together with serum marker levels. [ABSTRACT FROM AUTHOR]

A thiol:protein disulfide oxidoreductase from bovine liver was isolated after separation from protein disulfide isomerase. The enzyme, after activation (reduction) with glutathione, was reacted with stoichiometric amounts of insulin and the sulfhydryl groups of the partially reduced hormone were labeled with iodo (l-C)acetamide. After separation of the insulin chains, the radioactivity was found in both the peptides, with a ratio A-chain/B-chain equal to 2/1. [ABSTRACT FROM AUTHOR]

Thermal and photochemical free radical reaction products of C with polymethyl methacrylate (PMMA) and polystyrene (PS) in orthodichlorobenzene solution were detected by EPR (electron paramagnetic resonance). Thermal radicals (<100°C) of C/PMMA and C/PS samples gave single line first-derivative EPR spectra with g=2.0029. Ultraviolet photolysis of a C/PMMA solid phase sample gave two radical species; whereas, photolysis of a C solid phase sample gave only one free radical. EPR signals were also recorded for UV and thermal C reaction with free radical initiator, azobis(isobutyronitrile). [ABSTRACT FROM AUTHOR]

Electron nuclear double resonance (ENDOR) spectra of free radicals produced by ultraviolet (UV) photolysis of polycrystalline and single crystal dimethylnitramine (or N-methyl-N-nitromethanamine) [DMN; (CH)NNO were studied at ca. −30°C. Results suggest that multiple radical species are formed during UV photolysis of DMN, perdeutero-DMN-d, andN-labeled DMN. Proton ENDOR spectra are consistent with assignment of a cation radical (CH)NNO as the major DMN radical species. Proton hyperfine coupling anisotropy, which is observed from the ENDOR spectra, is attributed to inequivalence of the two DMN methyl groups. [ABSTRACT FROM AUTHOR]

Energy flow through continental shelf food webs was examined using a simulation model. The model structure expands the two traditional marine food chains of phytoplankton-zooplankton-pelagic fish and benthos-demersal fish into a complex web which includes detritus, dissolved organic matter (DOM), bacteria, protozoa, and mucus net feeders. Simulation of energy flux for different shelf systems using the expanded web revealed that heterotrophic microorganisms and their predators account for a significant component of the energy flux in the continental shelf ecosystem. Contrary to previous models, where all phytoplankton were considered to be grazed by zooplankton, our simulation results indicate that only slightly more than 50% of the annual net primary production is grazed. A substantial quantity of the phytoplankton production directly becomes detritus. Bacteria mineralize detritus and DOM produced by phytoplankton and other components of the food web, converting these to biomass with high efficiency. Consequently, the model predicts that planktonic bacterial production is equivalent to zooplankton production. Exclusion of the bacteria requires the assumption that all DOM is either exported from the system or consumed by another component of the food web. Neither of these assumptions can be supported by present knowledge of the dynamics of DOM in the sea. Model simulations were also employed to test the hypothesis that production exceeds consumption on continental shelves, resulting in exports of 50% of the annual primary production. Simulations of shelves with high rates of primary production resulted in a particulate export of 27% and realistic estimates of secondary production. Results of other simulations suggest that shelves with lower primary production cannot export production and still maintain the macrobenthos and their predators. General properties about continental shelves can also be inferred from the model. From simulations of shelves of differing primary production, nanoplankton are predicted to account for a greater proportion of the primary production in nutrient limited systems. Benthic production appears to be related to both the quantity of primary production and the sinking rates of the phytoplankton. The model indicates that zooplankton fecal inputs to the shelf benthos are only a small portion of the total detrital flux, leading to the prediction that fecal pellets are of little significance in determining benthic production. Finally, the model generates production efficiencies that are highly variable depending on the type of system and kind of populations involved. We argue that the assumed ecological efficiency of 10% should be abandoned for continental shelves and other ecosystems. [ABSTRACT FROM AUTHOR]

We examined the potential limitation of bacterial growth by temperature and nutrients in a eutrophic lake. Dilution cultures from winter and summer were incubated at both high (>20°C) and low (4°C) temperatures and enriched with various combinations of organic carbon (C), inorganic nitrogen (N), and inorganic phosphorus (P). Bacterial abundance, H-thymidine incorporation, and H-leucine incorporation were measured over the growth cycle. For both winter and summer assemblages, low temperature limited growth even when resources (C, N, and P) were added. When temperature was adequate, bacterial growth in dilution cultures was co-limited by C, N, and P Additions of either C, P, or N and P alone provide little or only modest stimulation of growth, suggesting that under in situ conditions both nutrients and organic carbon limit bacterial growth. Our results provide little evidence of seasonal adaptation to low temperatures for bacterial communities in temperate lakes. Instead, bacterial growth appears to be temperature limited during winter and resource limited during summer. We propose that, in general, bacterial growth rates are temperature dependent up to a threshold, but that the patterns of change across temperature gradients are resource dependent, such that temperature has little effect on growth in resource-rich environments but a strong effect in resource-poor environments. [ABSTRACT FROM AUTHOR]

The regulation of bacterial community biomass and productivity by resources and predators is a central concern in the study of microbial food webs. Resource or bottom-up regulation refers to the limitation of bacteria by carbon and nutrients derived from allocthonous inputs, primary production, and heterotrophic production. Predatory or top-down regulation refers to the limitation of bacteria below levels supportable by resources alone. Large scale comparative studies demonstrate strong correlations between bacterial productivity and biomass, suggesting significant resource regulation. Comparisons of the abundances of heterotrophic flagellates and bacteria, however, imply that in some cases there may be top-down regulation of bacteria in eutrophic environments. Experimental studies in lakes support the importance of resource regulation and reveal little top-down control from protozoans. Increases in bacterial abundance and production with nutrient enrichment were limited in enclosure experiments with high abundances of the cladoceran, Daphnia. Regulation of bacteria by Daphnia may occur in many lakes seasonally and prevail in some lakes throughout the year where these animals sustain dense populations. In most situations, however, bacteria appear to be limited primarily by resources. [ABSTRACT FROM AUTHOR]