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A mechanistic understanding of factors that structure spatiotemporal community composition is a major challenge in microbial ecology. Our study of microbial communities in the headwaters of three freshwater stream networks showed significant community changes at the small spatial scale of benthic habitats when compared to changes at mid- and large-spatial scales associated with stream order and catchment. Catchment (which included temperate and tropical catchments) had the strongest influence on community composition followed by habitat type (epipsammon or epilithon) and stream orders. Alpha diversity of benthic microbiomes resulted from interactions between catchment, habitat, and canopy. Epilithon contained relatively more Cyanobacteria and algae while Acidobacteria and Actinobacteria proportions were higher in epipsammic habitats. Turnover from replacement created ~60%-95% of beta diversity differences among habitats, stream orders, and catchments. Turnover within a habitat type generally decreased downstream indicating longitudinal linkages in stream networks while between habitat turnover also shaped benthic microbial community assembly. Our study suggests that factors influencing microbial community composition shift in dominance across spatial scales, with habitat dominating locally and catchment dominating globally.

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PURPOSE: To identify preoperative factors that influence the outcomes of gastric bypass surgery, in terms of excess weight loss at 24 months. METHODS: This retrospective study included two groups of patients who underwent laparoscopic gastric bypass surgery. Group A (poor outcomes) had ≤ 50%EWL or BMI ≥ 30 kg/m2; group B (excellent outcomes) had ≥ 80%EWL at 24 months. A comparative analysis of demography, anthropometry, comorbidities, and metabolic status was performed. A linear regression model was used to evaluate %EWL association; the number of preoperative and postoperative consultations were also compared. RESULTS: A total of 202 patients completed follow-up; 71 (35.1%) and 78 (38%) had poor and excellent outcomes (%EWL 44.1 ± 9.4% vs. 92 ± 10.9%), respectively. Mean age was 40.4 ± 8.9 years. Patients with poor outcomes had higher weight and BMI, lesser preoperative %EWL, higher dyslipidemia and diabetes rates with longer periods of evolution, and increased HbA1c% levels. In the linear regression analysis, preoperative %EWL and initial and preoperative BMI were statistically significant determinants of %EWL at 24 months Diabetes remission was 46.2% (group A) vs. 66.6% (group B). Group A had higher non-attendance rates after surgery. CONCLUSION: The factors independently associated with greater %EWL at 24 months between groups were higher preoperative %EWL, and lower initial and preoperative BMI.

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Pressures from anthropogenic activities are causing degradation of estuarine and coastal ecosystems around the world. Trace metals are key pollutants that are released and can partition in a range of environmental compartments, to be ultimately accumulated in exposed biota. The level of pressure varies with locations and the range and intensity of anthropogenic activities. The present study measured residues of trace metals in Mytilus mussel species collected from a range of locations around the world in areas experiencing a gradient of anthropogenic pressures that we classified as low, moderate, or high impact. The data showed no grouping/impact level when sampling sites in all countries were incorporated in the analysis, but there was significant clustering/impact level for most countries. Overall, high-impact areas were characterized by elevated concentrations of zinc, lead, nickel, and arsenic, whereas copper and silver were detected at higher concentrations in medium-impact areas. Finally, whereas most metals were found at lower concentrations in areas classified as low impact, cadmium was typically elevated in these areas. The present study provides a unique snapshot of worldwide levels of coastal metal contamination through the use of Mytilus species, a well-established marine biomonitoring tool. Environ Toxicol Chem 2021;40:3434-3440. © 2021 SETAC.

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Bipolar disorder (BD) is a chronic mental illness characterized by changes in mood that alternate between mania and hypomania or between depression and mixed states, often associated with functional impairment. Although effective pharmacological and non-pharmacological treatments are available, several patients with BD remain symptomatic. The advance in the understanding of the neurobiology underlying BD could help in the identification of new therapeutic targets as well as biomarkers for early detection, prognosis, and response to treatment in BD. In this review, we discuss genetic, epigenetic, molecular, physiological and neuroimaging findings associated with the neurobiology of BD. Despite the advances in the pathophysiological knowledge of BD, the diagnosis and management of the disease are still essentially clinical. Given the complexity of the brain and the close relationship between environmental exposure and brain function, initiatives that incorporate genetic, epigenetic, molecular, physiological, clinical, environmental data, and brain imaging are necessary to produce information that can be translated into prevention and better outcomes for patients with BD.

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OBJECTIVES: To compare the health-related quality of life (HRQL) trajectories of a regional cohort of extremely low birth weight (ELBW, <1000 g) survivors (births from 1977 to 1982) and a group of normal birth weight (NBW) controls, at 3 ages: 12-16 years, 22-26 years, and 29-36 years, spanning over 20 years. We hypothesized that the HRQL of the ELBW cohort would be significantly compromised compared with their NBW peers, and that neurosensory impairments (NSI) would have an additional negative effect. STUDY DESIGN: We used the Health Utilities Index Mark 3, in which health status was self-assessed and utility scores were derived from community preferences; multilevel modeling was used to delineate trajectories of HRQL among ELBW survivors with (n = 37) and without NSI (n = 116), and NBW controls (n = 137). RESULTS: Adjusting for participant sex and socioeconomic status at age 8 years, ELBW survivors with NSI had consistently lower HRQL compared with both ELBW survivors without NSI and NBW controls, from adolescence through to adulthood (ß = -0.264; P < .001). ELBW survivors without NSI also had significantly lower HRQL compared with NBW controls (ß = -0.092; P < .01). At all ages, differences seen in the Health Utilities Index Mark 3 scores between ELBW participants and NBW controls were clinically important, though there was no differential rate of decline between the 2 groups. CONCLUSIONS: ELBW survivors manifest meaningfully poorer HRQL from their early teens through their mid-30s. Individuals with NSI appear to represent a distinct group of ELBW survivors with substantially lower HRQL at all ages. Information on HRQL can be helpful in prioritizing research and intervention strategies.

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OBJECTIVES: To estimate the risk of fatal and non-fatal myocardial infarction (MI) and stroke in patients with bipolar I disorder compared to people without bipolar I disorder. METHOD: Utilizing a records-linkage system spanning 30 years (1966-1996), a population-based cohort of 334 subjects with bipolar I disorder and 334 age and sex-matched referents from Olmsted County, Minnesota, U.S. was identified. Longitudinal follow-up continued until incident MI or stroke (confirmed by board-certified cardiologist/neurologist), death, or study end date (December 31, 2013). Cox proportional hazards models assessed the hazard ratio (HR) for MI or stroke, adjusting for potential confounders. RESULTS: There was an increased risk of fatal or non-fatal MI or stroke (as a composite outcome) in patients with bipolar I disorder [HR 1.54, 95% confidence interval (CI) 1.02, 2.33; p=0.04]. However, after adjusting for baseline cardiovascular risk factors (alcoholism, hypertension, diabetes, and smoking), the risk was no longer significantly increased (HR 1.19, 95% CI 0.76, 1.86; p=0.46). LIMITATIONS: Small sample size for the study design. Findings were not retained after adjustment for cardiovascular disease risk factors. Psychotropic medication use during the follow-up was not ascertained and was not included in the analyses. CONCLUSION: This study in a geographically defined region in the U.S. demonstrated a significant increased risk of MI or stroke in bipolar I disorder, which was no longer significant after adjustment for cardiovascular risk factors.

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Schizophrenia is a heterogeneous syndrome, varying between persons and over course of illness. In this and a companion article, we argue that comprehension of this condition or set of conditions may require combining a phenomenological perspective emphasizing disorders of basic-self experience ("ipseity disturbance") with a multidimensional appreciation of possible neurobiological correlates--both primary and secondary. Previous attempts to link phenomenology and neurobiology generally focus on a single neurocognitive factor. We consider diverse aspects of schizophrenia in light of a diverse, albeit interacting, set of neurocognitive abnormalities, examining both synchronic (structural) interdependence and diachronic (temporal) succession. In this article we focus on the primary or foundational role of early perceptual and motoric disturbances that affect perceptual organization and especially intermodal or multisensory perceptual integration ("perceptual dys-integration"). These disturbances are discussed in terms of their implications for three interconnected aspects of selfhood in schizophrenia, primary forms of: disrupted "hold" or "grip" on the world, hyperreflexivity, diminished self-presence (self-affection). Disturbances of organization or integration imply forms of perceptual incoherence or diminished cognitive coordination. The effect is to disrupt one's ability to apprehend the world in holistic, vital, or contextually grounded fashion, or to fully identify with or experience the unity of one's own body or thinking--thereby generating an early and profound (albeit often subtle) disruption or diminishment of basic or core self and of the sense of existing in a coherent world. We discuss interrelationships or possible complementarities between these three aspects, and consider their relevance for a neurodevelopmental account of schizophrenia.

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The objective of this study is to compare the removal of Taenia eggs to the removal of Ascaris eggs in a wastewater stabilization pond system consisting of three ponds in series, where the hydraulic residence time distribution has been characterized via a tracer study supported by computational fluid dynamics modeling. Despite a theoretical hydraulic retention time of 30 days, the peak dye concentration was measured in the effluent of the first pond after only 26 hours. The smaller-sized Taenia eggs were detected in higher concentrations than Ascaris eggs in the raw wastewater. Ascaris eggs were not detected in the pond system effluent, but 45 Taenia eggs/L were detected in the system effluent. If some of these eggs were of the species Taenia solium, and if the treated wastewater were used for the irrigation of crops for human consumption, farmers and consumers could potentially be at risk for neurocysticercosis. Thus, limits for Taenia eggs in irrigation water should be established, and precautions should be taken in regions where pig taeniasis is endemic. The results of this study indicate that the theoretical hydraulic retention time (volume/flow) of a pond is not always a good surrogate for helminth egg removal.

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Recent behavioral and electrocortical studies have found that shy and socially anxious adults are hypersensitive to the processing of negative and ambiguous facial emotions. We attempted to extend these findings by examining the neural correlates of affective face processing in shy adults using an event-related fMRI design. We presented pairs of faces that varied in affective valence and intensity. The faces were morphed to alter the degree of intensity of the emotional expressive faces. Twenty-four (12 shy and 12 non-shy) young adult participants then made same/different judgments to these faces while in an MR scanner. We found that shy adults exhibited greater neural activation across a distinct range of brain regions to pairs of faces expressing negative emotions, moderate levels of emotional intensity, and emotional faces that were incongruent with one another. In contrast, non-shy individuals exhibited greater neural activation across a distinct range of brain regions to pairs of faces expressing positive emotions, low levels of emotional intensity, and emotional faces that were congruent with one another. Findings suggest that there are differences in neural responses between shy and non-shy adults when viewing affective faces that vary in valence, intensity, and discrepancy.

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Recent behavioral and electrocortical studies have found that shy and socially anxious adults are hypersensitive to the processing of negative and ambiguous facial emotions. We attempted to extend these findings by examining the neural correlates of affective face processing in shy adults using an event-related fMRI design. We presented pairs of faces that varied in affective valence and intensity. The faces were morphed to alter the degree of intensity of the emotional expressive faces. Twenty-four (12 shy and 12 non-shy) young adult participants then made same/different judgments to these faces while in an MR scanner. We found that shy adults exhibited greater neural activation across a distinct range of brain regions to pairs of faces expressing negative emotions, moderate levels of emotional intensity, and emotional faces that were incongruent with one another. In contrast, non-shy individuals exhibited greater neural activation across a distinct range of brain regions to pairs of faces expressing positive emotions, low levels of emotional intensity, and emotional faces that were congruent with one another. Findings suggest that there are differences in neural responses between shy and non-shy adults when viewing affective faces that vary in valence, intensity, and discrepancy.(AU)

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A field study was conducted to determine the microbial community structures of streambed sediments across diverse geographic and climatic areas. Sediment samples were collected from three adjacent headwater forest streams within three biomes, eastern deciduous (Pennsylvania), southeastern coniferous (New Jersey), and tropical evergreen (Guanacaste, Costa Rica), to assess whether there is biome control of stream microbial community structure. Bacterial abundance, microbial biomass, and bacterial and microbial community structures were determined using classical, biochemical, and molecular methods. Microbial biomass, determined using phospholipid phosphate, was significantly greater in the southeastern coniferous biome, likely due to the smaller grain size, higher organic content, and lower levels of physical disturbance of these sediments. Microbial community structure was determined using phospholipid fatty acid (PLFA) profiles and bacterial community structure from terminal restriction fragment length polymorphism and edited (microeukaryotic PLFAs removed) PLFA profiles. Principal component analysis (PCA) was used to investigate patterns in total microbial community structure. The first principal component separated streams based on the importance of phototrophic microeukaryotes within the community, while the second separated southeastern coniferous streams from all others based on increased abundance of fungal PLFAs. PCA also indicated that within- and among-stream variations were small for tropical evergreen streams and large for southeastern coniferous streams. A similar analysis of bacterial community structure indicated that streams within biomes had similar community structures, while each biome possessed a unique streambed community, indicating strong within-biome control of stream bacterial community structure.

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Ouabain is an endogenous compound that has been associated with the genesis and maintenance of hypertension. This compound inhibits the Na+ pump activity, which leads to an accumulation of intracellular Na and ultimately might increase vascular tone. In nanomolar concentrations, it enhances vasopressor responses to phenylephrine in some vascular beds from normotensive and hypertensive rats. However, it is not known whether this action of ouabain is a common mechanism for all models of hypertension. The aim of this work was to determine whether ouabain can alter pressor responses to phenylephrine in rats with Nomega-nitro-l-arginine methyl ester (L-NAME)-induced hypertension. In anesthetized rats, ouabain (0.18 microg/kg, i.v.) increased arterial blood pressure in L-NAME-treated rats but not in controls. Ganglionic blockade by hexamethonium (5 mg/kg, i.v.) prevented the increase in arterial blood pressure produced by ouabain in L-NAME-treated rats. Additional studies using isolated perfused tail artery preparations were performed to investigate which factors are involved in the action of ouabain in L-NAME-treated rats. The effects of 10 nM ouabain on the vasoconstrictor actions of phenylephrine were determined on preparations with intact or damaged endothelium or in the presence of tetraethylammonium (a K+-channel blocker). Ouabain reduced pressor actions of phenylephrine in preparations with an intact endothelium. However, after endothelial damage or infusing tetraethylammonium, the response to phenylephrine was increased after ouabain. In tails from L-NAME-treated rats, the functional activity of the Na, K+-ATPase was reduced, and 10 nM ouabain did not produce any further reduction. In conclusion, in this model of hypertension, a low dose of ouabain (0.18 microg/kg) increased arterial blood pressure in vivo probably as a result of increased sympathetic tone. However, this effect was not accompanied by an enhanced action of phenylephrine on the tail vascular bed with an intact endothelium. The results suggest that this was due to the release of an endothelium-derived K+-channel opener.

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Se evaluaron 4500 historias de pacientes a los que se les realizó recto-sigmoidoscopia en la unidad de Endoscopia del Hospital de Clínicas Caracas como parte de una evaluación médica preventiva entre Julio de 1995 y Abril de 1997. Se examina la incidencia de algunas patologías colorectales, como la presencia de pólipos, divertículos, entre otras, así como su relación con la edad y el sexo de los pacientes. En este estudio se demuestra que la recto

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Given the relatively high standards of living in Barbados, indicated by the per capita income of U.S. $3.500, level of education and health care, and the activities of the National Nutrition Centre since 1972, it was felt that the prevalence of malnutrition (8.8 percent) reported in the 1981 National Health and Nutrition Survey was still relatively high. It was, therefore, decided to determine the prevalence of malnutrition in a clinic and factors associated with the nutritional status of the children. Weights and ages of all children 6-42 months of age on clinic records were noted. Then the parents or guardians of 104 children (52 malnourished or index and 52 normal or comparison) attending the clinic were interviewed. Anthropometric measurements (weight, height and head circumference) of the 104 children were taken; and information from both their clinic records and their mothers' maternity records was noted. In the index group (46 percent) mothers were employed compared with 40 (77 percent) in the comparison group, a difference that was statistically significant. There were 20 and 39 houses in the index group with piped water in the house and in poor state of disrepair respectively compared with 37 and 49 in the comparison group, differences that were significant at the 1 percent and 5 percent level respectively. The comparison group had significantly more households with gas stove (50), kitchen appliances (31), telephone (30) and refrigerators (42), than the index group: gas stove (41), kitchen appliances (18), telephone (19) amd refrigerator (31). In the study 22 children in the index group compared with all 52 children in the comparison group were receiving their first solid food too early and too late respectively; these differences were statistically significant. In the present diet, significantly larger numbers of children in the comparison group were receiving milk and cereal, 38 and 32 children respectively, than in the index group, 25 and 21 children. However, significantly more children (18) in the index group were receiving bush teas than the comparison group, 2 children. In the index group 21, children had low birth weights (i.e. 2500g) compared with 1 child in the comparison group. Similarly, more children (34) in the index group than the comparison group (21) were ill; and 23.1 percent of the index sick children had 3 or more episodes compared with 3.8 percent in the comparison group. All these differences were significant at p<0.001. In addition to those factors already mentioned, there are a number of other factors thought to be associated with poor nutritional status but which were not found to be so in this study. For example, there was no difference in the level of educational attainment of mothers in the index group (19 primary, 33 post-primary) and the comparison group (19 primary, 33 post-primary). Further, both groups had a similar family size: index 6.7 and comparison 6.3. Other factors not associated were presence of male head (50.0 percent index, 63.5 percent comparison); working male head and mothers' age and union status. Yet it should be noted that there was a tendency for the comparison group to have higher values than the index group. It was concluded that: (1) the socioeconomic or standard of living conditions in the comparison group were better than those of the index groups indicated by mother's employment, mean household income, crowding, better housing and household amenities such as gas stove, refrigerator and telephone. (2) Feeding practices in the comparison group were generally better than in the index group as indicated by dilution of milk formula, age first solid foods were given and receiving cereals and milk in their diet (3) children who are sick and have frequent episodes of illnesses are more likely to have low nutritional status; and (4) children with normal birth weights are more likely to have better nutrition status (AU)

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