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Wary of the 'denial of coevalness' associated with earlier anthropology, anthropologists at the turn of the millennium increasingly emphasized how sharing not just space but also time is constitutive of the ethnographic encounter. However, drawing on online and offline fieldwork conducted in Jordan, I use the tensions between a blood feud and the holy month of Ramadan to illustrate how humans often refuse to inhabit each others' histories and temporal schemes regardless of the presence of anthropologists. I argue that discomfort with acknowledging such refusals of coevalness has increasingly hobbled anthropological description, especially at a time when new communications technologies are re-shaping human experiences of sharing (and not sharing) space and time. I suggest that anthropologists would benefit from following many of the Jordanian Muslims I encountered in attending to how one does not 'share time' with various others – as well as the ways in which one does. [ABSTRACT FROM AUTHOR]

A simple analytical approach has been developed to determine the series resistance, Rs, of a solar cell. The method adopted here depends only on the knowledge of the open-circuit voltage, Voc, and the current and voltage at the maximum power point, Isc and Vmp respectively. This approach, based on a knowledge of these operating output parameters of the cell, provides a theoretical framework for an existing computer simulated approach which has been widely used in industries. [ABSTRACT FROM AUTHOR]

Cyclosporin is an immunosuppressive agent in allogeneic hematopoietic stem cell transplantation and its metabolism is strongly affected by concomitant drugs, including posaconazole which is now extensively used as anti-fungal prophylaxis post-allograft. We undertook a retrospective audit of 29 patients undergoing their first allograft who were receiving posaconazole at the time of transition from intravenous to oral cyclosporin. This group had a median initial oral cyclosporin dose of 2.58 mg/kg bd (range 1.75–3.95) and high incidence of cyclosporin-related toxicity was noted, requiring significant dose reductions such that by day 60 the media dose was 1.60 mg/kg bd (range 0.86–3.33). We subsequently amended our dosing protocol and analyzed a further 20 patients specifying an initial oral cyclosporin dose of 2.25 mg/kg bd and found this had little impact on toxicity or requirement for dose reductions. Starting doses of no greater than 2 mg/kg bd appear optimal to prevent toxicity in allograft recipients receiving concomitant posaconazole. [ABSTRACT FROM AUTHOR]

Human oral exposure to copper oxide nanoparticles (NPs) may occur following ingestion, hand-to-mouth activity, or mucociliary transport following inhalation. This study assessed the cytotoxicity of Cupric (II) oxide (CuO) and Cu2O-polyvinylpyrrolidone (PVP) coated NPs and copper ions in rat (intestine epithelial cells; IEC-6) and human intestinal cells, two- and three-dimensional models, respectively. The effect of pretreatment of CuO NPs with simulated gastrointestinal (GI) fluids on IEC-6 cell cytotoxicity was also investigated. Both dose- and time-dependent decreases in viability of rat and human cells with CuO and Cu2O-PVP NPs and Cu2+ ions was observed. In the rat cells, CuO NPs had greater cytotoxicity. The rat cells were also more sensitive to CuO NPs than the human cells. Concentrations of H2O2 and glutathione increased and decreased, respectively, in IEC-6 cells after a 4-h exposure to CuO NPs, suggesting the formation of reactive oxygen species (ROS). These ROS may have damaged the mitochondrial membrane of the IEC-6 cells causing a depolarization, as a dose-related loss of a fluorescent mitochondrial marker was observed following a 4-h exposure to CuO NPs. Dissolution studies showed that Cu2O-PVP NPs formed soluble Cu whereas CuO NPs essentially remained intact. For GI fluid-treated CuO NPs, there was a slight increase in cytotoxicity at low doses relative to non-treated NPs. In summary, copper oxide NPs were cytotoxic to rat and human intestinal cells in a dose- and time-dependent manner. The data suggests Cu2O-PVP NPs are toxic due to their dissolution to Cu ions, whereas CuO NPs have inherent cytotoxicity, without dissolving to form Cu ions. [ABSTRACT FROM AUTHOR]

We ascertained various life-history traits from an examination of 310 museum specimens of the Rio Grande leopard frog (Lithobates berlandieri) collected during 1907-2016 from Texas, USA. Lithobates berlandieri was captured during every month of the year except November, and adults were most frequently encountered during January-September, with a distinct peak in May. Mean body size of adult males (69.5 mm) was smaller than that of adult females (77.5 mm), and adult body sizes tended to be smaller at higher latitudes, a trend that was more pronounced in males. Females were gravid during January-September, and most gravid females were captured from late winter to early summer. Gonadal enlargement in males was generally high throughout January-September with no detectable seasonal increase. Feeding became widespread in both sexes during May-June shortly after a spring breeding bout. Spent females (ovarian stage 1) were common in July and lipid deposition increased in June/July, signalling oogenesis for breeding in the fall. From 15 gravid females, we estimated a mean clutch size of 3107 eggs which was correlated with female body size, yet egg diameter was not related to clutch or body size. Age to metamorphosis was likely 2-4 months depending upon whether eggs were laid in the winter/spring or late fall. If metamorphosis occurred in May/June, the minimum size at sexual maturity could have been reached in 7-8 months for adult males (50.1 mm) and in 9-10 months for adult females (57.2 mm). Mean adult body sizes, however, may have taken 14 to 17 months to reach. A synthesis across Texas populations suggests that the breeding season extends almost continuously from the fall through the winter and spring until mid-summer and is interrupted by extreme temperatures in the winter and summer. [ABSTRACT FROM AUTHOR]

1. It was important to investigate the disposition of decabromodiphenyl ethane (DBDPE) based on concerns over its structural similarities to decabromodiphenyl ether (decaBDE), high potential for environmental persistence and bioaccumulation, and high production volume. 2. In the present study, female Sprague Dawley rats were administered a single dose of [14C]-DBDPE by oral, topical or IV routes. Another set of rats were administered 10 daily oral doses of [14C]-DBDPE. Male B6C3F1/Tac mice were administered a single oral dose. 3. DBDPE was poorly absorbed following oral dosing, with 95% of administered [14C]-radioactivity recovered in the feces unchanged, 1% recovered in the urine and less than 3% in the tissues at 72 h. DBDPE excretion was similar in male mice and female rats. Accumulation of [14C]-DBDPE was observed in liver and the adrenal gland after 10 daily oral doses to rats. 4. Rat and human skin were used to assess potential dermal uptake of DBDPE. The dermis was a depot for dermally applied DBDPE; conservative estimates predict ∼14 ± 8% of DBDPE may be absorbed into human skinin vivo; ∼7 ± 4% of the parent chemical is expected to reach systemic circulation following continuous exposure (24 h). 5. Following intravenous administration, ∼70% of the dose remained in tissues after 72 h, with the highest concentrations found in lung (1223 ± 723 pmol-eq/g), spleen (1096 ± 369 pmol-eq/g) and liver (366 ± 98 pmol-eq/g); 5 ± 1% of the dose was recovered in urine and 26 ± 4% in the feces. [ABSTRACT FROM AUTHOR]

Engineered nanomaterials (ENM) are a growing aspect of the global economy, and their safe and sustainable development, use, and eventual disposal requires the capability to forecast and avoid potential problems. This review provides a framework to evaluate the health and safety implications of ENM releases into the environment, including purposeful releases such as for antimicrobial sprays or nano-enabled pesticides, and inadvertent releases as a consequence of other intended applications. Considerations encompass product life cycles, environmental media, exposed populations, and possible adverse outcomes. This framework is presented as a series of compartmental flow diagrams that serve as a basis to help derive future quantitative predictive models, guide research, and support development of tools for making risk-based decisions. After use, ENM are not expected to remain in their original form due to reactivity and/or propensity for hetero-agglomeration in environmental media. Therefore, emphasis is placed on characterizing ENM as they occur in environmental or biological matrices. In addition, predicting the activity of ENM in the environment is difficult due to the multiple dynamic interactions between the physical/chemical aspects of ENM and similarly complex environmental conditions. Others have proposed the use of simple predictive functional assays as an intermediate step to address the challenge of using physical/chemical properties to predict environmental fate and behavior of ENM. The nodes and interactions of the framework presented here reflect phase transitions that could be targets for development of such assays to estimate kinetic reaction rates and simplify model predictions. Application, refinement, and demonstration of this framework, along with an associated knowledgebase that includes targeted functional assay data, will allow betterde novopredictions of potential exposures and adverse outcomes. [ABSTRACT FROM AUTHOR]

Metal nanoparticles can potentially contact human skin during their manufacture and use in commercial products. This study examined the potential of metal nanoparticles to elicit irritant contact dermatitis in a human skin equivalent model (HSEM) derived from keratinocytes. Ag (10–100 nm), TiO2(22–214 nm), and CeO2(15–40 nm) nanoparticles were studied. The Ag particles were either coated/shelled with silica or capped with citrate or polyvinylpyrrolidone and were in water. The TiO2and CeO2particles were suspended in media containing 10% fetal bovine serum. The particles (1 mg/ml) were applied to the epidermal surface of the HSEM. Positive (5% sodium dodecyl sulfate (SDS)) and negative controls (saline or media) were included. After 1-h exposure at 37 °C, the HSEM was washed with saline to remove the nanoparticles. Following a 42-h incubation (37 °C), HSEM viability was assessed using the MTT assay. A test substance is considered a dermal irritant if the HSEM viability is < 50%. The mean viability for the SDS-treated HSEM was 7.8%. The viabilities of the nanoparticle-treated HSEM were 91% or greater. The Ag, TiO2, and CeO2nanoparticles examined were not dermal irritants under the conditions used in this study. The stratum corneum of the HSEM may limit penetration of metal nanoparticles to induce toxicity. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate how the type of contact influences physiological, perceptual and locomotive load during a simulated rugby league match. Eleven male university rugby league players performed two trials of the rugby league movement simulation protocol for interchange forwards with a traditional soft tackle bag and a weighted tackle sled to replicate contact demands. The interchange forward-specific simulation was chosen given the contact frequency is higher for this group of players compared to whole match players. Locomotive rate, sprint speed, tackle intensity, heart rate (HR) and rating of perceived exertion were analysed during the first and second bouts that replicated two ~23 min on-field passages. Countermovement jump (CMJ) was measured before and immediately after each trial. More time was spent in heart rate zone between 91 and 100% HRpeakduring the first (effect size ± 90% confidence interval: 0.44 ± 0.49) and second bouts (0.44 ± 0.43), and larger (0.6 ± 0.69) decrements in CMJ performance were observed during the sled trial (5.9,s = 4.9%) compared to the bag trial (2.6,s = 5.4%). Changing the type of contact during the match simulation subtly altered both the internal and external loads on participants. Using a standard tackle bag results in faster sprint speed to contact, but lower overall high-intensity running. Conversely, a heavier tackle object increases the internal load and results in greater lower limb neuromuscular fatigue as reflected by the decrease in CMJ performance. [ABSTRACT FROM PUBLISHER]

1. Pyrethroids are neurotoxic and parent pyrethroid appears to be toxic entity. This study evaluated the oral disposition and bioavailability of bifenthrin in the adult male Long-Evans rat. 2. In the disposition study, rats were administered bifenthrin (0.3 or 3 mg/kg) by oral gavage and serially sacrificed (0.25 h to 21 days). Blood, liver, brain and adipose tissue were removed. In the bioavailability study, blood was collected serially from jugular vein cannulated rats (0.25 to 24 h) following oral (0.3 or 3 mg/kg) or intravenous (0.3 mg/kg) administration of bifenthrin. Tissues were extracted and analyzed for bifenthrin by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). 3. Bifenthrin concentration in blood and liver peaked 1–2-h postoral administration and were approximately 90 ng/ml (or g) and 1000 ng/ml (or g) for both tissues at 0.3 and 3 mg/kg, respectively. Bifenthrin was rapidly cleared from both blood and liver. Brain concentrations peaked at 4–6 h and were lower than in blood at both doses (12 and 143 ng/g). Bifenthrin in adipose tissue peaked at the collected time points of 8 (157 ng/g) and 24 (1145 ng/g) h for the 0.3 and 3 mg/kg doses, respectively and was retained 21 days postoral administration. Following intravenous administration, the blood bifenthrin concentration decreased bi-exponentially, with a distribution half-life of 0.2 h and an elimination half-life of 8 h. Bifenthrin bioavailability was approximately 30%. These disposition and kinetic bifenthrin data may decrease uncertainties in the risk assessment for this pyrethroid insecticide. [ABSTRACT FROM PUBLISHER]

Exposure to pyrethroid pesticides is a potential cause for concern. The objective of this study was to examine the in vivo dermal absorption of bifenthrin, deltamethrin, and permethrin in the rat. Dorsal hair on adult male Long-Evans rats was removed. The next day, the skin was dosed with 1750 nmol (312.5 nmol/cm2) of radiolabeled (5 µCi) bifenthrin, deltamethrin, or permethrin in acetone. A nonoccluding plastic cover was glued over the dosing site. The animals were placed in metabolism cages to collect excreta. At 24 h postdosing, the skin was washed with soap and water, and rats in one group were euthanized and their tissues were collected. The skin was removed and tape stripped. The remaining animals were returned to the metabolism cages after the wash for 4 d. These rats were then euthanized and handled as already described. Excreta, wash, tape strips, tissues, and carcass were analyzed for pyrethroid-derived radioactivity. The wash and tape strips removed >50% of the dose and skin retained 9–24%. Cumulative radioactivity in excreta was 0.5–7% at 24 h and 3–26% at 120 h. Radioactivity in tissues was <0.3% of the dose, while carcass retained 2 to 5%. Assuming absorption equals cumulative recovery in skin (washed and tape stripped), excreta, tissues, and carcass, absorption was permethrin ~ bifenthrin > deltamethrin at 24 h and permethrin > deltamethrin > bifenthrin at 120 h. Using the parallelogram approach with published in vitro data, human dermal absorption of these pyrethroids was estimated to be <10% of the dose. [ABSTRACT FROM AUTHOR]

Grades historically have indicated student performance in college. Previous studies in the higher education literature, primarily conducted at four-year teaching institutions, have suggested reasons for grade inflation but have provided little supporting empirical data. This quantitative, non-experimental, comparative study used survey research to explore whether there is a difference in the degree to which full-time and adjunct faculties perceived themselves to be influenced by factors thought to be associated with grade inflation, specifically in a community college setting. Data analyzed from 1,559 full-time and adjunct faculty of a Midwestern community college in the United States indicated full-time faculty felt they were significantly more influenced by administration pressures than adjunct faculty in their grade assignment, whereas adjunct faculty reported being most often influenced by student concerns such as (a) personal circumstances, (b) academic anxieties, and (c) success after the course. [ABSTRACT FROM AUTHOR]

This qualitative study examines older adults’ subjective views on the types and purposes of social activities. In-depth interviews were conducted with a purposive sample of 20 older adults, with low (n= 10) and high (n= 10) memory performance. We used grounded theory methods to analyze the narrative data. Four types of social activities—altruism, creativity, game, and motion—were identified. The purpose of social activities included enjoyment, relaxation, stimulation, and belongingness. Those in the low memory group seemed to face more barriers to participation. Different types of social activities may be important for cognitive health and well-being. [ABSTRACT FROM PUBLISHER]

Exposure to contaminated soil and dust is an important pathway in human health risk assessment. Physical and chemical characteristics and biological factors determine the bioaccessibility/bioavailability of soil and dust contaminants. Within a single sample, contamination may arise from multiple sources of toxic elements that may exist as different species that impact bioavailability. In turn, the bioaccessibility/bioavailability of soil and dust contaminants directly impacts human health risk. Research efforts focusing on development and application ofin vitroandin vivomethods to measure the bioaccessibility/bioavailability of metal-contaminated soils have advanced in recent years. The objective of this workshop was to focus on developments in assessing the bioaccessibility/bioavailability of arsenic-contaminated soils, metals’ contamination in urban Canadian residences and potential children's exposures to toxic elements in house dust, an urban community-based study (i.e., West Oakland Residential Lead Assessment), bioavailability studies of soil cadmium, chromium, nickel, and mercury and human exposures to contaminated Brownfield soils. These presentations covered issues related to human health and bioavailability along with the most recent studies on community participation in assessing metals’ contamination, studies of exposures to residential contamination, andin vitroandin vivomethods development for assessing the bioaccessibility/bioavailability of metals in soils and dusts. [ABSTRACT FROM AUTHOR]

In most countries, the dietary folate intake associated with adequate status of red cell folate and/or serum folate provides the basis for formulating reference values. One of the major challenges in setting dietary reference values for folate, however, is the need to account for the differences in bioavailability between the natural forms of the vitamin and the synthetic form, folic acid, albeit to date, few countries in Europe take bioavailability into consideration. A series of systematic reviews that included only those studies which used the most robust measures of both folate intake and folate status were carried out by the EURRECA Network of Excellence to examine the relationships between folate intake, status, and a number of health outcomes relevant to specific stages of the lifecycle. This review summarizes the available evidence and the issues to consider in the setting of dietary reference values for folate. [ABSTRACT FROM AUTHOR]

Zerovalent iron nanoparticles (nZVI) are used for in situ remediation of contaminated ground water, raising the possibility that nZVI particles or their altered residues could contaminate the ground water. Therefore, it is important to study their effects on humans and other organisms in vivo. The objective of this study was to assess the whole-body retention and terminal disposition of neutron-activated radioactive nZVI administered by oral gavage in mice. Radioactivity was primarily eliminated in the faeces within 1 day of administration. However, a small amount of iron-derived radioactivity appeared in the liver after three repeated daily doses. This prototypic study further suggests that neutron activation applied judiciously may be broadly applicable to studies of nanoparticles derived from other biologically abundant metals. [ABSTRACT FROM AUTHOR]

A mouse assay for measuring the relative bioavailability (RBA) of arsenic (As) in soil was developed. In this study, results are presented of RBA assays of 16 soils, including multiple assays of the same soils, which provide a quantitative assessment of reproducibility of mouse assay results, as well as a comparison of results from the mouse assay with results from a swine and monkey assay applied to the same test soils. The mouse assay is highly reproducible; three repeated assays on the same soils yielded RBA estimates that ranged from 1 to 3% of the group mean. The mouse, monkey, and swine models yielded similar results for some, but not all, test materials. RBA estimates for identical soils (nine test soils and three standard reference materials [SRM]) assayed in mice and swine were significantly correlated (r = 0.70). Swine RBA estimates for 6 of the 12 test materials were higher than those from the mouse assay. RBA estimates for three standard reference materials (SRM) were not statistically different (mouse/swine ratio ranged from 0.86–1). When four test soils from the same orchard were assessed in the mouse, monkey, and swine assays, the mean soil As RBA were not statistically different. Mouse and swine models predicted similar steady state urinary excretion fractions (UEF) for As of 62 and 74%, respectively, during repeated ingestion doses of sodium arsenate, the water-soluble As form used as the reference in the calculation of RBA. In the mouse assay, the UEF for water soluble AsV(sodium arsenate) and AsIII(sodium [meta] arsenite) were 62% and 66%, respectively, suggesting similar absolute bioavailabilities for the two As species. The mouse assay can serve as a highly cost-effective alternative or supplement to monkey and swine assays for improving As risk assessments by providing site-specific assessments of RBA of As in soils. [ABSTRACT FROM PUBLISHER]

A framework of 'Common Criteria' (i.e. a series of questions) has been developed to inform the use and evaluation of biomonitoring data in the context of human exposure and risk assessment. The data-rich chemical benzene was selected for use in a case study to assess whether refinement of the Common Criteria framework was necessary, and to gain additional perspective on approaches for integrating biomonitoring data into a risk-based context. The available data for benzene satisfied most of the Common Criteria and allowed for a risk-based evaluation of the benzene biomonitoring data. In general, biomarker (blood benzene, urinary benzene and urinary S-phenylmercapturic acid) central tendency (i.e. mean, median and geometric mean) concentrations for non-smokers are at or below the predicted blood or urine concentrations that would correspond to exposure at the US Environmental Protection Agency reference concentration (30 µg/m3), but greater than blood or urine concentrations relating to the air concentration at the 1 × 10−5 excess cancer risk (2.9 µg/m3). Smokers clearly have higher levels of benzene exposure, and biomarker levels of benzene for non-smokers are generally consistent with ambient air monitoring results. While some biomarkers of benzene are specific indicators of exposure, the interpretation of benzene biomonitoring levels in a health-risk context are complicated by issues associated with short half-lives and gaps in knowledge regarding the relationship between the biomarkers and subsequent toxic effects. [ABSTRACT FROM AUTHOR]

The article cites a study, conducted by the authors, which studied the clinical characteristics and management options of patients with serum immunoglobulin A endomysial antibodies and intact duodenal villi. The diagnosis of coeliac disease has traditionally required the demonstration of villous atrophy (VA) in biopsies taken from the proximal small bowel, followed by response, usually assessed clinically, to a gluten-free diet. In the study, over an 8-year period, a total of 35 patients had positive endomysial serology yet had no VA on any of three biopsies taken from the second part of duodenum during a subsequent endoscopy.

Many fungi require a dimorphic switch from budding to filamentous growth to cause infection. Although the control of dimorphism has been elucidated for organisms such as Saccharomyces cerevisiae and Ustilago maydis, almost nothing is known about the control of mating and dimorphism in Microbotryum violaceum. M. violaceum mepA, mepC and smtE are homologs of genes whose encoded products act as, or interact with, components of the MAPK and cAMP-PKA pathways, conserved pathways that regulate mating and dimorphism in other fungi. A comparison of gene expression under various in vitro conditions was superimposed on a comparison of in vitro vs. in planta expression to yield a more complete picture of the expression of these genes in M. violaceum during fungal development. For the most part the expression of these genes was highest on low ammonium, intermediate for mated and in planta, and lowest on rich medium. As expected, under conditions of low ammonium, expression of the M. violaceum ammonium permease genes mepA and mepC mirrors that of S. cerevisiae MEP2 and U. maydis ump2. An intriguing possibility is that MepA is a sensor to signal when conditions are conducive for mating. The upregulation of smtE, which encodes a PAK kinase, suggests that the MAPK pathway regulates, at least partially, mating and might be linked to ammonium sensing/transport in M. violaceum. [ABSTRACT FROM AUTHOR]

Background: Serum antibodies to tissue transglutaminase (tTGA) are reported to have high sensitivity and specificity for coeliac disease and to correlate closely with endomysial antibodies (EmA). We assessed their performance in a coeliac population with a high proportion of EmA-negative patients, who have been under-represented in previous studies. Methods: We used a commercial ELISA kit to test for IgA class tTGA in sera from a population of 73 untreated coeliac patients with normal serum IgA and a high percentage (19%) EmA-negative, taking 58 patients with normal duodenal biopsies as controls. EmA was measured using indirect immunofluorescence. Results: Forty-six (63%) patients with villous atrophy (VA) had both tTGA and EmA. However, when considered separately, sensitivities of tTGA and EmA for VA were similar (75% versus 81%) and both had high specificity (98% versus 97%). As 9 patients were tTGA-positive only and 13 had EmA only, selection of patients for biopsy on the presence of either antibody would have had a sensitivity of 93% (68 of 73), with 5 (7%) patients seronegative for both. Conclusion: Although the ELISA tTGA assay is more convenient than EmA testing, it offers no advantages in sensitivity or specificity if used in isolation. However, incomplete concordance between EmA and tTGA positivity means that combination screening with both assays offers higher sensitivity, as almost a third of patients have only one antibody. As some coeliac patients with normal serum IgA are negative for both antibodies, biopsies should still be performed in seronegative individuals deemed at high risk for coeliac disease. [ABSTRACT FROM AUTHOR]

Exposure to the drinking water contaminant arsenate is a daily occurrence and there are concerns that this exposure may lead to cancer. Although the acute dispositional effects of arsenate have been studied in detail, there is minimal information on the disposition and toxicological effects of it after continuous exposure. The objective of this study was to examine in mice the effect of a 4-wk treatment with arsenate administered in drinking water. Female B6C3F1 mice (3/cage) were housed in metabolism cages and given water and food ad libitum. Two groups (A, B) of mice were treated (4 cages/treatment/group) with distilled water (control, C) or water containing 0.025 mg/L (L) or 2.5 mg/L (H) arsenate. Group A was sacrificed on d 28 and plasma and urine samples were taken for determination of clinical chemistry parameters. Liver and kidney tissue samples were taken for histopathological analysis. The reduced nonprotein sulfhydryl (NPSH) content in several tissues was determined. Group B was gavaged with [ 73As]arsenate on d 28 and continued the arsenate drinking water exposure for 48 h. Excreta and tissues were collected and analyzed for 73As. Urine was further analyzed for arsenate and its metabolites. There were no effects on the mean daily amount of water and food consumed, whereas the mean daily urine volume excreted was significantly elevated by 10% in the H-treated animals compared to C and L. A dose-related hepatic vacuolar degeneration in the liver was observed, but no histological changes were evident in the kidney. Only clinical chemistry parameters in plasma were altered by the arsenate treatment. Glucose was significantly lower at the H dose compared to C and L, triglycerides were significantly greater in C than L and H, and creatinine was significantly greater in H than C. Hepatic NPSH content in the H animals was significantly lower than C and L animals, whereas no effects in lung and kidney were detected. The weights of liver, lung, and kidney, as well as their tissue/body weight ratios, were significantly decreased in the H animals. 73As was primarily eliminated in urine, and its elimination was not affected by dose. No effects on the 48-h 73As cumulative excretion (urine + fecal) were detected. The 73As distribution was low in amount and widely dispersed throughout the animal (<3% of the 73As dose). The kidney had the highest 73As concentration of the tissues (0.01% 73As dose/g tissue). Dimethylarsinic acid was the major metabolite detected in urine, with lower amounts of arsenate, arsenite, and monomethylarsonate. There were no differences between the treatment groups in the amount of urinary metabolites after a single dose of [ 73As]arsenate. Several toxicological effects were observed in animals administered arsenate in drinking water, but no changes in the disposition of this arsenical were detected at the doses used in this study. [ABSTRACT FROM AUTHOR]

The organic arsenicals monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA) are the primary metabolites of inorganic arsenic, a known human carcinogen. The objective of this study was to examine if dose would affect the excretion and terminal tissue disposition of MMA and DMA in the mouse. 14C-MMA (4.84 and 484 mumol/ kg) and-DMA ( 8.04 and 804 mumol/kg) were administered to female micevia the tail vein. The mice were placed in metabolism cages for collection of urine (1, 2, 4, 8, 12, and 24 h) and feces ( 24 h) . The animals were then sacrificed at 24 h and tissues were removed and analyzed for radioactivity. The urine was also analyzed for parent compound and metabolites. Urinary excretion of MMA- and DMA-derived radioactivity predominated over fecal excretion. Dose did not affect the overall urinary excretion of both compounds. However, fecal excretion was significantly lower in the low-dose MMA-treated animals as opposed to in the high-dose group, whereas in the high-dose DMA-treated group excretion was lower than in the low-dose DMA group. The retention of radioactivity was low ( <2% of dose) and the distribution pattern similar for both compounds, with carcass > liver >kidney > lung. The concentration of radioactivity (% dose/ g tissue) was greater in kidney than in liver, lung, and blood for both compounds. The distribution and concentration of MMA-derived radioactivity was significantly greater in the liver and lung of the high-dose group. The MMA-treated animals excreted predominantly MMA in urine and lower amounts of DMA (<10% of the dose). The percentage excreted as DMA was significantly higher in the low-dose MM A group. In the urine of DMA-treated anim als, an unstable metabolite and the parent compound were detected. Overall, it appears the dose of organic arsenical administered has a minimal effect on its excretion and terminal tissue disposition in the mouse. The rapid elimination and low retention of MMA and DMA explain in part their low acute toxicity. [ABSTRACT FROM AUTHOR]

To determine the association of Type A behavior and coronary heart disease risk factors in children with a familial predisposition for premature atherosclerosis, subjects 6 to 16 years of age were evaluated on psychological and coronary risk measures. Subjects were classified as being Type A or Type B using the Student Structured Interview. Type A subjects had lower total serum and LDL cholesterol levels and lower systolic and diastolic blood pressure than Type B subjects. In addition, Type A subjects had more social competence skills and less behavioral disturbance relative to Type B subjects. Type A subjects tended to have better endurance on treadmill stress testing. These results suggest that in children with increased risk for coronary artery disease, the Type A behavior pattern may be associated with better fitness, better psychological health, and lower serum cholesterol levels. We hypothesized that the psychological and physiological characteristics of children with Type A behavior may enable them to adopt hygienic lifestyles more readily than children with Type B behavior. [ABSTRACT FROM AUTHOR]

Background: The histological lesion of gluten sensitivity primarily affects the proximal small bowel. The purpose of this study was to assess whether there were features of gluten-sensitive enteropathy in biopsies taken from the terminal ileum during colonoscopy/ileoscopy. Specific and sensitive abnormalities might facilitate diagnosis of coeliac disease in patients undergoing colonoscopy as their initial procedure or help select those who should proceed to upper gastrointestinal endoscopy and duodenal biopsy. Methods: Terminal ileal biopsies, taken from 30 patients with duodenal villous atrophy consistent with coeliac disease and from 60 control patients with no evidence of coeliac or inflammatory bowel disease, were reviewed blindly and compared. Biopsies were assessed for the presence or absence of villous atrophy and crypt hyperplasia, and counts were made of intraepithelial lymphocytes (IELs). Results: One patient only, in the coeliac group, had partial villous atrophy with crypt hyperplasia in the terminal ileum. IEL counts were significantly higher ( P < 0.005) in the coeliac group than among controls (mean per 100 enterocytes 26 versus 10). An ileal IEL count ≥25 had a sensitivity for duodenal villous atrophy (VA) of 60% and specificity of 100%. Conclusions: Coeliac disease may affect the entire small bowel. Increased IEL density in the terminal ileum is associated with duodenal VA and should prompt a search for coeliac disease by serology and duodenal biopsy. Conversely, a normal IEL count does not allow the exclusion of coeliac disease with confidence. [ABSTRACT FROM AUTHOR]

Background: Although IgA endomysial antibody (EmA) is currently the serologic test of choice in selecting suspected coeliac patients for duodenal biopsies, false-negative cases have been reported and may be more common than previous studies suggest. We assessed the sensitivity of EmA for patients with biopsy-confirmed villous atrophy (VA). Methods: We studied 89 patients without IgA deficiency for whom biopsy had not been primarily prompted by a positive EmA result. VA was graded as partial, subtotal, or total (PVA, STVA, TVA). Serum EmA was assayed with indirect immunofluorescence. Results: The sensitivity of EmA for VA was 78% (69 of 89) and was similar for PVA (79%) and ST/TVA (77%). Only 4 of the 20 EmA-negative patients had increased serum IgA-class antigliadin antibody levels as measured with enzyme-linked immunosorbent assay. All seronegative patients who complied with dietary gluten exclusion responded clinically, with histologic improvement after 12 months in 8 (67%) of 12 patients who had follow-up biopsies. Conclusions: EmA-negative coeliac disease is common. Reliance on EmA testing to select patients for biopsy will result in significant underdiagnosis. [ABSTRACT FROM AUTHOR]

Background: Coeliac disease is common yet often undiagnosed because symptoms may be trivial, non-specific, or non-gastrointestinal, or because of lack of clinician awareness. Serum IgA-class endomysial antibodies (EmA) have high specificity for coeliac disease and may facilitate case-finding by clinicians other than gastroenterologists. We assessed the appropriateness and diagnostic yield of of requests for EmA by primary care general practitioners in a defined geographic area of Northern Ireland. Methods: We identified patients who had EmA examination requests by their general practitioners during 1994-1996. Individual patient questionnaires were posted to the general practitioners concerned, seeking information on indications for testing, management after the result, and final diagnosis. We compared new patient diagnosis rates in two catchment areas, one served by a large district general hospital with, and the other by smaller hospitals without, a medical gastroenterology facility. Results: A total of 239 patients had coeliac profile testing by 69 of 177 general practitioners in the area. Data were available for 181 patients not previously known to have coeliac disease, of whom 20 (11%) had EmA. All EmA-positive patients were referred to hospital, where 19 underwent small-bowel biopsy, which confirmed coeliac disease in all 19. Only 7 (35%) of the 20 had diarrhoea, and there was no significant difference in EmA prevalence among patients tested with and without diarrhoea. Although the mean number of new patients (per 100,000 population annually) diagnosed by biopsy was 11 at the large hospital compared with 5 elsewhere, the numbers identified by EmA in general practice for the 2 catchment areas were similar (2 and 3, respectively). Conclusion: General practitioners have an important role in the identification of patients with coeliac disease, particularly where there is no local medical gastroenterology facility, and this is facilitated by EmA testing. [ABSTRACT FROM AUTHOR]

Interactions between arsenic (As) and selenium (Se) at the metaboliclevel are multifaceted and complex. These interactions are of practical significance because populations in various parts of the world are simultaneously exposed to inorganic As in drinking water and Se mainly in the diet at varying levels. The primary goal of this study wasto investigate whether differing dietary Se status would alter the profile of urinary metabolites or their time course for elimination after exposure to arsenate [As(V)]. Weanling female B6C3F1 mice were maintained for 28 d on either a control diet of powdered rodent meal sufficient in Se (A, 0.2 ppm) or Torula yeast-based (TYB) diets deficient (B, 0.02 ppm Se), sufficient (C, 0.2 ppm Se), or excessive (13, 2.0 ppm Se) in Se; mice then received by oral gavage 5 mg (As)/kg as sodium [73As] arsenate. The time course for elimination of total arsenic and metabolites in urine was measured over a 48-h period, and total arsenic was determined in feces and tissues at48 h. Mice on the Se excess diet excreted a significantly higher percentage of urinary As as inorganic As, with a significantly decreasedratio of organic to inorganic As compared to Se-sufficient mice, suggesting that As methylation was decreased. Mice on the Se-deficient diet appeared to eliminate As(V), arsenite, and dimethylarsinic acid (DMA) in urine more slowly than Se-sufficient mice; however, further studies are required to confirm this finding. Mice on the Se-sufficient meal diet (A) excreted significantly less (by percent) arsenate-derived radioactivity in urine and more in feces compared to mice on theSe-sufficient TYB diet (C), with total elimination being similar forboth groups. This indicates that mice on the meal diet absorbed significantly less As(V) than mice on the TYB diet, and this may be due to more fiber or 'bulk' in the meal diet. This finding emphasizes the importance of considering dietary composition when interpreting and compari [ABSTRACT FROM AUTHOR]