Longitudinal study on the use of dried blood spots for home monitoring in children after kidney transplantation.

The use of DBSs for home monitoring has been limited due to unsatisfactory blood sampling and analytical difficulties. The aim of this longitudinal feasibility trial was to assess the utility of DBS to monitor TAC and Cr at home in transplant recipients. A total of 30 participants (2-21 years, mean±SD, 13.6±5.4 year) were enrolled over 12 months. Eighteen were males. Monthly DBS samples were obtained at home and mailed to the central laboratory for analysis of TAC and Cr. Nineteen patients completed the study, and 216 cards were received in the laboratory from a total of 279 cards expected, with 416/519 (80%) blood spots being suitable for analysis. We found a high correlation between blood TAC and Cr levels by DBS and the clinical laboratory, R2 =.81 and .95, respectively. Fifteen parents and 15 youth completed measures of satisfaction with and preference for DBS testing. All but one parent/caregiver and youth reported satisfaction and preference for this method of testing over laboratory blood draws. We conclude that home DBS monitoring is a feasible method to monitor TAC and Cr in pediatric transplant recipients.

Reformulations of well-known active ingredients in the topical treatment of psoriasis vulgaris can improve clinical outcomes for patients.

Although the majority of patients with psoriasis vulgaris are treated exclusively with topical therapies, research to develop more effective topical therapies that are associated with higher patient satisfaction has lagged behind the development of systemic agents. The aim of this literature review was to determine whether there is documented evidence that applying an innovative approach to improving the formulation of active ingredients commonly used in the topical treatment of psoriasis can have a positive effect on clinical outcomes and patient-reported outcomes (PROs). The Embase and PubMed databases were searched for articles published between 2001 and 2016 that made direct head-to-head comparisons of different formulations of an active pharmaceutical ingredient (API), focusing on clinical outcomes and PROs. In total, 22 publications on APIs or API combinations met the eligibility criteria (19 head-to-head clinical trials, one pooled analysis, one health-economic modelling study and one systematic review). Significant clinical benefit associated with the use of a reformulated API over an older formulation was reported in three trials of clobetasol propionate, one trial of calcipotriol, three trials of betamethasone and five trials/pooled analyses of calcipotriol/calcipotriene + betamethasone dipropionate (Cal/BD) formulations. Significantly improved PROs associated with the use of a reformulated API over an older formulation were reported in three trials of clobetasol propionate, one trial of betamethasone valerate and two trials of Cal/BD formulations. These results demonstrate that the innovative reformulation of APIs used in the treatment of psoriasis can produce therapies that attain significantly improved clinical outcomes and PROs. This suggests that improvement in topical therapy for psoriasis need not only to be achieved by the identification of new targets and the development of new APIs, but that improvement in the vehicle used to deliver existing APIs has the potential to result in significant clinical and patient benefits.

Repeat patient testing-quality control compared to commercial quality control material for the Sysmex XT-2000iV hematology analyzer in a multi-site veterinary laboratory.

BACKGROUND: Quality control material (QCM) for hematology in veterinary laboratories is limited, and repeat patient testing quality control (RPT-QC) is an alternative method using excess matrix-specific samples. OBJECTIVES: This study aimed to determine if median differences between RPT-QC analyses for each time interval for RBC, HGB, HCT, and WBC were the same, determine if unified RPT-QC limits can be applied to a network of veterinary laboratories, compare the performance of RPT-QC to commercial QCM for the reference analyzer and evaluate the experience over a 4 month period and design, improve and implement an automated spreadsheet for RPT-QC data management. METHODS: The potential to unify individual analyzer RPT-QC limits for red blood cells (RBC), hematocrit (HCT), hemoglobin (HGB), and white blood cells (WBC) on multi-site Sysmex XT-2000-iV analyzers was explored by a difference of means test and confidence interval determination for the median difference for each network analyzer in comparison to the network reference analyzer. User experience of an automated RPT-QC data management Excel spreadsheet was collected by user feedback during monthly meetings. Numbers of out-of-control results and the root causes for these for RPT-QC were compared against those of a commercial QCM over a 4-month period. RESULTS: Differences between individual analyzer RPT-QC limits were too large to allow for unification of network limits. The automated spreadsheet successfully highlighted out-of-control events for RPT-QC. Trends or shifts were more frequent for commercial QCM based on observed performance and a 1-2.5 s QC rule than for RPT-QC. Following routine troubleshooting, RPT-QC out-of-control events were resolved with an alternative RPT-QC sample indicating random error associated with excessive deterioration. Use of an automated spreadsheet for recording RPT-QC, documentation and troubleshooting of out-of-control events, and collating monthly summary calculations were considered an asset in laboratory quality management. CONCLUSIONS: RPT-QC can be successfully implemented and integrated into a multi-site veterinary laboratory. Individual analyzer RPT-QC limit generation is recommended. The deterioration of commercial QCM caused shifts or trends in QC results, which initiated more repeat analyses and investigations than did RPT-QC.

Response of diademed sifaka (Propithecus diadema) to fosa (Cryptoprocta ferox) predation in the Betampona Strict Nature Reserve, Madagascar.

Large-bodied mammals living in fragmented habitats are at higher risk of extinction, and such risk can be influenced by ecological factors such as predator-prey system dynamics. These dynamics can be particularly complex for conservation management when one endangered species preys on another endangered species in an isolated or poor-quality habitat. Here we describe predation events observed over 19 months that involved two threatened species: the largest carnivore in Madagascar, the fosa (Cryptoprocta ferox), and three groups of diademed sifaka (Propithecus diadema) in the Betampona Strict Nature Reserve. This site is a 22 km2 low-altitude rainforest that is surrounded by agricultural land and isolated from larger forest corridors. We aim to (1) assess the behavioral changes of P. diadema in response to fosa attacks and identify any antipredator strategies that they adopted, and (2) quantify the frequency of fosa attacks and the predation impact on the sifaka population. We report five direct observations of fosa predation attempts (one successful), the discovery of a dead sifaka with evidence of fosa predation, and the disappearance of three individuals. We describe the observed attacks and compare the sifaka activity budgets and movement patterns before and after the events. To escape the predator, sifakas fled short distances, hid, and remained vigilant. The impact of predation, combined with low reproductive rates and potentially high inbreeding of this isolated diademed sifaka population, could affect the survival of this species in Betampona. Given the compounding effects of habitat isolation and high hunting pressure, community-specific conservation strategies should incorporate predator-prey dynamics via longitudinal monitoring of predator and prey population densities and quantifying the predation pressure between them.

Analytical performance evaluation of two automated urine sediment analysers using two levels of commercially available quality control material.

OBJECTIVES: Evaluate the in-clinic performance of point-of-care sediment analysers, Analyzer V (Vetscan SA, Abaxis) and Analyzer S (SediVue DX, IDEXX), using assayed, bilevel (2 concentrations) urine quality control material to determine if instrument specifications are acceptable for semi-quantitative clinical urine sediment analysis. MATERIALS AND METHODS: Accuracy, precision and clinical utility of Analyzer V and Analyzer S measurements were evaluated using a bilevel, assayed quality control material in 23 veterinary practices. RESULTS: Photomicrographs taken by the instruments facilitated manual review and quality assessment. Analyzer V and Analyzer S under-identified the presence of cystine crystals with 83 and 13% inaccuracy in the positive quality control material, respectively. Analyzer V and Analyzer S over-reported bacteria in the sterile quality control material with 82 and 94% specificity, respectively. Analyzer V and Analyzer S reported RBCs and WBCs within manufacturer specifications with excellent sensitivity (93 to 100%) and specificity (100%). CLINICAL SIGNIFICANCE: Additional improvement is needed to better classify crystal types and reduce false positives for bacteria before clinical use. While normal samples can generally be trusted, a manual review of abnormal samples is required to ensure that clinically important urine components are correctly evaluated. Future studies should evaluate the performance of these instruments with species-specific urine sediment.

Analytical performance evaluation of two automated urine chemistry analysers using two levels of commercially available quality control material.

OBJECTIVE: Evaluate two point-of-care urine chemistry analysers, VetScan SA and VetLab UA using assayed, bilevel (two concentrations) urine quality control material to determine if performance is acceptable for semiquantitative clinical urine chemistry analysis. MATERIALS AND METHODS: Normal and abnormal urine quality control material sent to 23 veterinary practices was evaluated three times by each clinic on in-clinic automated urinalysis instruments. Accuracy, precision and clinical utility were evaluated. RESULTS: Normal urine quality control material: Results for blood, glucose, ketones and bilirubin were 100% accurate and precise for both analysers, and pH values were accurately acidic to neutral. However, pH from VetScan SA had clinically significant negative bias. Abnormal urine quality control material: VetScan SA: blood, microalbumin and bilirubin were 100% accurate; glucose, ketones, and protein demonstrated ≤10% inaccuracy; pH demonstrated 34% inaccuracy. VetLab UA: blood, ketones and bilirubin were 100% accurate; glucose and protein demonstrated ≤10% inaccuracy; pH was 100% accurately neutral to alkaline. CLINICAL SIGNIFICANCE: VetScan SA had marked negative pH bias versus VetLab UA resulting in clinically significant, overly acidic results. Specific gravity, nitrite, and leukocyte test pads should not be used. Both instruments had excellent performance in normal quality control material. While blood, glucose, protein and bilirubin are correctly identified as present in abnormal quality control material, exact concentrations cannot be interpreted due to imprecision. Only semiquantitative results, not numerical values implying quantification, should be reported from urine test strips.

Choice between food and cocaine or fentanyl reinforcers under fixed and variable schedules in female and male rhesus monkeys.

RATIONALE: Illicit drugs may be unpredictable in terms of the time and effort required to obtain them, and this can be modeled with variable- (VR) vs. fixed-ratio (FR) schedules. In a recent experiment (Zamarripa et al. 2023), the potency of cocaine to maintain choice was greatest under a VR (compared with a FR) when food was available under a FR schedule. OBJECTIVES: The goal of the current study was to extend prior choice results with VR vs. FR schedules to a more efficient procedure with cocaine or fentanyl vs. food. Furthermore, the FR schedule of food delivery was manipulated to determine whether increased drug choice under a VR (compared with a FR) schedule depends on the size of the schedule of nondrug reinforcement. METHODS: Adult female (n = 2) and male (n = 4) monkeys chose between cocaine (0-30 µg/kg/injection) or fentanyl (0-1.0 µg/kg/injection) and food (2 pellets/delivery) under a 5-component procedure. In different conditions, food was available under a FR 25, 50, or 100 and cocaine or fentanyl were available under FR or VR 100 schedules. RESULTS: Cocaine's potency to maintain choice was greatest under a VR 100 (compared with FR 100) when food was available under a FR 50 or 100, and fentanyl's potency to maintain choice was generally greatest under a VR 100 (compared with FR 100) when food was available under a FR 25 or 100. However, outcomes between FR and VR schedules with fentanyl were less robust compared with cocaine. CONCLUSION: Variability in the time and effort required to obtain illicit drugs could contribute to excessive allocation of behavior toward drug use at the expense of more predictable nondrug alternatives, supporting treatment or policies aimed at making drug access more predictable through agonist medications or a safe supply. The impact of variable requirements on drug choice may be reduced if nondrug reinforcers are relatively less costly, supporting the use of low-cost reinforcers in behavioral therapies like contingency management.

Evidence that chytrids dominate fungal communities in high-elevation soils.

Periglacial soils are one of the least studied ecosystems on Earth, yet they are widespread and are increasing in area due to retreat of glaciers worldwide. Soils in these environments are cold and during the brief summer are exposed to high levels of UV radiation and dramatic fluctuations in moisture and temperature. Recent research suggests that these environments harbor immense microbial diversity. Here we use sequencing of environmental DNA, culturing of isolates, and analysis of environmental variables to show that members of the Chytridiomycota (chytrids) dominate fungal biodiversity and perhaps decomposition processes in plant-free, high-elevation soils from the highest mountain ranges on Earth. The zoosporic reproduction of chytrids requires free water, yet we found that chytrids constituted over 70% of the ribosomal gene sequences of clone libraries from barren soils of the Himalayas and Rockies; by contrast, they are rare in other soil environments. Very few chytrids have been cultured, although we were successful at culturing chytrids from high-elevation sites throughout the world. In a more focused study of our sites in Colorado, we show that carbon sources that support chytrid growth (eolian deposited pollen and microbial phototrophs) are abundant and that soils are saturated with water for several months under the snow, thus creating ideal conditions for the development of a chytrid-dominated ecosystem. Our work broadens the known biodiversity of the Chytridomycota, and describes previously unsuspected links between aquatic and terrestrial ecosystems in alpine regions.

Cross-Sectional Survey of Graduate Clinical Nutrition Students Describing Dietary Choices and Recommendations.

Objectives: Little data exists describing the dietary habits of nutrition students, including whether students' personal dietary choices influence their clinical recommendations. Study objectives were to: (1) Identify common dietary choices made by nutrition students, (2) determine students' rationale for choosing or avoiding specific diets, (3) identify key factors used to make dietary recommendations.Methods: An anonymous online survey was distributed to graduate-level clinical nutrition students who were attending five American universities. Data collected included demographics, current diet, reasons for following the current diet, reasons for recommending diets, and degree completion status. Percentage of diets chosen and rationale for dietary decisions were compared. Diets chosen and recommended were stratified and compared by degree completion status via chi-square test.Results: 208 participants completed the survey. The top diets students reported following were Whole Foods/Unprocessed (49%) and Gluten-Free (16%), followed by Vegan/Vegetarian (13%) and Paleo (12.5%). The top reasons identified for choosing a personal diet were health optimization and food allergy/intolerance/sensitivity. The top factors used to make dietary recommendations were clients' preferences/resources and results of laboratory testing. A Whole Foods/Unprocessed diet was also selected by the largest proportion of students as one they would recommend to clients-97% of students early in their program and 98.3% of students late in their program would recommend it to a client.Conclusion: A Whole Foods/Unprocessed diet was the most followed diet and the one most likely to be recommended to future clients, irrespective of students' degree completion progress.

Phylogeography of microbial phototrophs in the dry valleys of the high Himalayas and Antarctica.

High-elevation valleys in dry areas of the Himalayas are among the most extreme, yet least explored environments on Earth. These barren, rocky valleys are subjected to year-round temperature fluctuations across the freezing point and very low availability of water and nutrients, causing previous workers to hypothesize that no photoautotrophic life (primary producers) exists in these locations. However, there has been no work using modern biogeochemical or culture-independent molecular methods to test the hypothesis that photoautotrophs are absent from high Himalayan soil systems. Here, we show that although microbial biomass levels are as low as those of the Dry Valleys of Antarctica, there are abundant microbial photoautotrophs, displaying unexpected phylogenetic diversity, in barren soils from just below the permanent ice line of the central Himalayas. Furthermore, we discovered that one of the dominant algal clades from the high Himalayas also contains the dominant algae in culture-independent surveys of both soil and ice samples from the Dry Valleys of Antarctica, revealing an unexpected link between these environmentally similar but geographically very distant systems. Phylogenetic and biogeographic analyses demonstrated that although this algal clade is globally distributed to other high-altitude and high-latitude soils, it shows significant genetic isolation by geographical distance patterns, indicating local adaptation and perhaps speciation in each region. Our results are the first to demonstrate the remarkable similarities of microbial life of arid soils of Antarctica and the high Himalayas. Our findings are a starting point for future comparative studies of the dry valleys of the Himalayas and Antarctica that will yield new insights into the cold and dry limits to life on Earth.

Increased detection in Australia and Singapore of a novel influenza A(H1N1)2009 variant with reduced oseltamivir and zanamivir sensitivity due to a S247N neuraminidase mutation.

A novel influenza A(H1N1)2009 variant with mildly reduced oseltamivir and zanamivir sensitivity has been detected in more than 10% of community specimens in Singapore and more than 30% of samples from northern Australia during the early months of 2011. The variant, which has also been detected in other regions of the Asia-Pacific, contains a S247N neuraminidase mutation. When combined with the H275Y mutation, as detected in an oseltamivir-treated patient, the dual S247N+H275Y mutant had extremely high oseltamivir resistance.

Oseltamivir-resistant influenza viruses circulating during the first year of the influenza A(H1N1) 2009 pandemic in the Asia-Pacific region, March 2009 to March 2010.

During the first year of the influenza A(H1N1) 2009 pandemic, unprecedented amounts of the neuraminidase inhibitors, predominantly oseltamivir, were used in economically developed countries for the treatment and prophylaxis of patients prior to the availability of a pandemic vaccine. Due to concerns about the development of resistance, over 1,400 influenza A(H1N1) 2009 viruses isolated from the Asia-Pacific region during the first year of the pandemic (March 2009 to March 2010) were analysed by phenotypic and genotypic assays to determine their susceptibility to the neuraminidase inhibitors. Amongst viruses submitted to the World Health Organization Collaborating Centre for Reference and Research in Melbourne, Australia,oseltamivir resistance was detected in 1.3% of influenza A(H1N1) 2009 strains from Australia and 3.1% of strains from Singapore, but none was detected in specimens received from other countries in Oceania or south-east Asia, or in east Asia. The overall frequency of oseltamivir resistance in the Asia-Pacific region was 16 of 1,488 (1.1%). No zanamivir-resistant viruses were detected. Of the 16 oseltamivir-resistant isolates detected, nine were from immunocompromised individuals undergoing oseltamivir treatment and three were from immunocompetent individuals undergoing oseltamivir treatment. Importantly, four oseltamivir-resistant strains were from immunocompetent individuals who had not been treated with oseltamivir, demonstrating limited low-level community transmission of oseltamivir-resistant strains. Even with increased use of oseltamivir during the pandemic, the frequency of resistance has been low, with little evidence of community-wide spread of the resistant strains. Nevertheless, prudent use of the neuraminidase inhibitors remains necessary, as does continued monitoring for drug-resistant influenza viruses.

Acute Responses of Core Muscle Activity during Bridge Exercises on the Floor vs. the Suspension System.

This study aimed to compare the neuromuscular activation of selected core musculature in supine and prone bridge exercises under stable versus suspended conditions. Forty-three healthy male participants were recruited to measure the electromyographic activities of the rectus abdominis (RA), lumbar multifidus (LM), thoracic erector spinae (TES), rectus femoris (RF), gluteus maximus (GM), and biceps femoris (BF) during supine and prone bridge exercises under six conditions: control, both arms and feet on the floor (Pronecon and Supinecon); arms on the floor and feet on the suspension system (Prone-Feetsuspension and Supine-Feetsuspension); and arms on the suspension system and feet on the floor (Prone-Armsuspension and Supine-Armsuspension). Prone-Armsuspension yielded significantly higher activities in the RA, RF, TES, and LM than Prone-Feetsuspension (p < 0.01) and Pronecon (p < 0.001). Moreover, Supine-Feetsuspension elicited significantly higher activities in the RA, RF, TES, LM, and BF than Supine-Armsuspension (p < 0.01) and Supinecon (p < 0.001). Furthermore, Supine-Feetsuspension elicited significantly higher activities in the RF, TES, and BF than Supinecon (p < 0.01). Therefore, if the RA and/or RF were the target training muscles, then Prone-Armsuspension was recommended. However, if the TES, LM, and/or BF were the target training muscles, then Supine-Feetsuspension was recommended.

Quantification of observable behaviors induced by typical and atypical kappa-opioid receptor agonists in male rhesus monkeys.

RATIONALE: Kappa-opioid receptor (KOR) agonists are antinociceptive but have side effects that limit their therapeutic utility. New KOR agonists have been developed that are fully efficacious at the KOR but may produce fewer or reduced side effects that are typical of KOR agonists. OBJECTIVES: We determined behavioral profiles for typical and atypical KOR agonists purported to differ in intracellular-signaling profiles as well as a mu-opioid receptor (MOR) agonist, oxycodone, using a behavioral scoring system based on Novak et al. (Am J Primatol 28:124-138, 1992, Am J Primatol 46:213-227, 1998) and modified to quantify drug-induced effects (e.g., Duke et al. J Pharmacol Exp Ther 366:145-157, 2018). METHODS: Six adult male rhesus monkeys were administered a range of doses of the typical KOR agonists, U50-488H (0.0032-0.1 mg/kg) and salvinorin A (0.00032-0.01 mg/kg); the atypical KOR agonists, nalfurafine (0.0001-0.001 mg/kg) and triazole 1.1 (0.01-0.32 mg/kg); the MOR agonist, oxycodone (0.0032-0.32 mg/kg); and as controls, cocaine (0.032-0.32 mg/kg) and ketamine (0.32-10 mg/kg). For time-course determinations, the largest dose of each KOR agonist or MOR agonist was administered across timepoints (10-320 min). In mixture conditions, oxycodone (0.1 mg/kg) was followed by KOR-agonist administration. RESULTS: Typical KOR agonists produced sedative-like and motor-impairing effects. Nalfurafine was similar to typical KOR agonists on most outcomes, and triazole 1.1 produced no effects on its own except for reducing scratch during time-course determinations. In the mixture, all KOR agonists reduced oxycodone-induced scratching, U50-488H and nalfurafine reduced species-typical activity, and U50-488H increased rest/sleep posture. CONCLUSIONS: Atypical "biased" KOR agonists produce side-effect profiles that are relatively benign (triazole 1.1) or reduced (nalfurafine) compared to typical KOR agonists.

Selection of mammalian cells resistant to a chloramphenicol analog.

This study describes the selection and preliminary characterization of mammalian cells resistant to 100 mug Tevenel/ml. Tevenel, the sulfamoyl analog of chloramphenicol, is a specific inhibitor of mitochondrial protein synthesis. After growth in suspension culture for 5 days in 100 mug Tevenel/ml and subsequent plating in 100 mug Tevenel/ml, LMTK- cells yielded resistant clones. As a control, L cells treated identically yielded no clones. Three resistant clones were chosen for study. Each resistant cell line had an identical growth rate in the presence and absence of 100 mug Tevenel/ml. By plating efficiency analysis, the resistant cells were found to be cross-resistant to D-chloramphenicol. The change responsible for resistance was found to be stable for at least 100 generations in the absence of the drug. Protein synthesis by isolated mitochondria of resistant cells was found to be less inhibited by concentrations of both Tevenel and D-chloramphenicol up to 200 mug/ml than the protein synthesis by LMTK- mitochondria. This resistance in vitro was not changed by incubation of the mitochondria in 0.01% Triton X-100.

Topogenesis of mitochondrial inner membrane uncoupling protein. Rerouting transmembrane segments to the soluble matrix compartment.

Brown adipose tissue uncoupling protein (UCP), an integral polytopic protein of the mitochondrial inner membrane, is composed of at least six transmembrane segments whose net hydrophobic character derives from paired amphiphilic helices. The protein is synthesized in the cytoplasm as a polypeptide (307 amino acids) lacking a cleavable targeting (signal) peptide. Deletion mutagenesis and fusion protein constructions revealed the existence of at least two import signals: one lying between UCP precursor amino acids 13-105 and the other downstream of position 101. The former resulted in both targeting and membrane insertion of a fusion protein, whereas the latter targeted UCP 102-307 into the organelle but failed to result in membrane insertion. When a strong matrix-targeting signal derived from precarbamoyl phosphate synthetase was fused to UCP amino acids 169-307 or 52-307 (containing three and five transmembrane domains, respectively), the fusion proteins were efficiently imported to the soluble matrix compartment where correct signal cleavage took place. We suggest that assembly of UCP into the inner membrane follows a coordinate insertion pathway for integration and may use more than one signal sequence to achieve this. In this respect, it might share certain mechanistic features with the insertion of polytopic proteins into the endoplasmic reticulum. The data also suggest, however, that integration of the amino-terminal third of UCP into the inner membrane may be required to help or enhance insertion of the remaining UCP transmembrane domains.

Climate change as the dominant control on glacial-interglacial variations in C3 and C4 plant abundance.

Although C4 plant expansions have been recognized in the late Miocene, identification of the underlying causes is complicated by the uncertainties associated with estimates of ancient precipitation, temperature, and partial pressure of atmospheric carbon dioxide (PCO2). Here we report the carbon isotopic compositions of leaf wax n-alkanes in lake sediment cores from two sites in Mesoamerica that have experienced contrasting moisture variations since the last glacial maximum. Opposite isotopic trends obtained from these two sites indicate that regional climate exerts a strong control on the relative abundance of C3 and C4 plants and that in the absence of favorable moisture and temperature conditions, low PCO2 alone is insufficient to drive an expansion of C4 plants.

Microbial activity and diversity during extreme freeze-thaw cycles in periglacial soils, 5400 m elevation, Cordillera Vilcanota, Perú.

High-elevation periglacial soils are among the most extreme soil systems on Earth and may be good analogs for the polar regions of Mars where oligotrophic mineral soils abut with polar ice caps. Here we report on preliminary studies carried out during an expedition to an area where recent glacial retreat has exposed porous mineral soils to extreme, daily freeze-thaw cycles and high UV fluxes. We used in situ methods to show that inorganic nitrogen (NO(3) (-) and NH(4) (+)) was being actively cycled even during a period when diurnal soil temperatures (5 cm depth) ranged from -12 to 27 degrees C and when sub-zero, soil cooling rates reached 1.8 degrees C h(-1) (the most rapid soil cooling rates recorded to date). Furthermore, phylogenetic analyses of microbial phylotypes present at our highest sites (5410 m above sea level) showed the presence of nitrifying bacteria of the genus Nitrospira and newly discovered nitrite-oxidizing Betaproteobacteria. These soils were overwhelmingly dominated (>70% of phylotypes) by photosynthetic bacteria that were related to novel cyanobacteria previously found almost exclusively in other plant-free, high-elevation soils. We also demonstrated that soils from our highest sites had higher potential for mineralizing glutamate and higher microbial biomass than lower elevation soils that had been more recently covered by ice. Overall, our findings indicate that a diverse and robustly functioning microbial ecosystem is present in these previously unstudied high-elevation soils.

Self-administration of benzodiazepine and cocaine combinations by male and female rhesus monkeys in a choice procedure: role of α1 subunit-containing GABAA receptors.

RATIONALE: Compounds lacking efficacy at the α1 subunit-containing GABAA (α1GABAA) receptor appear to have reduced abuse potential compared with those having measurable efficacy at this receptor, though their self-administration in nonhuman primates is dependent upon past drug experience. OBJECTIVES: We used a drug vs. drug choice procedure to evaluate the hypothesis that L-838,417, a compound lacking efficacy at αGABAA receptors, would not enhance cocaine choice in monkeys trained to self-administer cocaine. We also hypothesized that zolpidem, a compound with preferential modulation of ⍺1GABAA receptors and midazolam, a nonselective benzodiazepine, would enhance cocaine choice in this procedure. METHODS: One female and three male rhesus monkeys chose between cocaine alone (0.1 mg/kg/injection) vs. the same dose of cocaine combined with midazolam (0.003-0.1 mg/kg/injection), zolpidem (0.003-0.3 mg/kg/injection), or L-838-417 (0.01-0.1 mg/kg/injection). In addition, we evaluated choice between saline and L-838,417 at select doses to determine whether L-838,417 would function as a reinforcer on its own. RESULTS: Consistent with our hypotheses, midazolam- and zolpidem-cocaine mixtures were chosen over cocaine alone at sufficiently high doses. However, L-838,417-cocaine mixtures also were chosen over cocaine alone in three of four subjects with at least one dose. When available alone vs. saline, L-838,417 did not function as a reinforcer in any subject. CONCLUSION: Compounds that lack efficacy at α1GABAA receptors may have low abuse potential compared to classic benzodiazepines, but self-administration of these compounds is context-dependent.

Biological variation of routine haematology and biochemistry measurands in the horse.

BACKGROUND: Clinical pathology results are typically interpreted by referring to population-based reference intervals. The use of individualised (subject-based) reference intervals is more appropriate for measurands with a high degree of variation between individuals. OBJECTIVES: To determine the biological variation of routinely analysed equine haematology and biochemistry measurands and calculate indices of individuality and reference change values which enable production of individualised reference intervals, in a group of healthy, privately owned horses. STUDY DESIGN: In a prospective cohort study, thirty-nine privately owned horses were sampled by jugular venipuncture for analysis of haematology and biochemistry measurands at weekly intervals for 6 weeks. METHODS: Haematology was analysed on the day of collection. Serum was frozen and biochemistry analyses performed on thawed samples. Duplicate results were obtained and the coefficient of variation was calculated for analytical variation, within-subject variation and between-subject variation. The index of individuality and reference change value were derived for each measurand. RESULTS: Haematology (red blood cell count, mean corpuscular haemoglobin and mean cell volume) and biochemistry measurands (total protein, globulins, albumin, gamma-glutamyl transferase, aspartate aminotransferase) demonstrated high individuality, indicating that individualised reference intervals are more appropriate for evaluation of these measurands. Two haematology (mean corpuscular haemoglobin concentration and platelets) and three biochemistry measurands (chloride, glucose and sodium) had low individuality, indicating that the use of traditional population-based reference intervals is appropriate for these measurands. Remaining measurands had intermediate individuality suggesting interpretation of the reference change value should occur with consideration of the population-based reference interval. MAIN LIMITATIONS: The use of privately owned horses, variable management and environmental factors. CONCLUSIONS: The use of individualised reference intervals is justified for many measurands in horses, supporting the use of serial sampling, consideration of biological variation and application of reference change values for improved clinical decision making and patient management in equine practice.