Effects of the glucocorticoid antagonist, mifepristone, on the consequences of withdrawal from long term alcohol consumption

BACKGROUND: Studies were carried out to test the hypothesis that administration of a glucocorticoid Type II receptor antagonist, mifepristone (RU38486), just prior to withdrawal from chronic alcohol treatment, would prevent the consequences of the alcohol consumption and withdrawal in mice. MATERIALS AND METHODS: The effects of administration of a single intraperitoneal dose of mifepristone were examined on alcohol withdrawal hyperexcitability. Memory deficits during the abstinence phase were measured using repeat exposure to the elevated plus maze, the object recognition test, and the odor habituation/discrimination test. Neurotoxicity in the hippocampus and prefrontal cortex was examined using NeuN staining. RESULTS: Mifepristone reduced, though did not prevent, the behavioral hyperexcitability seen in TO strain mice during the acute phase of alcohol withdrawal (4 hours to 8 hours after cessation of alcohol consumption) following chronic alcohol treatment via liquid diet. There were no alterations in anxiety-related behavior in these mice at 1 week into withdrawal, as measured using the elevated plus maze. However, changes in behavior during a second exposure to the elevated plus maze 1 week later were significantly reduced by the administration of mifepristone prior to withdrawal, indicating a reduction in the memory deficits caused by the chronic alcohol treatment and withdrawal. The object recognition test and the odor habituation and discrimination test were then used to measure memory deficits in more detail, at between 1 and 2 weeks after alcohol withdrawal in C57/BL10 strain mice given alcohol chronically via the drinking fluid. A single dose of mifepristone given at the time of alcohol withdrawal significantly reduced the memory deficits in both tests. NeuN staining showed no evidence of neuronal loss in either prefrontal cortex or hippocampus after withdrawal from chronic alcohol treatment. CONCLUSIONS: The results suggest mifepristone may be of value in the treatment of alcoholics to reduce their cognitive deficits.

Actinobaculum schaalii an emerging pediatric pathogen?

Background Actinobaculum schaalii was first described as a causative agent for human infection in 1997. Since then it has mainly been reported causing urinary tract infections (UTI) in elderly individuals with underlying urological diseases. Isolation and identification is challenging and often needs molecular techniques. A. schaalii is increasingly reported as a cause of infection in humans, however data in children is very limited. Case presentation We present the case of an 8-month-old Caucasian boy suffering from myelomeningocele and neurogenic bladder who presented with a UTI. An ultrasound of the urinary tract was unremarkable. Urinalysis and microscopy showed an elevated leukocyte esterase test, pyuria and a high number of bacteria. Empiric treatment with oral co-trimoxazole was started. Growth of small colonies of Gram-positive rods was observed after 48 h. Sequencing of the 16S rRNA gene confirmed an A. schaalii infection 9 days later. Treatment was changed to oral amoxicillin for 14 days. On follow-up urinalysis was normal and urine cultures were negative. Conclusions A.schaalii is an emerging pathogen in adults and children. Colonization and subsequent infection seem to be influenced by the age of the patient. In young children with high suspicion of UTI who use diapers or in children who have known abnormalities of their urogenital tract, infection with A. schaalii should be considered and empiric antimicrobial therapy chosen accordingly.

Simply a nest? Effects of different enrichments on stereotypic and anxiety-related behaviour in mice

Improving the home cages of laboratory mice by environmental enrichment has been widely used to reduce cage stereotypies and anxiety-related behaviour in behavioural tests. However, enrichment studies differ substantially in type, complexity and variation of enrichments. Therefore, it is unclear whether success depends on specific enrichment items, environmental complexity, or novelty associated with enrichment. The aim of this study was therefore to dissociate the effects of environmental complexity and novelty on stereotypy development and compare these effects with the provision of nesting material alone. Thus, 54 freshly weaned male ICR (CD-1) mice were pairwise allocated to standard laboratory cages enriched in three different ways (n = 18 per group). Treatment 1 consisted of cotton wool as nesting material. Treatments 2 and 3 were structurally more complex, including a shelter and a climbing structure as additional resources. To render complexity and novelty independent of the specific enrichment items, three shelters (cardboard house, plastic tunnel, red plastic house) and three climbing structures (ladder, rope, wooden bars) were used to create nine different combinations of enrichment. In treatment 2 (complexity), each pair of mice was assigned to a different combination that remained constant throughout 9 weeks, whereas in treatment 3 (novelty), each pair of mice was exposed to all 9 combinations in turn by changing them weekly in a pseudorandom order. After 9 weeks, stereotypic behaviour in the home cage was assessed from video recordings, and anxiety-related behaviour was assessed in two behavioural tests (elevated zero-maze, open-field). However, no significant differences in stereotypy scores and no consistent differences in anxiety-related behaviours were found between the three groups. These findings indicate that within standard laboratory cages neither complexity nor novelty of simple enrichments have additional effects on stereotypic and anxiety-related behaviour beyond those of adequate nesting material. (C) 2011 Elsevier B.V. All rights reserved.

Elevated level of metabotropic glutamate receptor 2/3 in the prefrontal cortex in major depression

Clinical, postmortem and preclinical research strongly implicates dysregulation of glutamatergic neurotransmission in major depressive disorder (MDD). Recently, metabotropic glutamate receptors (mGluRs) have been proposed as attractive targets for the discovery of novel therapeutic approaches against depression. The aim of this study was to examine mGluR2/3 protein levels in the prefrontal cortex (PFC) from depressed subjects. In addition, to test whether antidepressants influence mGluR2/3 expression we also studied levels of mGluR2/3 in fluoxetine-treated monkeys. Postmortem human prefrontal samples containing Brodmann's area 10 (BA10) were obtained from 11 depressed and 11 psychiatrically healthy controls. Male rhesus monkeys were treated chronically with fluoxetine (dose escalated to 3mg/kg, p.o.; n=7) or placebo (n=6) for 39 weeks. The mGluR2/3 immunoreactivity was investigated using Western blot method. There was a robust (+67%) increase in the expression of the mGlu2/3 protein in the PFC of depressed subjects relative to healthy controls. The expression of mGlu2/3 was unchanged in the PFC of monkeys treated with fluoxetine. Our findings provide the first evidence that mGluR2/3 is elevated in the PFC in MDD. This observation is consistent with reports showing that mGluR2/3 antagonists exhibit antidepressant-like activity in animal models and demonstrates that these receptors are promising targets for the discovery of novel antidepressants.

Nanoparticle-based test measures overall propensity for calcification in serum

Vascular and soft tissue calcification contributes to cardiovascular morbidity and mortality in both the general population and CKD. Because calcium and phosphate serum concentrations are near supersaturation, the balance of inhibitors and promoters critically influences the development of calcification. An assay that measures the overall propensity for calcification to occur in serum may have clinical use. Here, we describe a nanoparticle-based assay that detects, in the presence of artificially elevated calcium and phosphate concentrations, the spontaneous transformation of spherical colloidal primary calciprotein particles (CPPs) to elongate crystalline secondary CPPs. We used characteristics of this transition to describe the intrinsic capacity of serum to inhibit the precipitation of calcium and phosphate. Using this assay, we found that both the sera of mice deficient in fetuin-A, a serum protein that inhibits calcification, and the sera of patients on hemodialysis have reduced intrinsic properties to inhibit calcification. In summary, we developed a nanoparticle-based test that measures the overall propensity for calcification in serum. The clinical use of the test requires evaluation in a prospective study.

Presence of UV filters in surface water and the effects of phenylbenzimidazole sulfonic acid on rainbow trout (Oncorhynchus mykiss) following a chronic toxicity test

UV filters belong to a group of compounds that are used by humans and are present in municipal waste-waters, effluents from sewage treatment plants and surface waters. Current information regarding UV filters and their effects on fish is limited. In this study, the occurrence of three commonly used UV filters - 2-phenylbenzimidazole-5-sulfonic acid (PBSA), 2-hydroxy-4-methoxybenzophenone (benzophenone-3, BP-3) and 5-benzoyl-4-hydroxy-2-methoxy-benzenesulfonic acid (benzophenone-4, BP-4) - in South Bohemia (Czech Republic) surface waters is presented. PBSA concentrations (up to 13μgL(-1)) were significantly greater than BP-3 or BP-4 concentrations (up to 620 and 390ngL(-1), respectively). On the basis of these results, PBSA was selected for use in a toxicity test utilizing the common model organism rainbow trout (Oncorhynchus mykiss). Fish were exposed to three concentrations of PBSA (1, 10 and 1000µgL(-1)) for 21 and 42 days. The PBSA concentrations in the fish plasma, liver and kidneys were elevated after 21 and 42 days of exposure. PBSA increased activity of certain P450 cytochromes. Exposure to PBSA also changed various biochemical parameters and enzyme activities in the fish plasma. However, no pathological changes were obvious in the liver or gonads.

Genotype-specific risk factors for Staphylococcus aureus in Swiss dairy herds with an elevated yield-corrected herd somatic cell count

Bovine mastitis is a frequent problem in Swiss dairy herds. One of the main pathogens causing significant economic loss is Staphylococcus aureus. Various Staph. aureus genotypes with different biological properties have been described. Genotype B (GTB) of Staph. aureus was identified as the most contagious and one of the most prevalent strains in Switzerland. The aim of this study was to identify risk factors associated with the herd-level presence of Staph. aureus GTB and Staph. aureus non-GTB in Swiss dairy herds with an elevated yield-corrected herd somatic cell count (YCHSCC). One hundred dairy herds with a mean YCHSCC between 200,000 and 300,000cells/mL in 2010 were recruited and each farm was visited once during milking. A standardized protocol investigating demography, mastitis management, cow husbandry, milking system, and milking routine was completed during the visit. A bulk tank milk (BTM) sample was analyzed by real-time PCR for the presence of Staph. aureus GTB to classify the herds into 2 groups: Staph. aureus GTB-positive and Staph. aureus GTB-negative. Moreover, quarter milk samples were aseptically collected for bacteriological culture from cows with a somatic cell count ≥150,000cells/mL on the last test-day before the visit. The culture results allowed us to allocate the Staph. aureus GTB-negative farms to Staph. aureus non-GTB and Staph. aureus-free groups. Multivariable multinomial logistic regression models were built to identify risk factors associated with the herd-level presence of Staph. aureus GTB and Staph. aureus non-GTB. The prevalence of Staph. aureus GTB herds was 16% (n=16), whereas that of Staph. aureus non-GTB herds was 38% (n=38). Herds that sent lactating cows to seasonal communal pastures had significantly higher odds of being infected with Staph. aureus GTB (odds ratio: 10.2, 95% CI: 1.9-56.6), compared with herds without communal pasturing. Herds that purchased heifers had significantly higher odds of being infected with Staph. aureus GTB (rather than Staph. aureus non-GTB) compared with herds without purchase of heifers. Furthermore, herds that did not use udder ointment as supportive therapy for acute mastitis had significantly higher odds of being infected with Staph. aureus GTB (odds ratio: 8.5, 95% CI: 1.6-58.4) or Staph. aureus non-GTB (odds ratio: 6.1, 95% CI: 1.3-27.8) than herds that used udder ointment occasionally or regularly. Herds in which the milker performed unrelated activities during milking had significantly higher odds of being infected with Staph. aureus GTB (rather than Staph. aureus non-GTB) compared with herds in which the milker did not perform unrelated activities at milking. Awareness of 4 potential risk factors identified in this study guides implementation of intervention strategies to improve udder health in both Staph. aureus GTB and Staph. aureus non-GTB herds.

Elevated AST-to-platelet ratio index is associated with increased all-cause mortality among HIV-infected adults in Zambia.

BACKGROUND AND AIMS We investigated the association between significant liver fibrosis, determined by AST-to-platelet ratio index (APRI), and all-cause mortality among HIV-infected patients prescribed antiretroviral therapy (ART) in Zambia METHODS: Among HIV-infected adults who initiated ART, we categorized baseline APRI scores according to established thresholds for significant hepatic fibrosis (APRI ≥1.5) and cirrhosis (APRI ≥2.0). Using multivariable logistic regression we identified risk factors for elevated APRI including demographic characteristics, body mass index (BMI), HIV clinical and immunologic status, and tuberculosis. In the subset tested for hepatitis B surface antigen (HBsAg), we investigated the association of hepatitis B virus co-infection with APRI score. Using Kaplan-Meier analysis and Cox proportional hazards regression we determined the association of elevated APRI with death during ART. RESULTS Among 20,308 adults in the analysis cohort, 1,027 (5.1%) had significant liver fibrosis at ART initiation including 616 (3.0%) with cirrhosis. Risk factors for significant fibrosis or cirrhosis included male sex, BMI <18, WHO clinical stage 3 or 4, CD4+ count <200 cells/mm(3) , and tuberculosis. Among the 237 (1.2%) who were tested, HBsAg-positive patients had four times the odds (adjusted odds ratio, 4.15; 95% CI, 1.71-10.04) of significant fibrosis compared HBsAg-negatives. Both significant fibrosis (adjusted hazard ratio 1.41, 95% CI, 1.21-1.64) and cirrhosis (adjusted hazard ratio 1.57, 95% CI, 1.31-1.89) were associated with increased all-cause mortality. CONCLUSION Liver fibrosis may be a risk factor for mortality during ART among HIV-infected individuals in Africa. APRI is an inexpensive and potentially useful test for liver fibrosis in resource-constrained settings. This article is protected by copyright. All rights reserved.

An Exploration Based Cognitive Bias Test for Mice: Effects of Handling Method and Stereotypic Behaviour

Behavioural tests to assess affective states are widely used in human research and have recently been extended to animals. These tests assume that affective state influences cognitive processing, and that animals in a negative affective state interpret ambiguous information as expecting a negative outcome (displaying a negative cognitive bias). Most of these tests however, require long discrimination training. The aim of the study was to validate an exploration based cognitive bias test, using two different handling methods, as previous studies have shown that standard tail handling of mice increases physiological and behavioural measures of anxiety compared to cupped handling. Therefore, we hypothesised that tail handled mice would display a negative cognitive bias. We handled 28 female CD-1 mice for 16 weeks using either tail handling or cupped handling. The mice were then trained in an eight arm radial maze, where two adjacent arms predicted a positive outcome (darkness and food), while the two opposite arms predicted a negative outcome (no food, white noise and light). After six days of training, the mice were also given access to the four previously unavailable intermediate ambiguous arms of the radial maze and tested for cognitive bias. We were unable to validate this test, as mice from both handling groups displayed a similar pattern of exploration. Furthermore, we examined whether maze exploration is affected by the expression of stereotypic behaviour in the home cage. Mice with higher levels of stereotypic behaviour spent more time in positive arms and avoided ambiguous arms, displaying a negative cognitive bias. While this test needs further validation, our results indicate that it may allow the assessment of affective state in mice with minimal training— a major confound in current cognitive bias paradigms.