196 research outputs found

    TBR2-immunopsitive unipolar brush cells are associated with ectopic zebrin II-immunoreactive Purkinje cell clusters in the cerebellum of scrambler mice

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    Unipolar brush cells (UBCs) are excitatory interneurons with their somata located in the granular layer. Recently, T-brain factor 2 (Tbr2) was shown to be expressed in a subset of UBCs in mouse cerebellum. Scrambler mice exhibit severe cerebellum abnormalities, including the failure of embryonic Purkinje cell dispersal and a complete absence of foliation due to a mutation in the disabled-1 adaptor protein. Since most UBC markers are expressed postnatally, it has proven difficult to identify the relationship between developing Purkinje cell clusters and migrating UBCs. Because scrambler mice closely mimic normal embryonic day 18 cerebellum, we examined whether Tbr2-positive UBCs are associated with Purkinje cell cluster markers such as zebrin II, which is the most studied compartmentation marker in the cerebellum. We investigated the distribution of Tbr2-positive UBCs in this mutant by using anti-Tbr2 immunocytochemistry. The data revealed that Tbr2 immunoreactivity was exclusively present in the nucleus of UBCs in scrambler cerebellum. Based on expression data, a Tbr2-positive UBC map was constructed. In addition, Tbr2-positive UBCs are found associated with ectopic zebrin II-immunoreactive Purkinje cell clusters in scrambler cerebellum. These data suggest that UBCs use Purkinje cell compartmentation to migrate into their final position through interactions with the embryonic array of specific Purkinje cell subtypes

    Influence of Obesity on Bone Mineral Density in Postmenopausal Asthma Patients Undergoing Treatment with Inhaled Corticosteroids

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    OBJECTIVES: The etiology of osteoporosis in asthma is complex as various factors contribute to its pathogenesis. The purpose of our study was to investigate the effects of obesity and inhaled steroids, as well as the severity and duration of asthma, on osteoporosis in postmenopausal asthma patients as compared to healthy controls. METHODS: A total of 46 patients with asthma and 60 healthy female controls, all postmenopausal, were enrolled in our study. Bone mineral density was assessed at the lumbar spine and hip using a Lunar DPX-L densitometer. RESULTS: Bone mineral density (BMD) scores were comparable between the asthmatic and control groups, with average scores of 0.95 ± 0.29 and 0.88 ± 0.14 g/cm², respectively. Likewise, osteoporosis was diagnosed in a similar percentage of patients in the asthmatic (39.1%) and control (43.3%) groups. Bone fracture was identified in four patients with asthma (8.6%) and in six patients from the control group (10%). We could not detect any relationship between BMD and duration of asthma, asthma severity, inhaled steroids or body mass index (BMI). There was no difference between the two groups with respect to age or years since menopause. Although asthma patients were more likely to be overweight and presented higher BMD scores on average than the control subjects, these differences were not statistically significant. CONCLUSIONS: There is a slight positive protective effect of high BMI against osteoporosis in asthma patients, but this effect is overcome by time and menopause status. Therefore, the protective effect of obesity against osteoporosis in asthma patients seems to not be significant

    Inhaled steroids and risk of pneumonia for chronic obstructive pulmonary disease.

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    BACKGROUND: Inhaled corticosteroids (ICS) are anti-inflammatory drugs that have proven benefits for people with worsening symptoms of chronic obstructive pulmonary disease (COPD) and repeated exacerbations. They are commonly used as combination inhalers with long-acting beta2-agonists (LABA) to reduce exacerbation rates and all-cause mortality, and to improve lung function and quality of life. The most common combinations of ICS and LABA used in combination inhalers are fluticasone and salmeterol, budesonide and formoterol and a new formulation of fluticasone in combination with vilanterol, which is now available. ICS have been associated with increased risk of pneumonia, but the magnitude of risk and how this compares with different ICS remain unclear. Recent reviews conducted to address their safety have not compared the relative safety of these two drugs when used alone or in combination with LABA. OBJECTIVES: To assess the risk of pneumonia associated with the use of fluticasone and budesonide for COPD. SEARCH METHODS: We identified trials from the Cochrane Airways Group Specialised Register of trials (CAGR), clinicaltrials.gov, reference lists of existing systematic reviews and manufacturer websites. The most recent searches were conducted in September 2013. SELECTION CRITERIA: We included parallel-group randomised controlled trials (RCTs) of at least 12 weeks' duration. Studies were included if they compared the ICS budesonide or fluticasone versus placebo, or either ICS in combination with a LABA versus the same LABA as monotherapy for people with COPD. DATA COLLECTION AND ANALYSIS: Two review authors independently extracted study characteristics, numerical data and risk of bias information for each included study.We looked at direct comparisons of ICS versus placebo separately from comparisons of ICS/LABA versus LABA for all outcomes, and we combined these with subgroups when no important heterogeneity was noted. After assessing for transitivity, we conducted an indirect comparison to compare budesonide versus fluticasone monotherapy, but we could not do the same for the combination therapies because of systematic differences between the budesonide and fluticasone combination data sets.When appropriate, we explored the effects of ICS dose, duration of ICS therapy and baseline severity on the primary outcome. Findings of all outcomes are presented in 'Summary of findings' tables using GRADEPro. MAIN RESULTS: We found 43 studies that met the inclusion criteria, and more evidence was provided for fluticasone (26 studies; n = 21,247) than for budesonide (17 studies; n = 10,150). Evidence from the budesonide studies was more inconsistent and less precise, and the studies were shorter. The populations within studies were more often male with a mean age of around 63, mean pack-years smoked over 40 and mean predicted forced expiratory volume of one second (FEV1) less than 50%.High or uneven dropout was considered a high risk of bias in almost 40% of the trials, but conclusions for the primary outcome did not change when the trials at high risk of bias were removed in a sensitivity analysis.Fluticasone increased non-fatal serious adverse pneumonia events (requiring hospital admission) (odds ratio (OR) 1.78, 95% confidence interval (CI) 1.50 to 2.12; 18 more per 1000 treated over 18 months; high quality), and no evidence suggested that this outcome was reduced by delivering it in combination with salmeterol or vilanterol (subgroup differences: I(2) = 0%, P value 0.51), or that different doses, trial duration or baseline severity significantly affected the estimate. Budesonide also increased non-fatal serious adverse pneumonia events compared with placebo, but the effect was less precise and was based on shorter trials (OR 1.62, 95% CI 1.00 to 2.62; six more per 1000 treated over nine months; moderate quality). Some of the variation in the budesonide data could be explained by a significant difference between the two commonly used doses: 640 mcg was associated with a larger effect than 320 mcg relative to placebo (subgroup differences: I(2) = 74%, P value 0.05).An indirect comparison of budesonide versus fluticasone monotherapy revealed no significant differences with respect to serious adverse events (pneumonia-related or all-cause) or mortality. The risk of any pneumonia event (i.e. less serious cases treated in the community) was higher with fluticasone than with budesonide (OR 1.86, 95% CI 1.04 to 3.34); this was the only significant difference reported between the two drugs. However, this finding should be interpreted with caution because of possible differences in the assignment of pneumonia diagnosis, and because no trials directly compared the two drugs.No significant difference in overall mortality rates was observed between either of the inhaled steroids and the control interventions (both high-quality evidence), and pneumonia-related deaths were too rare to permit conclusions to be drawn. AUTHORS' CONCLUSIONS: Budesonide and fluticasone, delivered alone or in combination with a LABA, are associated with increased risk of serious adverse pneumonia events, but neither significantly affected mortality compared with controls. The safety concerns highlighted in this review should be balanced with recent cohort data and established randomised evidence of efficacy regarding exacerbations and quality of life. Comparison of the two drugs revealed no statistically significant difference in serious pneumonias, mortality or serious adverse events. Fluticasone was associated with higher risk of any pneumonia when compared with budesonide (i.e. less serious cases dealt with in the community), but variation in the definitions used by the respective manufacturers is a potential confounding factor in their comparison.Primary research should accurately measure pneumonia outcomes and should clarify both the definition and the method of diagnosis used, especially for new formulations such as fluticasone furoate, for which little evidence of the associated pneumonia risk is currently available. Similarly, systematic reviews and cohorts should address the reliability of assigning 'pneumonia' as an adverse event or cause of death and should determine how this affects the applicability of findings

    Long-acting inhaled therapy (beta-agonists, anticholinergics and steroids) for COPD: a network meta-analysis.

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    BACKGROUND: Pharmacological therapy for chronic obstructive pulmonary disease (COPD) is aimed at relieving symptoms, improving quality of life and preventing or treating exacerbations.Treatment tends to begin with one inhaler, and additional therapies are introduced as necessary. For persistent or worsening symptoms, long-acting inhaled therapies taken once or twice daily are preferred over short-acting inhalers. Several Cochrane reviews have looked at the risks and benefits of specific long-acting inhaled therapies compared with placebo or other treatments. However for patients and clinicians, it is important to understand the merits of these treatments relative to each other, and whether a particular class of inhaled therapies is more beneficial than the others. OBJECTIVES: To assess the efficacy of treatment options for patients whose chronic obstructive pulmonary disease cannot be controlled by short-acting therapies alone. The review will not look at combination therapies usually considered later in the course of the disease.As part of this network meta-analysis, we will address the following issues.1. How does long-term efficacy compare between different pharmacological treatments for COPD?2. Are there limitations in the current evidence base that may compromise the conclusions drawn by this network meta-analysis? If so, what are the implications for future research? SEARCH METHODS: We identified randomised controlled trials (RCTs) in existing Cochrane reviews by searching the Cochrane Database of Systematic Reviews (CDSR). In addition, we ran a comprehensive citation search on the Cochrane Airways Group Register of trials (CAGR) and checked manufacturer websites and reference lists of other reviews. The most recent searches were conducted in September 2013. SELECTION CRITERIA: We included parallel-group RCTs of at least 6 months' duration recruiting people with COPD. Studies were included if they compared any of the following treatments versus any other: long-acting beta2-agonists (LABAs; formoterol, indacaterol, salmeterol); long-acting muscarinic antagonists (LAMAs; aclidinium, glycopyrronium, tiotropium); inhaled corticosteroids (ICSs; budesonide, fluticasone, mometasone); combination long-acting beta2-agonist (LABA) and inhaled corticosteroid (LABA/ICS) (formoterol/budesonide, formoterol/mometasone, salmeterol/fluticasone); and placebo. DATA COLLECTION AND ANALYSIS: We conducted a network meta-analysis using Markov chain Monte Carlo methods for two efficacy outcomes: St George's Respiratory Questionnaire (SGRQ) total score and trough forced expiratory volume in one second (FEV1). We modelled the relative effectiveness of any two treatments as a function of each treatment relative to the reference treatment (placebo). We assumed that treatment effects were similar within treatment classes (LAMA, LABA, ICS, LABA/ICS). We present estimates of class effects, variability between treatments within each class and individual treatment effects compared with every other.To justify the analyses, we assessed the trials for clinical and methodological transitivity across comparisons. We tested the robustness of our analyses by performing sensitivity analyses for lack of blinding and by considering six- and 12-month data separately. MAIN RESULTS: We identified 71 RCTs randomly assigning 73,062 people with COPD to 184 treatment arms of interest. Trials were similar with regards to methodology, inclusion and exclusion criteria and key baseline characteristics. Participants were more often male, aged in their mid sixties, with FEV1 predicted normal between 40% and 50% and with substantial smoking histories (40+ pack-years). The risk of bias was generally low, although missing information made it hard to judge risk of selection bias and selective outcome reporting. Fixed effects were used for SGRQ analyses, and random effects for Trough FEV1 analyses, based on model fit statistics and deviance information criteria (DIC). SGRQ SGRQ data were available in 42 studies (n = 54,613). At six months, 39 pairwise comparisons were made between 18 treatments in 25 studies (n = 27,024). Combination LABA/ICS was the highest ranked intervention, with a mean improvement over placebo of -3.89 units at six months (95% credible interval (CrI) -4.70 to -2.97) and -3.60 at 12 months (95% CrI -4.63 to -2.34). LAMAs and LABAs were ranked second and third at six months, with mean differences of -2.63 (95% CrI -3.53 to -1.97) and -2.29 (95% CrI -3.18 to -1.53), respectively. Inhaled corticosteroids were ranked fourth (MD -2.00, 95% CrI -3.06 to -0.87). Class differences between LABA, LAMA and ICS were less prominent at 12 months. Indacaterol and aclidinium were ranked somewhat higher than other members of their classes, and formoterol 12 mcg, budesonide 400 mcg and formoterol/mometasone combination were ranked lower within their classes. There was considerable overlap in credible intervals and rankings for both classes and individual treatments. Trough FEV1 Trough FEV1 data were available in 46 studies (n = 47,409). At six months, 41 pairwise comparisons were made between 20 treatments in 31 studies (n = 29,271). As for SGRQ, combination LABA/ICS was the highest ranked class, with a mean improvement over placebo of 133.3 mL at six months (95% CrI 100.6 to 164.0) and slightly less at 12 months (mean difference (MD) 100, 95% CrI 55.5 to 140.1). LAMAs (MD 103.5, 95% CrI 81.8 to 124.9) and LABAs (MD 99.4, 95% CrI 72.0 to 127.8) showed roughly equivalent results at six months, and ICSs were the fourth ranked class (MD 65.4, 95% CrI 33.1 to 96.9). As with SGRQ, initial differences between classes were not so prominent at 12 months. Indacaterol and salmeterol/fluticasone were ranked slightly better than others in their class, and formoterol 12, aclidinium, budesonide and formoterol/budesonide combination were ranked lower within their classes. All credible intervals for individual rankings were wide. AUTHORS' CONCLUSIONS: This network meta-analysis compares four different classes of long-acting inhalers for people with COPD who need more than short-acting bronchodilators. Quality of life and lung function were improved most on combination inhalers (LABA and ICS) and least on ICS alone at 6 and at 12 months. Overall LAMA and LABA inhalers had similar effects, particularly at 12 months. The network has demonstrated the benefit of ICS when added to LABA for these outcomes in participants who largely had an FEV1 that was less than 50% predicted, but the additional expense of combination inhalers and any potential for increased adverse events (which has been established by other reviews) require consideration. Our findings are in keeping with current National Institute for Health and Care Excellence (NICE) guidelines

    X-linked Angelman-like syndrome caused by Slc9a6 knockout in mice exhibits evidence of endosomal–lysosomal dysfunction

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    Mutations in solute carrier family 9 isoform 6 on chromosome Xq26.3 encoding sodium–hydrogen exchanger 6, a protein mainly expressed in early and recycling endosomes are known to cause a complex and slowly progressive degenerative human neurological disease. Three resulting phenotypes have so far been reported: an X-linked Angelman syndrome-like condition, Christianson syndrome and corticobasal degeneration with tau deposition, with each characterized by severe intellectual disability, epilepsy, autistic behaviour and ataxia. Hypothesizing that a sodium–hydrogen exchanger 6 deficiency would most likely disrupt the endosomal–lysosomal system of neurons, we examined Slc9a6 knockout mice with tissue staining and related techniques commonly used to study lysosomal storage disorders. As a result, we found that sodium–hydrogen exchanger 6 depletion leads to abnormal accumulation of GM2 ganglioside and unesterified cholesterol within late endosomes and lysosomes of neurons in selective brain regions, most notably the basolateral nuclei of the amygdala, the CA3 and CA4 regions and dentate gyrus of the hippocampus and some areas of cerebral cortex. In these select neuronal populations, histochemical staining for β-hexosaminidase activity, a lysosomal enzyme involved in the degradation of GM2 ganglioside, was undetectable. Neuroaxonal dystrophy similar to that observed in lysosomal disease was observed in the cerebellum and was accompanied by a marked and progressive loss of Purkinje cells, particularly in those lacking the expression of Zebrin II. On behavioural testing, Slc9a6 knockout mice displayed a discrete clinical phenotype attributable to motor hyperactivity and cerebellar dysfunction. Importantly, these findings show that sodium–hydrogen exchanger 6 loss of function in the Slc9a6-targeted mouse model leads to compromise of endosomal–lysosomal function similar to lysosomal disease and to conspicuous neuronal abnormalities in specific brain regions, which in concert could provide a unified explanation for the cellular and clinical phenotypes in humans with SLC9A6 mutations

    The Reelin Receptors Apoer2 and Vldlr Coordinate the Patterning of Purkinje Cell Topography in the Developing Mouse Cerebellum

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    The adult cerebellar cortex is comprised of reproducible arrays of transverse zones and parasagittal stripes of Purkinje cells. Adult stripes are created through the perinatal rostrocaudal dispersion of embryonic Purkinje cell clusters, triggered by signaling through the Reelin pathway. Reelin is secreted by neurons in the external granular layer and deep cerebellar nuclei and binds to two high affinity extracellular receptors on Purkinje cells-the Very low density lipoprotein receptor (Vldlr) and apolipoprotein E receptor 2 (Apoer2). In mice null for either Reelin or double null for Vldlr and Apoer2, Purkinje cell clusters fail to disperse. Here we report that animals null for either Vldlr or Apoer2 individually, exhibit specific and parasagittally-restricted Purkinje cell ectopias. For example, in mice lacking Apoer2 function immunostaining reveals ectopic Purkinje cells that are largely restricted to the zebrin II-immunonegative population of the anterior vermis. In contrast, mice null for Vldlr have a much larger population of ectopic Purkinje cells that includes members from both the zebrin II-immunonegative and -immunopositive phenotypes. HSP25 immunoreactivity reveals that in Vldlr null animals a large portion of zebrin II-immunopositive ectopic cells are probably destined to become stripes in the central zone (lobules VI–VII). A small population of ectopic zebrin II-immunonegative Purkinje cells is also observed in animals heterozygous for both receptors (Apoer2+/−: Vldlr+/−), but no ectopia is present in mice heterozygous for either receptor alone. These results indicate that Apoer2 and Vldlr coordinate the dispersal of distinct, but overlapping subsets of Purkinje cells in the developing cerebellum

    A phase II clinical trial of 6-mercaptopurine (6MP) and methotrexate in patients with BRCA defective tumours:a study protocol

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    BACKGROUND: BRCA1 and BRCA2 genes are critical in homologous recombination DNA repair and have been implicated in familial breast and ovarian cancer tumorigenesis. Tumour cells with these mutations demonstrate increased sensitivity to cisplatin and poly (ADP-ribose) polymerase (PARP) inhibitors. 6MP was identified in a screen for novel drugs and found to selectively kill BRCA-defective cells in a xenograft model as effectively as the PARP inhibitor AGO14699, even after these cells had acquired resistance to a PARP inhibitor or cisplatin. Exploiting the genetic basis of these tumours enables us to develop a more tailored approach to therapy for patients with BRCA mutated cancers. METHODS: This multi-centre phase II single arm trial was designed to investigate the activity and safety of 6-mercaptopurine (6MP) 55 mg/m² per day, and methotrexate 15 mg/m² per week in patients with advanced breast or ovarian cancer, ECOG PS 0-2, progressing after ≥ one prior regimen and known to bear a BRCA1/2 germ line mutation. Accrual was planned in two stages, with treatment continuing until progression or unacceptable toxicity; in the first, if less than 3/30 evaluable patients respond at 8 weeks after commencing treatment, the trial will be stopped for futility; if not, then accrual would proceed to a second stage, in which if more than 9/65 evaluable patients are found to respond at 8 weeks, the treatment will be regarded as potentially effective and a phase III trial considered subject to satisfactory safety and tolerability. The primary outcome is objective response at 8 weeks, defined by RECISTS v1.1 as complete response, partial response or stable disease. Secondary outcomes include safety, progression- free and overall survival, and quality of life. DISCUSSION: This study aims to investigate whether 6MP might be an effective treatment for BRCA deficient tumours even after the development of resistance to PARP inhibitors or platinum drugs. The study has surpassed the first stage analysis criteria of more than 3 out of 30 evaluable patients responding at 8 weeks, and is currently in the second stage of recruitment. TRIAL REGISTRATION: NCT01432145 http://www.ClinicalTrials.gov
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