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31.

Background

The impact of exposure to multiple pathogens concurrently or consecutively on immune function is unclear. Here, immune responses induced by combinations of the bacterium Salmonella Typhimurium (STm) and the helminth Nippostrongylus brasiliensis (Nb), which causes a murine hookworm infection and an experimental porin protein vaccine against STm, were examined.

Methodology/Principal Findings

Mice infected with both STm and Nb induced similar numbers of Th1 and Th2 lymphocytes compared with singly infected mice, as determined by flow cytometry, although lower levels of secreted Th2, but not Th1 cytokines were detected by ELISA after re-stimulation of splenocytes. Furthermore, the density of FoxP3+ T cells in the T zone of co-infected mice was lower compared to mice that only received Nb, but was greater than those that received STm. This reflected the intermediate levels of IL-10 detected from splenocytes. Co-infection compromised clearance of both pathogens, with worms still detectable in mice weeks after they were cleared in the control group. Despite altered control of bacterial and helminth colonization in co-infected mice, robust extrafollicular Th1 and Th2-reflecting immunoglobulin-switching profiles were detected, with IgG2a, IgG1 and IgE plasma cells all detected in parallel. Whilst extrafollicular antibody responses were maintained in the first weeks after co-infection, the GC response was less than that in mice infected with Nb only. Nb infection resulted in some abrogation of the longer-term development of anti-STm IgG responses. This suggested that prior Nb infection may modulate the induction of protective antibody responses to vaccination. To assess this we immunized mice with porins, which confer protection in an antibody-dependent manner, before challenging with STm. Mice that had resolved a Nb infection prior to immunization induced less anti-porin IgG and had compromised protection against infection.

Conclusion

These findings demonstrate that co-infection can radically alter the development of protective immunity during natural infection and in response to immunization.  相似文献   
32.

Background

Good adherence to antiretroviral therapy (ART) is critical for successful HIV treatment. However, some patients remain virologically suppressed despite suboptimal adherence. We hypothesized that this could result from host genetic factors influencing drug levels.

Methods

Eligible individuals were Caucasians treated with efavirenz (EFV) and/or boosted lopinavir (LPV/r) with self-reported poor adherence, defined as missing doses of ART at least weekly for more than 6 months. Participants were genotyped for single nucleotide polymorphisms (SNPs) in candidate genes previously reported to decrease EFV (rs3745274, rs35303484, rs35979566 in CYP2B6) and LPV/r clearance (rs4149056 in SLCO1B1, rs6945984 in CYP3A, rs717620 in ABCC2). Viral suppression was defined as having HIV-1 RNA <400 copies/ml throughout the study period.

Results

From January 2003 until May 2009, 37 individuals on EFV (28 suppressed and 9 not suppressed) and 69 on LPV/r (38 suppressed and 31 not suppressed) were eligible. The poor adherence period was a median of 32 weeks with 18.9% of EFV and 20.3% of LPV/r patients reporting missed doses on a daily basis. The tested SNPs were not determinant for viral suppression. Reporting missing >1 dose/week was associated with a lower probability of viral suppression compared to missing 1 dose/week (EFV: odds ratio (OR) 0.11, 95% confidence interval (CI): 0.01–0.99; LPV/r: OR 0.29, 95% CI: 0.09–0.94). In both groups, the probability of remaining suppressed increased with the duration of continuous suppression prior to the poor adherence period (EFV: OR 3.40, 95% CI: 0.62–18.75; LPV/r: OR 5.65, 95% CI: 1.82–17.56).

Conclusions

The investigated genetic variants did not play a significant role in the sustained viral suppression of individuals with suboptimal adherence. Risk of failure decreased with longer duration of viral suppression in this population.  相似文献   
33.
Reduced peripheral serotonin (5HT) in mice lacking tryptophan hydroxylase (TPH1), the rate limiting enzyme for 5HT synthesis, was reported to be anabolic to the skeleton. However, in other studies TPH1 deletion either had no bone effect or an age dependent inhibition of osteoclastic bone resorption. The role of 5HT in bone therefore remains poorly understood. To address this issue, we used selective breeding to create rat sublines with constitutively high (high-5HT) and low (low-5HT) platelet 5HT level (PSL) and platelet 5HT uptake (PSU). High-5HT rats had decreased bone volume due to increased bone turnover characterized by increased bone formation and mineral apposition rate, increased osteoclast number and serum C-telopeptide level. Daily oral administration of the TPH1 inhibitor (LX1032) for 6 weeks reduced PSL and increased the trabecular bone volume and trabecular number of the spine and femur in high-5HT rats. High-5HT animals also developed a type 2 diabetes (T2D) phenotype with increased: plasma insulin, glucose, hemoglobin A1c, body weight, visceral fat, β-cell pancreatic islets size, serum cholesterol, and decreased muscle strength. Serum calcium accretion mediated by parathyroid hormone slightly increased, whereas treatment with 1,25(OH)2D3 decreased PSL. Insulin reduction was paralleled by a drop in PSL in high-5HT rats. In vitro, insulin and 5HT synergistically up-regulated osteoblast differentiation isolated from high-5HT rats, whereas TPH1 inhibition decreased the number of bone marrow-derived osteoclasts. These results suggest that constitutively elevated PSL is associated with bone loss and T2D via a homeostatic interplay between the peripheral 5HT, bone and insulin.  相似文献   
34.
The biodegradation of undecylbenzenesulphonate (C11LAS) was studied in shake flasks at 21°C using two mixed bacterial cultures. The first culture, MM1, contained a type II methanotroph and four heterotrophs, and was enriched from a groundwater aquifer. The second culture, MC, consisted of five heterotrophic strains, most of them belonging to the genus Pseudomonas , and was isolated from the wastewater of a detergent plant. Methane, carbon dioxide and oxygen concentrations were determined by gas chromatography. Concentrations of C11LAS and the aromatic intermediates were determined by reversed-phase HPLC. In spite of faster transformation of the alkyl side-chain by the culture MC, the culture MM1 containing type II methanotroph was capable of further degradation of C11LAS aromatic intermediates (sulphophenylalkanoates). The most probable mechanism for the degradation of the alkyl part of the C11LAS molecule by both cultures was β-oxidation of the terminal methyl group followed by β-oxidation. Studies of methane utilization demonstrated an approximately three times higher second-order rate coefficient for methane consumption ( k max/ K s) in the absence of C11LAS. This indicates a possible metabolic activity of methanotrophs in the transformation of the complex LAS molecule due to the methane monooxygenase enzyme system.  相似文献   
35.

Purpose

Promoting the economic and environmental performance of Swiss farms is a major objective of Swiss agricultural policy. In the present paper, we investigate the relationship between the economic and global environmental performance of the Swiss dairy farms in the alpine area.

Methods

The analysis relies on a sample of 56 dairy farms from the Farm Accountancy Data Network, for which highly precise and comprehensive Life Cycle Assessments have been carried out. The work income per family work unit is used as indicator of the economic performance of a farm. The so-called global environmental performance of a farm is, for its part, measured by means of an eco-efficiency indicator for each environmental impact considered (demand for non-renewable energy resources, eutrophication potential, aquatic ecotoxicity potential, human toxicity potential and land use) and of an aggregate eco-efficiency indicator assessed using a Data Envelopment Analysis-based approach. The relationship between economic and global environmental performance is assessed by means of non-parametric Spearman??s rank correlation analysis.

Results

The results of the analysis reveal the existence of a positive relationship between economic and global environmental performance. This positive relationship exists for all environmental issues considered and thus also for the aggregate eco-efficiency indicator. Its strength, however, substantially varies from one issue to another.

Conclusions

This study provides the evidence that there is no trade-off between economic and global environmental farm performance. When they improve their economic performance, farms also tend to improve their global environmental performance and vice versa. This finding is of central relevance for policy-makers as it should contribute to improving the acceptance among farmers of the environmental objectives of Swiss agricultural policy in terms of an increase in environmental resource use productivity. In this sense this work provides valuable insights into the sustainable performance of the Swiss dairy sector in the alpine area.  相似文献   
36.
37.
How does asexual reproduction influence genome evolution? Although is it clear that genomic structural variation is common and important in natural populations, we know very little about how one of the most fundamental of eukaryotic traits—mode of genomic inheritance—influences genome structure. We address this question with the New Zealand freshwater snail Potamopyrgus antipodarum, which features multiple separately derived obligately asexual lineages that coexist and compete with otherwise similar sexual lineages. We used whole-genome sequencing reads from a diverse set of sexual and asexual individuals to analyze genomic abundance of a critically important gene family, rDNA (the genes encoding rRNAs), that is notable for dynamic and variable copy number. Our genomic survey of rDNA in P. antipodarum revealed two striking results. First, the core histone and 5S rRNA genes occur between tandem copies of the 18S–5.8S–28S gene cluster, a unique architecture for these crucial gene families. Second, asexual P. antipodarum harbor dramatically more rDNA–histone copies than sexuals, which we validated through molecular and cytogenetic analysis. The repeated expansion of this genomic region in asexual P. antipodarum lineages following distinct transitions to asexuality represents a dramatic genome structural change associated with asexual reproduction—with potential functional consequences related to the loss of sexual reproduction.  相似文献   
38.
Eating disorders in early childhood are the same frequency in boys and girls. During adolescence eating disorders are ten (10) times more frequent in girls than in boys. Worrying is the fact that eating disorders are the third chronic illness among adolescents after obesity and asthma. Depicting this adolescent we tried to show difficulty of treatment of this disorder, where in the beginning is important to stabilize body weight and prevent somatic damages such as: heart damage, amenorrhoea, changes in EKG (electrocardiogram) and electrolyte dysbalance that could endanger the life of patient. Simultaneously it is important to recognize and treat comorbid psychological disturbances such as in this case: depression, delusions with occasional psychotic reactions combined with unrealistic thinking about the layout of her own body. There is still no cure for the treatment of eating disorders which are in growing number of reports among male adolescents.  相似文献   
39.
The aim of the study was investigation of specific forensic aspects in offenders involved in domestic homicide cases in regard to sociodemographic and psychosocial variables and modalities of the offense. The research was conducted at the Department of Forensic Psychiatry in Neuropsychiatric Hospital "Dr. Ivan Barbot" in Popovaca, Croatia. The sample in this study consisted of domestic homicide group (N = 162). The results showed certain characteristics within the group of domestic homicide offenders. Generally speaking the offenders in domestic homicide cases were often married and were living in their families. Moreover, they were brought up in families with both parents and they had history of regular military service. Furthermore, offenders in domestic homicide cases were less involved in intervention from social services with rare history of home runaway and substance abuse during adolescence. Finally, the same group of offenders was less often had mothers or close friends with antisocial personality disorder but had frequent language and speech problems during adolescent period. In regard to the victims of domestic homicide they were often aged females. The offenders usually commit crime in their living space, either in the house or in the apartment. Based on these findings we conclude there are certain specific characteristics in the domestic homicide cases compared to homicide in general.  相似文献   
40.
Vasopressin (AVP) receptors present in In-R1-G9 cells, a hamster glucagon-secreting alpha-pancreatic cell line, were characterized using SSR-149415, a selective nonpeptide V1b receptor antagonist, and reference AVP compounds. Binding experiments, using [3H]AVP as a ligand, identified a single population of high-affinity binding sites. SSR-149415 competitively inhibited this binding and exhibited nanomolar and stereospecific affinity for these sites. The affinity of various AVP/oxytocin ligands confirmed a V1b binding profile. In functional studies, AVP was a potent stimulant in inducing intracellular Ca2+ increase, glucagon secretion, and cell proliferation. These effects were fully antagonized by SSR-149415 with a nanomolar potency, whereas its diasteroisomer as well as two selective V1a and V2 receptor antagonists were much less potent. Additionally, the order of potency of AVP agonists and antagonists was in agreement with V1b-mediated effects. By RT-PCR, we confirmed the presence of V1b receptor mRNA in both In-R1-G9 cells and in human pancreas. The distribution pattern of V1b receptors investigated in human pancreas by immunohistochemistry showed strong labeling in islets of Langerhans, and colocalization studies indicated that this receptor was expressed in alpha-glucagon, beta-insulin, and somatostatin pancreatic cells. Thus, in In-R1-G9 cells, AVP mediates intracellular Ca2+ increase, glucagon secretion, and cell proliferation by activating V1b receptors, and these effects are potently antagonized by SSR-149415. Moreover, the presence of V1b receptors also found in human Langerhans islets could suggest hormonal control of AVP in human pancreas.  相似文献   
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