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71.

Background

The pathogenesis of COPD is complex and remains poorly understood. The European Respiratory Society Study on Chronic Obstructive Pulmonary Disease (EUROSCOP) investigated long-term effects of budesonide; 18% of the COPD participants were atopic. So far effects of atopy on the long-term course of COPD have not been elucidated.

Methods

Factors related to the presence of atopy (positive phadiatop) in 1277 mild-to-moderate COPD patients participating in EUROSCOP were analysed using regression analysis. Incidence and remission of respiratory symptoms during 3-year follow-up were analysed using generalised estimating equations models, and association of atopy with lung function decline using linear mixed effects models.

Results

Independent predisposing factors associated with the presence of atopy were: male gender (OR: 2.21; 95% CI: 1.47–3.34), overweight/obese (OR: 1.41; 95% CI: 1.04–1.92) and lower age (OR: 0.98; 95% CI: 0.96–0.99). Atopy was associated with a higher prevalence of cough (OR: 1.71; 95% CI: 1.26–2.34) and phlegm (OR: 1.50; 95% CI: 1.10–2.03), but not with lung function levels or FEV1 decline. Atopic COPD patients not treated with budesonide had an increased incidence of cough over time (OR: 1.79, 95% CI: 1.03–3.08, p = 0.038), while those treated with budesonide had increased remission of cough (OR: 1.93, 95% CI: 1.11–3.37, p = 0.02) compared to non-atopic COPD patients.

Conclusions

Atopic COPD patients are more likely male, have overweight/obesity and are younger as compared with non-atopic COPD patients. Atopy in COPD is associated with an increased incidence and prevalence of respiratory symptoms. If atopic COPD patients are treated with budesonide, they more often show remission of symptoms compared to non-atopic COPD patients who are treated with budesonide. We recommend including atopy in the diagnostic work-up and management of COPD.  相似文献   
72.

Background

Alveolar echinococcosis is a zoonotic disease caused by the metacestode of Echinococcus multilocularis. Many species of small mammals, including arvicolid rodents or Ochotona spp., are natural intermediate hosts of the cestode. The main aim of this study was to identify natural intermediate hosts of E. multilocularis in Chenaran County, Razavi Khorasan Province, northeastern Iran, where the prevalence of infected wild and domestic carnivores is high.

Methodology/Principal Findings

A program of trapping was carried out in five villages in which this cestode was reported in carnivores. The livers of 85 small mammals were investigated for the presence of E. multilocularis infection using multiplex PCR of mitochondrial genes. Infections were identified in 30 specimens: 23 Microtus transcaspicus, three Ochotona rufescens, two Mus musculus, one Crocidura gmelini, and one Apodemus witherbyi.

Conclusions/Significance

A range of small mammals therefore act as natural intermediate hosts for the transmission of E. multilocularis in Chenaran County, and the prevalence suggested that E. multilocularis infection is endemic in this region. The existence of the life cycle of this potentially lethal cestode in the vicinity of human habitats provides a significant risk of human infection.  相似文献   
73.

Background

Echinococcus multilocularis is the source of alveolar echinococcosis, a potentially fatal zoonotic disease. This investigation assessed the presence of E. multilocularis infection in definitive hosts in the Chenaran region of Razavi Khorasan Province, northeastern Iran.

Methodology/Principal Findings

Fecal samples from 77 domestic and stray dogs and 14 wild carnivores were examined using the flotation/sieving method followed by multiplex PCR of mitochondrial genes. The intestinal scraping technique (IST) and the sedimentation and counting technique (SCT) revealed adult Echinococcus in the intestines of five of 10 jackals and of the single wolf examined. Three jackals were infected only with E. multilocularis but two, and the wolf, were infected with both E. multilocularis and E. granulosus. Multiplex PCR revealed E. multilocularis, E. granulosus, and Taenia spp. in 19, 24, and 28 fecal samples, respectively. Echinococcus multilocularis infection was detected in the feces of all wild carnivores sampled including nine jackals, three foxes, one wolf, one hyena, and five dogs (6.5%). Echinococcus granulosus was found in the fecal samples of 16.9% of dogs, 66.7% of jackals, and all of the foxes, the wolf, and the hyena. The feces of 16 (21.8%) dogs, 7 of 9 (77.8%) jackals, and all three foxes, one wolf and one hyena were infected with Taenia spp.

Conclusions/Significance

The prevalence of E. multilocularis in wild carnivores of rural areas of the Chenaran region is high, indicating that the life cycle is being maintained in northeastern Iran with the red fox, jackal, wolf, hyena, and dog as definitive hosts.  相似文献   
74.
75.
Loop-mediated isothermal amplification (LAMP) is a promising nucleic acid assay for rapid and cost-effective detection of pathogen-specific sequences within a sample. Development of an appropriate taxonomic group-specific LAMP assay highly relies on the design of proper primers to cover all major members of the taxon. Regarding this fact, we designed and evaluated a new LAMP primer set specific to prt (rfbS) gene for rapid identification of Salmonella serogroup D serotypes. Unlike the previously reported LAMP assay for serogroup D which detects solely the non-typhoidal serotypes; the new LAMP primers set detects both typhoidal and non-typhoidal serotypes of this serogroup with a detection limit of 10 CFU/rection. Furthermore, the technique was successfully applied to artificially contaminated meat samples with an inoculation level of 1–5 CFU/250 ml of Salmonella Enteritidis, following a 5-h pre-enrichment step in tryptic soy broth. Overall, the new LAMP assay and its optimized setup would be useful for fast diagnosis of food poisoning incidents caused by these bacteria.  相似文献   
76.
New amphiphilic chitosan derivatives of all trans retinoic acid-chitosan (RA-chitosan) with different molar feeding ratios of all trans retinoic acid (ATRA) were synthesized. The degree of ATRA substitution ranged from 8.72% to 18.78%. The RA-chitosan formed micelles with an average size of 142.14-208.4 nm, and zeta potential of +27.25 to 34.48 mV. The critical association concentration (CAC) was found to range from 1.3 × 10−2 to 2.13 × 10−2 mg ml−1. Upon evaluation, the RA-chitosan shows no significant cytotoxicity on Hela and HepG2 cells. Analysis of micelles loaded with ATRA revealed that the size of micelles decreased by increasing loaded drug content while zeta potential did not change. ATRA was released slowly over 3-day period, and drug content had no effect on the release rate. These phenomena make RA-chitosan micelles as a candidate for drug carrier.  相似文献   
77.
Diabetes in pregnancy impairs hippocampus development in offspring, leading to behavioral problems and learning deficits. Phosphatidylinositol 3-kinase/protein kinase B (PKB/Akt) signaling pathway plays a pivotal role in the regulation of neuronal proliferation, survival and death. The present study was designed to examine the effects of maternal diabetes on PKB/Akt expression and phosphorylation in the developing rat hippocampus. Wistar female rats were maintained diabetic from a week before pregnancy through parturition and male offspring was killed at first postnatal day (P1). The hippocampal expression and phosphorylation level of PKB/Akt, one of the key molecules in PI3K/AKT signaling pathway, was evaluated using real-time polymerase chain reaction (PCR) and western blot analysis. We found a significant bilateral downregulation of AKT1 gene expression in the hippocampus of pups born to diabetic mothers (p?<?0.05). Interestingly, our results revealed a marked upregulation of Akt1 gene in insulin-treated group compared with other groups (p?<?0.05). The western blot analysis also showed the reduction of phosphorylation level of all AKT isoforms in both diabetic and insulin-treated groups compared with control (p?<?0.05). Moreover, the results showed a significant increase in phosphorylation level of AKT in insulin-treated group compared with the diabetic group. These results represent that diabetes during pregnancy strongly influences the regulation of PKB/AKT in the developing rat hippocampus. Furthermore, although the control of glycemia by insulin administration is not sufficient to prevent the alterations in PKB/Akt expression, it modulates the phosphorylation process, thus ultimately resulting in a situation comparable to that found in the normal condition.  相似文献   
78.
It is well established that Foxo3a is a fundamental module of signal transduction pathways regulating erythropoiesis; however, precise mechanism which regulates its physiological function still remains unclear. Here, our results revealed that the nuclear localization and stability of Foxo3a were modulated by the physical interaction of PKC and p38 signaling elements and that direct interactions led to phosphorylation of threonine residue(s) in Foxo3a. In addition, our findings revealed that the sequential activity of Foxo3a by guanosine 5′-triphosphate can impede cellular proliferation and suppress p73 expression as oncoprotein in K562 cells; thus identifying Foxo3a as a tumor suppressor in these p53 null cells. However, down-regulation of Foxo3a-dependent p73 expression causes cell differentiation along the erythroid lineage. Collectively, our findings suggest that restoration of Foxo3a function by pharmacological agents under the influence of specific activated protein kinases might constitute a potential therapeutic strategy for combating the CML disease.  相似文献   
79.
The Wnt pathway is the most important cascade in the nervous system; evidence has indicated that deregulation of the Wnt pathway induced pathogenic hallmarks of neurodegenerative diseases. Glycogen synthase kinase-3β (GSK-3β) as the main member of the Wnt pathway increases tau inclusions, the main marker in the neurodegenerative diseases. Phosphorylated tau is observed in the pre-tangle of the neurons in the early stage of neurodegenerative diseases. The researchers always try to improve pharmacological approaches of new therapeutic strategies to the treatment of neurodegenerative diseases that are required to represent a significant entry point by understanding the theoretical interactions of the molecular pathways. In this review, we have discussed the recent knowledge about the canonical and non-canonical Wnt signalling pathway, GSK-3β, Wnt/β-catenin antagonists, tau phosphorylation, and their important roles in the neurodegenerative diseases.  相似文献   
80.
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