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121.

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   
122.

Background

It is evident that professional driving is associated with substantial changes in lifestyle habits. Professional drivers are prone to metabolic syndrome (MetS) and its complications because their working environment is characterized by numerous stress factors such as lack of physical activity due to working in a fixed position, disruption in diet, and irregular sleep habits. The aim of the present study was to estimate the prevalence of MetS among long distance drivers residing in West Azerbaijan province in Iran.

Materials

To assess the prevalence of metabolic syndrome among professional long distance drivers, 12138 participants were enrolled in this cross sectional study. The MetS was defined using International Diabetes Federation criteria.

Results

Among12138 participants, 3697 subjects found to be MetS. The crude and age-adjusted rates of MetS were 30.5% and 32.4% respectively. Based on Body mass index (BMI), 5027 subjects (41.4%) were overweight (BMI ≥25.01–30 kg/m2), and 2592 (21.3%) were obese (BMI ≥30.01 kg/m2). The presence of central obesity was more common than other components. The associations of MetS with BMI, pack-year smoking, age, weekly driving duration and driving experiences were significant in the logistic regression. By increasing BMI, pack-year smoking, age, weekly driving duration and driving experiences, odds ratio of MetS was increased.

Conclusion

The study suggests that MetS has become a noteworthy health problem among Iranian long distance drivers. This might be due to the following facts: sitting in a fixed position for long hours while working, cigarette smoking, job stress, unhealthy diet and lack of physical activity. Educational programs should be established for promoting healthy lifestyle and also for early detection and appropriate interventions  相似文献   
123.
Helicobacter pylori is a Gram-negative spiral bacterium that colonizes human gastric mucosa causing infection. In this study aiming at inhibition of H. pylori infection we made an attempt to evaluate immunogenicity of the total (UreC) and C-terminal (UreCc) fragments of H. pylori urease. Total UreC and its C-terminal fragment were expressed in E. coli. Recombinant proteins were analyzed by SDS-PAGE and western blot and then purified by Ni-NTA affinity chromatography. Female C57BL6/j mice were immunized with the purified proteins (UreC and UreCc). Antibody titers from isolated sera were measured by ELISA. Immunized mice were then challenged by oral gavage with live H. pylori Sydney strain SS1. Total of 109 CFU were inoculated into stomach of immunized and unimmunized healthy mice three times each at one day interval. Eight weeks after the last inoculation, the blood sample was collected and the serum antibody titer was estimated by ELISA. Stomach tissues from control and experimental animal groups were studied histopathologically. UreC and UreCc yielded recombinant proteins of 61 and 31 kDa respectively. ELIZA confirmed establishment of immunity and the antibodies produced thereby efficiently recognized H. pylori and inhibited its colonization in vivo. Pathological analysis did not reveal established infection in immunized mice challenged with H. pylori. The results support the idea that UreC and UreCc specific antibodies contribute to protection against H. pylori infections.  相似文献   
124.
The objective of this study was to control the reproductive cycle of pikeperch (Sander lucioperca) through determining the effects of different photoperiods and handling stress on the reproduction quality, timing and quality of spawning, fertilization, sex steroids, and cortisol concentrations. In this study, 72 pikeperch broodstocks with an average weight of 1367 ± 55.3 g were exposed to different photoperiods including constant light (24L:0D), constant darkness (0L:24D), and 12 h of light, 12 h of darkness (12L:12D) for 40 days. Half of the broodstocks of each photoperiod treatment were exposed to handling stress at a specific time of the day. Applying different photoperiods caused changes in the timing of broodstocks' spawning, so that fish under 24L:0D spawned earlier than those of other photoperiods, and stressed fish of the 0L:24D photoperiod had a delayed spawning compared to others. Also, the spawning of the broodstocks at different photoperiods which were exposed to handling stress was either delayed or did not occur at all. The highest and lowest spawnings were observed in the morning and at night, respectively. Fertilization percentage, number of eggs per gram, sex steroids including estradiol, progesterone, and testosterone, as well as cortisol and calcium concentrations did not show any significant difference in different photoperiods and handling stress. In stressed males of the 24L:0D photoperiod, there only was a significant decrease of testosterone concentration compared to the beginning of the experiment. Results indicated that the spawning performance of pikeperch broodstocks could be considerably stimulated using an effective photoperiod. Similarly, pikeperch broodstocks in culture systems are usually affected by handling stress, and this stress could lead to a poor reproductive performance and inhibition of spawning.  相似文献   
125.
Glutathione S-transferases class zeta (GSTζ) is involved in the detoxification of xenobiotic compounds and catalyzes the biotransformation of a variety of α-haloacids including dichloroacetic acid and chlorofluoroacetic acid. It has been reported that, in mice, deficiency of Gstz1 (a member of GSTζ) resulted in the generation of a constant level of oxidative stress. The present study was carried out to investigate the association between genetic polymorphisms of GSTZ1 (in promoter site G-1002A and in coding sites Glu32Lys and Gly42Arg) and risk of breast cancer. We included 106 females with breast cancer and 106 healthy females frequency matched for age. The study polymorphisms were not associated with risk of breast cancer (p>0.05). The polymorphisms of GSTZ1 showed strong linkage disequilibrium among cancer patients and control subjects (p<0.0001). There was no significant difference between cancer patients and controls for frequencies of the GSTZ1 haplotypes (p>0.05). It seems there is no meaningful relationship between the genetic polymorphisms of GSTZ1 and risk of breast cancer.  相似文献   
126.
Preeclampsia (PE) is a complex disorder affected by genetic and environmental factors. Although the exact genes involved in development of PE are still not fully discovered, an important role for oxidative stress in its pathogenesis is accepted. In the present study, the association between the functional genetic polymorphisms in codons 32, 42 and nucleotide -1002 of glutathione S-transferases Z1 (GSTZ1) and susceptibility to PE was investigated. The present case-control study was performed on 151 preeclapmtic patients, and a total of 200 normal pregnant women, as a control group. The healthy control group was frequency matched with the age of the preeclamptic patients. Control subjects had no history of previous pregnancies with PE. Genotypes were determined by PCR-RFLP assay. There was no significant association between G-1002A and Glu32Lys polymorphisms of GSTZ1 with PE risk. The variant allele of Gly42Arg polymorphism decreased the risk of PE (OR = 0.24, 95 % CI 0.08-0.73, P = 0.012). The haplotype of "-1002A, 32Lys, 42Arg" (having three variant alleles) versus to the other haplotypes significantly decreased among PE patients compared to the control group (5.0 vs. 0.9 percent among control and PE patient groups, respectively; χ(2) = 9.328, df = 1, P = 0.002). The present results indicate that the haplotype of "-1002A, 32Lys, 42Arg" (containing three variant alleles) of GSTZ1 have protective effect compared to the other haplotypes.  相似文献   
127.
128.
MSCs (mesenchymal stem cells) have attracted attention as a promising tool for regenerative medicine and transplantation therapy. MSCs exert neuroprotective effects by secreting a number of factors in vitro and in vivo. Similar characteristics are found in ADSCs (adipose‐derived stem cells) and BMSCs (bone marrow stromal cells). Multipotent capability, easy accessibility and rapid proliferation of ADSCs have been established. Our main objective was to compare cell viability, growth rate, expression of neurotrophic factors and nestin genes in ADSCs and BMSCs. Cell doubling time and proliferation rate indicate that ADSCs has a higher proliferation rate than BMSCs. ADSCs and BMSCs express a similar pattern of CD71 and CD90 markers. Nestin immunostaining showed that ADSCs and BMSCs are immunopositive. The expression of neurotrophic factors genes in ADSCs proved similar to that of BMSCs genes. Thus adipose tissue stem cells with a high proliferation rate can express nestin and neurotrophic factor genes. Therefore ADSCs may be useful in future cell replacement therapies and help improve neurodegenerative diseases.  相似文献   
129.
Formation mechanism of laser-induced spontaneous periodic nanostructures in thin light-sensitive AgCl waveguide films, doped by silver nanoparticles, is studied. It is found that the initial size, geometry, and surface coverage parameters of Ag nanoparticles instate preconditions for the nanostructure formation. These parameters play essential roles in coupled nanoplasmon excitation in silver nanoclusters, which in turn influences scattering of the incident light from the silver clusters. Some parts of the scattered light propagate as waveguide modes in the film and interference with the incident light. Afterward, migration of the Ag nanoparticles into the minima of the interference pattern forms the nanostructure. Simultaneously, excitation of coupled nanoplasmons in the neighboring clusters enhances the scattered light intensity. It is observed that longer exposure results in destruction of the formed nanostructures, because of creation of electrical joint between agglomerated clusters in the interference pattern’s minima, which leads to weakening of the TE mode excitation and, consequently, domination of the Gaussian profile of the incident light. This leads to the deceleration of the self-organized nanostructure development, growth rate, and quality. We have found that competition between the Gaussian profile of the incident laser field and the interference field causes a finally saturating oscillatory behavior of the self-organizing process.  相似文献   
130.
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