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81.
The bacterium Pseudomonas aeruginosa causes chronic respiratory infections in cystic fibrosis (CF) patients. Such infections are extremely difficult to control because the bacteria exhibit a biofilm-mode of growth, rendering P. aeruginosa resistant to antibiotics and phagocytic cells. During the course of infection, P. aeruginosa usually undergoes a phenotypic switch to a mucoid colony, which is characterized by the overproduction of the exopolysaccharide alginate. Alginate overproduction has been implicated in protecting P. aeruginosa from the harsh environment present in the CF lung, as well as facilitating its persistence as a biofilm by providing an extracellular matrix that promotes adherence. Because of its association with biofilms in CF patients, it has been assumed that alginate is also the primary exopolysaccharide expressed in biofilms of environmental nonmucoid P. aeruginosa. In this study, we examined the chemical nature of the biofilm matrix produced by wild-type and isogenic alginate biosynthetic mutants of P. aeruginosa. The results clearly indicate that alginate biosynthetic genes are not expressed and that alginate is not required during the formation of nonmucoid biofilms in two P. aeruginosa strains, PAO1 and PA14, that have traditionally been used to study biofilms. Because nonmucoid P. aeruginosa strains are the predominant environmental phenotype and are also involved in the initial colonization in CF patients, these studies have implications in understanding the early events of the infectious process in the CF airway.  相似文献   
82.
Hypospadias urethroplasty is considered difficult as the complications and unfavourable results are not uncommon. At the turn of the century, due to a better understanding of applied anatomy of hypospadias, new techniques were developed which significantly brought down the complication rate. However unfavourable results are still disturbing. An algorithm for selection of surgery has been presented. Forty three secondary surgeries were performed over 3 years for correction of unfavourable results. The urethrocutaneous fistula was the most common (21%) followed by meatal stenosis (14%) and narrow neourethra (14%). Common unfavourable results have been discussed. On the basis of experience with a large number of hypospadias urethroplasty ‘tips to avoid or minimise unfavourable results’ have been presented. However, one should assess the final outcome of urethroplasty using hypospadias objective scoring evaluation.KEY WORDS: Complication, fistula, hypospadias, stenosis, stricture, unfavourable results, urethroplasty  相似文献   
83.
Virus Genes - In addition to polioviruses, non-polio enteroviruses (NPEVs) are frequently isolated from patients with acute flaccid paralysis (AFP) worldwide. In polio-free countries, there have...  相似文献   
84.
Perception of body-weight status is an important determinant of weight-related behaviours and may affect the burden of weight disturbances as a public-health problem. No study has assessed self-perception of the weight status regarding body-fat distribution among health workers to date. The aim of this study was to evaluate the association of the perception of weight and health status among 542 women working at health centres of Tehran. We assessed their perceived body-weight and health status and measured waist- and hip-circumference, weight, and height to calculate waist-to-hip ratio (WHR) as a measure of fat distribution and body mass index (BMI, kg/m2). Women reported their sociodemographic information, and the perceived weight and health status were compared with their actual fatness status, defined based on WHR and BMI, to determine misperception of weight status. Multivariate logistic regression models were performed to assess the predictive effects of various sociodemographic factors and actual fatness on the perception of weight and health status. The results showed that more than 40% of women with normal BMI overestimated their body-weight status while only 15.8% of these women had central obesity. BMI was the most important variable associated with misperceived weight status as normal-weight women had significantly more misperception (OR 8.16, 95% CI 4.82-13.82) than overweight/obese women. WHR did not show any significant relationships with perceived weight status. In addition, perception of health status was not associated with actual fatness indices. It is concluded, BMI was the main predictor of the perception of weight status in female employees. The importance of using body-fat distribution in the perceptions of weight and health status should be emphasized.Key words: Body mass index, Health centres, Perception of health status, Perception of weight status, Waist-to-hip ratio, Iran  相似文献   
85.
Increasing evidence suggests that apelin and ghrelin may participate in atherogenesis. We sought to investigate whether the serum levels of apelin and ghrelin are significantly different in patients with coronary artery disease (CAD) compared to patients with nonsignificant coronary stenosis and determine the correlation between these adipokines and the severity of coronary stenosis.The study population included 31 stable CAD patients, 38 unstable CAD patients, and 39 non-CAD subjects. Serum levels of apelin and ghrelin, fasting blood glucose, lipid parameters, hs-CRP and hematological indices were determined in all groups using routine standard laboratory procedures. Serum apelin levels were significantly lower in patient with unstable CAD (0.354 ± 0.063 ng/mL) compared to stable CAD patients (0.401 ± 0.045 ng/mL, p = 0.003) and non-CAD subjects (0.415 ± 0.055 ng/mL, p<0.001). In addition, serum apelin levels were inversely correlated with the severity of coronary stenosis in CAD patients (p<0.05). However, there was no significant difference in ghrelin levels among the 3 groups.This data may suggest that the presence of unstable CAD may be associated with lower serum apelin which may indicate the potential role of this peptide in the progression and destabilization of coronary plaques.  相似文献   
86.
(1) Background: Thailand has made significant progress in reducing the number of human and animal rabies cases. However, control and elimination of the last remaining pockets of dog-mediated rabies have shown to be burdensome, predominantly as a result of the large numbers of free-roaming dogs without an owner that cannot be restrained without special efforts and therefore remain unvaccinated. To reach these dogs, the feasibility, and benefits of oral rabies vaccination (ORV) as a complementary tool has been examined under field conditions. (2) Methods: ORV of dogs was tested in five study areas of four provinces in Thailand. In these areas, sites with free-roaming dogs were identified with the support of local municipal workers and dog caretakers. ORV teams visited each of five study areas and distributed rabies vaccine (SPBN GASGAS) in three bait formats that were offered to the dogs using a hand-out and retrieval model. The three bait types tested included: egg-flavored baits, egg-flavored baits pasted with commercially available cat liquid snack, and boiled-intestine baits. A dog offered a vaccine bait was considered vaccinated when the discarded sachet was perforated or if a dog chewed vaccine bait at least 5 times before it swallowed the bait, including the sachet. (3) Results: A total of 2444 free-roaming dogs considered inaccessible for parenteral vaccination were identified at 338 sites. As not all dogs were approachable, 79.0% were offered a bait; of these dogs, 91.6% accepted the bait and subsequently 83.0% were considered successfully vaccinated. (4) Conclusion: Overall, 65.6% of the free-roaming dogs at these sites were successfully vaccinated by the oral route. Such a significant increase of the vaccination coverage of the free-roaming dog population could interrupt the rabies transmission cycle and offers a unique opportunity to reach the goal to eliminate dog-mediated human rabies in Thailand by 2030.  相似文献   
87.
Induction of broad Th1 cellular immune responses and cytokines is crucial characteristics for vaccines against intracellular infections such as hepatitis C virus (HCV). Plants (especially oilseed tissues) and plant-immunomodulators (like oil bodies) offer cost-effective and scalable possibilities for the production of immunologically relevant and safe vaccine antigens and adjuvants, respectively. Herein, we provide data of the murine immunization by transgenic canola oilseed-derived HCV core protein (HCVcp) soluble extract (TSE) and Escherichia coli- derived rHCVcp in combination with Canola oil bodies (oil) compared to that of the Freund’s (FA) adjuvant. Mice immunized by TSE+ oil developed both strong humeral (IgG) and Th1-biased cellular responses, manifested by high levels of IFN-γ and lower IgG1/IgG2a ratio and IL-4 secretion. Results of the intracellular cytokine staining indicated that TSE+ oil immunization in mice triggered both CD4+ and CD8+ T cells to release IFN-γ, while CD4+ cells were mostly triggered when FA was used. Analyses by qRT-PCR indicated that a combination of rHCVcp/TSE with oil body induced high levels of IL-10 cytokines compared to that of the FA adjuvant. These characteristics are important properties for the design of an HCV vaccine candidate and indicate the potential of Canola-derived antigen and oil bodies in addressing these concerns.  相似文献   
88.

Introduction

Burn injuries are a major cause of preventable mortality worldwide. To implement preventive strategies, a detailed understanding of the rate and trend of fatal burn injuries is needed. The aim of this study was to determine the rate and trend of burn mortality at national and province level in Iran from 1990 to 2015.

Materials and Methods

The data were retrieved from various sources: the Death Registration System, cemetery databases, the Demographic and Health Survey and three national population and housing censuses. ICD-10 codes were converted to Global Burden of Disease (GBD) codes for comparability. After addressing the incompleteness of death data, statistical methods such as spatio-temporal modelling and Gaussian Process Regression (GPR) were applied to estimate the levels and trend of death and cause specific mortality.

Results

The number of deaths due to burning across Iran was 80,625, with a male to female ratio of 0.88, 0.94 and 1.14 in 1990, 1995 and 2015, respectively. The annual percentage change of age-standardized death rate from 1990 to 2015 was ?5.42% and ?4.22% in women and men, respectively. The burn-related age-standardized mortality rate decreased considerably from 5.97 in 1990 to 1.74 per 100,000 in 2015. The mortality rate due to burns was highest among those aged more than 85 years, especially in Ilam province.

Conclusion

This study showed a decline in burn mortality in Iran from 1990 to 2015. Continued efforts to reduce the burden of burns are needed to accelerate this progress and prevent injuries.  相似文献   
89.
Bone disorders have emerged as a worrisome complication in HIV-infected patients in recent years. It is not clear that HIV infection itself or antiretroviral treatment or both are causes of bone loss. However, most studies have found a high prevalence of osteopenia and osteoporosis in HIV/AIDS patients. The objectives of this study were to determine the prevalence of osteopenia and osteoporosis in HIV-infected patients either untreated or receiving Highly Active Antiretroviral Therapy as compared with HIV negative persons. We also assessed the factors associated with these conditions. Bone Mineral Density was assessed by Dual Energy X-Ray Absorptiometry scans at the hip and lumbar spine in 36 AIDS patients receiving antiretroviral therapy and 44 HIV infected patients not receiving antiretroviral therapy (na?ve patients) and 40 HIV negative individuals as control. Factors that affect BMD were also determined. Prevalence of osteopenia or osteoporosis in different regions was significantly higher in HIV/AIDS patients compared with HIV negative subjects (77.3% in HIV positive na?ve patients, 86.1% in HAART-treated patients and 60% in the control group, P=0.002). Mean serum alkaline phosphatase was higher in HIV/AIDS patients than the control group (P=0.003). Osteopenia and osteoporosis in HIV-infected patients were associated with duration of HIV infection (P<0.0001) and antiretroviral treatment (P=0.012). Prevalence of osteopenia and osteoporosis in HIV/AIDS patients was higher than HIV negative individuals. Osteopenia and osteoporosis in HIV/AIDS patients was associated with duration of HIV infection and antiretroviral treatment.  相似文献   
90.
Throughout the world, many migrant and mobile populations are at elevated risk for HIV. Iran has a large immigrant population from neighboring Afghanistan; however, few data exist on the prevalence of HIV in this community. In 2008, we conducted a study to assess the presence of HIV infection among 477 immigrants in a town to the northeast of Tehran using a rapid test in the field. HIV prevalence was 0.2% (95% CI 0.005-1.2) with one person HIV-positive. We recommend periodic HIV sero-surveillance with detailed behavioral measures for this population in the future.  相似文献   
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