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51.

Background

Resistance to antimicrobial agents such as carbapenems among enterobacteriacea has been increasing, especially in Klebsiella pneumonia that produces variety of enzymes including Klebsiella pneumoniae carbapenemase (KPC). This study is the first report of its kind investigating the resistance to carbapenems among burns patients in Iran.

Method

During a 6-month period, 28 hospitalized burn patients who required to be placed on broad spectrum antibiotics were studied. Isolated species identified by routine biochemical test. Susceptibility testing for these species was performed by recommended the CLSI guidelines method. The tested antibiotics included cefotaxime, cefepime, aztreonam, imipenem, amoxicillin + clavulonic acid, gentamicin, amikacin, tobramycin, tetracycline, and trimethoprim-sulfamethoxazole, and chloramphenicol. For determination of KPC in phenotypical forms, Modified Hodge Test was utilized as per CLSI recommendation.

Results

Thirty-five Klebsiella spp. were isolated from 28 hospitalized patients. Nineteen out of 35 Klebsiella isolates were resistant to imipenem and that all of them had positive KPC. Nine of imipenem resistant isolates were also resistant to all tested antibiotics. Mortality rate among patients with positive KPC was 33%.

Conclusion

High rate of multi-drug resistant (MDR) strains in isolates with positive KPC is a major challenge in Iran and that it could cause an increase in both mortality and morbidity among burn patients. Thus, appropriate infection control measures and guidelines are needed to prevent such infections among burn patients.  相似文献   
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Salmonella enterica serovar Virchow is highly prevalent in humans and farm animals in Israel. In addition to high rates of resistance to multiple antibiotics, this serovar exhibits a high incidence of resistance to nalidixic acid. More than 90% of Salmonella serovar Virchow isolates of human and poultry origin obtained from 1997 to 2004 were resistant to nalidixic acid (MIC > or = 128 microg/ml), with reduced susceptibility to ciprofloxacin (MIC between 0.125 and 0.250 microg/ml). Most isolates belonged to two predominant, closely related pulsed-field gel electrophoresis image types. Investigation of the mechanisms of quinolone resistance revealed that this pathogen probably emerged from a parental clone that overproduced the AcrAB efflux pump and had a single point mutation in gyrA leading to the Asp87Tyr substitution. The close resemblance between human and poultry isolates points to poultry as a likely source of Salmonella serovar Virchow in the food chain.  相似文献   
55.

Background

To propose health system strategies to meeting the World Health Organization (WHO) recommendations on HIV screening through antenatal care (ANC) services, we assessed predictors of HIV screening, and simulated the impact of changes in these predictors on the probability of HIV screening in Guatemala, Honduras, Mexico (State of Chiapas), Nicaragua, Panama, and El Salvador.

Methods

We interviewed a representative sample of women of reproductive age from the poorest Mesoamerican areas on ANC services, including HIV screening. We used a multivariate logistic regression model to examine correlates of HIV screening. First differences in expected probabilities of HIV screening were simulated for health system correlates that were associated with HIV screening.

Results

Overall, 40.7% of women were screened for HIV during their last pregnancy through ANC. This rate was highest in El Salvador and lowest in Guatemala. The probability of HIV screening increased with education, household expenditure, the number of ANC visits, and the type of health care attendant of ANC visits. If all women were to be attended by a nurse, or a physician, and were to receive at least four ANC visits, the probability of HIV screening would increase by 12.5% to reach 45.8%.

Conclusions

To meet WHO’s recommendations for HIV screening, special attention should be given to the poorest and least educated women to ensure health equity and progress toward an HIV-free generation. In parallel, health systems should be strengthened in terms of testing and human resources to ensure that every pregnant woman gets screened for HIV. A 12.5% increase in HIV screening would require a minimum of four ANC visits and an appropriate professional attendance of these visits.
  相似文献   
56.

Background

Newborn screening for sickle cell anemia is necessary in Africa where the disease is more frequent. Hemoglobin electrophoresis is used for screening, but is limited by a high cost and difficult access. Sickling test (Emmel test), which is more affordable and technically more accessible, is often requested for prenatal assessment of pregnant women in West African areas to reserve screening for newborns from mothers in whom the positive sickling test attests the presence of hemoglobin S. This study aims to evaluate the number of undetected sickle cell anemia newborns by a screening policy targeting only newborns from mothers in whom a sickling test would have been positive.

Methods

From 2010 to 2012, in Bamako, Mali, West Africa, 2489 newborns were routinely screened for sickle cell anemia at the umbilical cord or heel by isoelectrofocusing and, if necessary, by high-performance liquid chromatography. These newborns were born from 2420 mothers whose hemoglobin was studied by isoelectrofocusing. The data was recorded and processed using Excel software version 14.0.0. We calculated the frequency of the sickle cell gene in mothers and newborns as well as the number of SCA newborns from heterozygous or C homozygous mothers.

Results

Of the 2489 newborns, 16 had sickle cell anemia (6 SS and 10 SC); 198 had the sickle cell trait; 139 were AC and 1 was CC. Of the 10 newborns with SC profile, 3 were born from mothers not carrying the S gene but the C gene of hemoglobin and in which an Emmel test would have been negative.

Conclusion

Targeted newborn screening, based on the results of sickling test in pregnant women, would misdiagnose more than one of six sickle cell anemia newborns who would not benefit from early care. Cost-effectiveness studies of routine newborn screening for sickle cell anemia should lead to a better screening strategy in contexts where hemoglobin S and other hemoglobin defect genes coexist.  相似文献   
57.
A case-cohort study, within a multi-country trial of antiretroviral therapy (ART) efficacy (Prospective Evaluation of Antiretrovirals in Resource Limited Settings (PEARLS)), was conducted to determine if pre-ART serum selenium deficiency is independently associated with human immunodeficiency virus (HIV) disease progression after ART initiation. Cases were HIV-1 infected adults with either clinical failure (incident World Health Organization (WHO) stage 3, 4 or death by 96 weeks) or virologic failure by 24 months. Risk factors for serum selenium deficiency (<85 μg/L) pre-ART and its association with outcomes were examined. Median serum selenium concentration was 82.04 μg/L (Interquartile range (IQR): 57.28–99.89) and serum selenium deficiency was 53%, varying widely by country from 0% to 100%. In multivariable models, risk factors for serum selenium deficiency were country, previous tuberculosis, anemia, and elevated C-reactive protein. Serum selenium deficiency was not associated with either clinical failure or virologic failure in multivariable models. However, relative to people in the third quartile (74.86–95.10 μg/L) of serum selenium, we observed increased hazards (adjusted hazards ratio (HR): 3.50; 95% confidence intervals (CI): 1.30–9.42) of clinical failure but not virologic failure for people in the highest quartile. If future studies confirm this relationship of high serum selenium with increased clinical failure, a cautious approach to selenium supplementation might be needed, especially in HIV-infected populations with sufficient or unknown levels of selenium.  相似文献   
58.

Purpose

The aim of this study was the development of poly(D,L-lactide-co-glycolide) (PLGA) microspheres with controlled porosity, to obtain microspheres that afford continuous release of a macromolecular model compound (blue dextran).

Methods

PLGA microspheres with a size of around 40 μm and narrow size distribution (span value of 0.3) were prepared with a double emulsion membrane emulsification method. Gene expression programming (GEP) analysis was applied to design and formulate a batch of microspheres with controlled porosity that shows continuous release of blue dextran.

Results

Low porous microspheres with a high loading efficiency were formed at high polymer concentrations (30% w/w in the oil phase) and were characterized with a burst release <10% and a three-phasic release profile of blue dextran. Increasing porosity (10% w/w polymer concentrations), a sustained release of blue dextran was obtained albeit with up to 40% of burst release. The desired formulation, calculated by GEP, resulted in microspheres with 72% loading efficiency and intermediate porosity. Blue dextran was indeed released continuously in almost a zero order manner over a period of 3 months after an initial small burst release of 9%.

Conclusions

By fine-tuning the porosity, the release profile of PLGA microspheres for macromolecules can be predicted and changed from a three-phasic to a continuous release.  相似文献   
59.
In a phase 2 study, 62 patients with relapsed and refractory acute myeloid leukemia (AML; n = 31), myelodysplastic syndrome (MDS; n = 8), chronic myeloid leukemia in blastic phase (CMLBP; n = 11), and acute lymphocytic leukemia (ALL; n = 12) received 40 mg/m2 clofarabine intravenously over 1 hour daily for 5 days, every 3 to 6 weeks. Twenty patients (32%) achieved complete response (CR), 1 had a partial response (PR), and 9 (15%) achieved CR but without platelet recovery (CRp), for an overall response rate of 48%. In AML, responses were noted in 2 (18%) of 11 patients in first salvage with short first CR (相似文献   
60.
BACKGROUND/AIMS: Although a "hospital-based cancer registry" is important in improving patient care, a "population-based cancer registry" with emphasis on epidemiology is important in allocating health care resources and prioritizing public health programs. Because of its reliance on retrieved clinical and para-clinical documents, there is some limitation in registering all cancer incidents in this system, especially in developing countries. In this study we examined the possibility of using public data as a complementary source of information for recording cancers in a population-based cancer registry. METHODS: Along with the annual census in rural areas, a survey was performed in Golestan province in March 2004 to identify public awareness about cancer incidents in the community. Individuals were questioned about history of cancer in their close relatives during the last two years. Those who reported cancer in their relatives were also asked to name the main organ of involvement. A similar list was retrieved from the cancer registry at the Ministry of Health in Gorgan, and cases with upper GI (esophagus and gastric) cancer diagnosis from 21 March 2002 through 20 March 2004 were selected for this study. Finally, these two lists were compared for examining accuracy of the collected data. RESULTS: We included 137 cases in our study with rural residence and known addresses. Only 35 (25.5%) cases were reported by the relatives and among them only 20 (57.1%) relatives correctly reported the tumor location. Although we found a difference in accurate reporting of cancer incidents by year of diagnosis (more correct cases reported during the second versus the first year), the difference was not statistically significant between the two years. CONCLUSION: In this study, we examined the possibility of using public awareness about cancer incidents as a complementary source of information for a population-based cancer registry. We found that this approach is not ideal for reducing limitations. Therefore, we recommend a nationwide cancer registry to record all cancer-related information at the time of diagnosis. This strategy will reduce the need for performing retrospective surveys in collecting cancer-related information.  相似文献   
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