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51.
OBJECTIVES: To assess the occurrence of extended-spectrum beta-lactamases (ESBLs) in Escherichia coli isolates of faecal samples of animals (n = 40) and food samples (n = 38) obtained in Tunisia in 2006, and to characterize the type of ESBLs, their genetic environments and the associated resistance genes. METHODS: Samples were inoculated in supplemented media (2 mg/L cefotaxime) for isolation of broad-spectrum cephalosporin-resistant E. coli isolates (one isolate/sample). ESBLs and their genetic environments as well as integrons and their gene cassette composition were characterized by PCR and sequencing. RESULTS: ESBL-producing E. coli isolates were detected in 10 of the 38 food samples analysed (26%) and in none of the tested animal faecal samples. Genes found were as follows (number of isolates): bla(CTX-M-1) (5), bla(CTX-M-1) + bla(TEM-1b) (1), bla(CTX-M-14) + bla(TEM-1b) (2), bla(CTX-M-8) (1) and bla(SHV-5) (1). All ESBL-positive isolates showed unrelated PFGE patterns. ISEcp1 and IS903 were detected surrounding bla(CTX-M-14), and ISEcp1/IS26 and orf477 surrounding some of the bla(CTX-M-1) genes. Four of the ESBL-positive strains harboured class 1 integrons including different gene cassette combinations. CONCLUSIONS: ESBLs, mainly of the CTX-M class, are detected in E. coli of food origin in Tunisia, being the first time that this mechanism has been detected in food E. coli strains in Africa.  相似文献   
52.
53.

Objective

The determination of the cellular lineage in acute leukemia is a crucial step in the diagnosis and the later therapeutic conduct. In Tunisia, emerging country, some cases of acute leukemias are still treated on the basis of an only cytologic study because of lack of cytometry. Our objective is to realize a confrontation between cytology and flow cytometry in the diagnosis of AL and to analyze discrepancies.

Patients and methods

The study concerns 100 cases of AL. A second double-blind examination of the bone marrow smears of acute leukemias is realized by two cytologists and confronted to immunophenotyping.

Results

In two cases of AML, flow cytometry reassigned lineage into T ALL and biphenotypic AL. In three cases of ALL the lineage was reassigned into undifferentiated acute leukemia (2 cases) and biphenotypic acute leukemia (1 case). Lineage was not established in four cases, immunophenotyping allowed the diagnosis of B ALL in 3 cases, and of biphenotypic acute leukemia in 1 case. In both cases of discrepant findings, flow cytometry allowed the diagnosis of biphenotypic acute leukemia in a case and of AML in the other one.

Conclusion

The cytological study remains insufficient in the diagnosis of lineage even with experimented cytologists. Immunophenotyping is essential in lineage assignment and reassignment.  相似文献   
54.
The family of non‐classical major histocompatibility complex (MHC) class‐I like CD1 molecules has an emerging role in human disease. Group 1 CD1 includes CD1a, CD1b and CD1c, which function to display lipids on the cell surface of antigen‐presenting cells for direct recognition by T‐cells. The recent advent of CD1 tetramers and the identification of novel lipid ligands has contributed towards the increasing number of CD1‐restricted T‐cell clones captured. These advances have helped to identify novel donor unrestricted and semi‐invariant T‐cell populations in humans and new mechanisms of T‐cell recognition. However, although there is an opportunity to design broadly acting lipids and harness the therapeutic potential of conserved T‐cells, knowledge of their role in health and disease is lacking. We briefly summarize the current evidence implicating group 1 CD1 molecules in infection, cancer and autoimmunity and show that although CD1 are not as diverse as MHC, recent discoveries highlight their versatility as they exhibit intricate mechanisms of antigen presentation.  相似文献   
55.
Terminal deletions of the chromosome 6q27 region are rare genomic abnormalities, linked to specific brain malformations and other neurological phenotypes. Reported cases have variable sized genomic deletions that harbor several genes including the DLL1 and TBP. We report on an inherited 0.38 Mb terminal deletion of chromosome 6q27 in a 22‐week fetus with isolated bilateral ventriculomegaly and her affected mother using microarray‐based comparative genomic hybridization and fluorescent in situ hybridization (FISH). The deleted region harbors at least seven genes including DLL1 and TBP. The affected mother had a history of hydrocephalus, developmental delay, and seizures commonly associated with DLL1 and TBP 6q27 deletions. This deletion is one of the smallest reported isolated 6q27 terminal deletions. Our data provides additional evidence that haploinsufficiency of the DLL1 and TBP genes may be sufficient to cause the ventriculomegaly, seizures, and developmental delays associated with terminal 6q27 deletions, indicating a plausible role in the abnormal development of the central nervous system.  相似文献   
56.

Objective

To evaluate the rate and pattern of complications associated with use of the Copper T 380A intrauterine device (IUD) among adolescents.

Methods

A prospective comparative study of women eligible for IUD insertion who attended the family planning clinic of Sohag University Hospital, Egypt, between July 1, 2008 and December 31, 2010. The participants were categorized as adolescents or adults. The Copper T 380A IUD was inserted in all participants and follow-up visits were scheduled at 1, 3, and 6 months. Odds ratio and χ2 square tests were used to compare the rates of complications at each visit.

Results

Of 1512 patients eligible for IUD insertion, 852 met the inclusion criteria: 281 adolescents and 571 adults. The rates of pain, bleeding, displacement, expulsion, and removal of IUDs were significantly higher in adolescents (P < 0.05). The rates of these complications were high in adolescents younger than 16 years; the rates then decreased with age and became comparable with the adult rates at 18 years of age.

Conclusions

IUD-associated complications were high in adolescents up to the age of 17 years. Our data suggest that adolescents younger than 18 years of age should be counseled carefully before IUD insertion, and examined more frequently to detect displacement or expulsion of the device.  相似文献   
57.

Objective

To determine the reasons for adolescent pregnancy in Upper Egypt and to evaluate maternal, fetal, and neonatal outcomes.

Methods

All primigravidae under 30 years of age who attended the labor/delivery ward at Sohag University Hospital, Sohag, Egypt, between December 31, 2005, and December 31, 2009, were invited to participate. Participants were allocated to the study group (up to 19 years of age at first pregnancy) or the control group (20-30 years of age at first pregnancy). Maternal, obstetric, fetal, and neonatal complications were compared between the groups, and adolescent participants completed a questionnaire to identify the reasons for pregnancy.

Results

In total, 58.2% had married seeking motherhood. Rates of ectopic pregnancy, pre-eclampsia, eclampsia, premature rupture of membranes, preterm labor, and cesarean were significantly higher among adolescents younger than 15 years of age; the risk then decreased steadily with age and became comparable to the control group after 16 years of age.

Conclusion

Adolescent pregnancy increases the risk of ectopic pregnancy, pre-eclampsia, eclampsia, premature rupture of membranes, preterm labor, and cesarean among mothers up to 16 years of age. After 16 years of age, pregnancy is not associated with increased risk of obstetric or neonatal complications.  相似文献   
58.

Objective

To estimate the influence of the 2007 criminalization law on the prevalence and yearly incidence of female genital mutilation (FGM) in Upper Egypt and assess the attitudes of both the population and their health providers toward FGM.

Methods

Between September 15, 2008, and September 15, 2010, all girls and young women presenting at the Departments of Gynecology and Obstetrics or Pediatrics of Sohag and Qena University Hospitals were invited to answer a questionnaire, which was also presented to their parents. Another questionnaire was presented to all nurses, young physicians, and senior physicians working at either hospital.

Results

The prevalence of FGM was 89.2%. The incidence was 9.6% in 2000, began to decrease in 2006, and had reached 7.7% at the end of the study period in 2009 (P = 0.05). In their vast majority, the procedures were performed by general practitioners. In total, 88.2%, 34.3% and 14.9% of nurses, young physicians, and senior physicians, respectively, approved the practice.

Conclusion

The incidence of FGM is still very high in Upper Egypt in spite of the criminalization law. While general practitioners perform most procedures, most nurses are in favor of preserving the practice.  相似文献   
59.
We investigated unusual crow mortality in Bangladesh during January-February 2011 at two sites. Crows of two species, Corvus splendens and C. macrorhynchos, were found sick and dead during the outbreaks. In selected crow roosts, morbidity was ~1 % and mortality was ~4 % during the investigation. Highly pathogenic avian influenza virus H5N1 clade 2.3.2.1 was isolated from dead crows. All isolates were closely related to A/duck/India/02CA10/2011 (H5N1) with 99.8 % and A/crow/Bangladesh/11rs1984-15/2011 (H5N1) virus with 99 % nucleotide sequence identity in their HA genes. The phylogenetic cluster of Bangladesh viruses suggested a common ancestor with viruses found in poultry from India, Myanmar and Nepal. Histopathological changes and immunohistochemistry staining in brain, pancreas, liver, heart, kidney, bursa of Fabricius, rectum, and cloaca were consistent with influenza virus infection. Through our limited investigation in domesticated birds near the crow roosts, we did not identify any samples that tested positive for influenza virus A/H5N1. However, environmental samples collected from live-bird markets near an outbreak site during the month of the outbreaks tested very weakly positive for influenza virus A/H5N1 in clade 2.3.2.1-specific rRT-PCR. Continuation of surveillance in wild and domestic birds may identify evolution of new avian influenza virus and associated public-health risks.  相似文献   
60.
Although matured DC are capable of inducing effective primary and secondary immune responses in vivo, it is difficult to control the maturation and antigen loading in vitro. In this study, we show that ER‐enriched microsomal membranes (microsomes) isolated from DC contain more peptide‐receptive MHC I and II molecules than, and a similar level of costimulatory molecules to, their parental DC. After loading with defined antigenic peptides, the microsomes deliver antigenic peptide–MHC complexes (pMHC) to both CD4 and CD8 T cells effectively in vivo. The peptide‐loaded microsomes accumulate in peripheral lymphoid organs and induce stronger immune responses than peptide‐pulsed DC. The microsomal vaccines protect against acute viral infection. Our data demonstrate that peptide–MHC complexes armed microsomes from DC can be an important alternative to DC‐based vaccines for protection from viral infection.  相似文献   
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