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81.
Axenfeld–Rieger syndrome (ARS) is a rare autosomal dominant disorder, which encompasses a range of congential malformations affecting the anterior segment of the eye. ARS shows genetic heterogeneity and mutations of the two genes, PITX2 and FOXC1, are known to be associated with the pathogenesis. There are several excellent reviews dealing with the complexity of the phenotype and genotype of ARS. In this study, we will attempt to give a brief review of the clinical features and the relevant diagnostic approaches, together with a detailed review of published PITX2 and FOXC1 mutations.  相似文献   
82.
Drug-resistant tuberculosis is a serious problem throughout the world. Resistance to Rifampicin (RIF) is mainly caused by the mutations in the rpoB gene coding the beta-subunit of RNA polymerase. In this study, we aimed to detect the distribution of rpoB gene mutations in 80 RIF-resistant clinical Mycobacterium tuberculosis (MTB) isolates from Turkey. The rpoB gene was amplified by PCR and mutations leading to RIF resistance were determined by automated sequence analysis. A total of 72 of the 80 isolates (90%) were found to carry mutations in the amplified region, whereas eight isolates (10%) carried no mutations. Overall, 24 different missense mutations affecting 14 codons, and two deletion mutants were identified. Nine new mutations, six in the hot-spot region and three outside this region, were found. The codon numbers of the most frequently encountered mutations were 531 (51.4%), 526 (18.1%), 516 (13.9%), and 513 (12.5%). As a result, 90% of the RIF-resistant MTB isolates from the Turkish patients were found to carry a mutation in the rpoB gene, Ser531Leu being the most frequent one. Although molecular methods identify mutations leading to RIF resistance very quickly, results of the antimycobacterial susceptibility tests must be taken into consideration for the patients carrying no mutations in this region.  相似文献   
83.
Acinetobacter species other than Acinetobacter baumannii have rarely been reported to be associated with nosocomial outbreaks of bloodstream infections. Within a period of 1 week, seven Acinetobacter-like isolates were recovered from peripheral blood and catheter specimens of five patients at a neonatal intensive care unit (NICU) in a tertiary hospital in Turkey. All five patients had placement of central venous catheters and had received total parenteral nutrition before the onset of bacteremia. Two of the five patients died. Medical devices, tap water, aerators, water samples, various surfaces, intravenous fluids, and the hands of health care workers in the NICU were sampled and were culture negative for the bacterium. All seven of the isolates had identical biochemical reactions, antimicrobial susceptibility results, and pulsed-field gel electrophoresis patterns, indicating a clonal nosocomial outbreak. A panel of standard biochemical reaction profiles and three phenotypic commercial identification systems failed to identify these isolates. Phenotypically, the isolate differed from Acinetobacter ursingii by its hemolysis on sheep blood agar and its negative citrate utilization. Sequences of the full 16S rRNA gene, which contained at least three different gene copies with polymorphic sequences between nucleotide positions 70 and 206, were determined from the first recovered isolate. The complete 1,529- to 1,531-bp 16S rRNA gene sequences and partial 801-bp rpoB gene sequences had similarities of 99.5% and 97.2%, respectively, to an A. ursingii isolate. The DNA-DNA similarities of the strain against the type strain of A. ursingii were 64.7 and 68.7%, which were lower than the recommended threshold value of 70% for the definition of bacterial species. These data indicate that a novel Acinetobacter organism caused the nosocomial outbreak of bacteremia in the NICU unit. We propose the designation of Acinetobacter septicus sp. nov. for these isolates, with isolate AK001 as the type strain.  相似文献   
84.
Panton-Valentine leukocidin (PVL) is an important virulence determinant of Staphylococcus aureus. The aim of this study was to investigate the prevalence of PVL genes in clinical S. aureus isolates and to determine the staphylococcal chromosomal cassette mec (SCCmec) types of methicillin-resistant S. aureus (MRSA) strains obtained from inpatients and outpatients of two hospitals in Turkey. Of the 304 S. aureus strains (230 hospital acquired [HA] and 74 community-onset [CO]), 261 were MRSA and 43 were methicillin-sensitive S. aureus (MSSA). PVL positivity was determined in 12 (1 HA and 11 community acquired) strains. Eight were MRSA, and four were MSSA. Seven of the PVL-positive strains were isolated from wound specimens, four from urine, and one from synovial fluid. SCCmec type III (93.78%) was more prevalent among HA-MRSA strains, and SCCmec type IIIB (41.18%) was more prevalent among CO-MRSA strains. Pulsed-field gel electrophoresis patterns of the PVL-positive isolates were different. Our results indicate that PVL-positive strains are able to cause infection in nearly every system without the need for additional risk factors. Our PVL-positive CO-MRSA strains carry SCCmec types other than types IV and V. Due to the presence of PVL-positive strains in the hospitals, it is important to establish appropriate infection control measures to prevent their spread in the community and in hospitals.  相似文献   
85.
Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder. About 10% of ALS cases are familial (FALS) and the genetic defect is known only in approximately 20%-30% of these cases. The most common genetic cause of ALS is SOD1 (superoxide dismutase 1) mutation. Very recently, mutations of the optineurin gene (OPTN), which is involved in open-angle glaucoma, were identified in 3 Japanese patients/families with ALS, and subsequently in a few FALS patients of European descent. We found a heterozygous nonsense mutation (c.493C>T, p.Gln165X, exon 6) in the OPTN gene in a Danish patient with ALS, and the mutation segregated from his affected father. The p.Gln165X mutation could not be detected in 1070 healthy Danish controls, in 1000 Danish individuals with metabolic phenotypes or in 64 sporadic ALS (SALS) cases. The p.Gln165X mutation described in this study is the first mutation reported in a Danish family and is likely involved in disease pathogenesis. Until now, only few OPTN mutations have been associated with ALS. As the underlying genetic defect is known only in approximately 20%-30% of FALS families, further screening of these cases is necessary for establishing the contribution of OPTN mutations in disease pathogenesis.  相似文献   
86.
We report on an intellectually disabled girl with a de novo satellited chromosome 10 (10qs) and performed a review of the literature of the non-acrocentric satellited chromosomes (NASC). Satellites and stalks normally occur on the short arms of acrocentric chromosomes; however, the literature cites several reports of satellited non-acrocentric chromosomes, which presumably result from a translocation with an acrocentric chromosome. This is, to our knowledge, the third report of a 10qs chromosome. The phenotype observed in the proband prompted a search for a structural rearrangement of chromosome 10q. By microsatellite analysis we observed a 4 Mb deletion on the long arm of chromosome 10, approximately 145 kb from the telomere. FISH and array CGH analyses revealed a complex rearrangement involving in range from the centromere to the telomere: A 9.64 Mb 10q26.11-q26.2 duplication, a 1.3 Mb region with no copy number change, followed by a 5.62 Mb 10q26.2-q26.3 deletion and a translocation of satellite material. The homology between the repeat sequences at 10q subtelomere region and the sequences on the acrocentric short arms may explain the origin of the rearrangement and it is likely that the submicroscopic microdeletion and microduplication are responsible for the abnormal phenotype in our patient. The patient presented here, with a 15-year follow-up, manifests a distinct phenotype different from the 10q26 pure distal monosomy and trisomy syndromes.  相似文献   
87.
Research questionTo characterize mobile fertility tracking applications (apps) to determine the use of such apps for women trying to conceive by identifying the fertile window.DesignAn exploratory cross-sectional audit study was conducted of fertility tracking applications. Ninety out of a possible total 200 apps were included for full review. The main outcome measures were the underlying app method for predicting ovulation, the fertile window, or both, price to download and use the app, disclaimers and cautions, information and features provided and tracked, and app marketing strategies.ResultsAll the apps except one monitored the women’s menstrual cycle dates. Most apps only tracked menstrual cycle dates (n = 49 [54.4%]). The remainder tracked at least one fertility-based awareness method (basal body temperature, cervical mucus, LH) (n = 41 [45.6%]). Twenty-five apps measured dates, basal body temperature, LH and cervical mucus (27.8%). Seventy-six per cent of apps were free to download with free apps having more desirable features, tracking more measures and having more and better quality educational insights than paid apps. Seventy per cent of apps were classified as feminine apps, 41% of which were pink in colour.ConclusionsMobile fertility tracking apps are heterogenous in their underlying methods of predicting fertile days, the price to obtain full app functionality, and in content and design. Unreliable calendar apps remain the most commonly available fertility apps on the market. The unregulated nature of fertility apps is a concern that could be addressed by app regulating bodies. The possible benefit of using fertility apps to reduce time to pregnancy needs to be evaluated.  相似文献   
88.
The mixture of olive oil and lime cream has been traditionally used to treat external burns in the region of Hatay/Antakya and middle Anatolia. Olive oil and lime cream have been employed by many physicians to treat many ailments in the past. A limited number of studies have shown the antibacterial effect of olive oil and that it does not have any toxic effect on the skin. But we did not find any reported studies on the mixture of olive oil and lime cream. The aim of this paper is to investigate the cytotoxic and antibacterial activity of olive oil and lime cream individually or/and in combination in vitro conditions, by using disk-diffusion method and in cell culture. The main purpose in using this mixture is usually to clear burns without a trace. Agar overlay, MTT (Cytotoxicity assay) and antibacterial susceptibility tests were used to investigate the cytotoxic and antibacterial activity of olive oil and lime cream. We found that lime cream has an antibacterial activity but also cytotoxic on the fibroblasts. On the other hand olive oil has limited or no antibacterial effect and it has little or no cytotoxic on the fibroblasts. When we combined lime cream and olive oil, olive oil reduced its cytotoxic impact. These results suggest that mixture of olive oil and lime cream is not cytotoxic and has antimicrobial activity.  相似文献   
89.
Schistosomiasis affects nearly 40 million women of reproductive age. Many of these women are infected while pregnant and lactating. Several studies have demonstrated transplacental trafficking of schistosome antigens; however, little is known regarding how these antigens affect the developing fetus and placenta. To evaluate the impact of schistosomiasis on trophoblasts of the human placenta, we isolated primary trophoblast cells from healthy placentas delivered at term. These trophoblasts were placed in culture and treated with Schistosoma japonicum soluble egg antigens (SEA) or plasma from S. japonicum-infected pregnant women. Outcomes measured included cytokine production and activation of signal transduction pathways. Treatment of primary human trophoblast cells with SEA resulted in upregulation of the proinflammatory cytokines interleukin 6 (IL-6) and IL-8 and the chemokine macrophage inflammatory protein 1α (MIP-1α). Cytokine production in response to SEA was dose dependent and reminiscent of production in response to other proinflammatory stimuli, such as Toll-like receptor 2 (TLR2) and TLR4 agonists. In addition, the signaling pathways extracellular signal-regulated kinase 1/2 (ERK1/2), Jun N-terminal protein kinase (JNK), p38, and NF-κB were all activated by SEA in primary trophoblasts. These effects appeared to be mediated through both carbohydrate and protein epitopes of SEA. Finally, primary trophoblasts cocultured with plasma from S. japonicum-infected pregnant women produced increased levels of IL-8 compared to trophoblasts cocultured with plasma from uninfected pregnant women. We report here a direct impact of SEA on primary human trophoblast cells, which are critical for many aspects of a healthy pregnancy. Our data indicate that schistosome antigens can activate proinflammatory responses in trophoblasts, which might compromise maternal-fetal health in pregnancies complicated by schistosomiasis.  相似文献   
90.
Tourette syndrome (TS) is a childhood onset neurodevelopmental disorder. Although it is widely accepted that genetic factors play a significant role in TS pathogenesis the etiology of this disorder is largely unknown. Identification of rare copy number variations (CNVs) as susceptibility factors in several neuropsychiatric disorders such as attention deficit‐hyperactivity disorder (ADHD), autism and schizophrenia, suggests involvement of these rare structural changes also in TS etiology. In a male patient with TS, ADHD, and OCD (obsessive compulsive disorder) we identified two microduplications (at 15q13.3 and Xq21.31) inherited from a mother with subclinical ADHD. The 15q duplication included the CHRNA7 gene; while two genes, PABPC5 and PCDH11X, were within the Xq duplication. The Xq21.31 duplication was present in three brothers with TS including the proband, but not in an unaffected brother, whereas the 15q duplication was present only in the proband and his mother. The structural variations observed in this family may contribute to the observed symptoms, but further studies are necessary to investigate the possible involvement of the described variations in the TS etiology. © 2013 Wiley Periodicals, Inc.  相似文献   
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