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The Human Leukocyte Antigen (HLA) typing of large groups of patients with various autoimmune diseases has demonstrated that some HLA alleles occur at higher frequencies in specific diseases than in the general population. Chronic urticaria has been shown to have an autoimmune basis by a previous study which found an association between chronic urticaria and specific HLA groups. We investigated the HLA subtypes of Turkish chronic urticaria patients. For this purpose 42 Turkish patients with chronic urticaria and 115 healthy controls were typed for HLA-DR and DQ by PCR-SSP (Polymerase Chain Reaction Sequence Specific Primers) low resolution DNA technique. We found an increased frequency of DR4 (42.9%, p=0.01) in chronic urticaria patients in comparison with that in healthy controls. This study supports the hypothesis that HLA alleles may be involved in the pathogenesis of chronic urticaria and that they appear to be directly involved in the initiation of the immune response. 相似文献
3.
Karahan ZC Atalay F Uzun M Erturan Z Atasever M Akar N 《Microbial drug resistance (Larchmont, N.Y.)》2004,10(4):325-333
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
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Meltem Yüksel Elma Baron Melissa Camouse Brenda W Cooper Hillard M Lazarus Stanton L Gerson Mary J Laughlin Kevin D Cooper Anita Gilliam Pingfu Fu Seth Stevens Omer N Ko? 《Biology of blood and marrow transplantation》2006,12(6):665-671
Whole-body UV-B phototherapy has been used for the treatment of graft-versus-host disease (GVHD) of the skin and has systemic immunosuppressive and tolerogenic effects. We hypothesized that whole-body UV-B therapy would improve donor engraftment and decrease the incidence and severity of GVHD that is associated with decreased intensity allogeneic hematopoietic stem cell transplantation. This study tested the feasibility of using UV-B phototherapy that was initiated before grafting and continued until engraftment to determine its effect on transplantation outcome. Eight patients (median age, 55.5 years; range, 32-65 years) with hematologic malignancies were included. Allogeneic peripheral blood stem cells were obtained from matched related (n=5) or matched unrelated (n=3) donors. Conditioning regimen was fludarabine 30 mg/m2 intravenously for 5 days, cyclophosphamide 1 g/m2/d intravenously for 2 days, and equine antithymocyte globulin 30 mg/kg/d for 2 days. GVHD prophylaxis included cyclosporine, methylprednisolone, and escalating doses of narrowband UV-B (311 nm) according to skin tolerance, 3 days a week, from 10 days before to 28 days after transplantation. The conditioning regimen and the UV-B therapy were well tolerated. Two patients received all 14 prescribed UV-B treatments (cumulative doses of 2000 and 3260 mJ/cm2, respectively) and 6 patients received 8 to 13 treatments with a cumulative dose range of 528-3465 mJ/cm2. There was a rapid decrease in epidermal CD1a+ cells by day of transplantation. Myeloid engraftment was rapid. One patient had secondary engraftment failure at 3 months and another had mixed chimerism at day 100. Seven of 8 patients developed severe acute GVHD (grade III, n=5; grade IV, n=2). Six had skin involvement, 5 had gastrointestinal involvement, and 1 had liver involvement. Four patients died (2 from sepsis, 1 from acute GVHD, and 1 from chronic GVHD). Four patients are alive (130-287 days), 3 with extensive chronic GVHD. We conclude that extended peritransplant UV-B therapy at the standard minimally erythemogenic dose is detrimental to the outcome of allogeneic stem cell transplantation. It is unclear how UV-B at this immunsuppressive dose might have altered skin and systemic cytokine and immune cell compositions in the host and increased GVHD- and treatment-related mortalities. Different UV-B dose and schedules should be further explored. However, although other phototherapeutic modalities may be effective against GVHD, extended UV-B therapy should not be used during early phases of decreased conditioning allogeneic transplantation. 相似文献
5.
Meltem Dinleyici Vicente Prez-Brocal Sertac Arslanoglu Ozge Aydemir Sibel Sevuk Ozumut Neslihan Tekin Yvan Vandenplas Andrs Moya Ener Cagri Dinleyici 《Nutrients》2021,13(6)
The human milk (HM) microbiota is a significant source of microbes that colonize the infant gut early in life. The aim of this study was to compare transient and mature HM virome compositions, and also possible changes related to the mode of delivery, gestational age, and weight for gestational age. Overall, in the 81 samples analyzed in this study, reads matching bacteriophages accounted for 79.5% (mainly Podoviridae, Myoviridae, and Siphoviridae) of the reads, far more abundant than those classified as eukaryotic viruses (20.5%, mainly Herpesviridae). In the whole study group of transient human milk, the most abundant families were Podoviridae and Myoviridae. In mature human milk, Podoviridae decreased, and Siphoviridae became the most abundant family. Bacteriophages were predominant in transient HM samples (98.4% in the normal spontaneous vaginal delivery group, 92.1% in the premature group, 89.9% in the C-section group, and 68.3% in the large for gestational age group), except in the small for gestational age group (only ~45% bacteriophages in transient HM samples). Bacteriophages were also predominant in mature HM; however, they were lower in mature HM than in transient HM (71.7% in the normal spontaneous vaginal delivery group, 60.8% in the C-section group, 56% in the premature group, and 80.6% in the large for gestational age group). Bacteriophages still represented 45% of mature HM in the small for gestational age group. In the transient HM of the normal spontaneous vaginal delivery group, the most abundant family was Podoviridae; however, in mature HM, Podoviridae became less prominent than Siphoviridae. Myoviridae was predominant in both transient and mature HM in the premature group (all C-section), and Podoviridae was predominant in transient HM, while Siphoviridae and Herpesviridae were predominant in mature HM. In the small for gestational age group, the most abundant taxa in transient HM were the family Herpesviridae and a species of the genus Roseolovirus. Bacteriophages constituted the major component of the HM virome, and we showed changes regarding the lactation period, preterm birth, delivery mode, and birth weight. Early in life, the HM virome may influence the composition of an infant’s gut microbiome, which could have short- and long-term health implications. Further longitudinal mother–newborn pair studies are required to understand the effects of these variations on the composition of the HM and the infant gut virome. 相似文献
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Introduction: Chronic progressiveexternal ophthalmoplegia is characterisedby limitation of ocular motility in alldirections of gaze and ptosis.Innervational or myogenic factors wereclaimed to be responsible for thismotility disorder. The aim of thisstudy was toinvestigate the extraocular muscles inCPEO with computerized tomography in an attemptto distinguish extraocular musclemorphology caused by this disorderfrom that occurring in normal individuals.Methods: Eighteen orbits from 9patients diagnosed with CPEOwere included in the study. Axialand coronal scans were obtained for CTevaluation of extraocular muscles and thedimensions of extraocular muscles were measured.The control group consisted of40 orbits belonging to 20 individuals and,the results were compared with a student'st test.Results: The thickness (the verticaldimension of vertical recti and thehorizontal dimension of horizontal recti)of all rectus muscles wassignificantly decreased in comparison with the controlgroup, whereas the width (the horizontal dimensionof vertical recti and the verticaldimension of horizontal recti) was similar inboth the diseased and normal orbits.In all the rectus musclesof the diseased orbits,the normal fusiform shape was lost and the muscles appeared asthin bands.Discussion: The differentiation ofCPEO from other myogenic and neurogenicdisorders may present difficulty,and a cluster of criteria are required fora final diagnosis. CT has provento be a valuable tool in assessing extraocularmuscles [1, 2]. In this study, an extremeatrophy of all rectus muscles wasdemonstrated by means of CT. This diagnostic method mayconsequently contribute to a properdiagnosis of CPEO. 相似文献
8.
Ozlem Dural Funda Gungor Ugurlucan Cenk Yasa Ercan Bastu Hulya Eren Bahar Yuksel Serdal Celik Suleyman Engin Akhan 《Journal of pediatric and adolescent gynecology》2017,30(1):e7-e10
Background
Isolated distal vaginal agenesis is a rare anomaly and mostly becomes symptomatic after menarche. We describe an unusual presentation of this anomaly in a prepubertal girl.Case
An 11-year-old prepubertal girl presented with recurrent urinary tract infection, pyuria, and right-sided renal agenesis. The findings of perineal inspection, ultrasonography, and magnetic resonance imaging were consistent with a distal vaginal agenesis with pyometrocolpos. Discharging pyometrocolpos with dissection of the atretic portion and a pull-through vaginoplasty were performed. A cystoscopy showed no sign of a vesicovaginal or uterine fistula.Summary and Conclusion
This rare presentation of distal vaginal agenesis reminds us that congenital malformations of the female genital tract should be considered in patients with congenital anomalies of the urinary system and/or recurrent urinary tract infection, even during the prepubertal period. 相似文献9.
Nitrogen doped carbon nanoparticles on highly porous carbon nanofiber electrodes were successfully synthesized via combining centrifugal spinning, chemical polymerization of pyrrole and a two-step heat treatment. Nanoparticle-on-nanofiber morphology with highly porous carbon nanotube like channels were observed from SEM and TEM images. Nitrogen doped carbon nanoparticles on highly porous carbon nanofiber (N-PCNF) electrodes exhibited excellent cycling and C-rate performance with a high reversible capacity of around 280 mA h g−1 in sodium ion batteries. Moreover, at 1000 mA g−1, a high reversible capacity of 172 mA h g−1 was observed after 300 cycles. The superior electrochemical properties were attributed to a highly porous structure with enlarged d-spacings, enriched defects and active sites due to nitrogen doping. The electrochemical results prove that N-PCNF electrodes are promising electrode materials for high performance sodium ion batteries.Nitrogen doped carbon nanoparticles on highly porous carbon nanofiber electrodes were successfully synthesized via combining centrifugal spinning, chemical polymerization of pyrrole and a two-step heat treatment. 相似文献
10.
Koygun Gozde Kayadibi Kars Meltem Demirel Emsen Ayca Artac Hasibe Aksoy Faruk Cakir Murat Tavli Lema Artac Mehmet 《Clinical and experimental medicine》2021,21(3):447-456
Clinical and Experimental Medicine - Breast cancer (BC) is the leading cause of cancer deaths in women. One of the reasons for the failure of BC treatment is reportedly the ineffectiveness of... 相似文献