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DNA and FISH (fluorescence in situ hybridization) analysis were carried out in 12 patients with stigmata of Turner syndrome to determine whether the Supernumerary M arker C hromosome (SMC) found cytogenetically in each of these patients was derived from the Y chromosome. The presence of a Y chromosome in these patients may predispose them to develop gonadoblastoma. PCR-Southern blot analysis, followed by FISH, was used to detect the presence of Y chromosome material. The S ex determining R egion Y (SRY), T estis S pecific P rotein Y -encoded (TSPY) and Y -chromosome R NA R ecognition M otif (YRRM) genes, which map at Yp11.31, Yp11.1–11.2 and Yp11.2/Yq11.21–11.23, respectively, were selected as markers, because they span the whole Y chromosome, and more importantly, they are considered to be involved in the development of gonadoblastoma. It was shown that in 12 patients, all of whom had an SMC, the SMC of 11 was derived from the Y chromosome. Furthermore, the presence of the SRY, TSPY and YRRM gene sequences was determined and FISH analysis confirmed the Y origin of the SMCs. The methodology described in this report is a rapid, reliable and sensitive approach which may be easily applied to determine the Y origin of an SMC carried in Turner syndrome. The identification of an SMC is important for the clinical management and prognostic counseling of these patients with Turner syndrome.  相似文献   
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The presence of Y chromosome sequences in Turner syndrome (TS) patients may predispose them to gonadoblastoma formation with an estimated risk of 15–25%. The aim of this study was to determine the presence and the incidence of cryptic Y chromosome material in the genome of TS patients. The methodology involved a combination of polymerase chain reaction (PCR) and nested PCR followed by Southern blot analysis of three genes—the sex determining region Y (SRY), testis specific protein Y encoded (TSPY) and RNA binding motif protein (RBM) (previously designated as YRRM) and nine additional STSs spanning all seven intervals of the Y chromosome. The methodology has a high sensitivity as it detects one 46, XY cell among 105 46, XX cells. Reliability was ensured by taking several precautions to avoid false positive results. We report the results of screening 50 TS patients and the identification of cryptic Y chromosome material in 12 (24%) of them. Karyotypes were divided in four groups: 5 (23.8%) patients out of the 21 TS patients which have the 45, X karyotype (group A) also have cryptic Y sequences; none (0%) of the 7 patients who have karyotypes with anomalies on one of the X chromosomes have Y mosaicism (group B); 1 (6.3%) of the 16 patients with a mosaic karyotype have Y material (group C); and 6 (100%) out of 6 patients with a supernumerary marker chromosome (SMC) have Y chromosome sequences (group D). Nine of the 12 patients positive for cryptic Y material were recalled for a repeat study. Following new DNA extraction, molecular analysis was repeated and, in conjunction with fluorescent in situ hybridization (FISH) analysis using the Y centromeric specific probe Yc-2, confirmed the initial positive DNA findings. This study used a reliable and sensitive methodology to identify the presence of Y chromosome material in TS patients thus providing not only a better estimate of a patient's risk in developing either gonadoblastoma or another form of gonadal tumor but also the overall incidence of cryptic Y mosaicism.  相似文献   
4.
Growing evidence suggests that sleep could affect the immunological response after vaccination. The aim of this prospective study was to investigate possible associations between regular sleep disruption and immunity response after vaccination against coronavirus disease 2019 (COVID-19). In total, 592 healthcare workers, with no previous history of COVID-19, from eight major Greek hospitals were enrolled in this study. All subjects underwent two Pfizer–BioNTech messenger ribonucleic acid (mRNA) COVID-19 vaccine BNT162b2 inoculations with an interval of 21 days between the doses. Furthermore, a questionnaire was completed 2 days after each vaccination and clinical characteristics, demographics, sleep duration, and habits were recorded. Blood samples were collected and anti-spike immunoglobulin G antibodies were measured at 20 ± 1 days after the first dose and 21 ± 2 days after the second dose. A total of 544 subjects (30% males), with median (interquartile range [IQR]) age of 46 (38–54) years and body mass index of 24·84 (22.6–28.51) kg/m2 were eligible for the study. The median (IQR) habitual duration of sleep was 6 (6–7) h/night. In all, 283 participants (52%) had a short daytime nap. In 214 (39.3%) participants the Pittsburgh Sleep Quality Index score was >5, with a higher percentage in women (74·3%, p < 0.05). Antibody levels were associated with age (r = −0.178, p < 0.001), poor sleep quality (r = −0.094, p < 0.05), insomnia (r = −0.098, p < 0.05), and nap frequency per week (r = −0.098, p < 0.05), but after adjusting for confounders, only insomnia, gender, and age were independent determinants of antibody levels. It is important to emphasise that insomnia is associated with lower antibody levels against COVID-19 after vaccination.  相似文献   
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Microbiota composition and associated metabolic activities are essential for the education and development of a healthy immune system. Microbial dysbiosis, caused by risk factors such as diet, birth mode, or early infant antimicrobial therapy, is associated with the inception of allergic diseases. In turn, allergic diseases increase the risk for irrational use of antimicrobial therapy. Microbial therapies, such as probiotics, have been studied in the prevention and treatment of allergic diseases, but evidence remains limited due to studies with high heterogeneity, strain-dependent effectiveness, and variable outcome measures. In this review, we sketch the relation of microbiota with allergic diseases, the overuse and rationale for the use of antimicrobial agents in allergic diseases, and current knowledge concerning the use of bacterial products in allergic diseases. We urgently recommend 1) limiting antibiotic therapy in pregnancy and early childhood as a method contributing to the reduction of the allergy epidemic in children and 2) restricting antibiotic therapy in exacerbations and chronic treatment of allergic diseases, mainly concerning asthma and atopic dermatitis. Future research should be aimed at antibiotic stewardship implementation strategies and biomarker-guided therapy, discerning those patients that might benefit from antibiotic therapy.  相似文献   
7.
AIM:To determine end-stage pathologic changes in the liver of septic patients dying in the intensive care unit.
METHODS: Needle liver biopsies obtained immediately after death from 15 consecutive patients with sepsis and no underlying liver disease were subjected to routine histological examination. Liver function tests and clinical monitoring measurements were also recorded.
RESULTS: Liver biochemistries were increased in the majority of patients before death. Histology of liver biopsy specimens showed portal inflammation in 73.3%, centrilobular necrosis in 80%, lobular inflammation in 66.7%, hepatocellular apoptosis in 66.6% and cholangitis/cholangiolitis in 20% of patients. Mixed hepatitic/ cholestatic type of liver injury was observed in 6/15 (40%) patients and hepatitc in 9/15 (60%). Steatosis was observed in 11/15 (73.3%) patients affecting 5%-80% of liver parenchyma. Among the histological features, the presence of portal inflammation in liver biopsy was associated with increased hospitalization in the ICU prior death (P = 0.026).
CONCLUSION: Features of hepatitis and steatosis arethe main histological findings in the liver in the majority of patients dying from sepsis.  相似文献   
8.
Preimplantation genetic diagnosis (PGD) for monogenic disorders currently involves polymerase chain reaction (PCR)-based methods, which must be robust, sensitive and highly accurate, precluding misdiagnosis. Twelve adverse misdiagnoses reported to the ESHRE PGD-Consortium are likely an underestimate. This retrospective study, involving six PGD centres, assessed the validity of PCR-based PGD through reanalysis of untransferred embryos from monogenic-PGD cycles. Data were collected on the genotype concordance at PGD and follow-up from 940 untransferred embryos, including details on the parameters of PGD cycles: category of monogenic disease, embryo morphology, embryo biopsy and genotype assay strategy. To determine the validity of PCR-based PGD, the sensitivity (Se), specificity (Sp) and diagnostic accuracy were calculated. Stratified analyses were also conducted to assess the influence of the parameters above on the validity of PCR-based PGD. The analysis of overall data showed that 93.7% of embryos had been correctly classified at the time of PGD, with Se of 99.2% and Sp of 80.9%. The stratified analyses found that diagnostic accuracy is statistically significantly higher when PGD is performed on two cells versus one cell (P=0.001). Se was significantly higher when multiplex protocols versus singleplex protocols were applied (P=0.005), as well as for PGD applied on cells from good compared with poor morphology embryos (P=0.032). Morphology, however, did not affect diagnostic accuracy. Multiplex PCR-based methods on one cell, are as robust as those on two cells regarding false negative rate, which is the most important criteria for clinical PGD applications. Overall, this study demonstrates the validity, robustness and high diagnostic value of PCR-based PGD.  相似文献   
9.
Marrow cells from patients with higher-risk myelodysplastic syndrome (MDS) exhibit constitutive nuclear factor (NF)-κB activation. The proteasome inhibitor, bortezomib, has limited efficacy as a single agent in acute myeloid leukaemia. Its activity on leukaemic cell lines is potentiated by chemotherapy. We treated 43 higher-risk MDS patients with bortezomib (1·5 mg/m(2) , days 1, 4, 8 and 11) and low dose cytarabine arabinoside (LDAC; 10 mg/m(2) , then 20 mg/m(2) from days 1-14), every 28 d for four cycles. Median follow-up was 29·7 months. Responses were seen in 12 of the 43 patients (28%), including complete response (CR, n = 1), marrow-CR (n = 3), partial response (PR, n = 5) and haematological improvement (HI, n = 3). Responses were seen in 12 (36%) of the 33 previously untreated patients (11% CR, 13% PR, 2·5% HI), compared to none in the 12 previously treated patients (P < 0·01). Responders had better overall survival (median 18·2 vs. 10 months). One CR and 3 marrow-CRs were seen in patients with complex karyotypes. Main toxicity was haematological, responsible for infection in six patients and bleeding in 3. Three patients with Grade 1-2 pre-treatment haematotoxicity developed Grade 3-4 toxicity. Neuropathy was seen in 12% of patients. The addition of bortezomib to LDAC in higher-risk MDS may improve results obtained with LDAC alone, especially in patients with unfavourable karyotypes.  相似文献   
10.

Introduction

Superficial vein thrombosis (SVT) is a common and controversial clinical entity. Recent studies have demonstrated that SVT should be seen as a venous thromboembolism (VTE). The objective of this study was to investigate the prevalence of thrombophilia defects and to estimate the role of age, sex and body mass index (BMI) in patients with varicose veins (VVs) and SVT.

Materials and Methods

A total of 230 patients with VVs, 128 with, and 102 without SVT underwent thrombophilia testing included factor V Leiden, prothrombin G20210A, methylenetetrahydrofolate reductase and plasminogen activator inhibitor- 1 mutations, protein C, protein S (PS), anti-thrombin III and plasminogen deficiencies and levels of A2 antiplasmin, activate protein C resistance and lupus anticoagulant. According to Clinical- Etiology- Anatomy- Pathophysiology (CEAP) classification patients were categorized in two subgroups: moderate disease (C2,3) and severe disease (C4,5,6). Age and body mass index were also assessed.

Results

The prevalence of thrombophilia defects was significantly higher in patients with moderate disease and SVT (p = 0.002). In the C2,3 group, SVT was associated with PS deficiency (p = 0.018), obesity (p < 0.001), male gender (p = 0.047) and age (p < 0.001). There were no significant differences in patients with severe disease.

Conclusions

Age, male sex, obesity and PS deficiency are factors associated with SVT development among patients with VVs having moderate disease (C2,3).  相似文献   
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