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31.
In 2-8% of patients with mental retardation, small copy number changes in the subtelomeric region are thought to be the underlying cause. As detection of these genomic rearrangements is labour intensive using FISH, we constructed and validated a high-density BAC/PAC array covering the first 5 Mb of all subtelomeric regions and applied it in our routine screening of patients with idiopathic mental retardation for submicroscopic telomeric rearrangements. The present study shows the efficiency of this comprehensive subtelomere array in detecting terminal deletions and duplications but also small interstitial subtelomeric rearrangements, starting from small amounts of DNA. With our array, the size of the affected segments, at least those smaller than 5 Mb, can be determined simultaneously in the same experiment. In the first 100 patient samples analysed in our diagnostic practice by the use of this comprehensive telomere array, we found three patients with deletions in 3p, 10q and 15q, respectively, four patients with duplications in 9p, 12p, 21q and Xp, respectively, and one patient with a del 6q/dup 16q. The patients with del 3p and 10q and dup 12p had interstitial rearrangements that would have been missed with techniques using one probe per subtelomeric region chosen close to the telomere.  相似文献   
32.
 Renal cell carcinomas belong to the small group of tumors that are able to induce antitumor responses. Here we describe two general types of cytotoxic effector lymphocytes that can eliminate autologous tumor cells and discuss the role that major histocompatibility complex encoded molecules play in governing their specificities. Improved understanding of the cellular and molecular basis of renal cell carcinoma recognition opens new avenues of research with the potential to develop better immunotherapies for patients with metastatic disease. Received: 24 July 1996 / Accepted: 1 November 1996  相似文献   
33.
The loomotor activity of male mice (Mus musculus) was monitored by infrared photoelectric beams under three lighting regimens: LD (12 h of light and 12 h of dark), DD (constant dark), and LL (constant broad-spectrum light, 10 lux). Circadian period of locomotor activioty (τ) was compared among 3 inbred strains of mice, C57BL/6J (B6), BALB/c (C), and DBA/2J (D2), and 26 recombinant inbred strains B×D (B6×D2). the τ under both continuous low-intensity light and continuous darkenss varied significantly among strains. Under DD the mean τ was 23.8 h for B6, 23.7 h for D2, and 23.6 h for C. Under LL the mean τ was 25.1 for B6, 23.9 h for D2, and 25.5 h for C. Frequency histograms of the mean τ of 26B×D RI mouse strains (three to seven animals per strain) in either DD or LL and the difference between them, Δτ, had distributions which appeared unimodal, suggesting polygenic inheritances. The narrow-sense heritability determined using 26 strains of B×D RI mice was about 55% for τ and about 38% for both τ in LL and Δτ. An estimated four loci contribute to the variance of τ in constant darkness and five to the variance of τ in constant low-intensity light among the strains studied. Quantitative trait locus (QTL) analysis identified several potential genetic loci associated with τ in constant darkness, τ in constant low-intensity light, and Δτ. The associations of highest probability for each of these traits were theD1Nds4 locus (p<0.001) on mouse chromosome 1, theD5Ncvs52 locus (p<.05) on mouse chromosome 5, and thePmv12 locus (p<.01) at 70 cM on mouse chromosome 5, respectively. A QTL identified for τ was associated (p<.05) with theD2NDS1 marker at 45 cM on chromsome 2 near the Ea 6 marker at 46 cM associated (p<.05) with that reported for the period of wheel running activity in seven C×B RI strains (Schwartz, W. J., and Zimmerman, P.,J. Neurosci. 10:3685 1990).  相似文献   
34.
Disseminated infection with the coelomycetous fungus Nattrassia mangiferae is a very rare disease affecting only the immunocompromised host. We report the first case of a disseminated infection with spondylodiscitis and granular skin lesions due to N. mangiferae in a renal transplant patient.  相似文献   
35.
Chlamydia trachomatis (CT) as well as Chlamydophila pneumoniae (CP) cause chronic inflammatory diseases in humans. Persistently infected monocytes are involved in the pathogenesis by inducing mediators of inflammation. An in vitro system of chlamydial persistence in human peripheral blood monocytes (HPBM) was used to investigate prostaglandin E(2) (PGE(2)) production and the expression of the key enzyme for prostaglandin production, cyclooxygenase-2 (COX-2). PGE(2) production was determined by PGE(2)-ELISA of HPBM-culture supernatants. Cox-2 mRNA expression was measured by real-time RT-PCR of total RNA isolated from HPBM. Both, CT and CP, stimulated PGE(2) production of HPBM in vitro. Equivalent numbers of CT per host cell induced a higher PGE(2)-response compared to CP. The amount of synthesized PGE(2) depended on the chlamydial multiplicity of infection (MOI). Even at an MOI of 10 the amount of CT- and CP-induced prostaglandin, respectively, was lower than the amount of prostaglandin induced by E. coli lipopolysaccharide (LPS) at a concentration of 10microg/ml. In contrast to stimulation with LPS, Chlamydia-induced PGE(2) production as well as cox-2 mRNA decreased after day 1 post infection (p.i.). These data indicate that Chlamydia stimulate PGE(2) production in human monocytes. Since Chlamydia are often contaminated by mycoplasma, the influence of mycoplasma on the prostaglandin production was investigated additionally. Mycoplasma fermentans (MF) also stimulated PGE(2) production. The co-infection of mycoplasma and Chlamydia resulted in an additive effect in the production of PGE(2). Thus it is important to use host cells and Chlamydia free of mycoplasma contamination for the analysis of Chlamydia-induced prostaglandin production.  相似文献   
36.
The OPA1 gene, encoding a dynamin-related GTPase that plays a role in mitochondrial biogenesis, is implicated in most cases of autosomal dominant optic atrophy (ADOA). Sixty-nine pathogenic OPA1 mutations have been reported so far. Most of these are truncating mutations located in the GTPase domain coding region (exons 8-16) and at the 3'-end (exons 27-28). We screened 44 patients with typical ADOA using PCR-sequencing. We also tested 20 sporadic cases of bilateral optic atrophy compatible with ADOA. Of the 18 OPA1 mutations found, 14 have never been previously reported. The novel mutations include one nonsense mutation, 3 missense mutations, 6 deletions, one insertion and 3 exon-skipping mutations. Two of these are de novo mutations, which were found in 2 patients with sporadic optic atrophy. The recurrent c.2708_2711delTTAG mutation was found in 2 patients with a severe congenital presentation of the disease. These results suggest that screening for OPA1 gene mutations may be useful for patients with optic atrophy who have no affected relatives, or when the presentation of the disease is atypical as in the case of early onset optic atrophy.  相似文献   
37.
Brain abscess. A study of 45 consecutive cases   总被引:9,自引:0,他引:9  
Clinical features, findings of diagnostic studies, results of therapy, and prognostic factors were analyzed in 45 patients with brain abscesses. The number of patients diagnosed yearly has increased since CT scanning became available, but despite the enhanced sensitivity, the time from either onset of symptoms or hospital admission until initiation of therapy was not decreased and there was no dramatic effect upon morbidity or mortality in this series. Infections of paranasal sinuses, ears, lungs, and odontogenic foci were predisposing factors in approximately 70% of cases. Single abscesses, present in 75% of patients, were distributed equally in both hemispheres, with more than half in the frontal and parietal lobes. Common signs and symptoms included headache, fever, chills, seizures, nausea, vomiting, altered sensorium, nuchal rigidity, and localizing neurologic signs. Blood cultures were positive in 11%. Lumbar puncture rarely provided data from which a diagnosis could be established; CSF cultures were positive in only 7% of patients, and there was a 15% temporally associated incidence of brain herniation and death. Diagnostic information was most readily obtained using imaging techniques such as CT and 99mTc scanning, and arteriography was invasive and of no added value. CT scans are however, often initially negative in patients presenting with clinical signs of meningitis presumably following rupture of an abscess into the subarachnoid space, and the average time for changes to appear on CT scan is 9 days. It is, therefore, recommended that when the clinical assessment suggests the possibility of brain abscess the patient be treated empirically with antibiotics and that lumbar puncture be performed only after thoughtful assessment of the risk-to-benefit ratio for each patient. Causative organisms were isolated from more than 80% of abscesses despite prior antibiotic treatment; more than half grew a single pathogen, most commonly streptococci. Anaerobic and microaerophilic bacteria accounted for 62% of all isolates, and were the only organisms in 33% of patients. Computerized tomographic scans in 30 patients showed "ring-enhancing" lesions, nodular enhancement, or areas of low attenuation. Complete resolution of abscesses on CT scans rarely occurred during hospitalization and took as long as 5 months. Decrease in the size of abscesses on CT scan correlated well with clinical improvement and was seen within a week when abscesses were excised, but was often not obvious for 6 to 8 weeks if antibiotics were used alone.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
38.
Epstein–Barr virus (EBV) reactivation is a very common and potentially lethal complication of renal transplantation. However, its risk factors and effects on transplant outcome are not well known. Here, we have analysed a large, multi-centre cohort (N = 512) in which 18.4% of the patients experienced EBV reactivation during the first post-transplant year. The patients were characterized pre-transplant and two weeks post-transplant by a multi-level biomarker panel. EBV reactivation was episodic for most patients, only 12 patients showed prolonged viraemia for over four months. Pre-transplant EBV shedding and male sex were associated with significantly increased incidence of post-transplant EBV reactivation. Importantly, we also identified a significant association of post-transplant EBV with acute rejection and with decreased haemoglobin levels. No further severe complications associated with EBV, either episodic or chronic, could be detected. Our data suggest that despite relatively frequent EBV reactivation, it had no association with serious complications during the first post-transplantation year. EBV shedding prior to transplantation could be employed as biomarkers for personalized immunosuppressive therapy. In summary, our results support the employed immunosuppressive regimes as relatively safe with regard to EBV. However, long-term studies are paramount to support these conclusions.  相似文献   
39.
Quality of Life Research - The Adult Social Care Outcomes Toolkit for informal carers (ASCOT-Carer) can be used to assess long-term care-related quality of life (LTC-QoL) of adult informal carers...  相似文献   
40.
Quality of Life Research - The Adult Social Care Outcomes Toolkit for Carers (ASCOT-Carer), developed in England, measures the effects of long-term care (LTC) services and carer support on informal...  相似文献   
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