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161.
Posttransplantation lymphoproliferative disorders (PTLD) is not uncommon and can occur in 2% to 5% of solid organ recipients on immunosuppression. Epstein-Barr virus (EBV) infection or reactivation and intensive anti-T lymphocyte treatment are important pathogenetic factors for a large proportion of these disorders. Nonclonal lesions with polymorphous histology have a potential for regressing when the immunosuppressants are reduced or stopped. Clonal tumors with a monomorphous histology carry a poor prognosis, and the mortality rate for monoclonal lymphoma has been reported as high as 80%. We report a renal transplant recipient who developed high-grade monoclonal lymphoma only 4 months after a live-donor transplantation. The tumor was EBV positive. Reduction of immunosuppressants resulted in minimal regression of the tumor. The patient was treated with adoptive immunotherapy using ex vivo generation of autologous lymphocyte activated killer (LAK) cells. She had leukapheresis, and autologous peripheral blood mononuclear cells were obtained and cultured in interleukin-2 (IL-2)-rich medium for 9 to 10 days. The IL-2-activated LAK cells were reinfused into the patient without any systemic administration of IL-2. The patient experienced no side effects during the infusion. There was no rejection episode, and the renal function of the patient remained stable after treatment. Computed tomography scan performed 2 months after the infusion showed marked regression of the lesions in the liver and spleen. Five months later, magnetic resonance imaging showed complete resolution of the tumor lesions. Ultrasonography 13 months after the LAK cell infusion showed no lesion. The allograft function was not affected after treatment. Adoptive immunotherapy using IL-2-activated autologous LAK cells was effective in treating this renal transplant patient with EBV-positive high-grade lymphoma. The patient's kidney allograft functioned well without any rejection.  相似文献   
162.
用X晶体衍射测定了氨基醇类抗疟药本芴醇(benflumetolI)的单晶结构,并与已知同类抗疟药金鸡纳生物碱进行了比较。再一次说明了氨基醇类化合物产生抗疟作用的三维空间结构特征。本芴醇的芴环平面与对氯苯基平面的二面角为528°。分子内NO距离为2709A,这一距离与金鸡纳生物碱分子内脂肪氮原子与氧原子之间距离相近。侧链中NCCO的扭转角为476°。本芴醇单晶结构中存在分子内氢键,而未发现分子间氢键,这与以往认为产生抗疟作用的氨基醇类化合物存在分子间氢键而无分子内氢键不同。  相似文献   
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164.
Mild hyperhomocysteinaemia is a major risk factor for vascular disease and neural tube defects (NTDs), conferring an approximately three-fold relative risk for each condition. It has several possible causes: heterozygosity for rare loss of function mutations in the genes for 5,10-methylene tetrahydrofolate reductase (MTHFR) or cystathionine-&bgr;-synthase (CBS); dietary insufficiency of vitamin co-factors B6, B12 or folates; or homozygosity for a common 'thermolabile' mutation in the MTHFR gene which has also been associated with vascular disease and NTDs. We quantified the contribution of the thermolabile mutation to the hyperhomocysteinaemic phenotype in a working male population (625 individuals). Serum folate and vitamin B12 concentrations were also measured and their relationship with homocysteine status and MTHFR genotype assessed. The homozygous thermolabile genotype occurred in 48.4, 35.5, and 23.4% for the top 5, 10 and 20% of individuals repectively) ranked by plasma homocysteine levels, compared with a frequency of 11.5% in the study population as a whole establishing that the mutation is a major determinant of homocystein levels at the upper end of the range. Serum folate concentrations also varied with genotype, being lowest in thermolabile homozygotes. The MTHFR thermolabile genotype should be considered when population studies are designed to determine the effective homocysteine-lowering dose of dietary folate supplements, and when prophylactic doses of folate are recommended for individuals.   相似文献   
165.
In vitro and in vivo persistence of reticulocytes from donor red cells   总被引:1,自引:0,他引:1  
BACKGROUND: Reticulocytes are important in the phenotyping of transfused patients. Reticulocytes can persist in blood units for the shelf life of the unit. STUDY DESIGN AND METHODS: Temperature dependence of reticulocyte persistence was examined in vitro at 4, 24, and 37 degrees C by using thiazole orange staining and flow cytometric analysis. Two-color flow cytometric analysis was used to evaluate the persistence of donor reticulocytes in transfused patients. RESULTS: Flow cytometric analysis using thiazole orange demonstrated that persistence of reticulocytes in units of stored CPDA-1 blood was temperature-dependent. Reticulocytes disappeared over 13 and 6 days at 24 degrees C and 37 degrees C, respectively, but at 4 degrees C the reticulocyte count changed little over 35 days. Two-color flow cytometric analysis of reticulocyte antigens was used to follow donor reticulocytes in 14 transfusion events in nine different patients. Donor reticulocytes persisted through 24 hours in 75 percent of the patients and were detectable at 48 hours in three patients. CONCLUSION: This study demonstrates that reticulocytes persist during refrigerated storage; they are detectable in the circulation of most recipients for the first 24 hours after transfusion and in the circulation of a few recipients after 48 hours. These findings may have relevance for separation techniques based on reticulocyte density in samples drawn shortly after transfusion and for evaluation of reticulocyte counts in patients with hematologic abnormalities.  相似文献   
166.
We investigated 112 patients [mean age 39.5 +/- 10.5 years, 59% women (n=66)] with chronic posttraumatic headache following cranio-cervical acceleration/deceleration trauma after an average time interval of 2.5 +/- 1.9 years from trauma. Headache following minor head injury or whiplash is one of the most prominent problems in neurotraumatology. Previous research is inconclusive regarding the symptomatic approach of this type of headache. Details of the phenomenology of posttraumatic headache in the previous literature are inconclusive. This may lead to inappropriate treatment strategies, because recent advances in therapy of different headache types may be neglected. Patients were investigated at the outpatient service of the Department of Psychiatry. Headache was analyzed according to its principal location, laterality, projection, quality, precipitation or aggravation and possible additional symptoms. For this analysis, headache was diagnosed according to the classification of the International Headache Society. The results showed that 42 patients (37%) had tension-type headache, 30 (27%) were identified as suffering from migraine, whereas 20 patients (18%) had cervicogenic headache. An additional 18% of patients suffered from headache that did not fulfill criteria of a particular category. In 104 patients (93%), neck pain was associated in time with headache. Each of the diagnosed headache types in this study may require specific treatment strategies based upon empirical studies of non-traumatic headache types. For these reasons a detailed analysis of headache following cranio-cervical acceleration/deceleration trauma is necessary.  相似文献   
167.
    
Mesonephric-like adenocarcinoma (MLA) of the female genital tract is an uncommon histotype that can arise in both the endometrium and the ovary. The exact cell of origin and histogenesis currently remain unknown. Here, we investigated whole genome DNA methylation patterns and copy number variations (CNVs) in a series of MLAs in the context of a large cohort of various gynaecological carcinoma types. CNV analysis of 19 MLAs uncovered gains of chromosomes 1q (18/19, 95%), 10 (15/19, 79%), 12 (14/19, 74%), and 2 (10/19, 53%), as well as loss of chromosome 1p (7/19, 37%). Gains of chromosomes 1q, 10, and 12 were also identified in the majority of mesonephric adenocarcinomas of the uterine cervix (MAs) as well as subsets of endometrioid carcinomas (ECs) and low-grade serous carcinomas of the ovary (LGSCs) but only in a minority of serous carcinomas of the uterine corpus (USCs), clear cell carcinomas (CCCs), and tubo-ovarian high-grade serous carcinomas (HGSCs). While losses of chromosome 1p together with gains of chromosome 1q were also identified in both MA and LGSC, gains of chromosome 2 were almost exclusively identified in MLA and MA. Unsupervised hierarchical clustering and t-SNE analysis of DNA methylation data (Illumina EPIC array) identified a co-clustering for MLAs and MAs, which was distinct from clusters of ECs, USCs, CCCs, LGSCs, and HGSCs. Group-wise comparisons confirmed a close epigenetic relationship between MLA and MA. These findings, in conjunction with the established histological and immunophenotypical overlap, suggest bona fide mesonephric differentiation, and support a more precise terminology of mesonephric-type adenocarcinoma instead of MLA in these tumours. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.  相似文献   
168.
    
INTRODUCTIONThe obesity paradox, where obesity is associated with improved survival, has been described in patients undergoing haemodialysis and in those with heart failure. It was also demonstrated in patients undergoing valve replacement for aortic stenosis (AS). We explored this phenomenon in medically managed severe AS.METHODS154 patients with medically managed severe AS (aortic valve area index [AVAi] < 0.6 cm2/m2; mean pressure gradient > 40 mmHg and peak velocity > 400 cm/s) and preserved left ventricular ejection fraction (> 50%) were categorised into the obese (body mass index [BMI] Asian cut-off ≥ 27.5 kg/m2) and non-obese groups. Their clinical and echocardiographic profiles were compared.RESULTS24 (15.6%) patients were obese. Obese patients were similar to non-obese patients in age (68.5 ± 11.6 years vs. 68.9 ± 13.1 years) but had higher prevalence of cardiovascular risk factors. Left atrial diameter (43.7 ± 6.7 mm vs. 38.5 ± 10.2 mm) was larger in obese patients, while left ventricular outflow tract diameter (19.5 ± 1.7 mm vs. 20.4 ± 2.1 mm) was smaller. Despite lower AVAi in obese patients (0.36 ± 0.10 cm2/m2 vs. 0.43 ± 0.11 cm2/m2), there was lower mortality (37.5% vs. 41.0%, log-rank 4.06, p = 0.045) on follow-up (8.0 ± 5.7 years). After adjusting for age and AVAi, higher BMI ≥ 27.5 kg/m2 remained protective for mortality (hazard ratio 0.38, 95% confidence interval 0.15 to 0.98, p = 0.046).CONCLUSIONWe demonstrated that obesity was associated with improved survival in severe AS despite lower AVAi and increased prevalence of cardiovascular risk factors.  相似文献   
169.
    
Recently a novel subtype of endometrial stromal sarcoma (ESS) defined by recurrent genomic alterations involving BCOR has been described (HGESS‐BCOR). We identified a case of HGESS‐BCOR with a ZC3H7B‐BCOR gene fusion, which harbored an amplification of the MDM2 locus. This index case prompted us to investigate MDM2 amplification in four additional cases of HGESS‐BCOR. Tumors were analyzed for MDM2 amplification by array‐based profiling of copy number alterations (CNAs) and fluorescence in situ hybridization (FISH), as well as for MDM2 expression by immunohistochemistry (IHC). Additionally, a cohort of other mesenchymal uterine neoplasms, including 17 low‐grade ESS, 6 classical high‐grade ESS with YWHAE‐rearrangement, 16 uterine tumors resembling ovarian sex cord tumors, 7 uterine leiomyomas and 8 uterine leiomyosarcomas, was analyzed for CNAs in MDM2. Copy number profiling identified amplification of the 12q15 region involving the MDM2 locus in all five HGESS‐BCOR. Subsequent validation analyses of three tumors confirmed MDM2 amplification using MDM2 FISH. Accordingly, IHC showed MDM2 overexpression in all analyzed cases. None of the other uterine neoplasms in our series, including tumors that are in the histopathological differential diagnoses of HGESS‐BCOR, showed copy number gains of MDM2. Together, our results indicate that HGESS‐BCOR carries MDM2 amplifications, which has diagnostic implications and could potentially be used for targeted therapies in these clinically aggressive tumors.  相似文献   
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