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991.
AIMS: To analyse the clinicopathological features of synovial sarcoma presenting in patients over 60 years of age, an uncommon subset which have not been specifically studied. METHODS AND RESULTS: Thirty-two cases of primary synovial sarcoma in patients aged > or =60 years were retrieved from the authors' consultation files. These were analysed histologically and immunohistochemically and clinical follow-up was obtained in 26 cases (median duration 41 months). Mean age at diagnosis was 71.6 years (range 60-84) with 19 females and 13 males. Anatomical sites were lower limb (n = 13), upper limb (n = 5), lung/pleura (n = 5), trunk (n = 4), head/neck (n = 3), mediastinum (n = 1) and scrotum (n = 1). Histologically, 23 were monophasic and nine were biphasic; 14 were poorly differentiated, of which five showed focally marked pleomorphism. Unusual features in two cases each included organoid nodules, granular cell change, squamous metaplasia and papillary architecture. Ten patients developed local recurrence and 11 developed metastases, of whom seven died. Large tumour size, poorly differentiated morphology and high mitotic rate correlated with poor outcome. CONCLUSIONS: Less than 10% of synovial sarcomas occur in patients over 60, in which age group this diagnosis is often not considered. Despite inevitable bias in consultation material, it seems that these cases, when compared with younger age groups, more often show poorly differentiated histology and more often develop at unusual locations.  相似文献   
992.
The primary esophageal lymphoma is extremely rare, and shows various morphologic characteristics. Only a single case of mucosa-associated lymphoid tissue (MALT) type lymphoma confined to the esophagus has been reported in the literature. A 61-yr-old man was referred to our hospital for evaluation of an esophageal submucosal tumor (SMT) that had been detected incidentally by endoscopy. He had a history of pulmonary tuberculosis with long-term anti-tuberculosis medication 15 yr before, and also had a history of syphilis, which had been treated one year before. He had been taking a synthetic thyroid hormones for the past 10 months because of an autoimmune thyroiditis. Endoscopy showed a longitudinal round and tubular shaped smooth elevated lesion, which was covered with intact mucosa and located at the mid to distal esophagus, 31 cm to 39 cm from the incisor teeth. Endoscopic ultrasonography (EUS) showed a huge longitudinal growing intermediate- to hypo-echoic mass located in the submucosal layer with internal small, various sized honeycomb-like anechoic lesions suggesting germinal centers. Subsequently, he underwent a surgery, which confirmed the mass as a primary esophageal low-grade B-cell lymphoma of MALT type.  相似文献   
993.
Mollaret's meningitis (MM) is a rare disease of benign nature characterized by recurrent episodes of aseptic meningitis. Cerebrospinal fluid (CSF) examination remains the sole diagnostic modality. Eighteen CSF samples from 14 patients were studied along with the clinical data. Specimens were prepared by cytocentrifugation and Millipore filtration and were stained with Diff-Quik and Papanicolaou stains. Eight patients were men and six were women, with an age range of 17-74 yr (mean age 37 yr). Most common clinical presentation was recurrent episodes of headaches and photophobia followed by a sustained mild fever lasting 5-7 days. The CSF showed markedly increased cellularity with pleocytosis. The differential count showed predominant monocytosis ranging from 84% to 100% (mean 96). In our series, two patients had herpes simplex virus type 2 (HSV-2) DNA detected by polymerase chain reaction (PCR) in the CSF. The monocytes were seen predominantly singly, but three cases showed a strong tendency to aggregate in small groups. Phenotypically, these cells had bean-shaped bilobed nuclei as well as multiple deep nuclear clefts depicting the so-called "footprint" appearance. In four cases, multiple blunt-tipped cytoplasmic pseudopods were noted. Degenerated monocytes with the appearance of the so-called "ghost cells" were noted in one-half of the cases. Background cells were mostly small mature lymphocytes; however, one-half of cases showed a significant amount of plasma cells and/or polymorphonuclear leukocytes (PMNs). Lysed blood with hemosiderin-laden macrophages and numerous leptomeningeal cells were seen in two cases. CSF examination of MM presents a spectrum of cytomorphologic features. When interpreted in light of the appropriate clinical setting. the latter, although nonspecific, provides an accurate diagnosis. The differential diagnosis includes various degenerative, inflammatory/infectious, and lymphoproliferative disorders of the central nervous system.  相似文献   
994.
Optimal T-cell activation requires both an antigen-specific and a costimulatory signal. The outcome of T-cell activation can be influenced by the nature of the costimulatory signal the T cell receives. We recently demonstrated the ability of stimulation through intercellular adhesion molecule-1 (ICAM-1), resident on the T-cell surface, to provide a second signal for T-cell activation, and have extended that work here to begin an examination of the functional outcome of this set of signals. Costimulation through ICAM-1 resulted in a greater percentage of cells having undergone more than three divisions when compared to costimulation through leucocyte function-associated antigen-1 (LFA-1). Costimulation through ICAM-1 also had an effect similar to costimulation through CD28 in its ability to down-regulate the cyclin dependent kinase inhibitor p27kip1. Costimulation through ICAM-1 provided greater protection from apoptosis than costimulation through LFA-1, especially in cells having divided more than three times. This was supported by the ability of costimulation through ICAM-1 to up-regulate the anti-apoptotic protein Bcl-2. Finally, costimulation through ICAM-1 or CD28 produced a greater number of T cells with a memory phenotype than costimulation through LFA-1.  相似文献   
995.
目的探讨丹参对小鼠冻融卵巢同种异体移植后的血管化作用及可能机制。方法收集C57BL/6j雌鼠和BALB/c雄鼠杂交的F1代4周龄小鼠卵巢,慢速冻融后移植至B6C2F1代8~12周龄雄鼠的肾被膜下,移植后小鼠按给药不同分为生理盐水组和丹参组,分别于移植后1d(24h)、2d(48h)和7d回收移植物,将冻融以及移植后不同时间段的卵巢组织进行HE染色全卵巢卵泡计数,免疫组织化学及RT-PCR方法检测血管相关蛋白及基因的表达。结果移植卵巢组织各时间段全卵巢卵泡计数及卵泡存活率丹参组均高于生理盐水对照组(P0.05);移植后小鼠血管内皮生长因子(VEGF)的表达有上升趋势,第7天达最高峰,两组之间无显著性差异(P0.05);移植卵巢组织各时间段细胞凋亡指数,丹参组均低于生理盐水对照组(P0.05);移植后48h丹参组VEGF188mRNA和VEGF164mRNA的表达量较对照组高,两组之间有显著性差异(P0.05)。结论小鼠卵巢组织移植后早期阶段丹参能促进卵泡发育,减少卵泡凋亡,可能与提高移植卵巢组织内血管相关基因VEGF(主要是VEGF164mRNA和VEGF188mRNA)的表达而促进移植后早期血管化有关。  相似文献   
996.
997.
Population‐specific epidemiological data on human papillomavirus (HPV) infection are essential for formulating strategies to prevent cervical cancer. The age‐specific prevalence of HPV infection was determined among 1,600 women enrolled for cervical screening in Macao. A U‐shaped age‐specific prevalence curve with a first peak (prevalence rate, 10%) at 20–25 years and a second peak (13%) at 51–55 years was observed. Co‐infections with multiple types were detected in 32.5% of HPV‐positive subjects and without significant variation among different age groups (P = 0.318). The majority (84.6%) of the positive samples harbored high‐ or probable high‐risk HPV types, and these types also exhibited a similar U‐shaped age‐specific prevalence curve. In contrast, low and unknown‐risk HPV types remained at a low prevalence (1.5–2.5%) throughout the age groups between 20 and 50 years, and with a small peak (4.5%) at 51–55 years. HPV 52 was the most common type found in 26.8% of positive samples, followed by HPV 16 (15.5%), HPV 68 (11.4%), HPV 18 and HPV 58 (8.9% each), HPV 54 (8.1%), HPV 53 (7.3%), HPV 39 (6.5%), HPV 33 and HPV 66 (5.7% each). In conclusion, because of the early peak of infection, vaccination and educational campaigns in Macao should start early and target at teenagers. The presence of a second peak containing mainly high‐risk HPV types in older women indicates the need to evaluate the cover of the cervical screening programme for older women. Further study to determine the contribution of HPV 52 in high‐grade cervical neoplasia and invasive cancers in Macao is warranted. J. Med. Virol. 82:1724–1729, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
998.
Cell-free fetal DNA is present in the plasma of pregnant women. It consists of short DNA fragments among primarily maternally derived DNA fragments. We sequenced a maternal plasma DNA sample at up to 65-fold genomic coverage. We showed that the entire fetal and maternal genomes were represented in maternal plasma at a constant relative proportion. Plasma DNA molecules showed a predictable fragmentation pattern reminiscent of nuclease-cleaved nucleosomes, with the fetal DNA showing a reduction in a 166-base pair (bp) peak relative to a 143-bp peak, when compared with maternal DNA. We constructed a genome-wide genetic map and determined the mutational status of the fetus from the maternal plasma DNA sequences and from information about the paternal genotype and maternal haplotype. Our study suggests the feasibility of using genome-wide scanning to diagnose fetal genetic disorders prenatally in a noninvasive way.  相似文献   
999.

Introduction

X-linked agammagobulinemia (XLA) is a primary immunodeficiency disorder caused by Bruton's tyrosine kinase (Btk) gene mutation. Recent studies suggested genotype-phenotype correlation in XLA, but a definitive association remains controversial.

Patients and Methods

We examined the relationship between specific Btk gene mutations and severity of clinical presentation in 62 patients with XLA. Disease severity was assessed by the age of disease onset and the presence of severe infections, while mutations were classified into severe and mild based on structural and functional consequence by bioinformatics analysis.

Results

Fifty-six Btk mutations were identified in 62 patients from 57 kindreds. Variation in phenotypes was observed, and there was a tendency of association between genotype and age of disease onset as well as occurrence of severe infections.

Conclusion

A critical analysis of the circumstances upon presentation also revealed that under-recognition of recurrent infections and relevant family history are important hurdles to timely diagnosis of XLA.  相似文献   
1000.
Cholera caused by the O139 serogroup still remains a public health concern in certain regions of the world and the existing O1 vaccines do not cross-protect cholera caused by this serogroup. An aminolevulinic acid (ALA) auxotroph vaccine candidate against the O139 serogroup, designated as VCUSM2, was recently developed. It was found to be immunogenic in animal model studies but showed mild reactogenic effects due to the presence of two intact copies of Vibrio cholerae toxin (CTX) genetic element. In the present study we have modified the ctx operon by systematic allelic replacement methodology to produce a mutant strain, designated as VCUSM14. This strain has two copies of chromosomally integrated and mutated ctxA gene, encoding immunogenic but not toxic cholera toxin A subunit (CT-A). The amino acids arginine and glutamic acid at position 7th and 112th, respectively, in CT-A of VCUSM14 were substituted with lysine (R7K) and glutamine (E112Q), respectively. Two copies of the ace and zot genes present in the ctx operon were also deleted. Cholera toxin-ELISA using GM1 ganglioside showed that the both wild type CT and mutated CT were recognized by anti-CT polyclonal antibodies. VCUSM14 produced comparatively less amount of antigenic cholera toxin when compared to the VCUSM2 and Bengal wild type strain. VCUSM14 did not elicit fluid accumulation when inoculated into rabbit ileal loops at doses of 106 and 108 CFU. The colonization efficiency of VCUSM14 was one log lower than the parent strain, VCUSM2, which can be attributed to the ALA auxotrophy and less invasive properties of VCUSM14. VCUSM14, thus a non-reactogenic auxotrophic vaccine candidate against infection by O139 V. cholerae.  相似文献   
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