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Geriatric cancer patients present special challenges for clinicians. Few large series have been published in the last 20 years on the types of neoplasms that involve the central nervous system (CNS) in older individuals. To review types of neoplasms involving the central CNS that are currently being encountered by pathologists and neurosurgeons, we identified from our databases for the years 1992-2002, inclusive, patients 75 years or older who had symptomatic lesions requiring neurosurgical interventions. Retrospective characterization of tumors by immunohistochemistry, in situ hybridization, and fluorescence in situ hybridization was performed whenever possible and relevant to tumor type. Neurosurgical procedures (n=125) on 119 patients were identified; 90 patients were diagnosed as having neoplasms, with clot evacuation or infections being the most frequent non-neoplastic conditions necessitating surgery. Tumor types included glioblastomas (36 patients), meningiomas (16), pituitary adenomas (12), lymphomas or other hematological malignancies (8), anaplastic gliomas (5), metastases (6), head and neck malignancies with direct intracranial extension (3), and other miscellaneous tumor types (4). Compared with older literature series, we encountered a larger number of elderly patients with CNS lymphomas and fewer who came to surgery for CNS metastatic disease. In the "older old", glioblastomas are the most frequent symptomatic tumors necessitating surgical intervention. Glioblastomas in this aged cohort display the signature features of the small cell phenotype (62%), high cell cycle labeling indices (mean MIB-1-labeling index=25.1%), and either amplification of epidermal growth factor receptor or gain of chromosome 7 by fluorescence in situ hybridization (93% of assessable cases).  相似文献   
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Congenital nephrogenic diabetes insipidus (NDI) is a rare disease caused most often by mutations in the vasopressin V2 receptor (AVPR2). We studied a family which included a female patient with NDI with symptoms dating from infancy. The patient responded to large doses of desmopressin (dDAVP) which decreased urine volume from 10 to 4 I/day. Neither the parents nor the three sisters were polyuric. The patient was found to be a compound heterozygote for two novel recessive point mutations in the aquaporin-2 (AQP2) gene: L22V in exon 1 and C181W in exon 3. Residue Cys181 in AQP2 is the site for inhibition of water permeation by mercurial compounds and is located near to the NPA motif conserved in all aquaporins. Osmotic water permeability (Pf) in Xenopus oocytes injected with cRNA encoding C181W-AQP2 was not increased over water control, while expression of L22V cRNA increased the Pf to approximately 60% of that for wild-type AQP2. Co-injection of the mutant cRNAs with the wild-type cRNA did not affect the function of the wild-type AQP2. Immunolocalization of AQP2-transfected CHO cells showed that the C181W mutant had an endoplasmic reticulum-like intracellular distribution, whereas L22V and wild-type AQP2 showed endosome and plasma membrane staining. Water permeability assays showed a high Pf in cells expressing wild-type and L22V AQP2. This study indicates that AQP2 mutations can confer partially responsive NDI.   相似文献   
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A 22-year-old man with malignant immunoblastic lymphoma had "locked-in" syndrome within 48 hours of receiving a single (100 mg) dose of intrathecal cytosine arabinoside (ara-C) in conjunction with intravenous ara-C, cisplatin, and doxorubicin. Eight hours after therapy, the patient had central hypoventilation and blurred vision that progressed to blindness within 3 hours. During the next 10 hours, he became completely quadriplegic but remained intermittently alert and was able to respond to commands by eye or head movements. Radiographic studies showed necrosis of the medulla and swelling of the entire spinal cord. The patient persisted in a locked-in state until his death 3 weeks later, after removal of life support systems. Autopsy confirmed extensive necrosis of the lower medulla, optic chiasm, cranial nerves I and IV, and spinal cord. This case was unusual for its severity. The temporal relationship to ara-C instillation favors a toxic idiosyncratic response to chemotherapy. The authors advocate caution when bolus intrathecal and intravenous ara-C are administered to a patient within a short time of each other.  相似文献   
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AIM:To investigate if the presence of relevant genetic polymorphisms has effect on the effectual clearance of bacteria by monocytes and granulocytes in patients with Crohn’s disease(CD).METHODS:In this study,we assessed the differential responses in phagocytosis by measuring the phagocytic activity and the percentage of active phagocytic monocytes and granulocytes in inflammatory bowel disease patients as well as healthy controls.As both autophagy related like 1(ATG16L1)and immunityrelated guanosine triphosphatase gene are autophagy genes associated with CD and more recently nucleo-tide-binding ligomerization domain-containing protein2(NOD2)has been identified as a potent inducer of autophagy we genotyped the patients for these variants and correlated this to the phagocytic reaction.The genotyping was done with restriction fragment length polymorphisms analysis and the phagocytosis was determined with the pHrodo?Escherichia coli Bioparticles Phagocytosis kit for flowcytometry.RESULTS:In this study,we demonstrate that analysis of the monocyte and granulocyte populations of patients with CD and ulcerative colitis showed a comparable phagocytic activity(ratio of mean fluorescence intensity)between the patient groups and the healthy controls.CD patients show a significantly higher phagocytic capacity(ratio mean percentage of phagocytic cells)compared to healthy controls(51.91%±2.85%vs 37.67%±7.06%,P=0.05).The extend of disease was not of influence.However,variants of ATG16L1(WT:2.03±0.19 vs homozygoot variant:4.38±0.37,P<0.009)as well as NOD2(C-ins)(heterozygous variant:42.08±2.94 vs homozygous variant:75.58±4.34(P=0.05)are associated with the phagocytic activity in patients with CD.CONCLUSION:Monocytes of CD patients show enhanced phagocytosis associated with the presence of ATG16L1 and NOD2 variants.This could be part of the pathophysiological mechanism resulting in the disease.  相似文献   
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The aim of this study is to assess the efficacy of microwave irradiation in disinfecting gypsum casts and also to compare its efficacy with validated method of chemical disinfection. The present study is an ex vivo study conducted on a sample of five irreversible hydrocolloid impressions in vitro and on ten patients gypsum casts in vivo following standard impression techniques to check the efficacy of microwave oven irradiation and compare its efficacy with standard chemical method of disinfection. Results were analysed using Mann–Whitney test and Wilcoxon signed rank test. Untreated gypsum casts showed cfu/ml counts with a median log value of 6, while microwave-irradiated ones had median cfu/ml counts of 0. Casts poured from chemically disinfected impressions demonstrated cfu/ml counts with a median log value of 5. Microwave irradiation was found to be effective in disinfecting gypsum casts when compared to chemical disinfectant in disinfecting dental impressions.  相似文献   
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Summary Previous investigations by our group demonstrated the efficacy of single source allogeneic cytotoxic T lymphocytes (CTLs) given multiple times in reducing or curing tumor burden in the rat 9L gliosarcoma model. In this study, the lack of toxicity to normal brain when single source allogeneic CTLs were intracranially administered multiple times is documented. Additionally, the efficacy and lack of toxicity of allogeneic CTLs from multiple sources, each given once is documented. CTLs sensitized to Fischer antigen were prepared from major histocompatibility complex incompatible DA, PVG, Sprague-Dawley and Wistar-Furth rat lymphocytes. CTLs from multiple donors were administered one time each to Fischer rats bearing established 9L tumor at staggered intervals over a two week period and survival was monitored in relation to a sham treated group. Additional groups of nontumor-bearing rats received either multiple source allogeneic CTLs or single source DA anti Fischer CTLs in the same treatment regimen. Histological evaluation of the nontumor-bearing brains receiving either single or multiple source allogeneic CTL infusions showed minimal localized brain damage confined to the cannulation tract. No neuronal loss or inflammatory reaction was seen either adjacent to or remote from the administration site. Brains from the long-term survivors of the tumor-bearing animals showed no residual neoplasm; the instillation site had focal sterile abscesses; gliosis and neuronal loss did not extend into adjacent brain. The safety and potential of chronic, local allogeneic CTL administration, derived from multiple donors, as adjuvant local therapy for brain tumors was demonstrated.  相似文献   
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The authors report a 57-year-old man who survived 18 days after swallowing an 8-oz. can of Sterno in a suicide attempt. Two days after ingestion, he developed confusion and acute renal failure requiring hemodialysis, followed on day 8 by a delayed but rapidly evolving ascending paralysis. Pathologic examination showed severe demyelination, with lesser axonal damage, of virtually all cranial and peripheral nerves sampled and sparing of central myelin. The diethylene glycol in the Sterno was considered responsible for this intoxication.  相似文献   
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