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51.
A case of synchronous squamous cell carcinomas in the soft palate,larynx and esophagus is reported, along with findings of molecular-pathologicalanalysis. A biopsy sample from the aryngeal carcinoma revealedwell differentiated squamous cell carcinoma harboring two pointmutations at codons 144 and 148 of the p53 gene but not at codon299, and more than 50% of the cancer cells showed accumulationof p53 protein immunohistochemically. The esophageal tumor,which was moderately differentiated squamous cell carcinoma,showed immunoreactivity for p53 within the nuclei of 25–50%of cancer cells with a missense mutation at codon 299 but notat codon 144 or 148. This cancer also showed immunoreactivityfor transforming growth factor alpha. On the other hand, thepoorly differentiated squamous cell carcinoma in the soft palateshowed negative immunoreactivity for p53 and no point mutationin exons 5 to 8 of the gene. These results suggest that thethree synchronous squamous cell carcinomas arose as independentevents.  相似文献   
52.
Summary Two cases of McArdle's syndrome are reported. One is a classical exaple; the other is unusual because of the in vitro presence of muscle phosphorylase activity. In the latter case. the electronmicroscopic investigation confirmed the diagnosis.The fine structural changes characteristic of this disease are summarized and it is concluded that histochemical studies alone are insufficient to exclude the diagnosis of McArdle's myopathy.  相似文献   
53.
We observed the attacks of nystagmus in a case of infantile spasms and carried out overnight sleep polygraphy. The following findings were obtained:
  • 1 Awake time was prolonged to 56% of TIB, while sleep time was markedly shortened to 44% of TIB. Also REM sleep time was reduced to 20% of SPT and deep slow sleep (stage N3) was absent.
  • 2 Attacks of nystagmus were observed only during wakefulness. At first, fast wave bursts appeared in the right occipital area, and were followed by left-upward deviations of eyeballs, and then the attacks of counterclockwise right-downward rotatory nystagmus. Also the fast wave bursts were succeeded by spreading of fast waves to adjacent areas. At the same time, EMG exhibited elevated muscle action potentials of mentalis and biceps fernoris. During the attacks of nystagmus, there was alteration of respiratory movements.
In NREM sleep, both fast wave bursts and the attacks of nystagmus were not observed. In REM sleep, the fast wave bursts and eye movements were observed but the attacks of nystagmus did not appear. During the fast wave bursts, alteration of respiratory movements were observed. From the results of this study, it was presumed that the brain lesions of this case were extended with severe degree of damage in the great parts of brain containing Cerebral cortex and brain stem.  相似文献   
54.
Summary Plasmalemmal vesicles and microvilli or filopodia in human astrocytoma were examined with thin-section and freeze-fracture techniques. The plasmalemmal vesicles, although sparsely scattered in distribution, were often aggregated in a curvilinear, semicircular, or circular fashion, and the involved plasma membrane was often protruded externally like a mound.Microvilli or filopodia were cross-fractured when fracture travelled within the plasma membrane resulting in a fracture face interrupted by numerous holes of cytoplasms. The microvilli were distributed in a concentrated manner on the free suface of the cell and often closely oriented in a linear, curvilinear, or circular fashion. They varied in size, form, and length. When they were arisen from a common hillock of the plasma membrane, its fracture face was elongated, up to 0.8 in length. Fenestrae were occasionally visible in attenuated cytoplasm which surrounded peripheral vacuole in the cell.  相似文献   
55.
Sano K  Morii K  Sato M  Mori H  Tanaka R 《Neurologia medico-chirurgica》2000,40(10):495-9; discussion 499-500
The mechanism of radiation-induced diffuse brain injury was investigated using a model of delayed myelination in the irradiated neonatal rat brain in which the number of oligodendrocytes decreases without associated necrosis of the cerebral white matter. Immunohistochemical analysis using antibody against the large myelin-associated glycoprotein, a specific marker of oligodendrocytes at an early stage of development, showed that the number of the oligodendrocytes associated with myelination decreased in the irradiated hemisphere 1 day after irradiation and remained low until 5 days after irradiation. In situ terminal deoxynucleotidyl transferase-mediated nick end-labeling assay revealed that apoptosis mainly occurred in the cerebral white matter of the irradiated hemisphere. Three hours after irradiation, apoptotic cells were found in the subcortical white matter and the periventricular white matter. Six hours after irradiation, apoptotic cells were found in the internal capsule, and the numbers of apoptotic cells in the periventricular white matter and subcortical white matter increased. One day after irradiation, the number of apoptotic cells in the periventricular white matter decreased. Three days after irradiation, apoptotic cells were not observed in the cerebral white matter. These results suggest that the oligodendrocytes associated with myelination may be damaged via radiation-induced apoptosis, and depletion of the oligodendrocytes may cause delay of myelination.  相似文献   
56.
PURPOSE: The aim of this report was to indicate both the advantages and disadvantages of local cell transfer therapy using ex vivo expanded autologous tumor-specific T lymphocytes (ATTLs) for recurrent cases of malignant gliomas. EXPERIMENTAL DESIGN: Subjects are 10 cases of malignant gliomas consisting of 7 cases of glioblastoma multiforme, 2 cases of anaplastic astrocytoma, and 1 case of anaplastic oligoastrocytoma. All cases were recurrences. ATTLs were induced by coculturing peripheral blood mononuclear cells with autologous tumor cells in medium containing interleukin-1, -2, -4, and -6 and administered into the local tumor site in total numbers of 3-247 x 10(7) cells. As end points, tumor response and survival time were analyzed observing clinical state. RESULTS: Five cases responded to this therapy (namely, one case showed complete remission, and four cases had a partial response). There were three cases of no change, and two cases of progressive disease. The overall tumor response rate was 50%. No complications were noticed, except for two cases of minor local hemorrhage and eight cases of temporary fever. Nine cases died of further tumor progression, and one case died of aspiration pneumonia, and the cause-specific survival analysis indicates that the median survival time was 5 months from the initial ATTL injection. CONCLUSIONS: The results suggest that local administration of ATTLs is effective in recurrent malignant gliomas in that it demonstrated a high benefit:risk ratio with minor side effects. Although its antitumor effect may be temporary in some advanced cases, it is highly possible that the tumor could be stabilized when conditions are optimal.  相似文献   
57.
A 65-yr-old man who underwent pancreaticoduodenectomy with portal vein resection for pancreatic cancer is alive 8 yr after surgery. Originally, computed tomography (CT) revealed an 8-cm tumor in the pancreatic head. The tumor had infiltrated the portal vein, but grew expansively, so there was neither biliary obstruction nor jaundice. Pancreaticoduodenectomy with resection of the portal vein was performed for pancreatic cancer. Many tumor-infiltrating lymphocytes were seen within cancer cell nests on routine histopathology. We performed immunostaining for CD8, and found that a large number of the lymphocytes were CD8+ T cells. The patient’s prognosis was considered poor because the tumor was large and had infiltrated the portal vein. We suspect that long-term survival may be related to the response of CD8+ T cells to the cancer.  相似文献   
58.
Patterns of radiologic response of 10 thymomas treated by preoperative radiotherapy (RT) (18-20 Gy/2 weeks) were determined in conjunction with histologic response. Changes in tumor volume were evaluated with CT scans obtained 5 to 36 days before and 14 to 24 days after the initiation of RT and before surgery. The extent of tumor volume reduction (TR) varied widely (40-78%), while the mean daily volume decrement expressed as a percentage of the pre-RT tumor volume correlated significantly with the pre-RT tumor volume. Histologically, the tumors, all of which were resected 17 to 33 days after RT initiation, generally consisted of predominant fibrous tissues, rare necrotic foci, and few epithelial cells. The TR did not correlate with pre-RT tumor volume, observation period, histologic subtype, or quantity of remaining epithelial cells. The TR of thymomas does not predict RT impact on tumor cells but does reflect the quantity of inherent tumor stroma.  相似文献   
59.
Fexofenadine is a selective, nonsedating H(1)-receptor antagonist approved for symptoms of allergic conditions, which is mainly excreted into feces via biliary excretion. The purpose of this study is to investigate its pharmacokinetics in mice and rats to determine the role of P-glycoprotein (P-gp) in its biliary excretion. In mice, biliary excretion clearance (17 ml/min/kg) accounted for almost 60% of the total body clearance (30 ml/min/kg). Comparing the pharmacokinetics after intravenous and oral administration indicated that the bioavailability of fexofenadine was at most 2% in mice. Knockout of Mdr1a/1b P-gp did not affect the biliary excretion clearance with regard to both plasma and liver concentrations, whereas the absence of P-gp caused a 6-fold increase in the plasma concentration after oral administration. In addition, the steady-state brain-to-plasma concentration ratio of fexofenadine was approximately 3-fold higher in Mdr1a/1b P-gp knockout mice than in wild-type mice. Together, these results show that P-glycoprotein plays an important role in efflux transport in the brain and small intestine but only a limited role in biliary excretion in mice. In addition, there was no difference in the biliary excretion between normal and hereditarily multidrug resistance-associated protein 2 (Mrp2)-deficient mutant rats (Eisai hyperbilirubinemic rats) and between wild-type and breast cancer resistance protein (Bcrp) knockout mice. These results suggest that the biliary excretion of fexofenadine is mediated by unknown transporters distinct from P-gp, Mrp2, and Bcrp.  相似文献   
60.
The aim of antitumor immunotherapy is to induce CTL responses against autologous tumors. Previous work has shown that fusion of human dendritic cells and autologous tumor cells induce CTL responses against autologous tumor cells in vitro. However, in the clinical setting of patients with colorectal carcinoma, a major difficulty is the preparation of sufficient amounts of autologous tumor cells. In the present study, autologous dendritic cells from patients with colorectal carcinoma were fused to allogeneic colorectal tumor cell line, COLM-6 (HLA-A2(-)/HLA-24(-)), carcinoembryonic antigen (CEA)(+), and MUC1(+) as an alternative strategy to deliver shared colorectal carcinoma antigens to dendritic cells. Stimulation of autologous T cells by the fusion cells generated with autologous dendritic cells (HLA-A2(+) and/or HLA-A24(+)) and allogeneic COLM-6 resulted in MHC class I- and MHC class II-restricted proliferation of CD4(+) and CD8(+) T cells, high levels of IFN-gamma production in both CD4(+) and CD8(+) T cells, and the simultaneous induction of CEA- and MUC1-specific CTL responses restricted by HLA-A2 and/or HLA-A24. Finally, CTL induced by dendritic cell/allogeneic COLM-6 fusion cells were able to kill autologous colorectal carcinoma by HLA-A2- and/or HLA-A24-restricted mechanisms. The demonstration of CTL activity against shared tumor-associated antigens using an allogeneic tumor cell line, COLM-6, provides that the presence of alloantigens does not prevent the development of CTL with activity against autologous colorectal carcinoma cells. The fusion of allogeneic colorectal carcinoma cell line and autologous dendritic cells could have potential applicability to the field of antitumor immunotherapy through the cross-priming against shared tumor antigens and provides a platform for adoptive immunotherapy.  相似文献   
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