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31.
32.
Mice homozygous for klotho gene deletion are well established aging models as they mimic certain aspects of human senescence e.g. osteoporosis. Induced senescence may affect cellular functions and alter the histological properties of the extracellular matrices. The present study examined the histological and ultrastructural features of osteocytes and the surrounding bone matrix in klotho-deficient mice. As expected, osteoblasts showed a flattened shape with a weak immunoreactivity for alkaline phosphatase, and the bone matrix contained many empty osteocytic lacunae. The walls of both normal and empty lacunae were intensely immunopositive for osteopontin and dentin matrix protein-1, but featured an inconsistent immunoreactivity for osteocalcin and type I collagen. Not surprisingly, TUNEL-positivity, indicative of apoptosis, was found in many osteoblasts, osteocytes, and bone marrow cells of the klotho-deficient mice. In transmission electron microscopy, an amorphous matrix containing non-collagenous organic materials was recognizable around osteoblasts and in the osteocytic lacunae. Some osteoblasts on the bone surface featured these amorphous materials in vacuoles associated with their trans-Golgi network, indicating that, under klotho-deficient conditions, they synthesize and secrete the non-collagenous structures. Some osteocytes displayed pyknosis or degenerative traits. Thus, our findings provide histological evidence that klotho gene deletion influences the spatial distribution of osteocytes and the synthesis of bone matrix proteins in addition to the accelerated aging of bone cells.  相似文献   
33.
Acetaldehyde syndrome after celiac plexus alcohol block   总被引:1,自引:0,他引:1  
In the course of celiac plexus alcohol block, facial flushing, palpitations, and hypotension are occasionally incurred in some patients. We hypothesized that the phenomenon represents acetaldehyde syndrome, not response to increased blood levels of ethanol as might be supposed. In order to prove our hypothesis, we selected five patients scheduled to undergo celiac plexus alcohol block, and, with their consent, we measured blood concentration of ethanol and acetaldehyde before and for 6 hr after the block. We also determined the phenotypes of aldehyde dehydrogenase (ALDH) in their hair roots. We found that "flushers" are found exclusively among subjects without ALDH I, and that their blood levels of acetaldehyde were significantly higher than those of "non-flushers" within 10 min after the block. The flushers also gave histories of facial flushing after ingestion of small amounts of ethanol. On the basis of such histories one can anticipate whether acetaldehyde syndrome is likely or unlikely to accompany the block.  相似文献   
34.
Although single-lung transplant on the side with better lung function is challenging in patients with significantly asymmetrical lung function between the right and left sides, it sometimes can be a realistic option because of the recipient's condition and from the viewpoint of organ sharing. We report our experience with a successful case of single-lung transplant on the side with a pulmonary perfusion ratio of 89%. The transplant was performed with the patient under central venoarterial extracorporeal membrane oxygenation through a clamshell incision, and the patient had an acceptable short- and long-term outcome with a remarkable improvement of lung function.  相似文献   
35.
The purpose of this study was to describe the results of definitive radiotherapy (RT) with concurrent chemotherapy for maxillary sinus carcinomas (MSCs) with neck lymph node metastasis to clarify its limitation. Local control (LC), progression-free survival (PFS) and overall survival (OS) rates were calculated using the Kaplan–Meier method and were compared between subgroups using the log rank test. Toxicity was classified using common terminology criteria of adverse events version 5.0. Eighteen patients with inoperable MSC with neck lymph node metastasis including 12 men and 6 women with a median age of 67 years were analyzed. The histologic diagnoses were as follows: 16 patients had squamous cell carcinomas and 2 had other histology. Four patients had stage T3 MSC, 6 had T4a and 8 had T4b. Among 18 patients, 7 received concurrent systemic chemotherapy and 11 received selective arterial chemo-infusion. The median follow-up period was 17 months. The 2-year LC, PFS and OS rates for the entire cohort were 34, 31 and 46%, respectively. No significant differences were observed for LC, PFS and OS rates between systemic chemotherapy and selective arterial chemo-infusion cohorts. Grade 3 or higher acute toxicity, including both non-hematological and hematological, was observed in nine patients (50%), while no grade 3 or higher late toxicity was observed. In conclusion, we described the results of definitive RT for MSCs with neck lymph node metastasis. Local recurrence of primary tumor was a frequent pattern of failure and it should be addressed in future study.  相似文献   
36.
Unitary analysis of retino-geniculate response time in rats   总被引:1,自引:0,他引:1  
H Noda  K Iwama 《Vision research》1967,7(3):205-213
  相似文献   
37.
Vascular Ehlers–Danlos syndrome (vEDS) is a hereditary connective tissue disorder (HCTD) characterized by arterial dissection/aneurysm/rupture, sigmoid colon rupture, or uterine rupture. Diagnosis is confirmed by detecting heterozygous variants in COL3A1. This is the largest Asian case series and the first to apply an amplification-based next-generation sequencing through custom panels of causative genes for HCTDs, including a specific method of evaluating copy number variations. Among 429 patients with suspected HCTDs analyzed, 101 were suspected to have vEDS, and 33 of them (32.4%) were found to have COL3A1 variants. Two patients with a clinical diagnosis of Loeys–Dietz syndrome and/or familial thoracic aortic aneurysm and dissection were also found to have COL3A1 variants. Twenty cases (57.1%) had missense variants leading to glycine (Gly) substitutions in the triple helical domain, one (2.9%) had a missense variant leading to non-Gly substitution in this domain, eight (22.9%) had splice site alterations, three (8.6%) had nonsense variants, two (5.7%) had in-frame deletions, and one (2.9%) had a multi-exon deletion, including two deceased patients analyzed with formalin-fixed and paraffin-embedded samples. This is a clinically useful system to detect a wide spectrum of variants from various types of samples.  相似文献   
38.
We investigated the synergetic effects of 1-(5-isoquinolinesulfonyl)-2-methylpiperazine dihydrochloride (H-7) on cis-diamminedichloroplatinum(II) (CDDP) cytotoxicity to KB cells, a human pharyngeal carcinoma cell line, and explored the possible mechanism whereby it exerted these effects. In vitro treatment with H-7 markedly decreased protein kinase C (PKC) activity in KB cells and significantly sensitized the cells to CDDP. Treatment of KB cells with H-7 induced a dose-dependent depletion of intracellular glutathione (GSH) levels. These results suggest that the decreased GSH content induced by H-7 may be involved in sensitizing KB cells to CDDP.  相似文献   
39.
To assess the feasibility and efficacy of rhGM-CSF in ameliorating chemotherapy-induced leukopenia in patients with advanced non-small-cell lung cancer, we conducted a double-blind placebo controlled phase III study in a multicenter setting. Patients were eligible if they had cytologically or histologically proven cancer, no prior chemotherapy, stage IIIB or IV disease, an Eastern Cooperativve Oncology Group (ECOG) performance status of 0–2, an age of less than 76 years, and no symptomatic brain metastasis, disseminated bone metastasis, or previous vertebral/pelvic irradiation. The chemotherapy regimen consisted of mitomycin given at 8 mg/m2 on day 1, cisplatin given at 100 mg/m2 on day 1, and vindesine given at 3 mg/m2 i.v. on days 1 and 8 (MVP). If the granulocyte nadir count recorded after the first cycle of MVP was less than 1,000/mm3, patients were randomly assigned to receive recombinant human granulocyte-macrophage colonystimulating factor (rhGM-CSF) or placebo during the second cycle of MVP. The dose of rhGM-CSF was 125 g/m2 given daily s.c. for 14 consecutive days starting on day 2. Of the 52 patients enrolled, 45 were evaluable. The nadir of granulocytes was significantly lower in the placebo group (P=0.007). The period during which the granulocyte count was less than 1,000/mm3 was significantly longer in the placebo group (median, 6 vs 10 days;P=0.04). The incidence of adverse effects related to rhGM-CSF, such as fever (38°C) and skin rash, was significantly higher in the rhGM-CSF group (P=0.011). The rate of response to chemotherapy did not significantly differ between the two groups. In conclusion, rhGM-CSF reduced the duration of chemotherapy-induced granulocytopenia. The clinical usefulness of this agent may be deminished because of the adverse effects encountered when it is used in combination with a moderately myelotoxic chemotherapy regimen.Institutions of the BI 71.018 Cooperative Study Group, National Cancer Center Research Institute (N. Saijo, Chairman): Douai Memorial Hospital (Y. Sano), Kanagawa Prefectural Cancer Center (K. Noda), Kantou Teishin Hospital (T. Uzawa), National Medical Center (J. Kabe), Shizuoka Prefectural General Hospital (H. Etou), Teikyo University (K. Mano), Tochigi Prefectural Cancer Center (Y. Saito), Tokyo Geriatric Medical Center (A. Kida), Tokyo Teishin Hospital (T. Morinari), Tokyo Metropolitan Komagome Hospital (S. Kudo), Tokyo Metropolitan Hiroo Hospital (A. Fujikawa), Toranomon Hospital (K. Nakada), Yokohama Municipal Hospital (K. Watanabe), National Cancer Center Central Hospital (K. Eguchi)  相似文献   
40.
We examined the effect of saturated fatty acids with carbon number from 2 to 10 on proliferation and survival of rat untransformed fibroblast 3Y1 cells and its transformed derivation induced by Simian virus 40 (SV-3Y1). Acetic acid (C2) had no effect on proliferation of these cells. Among medium-chain fatty acids (C6-C10), caproic acid (C6) showed the lowest proliferation inhibitory effect. Caprylic (C8), pelargonic (C9), and capric acid (C10) exerted killing activity to both 3Y1 cells and SV-3Y1 cells, and the toxicity increased with the elongation of their alkyl chains. The toxicity was a little greater to 3Y1 cells than to SV-3Y1 cells. In contrast, short-chain fatty acids caused reversible proliferation arrest in 3Y1 cells at 25 mM in propionic (C3), 5 mM in butyric (C4) and 10 mM in valeric (C5) acids. These short-chain fatty acids arrested 3Y1 cells not only in the GI phase but also in the G2 phase of the cell cycle. To SV-3Y1 cells, however, these short-chain fatty acids were cytotoxic. The cytotoxicity to SV-3Y1 cells was the greatest in butyric acid among short-chain fatty acid tested. These results suggest that short-chain fatty acids exert ploliferation-arresting activity against normal cells while exerting killing activity to the transformed cells.  相似文献   
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