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31.
Franz -X. Beck Masayoshi Sone Adolf Dörge Klaus Thurau 《Pflügers Archiv : European journal of physiology》1992,422(3):233-238
Sodium absorption in distal tubule segments was stimulated by increasing the distal delivery via infusion of hypertonic saline. In these animals, and in control rats, electrolyte concentrations in thick ascending limb cells, light and dark cells of the collecting duct in the outer and inner stripe of the outer medulla and in cells of the proximal straight tubule (outer stripe only) were studied. The measurements were performed by electron microprobe analysis of freeze-dried cryosections of the outer medulla. In addition, organic osmolytes (glycerophosphorylcholine, betaine and myo-inositol) were measured by high performance liquid chromatography in cortex and outer medulla. Augmented delivery of sodium chloride to the distal tubule was associated with increased sodium concentrations of thick ascending limb cells both in the outer and inner stripe and of medullary collecting duct light and dark cells in the outer stripe. While the sum of organic osmolyte concentrations was 28% higher in the outer medulla of the salt-loaded animals compared with controls, this value was unchanged in the renal cortex. These findings indicate that the primary event underlying stimulation of sodium absorption along the thick ascending limb during increased distal sodium delivery is enhanced entry of sodium across the apical cell membrane. This would be expected to lead to higher cell sodium concentrations and stimulation of basolateral active Na-K-exchange. The enhanced transport activity of outer medullary tubules may be associated with increased interstitial tonicities and intracellular retention of organic osmolytes. 相似文献
32.
A surface graft polymer with one or two phosphorylcholine (PC) polarheads at the terminus of the growing chain end was prepared by sequential reactions on a glass substrate. The dithiocarbamate group covalently bound to glass surfaces was derivatized with one or two PC groups and then irradiated with ultraviolet light in the presence of N,N-dimethylacrylamide (DMAAm). X-ray photoelectron spectroscopy, wettability measurements and dye staining experiment for the PC group showed that the resultant graft copolymers were produced via iniferter-based quasi-living radical polymerization, in which the polyDMAAm graft chain contains one or two PC groups at the terminal end of the graft chain. These polymer surface grafts may help provide biocompatibility. 相似文献
33.
Masayoshi Kaiho Toshikazu Nakamura Masayoshi Kumegawa 《Anatomical record (Hoboken, N.J. : 2007)》1975,183(3):405-419
The synthesis of zymogen-like secretory granules in convoluted tubules of mouse submandibular gland (SMG) was investigated by histometry, light microscopy and electron microscopy. In normal males secretory granules in the SMG increased greatly from 25 days after birth and reached a maximum level 50 days after birth. Castration of adult male mice markedly decreased the level, but it was completely restored by testosterone administration. A parallel was found between change in the granule level and the amount of rough endoplasmic reticulum (RER) in the convoluted tubular cells during development or after various treatments. Development of the Golgi apparatus was also observed in the cells when the granules increased. Both the increase in the granules and in the RER induced by testosterone were prevented by actinomycin D or puromycin. These results indicate that the granule contents are synthesized on the RER under the control of testosterone, and then condensed in the Golgi apparatus. 相似文献
34.
Katsuhiko Aoyama Kazuo Terashima Yutaka Imai Noriko Katsushima Yoshio Okuyama Katsuhisa Niikawa Takeo Mukada Katsuro Takahashi 《Pathology international》1984,34(2):375-388
The present paper deals with immunohistochemical and ultrastructural study of the lymph nodes of sinus histiocytosis with massive lymphadenopathy (Rosai and Dorfman, SHML) of a 12-year-old Japanese boy. This is the fourth case in Japan. Osseous manifestation was also found in the bilateral ulnae. With hallmarks of S-100 protein and interdigitating cytoplasmic extensions, the phagocytizing histiocytes proliferating in the sinuses were considered to be derived mostly from interdigitating cells in the paracortex or T cell dependent area, which have heretofore been regarded as nonphagocytizing. Furthermore, it is most interesting that lymphoid cells bearing thymic cortical cell-antigen (OKT 6) were increasingly recognized in the patient's peripheral blood. These results suggested that SHML is a specialized reactive histiocytosis analogous to histiocytosis X and histiocytic medullary reticulosis. 相似文献
35.
Treatment of persistent sleep-wake schedule disorders in adolescents with methylcobalamin (vitamin B12). 总被引:1,自引:2,他引:1
Two adolescent patients suffering from persistent sleep-wake schedule disorders appear to have responded to treatment with vitamin B12 (methylcobalamin). A 15-year-old girl with delayed sleep phase syndrome (DSPS) and a 17-year-old boy with hypernychthemeral syndrome complained of not being able to attend school despite many trials of medication. The improvement of the sleep-wake rhythm disorders appeared immediately after the administration of high doses (3,000 micrograms/day) of methylcobalamin. Neither patient showed any laboratory or clinical evidence of vitamin B12 deficiency or hypothyroidism (which can cause B12 deficiency). Serum concentrations of vitamin B12 during treatment were in the high range of normal or above normal. The duration of the sleep period of the DSPS patient decreased gradually from 10 hours to 7 hours, and the time of sleep onset advanced from 2 a.m. to midnight. The period of the sleep-wake cycle of the hypernychthemeral patient was 24.6 hours before treatment and 24.0 hours after treatment. The relationship between the circadian basis of these disorders and vitamin B12 and its metabolites is discussed. 相似文献
36.
K Terashima K Takahashi M Kojima Y Imai S Tsuchida S Migita S Ebina C Itoh 《Acta pathologica japonica》1978,28(1):111-138
An autopsy case of systemic histiocytosis with excessive deposition of kappa-type light chain crystals was reported in a 58 year-old man who had consistently showed kappa-type light chain paraproteinemia, Bence Jones proteinuria and hypogammaglobulinemia for about 10 years until his death. However, no bony destruction was found by repeated X-ray examinations. At autopsy, extensive hyperplasia of crystal-storing histiocytes was observed in the bone marrow, spleen, liver, lymph nodes, interstitial tissues of visceral organs and loose connective tissues. In the bone marrow and some other tissues, mild proliferation of plasmocytoid cells containing small crystals were found. Histochemically the crystals positively stained with various methods for amino acids and proteins, especially with Weigerts' method for fibrin. Ultrastructurally intralysosomal crystal deposition was confirmed in the storage histiocytes and derivation of the crystals from Golgi's sacculi in the plasmocytoid cells was suggested. Biochemically the crystals were regarded as mainly consisting of dimers of a variable half of light chain immunoglobulin and immunochemically and immunohistochemically reacted to anti-kappa type light chain serum. Such a generalized storage histiocytosis may be secondarily induced by immunoglobulin synthesized in plasmocytoid cells. 相似文献
37.
Konno A Hoshino Y Terashima S Motoki R Kawaguchi T 《Clinical & experimental metastasis》2002,19(1):61-70
Carbohydrate expression of cancer cells is closely related to the metastatic nature of colorectal cancer. In the present study we investigated the relevance of carbohydrate expression profiles of colorectal cancer cells in the primary lesion to metastatic distribution patterns as well as prognosis in 134 cases. Carbohydrate expression was estimated by histochemistry with 17 kinds of lectins and 3 kinds of Lewis-related monoclonal antibodies (MAbs), and correlations between the staining and clinicopathological parameters were examined. The results showed that lymphatic invasion, lymph node metastasis, and peritoneal metastasis correlated with staining with lectins that bind galactose/N-acetylgalactosamine residues (Gal/GalNAc) such as Maclura pomifera (MPA), Arachis hypogaea (PNA), Helix pomatia (HPA), and Vicia villosa (VVA). In contrast, hepatic metastasis correlated with staining with Anguilla anguilla lectin (AAA), anti-LewisX (LEX-2), anti-sialyl Lewisa (NS19-9), and anti-sialyl-dimeric LewisX (FH-6) MAbs, all of which bind preferentially to fucosylated carbohydrate chains. The five-year survival rate of patients was related to the staining of cancers with MPA, HPA, FH-6 or NS19-9, and MPA- and FH-6 staining were independent prognostic factors. We conclude that carbohydrate expression profiles of cancer cells are relevant to the route of tumor cell dissemination, metastatic pattern as well as prognosis of colorectal cancer. 相似文献
38.
Differential expression of PD-L1 and PD-L2, ligands for an inhibitory receptor PD-1, in the cells of lymphohematopoietic tissues 总被引:27,自引:0,他引:27
PD-1 is a member of the immunoglobulin superfamily expressed on immune cells, including T and B cells, and is involved in the delivery of inhibitory signal upon engagement of its ligands, PD-L1 and PD-L2. While the expression profile of PD-1 has been well documented, the analysis of PD-L1 and PD-L2 distributions on a protein basis has not been carried out because of the lack of available monoclonal antibodies specific for the molecules. In this study, we established two monoclonal antibodies, 1-111A and 122, specific for murine PD-L1 and PD-L2, respectively, and examined their expression profiles. Based on flow cytometric analyses, the expression of PD-L1 was detected in a variety of lymphohematopoietic cell types, including a minor proportion of T and B cells in the spleen, majority of pre-B cells and myeloid cells in bone marrow and subsets of thymocytes, while the expression of PD-L2 was not observed in the lymphohematopoietic cells at all. Notably, a significant proportion of the most immature lineage-marker-negative and c-Kit-positive bone marrow cells containing stem cells did express PD-L1. Following mitogenic stimulation, essentially all lymphocytes expressed PD-L1. Furthermore, a variety of leukemic lines also expressed PD-L1, while none of them did PD-L2. Thus, present results demonstrate the distinct expression patterns of PD-L1 and PD-L2 with the cells of lymphohematopoietic tissues exclusively expressing the former. 相似文献
39.
A histological evaluation for guided bone regeneration induced by a collagenous membrane 总被引:5,自引:0,他引:5
Taguchi Y Amizuka N Nakadate M Ohnishi H Fujii N Oda K Nomura S Maeda T 《Biomaterials》2005,26(31):6158-6166
This study was designed to evaluate the histological changes during ossification and cellular events including osteogenic differentiation responding to collagenous bioresorbable membranes utilized for GBR. Standardized artificial bony defects were prepared at rat maxillae, and covered with a collagenous bioresorbable membrane. These animals were sacrificed at 1, 2, 3 and 4 weeks after the GBR-operation. The paraffin sections were subject to tartrate resistant acid phosphatase (TRAP) enzyme histochemistry and immunohistochemistry for alkaline phosphatase (ALP), osteopontin (OP) and osteocalcin (OC). In the first week of the experimental group, woven bone with ALP-positive osteoblasts occupied the lower half of the cavity. The collagenous membrane included numerous ALP-negative cells and OP-immunoreactive extracellular matrices. At 2 weeks, the ALP-, OP- and OC-immunoreactivity came to be recognizable in the region of collagenous membrane. Since ALP-negative soft tissue separated the collagenous membrane and the new bone originating from the cavity bottom, the collagenous membrane appeared to induce osteogenesis in situ. At 3 weeks, numerous collagen fibers of the membrane were embedded in the adjacent bone matrix. At 4 weeks, the membrane-associated and the cavity-derived bones had completely integrated, showing the same height of the periosteal ridge as the surrounding alveolar bones. The collagen fibers of a GBR-membrane appear to participate in osteogenic differentiation. 相似文献
40.
A MicroRNA signature associated with prognosis and progression in chronic lymphocytic leukemia 总被引:2,自引:0,他引:2