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51.
Possible role of hepatocyte growth factor in regeneration of human peritoneal mesothelial cells 总被引:5,自引:0,他引:5
Naiki Y Matsuo K Matsuoka T Maeda Y 《The International journal of artificial organs》2005,28(2):141-149
Human peritoneal mesothelial cells (HPMCs) play an important role in peritoneal functions. During long term peritoneal dialysis, it has been reported that HPMCs are damaged by high glucose solution via the signal of transforming growth factor (TGF)-beta1 produced by HPMCs. In this study, we focused on the effect of hepatocyte growth factor (HGF), known as an anti-fibrotic and anti-TGF-beta1 agent, on HPMCs damaged by high glucose solution. HPMCs were isolated from specimens of the omentum from nonuremic patients after informed consent had been obtained. After confirming adhesion for 6 hours, 100 microL of DMEM with 0.5%FCS were added at different concentrations (D-glucose; 6, 30 mM) with or without HGF (10, 30, 100 ng/mL) for 48 hours. We examined the effects of a high concentration of glucose and then focused on following four critical points: 1) the production of HGF from HPMCs exposed to a high concentration of glucose, 2) the expression of c-Met on HPMCs, 3) the viability of those cells, and 4) matrix metalloproteinase-2 (MMP-2) and tissue inhibitors of metalloproteinase-2 (TIMP-2). The following significant changes are described herein: high glucose solution and TGF-beta1 i) decreased HGF production from HPMCs and ii) up-regulated expression of c-Met on HPMCs, and addition of HGF iii) restored viability of HPMCs damaged by glucose, iv) suppressed TGF-beta1 production by HGF, and v) induced up-regulation of MMP-2 and decreased TIMP-2 production by HPMCs. Levels of HGF decreased by high concentrations of glucose in the peritoneal cavity may induce the loss of HPMCs and thereby result in peritoneal fibrosis. These results suggest that HGF is an effective agent in the regeneration of peritoneal membrane damaged by high glucose solution. 相似文献
52.
Seo B Ikeda K Emoto N Choi DJ Hwang JY Matsuo M Kim EJ Cheon IS 《Yonsei medical journal》2000,41(1):49-55
The favorable effects of estrogen on cardiovascular diseases can be explained by several mechanisms such as changes in serum lipid profiles and thrombogenecity. Estrogen also affects the vascular tone, but there has been no report in which the effect of estrogen was tested comprehensively for several vasoactive substances, especially after long-term administration. Two weeks after bilateral ovariectomy in 8-week old female Sprague-Dawley rats, placebo or 17 beta-estradiol (E2) pellets (0.5 mg; released over 3 weeks) were implanted subcutaneously. Two weeks after pellet implantation, organ chamber experiments were performed using aortae. Compared with control, E2-treated vessels showed impaired endothelium-dependent relaxation to acetylcholine. E2 enhanced the contraction to norepinephrine and U46619 and had no effect on endothelin-1-induced contraction. In contrast, the contraction to angiotensin (AT)-II was inhibited by E2. Northern blot analysis for AT1 receptor expression using cultured aortic smooth muscle cells showed no difference between control and E2-treated cells, suggesting that AT1 receptor downregulation is not the likely mechanism. These results suggest that E2 affects the vascular tone variably according to vasoactive substances. 相似文献
53.
One and two-month-old chickens were killed at mid light and mid dark under the experimental photoperiod (LD 12: 12). The pineal glands of the young chickens are composed of parenchymal cells and large follicles, presenting a tubulofollicular arrangement. The sensory-like pinealocytes are pear-shaped and have a cilium with 9 + 0 axial configuration projecting into the lumen. Their cytoplasm has cell organelles, small granulated vesicles about 100 nm in diameter and synaptic ribbons. The concentric lamellar complexes like myelin sheaths are frequently observed in the follicular lumen. The secretory-like supporting cells have irregular-shaped microvilli and some granulated vesicles about 200 nm in diameter in the vicinity of the apical surfaces. Occasionally, a few nerve cells are found in the pineal parenchyma. It was found that the sensory-like pinealocytes of the young chickens have many mitochondria, well-developed Golgi complexes and large lysosomes in solid type in the light period, whereas they have a few cell organelles and somewhat smaller rod-like lysosomes with some vacuoles in the dark period. On the other hand, the sensory-like pinealocytes have more synaptic ribbons in the dark period than in the light period. 相似文献
54.
This report describes the morphological responses of unstimulated and stimulated non-functioning adrenocortical adenoma in culture. The removed adrenocortical adenoma was composed mainly of clear-type cells and partially had a small area of cholesterol granuloma. These adenoma cells had many lipid droplets and round to long rod-shaped mitochondria with tubular or tubulo-lamellar cristae which were similar to those in Cushing's adenoma. The non-functioning adrenocortical adenoma cells which were incubated in vitro under ACTH (10 mIU/ml) and angiotensin II (10(-6) M/ml) stimulation, were examined by phase contrast microscopy, transmission and scanning electron microscopy, and the content of cortisol and aldosterone in the culture medium was measured by radioimmunoassay. As a result of exposure of ACTH, the cultured cells revealed the retraction response and production of cortisol and aldosterone. After administration of ACTH for many days, the cultured cells showed characteristic changes in sER and mitochondria. The sER were markedly developed and packed tightly into a network of dilated tubules. Mitochondria were larger and more numerous than in the unstimulated cells. The mitochondria appeared to be entwined by the tubules of the sER. Lipid droplets decreased in number. 相似文献
55.
Matsuo T Wanaka K Asada R 《Rinsho byori. The Japanese journal of clinical pathology》2005,53(7):622-629
Heparin-induced thrombocytopenia(HIT) due to immunological mechanisms is known as an important adverse reaction to heparin treatment, and heparin treatment should be applied while keeping in mind the risk of onset of HIT 5-14 days after the initiation of heparin. The presence of HIT had not been fully recognized in clinical practice in Japan despite the management of HIT being well confirmed in Western countries. Recognition of HIT has increased since argatroban, a direct thrombin inhibitor, obtained the approval of the FDA for prevention and treatment of HIT. Although the incidence of HIT in Japan has not yet been clarified, there is some evidence that HIT is encountered in critically ill patients undergoing heparin anticoagulation. Clinical diagnosis of HIT is performed by means of thrombocytopenia of a drop of 50% or 100 x 10(30/microl for 5 -14 days after starting heparin treatment. Confirmatory laboratory tests examine whether the patients have antibodies against heparin/PF4 complexes or not. Two assay tests for detecting heparin/PF4 complex antibodies are available in Japan. As a functional test, the heparin-induced platelet aggregation method is easily performed and the result is obtained in a short time. The result of the test has, however, been misleading due to the selection of donors. Low platelet activity of the donors on the addition of heparin induces a negative response in spite of positive antibodies in the sample. Before testing samples, it is important to check heparin reactivity of the donor's platelets. Enzyme immunoassay detecting the antibodies is available as a commercial kit. Sensitivity obtained by enzyme immunoassay is very high and often introduces false-positives. Careful attention to interpretation of the result is required. Treatment of HIT should be started at the time of recognition of thrombocytopenia while antibody testing for HIT is performed. As an alternative anticoagulant to heparin, argatroban should immediately be applied to avoid complication of thrombosis. Thrombocytopenia and hypercoagulability quickly recover to the preheparin level by the appropriate use of argatroban. 相似文献
56.
Lai PS Takeshima Y Adachi K Van Tran K Nguyen HT Low PS Matsuo M 《Journal of human genetics》2002,47(10):0552-0555
The frequency and distribution of deletions of 19 deletion-prone exons clustered in two hot spots in the proximal and central
regions of the dystrophin gene were compared in three populations from Singaporean, Japan, and Vietnam. DNA samples obtained
from 105 Singaporean, 86 Japanese, and 34 Vietnamese Duchenne muscular dystrophy patients were examined by polymerase chain
reaction amplification. Deletions of the examined exons were found in 51.2% of Japanese patients but in 40.0% or less of the
Singaporeans and Vietnamese. About two thirds of the deletions were localized in the central region and the remaining deletions
were clustered at the proximal region. The most commonly deleted exons at the central deletion hot spot were exon 50 in the
Singaporean, exons 49 and 50 in the Japanese, and exon 51 in the Vietnamese population. At the proximal deletion hot spot,
the most commonly deleted exons were exons 6 and 8 in the Singaporeans, exons 12 and 17 in the Japanese, and exons 8 and 12
in the Vietnamese. Two cases each from Singapore and Japan had large-scale gross mutations spanning both deletion hot spots.
Our results suggest that, although the presence and frequency of the two deletion hot spots may be similar in the three Asian
populations analyzed, the distribution and frequency of deletions among the different exons can vary as a result of population-specific
intronic sequences that predispose individuals to preferential deletion breakpoints.
Received: May 20, 2002 / Accepted: July 1, 2002 相似文献
57.
Tachimoto H Kikuchi M Hudson SA Bickel CA Hamilton RG Bochner BS 《American journal of respiratory cell and molecular biology》2002,26(6):645-649
Adhesion molecules and chemokines contribute to selective eosinophil recruitment in allergic inflammation. In this study, we examined the effects of eotaxin-2, a CCR3-specific chemokine, on integrin-mediated eosinophil adhesion to vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), or both using a parallel plate flow system. Tissue culture plates were coated with various combinations of VCAM-1, ICAM-1, and/or eotaxin-2. Human eosinophils were infused at physiologic shear stress (0.5 dyn/cm(2)) for 10 min, and the numbers of attached eosinophils were monitored using video microscopy. Cells accumulated efficiently on VCAM-1 and even better on surfaces co-coated with VCAM-1 and ICAM-1, but poorly on surfaces coated with ICAM-1 or bovine serum albumin alone. When eotaxin-2 was co-immobilized with adhesion proteins, fewer cells adhered to VCAM-1 and more adhered to ICAM-1, whereas levels of attachment to VCAM-1 plus ICAM-1 showed no net change. However, experiments with adhesion molecule blocking monoclonal antibody showed that the contribution of ICAM-1-mediated adhesion was always greater if eotaxin-2 was present. Pretreatment of cells with a CCR3-blocking mAb, or PD98059, a MAP-kinase inhibitor, prevented the eotaxin-2-induced changes in eosinophil attachment. These data suggest that eotaxin-2, acting via MAP kinases, may facilitate eosinophil recruitment at sites of allergic inflammation by shifting their adhesion molecule usage away from VCAM-1-dominated to ICAM-1-dominated pathways. 相似文献
58.
1. The responses of 90 cortical neurons in the somatosensory and gustatory areas were recorded with chronically implanted fine wires in freely moving Wistar rats. The responses were analyzed mainly while the animals were freely licking solutions and eating dry pellets. Cortical neurons were classified into several groups according to their response properties. 2. "Mechanosensitive" neurons (n = 20) showed rhythmic phasic activity in different phases of the licking cycle, depending on the location of their receptive field in the peripheral orofacial region. 3. "Movement-related" neurons (n = 27) changed their activities tonically during licking, chewing, or grooming behavior. The responses were either excitatory or inhibitory. Receptive fields and adequate stimuli could not be identified. These neurons might receive somatosensory (except light tactile) inputs from wide or deep areas of intra- or perioral regions, or might be related to orofacial active movement. 4. "Taste" neurons (n = 35) increased or decreased their discharge rates during licking of particular taste solutions. Some taste neurons received convergence from somatosensory inputs. 5. "Temperature" neurons (n = 2) responded exclusively to water of temperatures lower or higher than room temperature. The responses were opposite in direction between cold and warm stimuli. 6. "Anticipation" neurons (n = 4) increased their impulse discharges before the start of licking in the situation in which the animal expected access to the drinking tube. 7. "Attention" neurons (n = 2) responded to arousal stimulation such as sound, a flash of light, and body touch. These neurons showed only a slightly increasing response during ingestive behavior. 8. The locations of 56 of 90 units were histologically identified. Mechanosensitive neurons were located in the appropriate parts of the somatotopic pattern within the primary somatic sensory area in the granular cortex. Taste neurons were found evenly in the dysgranular cortex and the agranular insular cortex. Other types of neurons were located mainly in the dysgranular cortex between the granular cortex and agranular insular cortex, and some were intermingled with taste neurons in the agranular insular cortex. 9. The present study has shown that cortical neurons in the orolingual somatosensory and taste areas have different response characteristics related to each aspect of ingestive behavior.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
59.
Yoko Suda Isao Matsuo Shigeru Kuratani & Shinichi Aizawa 《Genes to cells : devoted to molecular & cellular mechanisms》1996,1(11):1031-1044
Background: We previously reported that the homozygous mutation of Otx2 gene, a mouse cognate of the Drosophila head gap gene orthodenticle , causes failure in the development of the rostral head anterior to rhombomere 3, which may correspond to earlier Otx2 expression in cells destined for the anterior mesoendoderm. At the same time, the Otx2 heterozygous mutation displayed a phenotype characterized as otocephaly, probably related to expression in the anterior neuroectoderm at the subsequent pharyngula stage. Defects were characteristic in the most anterior and posterior regions of Otx2 expression where Otx1 , another mouse cognate of orthodenticle , is not or weakly expressed. They were not found in the region where Otx1 is expressed.
Results: In the present work, Otx1 null mutant mice were generated by gene targeting in embryonic stem cells. No defects were apparent in the regionalization of the early embryonic rostral brain. The newborn brain defects were subtle and most likely related to later Otx1 -unique expression. Otx1 and Otx2 double heterozygous mutant brains, however, exhibited marked defects throughout the fore- and midbrains, where defects were not apparent with a single mutation alone.
Conclusions: Otx1 and Otx2 play synergistic roles in the development of the forebrain and midbrain where both genes are expressed. 相似文献
Results: In the present work, Otx1 null mutant mice were generated by gene targeting in embryonic stem cells. No defects were apparent in the regionalization of the early embryonic rostral brain. The newborn brain defects were subtle and most likely related to later Otx1 -unique expression. Otx1 and Otx2 double heterozygous mutant brains, however, exhibited marked defects throughout the fore- and midbrains, where defects were not apparent with a single mutation alone.
Conclusions: Otx1 and Otx2 play synergistic roles in the development of the forebrain and midbrain where both genes are expressed. 相似文献
60.
A common mutation in methylenetetrahydrofolate reductase gene among the Japanese population 总被引:7,自引:0,他引:7
Hisahide Nishio Myeong Jin Lee Motoko Fujii Kazuomi Kario Kazunori Kayaba Kazuyuki Shimada Masafumi Matsuo Kimiaki Sumino 《Journal of human genetics》1996,41(2):247-251
Summary Hyperhomocysteinemia has been reported as an independent risk factor for atherosclerotic cerebrovascular and coronary heart diseases. 5,10-Methylenetetrahydrofolate reductase (MTHFR) is one of the enzymes responsible for hyperhomocysteinemia. The C to T transition of the MTHFR gene at nucleotide position 677 results in decreasing the enzymatic activity and increasing the plasma homocysteine level. We studied the distribution of the MTHFR gene mutation among the Japanese population. The subjects were 129 Japanese males (aged 40–59 years). The allele frequency of the mutation was 0.38. The frequencies of the three genotypes were as follows: +/+, 11%; +/–, 54%; –/–, 35% (+ and – indicate the presence and absence of the mutation, respectively). We also studied the frequency of the MTHFR gene mutation in the middle-aged Japanese males with hypertension to investigate the possibility that this mutation is related to essential hypertension. The normotensive and hypertensive subjects were identical in the distribution of the mutated allele and the frequencies of the three genotypes. Furthermore, the prevalence of hypertension in each genotype group was same, although the mean diastolic pressure of the group with homozygous mutation was significantly higher than that of other groups (p<0.05). 相似文献