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61.
62.
BACKGROUND: The Paigen method has detected not only persistently galactosemic patients, but also many children with transient galactosemia during the neonatal period. The diagnosis and clinical course of 389 patients with transient galactosemia detected by neonatal mass-screening from 1986 to 1996 in the Hiroshima prefecture were evaluated. METHODS: Enzyme assays for galactose metabolism, measurement of blood galactose levels, erythrocyte galactose-1-phosphate levels, serum total bile acid (TBA) levels and liver function tests were performed at the first visit by patients to our hospital. Liver function and the mental and physical development of patients were evaluated during the follow-up period (approximately 1 year). RESULTS: The diagnoses were classified as follows: 253 patients with unknown cause, 128 heterozygotes and two homozygotes for galactose enzyme deficiency (galactose-1-phosphate uridyltransferase, galactokinase, UDP-galactose 4-epimerase) and six heterozygotes for Duarte variant. Twelve patients showed high serum levels of TBA (> 80 mumol/L), which suggests the presence of portal-systemic shunts during the neonatal period causing galactosemia. Most patients showed normal mental and physical development during infancy. However, of 25 patients with mild to moderate abnormal liver function tests of unknown etiology after the neonatal period, five showed poor weight gain coincident with liver dysfunction. In almost all patients, levels of transferase decreased to the normal range by 1 year of age. CONCLUSION: We found that the prognosis of transient galactosemia was almost always favorable. However, patients should be followed for at least 1 year, because late liver dysfunction, which might cause poor weight gain, occurred in 6% of our patients.  相似文献   
63.
Elevated expression of interleukin (IL)-18 mRNA and protein in intestinal mucosa, attributable to activated monocytes and macrophages in that site, has been reported in patients with inflammatory bowel disease (IBD). However, changes in serum IL-18 concentrations in patients with IBD have not been reported. We measured bioactive IL-18 in serum from patients with IBD, using an enzyme-linked immunosorbent assay (ELISA). Mean serum IL-18 concentrations in 5 patients with Crohn disease (CD) were 400 pg/mL, approximately 1.7 times higher than concentrations in 21 control subjects (p < 0.01). However, serum IL-18 was not increased in patients with ulcerative colitis (UC). These results suggest that like other T-helper type 1 (Th1) cytokines IL-18 may play a key pathogenetic role in Th1-mediated disorders, such as CD. Regulation and expression of IL-18 appears to differ between CD and UC, and serum IL-18 may be a useful clinical marker for CD.  相似文献   
64.
Background  Surgical stress is known to affect body temperature, white blood cell (WBC) count, C-reactive protein (CRP), and interleukin-6 (IL-6). The aim of the present study was to investigate which parameter is most suitable for quantitative analysis of surgical stress. Methods  Unilateral total knee arthroplasty (U-TKA) and bilateral TKA (B-TKA) were selected for the subjects of this study because the B-TKA creates approximately double the surgical stress of the U-TKA. The temperature, WBC count, CRP, and IL-6 in the blood were measured pre- and postoperatively in both groups. The IL-6 in the drainage fluid was also measured after the operation. Results  The temperature, WBC count, CRP, and IL-6 in the blood significantly increased on the first day after the operation in both groups. There were significant differences between the two groups in the WBC count (P < 0.05) and the IL-6 level in the blood (P < 0.05) on the first day after the surgery. There were no significant differences between the two groups for the CRP and IL-6 levels in the drainage fluid. The relative proportions — (B-TKA/U-TKA) × 100 (%) — were 170.4% for the operating time, 219.4 % for total blood loss, 200.0% for blood transfusion, 100.3% for temperature, 128.9% for WBC count, 127.4% for CRP, and 246.5% for the IL-6 level in the blood. Conclusions  The serum IL-6 level may best reflect surgical stress and could therefore be a quantitative marker of surgical stress.  相似文献   
65.
Diffusely infiltrating gliomas are the most common type of primary intracranial neoplasm in humans. One of the major obstacles to the effective treatment of these tumors is their highly infiltrative growth. However, mechanisms controlling their migration and proliferation are poorly understood. Glioma cells resemble neural progenitors, and we hypothesize that gliomas recapitulate the capacity of migration and proliferation of progenitors that takes place during brain development. Based on recent evidence implicating cytoplasmic dynein and its regulatory proteins in neural progenitor migration and division, we conducted immunohistochemical evaluation of surgically resected human glioma samples for the presence and distribution of these proteins. We examined expression of LIS1, the gene responsible for type I lissencephaly, cytoplasmic dynein and the dynein- and LIS1-interacting factors dynactin, NudE/NudEL and NudC, which play significant roles in neural progenitor cell behavior. We found that each of these proteins is expressed in all histological types and grades of human neuroectodermal tumors examined. Immunohistochemical analysis revealed that the levels of expression varied from cell to cell within each tumor, ranging from very high to undetectable. This stands in contrast to the low levels of diffuse staining seen in non-neoplastic brain tissue. Of particular interest, we noted tumor cells infiltrating the white matter and tumor cells undergoing cell division amongst the cells with notably high expression levels. These findings are compatible with the idea that LIS1 and its interacting proteins play a role in glioma migration and proliferation analogous to their role during brain development. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. This work was supported in part by a Grant-in-Aid for Scientific Research (no. 16500202) from the Japanese Ministry of Education, Culture, Sports, Science and Technology to SOS and NIH grant HD40182 to RBV.  相似文献   
66.
This report describes a new surface-treatment technique for cell micropatterning. Cell attachment was selectively controlled on the glass surface using a photochemical reaction. This strategy is based on combining 2-methacryloyloxyethyl phosphorylcholine (MPC) polymer, which is known to reduce non-specific adsorption, and a photolabile linker (PL) for selective cell patterning. The MPC polymer was coated directly on the glass surface using a straightforward surface modification method, and was removed by ultraviolet (UV) light illumination. All the surface modification steps were evaluated using static water contact angle measurements, X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), measurements of non-specific protein adsorption, and the cell attachment test. After selective cleavage of the MPC polymer through the photomask, cells attached only to the UV-illuminated region where the MPC polymer was removed, which made the hydrophilic surface relatively hydrophobic. Furthermore, the size of the MC-3T3 E1 cell patterns could be controlled by single cell level. Stability of the cell micropatterns was demonstrated by culturing MC-3T3 E1 cell patterns for 5 weeks on glass slide. The micropatterns were stable during culturing; cell viability also was verified. This method can be a powerful tool for cell patterning research.  相似文献   
67.
68.
Effects of prostaglandin E1 on vascular ATP-sensitive potassium channels   总被引:2,自引:0,他引:2  
BACKGROUND: Prostaglandin E1 (PGE1) has been reported to activate ATP-sensitive potassium (KATP) channels, which induces vasorelaxation. However, direct evidence of PGE1 interactions with vascular KATP channels is limited. METHODS: The present study investigated the effects and mechanisms of PGE1 on vascular KATP channels in both isometric tension and patch clamp experiments.Isometric tension experiments were performed in rat thoracic aortic rings without an endothelium. Electrophysiologic experiments were performed using patch-clamp techniques to monitor KATP channels in rat vascular smooth muscle cells. RESULTS: PGE1 significantly decreased the isometric tension in a concentration-dependent manner, which was partially inhibited by pretreating with a KATP channel inhibitor, glibenclamide (1 microM), or an inhibitor of protein kinase A (PKA), Rp-cAMPS (100 microM). Application of PGE1 to the bath solution during cell-attached recordings induced a significant increase in KATP channel activity, whereas PGE1 failed to activate KATP channels in the inside-out patches. The PGE1-induced KATP channel currents in cell-attached patches were abolished by pretreating with Rp-cAMPS (100 microM). CONCLUSIONS: The results indicate that the activation of vascular KATP channels played an important role in the PKA-dependent PGE1-induced vasorelaxation. Furthermore, an electrophysiological experiment demonstrated that PGE1 activated vascular KATP channels via PKA activation.  相似文献   
69.
Recent evidence suggests a crosstalk between angiotensin II (Ang II) and insulin. However, whether this crosstalk affects glucose uptake, particularly in terms of actin filament involvement, has not yet been studied in vascular smooth muscle cells. Pretreatment of cells with either Ang II or cytochalasin D disarranged actin filaments in a time-dependent manner and inhibited glucose uptake. However, insulin increased actin reorganization and glucose uptake. Membrane fractionation studies showed that Ang II decreased GLUT-1 at the cell membrane, whereas it increased GLUT-1 in the cytoplasm, indicating that Ang II may cause internalization of GLUT-1 via actin disorganization, consequently decreasing glucose uptake. The effects of Ang II on glucose uptake and actin reorganization were blocked by AT1 receptor antagonist, but not by AT2 antagonist. Either P38 or ERK1/2 inhibitors partially reversed the Ang II-inhibited actin reorganization and glucose uptake, suggesting that MAPK signaling pathways could be involved as downstream events in Ang II signaling, and this signaling may interfere with insulin-induced actin reorganization and glucose uptake. These data imply that Ang II induces insulin resistance by decreasing glucose uptake via disarrangement of actin filaments, which provides a novel insight into understanding of insulin resistance by Ang II at the molecular level.  相似文献   
70.
1. The present study was designed to examine the role of amlodipine in preventing and reversing monocrotaline (MCT)-induced pulmonary arterial hypertension (PAH) in rats. 2. Rats were injected with MCT (40 mg/kg, s.c.) and randomly given either 6 mg/kg per day of amlodipine in drinking water or placebo for 3 weeks. Any animals treated with MCT that survived for 3 weeks were given either amlodipine or placebo for the next 3 weeks. 3. Blood pressure was not different between the groups. Amlodipine immediately following MCT markedly inhibited PAH with severe pulmonary vascular remodelling. The survival rate at 3 weeks after treatment was increased significantly in the amlodipine group compared with the placebo group (77%vs 43%; P < 0.01). The placebo group showed markedly diminished expression of endothelial nitric oxide synthase (eNOS) protein and mRNA levels, increased numbers of proliferating cell nuclear antigen-positive cells, enhanced mRNA expression of matrix metalloproteinase-2 and pro-inflammatory cytokines in the lung tissue and upregulation of P-selectin on the endothelium of the pulmonary arteries, whereas these effects were suppressed in the amlodipine-treated group. Furthermore, late treatment with amlodipine did not palliate PAH or improve survival. 4. Amlodipine inhibited the development of PAH and improved survival in rats independent of its effect on lowering blood pressure. These effects were associated with marked inhibition of the downregulation of eNOS and improvement of pulmonary vascular endothelial activation, as well as anti-inflammatory, antiproliferative and antifibrotic effects in the lung tissue. However, amlodipine failed to reverse established PAH. This study may provide an insight into therapeutic strategy of amlodipine in PAH.  相似文献   
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