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1.
BACKGROUND: To understand the immunopathological features of oral lichen planus (OLP), we analyzed the expression of chemokines in the epithelial cell layers. Methods: Epithelia from OLP or healthy gingiva were collected by laser microdissection. The chemokine and chemokine receptor expressions in the epithelia were analyzed by DNA microarray. RESULTS: High levels of MIP-3alpha/LARC/CCL20 and its receptor CCR6 were expressed in the lesional epithelia. Furthermore, DC-CK1/CCL18, ELC/CCL19, SDF-1/CXCL12 and CXCR4 expressions were also increased. Immunohistologial analysis showed that high numbers of Langerhans cells (LCs) were present in the epithelia of OLP. Lesional epithelia also expressed high levels of the ligands specific for CXCR3 (e.g. MIG/CXCL9, IP-10/CXCL10 and I-TAC/CXCL11) and CCR5 (e.g. RANTES/CCL5). CONCLUSIONS: Infiltration of LCs is orchestrated by CCR6. Further, LCs residing in the lesional epithelia may be a mature phenotype. Moreover, infiltration of T cells in OLP could be mediated by signaling pathways through CXCR3 and CCR5.  相似文献   
2.
The effects of fasting on the pharmacokinetics of biperiden in rats were examined. Total clearance of biperiden was greater than 90% ascribable to hepatic clearance and was essentially blood-flow dependent. The number of compartments in the preferred pharmacokinetic model of biperiden changed from three (for normal rats) to two (for fasted rats). The smaller mean residence time (MRT) values found for fasted rats were attributable to decreases in distribution volume. Biperiden showed much higher lipophilicity than haloperidol, thiopental, and hexobarbital, and its tissue-to-plasma partition coefficient in adipose tissue was 20-fold higher than that in muscle. The influence of changes in volumes of adipose tissue and muscle on distribution volume (Vdss/BW) was evaluated from tissue-to-plasma partition coefficients. The value of Vdss/BW was predicted to decrease with decrease of adipose tissue, and to increase with decrease of muscle tissue. These results suggest that the observed decrease of Vdss/BW in fasted rats reflects reduced capacity to trap biperiden in the body, especially in adipose tissue. Possible clinical implications of these results are discussed.  相似文献   
3.
Thymidine kinase (TK) enzymes encoded by herpes simplex viruses types 1 and 2 (HSV-1, HSV-2), and equine herpesvirus type 1 (EHV-1) catalyze the phosphorylation of thymidine (dThd) and (E)-5-(2-bromovinyl)-2'-deoxyuridine (BVDU). The replication of HSV-1 is sensitive to BVDU, but the replication of HSV-2 and EHV-1 is not. To investigate the differential sensitivity of the viruses to halogenated vinyldeoxyuridine drugs, the phosphorylation of 125I-labeled (E)-5-(2-iodovinyl)-2'-deoxyuridine (IVDU) was studied. Cytosol enzymes from cells infected by HSV-2 and EHV-1 phosphorylated [125I]IVDU to the monophosphate, IVDUMP, but did not convert IVDUMP to higher di- plus triphosphates (IVDUDP plus IVDUTP) forms. In contrast, enzymes from HSV-1-infected cells converted [125I]IVDU to radioactive IVDUMP and IVDUDP plus IVDUTP. Experiments with mixtures of EHV-1- and HSV-1-induced enzymes showed that the EHV-1 enzyme did not inhibit formation of the IVDUDP plus IVDUTP by the HSV-1 enzyme. With [125I]IVDU as substrate, the Km values for the EHV-1 and HSV-1 TKs were 1.82 and 0.34 microM, respectively, and the Ki (dThd) value for the EHV-1 TK was 0.35 microM. In vivo experiments showed that HSV-1-infected cells converted IVDU to the mono- and the di- plus triphosphate forms. In contrast, EHV-1-infected cells converted IVDU to the monophosphate to a lesser extent than did HSV-1-infected cells, and did not produce the di- plus triphosphates. Thus, inefficient phosphorylation of the monophosphates probably contributes to the insensitivity of EHV-1 replication to IVDU, as it does to the insensitivity of HSV-2 replication to this drug.  相似文献   
4.
We examined the ontogeny of relaxation responses to three categories of calcium channel antagonists, represented by verapamil, diltiazem, and nifedipine, for both potential-operated (KCl-mediated) and receptor-operated channels [norepinephrine (NE)-mediated] in rat thoracic aorta. Aortic rings from 2- to 3-d, 1-wk, and 12-wk-old Sprague Dawley rats were mounted in an organ bath, bathed in Krebs' solution, and connected to a force-displacement transducer to measure isometric tension. Endothelium intact vessels at optimal passive force were exposed to a single ED50 of isotonic KCl or NE, equilibrium contraction was measured, then vessels were washed and exposed for 30 min to 1 microM verapamil, 1 microM diltiazem, or 0.1 microM nifedipine, followed by another dose of KCl or NE. Verapamil and diltiazem demonstrated significant (p less than 0.05) age-related increases in effectiveness for blocking KCl-mediated contraction [(% reduction of control contraction +/- SEM) (Verapamil: 2-3 d, 67.7 +/- 4.2; 1 wk, 72.5 +/- 1.8; 12 wk, 89.5 +/- 1.0. Diltiazem: 2-3 d, 64.6 +/- 2.9; 1 wk, 73.5 +/- 3.0; 12 wk, 83.1 +/- 1.8]. Nifedipine was equally effective at all ages: 2-3 d, 85.6 +/- 1.3; 1 wk, 90.0 +/- 1.6; and 12 wk, 91.3 +/- 1.4. Verapamil and diltiazem also showed significant age-related increases in effectiveness for blocking NE-mediated contraction (Verapamil: 2-3 d, 6.2 +/- 3.9; 1 wk, 28.0 +/- 4.8; 12 wk, 44.1 +/- 6.0. Diltiazem: 2-3 d, 8.0 +/- 3.1; 1 wk, 20.5 +/- 3.9; 12 wk, 46.5 +/- 4.8).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
5.
In seven patients undergoing right hemicolectomy for benign or malignant diseases, latero-lateral end anastomoses were made using stapling devices, LS (linear stapler) and GIA (gastrointestinal anastomosis). As no complications directly related to the anastomosis occurred, we conclude that anastomosis using stapling devices for right hemicolectomy is a safe and rapid procedure.  相似文献   
6.
Two cases of a cavernous angioma with an encapsulated intracerebral hematoma are presented. In both instances, computed tomography scan showed a ringlike appearance with a nodular lesion. Cerebral angiograms of the two cases, however, were normal. The preoperative diagnosis for both cases was a brain neoplasm. The diagnostic problems that this type of vascular malformation presents and its role in the development of the encapsulated hematoma are discussed.  相似文献   
7.
Orientia tsutsugamushi, an intracellular parasitic bacterium, comprises numerous strains of differing virulence. When BALB/c mice were infected intraperitoneally with this pathogen, a virulent strain known as Karp was found to multiply in the intraperitoneal macrophages and kill the mouse. In contrast, an avirulent strain, Kuroki, was shown to invade macrophages but be eliminated from the cells, allowing mouse survival. O. tsutsugamushi invades its host cell cytoplasm through phagocytosis and disruption of phagosomal membranes but some bacteria are then killed by phago-lysosomes within 1h of infection. Microscopic observations could not differentiate the Karp and Kuroki strains during entry and subsequent cell killing by phago-lysosomes. However, the Kuroki cells failed to divide and were markedly deformed following cytoplasmic invasion at several days post-infection. These findings suggest that macrophages have a mechanism to eliminate O. tsutsugamushi in the cytoplasm, if the invading bacteria escape phagosomal clearance, and that it is this mechanism that Kuroki does not survive. Additionally, significant levels of nitric oxide (NO) are produced in macrophages by Kuroki, but not by Karp. An NO synthase inhibitor, however, does not increase the growth of Kuroki, suggesting that NO is induced in a strain-dependent manner but does not effect proliferation.  相似文献   
8.
The catalyzed signal amplification (CSA) technique, based on the peroxidase-mediated deposition of haptenized tyramide and also known as tyramide signal amplification and catalyzed reportor deposition systems, is widely accepted as a signal amplification method for immunohistochemistry and in situ hybridization. In this study, we examined the applicability of a new simplified CSA system employing fluorescyl-tyramide (FT) to pathologic testing and research with formalin-fixed, paraffin-embedded tissues. By using the FT, instead of biotinyl-tyramide (BT) that is commonly employed in the CSA system with chromogen, nonspecific staining caused by endogenous biotin was completely avoided. The FT-CSA system loaded on the automated immunostaining equipment also allowed for more reproducible detection in short times. When applied to cyclin D1 immunostaining that is important in differentiation among small B-cell lymphomas, the system was useful in demonstrating its protein expression in mantle cell lymphomas considered negative or equivocally positive for cyclin D1 in a conventional immunodetection. In immunohistochemistry for phosphorylated proteins and murine hematologic markers that often require higher sensitivity than conventional methods, the FT-CSA system provided desirable staining results with intense signal amplification. Our results indicate that the simplified CSA system employing the FT can be useful in enlarging the target range for routine immunohistochemistry due to its high applicability.  相似文献   
9.
Aspartame (APM; L-aspartyl-L-phenylalanine methyl ester), was investigated for its ability to alter levels of the large neutral amino acids and monoamines in overnight fasted rats allowed to consume meals with or without protein for two hours. Additionally, the possible long term behavioral consequences of APM in 25% casein diets with or without 10% sucrose were determined. Acute APM ingestion increased both plasma and brain phenylalanine and tyrosine levels, but brain tryptophan levels were not altered regardless of dietary protein. Brain norepinephrine and dopamine levels were unaltered by any of the diet while serotonin levels were slightly increased when a protein-free diet was consumed. But APM and/or protein ingestion minimized this increase of brain serotonin levels as much as controls. Chronic APM ingestion failed to influence diurnal feeding patterns, meal size distributions, or diurnal patterns of spontaneous motor activity. The chronic ingestion of abuse doses of APM produced no significant chemical changes in brain capable of altering behavioral parameters believed to be controlled by monoamines in rats.  相似文献   
10.
OBJECTIVES: The purpose of the present study was to compare the effect of vitamin K(2) on cortical and cancellous bones in orchidectomized young rats. METHODS: Forty male Sprague-Dawley rats, 6 weeks of age, were randomized by stratified weight method into four groups with 10 rats in each group: baseline controls (BLC), age-matched controls (AMC), orchidectomy (ORX), and ORX+vitamin K(2) administration (K). Vitamin K(2) (menatetrenone) was administered subcutaneously twice a week at dose of 30 mg/kg each. The experimental period was 8 weeks, and cortical and cancellous bone histomorphometry was performed on the tibial shaft and the proximal tibia, respectively. RESULTS: Cortical area (Ct Ar) and cancellous bone volume (BV/TV) were significantly greater in the AMC group than in the BLC group. Ct Ar was significantly lower in the ORX group than in the AMC group, and cancellous BV/TV was also significantly lower in the ORX group than in the AMC group as a result of significantly increased eroded surface (ES/BS). Although Ct Ar in the ORX+K group did not differ significantly from that in the ORX group, cancellous BV/TV was significantly greater in the ORX+K group than in the ORX group, but still significantly lower than in the AMC group. This protective effect of vitamin K(2) on cancellous bone was attributable to normalizing increased ES/BS. CONCLUSIONS: Vitamin K(2) appears to act more strongly on cancellous bone than on cortical bone in ORX young rats. High dose vitamin K(2) could partially prevent the reduction of cancellous bone gain by normalizing raised bone resorption in ORX young rats.  相似文献   
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