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1.
The alphavbeta6 integrin is an exclusively epithelial integrin that is highly expressed during fetal development. In adult tissue, alphavbeta6 integrin is expressed during inflammation, carcinogenesis, and in wound healing. We previously reported that alphavbeta6 integrin is highly expressed in poorly healing human wounds and its over-expression is associated with chronic wounds in a mouse model. The objective of this study was to investigate the role of alphavbeta6 integrin in compromised wound healing induced by hydrocortisone treatment or aging by using young and old mice deficient in or overexpressing the beta6 integrin subunit in the epidermis. Untreated aged beta6 integrin-deficient (beta6-/-) animals showed a significant delay in wound healing when compared to their age-matched controls or younger beta6-/- mice. The most significant delay was observed at the stages where granulation tissue deposition was occurring. Hydrocortisone treatment significantly delayed wound healing in wild-type and beta6 integrin-deficient mice in comparison with the untreated controls. However, hydrocortisone treatment in beta6 integrin overexpressing animals did not cause a significant delay in wound healing. The results of this study suggest that alphavbeta6 integrin plays an important role in wound healing in animals compromised by either age or stress mimicked by hydrocortisone.  相似文献   
2.
Activities of the xenobiotic metabolizing enzymes were measured in the liver, kidney, duodenum and lung microsomes and cytosol fractions of Wistar rats after subchronic administration of 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX), a potent bacterial mutagen in chlorinated drinking water. MX was administered by gavage at the dose level of 30 mg/kg for 18 weeks (low dose), or at the dose level which was raised gradually from 45 mg/kg for 7 weeks via 60 mg/kg for 2 weeks to a clearly toxic dose of 75 mg/kg for 5 weeks (high dose). Microsomal and cytosolic preparations were made and the activities of 7-ethoxyresorufin-O-deethylase (EROD), pentoxyresorufin-O-dealkylase (PROD), NADPH-cytochrome-c-reductase, UDP-glucuronosyltransferase (UDPGT) and glutathione-S-transferase (GST) were measured. Kidneys were affected most. A dose-dependent decrease was observed in EROD (90% in males, 80% in females at the high dose) and in PROD (58% in females, at the high dose) in kidneys. An increase was, however, detected in kidney NADPH-cytochrome-c-reductase (66% in females at high dose), UDPGT (89% in males and 97% in females at high dose) and GST activities (56% in males and 50% in females at high dose). MX caused only a few changes in the enzyme activities of the liver. The EROD activity was decreased 25% to 37%, both in the livers of males and females, but the total content of P450s was not altered. Hepatic GST activity was elevated in females in a dose-dependent manner (31% and 44%). GST activity was elevated in duodenum in females (59%) at the high dose. There were no marked changes in the enzyme activities in the lungs. MX was a weak inhibitor of EROD activity both in the liver and kidney microsomes in vitro, decreasing the EROD activity by 53% and 43%, respectively at the concentration of 0.9 mM. The results indicate that MX decreases the activity of phase I metabolism enzymes, but induces phase II conjugation enzyme activities, particularly in kidneys in vivo. It is possible that these changes contribute to metabolism of MX in kidneys and renders them susceptible to MX in the course of repeated exposure.  相似文献   
3.
The alcohol-preferring AA rats have higher concentration of 5-hydroxytryptamine (5-HT) in the brain than the alcohol-avoiding ANA rats. In the present study, the 5-HT1, 5-HT2, and 5-HT3 receptors were studied with [3H]5-HT, [3H]ketanserin, and [3H]LY278584, respectively, in membrane homogenates from different brain regions of both rat lines using in vitro binding assays. No differences in the 5-HT1 and 5-HT2 receptor binding in the brainstem, hippocampus, frontal cortex, and hypothalamus or in the 5-HT3 receptor binding in the nucleus accumbens, amygdala, hippocampus, and frontal cortex were observed between the ethanol-naive animals of the rat lines. In rats given the opportunity to voluntarily consume alcohol, there was a tendency to increase 5-HT1 binding in the ANA rats, which tendency was, however, also found in their ethanol-naive controls subjected to the same handling and behavioral tests as the ethanol-experienced animals. The results do not, however, indicate that any genetic modifications of the 5-HT receptor-binding sites have occurred in the process of the selective breeding of AA and ANA rats for alcohol preference and avoidance, respectively.  相似文献   
4.
The stability of 18 batches of anti-D immunoglobulin preparations from 7 European manufacturers was studied over 28-day incubation at +37 degrees C and 3-year storage at +4 degrees C. The mean loss of activity after 28 days at +37 degrees C was 12.3 +/- 8.2%, and after 3 years at +4 degrees C 15.2 +/- 9.5%. The correlation coefficient of the loss of activity between these two storages was r = 0.61, p less than 0.05 indicating that short-term incubation can be used to evaluate the shelf life stability of anti-D activity. In general, measurements of IgG fragments or activities of plasmin, plasminogen, or prekallikrein activator were not valuable in predicting the stability of anti-D activity due to the fact that the preparation of each manufacturer has its own unique pattern of enzymes and inhibitors. The anti-D immunoglobulin preparations contained up to at least 7 plasma proteins in addition to IgG. All preparations contained factor B, most of them alpha 2-macroglobulin, alpha 1-antitrypsin, albumin, and alpha 2-HS glycoprotein, alpha-Lysozyme was present in 7, and ceruloplasmin in 2 preparations. Neither purity nor impurity correlated with stability.  相似文献   
5.
The aim of the present study was to describe the cases of occupational asthma (OA) due to stainless steel welding fumes diagnosed at the Finnish Institute of Occupational Health during the period 1994-2003. OA was diagnosed according to patient history, lung function examinations and welding challenge tests with measurements of the forced expiratory volume in one second (FEV(1)) and peak expiratory flow (PEF) values. The present series comprised 34 patients, all male, with a mean age of 44.7 yrs (range 22-57), mainly working as welders. The mean duration of exposure was 22.4 yrs, and the mean duration of exposure before the onset of respiratory symptoms was 18 yrs. Dyspnoea was the most frequently reported work-related respiratory symptom. During the inhalation challenge tests, the mode of the asthmatic FEV(1)/PEF reaction was delayed in 16 (47%) patients, immediate in nine (26%) patients and dual (both immediate and delayed) in nine (26%) patients. In the follow-up assessment 6 months later, only six patients were considered able to continue performing welding tasks, whereas occupational injury pension was recommended for seven, and measures of vocational rehabilitation for 14 patients. In most cases, after the diagnosis of occupational asthma, the continuation of welding work was not possible.  相似文献   
6.
Depression-executive dysfunction syndrome in stroke patients.   总被引:6,自引:0,他引:6  
OBJECTIVE: It has been suggested that executive dysfunction could be the core defect in patients with geriatric or vascular depression, and that this depression-dysexecutive syndrome (DES) might be related to frontal-subcortical circuit dysfunction. The authors tested this hypothesis in 158 poststroke patients, of whom 21 had both depression and executive dysfunction. Methods: In this cross-sectional cohort study, a neurological, psychiatric, and neuropsychological examination was carried out 3 months after ischemic stroke, and brain infarcts, white-matter changes, and brain atrophy were recorded by MRI. RESULTS: The 21 patients with DES had significantly more brain infarcts affecting their frontal-subcortical circuit structures than the 137 patients without DES, or the 41 patients with depression but without executive dysfunction. Patients with DES also had more severe depressive symptoms and worse psychosocial functioning, and they coped less well in complex activities of daily living. CONCLUSIONS: DES is a valid concept and may define a subgroup of poststroke patients with frontal-subcortical pathology and with distinct prognosis and treatment options.  相似文献   
7.

Background  

Movement control dysfunction [MCD] reduces active control of movements. Patients with MCD might form an important subgroup among patients with non specific low back pain. The diagnosis is based on the observation of active movements. Although widely used clinically, only a few studies have been performed to determine the test reliability. The aim of this study was to determine the inter- and intra-observer reliability of movement control dysfunction tests of the lumbar spine.  相似文献   
8.
A new COMT inhibitor, nitecapone (OR-462) or clorgyline, a MAO-A inhibitor, was infused into the 3rd brain ventricle (i.c.v.) of conscious male rats. None of the enzyme inhibitors given alone alter hypothalamic or striatal levels of L-dopa, dopamine or their metabolites. Most of the rats were pretreated with levodopa/carbidopa (LD/CD, 15/30 mg kg-1 intraperitoneally). Now, the action of nitecapone is localized in the hypothalamus since homovanillic acid (HVA) is decreased there, not in the striatum. The levels of 3-O-methyldopa (3-OMD) are not changed in either brain region, suggesting a lack of the peripheral leakage of nitecapone. Clorgyline (3 and 10 micrograms rat-1) elevates hypothalamic and dopamine levels. Nitecapone and clorgyline decrease prolactin (PRL) levels below those reduced by LD/CD treatment.  相似文献   
9.
Abstract The treatment-mix, treatment time, and dental status of 268 male industrial workers entitled to employer-provided dental care were studied. The data were collected from treatment records of the covered workers over the 5-year period 1989-93. Treatment time was based on clinical treatment time recorded per patient visit, and the treatment procedure codes were reclassified into a treatment-mix according to American Dental Association categories, with a modification combining endodontics and restorative treatment. The mean number of check-ups followed by prescribed treatment (treatment courses) during the 5 years was 3.7 among those who had entered the in-house dental care program prior to the monitored period (old attenders). Their treatment time was stable, 57–63 min per year, while the first-year mean treatment time (170 min) of those who had entered the program during the study period (new attenders) was significantly higher (P<0.01) than the 5-year mean of the old attenders (61 min). Over the first 2 years, the treatment-mix of the new attenders showed a rise in diagnostic and preventive procedures from one-third to about one-half of all procedures, as it was for the old attenders. The new attenders' mean number of carious teeth (2.7), registered at the initial check-up visit, paralleled the mean recently demonstrated in the similar non-covered population. It was significantly higher than the 5-year mean of the old attenders (0.5) (P<0.001), but declined to the same level after the first year of treatment. It was concluded that the studied program seemed to contribute to a stabilization of treatment-mix, and to the establishment of a shorter annual treatment time within the first 2 years of treatment.  相似文献   
10.
A novel chemical etching method was recently developed to create a controlled microrough surface on porous bioactive glass implants. Our earlier in vitro studies showed enhanced attachment of osteoblast-like MG63 cells on a microrough bioactive glass surface. The purpose of our current study was to confirm the in vivo significance of surface microroughening for bone bonding of bioactive glass. Porous bioactive glass cones made of sintered microspheres were surgically implanted in the anterior cortex of rabbit femurs. Peripheral quantitative computed tomography (pQCT), biomechanical push-out testing, histomorphometry, and electron microscopy (BEI-SEM) were used to analyze bone ingrowth and osseointegration at 7, 10, 14, 28, 56, and 84 days after implantation. The results showed that microroughening of the bioactive glass surface significantly enhanced the bone-bonding response of the biomaterial. The positive response was seen in one of the three bioactive glass compositions studied. The affinity index of new bone on the glass surface was significantly (p = 0.02) increased with a trend (p = 0.10) toward improved mechanical incorporation. New bone formation was dependent on the glass composition, and it was found to occur not only through the mechanism of bone ingrowth but also based on in situ osteogenesis within implant interstices. Based on these results, the procedure of microroughening could enhance the osteopromotive properties of certain bioactive glass compositions.  相似文献   
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