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1.
The migration of leukocytes into inflamed peripheral tissues and lymphoid organs involves a cascade of molecular events finely regulated by cell adhesion molecules and chemokines. Fractalkine/CX3CL1 is a membrane-bound chemokine that functions not only as a chemoattractant but also as an adhesion molecule, and is expressed on endothelial cells activated by proinflammatory cytokines. The fractalkine receptor, CX3CR1, is expressed on cytotoxic effector lymphocytes including NK cells and cytotoxic effector T cells (T(CE)), mature monocytes/macrophages, and mucosal dendritic cells, all of which play important roles in elimination of pathogens and cancer cells. Recently, accumulating evidence in both clinical studies and animal disease models has shown that fractalkine is also involved in the pathogenesis of various chronic inflammatory diseases, such as rheumatoid arthritis and atherosclerosis. This article reviews the unique functions of fractalkine and its pathophysiological roles in various clinical conditions.  相似文献   
2.
We investigated the temporal and spatial expression of transforming growth factor-β in the healing patellar ligament of the rat by immunohistochemistry. The mid-portion of the medial half of the patellar ligament in 14-week-old male Wistar rats was cut transversely with a scalpel. On day 1 after ligament injury, diffuse staining for transforming growth factor-β was observed in the extracellular matrix filling the wound, and the staining in the adjacent ligament tissue was as weak as it was in the normal ligament. On day 3, the intensity of the diffuse extracellular staining decreased, and the staining was observed in correspondence with the cellular distribution in the wound site and in the adjacent uninjured ligament tissue. On day 7, the intense staining was widely distributed over the whole length of the ligament tissue. On day 28, the staining for transforming growth factor-β was still observed at the wound site and in the adjacent uninjured ligament tissue, where the staining was reduced in intensity but still stronger than it was in the normal ligament. On day 56, the expression of transforming growth factor-β was still detectable at the wound site: however, in the adjacent uninjured ligament tissue, it had almost subsided to the normal level. The results of the present study suggest that ligament healing may be accompanied by extensive changes in the expression of transforming growth factor-β over the whole length of ligament tissue.  相似文献   
3.
To elucidate the penetrability of carteolol, a β-adrenoceptor antagonist (β-blocker) into the brain of rats, intracerebral and serum concentrations of the compound were determined in male rats receiving single or repetitive oral administration of carteolol hydrochloride at 30 mg/kg. The time-course of the intracerebral concentration of carteolol following single IV administration of the compound at 10 and 30 mg/kg was also studied in male rats. A high-performance liquid chromatography method was used to determine the intracerebral and serum concentrations. Following single oral dosing, the intracerebral concentration of carteolol reached a maximum of 0.074 μg/g at 2 h postdosing and declined with a half-life of 3.7 h, and the Cmax and AUC of carteolol in the brain were 12.5% and 19.8% of those in serum. The intracerebral and serum concentrations of carteolol were determined in male rats receiving repetitive oral dosing of the compound once daily for 7 days. The concentration of carteolol in the brain and serum at 1 h postdosing varied within a range of 0.059–0.091 μg/g and 0.321–0.443 μg/ml, respectively, throughout the dosing period, showing no changes in the penetrability of the compound into the brain due to repeated dosing. The concentration of carteolol in the brain and serum increased in a dose-dependent manner in rats receiving a single IV administration of the compound. The elimination half-life of carteolol in the serum and brain was 0.6–0.8 h and 1.3–1.7 h, respectively, in rats following single IV dosing of the compound. The half-life in the brain was about twice as long as that in the serum. The brain to serum concentration ratio was 0.306:0.499. From the above results, it was concluded that carteolol is distributed from the circulation to the brain with low penetrability. Received: 30 October 1996/Final version: 16 December 1996  相似文献   
4.
5.
Hemodynamic states of portal hypertension with esophageal varices were studied by scintiphoto splenoportography (SSP) and left gastric angiographies in relation to endoscopic findings. The cases were classified into two groups by SSP. The flow of left gastric vein was hepatofugal in Group I (77.3%), and it was hepatopetal or "to and fro" in Group II (22.7%). Endoscopically, the varices were more severe in Group I than those in Group II. The diameter of left gastric vein was significantly larger in Group I. The values of K.ICG and liver function by blood analysis were also poor in Group I. Moreover, the cases with varices supplied by both left gastric artery and vein showed more severe endoscopic findings and history of hematemesis than those in the cases with varices supplied by left gastric artery alone. In conclusion, the results suggested that the flow of left gastric vein was closely related to the severity of esophageal varices.  相似文献   
6.
IntroductionSex differences have already been reported in sub‐Saharan Africa for attrition and immunological response after antiretroviral therapy (ART) initiation, but follow‐up was usually limited to the first two to three years after ART initiation. We evaluated sex differences on the same outcomes in the 10 years following ART initiation in West African adults.MethodsWe used cohort data of patients included in the IeDEA West Africa collaboration, who initiated ART between 2002 and 2014. We modelled no‐follow‐up and 10‐year attrition risks, and immunological response by sex using logistic regression analysis, survival analysis with random effect and linear mixed models respectively.ResultsA total of 71,283 patients (65.8% women) contributed to 310,007 person‐years of follow‐up in 16 clinics in eight West African countries. The cumulative attrition incidence at 10‐year after ART initiation reached 75% and 68% for men and women respectively. Being male was associated with an increased risk of no follow‐up after starting ART (5.1% vs. 4.0%, adjusted Odds Ratio: 1.25 [95% CI: 1.15 to 1.35]) and of 10‐year attrition throughout the 10‐year period following ART initiation: adjusted Hazard Ratios were 1.22 [95% CI: 1.17 to 1.27], 1.08 [95% CI: 1.04 to 1.12] and 1.04 [95% CI: 1.01 to 1.08] during year 1, years 2 to 4 and 5 to 10 respectively. A better immunological response was achieved by women than men: monthly CD4 gain was 30.2 and 28.3 cells/mL in the first four months and 2.6 and 1.9 cells/μL thereafter. Ultimately, women reached the average threshold of 500 CD4 cells/μL in their sixth year of follow‐up, whereas men failed to reach it even at the end of the 10‐year follow‐up period. The proportion of patients reaching the threshold was much higher in women than in men after 10 years since ART initiation (65% vs. 44%).ConclusionsIn West Africa, attrition is unacceptably high in both sexes. Men are more vulnerable than women on both attrition and immunological response to ART in the 10 years following ART initiation. Innovative tracing strategies that are sex‐adapted are needed for patients in care to monitor attrition, detect early high‐risk groups so that they can stay in care with a durably controlled infection.  相似文献   
7.
We found the association of a heterozygous novel MPZ gene point mutation, Ile62Phe in exon 2, with autosomal dominant motor and sensory neuropathy with focally folded myelin sheaths. Family study revealed that de novo Ile62Phe mutation on the MPZ gene occurred in the proband and was inherited by her children with early onset slowly progressive neuropathy. Our study suggests that the characteristic pathologic findings of the sural nerve in these patients are closely related to the site and nature of amino acid substitutions of the MPZ gene.  相似文献   
8.
The progression of cellular repopulation and collagen synthesis in fresh-frozen rat patellar tendon allografts was investigated by means of indirect immunofluorescence histologic analysis and electron microscopic techniques for 8 weeks after transplantation. In each of 10 procedures, the medial half of the patellar tendon with a tibial bone block was harvested from a Wistar rat and transplanted into a corresponding defect in the medial patellar tendon of a Lewis rat. Actin filaments in the repopulating cells and newly synthesized collagen fibrils in the graft were identified with rhodamine-phalloidin stain and with a polyclonal antibody against type III collagen aminopropeptide. On the first day after transplantation, no specific fluorescence was detected in the graft. One week later, specific labeling for fibrillar-actin (F-actin) and type III collagen aminopropeptide was detected in an area extending from the adjacent granulation tissue into the proximal end of the graft. F-actin and type III collagen aminopropeptide were aligned along the longitudinal axis of the graft and extended from the proximal suture site toward the distal portion. Two weeks after transplantation, fibrillar labeling for F-actin and type III collagen amino-propeptide showed that remodeling had extended to the midportion of the graft. Labeling throughout the entire graft was detected 4 weeks after transplantation. During the entire remodeling process, the repopulated fibroblasts consistently retained their elongated shape and their alignment with the longitudinal axis of the graft. The cells developed well-organized actin bundles at their peripheries, which identified them as having a myofibroblast phenotype. Immunofluorescence detection for type III collagen aminopropeptide also showed consistent alignment parallel to the longitudinal axis of the graft and a fibrillar arrangement. Electron microscopy revealed thinner collagen fibrils in the vicinity of the fibroblasts, which were aligned in the direction of the actin bundles. These results indicate that, during the early remodeling phase, collagen synthesis and deposition in the graft proceeds while the original alignment of the graft matrix is preserved. The close association between the alignment of actin bundles in repopulated "myofibroblastic" cells and that of newly synthesized collagen fibrils along the lines of the graft matrix may represent evidence of force transmission between the actin cytoskeleton and the linking extracellular matrix in vivo.  相似文献   
9.
We investigated the localization and extent of beta-amyloid precursor protein (APP) immunoreactivity as a sensitive marker for impairment of fast axonal transport in the spinal cords of patients with HTLV-I-associated myelopathy (HAM)/tropical spastic paraparesis (TSP). The results from this study show that APP, used as a marker of early axonal damage in HAM/TSP lesions, is more intensively expressed in areas of active-inflammatory lesions than those of inactive-chronic lesions. The close localization to the areas containing inflammation (activation of macrophage/microglia) is striking and suggests that axonal damage is closely associated with inflammation in active-chronic lesions. Although inflammatory cell infiltration in the central nervous system (CNS) is rarely found in inactive-chronic lesions, a few clusters of APP+ axons are found in the spinal cord white matter in some cases. The presence of APP+ axons without relation to inflammatory cells in inactive-chronic lesions, suggest that soluble neurotoxic factors might induce axonal changes in the CNS of HAM/TSP. The occasional myelinated fibers in the anterior and posterior spinal roots in lower thoracic to lumbar levels had APP+ axons, suggesting that spinal nerve roots can be affected in HAM/TSP, especially in lower thoracic to lumbar levels. Impairment of fast axonal transport may contribute to the development of disability in patients with HAM/TSP.  相似文献   
10.
Warm ischemia and reperfusion injury in diet-induced canine fatty livers   总被引:3,自引:0,他引:3  
BACKGROUND: Fatty liver is associated with primary nonfunction after liver transplantation, contributing a shortage of suitable liver grafts. Because extensive investigation of mechanisms underlying such nonfunction has been limited largely to rodents, we made a new fatty liver model in dogs and studied primary nonfunction after warm ischemia. METHODS: We developed a diet rich in fat but deficient in choline to induce fatty change in canine liver and investigated effects of 60 min of warm ischemia and reperfusion in dogs with such fatty livers. RESULTS: Microscopically evident steatosis increased with duration of dietary manipulation (up to 12 weeks), as did hepatic total lipid and triglyceride levels. No dog with >30% of steatotic hepatocytes, >445 mg/g hepatic total lipid or >145 mg/g hepatic triglyceride survived after 60 min of warm ischemia. Arterial ketone body ratios decreased and blood endotoxin increased after reperfusion in nonsurvivors. The main histologic finding in livers of nonsurvivors was marked sinusoidal congestion. CONCLUSIONS: Damage to hepatocytes and nonparenchymal cells after warm ischemia and reperfusion was thought to be closely related to sinusoidal microcirculatory disturbances in fatty livers. The canine fatty liver model reported here may be useful in studying the pathology of primary nonfunction and in establishing criteria for allowable degrees of fatty change in potential liver grafts.  相似文献   
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