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51.
Essential role for CD103 in the T cell-mediated regulation of experimental colitis 总被引:12,自引:0,他引:12 下载免费PDF全文
Annacker O Coombes JL Malmstrom V Uhlig HH Bourne T Johansson-Lindbom B Agace WW Parker CM Powrie F 《The Journal of experimental medicine》2005,202(8):1051-1061
The integrin CD103 is highly expressed at mucosal sites, but its role in mucosal immune regulation remains poorly understood. We have analyzed the functional role of CD103 in intestinal immune regulation using the T cell transfer model of colitis. Our results show no mandatory role for CD103 expression on T cells for either the development or CD4+CD25+ regulatory T (T reg) cell-mediated control of colitis. However, wild-type CD4+CD25+ T cells were unable to prevent colitis in immune-deficient recipients lacking CD103, demonstrating a nonredundant functional role for CD103 on host cells in T reg cell-mediated intestinal immune regulation. Non-T cell expression of CD103 is restricted primarily to CD11c(high)MHC class II(high) dendritic cells (DCs). This DC population is present at a high frequency in the gut-associated lymphoid tissue and appears to mediate a distinct functional role. Thus, CD103+ DCs, but not their CD103- counterparts, promoted expression of the gut-homing receptor CCR9 on T cells. Conversely, CD103- DCs promoted the differentiation of IFN-gamma-producing T cells. Collectively, these data suggest that CD103+ and CD103- DCs represent functionally distinct subsets and that CD103 expression on DCs influences the balance between effector and regulatory T cell activity in the intestine. 相似文献
52.
M. Martineau G. Papacleovoulou S. Abu-Hayyeh P.H. Dixon H. Ji R. Powrie L. Larson E.K. Chien C. Williamson 《Placenta》2014
Introduction
Intrahepatic Cholestasis of Pregnancy (ICP) is associated with an increased risk of fetal morbidity and mortality and is characterised by elevated bile acids in the maternal and fetal compartments. Bile acids have been shown to attenuate renal 11βHSD2 expression and, given the protective role of placental 11βHSD2 in preventing fetal exposure to excessive maternal cortisol, we aimed to establish whether raised serum bile acids in ICP influence placental 11βHSD2 expression.Methods
Placental tissue from human and murine cholestatic pregnancy was evaluated for changes in 11βHSD2 mRNA expression compared to uncomplicated pregnancy using quantitative PCR. Parallel in vitro studies were performed using BeWo choriocarcinoma cells to assess the effect of different bile acid species on 11βHSD2 gene expression and whether concurrent UDCA administration can reverse any bile acid induced changes.Results
Placental 11βHSD2 mRNA expression was reduced in human and murine cholestatic pregnancy. In BeWo cells, treatment with the primary bile acid CDCA resulted in reduced 11βHSD2 gene expression, while treatment with other primary bile acids had no significant effect. Furthermore, the tertiary bile acid UDCA, used in the treatment of ICP did not significantly affect 11βHSD2 mRNA levels either alone, or when co-administered with CDCA.Discussion
Under cholestatic conditions placental 11βHSD2 mRNA is reduced. Studies in BeWo choriocarcinoma cells demonstrated that CDCA is likely to be the specific bile acid that mediates this effect. UDCA, the main bile acid used to treat cholestasis, did not reduce placental 11βHSD2 expression, further supporting its use in the management of ICP. 相似文献53.
Kersten MJ; Evers LM; Dellemijn PL; van den Berg H; Portegies P; Hintzen RQ; van Lier RA; von dem Borne AE; van Oers RH 《Blood》1996,87(5):1985-1989
Diagnosis of meningeal localization of lymphoid malignancies by means of cytologic examination of the cerebrospinal fluid (CSF) can be difficult. Thus far no reliable CSF tumor markers have been identified. CD27 is a transmembrane disulfide-linked 55-kD homodimer present on most peripheral blood T cells and on a subset of B cells. CD27 is also expressed on human malignant B cells and high levels of soluble CD27 can be present in the serum of patients with B-cell malignancies. The aim of this study is to determine prospectively the diagnostic value of CSF sCD27 as a tumor marker in patients with meningeal localization of lymphoid malignancies. CSF sCD27 levels were determined by sandwich enzyme-linked immunosorbent assay. The optimal cut-off value using receiver operator characteristics curves was found to be 10 U/mL. sCD27 levels were normal in all 50 control patients (lumbar disc protrusion) and in 39 of 40 samples obtained from patients with either solid tumors or acute myeloid leukemia. Of 104 CSF samples from 70 children with acute lymphoblastic leukemia (ALL) or non-Hodgkin's lymphoma (NHL) undergoing routine central nervous system (CNS) staging, sCD27 was false positive and false negative in only one sample each. In 70 samples from 45 patients suspected of meningeal localization of ALL or NHL, the sCD27 test had an excellent sensitivity (100%) and specificity (82%). In 7 patients with positive CSF studied longitudinally, sCD27 levels correlated very well with remission and relapse. sCD27 levels were not nonspecifically increased by the administration of cytostatic drugs. Finally, sCD27 was also elevated in the 4 patients studied with primary central nervous system lymphoma (PCNSL). CSF sCD27 is a promising tumor marker in patients with either meningeal localization of lymphoid malignancies or PCNSL, and can be useful in the differential diagnosis of CNS involvement by either lymphoid malignancies or solid tumors. 相似文献
54.
CJ Barry AIIP CRA AAIMBI RL Cooper FRACO FRACS RH Eikelboom BE PhD 《Clinical & experimental ophthalmology》1997,25(2):137-143
Purpose: To retrospectively examine the optic disc photographs of a glaucoma population for optic disc haemorrhages, vascular occlusions and vascular abnormalities. Methods: The optic disc photographs of 906 eyes of glaucoma and suspect glaucoma patients were examined. Optic disc photographs were taken annually, where possible, with the follow-up period varying between 1 and 14 years duration (mean, 2.89). Glaucoma patients are regularly reviewed every 4–6 months and glaucoma suspects every 1–2 years, depending on the ophthalmologist. Low-tension glaucoma patients were reviewed more frequently (mean, every 2.6 months). The results of the findings were compared to a control group of 39 subjects with a mean follow-up period of 7 years, using Fisher's exact test. Results: It was found that during the period under review, 7.4% (n= 67) of eyes had optic disc haemorrhages. The highest frequency of optic disc haemorrhages (37.5%) was found in the low tension glaucoma group (P= 0.0001) followed by 11.4% of primary open-angle glaucoma eyes (P= 0.03). In the normal group there were three eyes with optic disc haemorrhages and one with a disc collateral, which constitutes 5.1% vascular changes in this sub-group. Of the study eyes 2.8% had central retinal vein occlusions, 1.3% branch vein occlusion, 1.2% disc vessel abnormalities (loops) and 1.1% disc collaterals. Discrete nerve fibre layer haemorrhages and microaneurysms were found in 0.8% and 1.8% of eyes, respectively. Conclusions: A total of 16.8% of the eyes observed in this study had either disc haemorrhages or vascular changes. The underlying trend of vascular and haemorrhagic changes in glaucoma are demonstrated in this sample, which is in general agreement with previous studies. The high percentage of optic disc haemorrhages in low tension glaucoma is highlighted. The presence of microaneurysms and nerve fibre layer haemorrhages is interesting but of unknown significance. 相似文献
55.
56.
Powrie E 《Journal of advanced nursing》2003,42(4):413-423
BACKGROUND: During the last decade, primary care has been designated as the main provider of health care to people with learning disabilities. Practice nurses based in primary care teams are increasingly the first points of contact with health services. They make an important contribution to promoting good health, with health screening and illness prevention work being a significant part of their role. However, little is known about their views or involvement regarding the provision of primary care for people with learning disabilities. There is therefore a need to explore the nursing perspective, from within primary care, on the current provision of care for people with a learning disability. RESEARCH AIM: To inform the learning disability service of the role of primary care in current service provision for people with learning disabilities. RESEARCH METHOD: A survey of all practice nurses currently employed by Grampian Health Board in Aberdeen was conducted in June 2001. An initial pilot study was conducted in primary care and learning disability services. Data collection took place during June and July 2001. All practice nurses working in the geographical region of Grampian were invited to participate. RESULTS: Communication barriers exist, preventing access to health screening and treatment for some people with learning disabilities. Independent living skills, for example dietary management and budgeting, require additional community support. These conditions pose complex problems for practice nurses and other members of the primary care team. CONCLUSION: This study indicates a need for closer support and partnership with the learning disability service. The factors necessary for providing health care to people with learning disabilities extend beyond the domain of primary care teams. The findings of this survey have important implications for education and support to enable carers and professionals to provide a high standard of care. 相似文献
57.
Straub RH; Gluck T; Zeuner M; Scholmerich J; Lang B 《Rheumatology (Oxford, England)》1998,37(6):665-670
In chronic inflammatory diseases, cytokines stimulate the hypothalamus
pituitary adrenal axis and the hypothalamus autonomic nervous system (HANS)
axis. The present study was performed to find autonomic nervous function
parameters in patients with systemic lupus erythematosus (SLE) which are
suitable to demonstrate the activation of the HANS axis during systemic
inflammation. Thirty-four patients with SLE (age 35.3 +/- 1.9 yr) were
investigated by seven standardized autonomic nervous function tests. The
SLEDAI and laboratory parameters of systemic inflammation were assessed by
standard techniques. Pupillary latency time hyperreflexia was found in
29.4%, whereas maximal pupillary area was hyperresponsive in only 2.9%. A
total of 12% had overall cardiovascular autonomic nervous hyperreflexia.
Patients with latency time hyperreflexia had more severe systemic
inflammation [erythrocyte sedimentation rate (ESR): P < 0.001;
C-reactive protein (CRP): P = 0.0094; fibrinogen: P < 0.001; albumin: P
= 0.003; antinuclear antibodies: P = 0.020]. The longitudinal study of 13
patients during 4 yr demonstrated a parallel increase and decrease in
latency time percentile and ESR. SLE patients with increased systemic
inflammation had an activated HANS axis which can be measured by a
parasympathetic pupillary reflex test.
相似文献
58.
Elevation of serum cystathionine levels in patients with cobalamin and folate deficiency 总被引:14,自引:0,他引:14
Homocysteine can be methylated to form methionine by the cobalamin- (Cbl) and folate-dependent enzyme, methionine synthase; serum levels of total homocysteine are elevated in greater than 95% of patients with either Cbl or folate deficiency. Homocysteine can also condense with serine to form cystathionine in a pyridoxal phosphate-dependent reaction catalyzed by cystathionine beta-synthase. Cystathionine is subsequently cleaved to cysteine and alpha-ketobutyrate by the pyridoxal phosphate-dependent enzyme gamma-cystathionase. To assess levels of cystathionine in Cbl and folate deficiency, we developed a new capillary gas chromatographic-mass spectrometric assay and measured cystathionine in the serum of normal subjects and patients with clinically confirmed deficiencies of these vitamins. The normal range for serum cystathionine was 65 to 301 nmol/L (median = 126 nmol/L) for 50 normal blood donors. In 30 patients with clinically confirmed Cbl deficiency, values for cystathionine ranged from 208 nmol/L to 2,920 nmol/L (median = 816 nmol/L) and 26 (87%) had levels above the normal range. In 20 patients with clinically confirmed folate deficiency, cystathionine concentrations ranged from 138 nmol/L to 4,150 nmol/L (median = 1,560 nmol/L) and 19 (95%) had values above the normal range. Five homozygotes for cystathionine beta-synthase deficiency had high values for serum-total homocysteine and low or low-normal values for serum cystathionine that ranged from 30 nmol/L to 114 nmol/L even though they were on treatment with pyridoxine and had partially responded. One patient with a defect in the synthesis of 5-CH3- tetrahydrofolate and five patients with defects in the synthesis of CH3- Cbl had high values for serum-total homocysteine and high values for cystathionine that ranged from 311 nmol/L to 1,500 nmol/L even though they were on treatment with folic acid and Cbl, respectively, and had partially responded. We conclude that levels of cystathionine are evaluated in the serum of most patients with Cbl and folate deficiency and that they are useful in the differential diagnosis of an elevated serum-total homocysteine level. 相似文献
59.
Comparison between published clinical success of direct resin composite restorations in vital posterior teeth in 1995–2005 and 2006–2016 periods 下载免费PDF全文
Composites are increasing in popularity as restorative materials. This growing role indicates the necessity of studies on their clinical outcome. In this study, clinical studies published on the performance of posterior composite restorations were included except those of less than a 24‐month assessment period. Results of non‐vital, anterior or primary teeth and cervical single‐surface restorations were also excluded. Records about composite type, number of final recall restorations, failure/survival rate, assessment period and failure reasons were analysed for each decade. Overall survival/failure rates for studies in 1995–2005 were 89.41%/10.59% and for 2006–2016 were 86.87%/13.13%, respectively. In 1995–2005, the reasons for failure were secondary caries (29.47%) and composite fracture (28.84%) with low tooth fracture (3.45%) compared with reasons of failure in 2006–2016, which were secondary caries (25.68%), composite fracture (39.07%), and tooth fracture (23.76%). An increase in incidence of composite fracture, tooth fracture and need for endodontic treatment as failure reasons was noted in the latter decade in addition to a decrease in secondary caries, postoperative sensitivity, unsatisfactory marginal adaptation and wear. The overall rates of failure showed little difference, but the causes showed a notable change. This is believed to be a reflection of increased use of composites for larger restorations and possibly changes of material characteristics. 相似文献
60.
Treatment of progressive Hodgkin's disease with intensive chemoradiotherapy and autologous bone marrow transplantation 总被引:2,自引:0,他引:2
Phillips GL; Wolff SN; Herzig RH; Lazarus HM; Fay JW; Lin HS; Shina DC; Glasgow GP; Griffith RC; Lamb CW 《Blood》1989,73(8):2086-2092
Twenty-six patients with progressive Hodgkin's disease after conventional chemotherapy received intensive chemoradiotherapy and autologous bone marrow transplantation (ABMT); 19 also received additional involved-field radiotherapy. Twenty-one patients [81%, 95% confidence intervals (CI) 61% to 94%] attained complete (n = 18) or partial responses. Ten patients (38%, 95% CI 20% to 59%) are disease- free a median of 4.5 years later (range 3.5 to 7.0 years), including seven patients with continuous complete responses. The likelihood of overall response was not significantly influenced by any clinical or treatment variable examined. However, there was a trend favoring patients with higher Karnofsky scores, and higher scores were associated with attainment of complete responses (P = .06 and P = .02, respectively, Mann-Whitney U test). Both higher Karnofsky scores and shorter durations of disease before transplantation were associated with improved survival in a stepwise Cox multivariate analysis. The chief cause of failure was progression at sites previously involved with Hodgkin's disease. No patient relapsed in the marrow, and two of three patients with a history of marrow involvement with Hodgkin's disease achieved durable complete responses after transplantation. These data suggest that inadequate pretransplant conditioning, and not the reinoculation of occult tumor cells in the autologous marrow, caused most relapses. Fatal treatment-related toxicity occurred in six patients. Three patients died of idiopathic interstitial pneumonitis; each had previously received local mediastinal irradiation before intensive chemoradiotherapy. Intensive chemoradiotherapy and ABMT produces durable responses in some patients with Hodgkin's disease incurable with conventional therapy. Use of such therapies at the first sign of failure with conventional chemotherapy and development of more effective conditioning regimens should further improve results. 相似文献