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41.
Decreased immune functions have been suggested as a cause for the increased incidence of autoimmunity, malignancy, and infection in the elderly population. To assess the possible role of changes in macrophage function in the aging process we studied the Fc receptor- mediated clearance of IgG-coated erythrocytes in 56 healthy normal volunteers by following the removal of radiolabeled autologous erythrocytes. An age-related decrease in Fc-mediated clearance rates in both female and male subjects was found, which suggests a physiological decline of this macrophage function in older individuals. 相似文献
42.
Insulin-like growth factor-1 potentiates expansion of interleukin-7- dependent pro-B cells 总被引:4,自引:0,他引:4
Commitment to B-lymphocyte differentiation is characterized by expression of the B220 form of the common leukocyte antigen (Ly-5) and D-JH rearrangement of the Ig heavy chain gene complex. B-lineage progenitor cells, or pro-B cells, that have initiated Ig gene rearrangement, but do not express detectable Ig heavy or light chain protein, have recently been shown to retain substantial capacity for expansion in vitro in the presence of bone marrow (BM) stromal cells and interleukin-7 (IL-7). Although the potentiating effect of stromal cells on pro-B-cell proliferation can be partially attributed to the ligand for the proto-oncogene receptor c-kit (c-kit ligand [KL] or stem cell factor), several lines of evidence suggest that c-kit-mediated cell signalling is not required for pro-B-cell expansion. Previous studies from this laboratory demonstrated that insulin-like growth factor-1 (IGF-1) potentiated the proliferative effect of IL-7 on nonadherent cells from lymphoid long-term BM cultures in a manner similar to that shown for KL. To further delineate specific cell stages that respond to lymphopoietic cytokines, we derived continuously proliferating pro-B-cell lines from day-14 murine fetal liver in the presence of IL-7 and BM stromal cell clone S10. Initial expansion and continued proliferation of these pro-B-cell lines was absolutely dependent on the presence of both IL-7 and stromal cells. In the absence of KL, IL-7-stimulated proliferation of these cells in short- term cultures and addition of either recombinant IGF-1 or KL significantly potentiated this proliferative response. Although IGF-2 and insulin also potentiated the effect of IL-7, our data suggest that neither IGF-2 nor insulin represent normal regulators of intramyeloid lymphocyte development. IGF-1 and KL activate unique cascades of intracellular signalling events and inclusion of both cytokines in cultures of IL-7-stimulated pro-B cells resulted in additive potentiation of the proliferative response. Taken together, these results suggest that expansion of pro-B cells in vivo is maintained by at least three stromal cell-derived cytokines. IL-7 appears to be unique in delivering the primary proliferative signal for pro-B-cell expansion; however, both KL and IGF-1 potentiate the proliferative effect of IL-7 on these cells. The functional redundancy and additive effects of IGF-1 and KL as amplification signals for developing B- lineage cells underscore the essential nature of clonal expansion and diversification in development of immunocompetent lymphoid cells. 相似文献
43.
Reduced tocopherol content of B cells from patients with chronic lymphocytic leukemia 总被引:1,自引:0,他引:1
The tocopherol content of lymphocytes, erythrocytes, and plasma from patients with chronic lymphocytic leukemia (CLL), hairy cell leukemia (HCL), and normal subjects was measured by a sensitive high performance liquid chromatographic method. Lymphocytes from patients with CLL had lower values of tocopherol (1.7 +/- 1.0 micrograms/10(9) cells) than lymphocytes from normal subjects (3.8 +/- 0.7 micrograms/10(9) cells). Mononuclear cells from patients with HCL had an increased tocopherol content of 6.2 +/- 1.0 micrograms/10(9) cells. Subfractionation of the lymphocytes from patients with CLL into T- and B-cell subgroups showed that the tocopherol content of T cells was the same as in normal subjects (4.1 +/- 0.5 micrograms/10(9) cells versus 3.5 +/- 1.2), but that the tocopherol content of the B cells was markedly reduced compared to normals (2.6 +/- 1.0 versus 6.0 +/- 1.3). 相似文献
44.
Verdonck LF; Dekker AW; de Gast GC; van Kempen ML; Lokhorst HM; Nieuwenhuis HK 《Blood》1994,83(10):3090-3096
Despite prophylaxis with immunosuppressive drugs, severe acute graft- versus-host disease (GVHD) remains a major cause of morbidity and mortality in patients transplanted with unmodified bone marrow (BM) grafts from HLA-identical siblings. Although T-cell depletion of the BM graft has evolved as the most effective method to prevent severe acute GVHD, this beneficial effect is counterbalanced by an increased rate of graft failure and relapse of the disease. To find an approach to T-cell depletion that may avoid these extreme risks, we gave BM recipients a fixed low number of 1 x 10(5) donor T cells per kilogram of recipient's body weight in the graft. This corresponds with 99% T-cell depletion and is achieved by the addition of T cells to the graft that was previously depleted of T cells. A total of 70 patients with hematologic malignancies or aplastic anemia, including 40 patients with standard- risk leukemias, received BM grafts, depleted of T cells according to this approach, from HLA-identical siblings. The preparative regimen consisted of cyclophosphamide and total body irradiation. The patients also received a short course of cyclosporine posttransplant. Graft failure did not occur. Acute GVHD, only grade I or II, was seen in 70% of the patients and was limited to the skin in all patients. Chronic GVHD occurred in 31% of the patients and, with the exception of 1 patient, was limited to the skin as well. Relapse occurred in 3 of 40 (8%) patients with standard-risk leukemias, resulting in a projected survival at 5 years of 80%. Patients with standard-risk diseases had a procedure-related mortality of 11%. Quality of life, determined 1 year after BM transplant, was good in almost all patients with standard-risk diseases. Thus, this approach of T-cell depletion may be an approach that avoids the development of severe acute and chronic GVHD without damaging the function or antileukemic effect of the graft and that has a low transplant-related morbidity and mortality. 相似文献
45.
LF Yap D Lee ANM Khairuddin MF Pairan B Puspita CH Siar IC Paterson 《Oral diseases》2015,21(7):850-857
NOTCH signalling can exert oncogenic or tumour suppressive effects in both solid and haematological malignancies. Similar to T‐cell acute lymphoblastic leukaemia (T‐ALL), early studies suggested a pro‐tumorigenic role of NOTCH in head and neck squamous cell carcinoma (HNSCC), mainly based on the increased expression levels of the genes within the pathway. Recently, data from exome sequencing analyses unexpectedly pointed to a tumour suppressor role for NOTCH in HNSCC by identifying loss‐of‐function mutations in the NOTCH1 gene in a significant proportion of patients. These data have questioned the accepted role of NOTCH in HNSCC and the possible rationale of targeting NOTCH in this disease. This review summarises the current information on NOTCH signalling in HNSCC and discusses how this pathway can apparently exert opposing effects within the same disease. 相似文献
46.
Camila Vieira Ligo Teixeira Thiago JR Rezende Marina Weiler Mateus H Nogueira Brunno M Campos Luiz FL Pegoraro Jessica E Vicentini Gabriela Scriptore Fernando Cendes Marcio LF Balthazar 《Age (Dordrecht, Netherlands)》2016,38(3):51
Mild cognitive impairment (aMCI) is a clinical condition, with high risk to develop Alzheimer’s disease. Physical exercise may have positive effect on cognition and brain structure in older adults. However, it is still under research whether these influences are true on aMCI subjects with low Ab_42 and high total tau in cerebrospinal fluid (CSF), which is considered a biomarker for AD. Therefore, we aimed to investigate a possible relation between aerobic fitness (AF) and gray matter (GM) volume and AF and white matter (WM) integrity in aMCI with a CSF biomarker. Twenty-two participants with aMCI acquired the images on a 3.0-T MRI. AF was assessed by a graded exercise test on a treadmill. Voxel-based morphometry and tract-based spatial statistic methods were used to analyze the GM volume and WM microstructural integrity, respectively. We correlated AF and GM volume and WM integrity in aMCI (p < 0.05, FWE corrected, cluster with at least five voxels). There was a positive relation between AF and GM volume mostly in frontal superior cortex. In WM integrity, AF was positively correlated with fractional anisotropy and negatively correlated with mean diffusivity and radial diffusivity, all in the same tracts that interconnect frontal, temporal, parietal, and occipital areas (longitudinal fasciculus, fronto-occipital fasciculus, and corpus callosum). These results suggest that aerobic fitness may have a positive influence on protection of brain even in aMCI CSF biomarker, a high-risk population to convert to AD. 相似文献
47.
Background
Imprisonment may lead to the development of mental illness, especially depression. This study examines the clinical and sociodemographic profiles of imprisoned women, identifies indicative signs of depression, and relates these indicators to other variables. 相似文献48.
White B Jeansonne LO Cook M Chavarriaga LF Goldenberg EA Davis SS Smith CD Khaitan L Lin E 《Obesity surgery》2009,19(6):783-787
Background Obese patients with gastroesophageal reflux disease (GERD) refractory to medical therapy are a challenging patient population
as obesity is a preoperative predictor of failure after antireflux surgery. We therefore sought to evaluate outcomes using
one of two commercially available endoluminal therapies in this population.
Methods Consecutive obese patients (body mass index (BMI) > 30) with GERD (DeMeester >14.5) undergoing either Plicator (NDO) or Stretta
(Curon) were identified in our single-institution prospective database. Outcomes assessed were: (1) failure rate (absolutely
no symptomatic improvement after procedure and/or need for subsequent antireflux surgery), (2) postoperative vs. preoperative
symptom (heartburn, chest pain, regurgitation, dysphagia, cough, hoarseness, and asthma) scores, and (3) proton-pump inhibitor
(PPI) medication use.
Results Twenty-two patients each underwent an endoluminal therapy (ten Plicator patients and 12 Stretta patients) with mean follow-up
of 1.5 years. There were no treatment-associated complications. Mean BMI was not different between Plicator and Stretta groups
(39.6 vs. 38.6, respectively, p = 0.33). The failure rate for the entire cohort was 28% (10% Plicator vs. 42% Stretta, p = 0.11). The proportion of patients reporting moderate/severe symptoms postop was significantly less than preop: chest pain
9% vs. 13% (p = 0.04), cough 22% vs. 36% preop (p = 0.025), voice changes 9% vs. 36% preop (p = 0.012), and dysphagia 9% vs. 32% preop (p = 0.04). The proportion of patients on PPI medications postop was also less than preop (45% vs. 81%, p = 0.1)
Conclusion Endoluminal treatment can provide a safe means of improving GERD symptoms for some obese patients, though many will continue
to require medication therapy also. Further work aimed at understanding optimal candidates for endoluminal therapy in this
patient population is warranted. 相似文献
49.
Cystatin C and carotid intima-media thickness in asymptomatic adults: the Multi-Ethnic Study of Atherosclerosis (MESA) 总被引:1,自引:0,他引:1
AL Bui R Katz B Kestenbaum IH de Boer LF Fried JF Polak BA Wasserman MJ Sarnak D Siscovick MG Shlipak 《American journal of kidney diseases》2009,53(3):389-398
BACKGROUND: Persons with early kidney disease have an increased risk of cardiovascular events and mortality, but the importance of accelerated atherosclerosis in promoting these outcomes is unclear. We therefore explored whether serum cystatin C level is associated with carotid intima-media thickness (IMT) in ambulatory adults without clinical heart disease. STUDY DESIGN: Cross-sectional study. SETTING & PARTICIPANTS: We evaluated 6,557 ethnically diverse persons free of clinical cardiovascular disease aged 45 to 84 years at the baseline visit of the Multi-Ethnic Study of Atherosclerosis. PREDICTORS: Kidney function was estimated by using 2 methods: serum cystatin C level and estimated glomerular filtration rate, based on creatinine and cystatin C levels. OUTCOMES & MEASUREMENTS: Study outcomes were internal and common carotid IMT, measured by using high-resolution B-mode ultrasound. Multivariate linear and logistic regressions were used to evaluate the independent association of kidney function with carotid IMT. RESULTS: In unadjusted linear analysis, each SD (0.23 mg/L) greater cystatin C level was associated with 0.091-mm greater internal carotid IMT (P < 0.001), but this association was diminished by 70% after adjustment for age, sex, and race/ethnicity (0.027 mm; P < 0.001) and was no longer significant after adjustment for cardiovascular risk factors (0.005 mm; P = 0.5). Similarly, the strong unadjusted associations of cystatin C level with common carotid IMT disappeared after adjustment. Chronic kidney disease, defined by using either creatinine level or cystatin C-based estimated glomerular filtration rate less than 60 mL/min/1.73 m(2), had no independent association with internal and common carotid IMT. LIMITATIONS: There were few participants with severe kidney disease. CONCLUSIONS: Cystatin C level had no independent association with carotid IMT in a population free of clinical heart disease. This observation suggests that accelerated atherosclerosis is unlikely to be the primary mechanism explaining the independent association of cystatin C level with cardiovascular risk. 相似文献
50.