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21.
bcl-2 transgene expression promotes survival and reduces proliferation of CD3-CD4-CD8- T cell progenitors 总被引:16,自引:0,他引:16
Proliferative expansion and apoptotic cell death play prominent roles in T
cell development. The molecular control of cell cycle progression and
apoptosis appear to be inter-connected since the Bcl-2 protein can inhibit
apoptosis and slow cell cycle progression in cortical thymocytes and mature
T cells, particularly during the transition from the quiescent state into
the cell cycle. Here the impact of bcl-2 transgene expression on
CD3-CD4-CD8- T cell progenitors was assessed. Bcl-2 enhanced the survival
of these progenitors at all of the four major differentiation stages, CD25-
CD44+ (pro-T1), CD25 + CD44+ (pro- T2), CD25 + CD44- (pro-T3) and
CD25-CD44- (pro-T4). However, it reduced cell cycling and slowed turnover
only in the pro-T4 subset. From an analysis of bcl-2 transgenic mice
expressing a TCR transgene or bearing a mutation in the scid or rag-1 gene
we conclude that Bcl-2 inhibits proliferation only of T cell progenitors
that are activated via the pre- TCR, not those stimulated via c-Kit and the
IL-7 receptor.
相似文献
22.
AW El‐Hattab J Bournat PA Eng JBS Wu BA Walker P Stankiewicz SW Cheung CW Brown 《Clinical genetics》2011,79(6):531-538
El‐Hattab AW, Bournat J, Eng PA, Wu JBS, Walker BA, Stankiewicz P, Cheung SW, Brown CW. Microduplication of Xp11.23p11.3 with effects on cognition, behavior, and craniofacial development. We report an ~1.3 Mb tandem duplication at Xp11.23p11.3 in an 11‐year‐old boy with pleasant personality, hyperactivity, learning and visual‐spatial difficulties, relative microcephaly, long face, stellate iris pattern, and periorbital fullness. This clinical presentation is milder and distinct from that of patients with partially overlapping Xp11.22p11.23 duplications which have been described in males and females with intellectual disability, language delay, autistic behaviors, and seizures. The duplicated region harbors three known X‐linked mental retardation genes: FTSJ1, ZNF81, and SYN1. Quantitative polymerase chain reaction from whole blood total RNA showed increased expression of three genes located in the duplicated region: EBP, WDR13, and ZNF81. Thus, over‐expression of genes in the interval may contribute to the observed phenotype. Many of the features seen in this patient are present in individuals with Williams‐Beuren syndrome (WBS). Interestingly, the SYN1 gene within the duplicated interval, as well as the STX1A gene, within the WBS critical region, co‐localize to presynaptic active zones, and play important roles in neurotransmitter release. 相似文献
23.
J W Coebergh A van der Does-van den Berg W A Kamps J A Rammeloo H A Valkenburg E R van Wering 《Medical and pediatric oncology》1991,19(3):169-174
A retrospective study was done of the incidence of non-Hodgkin's lymphoma (NHL) in children in the Netherlands in the period 1973-85 in relation to that of acute lymphoblastic leukemia (ALL). Complete ascertainment of cases was most likely achieved through the network of cooperating pediatricians of the Dutch Childhood Leukemia Study Group (DCLSG). The incidence of NHL remained constant at 0.75 per 10(5) children per year; the boy/girl ratio was 2.5. In +/- 25% of cases the disease was localized at diagnosis. Of children with NHL who were not listed in the DCLSG leukemia register, 19% had greater than or equal to 25% lymphoblasts in the bone marrow at diagnosis, representing an overlap with ALL of +/- 5%. In 1% of the children with NHL an immuno-deficiency disorder preceded the diagnosis. The incidence of Hodgkin's disease (HD) was 0.3 per 10(5) children per year, with some fluctuation over time, the peak being 0.7 in 1983. The boy/girl ratio was 2.7. Age-specific incidence rates, clinical features of NHL and HD, as well as the ALL to NHL ratio corresponded with those in other European countries and for white children in the USA. 相似文献
24.
25.
Ohne Zusammenfassung
RID="*"
ID="*"Erweiterte Fassung eines Vortrags anl?sslich des 20j?hrigen Bestehens der Fachkliniken Hohenurach in Bad Urach.
Prof. Dr. iur. Hans Kamps und Dr. iur. Regine Kiesecker, Bezirks?rztekammer Südwürttemberg, Haldenhaustra?e 11, D-72770 Reutlingen 相似文献
26.
目的 研究分析既往疾病史和胆道癌 (包括胆囊癌、肝外胆管癌和壶腹部癌 )的关系。方法 自 1997年 6月~ 2 0 0 1年 5月 ,在上海市区开展了一项大规模的基于全人群的胆道癌的病例对照研究 ,共收集、调查了 6 6 4例胆道癌新病例和 894例人群对照。结果 研究发现既往有胆囊炎疾病史者患胆囊癌、肝外胆管癌的危险性升高 ,调整的比数比分别为 2 .2 (95 %CI =1.3~ 3.6 )和 1.9(95 %CI=1.0~ 3.3)。糖尿病患者患胆囊癌的危险性增加 ,调整的比数比为 1.5 (95 %CI=0 .9~ 2 .5 ) ,在非胆结石者中调整的比数比为 2 .0 (95 %CI=0 .9~ 4 .5 ) ;此外 ,研究还发现肝硬化者患肝外胆管癌的危险性明显增加 ,调整的比数比为 3.0 (95 %CI=1.0~ 9.1) ,在非胆结石者中调整的比数比为 4 .9(95 %CI=1.2~ 19.8)。结论 该项研究为论证胆囊炎症增加患胆道癌的危险性提供了依据 ,研究还提示糖尿病和肝硬化分别提高患胆囊癌和肝外胆管癌的危险性。 相似文献
27.
28.
SE Daley AD Pearson AW Craft J Kernahan RA Wyllie L Price C Brock C Hetherington D Halliday K Bartlett 《Archives of disease in childhood》1996,75(4):273-281
Whole body protein synthesis and catabolism were measured using the [ring-2H5]phenylalanine and [1-13C]leucine primed constant infusion technique in 32 paediatric patients with cancer at different stages of treatment. Rates of synthesis (S) and catabolism (C) derived from the [ring-2H5]phenylalanine and [1-13C]leucine models were 4.7 (SD 1.3) (S) and 6.0 (1.5) (C) g/d/kg, and 5.5 (0.8) (S) and 6.8 (1.2) (C) g/d/kg, respectively. These results show that these two tracer techniques give similar results in this study population. Comparison of these values with results previously reported for groups of control children using the [ring-2H5]phenylalanine model (S = 3.69 and 3.93; C = 4.09 and 4.28 g/d/kg) and the [1-13C]leucine model (S = 4.32; C = 4.85 g/d/kg) show that rates of synthesis and catabolism were higher in cancer patients than in controls. Thus whole body protein turnover is increased in children under treatment for cancer. Other indices of metabolism such as plasma amino acids and intermediary metabolites were also measured and showed that, although subjects were in isotopic steady state, there were significant metabolic changes during the course of the primed constant infusions used to measure protein turnover. 相似文献
29.
M Cole L Parker AW Craft S Bell G Dale AC McGill JA Seviour J Smith 《Archives of disease in childhood》1993,68(3):376-378
The relationship between homovanillic acid (HVA), vanillylmandelic acid (VMA), and creatinine in the urine of 6 month old babies has been studied and reference ranges in the form of centiles constructed for HVA and VMA against creatinine. Over 10,000 urine samples were collected from babies in four health districts in the north of England. HVA and VMA concentration, either independently or when divided by creatinine concentration, were dependent upon the absolute concentration of creatinine in the sample. After adjustment for creatinine significant differences in the mean concentration of HVA were found between sexes. No such differences were found for VMA. HVA and VMA were also found to be age dependent. Centiles were constructed using a procedure which makes no distributional assumptions about the data. The net effect of utilising these centiles was to increase the predictive value of a positive screening test from 20% to 40% without any increase in the false negative rate. 相似文献
30.
Elise A. L. Hugenholtz Do A. Piers Willem A. Kamps Ian J. Cohen Chedva Lerman Ernesto Lubin Rina Zaizov 《Pediatric blood & cancer》1994,22(4):236-239
In order to detect skeletal metastases in patients with Ewing's sarcoma, bone scanning is commonly used. However, little information is available about the scintigraphic aspects of the primary Ewing's sarcoma during non-surgical treatment and follow-up. We studied retrospectively the significance of bone scintigraphic findings at the primary tumor site of 58 patients with a Ewing's sarcoma. These patients had chemotherapy and radiotherapy. At presentation 53/58 patients showed an increased tracer uptake at the primary tumor site while 5 patients with a pelvic or sacral bone localization had a normal scan. Bone scans made during treatment and more than 2 years thereafter in the 32 eligible patients demonstrated three patterns. In 16 patients the hot spot disappeared and no local tumor recurrence was encountered. In the other 16 patients the high uptake at the primary tumor site either persisted or diminished first to a normal uptake after a median period of 18 months (range 12-36 months) and returned again to a high uptake within 6-12 months. In these patients local Ewing's sarcoma was still present in 13, while in the other 3 cases a benign disorder (fracture, ectopic bone formation) was the underlying cause. These findings suggest that in non-surgically treated Ewing's sarcoma persisting increased tracer uptake or its recurrence is highly suspicious for the presence of Ewing's sarcoma, while bone scans becoming negative and remaining so for more than 12 months suggest the absence of local tumor. © 1994 Wiley-Liss, Inc. 相似文献