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41.
R. S. Verma R. A. Conte M. J. Macera A. S. S. I. Khan S. Hebi A. A. Masoud A. Al Zaman M. Al Bader 《American journal of medical genetics. Part A》1993,46(1):104-108
A newborn infant was referred because of low-set ears, mild downward slant of the palpebral fissues, micrognathia with higharched palate, a flat midface, small mouth, and thin upper lip with cupid bow configuration. To some extent her cry resembled that associated with cri du chat syndrome. Cytogenetic findings with G- and Q-banding alone failed to characterize precisely the complex translocations. By the chromosome in situ suppression (CISS) hybridization technique using whole chromosome specific probes, a complex 4 breakpoint rearrangement involving both arms of a single chromosome 1 with the long arms of chromosome 5 and 11 was disclosed, i.e., 46,XX, der(1),t(1;5) t(1;11) (5qter→5q31::1p31.3→1q44::11q23→11qter;5pter→5q31::1p31.3→1pter;11pter→11q23::1q44→1qter). Gene deregulation and position effect may explain the multiple anomalies in individuals with apparently balanced translocations may shed some light towards unveiling the clinical consequences associated with aberrations which are presumably balanced. © 1993 Wiley-Liss, Inc. 相似文献
42.
The rel-associated pp40 protein prevents DNA binding of Rel and NF-kappa B: relationship with I kappa B beta and regulation by phosphorylation 总被引:71,自引:0,他引:71
L D Kerr J Inoue N Davis E Link P A Baeuerle H R Bose I M Verma 《Genes & development》1991,5(8):1464-1476
The product of proto-oncogene Rel associates with a number of cellular proteins. We have studied the effect of one of them, a phosphoprotein of 40 kD (pp40), on the DNA-binding activity of the Rel protein. We demonstrate that purified pp40 not only inhibits the binding of Rel, but also NF-kappa B (p50-p65) heterocomplex to DNA. Additionally, I kappa B beta, but not I kappa B alpha, also prevented the binding of Rel to the kappa B site. I kappa B beta and pp40 are related proteins because (1) they share a number of common tryptic peptides, (2) their inhibitory effect on DNA binding can be abolished by preincubation with pp40-specific antiserum, and (3) labeled I kappa B beta can be immunoprecipitated with pp40 antibodies. pp40 is part of the Rel complex present in the cytoplasm and nuclear extracts of WEHI-231 cells. The activity of pp40 to inhibit the DNA binding of Rel and NF-kappa B is modulated by phosphorylation. 相似文献
43.
Primary primitive neuroectodermal tumor of the cauda equina 总被引:5,自引:0,他引:5
Primitive neuroectodermal tumors (PNETs) are aggressive neoplasms composed predominantly of undifferentiated cells that show evidence of neural differentiation. Although their classification has been controversial, PNETs are well recognized primary tumors of both central and peripheral nervous systems. PNETs must be distinguished from other round-cell tumors, including Ewing's sarcoma, lymphoma, rhabdomyosarcoma, and small cell carcinoma. Intraspinal PNETs are rare neoplasms that are usually metastatic in origin. We describe the eighth reported primary PNET of the cauda equina that developed in a 52-year-old man with no significant medical history. The tumor was characterized by Homer-Wright rosettes and immunoreactivity for CD99, glial fibrillary acidic protein, neuron-specific enolase S100, and synaptophysin. The anatomic location of primary intrathecal PNETs is important as those arising in the spinal cord develop in the central nervous system, whereas those arising in the cauda equina develop in the peripheral nervous system. The histogenesis of intrathecal PNETs may be multifactorial. 相似文献
44.
45.
Szabo Gyongyi Mandrekar Pranoti Verma Bikash Isaac Ann Catalano Donna 《Journal of clinical immunology》1994,14(6):340-352
The hypothesis that acute ethanol uptake plus trauma can synergize to increase immunosuppression was tested. We found that, unlike non-alcohol-exposed patients, patients with acute alcohol use prior to trauma have a transient decrease in monocyte tumor necrosis factor (TNF) production during the very early postinjury (0–3 days) period. However, TNF production by these alcoholexposed patients' monocytes (MØ) became hyperelevated late postinjury (>9 days). Consequently, these massively elevated MØ TNF levels can contribute to posttrauma immunosuppression after acute alcohol use. We also demonstrate that normal monocyte activation with the superantigen,Staphylococcus enterotoxin B (SEB), results in a preferential induction of cellassociated MØ TNF production, described as characteristic of immunosuppressed trauma patients. Acutein vitro ethanol treatment down-regulated the elevated TNF production by trauma patients' MØ after either SEB, muramyl-dipeptide (MDP), interferon- plus MDP, or lipopolysaccharide (LPS) stimulation. Both SEB- and LPS-induced TNF mRNA induction was inhibited by acute alcohol treatment in normal MØ, indicating that ethanol can regulate cytokine gene expression. An additional immunosuppressive effect of acute ethanol's stimulation was suggested by its induction of elevated transforming growth factor production in trauma patients' activated MØ. 相似文献
46.
Eight patients with sickle cell anemia (SS hemoglobin) were found to have decreased plasma levels of prekallikrein compared to normal control subjects or patients with other types of anemia. The prekallikrein levels in the patients with sickle cell anemia were found to decrease further during a sickle cell crisis. These results suggest that components of the kallikrein-kinin system are profoundly affected in patients with sickle cell anemia, and during crises may play a role in the clinical presentation of patients. 相似文献
47.
Macrocarposide, a new isoflavanone c-glucoside from Pterocarpus macrocarpus heart wood 总被引:1,自引:0,他引:1
Macrocarposide has been isolated for the first time as a natural product from the heartwood of PTEROCARPUS MACROCARPUS along with some known compounds. Based on its spectral and chemical evidence, it has been assigned the structure dalbergioidin-6- C-glucoside ( 1). 相似文献
48.
Modulation of mouse skin tumor promotion by dietary 13-cis-retinoic acid and {alpha}-difluoromethylornithine 总被引:1,自引:1,他引:0
The effects of dietary supplementation of 13-cis-retinoic acid(13-cis-RA) and -difluoromethylornithine (DFMO) in the drinkingwater on 12-O-tetradecanoylphorbol-13-acetate (TPA)-promotedskin tumor formation was determined. Administration of 13-cis-RAin the diet and DFMO in the drinking water was started 1 weekand 2 days before the first TPA application to the dimethylbenz[a]anthracene-initiatedskin of either female CD-I or SENCAR mice, respectively. Dietary13-cis-RA failed to inhibit both the tumor yield and the incidence;papillomas per mouse at 0, 5, 50, 100 and 200 mg/kg diet 13-cis-RAdoses were 25, 30, 22, 28 and 25 respectively at 18 weeks ofpromotion treatment and at all doses 100% of the mice bore papillomas.However, dietary 13-cis-RA dramatically reduced the size ofskin tumor promoted with TPA. 13-cis-RA at doses of 5, 50, 100and 200 mg/kg diet inhibited skin papillomas (> 4 mm diameter)per mouse by 28, 55, 76 and 93%, respectively. Retinoid treatmentdid not affect body weight gains and the survival was more than80% in all groups. In accord with our previous findings, DFMOwhen given in drinking water, was a very effective inhibitorof mouse skin tumor promotion by TPA; DFMO at 0.25% concentrationinhibited the number of papillomas by 50%. Inhibition of skintumor promotion by combined treatments with dietary 13-cis-RA(100 mg/kg) and DFMO (0.25%) in the drinking water was possiblyadditive. The retinoid and DFMO preclude TPA-increased ornithinedecarboxylase (ODC) activity and the accumulation of putrescineby differential effects on ODC, an enzyme associated with skintumor promotion by TPA. 相似文献
49.
Pulmonary tuberculosis among contacts of patients with tuberculosis in an urban Indian population. 总被引:1,自引:0,他引:1
R A Kumar M Saran B L Verma R N Srivastava 《Journal of epidemiology and community health》1984,38(3):253-258
The study was conducted among 1810 contacts of 50 index "cases"/"suspects" of pulmonary tuberculosis including 312 household and 1498 neighbourhood contacts in the Jhansi city of Uttar Pradesh. The overall prevalence of radiologically active and bacteriologically confirmed tuberculosis was 2.9% and 1.1%. The prevalence rates of radiologically active and bacteriologically confirmed disease, although comparatively high in both the contact groups, were significantly higher in household (5.4% and 2.6%) than in neighbourhood contacts (2.3% and 0.8%). Significant differences in distribution of secondary cases among clusters were observed. Although higher prevalence rates were found in contacts of sputum positive source than in contacts of sputum negative source in both the contact groups, the statistical difference was observed to be insignificant. Case yield among contact symptomatics was 80.0% (30.8% cases and 49.2% suspects). 相似文献
50.
Seventeen children presenting with leucocoria were subjected to complete investigations. Careful A and B mode ultrasonography allowed us to make the correct diagnosis of retinoblastoma in 11 eyes of 9 patients, which was confirmed by histopathology or by response to radiotherapy. The diagnosis of retinoblastoma was not missed ultrasonographically in any of the eyes studied. The "V/W" configuration and absence of vascular pulsations on A mode; the "mixed" pattern and absence of choroidal excavation and orbital shadowing on B mode were found to be essential echographic features in characterizing the tumor and in differentiating it from other conditions including vitreous hemorrhage. The ultrasonographic features of early extraocular extension of retinoblastoma are discussed. Careful ultrasonic evaluation of leucocoria would seem to be invaluable in obviating the possibility of misdiagnosis in such problematic cases. 相似文献