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21.
Igarashi S; Takiyama Y; Cancel G; Rogaeva EA; Sasaki H; Wakisaka A; Zhou YX; Takano H; Endo K; Sanpei K; Oyake M; Tanaka H; Stevanin G; Abbas N; Durr A; Rogaev EI; Sherrington R; Tsuda T; Ikeda M; Cassa E; Nishizawa M; Benomar A; Julien J; Weissenbach J; Tsuji S 《Human molecular genetics》1996,5(7):923-932
Machado-Joseph disease (MJD) is an autosomal dominant neurodegenerative
disorder caused by unstable expansion of a CAG repeat in the MJD1 gene at
14q32.1. To identify elements affecting the intergenerational instability
of the CAG repeat, we investigated whether the CGG/GGG polymorphism at the
3' end of the CAG repeat affects intergenerational instability of the CAG
repeat. The [expanded (CAG)n-CGG]/[normal (CAG)n- GGG] haplotypes were
found to result in significantly greater instability of the CAG repeat
compared to the [expanded (CAG)n- CGG]/[normal (CAG)n-CGG] or [expanded
(CAG)nGGG]/[normal (CAG)n-GGG] haplotypes. Multiple stepwise logistic
regression analysis revealed that the relative risk for a large
intergenerational change in the number of CAG repeat units (< -2 or >
2) is 7.7-fold (95% CI: 2.5-23.9) higher in the case of paternal
transmission than in that of maternal transmission and 7.4-fold (95% CI:
2.4-23.3) higher in the case of transmission from a parent with the
[expanded (CAG)n-CGG]/[normal (CAG)n-GGG] haplotypes than in that of
transmission from a parent with the [expanded (CAG)n-CGG]/[normal
(CAG)n-CGG] or [expanded (CAG)n- GGG]/[normal (CAG)n-GGG] haplotypes. The
combination of paternal transmission and the [expanded (CAG)n-CGG]/[normal
(CAG)n-GGG] haplotypes resulted in a 75.2-fold (95% CI: 9.0-625.0) increase
in the relative risk compared with that of maternal transmission and the
[expanded (CAG)n-CGG]/[normal (CAG)n-CGG] or [expanded (CAG)n- GGG]/[normal
(CAG)n-GGG] haplotypes. The results suggest that an inter- allelic
interaction is involved in the intergenerational instability of the
expanded CAG repeat.
相似文献
22.
Abbas Haghparast Jamal Shams Ali Khatibi Amir-Mohammad Alizadeh Mohammad Kamalinejad 《Neuroscience letters》2008
The problem of morphine tolerance and dependence is a universal phenomenon threatening social health everywhere the world. The major objective of this paper was to investigate the effects of fruit essential oil (FEO) of Cuminum cyminum on acquisition and expression of morphine tolerance and dependence in mice. Animals were rendered dependent on morphine using the well-established method in which was morphine (50, 50, 75 mg/kg; s.c.) injected three times daily for 3 days. In experimental groups, administration of FEO (0.001, 0.01, 0.1, 0.5, 1 and 2%; 5 ml/kg; i.p.) or Tween-80 (5 ml/kg; i.p.) was performed 60 min prior to each morphine injection (for acquisition) or the last injection of morphine on test day (for expression). Morphine tolerance was measured by tail-flick before and after administration of a single dose of morphine (50 mg/kg; s.c.) in test day (4th day). Morphine dependence was also evaluated by counting the number of jumps after injection of naloxone (5 mg/kg; i.p.) on the test day. The results showed that Cumin FEO, only at the dose of 2%, significantly attenuated the development of morphine tolerance (P < 0.01) and dependence (P < 0.05) while it could be significantly effective on expression of morphine tolerance (1 and 2%) and dependence (0.5, 1 and 2%) in a dose-dependent manner. Solely Cumin FEO injection (0.001–2%) did not show any analgesic effect. In conclusion, the essential oil of Cuminum cyminum seems to ameliorate the morphine tolerance and dependence in mice. 相似文献
23.
Donald H. Gilden Mary Devlin Mary Wellish Ravi Mahalingham Clark Huff Anthony Hayward Abbas Vafai 《Virus genes》1989,2(4):299-305
Varicella-zoster virus (VZV) DNA was detectable by in-situ hybridization in blood mononuclear cells (MNCs) of patients with varicella or zoster for 2–56 days after the onset of a rash. VZV DNA was present in many MNCs from one acute varicella patient 2 days after the onset of the rash and was rarely found in MNCs during acute zoster, convalescent zoster, and convalescent varicella. The morphology of MNCs containing VZV was heterogenous, although most viral-DNA-containing MNCs were large monocytoid cells. Serial examination of blood MNCs from one adult with varicella revealed VZV DNA up until 8 weeks, but not 16 weeks, after the appearance of the rash; parallel studies in four zoster patients showed VZV DNA up until 3 weeks, but not later than 7 weeks after the appearance of the rash. These results indicate that MNCs become infected with VZV during the primary encounter with VZV (varicella) and during reactivation (zoster) and that infection continues for weeks after the onset of the skin rash. Furthermore, the detection of VZV DNA in blood MNCs of uncomplicated zoster patients coincides with the period during which these patients experience pain. 相似文献
24.
25.
Immunologic enhancement of rat renal allografts. III. Immunopathologic lesions and rejection in long-surviving passively enhanced grafts. 总被引:1,自引:0,他引:1
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A. K. Abbas J. M. Corson C. B. Carpenter T. B. Strom J. P. Merrill G. J. Dammin 《The American journal of pathology》1975,79(2):255-270
Immunologic enhancement of renal allografts from (Lewis times Brown Norway) F1 to Lewis rats was achieved by administering a single dose of antidonor serum at the time of transplantation. A series of grafts functioning for 1 to 4 months after transplantation were examined by light and immunofluorescence microscopy to evaluate the long-term protective effects of the enhancing serum and to determine if previously unobserved lesions appeared in long survivors. Despite the absence of detectable circulating cytotoxic alloantibody, long-term allografts showed necrotizing glomerular and arterial lesions which resembled those seen in acutely rejecting grafts and were compatible with humoral rejection. Thus, in this model, there is a late decline in the ability of passive enhancement to inhibit humoral rejection. Long-term grafts also developed tubular lesions with deposition of immunoglobulin and complement on the tubular basement membranes (TBM). Anti-TBM antibodies were demonstrated in recipients' sera and found to be organ specific but not major histocompatibility antigen or species specific. This tubular lesion is therefore a unique form of allograft injury in which the immune response is directed against tissue antigen(s) which are distinct from the major histocompatibility antigens that induce rejection. 相似文献
26.
Mahmud Ahmad Hasan Abbas Sayedul Haque 《American journal of medical genetics. Part A》1993,46(4):369-371
A Pakistani kindred comprising 5 generations contained 9 males and 4 females with alopecia universalis as a single abnormality without any associated defects. The skin biopsy from the scalp showed hair follicles without hair. Analysis of the pedigree is strongly suggestive of autosomal recessive inheritance, and consanguineous loops could account for all affected persons being homozygous for the abnormal allele. © 1993 Wiley-Liss, Inc. 相似文献
27.
Stability of Th1 and Th2 populations 总被引:19,自引:0,他引:19
Perez Victor L.; Lederer James A.; Lichtman Andrew H.; Abbas Abul K. 《International immunology》1995,7(5):869-875
Using an in vitro model for the development of IFN-y-producIng(Th1) and IL-4-produclng (Th1) cells from CD4 T lymphocytesexpressing a transgenlc TCR, we show that IL-12 and IL-4 arethe most potent stimuli for the differentiation of naive T cellsto effector populations. When combinations of cytokines arepresent during T cell priming, the effect of IL-4 Is dominant.Furthermore, differentiated Th1 cells can be converted intoIL-4 producers by exposure to IL-4, but the Th2 phenotype Isnot reversible. The stability of Th2 populations may limit theability to regulate Th2-domlnant responses In pathologic situations. 相似文献
28.
A de novo case of hereditary neuropathy with liability to pressure palsies (HNPP) of maternal origin: a new mechanism for deletion in 17p11.2? 总被引:2,自引:1,他引:2
LeGuern E; Gouider R; Ravise N; Lopes J; Tardieu S; Gugenheim M; Abbas N; Bouche P; Agid Y; Brice A 《Human molecular genetics》1996,5(1):103-106
Hereditary neuropathy with liability to pressure palsies (HNPP) is an
autosomal dominant neuropathy, most often associated with a deletion of the
17p11.2 region, which is duplicated in 70% of patients with Charcot-
Marie-Tooth type 1 (CMT1A). Most de novo CMT1A and HNPP cases have been of
paternal origin. A rare case of de novo HNPP of maternal origin was
analysed to determine the underlying mechanism. Affected individuals in the
family carried a deletion corresponding to the CMT1A/HNPP monomer unit
associated with a rearrangement of the CMT1A-REP sequences. Segregation
analysis of 17p11-p12 markers in the family indicated that the deletion was
not generated by unequal crossing over between homologous 17 chromosomes,
as in de novo cases from paternal origin, but rather by an intrachromosomal
rearrangement. Two distinct mechanisms can therefore lead to the same
17p11.2 deletion. This result suggests that intrachromosomal rearrangement
may be specific to maternal transmissions.
相似文献
29.
Mahmoud Hassanein El-Saied A. Aly Yousf A. Abbas Samia M. El-Sigeny 《Macromolecular chemistry and physics.》1993,194(6):1817-1825
To overcome mass transfer limitations which are usually encountered on immobilizing active catalysts, cationic latex particles were used as support for the cobalt(II) complex of disodium N,N′-bis(salicylidene)ethylenediamine-5,5′-disulfonate ( 1 ). The cationic latex 2 was prepared by emulsion copolymerization of chloromethylstyrene (m/p-isomer mixture 60/40) and divinylbenzene (m/p-isomer mixture) followed by treatment with trimethylamine. The latexbound catalyst from 1 and 2 was found to considerably increase the reaction rate of the autoxidation of 2,6-di-tert-butylphenol in water as compared with the conventional polymer-free system. Reaction products were identified as the oxidative coupling product 3,3′,5,5′-tetra-tert-butyldiphenoquinone (3,3′,5,5′-tetra-tert-butyl-4,4′-dioxo-1,1′-bicyclohexa-2,5-dienylidene) and 2,6-di-tert-butyl-1,4-benzoquinone. All reactions showed an induction period before the start of dioxygen consumption. The rate of autoxidation in the three-phase mixtures of water, latex particles, and phenol droplets was not affected significantly by the method of mixing. The reaction rate increased as the concentration of 1 increased. Increasing the partial pressure of dioxygen in the range between 0,25 and 1,0 atm (2,53. 104 – 1,01. 105 Pa) gave a small increase in rate. The colloidal latex catalyst from 1 and 2 showed some loss of activity after successive runs. 相似文献
30.
Hosal SA Apel RL Freeman JL Azadian A Rosen IB LiVolsi VA Asa SL 《Endocrine pathology》1997,8(1):21-28
Molecular analyses of thyroid tumors have documented mutations in the tumor suppressor p53 gene almost exclusively in anaplastic
carcinomas. In contrast, immunohistochemistry has localized p53 in differentiated papillary and follicular thyroid cancers.
To establish the significance of p53 immunolocalization in these lesions, 78 thyroid tumors of follicular derivation were
examined. All tumors were classified by strict criteria and the extent of tumor was determined morphologically. Immunohistochemical
staining for p53 was performed on paraffin sections of formalin-fixed tumor tissue. The results of staining were correlated
with diagnosis, tumor extent and clinical outcome. Immunopositivity for p53 was diffuse and strong in all five anaplastic
carcinomas examined. There was no staining in five of six follicular adenomas. Four of nine follicular carcinomas had some
degree of nuclear staining, but this was focal; all nine tumors were confined to the thyroid at the time of examination. Of
49 papillary carcinomas, 26 were intrathyroidal, and 7 of these were occult; there was no p53 positivity in any occult lesion
and only 5 of the 19 palpable lesions stained. In contrast, among 23 papillary carcinomas with extrathyroidal extension or
metastases, only 9 were negative for p53 immunoreactivity. Five of seven tall cell papillary carcinomas and one of two insular
carcinomas had p53 immunopositivity and this correlated with aggressive behavior. These results support the tumorigenic role
of p53 mutations postulated for anaplastic thyroid carcinomas and indicate that localization of p53 by immunohistochemistry
is a useful prognostic index of clinical behavior in differentiated thyroid carcinomas of follicular cell derivation. 相似文献