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71.
Eduardo C. Salido Merry B. Passage Pauline H. Yen Larry J. Shapiro T. K. Mohandas 《Somatic Cell and Molecular Genetics》1993,19(1):65-71
The expression of mouseZfx, Rps4, Ube1x, andXist was evaluated in hamstermouse somatic cell hybrids containing either an active or an inactive mouse X chromosome using polymerase chain reaction of reverse transcribed RNA (RT-PCR). The results showed thatZfx, Rps4, andUbe1x are expressed exclusively from the active mouse X, whileXist is expressed exclusively from the inactive X. These findings confirm the pattern of X inactivation for these mouse genes reported previously based on expression in somatic tissues of F1 females from interspecific crosses. These results demonstrate the existence of differences between human and mouse X inactivation, as the corresponding human genes,ZFX, RPS4X, andUBE1 escape X inactivation. 相似文献
72.
Major histocompatibility complex status in breast carcinogenesis and relationship to apoptosis 总被引:2,自引:0,他引:2
Redondo M García J Villar E Rodrigo I Perea-Milla E Serrano A Morell M 《Human pathology》2003,34(12):1283-1289
Major histocompatibility complex (MHC) molecules are of central importance in regulating the immune response against tumors. In this study we used immunohistochemistry to study human leukocyte antigen (HLA) class I and II antigen expression in normal breast tissues and benign, preneoplastic, primary, and metastatic breast lesions using antibodies against beta-2-microglobulin (beta2-m), heavy-chain, and HLA-DR antigens. Whereas all normal tissues and benign lesions were positive for beta2-m and HLA-A, -B, and -C antigens, total loss of HLA class I antigens was found in 37% (11 of 30) of in situ carcinomas, in 43% (56 of 131) of the primary tumors, and in 70% (31 of 45) of the lymph node metastases. HLA-DR was also underexpressed in breast cancer cells; thus 20% (6 of 30) of in situ carcinomas, 15% of invasive carcinomas (20 of 131), and only 1 metastatic case were positive for this antigen. Both HLA class I and II antigen expression were more frequently down-regulated in metastatic lesions than in primary breast lesions (P <0.05), and a tendency toward a simultaneous defective expression of HLA class I and II antigens was observed in primary carcinomas (P = 0.07). However, no correlation was found between the expression of any of the aforementioned molecules and pathological parameters or survival. Interestingly, HLA class I expression was expressed more frequently in tissues with high apoptotic activity and was significantly associated with the expression of the proapoptotic bax gene (P = 0.02), and was inversely associated with expression of the antiapoptotic bcl-2 gene (P = 0.03). We conclude that alterations in HLA class I and II antigen expression are early events in breast carcinogenesis and play significant roles in metastatic progression. In addition, their expression is correlated with apoptosis-regulating proteins, which may influence the cytotoxicity of T cells against HLA class I-specific tumor antigens. 相似文献
73.
Villalba-Caloca J García-García Mde L Sifuentes-Osornio J Sada-Díaz E Salazar-Lezama MA 《Gaceta médica de México》2003,139(5):471-492
Tuberculosis is a public health problem. If the current trends continue, is expected to arrive to 10.2 million of new cases in 2005. There are three studies accomplished in 1995 in Mexican patients. The results show important difficulty in the application and the follow-up of the program of control of the tuberculosis, what has caused accumulation of chronic cases, moderate rate of primary resistance and alarming levels of primary and secondary multiresistance (23%). Mechanism of protective immunity against mycobacterium tuberculosis (MTB) in humans have not been clarified. Different subpopulations of lymphocytes CD4, CD8 and other populations as well as macrophages, and monocytes, have an important role. In industrialized countries, the managing of the MDRTB is based on the use of individualized treatments with second line drugs according to susceptibility test, however the foregoing has not been possible to apply it middle or low income countries. WHO has launches the initiative "DOTS plus" that consist in the administration of a standarized regimen on the basis of epidemiology of resistance in the country or region. 相似文献
74.
Marco Sparaco Eric A. Schon Salvatore DiMauro Eduardo Bonilla 《Brain pathology (Zurich, Switzerland)》1995,5(2):125-133
Myoclonic epilepsy with ragged-red fibers (MERRF) is a maternally inherited disorder of oxidative phos-phorylation due to specific point mutations within the mitochondrial tRNALvs gene. Mitochondrial dysfunction in the central nervous system (CNS) of patients with MERRF accounts for the neurological manifestations of the disease. Antibodies against subunits of complex I, III, IV and V of the respiratory chain were used to study the expression of these proteins in the frontal cortex, cerebellum and medulla from an autoptic case of MERRF. We found a selective decreased expression of subunit II of cytochrome c oxidase (COX-II) in these regions. Immunohistochemical abnormalities were more widespread than the lesions described by traditional histopathological techniques and made possible an attempt of explanation for the neurological symptoms of the patient. 相似文献
75.
Central chemoreceptors and sympathetic vasomotor outflow 总被引:1,自引:1,他引:1
Thiago S. Moreira Ana C. Takakura Eduardo Colombari Patrice G. Guyenet 《The Journal of physiology》2006,577(1):369-386
The present study explores how elevations in brain P CO2 increase the sympathetic nerve discharge (SND). SND, phrenic nerve discharge (PND) and putative sympathoexcitatory vasomotor neurons of the rostral ventrolateral medulla (RVLM) were recorded in anaesthetized sino-aortic denervated and vagotomized rats. Hypercapnia (end-expiratory CO2 from 5% to 10%) increased SND (97 ± 6%) and the activity of RVLM neurons (67 ± 4%). Injection of kynurenic acid (Kyn, ionotropic glutamate receptor antagonist) into RVLM or the retrotrapezoid nucleus (RTN) eliminated or reduced PND, respectively, but did not change the effect of CO2 on SND. Bilateral injection of Kyn or muscimol into the rostral ventral respiratory group (rVRG-pre-Bötzinger region, also called CVLM) eliminated PND while increasing the stimulatory effect of CO2 on SND. Muscimol injection into commissural part of the solitary tract nucleus (commNTS) had no effect on PND or SND activation by CO2 . As expected, injection of Kyn into RVLM or muscimol into commNTS virtually blocked the effect of carotid body stimulation on SND in rats with intact carotid sinus nerves. In conclusion, CO2 increases SND by activating RVLM sympathoexcitatory neurons. The relevant central chemoreceptors are probably located within or close to RVLM and not in the NTS or in the rVRG-pre-Bötzinger/CVLM region. RVLM sympathoexcitatory neurons may be intrinsically pH-sensitive and/or receive excitatory synaptic inputs from RTN chemoreceptors. Activation of the central respiratory network reduces the overall sympathetic response to CO2 , presumably by activating barosensitive CVLM neurons and inhibiting RTN chemoreceptors. 相似文献
76.
Molina-Holgado E Guaza C Borrell J Molina-Holgado F 《BioDrugs : clinical immunotherapeutics, biopharmaceuticals and gene therapy》1999,12(5):317-326
This review aims to improve understanding of the modulatory effects that cannabinoids exert on the immune system and CNS. Cannabinoids possess immunomodulatory activity, are neuroprotective in vivo and in vitro and can modify the production of inflammatory mediators, such as nitric oxide, prostanoids and cytokines, that are expressed by, and act on, the immune system and the brain. The mechanisms of cannabinoid actions are not fully understood, but appear to involve complex interactions between cannabinoid receptors and a number of signal transduction pathways. Endogenous cannabinoid ligands appear to act as local modulators of immune/inflammatory reactions. Cannabinoid-induced immunosuppression may have implications for the treatment of neurological disorders that are associated with excess immunological activity, such as multiple sclerosis and Alzheimer's disease. There is anecdotal evidence that cannabis use improves the symptoms of multiple sclerosis, and studies with animal models are beginning to provide evidence for the mechanism of such effects. The development of nonpsychotropic cannabinoid analogues and modulators of the metabolism of endogenous cannabinoid ligands may lead to novel approaches to the treatment of neurodegenerative disorders. 相似文献
77.
78.
Serrano-Brambila EA Camacho-Carvajal JC Moreno-Aranda J Martínez-Sánchez R 《Gaceta médica de México》2003,139(5):435-448
This device consists of a woven in a form of a tubular mesh, made up for the use in the urethra. We report the clinical and uroflujometric results in 10 patients with urethral stricture and 4 with obstructive prostatic hyperplasia. The study includes a 7 year period since October of 1993 up until June 2000. All patients were evaluated pre and post stent insertion with periodic follow ups to assess the prostatic symptoms score, quality of life assessment, peak urinary flow rate, mean flow rate and post-void residual urine volume. The results were the following: For the group with urethral stricture the I-PSS decreased from 26.8 to 5.4 points, the peak flow rate increased from 8.24 to 16.12 mL/sec and the post-void residual urine volume decreased from 42.7 to 31.6 mL. By 12-month follow-up most endoprostheses were 90% covered with urothelium, only one of these patients required stent extraction with no sphincter lesion. For the prosthatic hyperplasia group the I-PSS decreased from 20.2 to 8 points. The peak flow rate increased from 6.95 to 14.5 mL/sec and the post-void residual urine volume decreased from 49 to 18.3 mL. By 12-month follow-up two patients were 95% covered with epithelium, and the other two were 70%. There have not been significant problems related to infections, migration, incontinence or erectile disfunction. An 80% of patients have shown some irritative symptoms (urgency, frequency or dysuria) at least during the first month after stent insertion. These 7 year results suggest that Urolume urethral endoprostheses can be a long-term effective treatment alternative to these patients. 相似文献
79.
Immune responses induced by the Leishmania (Leishmania) donovani A2 antigen,but not by the LACK antigen,are protective against experimental Leishmania (Leishmania) amazonensis infection 下载免费PDF全文
Coelho EA Tavares CA Carvalho FA Chaves KF Teixeira KN Rodrigues RC Charest H Matlashewski G Gazzinelli RT Fernandes AP 《Infection and immunity》2003,71(7):3988-3994
Leishmania amazonensis is one of the major etiologic agents of a broad spectrum of clinical forms of leishmaniasis and has a wide geographical distribution in the Americas, which overlaps with the areas of transmission of many other Leishmania species. The LACK and A2 antigens are shared by various Leishmania species. A2 was previously shown to induce a potent Th1 immune response and protection against L. donovani infection in BALB/c mice. LACK is effective against L. major infection, but no significant protection against L. donovani infection was observed, in spite of the induction of a potent Th1 immune response. In an attempt to select candidate antigens for an American leishmaniasis vaccine, we investigated the protective effect of these recombinant antigens (rLACK and rA2) and recombinant interleukin-12 (rIL-12) against L. amazonensis infection in BALB/c mice. As expected, immunization with either rA2-rIL-12 or rLACK-rIL-12 induced a robust Th1 response prior to infection. However, only the BALB/c mice immunized with rA2-rIL-12 were protected against infection. Sustained gamma interferon (IFN-gamma) production, high levels of anti-A2 antibodies, and low levels of parasite-specific antibodies were detected in these mice after infection. In contrast, mice immunized with rLACK-rIL-12 displayed decreased levels of IFN-gamma and high levels of both anti-LACK and parasite-specific antibodies. Curiously, the association between rA2 and rLACK antigens in the same vaccine completely inhibited the rA2-specific IFN-gamma and humoral responses and, consequently, the protective effect of the rA2 antigen against L. amazonensis infection. We concluded that A2, but not LACK, fits the requirements for a safe vaccine against American leishmaniasis. 相似文献
80.
Bone-specific antibodies in sera from patients with celiac disease: characterization and implications in osteoporosis 总被引:5,自引:0,他引:5
Sugai E Cherñavsky A Pedreira S Smecuol E Vazquez H Niveloni S Mazure R Mauriro E Rabinovich GA Bai JC 《Journal of clinical immunology》2002,22(6):353-362
Osteopenia and osteoporosis are well-known complications detected in celiac disease patients with still obscure pathogenesis. In the present study we investigated the presence of circulating anti-bone autoantibodies in patients with celiac disease and explored their role in the associated bone disease. We evaluated serum samples from 33 patients at the time of diagnosis and from 20 of them after treatment. Sera from patients with inflammatory bowel disease (n = 9), nonceliac osteoporotic (n = 18), and healthy individuals (n = 10) were used as controls. The presence of IgA specific anti-bone antibodies was first investigated using indirect immunofluorescence on cryosections of fetal rat tibia (20-day pregnancy). Furthermore, samples were homogenized and total tissue extracts were subjected to Western blot analysis to confirm immunoreactivity. At diagnosis, sera from 51.5% (17/33) of celiac patients had antibodies that recognized antigenic structures in chondrocytes and the extracellular matrix along mature cartilage, bone interface, and perichondrium of fetal rat bone. Among controls, only two osteoporotic patients showed very low titles of anti-bone autoantibodies. The immunostaining was localized in areas where an active mineralization process occurred and was similar to the distribution of the native bone tissue transglutaminase. The frequency of patients with positive baseline titers of anti-bone antibodies diminished significantly after treatment (P = 0.048). Western blot assays confirmed the presence of autoantibodies in sera from patients with a positive immunofluorescence staining. Autoantibodies recognized a major protein band on tissue extracts with a molecular weight of 77–80 kDa, which could be displaced when sera were preadsorbed with human recombinant tissue transglutaminase. We provide original evidence that patients with celiac disease have IgA-type circulating autoantibodies against intra- and extracellular structures of fetal rat tibia. Our findings suggest that these antibodies recognize bone tissue transglutaminase as the autoantigen, and based on the localization of the immunoreactivity we speculate that they might have an active role in the pathophysiology of celiac disease-associated bone complications. 相似文献