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91.
TJ Newman 《Canadian Metallurgical Quarterly》1995,51(5):4212-4221
92.
SB Christensen A Guider CJ Forster JG Gleason PE Bender JM Karpinski WE DeWolf MS Barnette DC Underwood DE Griswold LB Cieslinski M Burman S Bochnowicz RR Osborn CD Manning M Grous LM Hillegas JO Bartus MD Ryan DS Eggleston RC Haltiwanger TJ Torphy 《Canadian Metallurgical Quarterly》1998,41(6):821-835
Evaluation of a variety of PDE4 inhibitors in a series of cellular and in vivo assays suggested a strategy to improve the therapeutic index of PDE4 inhibitors by increasing their selectivity for the ability to inhibit PDE4 catalytic activity versus the ability to compete for high affinity [3H]rolipram-binding sites in the central nervous system. Use of this strategy led ultimately to the identification of cis-4-cyano-4-[3-(cyclopentyloxy)-4-methoxyphenyl]cyclohexane-1-carboxyl ic acid (1, SB 207499, Ariflo), a potent second-generation inhibitor of PDE4 with a decreased potential for side effects versus the archetypic first generation inhibitor, (R)-rolipram. 相似文献
93.
T cell vaccination induces T cell receptor Vbeta-specific Qa-1-restricted regulatory CD8(+) T cells 总被引:1,自引:0,他引:1
H Jiang H Kashleva LX Xu J Forman L Flaherty B Pernis NS Braunstein L Chess 《Canadian Metallurgical Quarterly》1998,95(8):4533-4537
Vaccination of mice with activated autoantigen-reactive CD4(+) T cells (T cell vaccination, TCV) has been shown to induce protection from the subsequent induction of a variety of experimental autoimmune diseases, including experimental allergic encephalomyelitis (EAE). Although the mechanisms involved in TCV-mediated protection are not completely known, there is some evidence that TCV induces CD8(+) regulatory T cells that are specific for pathogenic CD4(+) T cells. Previously, we demonstrated that, after superantigen administration in vivo, CD8(+) T cells emerge that preferentially lyse and regulate activated autologous CD4(+) T cells in a T cell receptor (TCR) Vbeta-specific manner. This TCR Vbeta-specific regulation is not observed in beta2-microglobulin-deficient mice and is inhibited, in vitro, by antibody to Qa-1. We now show that similar Vbeta8-specific Qa-1-restricted CD8(+) T cells are also induced by TCV with activated CD4(+) Vbeta8(+) T cells. These CD8(+) T cells specifically lyse murine or human transfectants coexpressing Qa-1 and murine TCR Vbeta8. Further, CD8(+) T cell hybridoma clones generated from B10.PL mice vaccinated with a myelin basic protein-specific CD4(+)Vbeta8(+) T cell clone specifically recognize other CD4(+) T cells and T cell tumors that express Vbeta8 and the syngeneic Qa-1(a) but not the allogeneic Qa-1(b) molecule. Thus, Vbeta-specific Qa-1-restricted CD8(+) T cells are induced by activated CD4(+) T cells. We suggest that these CD8(+) T cells may function to specifically regulate activated CD4(+) T cells during immune responses. 相似文献
94.
AIDS-related malignancies (ARM) include AIDS-defining cancers such as Kaposi's sarcoma, non-Hodgkin's lymphoma and cervical carcinoma. In addition, certain other malignancies are also increased with human immunodeficiency virus (HIV) infection. New antiretroviral agents and better prophylaxis and treatment of HIV-related opportunistic infections are prolonging the lives of HIV-infected individuals. There will thus likely be a continued rise in the incidence and prevalence of ARM in the long term, even if effective antiretroviral and other AIDS-related therapies reduce their appearance in the short term. There are presently no curative regimens for the common ARM, with the possible exception of some lymphomas. Survival is shortened by most, and treatment is often toxic and poorly tolerated. Gene therapies may thus offer a useful adjunct to conventional treatment strategies for selected ARM. Although some gene therapy strategies may work well in the HIV setting, the chronic viral infection, immunodeficient status of the host, the tendency for HIV-infected individuals to have altered drug metabolism and an increased rate of adverse drug reactions will likely present special challenges. This review summarizes the state-of-the-art in the fledgling field of gene therapy for ARM, and explores areas for future research. 相似文献
95.
AC Lidral PA Romitti AM Basart T Doetschman NJ Leysens S Daack-Hirsch EV Semina LR Johnson J Machida A Burds TJ Parnell JL Rubenstein JC Murray 《Canadian Metallurgical Quarterly》1998,63(2):557-568
Nonsyndromic cleft lip with or without cleft palate (CL/P) and nonsyndromic cleft palate only (CPO) are common congenital anomalies with significant medical, psychological, social, and economic ramifications. Both CL/P and CPO are examples of complex genetic traits. There exists sufficient evidence to hypothesize that disease loci for CL/P and CPO can be identified by a candidate-gene linkage-disequilibrium (LD) strategy. Candidate genes for clefting, including TGFA, BCL3, DLX2, MSX1, and TGFB3, were screened for LD with either CL/P or CPO in a predominantly Caucasian population, with both case-control- and nuclear-family-based approaches. Previously reported LD for TGFA with both CL/P and CPO could not be confirmed, except in CL/P patients with a positive family history. Also, in contrast to previous studies, no LD was found between BCL3 and either CL/P or CPO. Significant LD was found between CL/P and both MSX1 and TGFB3 and between CPO and MSX1, suggesting that these genes are involved in the pathogenesis of clefting. In addition, a mutation search in the genes DLX2, MSX1, and TGFB3 was performed in 69 CPO patients and in a subset of the CL/P patients. No common mutations were found in the coding regions of these genes; however, several rare variants of MSX1 and TGFB3 were found that may alter the latters' normal function. These results form the basis for future research, including (a) mutation searches in the MSX1 and TGFB3 genes in Caucasian CL/P patients and (b) extension of the search for MSX1 mutations in CPO patients to the noncoding regions. 相似文献
96.
Kartagener's syndrome (KS) usually includes mirror-image dextrocardia. The incidence of congenital heart disease in KS is comparable with that in the general population. This paper reports on a case of Kartagener's syndrome associated with dextrocardia, corrected transposition of the great arteries (I,D,D), ventricular septal defect, and valvar pulmonary stenosis in an 8-year-old girl. 相似文献
97.
U Schiefer M Skalej M Kolb TJ Dietrich R Kolb C Braun D Petersen 《Canadian Metallurgical Quarterly》1998,38(9):1303-1312
An attempt was made to clarify whether the site of postchiasmal lesions affects subjective perception of homonymous visual field defects during stimulation with flickering random dot patterns (white noise-field). Out of 56 patients with homonymous hemianopia, 38 (68%) perceived scotomata in this situation, but 18 (32%) discerned none at all. Neuroradiologic superposition of cerebral lesions detected by computed tomography (CT) or magnetic resonance imaging (MRI) showed that nearly all patients who perceived their scotomata had lesions involving the primary visual cortex or the perigeniculate region, whereas those who received no scotoma had lesions centered within the optic radiation. Functional MRI of six normal subjects during stimulation with flickering random dot patterns indicated predominant activation of the primary visual cortex. Since noise-field defects were most frequently perceived by patients whose lesion involved the primary visual cortex, it appears that the sensitivity of noise-field campimetry depends on the site of damage in the visual pathway. The explanation for this may be that damage to long-range horizontal connections impairs filling-in processes. 相似文献
98.
CY Pai TS Kuo TJ Jaw E Kurant CT Chen DA Bessarab A Salzberg YH Sun 《Canadian Metallurgical Quarterly》1998,12(3):435-446
The Extradenticle (Exd) protein in Drosophila acts as a cofactor to homeotic proteins. Its nuclear localization is regulated. We report the cloning of the Drosophila homothorax (hth) gene, a homolog of the mouse Meis1 proto-oncogene that has a homeobox related to that of exd. Comparison with Meis1 finds two regions of high homology: a novel MH domain and the homeodomain. In imaginal discs, hth expression coincides with nuclear Exd. hth and exd also have virtually identical, mutant clonal phenotypes in adults. These results suggest that hth and exd function in the same pathway. We show that hth acts upstream of exd and is required and sufficient for Exd protein nuclear localization. We also show that hth and exd are both negative regulators of eye development; their mutant clones caused ectopic eye formation. Targeted expression of hth, but not of exd, in the eye disc abolished eye development completely. We suggest that hth acts with exd to delimit the eye field and prevent inappropriate eye development. 相似文献
99.
PURPOSE: We studied the frequency of testicular microlithiasis (TM) in a select group of otherwise healthy infertile men with abnormal semen. METHODS: We reviewed scrotal sonography records of 180 consecutive patients with abnormal semen who were referred for evaluation of male infertility. The pampiniform plexus was evaluated for possible varicocele, and the testes were examined for the presence or absence of intratesticular calcifications and/or masses. Five patients with more than 5 echogenic foci per transducer field in either testis were identified. The medical records and sonograms of this subgroup of patients were analyzed. RESULTS: Of the 180 patients, 5 (2.8%) had TM. Three patients with TM had concomitant small varicoceles; 2 others had a history of testicular maldescent. Two patients eventually became fertile. CONCLUSIONS: Our results indicate a higher than expected frequency of TM in otherwise healthy infertile men. We speculate that the magnitude of hypospermatogenesis in patients with TM is variable and may relate to both the degree of testicular dysgenesis and the presence or absence of concomitant scrotal pathology (eg, scrotal varicocele and cryptorchidism). 相似文献
100.
TJ Christmas AP Doherty GJ Rustin MJ Seckl ES Newlands 《Canadian Metallurgical Quarterly》1997,84(7):1022-1025
BACKGROUND: Primary retroperitoneal germ cell tumours usually present as a large abdominal mass in young men. The testes are normal on examination and ultrasonography but there are usually raised serum levels of human chorionic gonadotrophin and/or alpha-fetoprotein. METHODS: Fourteen men (median age 33 years) with primary retroperitoneal germ cell tumours were treated by chemotherapy followed by surgical resection of the primary tumour and metastases via a thoracoabdominal extraperitoneal approach. RESULTS: There was minimal morbidity. The survival rate was 13 of 14 and the disease-free survival rate was 11 of 14 after a median follow-up of 15 months. CONCLUSION: The thoracoabdominal extraperitoneal approach for the removal of retroperitoneal germ cell tumours and their metastases after chemotherapy improves tumour clearance, morbidity and recovery time compared with the transperitoneal anterior approach. 相似文献