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Astrocytic tumors frequently express Fas/APO-1 (Fas), in sharp contrast to surrounding normal brain cells, providing a potential window through which selective killing of tumor cells could be pursued. To assess this possibility, we transduced Fas into U251, a glioma cell line resistant to anti-Fas antibody-mediated apoptosis, and obtained transfectants with high levels of Fas expression. Anti-Fas antibody showed significantly enhanced cytotoxicity for the transfectants, suggesting that U251 cells maintained an intercellular cascade of Fas-mediated apoptosis. When U251 transfectants with high-level Fas expression were transduced with Fas ligand-encoding gene via retrovirus, they were unaffected by exposure to anti-Fas antibody or Fas ligand adenovirus (Adeno-FL). Thus, retroviral induction of Fas ligand into the glioma cells with high levels of Fas led to the selection of cells that were resistant to Fas-dependent apoptosis. These resistant U251 transfectants were susceptible to FADD adenovirus (Adeno-FADD)-induced apoptosis, indicating that a cascade of death signals was blocked at the steps between Fas ligand and FADD. As for adenoviral transduction of Fas ligand into gliomas, gliomas with a relatively high level of expression of Fas were remarkably sensitive to Adeno-FL-induced apoptosis. Besides, Adeno-FADD induced pronounced apoptosis in all glioma cells. Our data suggest the possibility of using adenovirus-mediated transduction of Fas ligand and FADD genes as a therapeutic approach to target gliomas.  相似文献   

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The expression of full-length dystrophin and various dystrophin deletion mutants was monitored in mdx mouse muscle after intramuscular injection of dystrophin-encoding plasmid DNAs. Recombinant dystrophin proteins, including those lacking either the amino terminus, carboxyl terminus, or most of the central rod domain, showed localization to the plasma membrane. This suggests that there are multiple attachment sites for dystrophin to the plasma membrane. Only those constructs containing the carboxyl terminus were able to stabilize dystrophin-associated proteins (DAP) at the membrane, consistent with other studies that suggest that this domain is critical to DAP binding. Colocalization with DAP was not necessary for membrane localization of the various dystrophin molecules. However, stabilization and co-localization of the DAP did seem to be a prerequisite for expression and/or stabilization of mutant dystrophins beyond 1 wk and these same criteria seemed important for mitigating the histopathological consequences of dystrophin deficiency.  相似文献   

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In summary, several agents have been studied, but only CS and thyroid hormones have been found to accelerate fetal lung maturation in animal studies. Thirty years of research has documented the beneficial effect of antenatal CS on fetal lung maturation, and antenatal steroid in combination with postnatal surfactant remains the mainstay of prevention and therapy for RDS in preterm infants. The efficacy and safety of postnatal steroids have yet to be demonstrated. Unfortunately, the addition of antenatal TRH to this regimen has not provided further benefit to the neonatal outcome of preterm infants as evidenced by the recently completed multicenter trials. In addition, the optimal number of courses of antenatal CS for lung maturation remains unclear.  相似文献   

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There is increasing recognition that stochastic processes regulate highly predictable patterns of gene expression in developing organisms, but the implications of stochastic gene expression for understanding haploinsufficiency remain largely unexplored. We have used simulations of stochastic gene expression to illustrate that gene copy number and expression deactivation rates are important variables in achieving predictable outcomes. In gene expression systems with non-zero expression deactivation rates, diploid systems had a higher probability of uninterrupted gene expression than haploid systems and were more successful at maintaining gene product above a very low threshold. Systems with relatively rapid expression deactivation rates (unstable gene expression) had more predictable responses to a gradient of inducer than systems with slow or zero expression deactivation rates (stable gene expression), and diploid systems were more predictable than haploid, with or without dosage compensation. We suggest that null mutations of a single allele in a diploid organism could decrease the probability of gene expression and present the hypothesis that some haploinsufficiency syndromes might result from an increased susceptibility to stochastic delays of gene initiation or interruptions of gene expression.  相似文献   

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Blood product transfusion therapy and its concomitant risks pose a special challenge for the oncology nurse. Knowledge of the pathophysiology of transfusion reactions, presenting symptoms, and treatment is necessary to safely monitor transfusions. Through meticulous nursing assessment, detection, and intervention, oncology nurses can prevent and/or minimize morbidity and mortality in patients receiving transfusion therapy.  相似文献   

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In most previous reports telomerase activity in lung cancer patients has been detected using tissue extracts. We have developed a semiquantitative fluorescence-based TRAP assay using fluorescence-end-labeling primers. Moreover, we also developed an in situ TRAP assay that detects telomerase activity at the cellular level. Thus, using these TRAP assays, we can detect telomerase activity in lung cancer cells obtained from bronchial washings. A high incidence of lung cancer patients with class I-III cytology had detectable telomerase activity, thus, a combination of a cell extract based. TRAP assay and an in situ TRAP assay may provide additive information to cytology for the diagnosis of lung cancer.  相似文献   

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OBJECTIVE: The purpose of this article is to review evidence that inflammatory and immune mechanisms are important in the pathophysiology of Alzheimer's disease and to suggest new treatment strategies. METHOD: The authors review the English-language literature of the last 10 years pertaining to the pathophysiology of Alzheimer's disease. RESULTS: There is ample evidence supporting the hypothesis that inflammatory and immune mechanisms are involved in tissue destruction in Alzheimer's disease. Acute phase proteins are elevated in the serum and are deposited in amyloid plaques, activated microglial cells that stain for inflammatory cytokines accumulate around senile plaques, and complement components including the membrane attack complex are present around dystrophic neurites and neurofibrillary tangles. CONCLUSIONS: Clinical trials of anti-inflammatory/immunosuppressive drugs are necessary to determine whether alteration of these inflammatory mechanisms can slow the progression of Alzheimer's disease.  相似文献   

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The effector functions of immunoglobulins of the G class (IgGs) are essential for their effective use in therapy. The functions that operate following complex formation with cognate antigen involve binding to C1q (to mediate complement fixation) and the Fc receptors, Fc gamma RI, II and III. Another class of functions that is independent of antigen binding encompasses the transfer of antibodies across the placenta and maintaining the levels in the serum. All effector functions of IgGs are conferred by sequences in the Fc region of antibodies, and this review discusses the localisation of the functions to specific amino acid residues. Such knowledge is of use for the further improvement of IgCs for therapy.  相似文献   

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Cystic fibrosis (CF) has become a paradigm disorder for the clinical testing of gene therapies in the treatment of inherited disease. In recent years, efforts directed at gene therapy of CF have concentrated on improving gene delivery systems to the airway. Surrogate endpoints for complementation of CFTR dysfunction in the lung have been primarily dependent on correction of chloride transport abnormalities. However, it is now clear that the pathophysiology of CF airways disease is far more complex than can be solely attributed to altered chloride permeability. For example, in addition to functioning as a chloride channel, CFTR also has been implicated in the regulation of other apical membrane conductance pathways through interactions with the amiloride sensitive epithelial sodium channel (ENaC) and the outwardly rectifying chloride channel (ORCC). Superimposed on this functional diversity of CFTR is a highly regulated pattern of CFTR expression in the lung. This heterogeneity occurs at both the level of CFTR protein expression within different cell types in the airway and the anatomical location of these cells in the lung. Potential targets for gene therapy of CF include ciliated, non-ciliated, and goblet cells in the surface airway epithelium as well as submucosal glands within the interstitium of the airways. Each of these distinct cellular compartments may have functionally distinct roles in processes which affect the pathogenesis of CF airways disease, such as fluid and electrolyte balance. However, it is presently unclear which of these cellular targets are most pathophysiologic relevant with regard to gene therapy. Elucidation of the underlying mechanisms of CFTR function in the airway will allow for the rational design of gene therapy approaches for CF lung diseases. This review will provide a summary of the field's current knowledge regarding CFTR functional diversity in the airway and the implications of such diversity for gene therapies of CF lung disease.  相似文献   

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The electrical activity resulting from stimulation by motor neurons regulates gene expression in skeletal muscle fibres. A recent study has suggested a mechanism by which distinct patterns of electrical stimulus might be integrated to control the contractile properties of these fibres.  相似文献   

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This review discusses the known cardiovascular effects of smoking and the effects of nicotine without tobacco smoke and interprets the available data on cardiovascular risk during nicotine replacement therapy (NRT). Nicotine gum and patches are now approved for over the counter sale in the United States. Smokers with cardiovascular disease are advised to seek physician counseling before using nicotine products, but information regarding the safety of these products in such patients is not readily available to most physicians. Nicotine may contribute to cardiovascular disease, presumably by hemodynamic consequences of sympathetic neural stimulation and systemic catecholamine release. However, there are many potential cardiovascular toxins in cigarette smoke other than nicotine. The doses of nicotine obtained by regular cigarette smoking generally exceed those delivered by NRTs, and the cardiovascular effects of nicotine are, in general, more intense when delivered rapidly by cigarette smoking than the slower delivery by transdermal nicotine or nicotine gum. Because the dose-cardiovascular response relation for nicotine is flat, the effects of cigarette smoking in conjunction with NRT are similar to those of cigarette smoking alone. Cigarette smoking increases blood coagulability, a major risk factor for acute cardiovascular events, whereas transdermal nicotine does not appear to do so. Clinical trials of NRT in patients with underlying, stable coronary disease suggest that nicotine does not increase cardiovascular risk. At worst, the risks of NRT are no more than those of cigarette smoking. The risks of NRT for smokers, even for those with underlying cardiovascular disease, are small and are substantially outweighed by the potential benefits of smoking cessation.  相似文献   

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The gene therapy strategy using the hsvl-thymidine kinase gene (TK) and ganciclovir (GCV) injections that has been used for treating human glioblastomas has not been as effective as expected after the first animal experiments. A better understanding of the different steps involved in this treatment, like gene transfer, gene expression, and sensitivity of the recipient cells, is needed. After proposing sensitivity criteria for the TK/GCV system and for the bystander effect, based on the levels of GCV that can be reached in vivo, we studied seven human glioblastoma cell lines (U87, U118, U251, SNB19, SNB75, SF295, SF539) for their sensitivity to the TK/GCV system. We also studied their in vitro bystander effect and their in vitro transfectability using LipofectAMINE as a transfection enhancer. Among six human glioblastoma cell lines stably transfected with the TK gene, five were sensitive to TK/GCV, and two had a good in vitro bystander effect. The in vitro transfectability of the cell lines tested was low (< or = 1%) compared to that of an established animal cell line, C6 rat glioma, in which 20-30% of the cells can be transfected routinely. According to this in vitro analysis, most of the glioblastoma cell lines should be sensitive to the TK/GCV system, but there is an urgent need for agents to increase transfection efficiency.  相似文献   

15.
The Fourier transform infrared spectrum of H3SiI has been recorded in the nu1/nu4 region from 2075 to 2315 cm-1 at an optical resolution of 2.3 x 10(-3) cm-1. The nu1/nu4 fundamental bands and the (nu1 + nu3) - nu3/(nu4 + nu3) - nu3 hot bands have been rotationally investigated. Numerous local perturbations have been observed in the nu1 and nu4 bands and in the hot bands. Without the lines involved in perturbations, more than 2900 transitions of the nu1/nu4 bands were used to determine the band origins and the vibration-rotation parameters of the nu1 = 1 and nuv4 = 1 states. A least-squares fit of 766 apparently unperturbed transitions of the hot bands gave the parameters of the nu1 = nu3 = 1 and nu4 = nu3 = 1 states. The l(2, 2) resonance in nu4 and the A1-E Coriolis coupling between nu1 and nu4 have been investigated. Most of the local perturbations have been studied individually using a simple model by which the main perturber for each resonance was identified. Copyright 1998 Academic Press.  相似文献   

16.
We conducted a prospective, nonrandomized study in healthy volunteers to determine if racial differences exist in orosomucoid (ORM) and its variants, and to examine quinidine and lidocaine binding to the protein. Total ORM serum concentrations were measured by Laurell-Rocket immunoelectrophoresis. Allele types were determined by isoelectric focusing and immunoblotting. Total and unbound quinidine and lidocaine concentrations were measured with standard fluorescence polarization immunoassays after ultrafiltration. The frequency of the common ORM alleles was similar between 38 Caucasians and 67 African-Americans. Mean total ORM concentration was significantly lower in Caucasians (57.3 +/- 25.4 vs 73.2 +/- 33.9 mg/dl, p=0.01). However, more Caucasians took oral contraceptives, which may have decreased ORM concentrations. Quinidine unbound fraction (UF) was related to ORM phenotype. The highest UF was found with ORM 1-S (p=0.009). There were no significant relationships between ORM phenotype and lidocaine UF. Overall, African-Americans had higher ORM concentrations than Caucasians. Quinidine binding showed significant relationships to specific ORM variants.  相似文献   

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This paper develops the basic premise that learning to self-regulate a pattern of responses can have different consequences from those observed when controlling individual functions alone. It is suggested that the self-regulation of patterns of responses can be a particularly sensitive and effective procedure for (a) uncovering biological linkages and constraints between responses in the intact human, (b) investigating how multiphysiological systems combine to produce unique subjective experiences and effects on performance, and (c) enhancing the clinical effectiveness of biofeedback procedures by training patients to integrate and coordinate voluntarily specific patterns of cognitive, autonomic, and motor responses. These hypotheses are illustrated by basic research involving biofeedback training for patterns of blood pressure, heart rate and EEG activity, related experiments on the cognitive self-regulation of patterns of physiological responses using affective imagery and meditation procedures, and case studies of patients treated with biofeedback. The concept of electronic biofeedback as an "unnatural act" is presented with the goal of placing self-regulation within a more biobehavioral perspective emphasizing the natural patterning of physiological processes.  相似文献   

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BACKGROUND: Epithelial ovarian tumors of borderline malignancy are different from benign tumors and malignant neoplasms. They exist with relatively benign clinical course, younger age and better prognosis as compared with invasive malignant carcinomas. Most of them are discovered at early stage, for example, stage Ia. This retrospective review evaluates the clinical features, treatments and prognosis of 48 patients with borderline malignancy of ovarian tumors. METHODS: Forty-eight patients with ovarian tumors of borderline malignancy, aged from 14 to 69 years (mean: 39.2 years; median: 36 years), were retrospectively studied. The histopathologic diagnosis was based on the morphologic criteria published by Tazelaar et al. in 1985. All cases, including 16 cases diagnosed before 1985, were pathologically reviewed. All information of clinical stage, surgical intervention and prognosis was achieved by reviewing hospital record or contacting patients by telephone. Two patients were lost to follow up. One patient died of sepsis resulting from another operation for another gynecological cancer. Totally forty-five patients were included for evaluation. RESULTS: Thirty-nine of the 48 patients (81.3%) were at stage Ia, 6 cases (12.5%) were at stage Ib, 2 cases (4.1%) were at stage Ic, and the remaining one patient (2.1%) was at state IIIc. Thirty-four patients (71%) were with mucinous cystadenoma of borderline malignancy, 11 cases (23%) were of serous type, and 3 patients (6%) were of mixed serous and mucinous type. Twenty-two patients underwent total abdominal hysterectomy and bilateral salpingo-oophorectomy (TAH and BSO), but one of them remained partial ovary due to young age (27 y/o). Twelve patients were treated with unilateral oophorectomy or unilateral salpingo-oophorectomy (USO). Twelve patients underwent USO and wedge resection of contralateral ovary. One case underwent debulking surgery. One patient underwent enucleation of ovarian tumor and biopsy of contralateral ovary. Eighteen patients were treated with chemotherapy after operation. One patient developed recurrence 4 months after the primary operation. Excluding two cases lost to follow up and one case with surgical mortality for another gynecological cancer, forty-five patients were alive and were followed from 9 months to 165 months. (median: 48 months; mean: 46 months) CONCLUSIONS: Most of the patients were at the early stage of disease when first diagnosed, 81.3% were at stage Ia and only one case was at stage IIIc. Sixty-three percent of our patients underwent surgical treatment alone while the rest of them (37%) had post-operative chemotherapy with either alkeran or PAC. The use of adjuvant chemotherapy seemed unwarranted as there was no difference in survival between those with and without it. (P > 0.05) The low recurrent rate of 2% in our patients again confirmed the 9 P relative benign clinical course of this disease.  相似文献   

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The past five years have witnessed tremendous growth in the field of gene therapy, with pre-clinical and clinical gene therapy trials for diseases as diverse as cancer, AIDS and atherosclerosis. These studies have utilized many different vectors and target organs in order to achieve therapeutic effects. In this review, we examine the rationale for using skeletal muscle as a target tissue for gene therapy, discuss the wide array of vectors that have been used for muscle-based gene therapy, summarize the disease-targets that have been approached using these techniques, and discuss some of the obstacles that remain to be overcome en route to successful muscle-based human gene therapy.  相似文献   

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