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M Tavio G Nasti C Simonelli E Vaccher P De Paoli M Giacca U Tirelli 《Canadian Metallurgical Quarterly》1998,34(10):1634-1637
To evaluate the antineoplastic activity of human chorionic gonadotropin (hCG) in the treatment of HIV-related Kaposi's sarcoma (KS), two clinical trials focusing on two different schedules of administration and types of hCG preparation were conducted. In the low-dose group, hCG (Profasi-HP) was administered three times a week intramuscularly at a dose ranging from 4000 to 32,000 IU for 4 months and no objective response was observed among 5 evaluable patients. In the high-dose group, hCG (Gonadotrafon) was given intramuscularly three times a week at a dose ranging from 100,000 to 300,000 IU for 3 months with 1 partial response among 8 evaluable patients. In 6 patients evaluated for HIV viral load, no significant reduction in HIV viraemia was observed. In conclusion, hCG showed very limited activity against KS and no influence on HIV viral load, along with emerging dose-limiting toxicity and high cost of the therapy. 相似文献
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DE McCloskey RA Casero PM Woster NE Davidson 《Canadian Metallurgical Quarterly》1995,55(15):3233-3236
The need for antineoplastic compounds with novel mechanisms of action is great. One such agent is the recently synthesized polyamine analogue N1-ethyl-N11-((cyclopropyl)methyl)-4,8-diazaundecane (CPENSpm). Exposure of hormone-dependent and -independent human breast cancer cells to 0.1-10 microM CPENSpm led to both growth inhibition and induction of programmed cell death. Fragmentation of DNA to high molecular weight fragments and oligonucleosomal-sized fragments, both characteristic of programmed cell death, was determined to be time and concentration dependent. Depletion of natural polyamine pools and accumulation of the analogue was also demonstrated. These data provide the first evidence that a polyamine analogue induces programmed cell death. 相似文献
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DE McCloskey J Yang PM Woster NE Davidson RA Casero 《Canadian Metallurgical Quarterly》1996,2(3):441-446
The naturally occurring polyamines putrescine, spermidine, and spermine are required for cell growth. Based on this requirement, several polyamine analogues that interfere with polyamine function and metabolism have been synthesized as antineoplastic agents. The symmetrically substituted N1,N12-bis(ethyl)spermine (BESpm), and unsymmetrically substituted N1-ethyl-N11-[(cyclopropyl)methyl]-4, 8-diazaundecane (CPENSpm) have previously been shown to cause rapid cytotoxicity of NCI H157 cells, with concurrent high induction of the polyamine catabolic enzyme spermidine/spermine N1-acetyltransferase. However, the precise mechanism(s) of the cytotoxic action of the compounds is not known. We now demonstrate that treatment with either BESpm or CPENSpm results in morphological and biochemical changes consistent with the activation of programmed cell death pathways, and that the unsymmetrically substituted CPENSpm more rapidly activates the death program. These studies suggest that the cell type-specific cytotoxicity of these polyamine analogues may be a result of their ability to selectively activate the cell death pathway in sensitive phenotypes and indicate that the relationship between the structure of the polyamine analogues and the ability to induce programmed cell death should be investigated. 相似文献
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Human chorionic gonadotropin (hCG) inhibits the progression of 7,12-dimethylbenz[a]anthracene (DMBA) induced mammary carcinomas. In order to determine whether this phenomenon was mediated by induction of programmed cell death or apoptosis, 45-day-old virgin Sprague-Dawley rats received 8 mg DMBA/100 g body weight; 20 days later they were injected daily with 100 IU hCG for 40 days (DMBA + hCG group). Age-matched untreated, hCG- and DMBA + saline treated rats were used as controls. Tissues were collected at the time of DMBA administration and at 5, 10, 20 and 40 days of hCG injection. RNA from mammary glands, adenocarcinomas and ovaries was probed for transforming growth factors (TGF) alpha and beta, and the apoptotic genes TRPM2, ICE, bcl2, bcl-XL, bcl-XS, p53 and c-myc. The mammary glands of hCG-treated animals with or without DMBA exhibited elevated expression of TRPM2, ICE, bcl-XS, c-myc and p53; and elevation in the apoptotic index. Mammary adenocarcinomas developed in those animals treated with hCG showed an elevation in the expression of p53, c-myc and ICE genes in comparison with the levels detected in the adenocarcinomas developed by the animals treated with DMBA alone. No significant alterations in the expression of any of the genes tested was observed in ovarian RNAs. These results led us to conclude that hCG induces programmed cell death in the mammary gland initiated in the carcinogenic process, that this process is p53 dependent, and is modulated by c-myc expression. Our data also indicate the possibility that a cell death program dependent on the bcl2 family exists, because of the potential involvement of p53, bcl-XS and Bax in apoptosis. This additional mechanism of tumor inhibition makes hCG treatment a useful approach for the prevention and therapy of breast cancer. 相似文献
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H Hibasami T Komiya Y Achiwa K Ohnishi T Kojima K Nakanishi Y Sugimoto M Hasegawa R Akatsuka Y Hara 《Canadian Metallurgical Quarterly》1998,1(4):725-727
The exposure of human stomach cancer KATO III cells to black tea theaflavin extract, free theaflavin, and theaflavin digallate that are main components of the extract, led to both growth inhibition and the induction of programmed cell death (apoptosis). Morphological changes showing apoptotic bodies were observed in the cells treated with black tea theaflavin extract, theaflavin and theaflavin digallate. The fragmentations by these theaflavin compounds of DNA to oligonucleosomal-sized fragments that are characteristics of apoptosis were observed to be concentration- and time-dependent. These data suggest that drinking of black tea in large amounts is recommended to protect humans from stomach cancer. 相似文献
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Frontal sharp waves (encoches pointues frontales) identified by Monod (1960) were studied in 110 neonates and infants. Three pattern were described: typical, related and degraded. They were recorded in all subjects, the reason why the frequency of each pattern varied was discussed. Pathological states did not increase the occurrence of those frontal sharp waves since most of them were recorded in children either normal or suffering from a minor pathology. Incidence of maturation seemed to be probable since the highest proportion of frontal sharp waves occurred in infants whose gestational and legal age were respectively greater than 43 weeks and between 20 and 40 days at the time of investigation. Typical and degraded forms were predominant in transitional period towards quiet sleep; they were less numerous during falling asleep in active sleep and totally absent during active sleep following quiet sleep. This could suggest that the two states of active sleep are different in nature. 相似文献
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ES Pizer C Jackisch FD Wood GR Pasternack NE Davidson FP Kuhajda 《Canadian Metallurgical Quarterly》1996,56(12):2745-2747
One of the key limiting factors in the treatment of advanced stage human epithelial malignancies is the lack of new, selective molecular targets for antineoplastic therapy. A substantial subset of human breast, ovarian, endometrial, colorectal, and prostatic cancers express elevated levels of fatty acid synthase, the major enzyme required for endogenous fatty acid biosynthesis, and carcinoma lines are growth inhibited by cerulenin, a noncompetitive inhibitor of fatty acid synthase. We have shown previously that the difference in fatty acid biosynthesis between cancer and normal cells is an exploitable target for metabolic inhibitors in the in vitro setting and in vivo in a human ovarian carcinoma xenograft in nude mice. Here, we report that cerulenin treatment of human breast cancer cells inhibits fatty acid synthesis within 6 h after exposure, that loss of clonogenic capacity occurs within the same interval, and that DNA fragmentation and morphological changes characteristic of apoptosis ensue. 相似文献
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Hyperthyroidism or increased thyroid function has been reported in many patients with trophoblastic tumors. In these cases, greatly increased human chorionic gonadotropin (hCG) levels and suppressed TSH levels suggest that hCG has thyrotropic activity. Recent investigations have clarified the structural homology not only in the hCG and TSH molecules but also in their receptors, and this homology suggests the basis for the reactivity of hCG with the TSH receptor. The clinical significance of the thyrotropic action of hCG is now also recognized in normal pregnancy and hyperemesis gravidarum. Highly purified hLH binds to recombinant hTSH receptor and is about 10 times as potent as purified hCG in increasing cAMP. The beta-subunits of hCG and hLH share 85% sequence identity in their first 114 amino acids but differ in the carboxy-terminal peptide because hCG beta contains a 31-amino acid extension (beta-CTP). A recombinant mutant hCG that lacks beta-CTP showed almost identical potency to LH on stimulation of recombinant hTSH receptor. If intact hCG were as potent as hLH in regard to its thyrotropic activity, most pregnant women would become thyrotoxic. One of the roles of the beta-CTP may be to prevent overt hyperthyroidism in the first trimester of pregnancy when a large amount of hCG is produced by the placenta. Nicked hCG preparations, obtained from patients with trophoblastic disease or by enzymatic digestion of intact hCG, showed approximately 1.5- to 2-fold stimulation of recombinant hTSH receptor compared with intact hCG. This suggests that the thyrotropic activity of hCG may be influenced by the metabolism of the hCG molecule itself. Deglycosylation and/or desialylation of hCG enhances its thyrotropic potency. Basic hCG isoforms with lower sialic acid content extracted from hydatidiform moles were more potent in activating adenylate cyclase, and showed high bioactivity/immunoactivity (B/I) ratio in CHO cells expressing human TSH receptors. This is consistent with the finding that the beta-CTP truncated hCG with higher thyrotropic potency is substantially deglycosylated and desialylated in the beta-subunit relative to intact hCG because all four O-linked glycosylation sites occur within the missing C-terminal extension. The desialylated hCG variant also interacts directly with recombinant hTSH receptors transfected into human thyroid cancer cells. There is thyroid-stimulating activity in sera of normal pregnant women, and this correlates with serum hCG levels. The thyroid gland of normal pregnant women may be stimulated by hCG to secrete slightly excessive quantities of T4 and induce a slight suppression of TSH, perhaps being about 1 mU/L less than nongravid levels, but not high enough to induce overt hyperthyroidism. Maternal thyroid glands may secrete more thyroid hormone during early pregnancy in response to the thyrotropic activity of hCG that overrides the normal operation of the hypothalamic-pituitary-thyroid feedback system. Biochemical hyperthyroidism associated with hyperemesis gravidarum has been attributed to hCG. In patients with hyperemesis gravidarum, thyrotropic in serum correlated with hCG immunoreactivity, and the severity of vomiting as indicated by clinical and biochemical parameters correlated with the degree of thyroid stimulation. To understand the thyrotropic action of hCG, it is necessary to know whether hCG activates the same domain of the TSH receptor as does TSH. The identification of the molecular structure of the hCG isoform with the highest thyrotropic potency will resolve the enigma of gestational thyrotoxicosis and the hyperthyroidism associated with trophoblastic disease and hCG-producing tumors. 相似文献
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Human chorionic gonadotropin preparations were tested for their effect on protein metabolism by cultured fibroblasts. Commercial preparations of HCG strongly inhibit amino acid uptake and incorporation into protein by a variety of human adult and fetal fibroblast lines, whereas, highly purified HCG is without such an effect. 相似文献
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We conducted a study to evaluate risk factors for developing typhoid fever in a setting where the disease is endemic in Karachi, Pakistan. We enrolled 100 cases with blood culture-confirmed Salmonella typhi between July and October 1994 and 200 age-matched neighbourhood controls. Cases had a median age of 5.8 years. In a conditional logistic regression model, eating ice cream (Odds ratio [OR] = 2.3; 95% confidence interval [CI] 1.2-4.2, attributable risk [AR] = 36%), eating food from a roadside cabin during the summer months (OR = 4.6, 95% CI 1.6-13.0; AR = 18%), taking antimicrobials in the 2 weeks preceding the onset of symptoms (OR = 5.7, 95% CI 2.3-13.9, AR = 21%), and drinking water at the work-site (OR = 44.0, 95% CI 2.8-680, AR = 8%) were all independently associated with typhoid fever. There was no difference in the microbiological water quality of home drinking water between cases and controls. Typhoid fever in Karachi resulted from high-dose exposures from multiple sources with individual susceptibility increased by young age and prior antimicrobial use. Improving commercial food hygiene and decreasing unnecessary antimicrobial use would be expected to decrease the burden of typhoid fever. 相似文献
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OBJECTIVE: To investigate free alpha-human chorionic gonadotropin (hCG) as a marker of preeclampsia. METHODS: Four groups of patients were studied: normal pregnancies, preeclampsia, eclampsia and normal pregnant women <20 weeks' gestation. Patients were further divided according to parity and gestational age (< or =20, 21-30, 31-40 weeks). An immunoradiometric assay employing monoclonal antibodies specific for free alpha-hCG was used. RESULTS: A total of 313 patients were analyzed. Thirty-four patients < or =20 weeks' gestation were followed until delivery: five (14.7%) developed preeclampsia; none had abnormal alpha-hCG levels before onset of preeclampsia. Patients with preeclampsia (21-30 weeks' gestation) demonstrated a mean alpha-hCG level greater than that of normotensive controls but this was not statistically significant. Between 31 and 40 weeks' gestation, mean alpha-hCG levels in the hypertensive and control groups were 210.8 ng/ml and 115.8 ng/ml, respectively (P < 0.001). A stronger association was observed between alpha-hCG and preeclampsia with increasing gestational age (relative risk [RR] 2.07, 21-30 weeks; RR 3.02, 31-40 weeks) and severity (RR 4.51, mild; RR 12.15, severe; RR 16.88, eclampsia). CONCLUSION: There is a strong association between alpha-hCG and preeclampsia, nevertheless this test is unsuitable for predicting preeclampsia. 相似文献
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K Bhalla AM Ibrado E Tourkina C Tang ME Mahoney Y Huang 《Canadian Metallurgical Quarterly》1993,7(4):563-568
The present results demonstrate that the exposure of human myeloid leukemia HL-60 and KG-1 cells to clinically achievable concentrations of taxol produced internucleosomal DNA fragmentation of approximately 200 base-pair multiples, and the morphologic changes characteristic of cells undergoing programmed cell death (PCD) or apoptosis. Taxol-induced PCD was associated with a marked inhibition of suspension culture growth and clonogenic survival of HL-60 cells. In addition, taxol treatment decreased BCL-2 oncogene expression, which is known to block PCD. The exposure to taxol moderately decreased c-myc expression, but did not induce c-jun expression--which has been previously noted for a variety of DNA interactive, antileukemic drugs. These findings indicate that taxol may induce leukemic cell death partly by the alternative but gene-directed and active mechanism of PCD. 相似文献
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B Rayet JA Lopez-Guerrero J Rommelaere C Dinsart 《Canadian Metallurgical Quarterly》1998,72(11):8893-8903
The human promonocytic cell line U937 undergoes apoptosis upon treatment with tumor necrosis factor alpha (TNF-alpha). This cell line has previously been shown to be very sensitive to the lytic effect of the autonomous parvovirus H-1. Parvovirus infection leads to the activation of the CPP32 ICE-like cysteine protease which cleaves the enzyme poly(ADP-ribose)polymerase and induces morphologic changes that are characteristic of apoptosis in a way that is similar to TNF-alpha treatment. This effect is also observed when the U937 cells are infected with a recombinant H-1 virus which expresses the nonstructural (NS) proteins but in which the capsid genes are replaced by a reporter gene, indicating that the induction of apoptosis can be assigned to the cytotoxic nonstructural proteins in this cell system. The c-Myc protein, which is overexpressed in U937 cells, is rapidly downregulated during infection, in keeping with a possible role of this product in mediating the apoptotic cell death induced by H-1 virus infection. Interestingly, four clones (designated RU) derived from the U937 cell line and selected for their resistance to H-1 virus (J. A. Lopez-Guerrero et al., Blood 89:1642-1653, 1997) failed to decrease c-Myc expression upon treatment with differentiation agents and also resisted the induction of cell death after TNF-alpha treatment. Our data suggest that the RU clones have developed defense strategies against apoptosis, either by their failure to downregulate c-Myc and/or by activating antiapoptotic factors. 相似文献
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Numerous attempts have made to describe the particular protein pattern of malignant cells by using high resolution two-dimensional polyacrylamide gel electrophoresis (2-D PAGE). The placental hormone human chorionic gonadotropin (hCG) inhibits tumor initiation and progression in experimental animals and has an inhibitory effect on the proliferation of human breast epithelial cells (HBEC) in vitro. The inhibitory effect on the immortalized HBEC MCF-10F is accompanied by the immunocytochemical expression of inhibin alpha and beta subunits by treated cells. With the purpose of clarifying the molecular mechanisms involved in this effect, the pattern of protein synthesis and mRNA were studied by 2-D PAGE in the immortalized HBEC MCF-10F cells treated in vitro 1001U for 24 h. The effect of hCG treatment on the synthesis of MCF-10F cells was monitored by labeling both control and treated cells with [S35]methionine and separation by 2-D PAGE. At least 11 proteins were preferentially synthesized and five specific polypeptides were decreased in hCG treated cells in comparison with controls. The hCG induced at least four new mRNAs which encoded protein in the molecular mass range of 24-72 kDa. It also increased the expression of at least six mRNAs and reduced the expression of least four mRNAs in comparison with control cells. The hCG-treated cells actively synthesized a 33-kDa polypeptide which was not present in control cells. The nature of this hCG-inducible 33 kDa protein elucidated by immunoprecipating [S35]methionine-labeled proteins with antisera directed against rat inhibin subunit alpha and beta b.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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BACKGROUND: Pneumococcal infections are a common cause of morbidity and mortality among elderly people. Protection against pneumococcal infections is mediated by serotype-specific antibodies to capsular polysaccharides. To obtain an estimate of anti-pneumococcal immunity, prevalence and levels of pneumococcal antibodies were studied in an unvaccinated elderly population. METHODS: IgG antibodies to pneumococcal serotypes 3, 6A, and B and to cell wall polysaccharide (C-PS, a common antigen to all pneumococci) were measured by enzyme immuno-assay in 480 subjects aged 64-97 years (206 men, 274 women) who were a random sample (41%) of elderly inhabitants in a semirural community in Finland. RESULTS: An average of 10% of the elderly lacked antibodies to serotypes 3, 6A, and 8, and 62% of the elderly had them in low titres only. Anti-C-PS antibodies were found in 99% of the elderly, and in significantly higher titres than anti-capsular antibodies. Antibody titres to C-PS and to type 6A decreased with age. Elderly women had significantly lower antibody levels than men. Among the men, current smokers had higher antibody titres than non-smokers; in the women, this analysis was not possible because of infrequent history of smoking. The effect of smoking on antibody titres was reversible after cessation of smoking. CONCLUSIONS: A considerable proportion of the elderly lacked protective antibodies to commonly infecting pneumococcal serotypes 3, 6A, and 8. Smoking increased the prevalence and levels of pneumococcal antibodies probably as a consequence of numerous respiratory infections. These observations emphasize the importance of administration of the pneumococcal vaccine among the elderly. 相似文献
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W Malorni R Rivabene MT Santini S Paradisi F Iosi G Donelli 《Canadian Metallurgical Quarterly》1993,336(2):335-339
It has been hypothesized that programmed cell death (PCD), an active cell suicide process occurring in place of necrosis, can be associated with the pathogenesis of acquired immunodeficiency syndrome (AIDS). The entry of human immunodeficiency virus (HIV) into competent cells is mediated by the CD4 molecule present on the surface of certain lymphocyte subpopulations as well as on some cultured cell lines, e.g. U937 myelomonocytic cells. The present paper focuses on some specific aspects of PCD induced by the cytokine tumor necrosis factor (TNF). The results obtained indicate that the exposure of U937 cells to cycloheximide facilitates TNF-mediated PCD via a short term cell death program and modifies the expression of CD4 surface molecules. This change in surface antigen expression, manifested by internalization of the CD4 molecule, occurs in cells in which apoptosis has been triggered, but not in cells undergoing necrosis. These results indicate that the progression of cell death could be associated with specific alterations of certain surface molecules and could have a role in the entry of HIV into cells. 相似文献