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61.
Jerome Seidenfeld Katherine A. Komar Marisa F. Naujokas Adrienne L. Block 《Cancer chemotherapy and pharmacology》1986,17(1):16-20
Summary We investigated the effect of pretreatment with difluoromethylornithine (DFMO), an ornithine decarboxylase inhibitor, on the cytocidal responses of four human adenocarcinoma cell lines to two alkylating and crosslinking agents: chlorambucil and N,N,N-triethylenethio-phosphoramide (thiotepa). The cell lines studied included HuTu-80 (duodenum), HT-29 (colon), ME-180 (cervix), and A-427 (lung). A 48- to 72-h pretreatment with DFMO reduced intracellular putrescine and spermidine contents to <10% and <1% of control levels. This treatment also caused a 30%–70% decline in spermine content. Survival of control and DFMO-pretreated cells after treatment with chlorambucil or thiotepa was measured by a plating efficiency assy. For three of the four lines studied, the DFMO-induced partial polyamine depletion significantly protected cells from the lethal effects of chlorambucil. In ME-180 cultures alone, DFMO pretreatment did not alter the cytocidal efficacy of chlorambucil. Addition of exogenous putrescine to cultures of HuTu-80, HT-29, or A-427 24 h after DFMO addition but 24 h before treatment with chlorambucil reversed the polyamine depletion and its protective effects on chlorambucil-induced cell kill. In contrast to the above observations, DFMO and partial polyamine depletion had no effect on cell survival after thiotepa treatment for any of the cell lines investigated.Abbreviations BCNU
1,3-bis (2-chloroethyl)-1-nitrosourea
- CENU
chloroethylnitrosourea
-
cis-Pt (II)
cis-diamminedichloroplatinum (II)
- DFMO
difluoromethylornithine
- ODC
ornithine decarboxylase
- PU
putrescine
- SD
spermidine
- SP
spermine thiotepa
-
N,N,N
triethylenethiophosphoramide
This investigation was supported in part by PHS grant no. CA-32758 awarded by the National Cancer Institute, DHHS; by grant no. 82-6 from the American Cancer Society, Ill. Div., Inc.; and by a Biomedical Research Support Grant to Northwestern University Medical School from the US PHS, NIH (RR-05370) 相似文献
62.
Rosby Lucy V. Schmidt Henk G. Tan Gerald J. S. Low-Beer Naomi Mamede Silvia Zwaan Laura Rotgans Jerome I. 《Advances in health sciences education : theory and practice》2021,26(3):1059-1074
Advances in Health Sciences Education - It was recently shown that novice medical students could be trained to demonstrate the speed-to-diagnosis and diagnostic accuracy typical of System-1-type... 相似文献
63.
Julien Guihaire Serena D'Avino Francois Stephan Martin Kloeckner Ngoc Tram To Agathe Potier Maïra Gaillard Ramzi Ramadan Jean‐Luc Taupin Jerome Le Pavec Philippe Deleuze 《Clinical transplantation》2021,35(1):e14146
Antihuman leukocyte antigen (HLA) antibodies restrict the access to cardiac allografts. Desensitization therapy is a major challenge in patients with cardiogenic shock waiting for urgent heart transplantation (HT). We retrospectively reviewed six patients (mean age of 37.5 years [16–70]) who underwent plasmapheresis (PP) under extracorporeal membrane oxygenation (ECMO) before transplant between January 2017 and September 2018. The average duration of follow‐up was 25 months [20–32]. Mean fluorescence intensity (MFI) of HLA‐specific antibodies was reported as follows: score 4 for MFI < 1000, score 6 for 1000 < MFI < 3000 and score 8 for MFI > 3000. The mean duration of ECMO support was 29 days [1–74] and 6.8 [1–29] PP sessions were performed per patient before transplant. The mean number of HLA‐specific antibodies before HT was 9.6 for score 6 [4–13] and 5.8 for score 8 [1–12]. Four patients had major complications after transplantation (2 hemorrhagic shocks, 5 infectious events). Mean MFI reduction rate was 94% [79–100] for Class I and 44.2% for Class II [0–83]. Hospital survival was 100%, and early antibody‐mediated rejection was diagnosed in one patient at 7 days after HT. Plasmapheresis under ECMO support was associated with favorable early outcomes in highly sensitized candidates for urgent heart transplantation. 相似文献
64.
65.
Journal of Digital Imaging - In the human body, cancer is caused by aberrant cell proliferation. Brain tumors are created when cells in the human brain proliferate out of control. Brain tumors... 相似文献
66.
The purpose of this case report is to describe the events, intervention, and aetiology which led to acute airway obstruction in an adult patient after the placement of a Hickman catheter. Airway obstruction secondary to superior vena cava obstruction occurred after placement of a subclavian vein Hickman catheter. This was felt to occur, in part, to a narrowed superior vena cava as evident by subclavian venography. It resulted in emergency oral tracheal intubation to relieve airway obstruction. Shortly after removal of the Hickman catheter, the signs of superior vena cava obstruction syndrome resolved and the patient was extubated without incidence. It is concluded that, although rare, the serious complication of acute airway obstruction can occur after placement of a Hickman catheter. 相似文献
67.
Summary Adriamycin (Adr), the single most active agent used in the treatment of breast cancer, may become ineffective as treatment progresses due to the development of multidrug resistant (MDR) tumors. A major mechanism associated with MDR is increased P-glycoprotein (Pgp) expression. This study examined the abilities of the anti-estrogen tamoxifen (TAM) and the progestin medroxyprogesterone acetate (MPA) as well as cyclosporin A (CsA), a known resistance modifier, to enhance the cytotoxic effects of Adr on human breast epithelial cells (HBEC) in primary culture. Pgp and estrogen receptor (ER) expression were determined in each of the cultures by immunocytochemical assays using the monoclonal antibodies C219 and H222 Sp, respectively. The Adr-sensitive, Pgp-, ER+ MCF-7 cell line and the Adr-resistant, Pgp+, ER-MCF7-AdrR cell line were used as controls. Primary cultures were categorized as HBEC from tissues with or without previous chemotherapy. Pgp was detected in 1 of the 15 cell cultures from tissues without previous chemotherapy and in 5 of the 6 cell cultures from tissues previously exposed to chemotherapy. Incubation with either CsA or MPA plus Adr enhanced Adr toxicity in Pgp+ but not Pgp- cell cultures, whereas TAM had no effect on the sensitivity of any of the cultures. Of the 21 primary cultures of HBEC, 3 were ER+. There was no correlation between the enhancement of Adr cytotoxicity and ER status. The data suggest that MPA as well as CsA may be useful as modifying agents in overcoming Pgp-associated multidrug resistance. 相似文献
68.
Hypertension in the elderly: Age- and disease-related complications and therapeutic implications 总被引:1,自引:0,他引:1
Edward G. Lakatta MD Jerome D. Cohen Jerome L. Fleg Edward D. Frohlich Alan H. Gradman 《Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy》1993,7(4):643-653
Summary Effective treatment of hypertension in the elderly requires an understanding of both the progressive course of the disease and the impact of aging on the cardiovascular system, including physiological, genetic, lifestyle, and environmental factors. Review of the literature that has attempted to define the impact of an aging process on cardiovascular structure and function reveals a diversity of findings and interpretations. However, in general, normotensive elderly subjects exhibit the heart and vascular characteristics of muted hypertension, including many features of younger hypertensive patients: cardiac hypertrophy, diminution in resting left ventricular early diastolic filling rate, increased arterial stiffness and aortic impedance, diminution in the baroreceptor reflex, a diminished response to catecholamines and diminished renal blood flow, and an increase in peripheral vascular resistance (PVR). Treatment of elderly hypertensives is more challenging because of the greater likelihood of the presence of concomitant diseases, most importantly, coronary and peripheral atherosclerosis, renal dysfunction, and diabetes mellitus. Isolated systolic hypertension (ISH), the most common form of hypertension in the elderly, has also been clearly shown to be an important predictor of cardiovascular morbidity and mortality, including coronary artery disease, congestive heart failure, and stroke. Treatment of ISH has been shown to lower systolic pressure safely and effectively in the elderly. By reducing PVR, and possibly the arterial stiffness, and thus the early reflected pulse waves, vasodilators, including calcium antagonists, may lower these three components of arterial impedance, and hence lower the arterial load on the heart. The cardiac hypertrophy and reduced left ventricular filling rate associated with hypertension in older individuals can also be ameliorated, to some extent, by calcium channel blockers.Proceedings of a symposium held in Atlanta, Georgia on March 2, 1991. 相似文献
69.
Dennis J. Munjack M.D. L. Jerome Oziel Ph.D. Pamela H. Kanno B.A. Katherine Whipple Ph.D. Michele D. Leonard 《Archives of sexual behavior》1981,10(2):123-131
This study was designed to obtain objective data on the personality profiles of two groups of males with a primary complaint of erectile failure and compare them to a group of psychiatric patients unselected for sexual dysfunction and to a sexually normal control group. Utilizing the Eysenck Personality Inventory, the Institute of Personality and Ability Testing Anxiety Scale, Symptom Checklist, and the Minnesota Multiphasic Personality Inventory, it was determined that males applying to a university/county hospital sex-dysfunction clinic appeared similar to patients seen in the same clinic who were unselected for sex dysfunction and more psychologically disturbed than patients with the same complaint applying for treatment at a private clinic. All three groups showed more psychopathology than sexually normal males. The implications of these findings are discussed. 相似文献
70.
Simple randomization of patients to treatment regimens in clinical trials can result in inbalance among stratum categories. Procedures that produce balance may lack randomness. Systems that are not deterministic yet produce balance are often extremely complex and are not easily performed by randomization clerks. A microcomputer-based voice-response system has been implemented that permits clinic staff to easily randomize patients in clinical trials despite the complexity of the algorithm. Data entry is accomplished by the use of Touch-Tone keys. Input prompts and regimen assignment are spoken by a commercially available voice synthesizer. 相似文献