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41.
Phenobarbital and clofibrate, two non-genotoxic carcinogens, have been
investigated regarding the relationship between reactive oxygen species,
antioxidant enzyme expression and apoptosis in primary cultures of rat
hepatocytes. Low toxicity concentrations, 200 and 100 microg/ml for
phenobarbital and clofibrate respectively, were used to examine their
effect on spontaneous or transforming growth factor beta1
(TGFbeta1)-induced apoptosis and on the expression of antioxidant defence
enzymes (superoxide dismutases and catalase). The increased incidence of
apoptotic nuclei was visualized in TGFbeta1-treated cultures with the
fluorescent dye Hoechst 33258 and was quantified under all experimental
conditions by measurement of the hypodiploid peak in DNA histograms
obtained by flow cytometry. Both substances, when added separately to
hepatocyte cultures and incubated for 24 and 48 h, significantly diminished
spontaneous apoptosis and exhibited a slight suppression of
TGFbeta1-induced apoptosis. Endogenous peroxide production by hepatocytes
increased with TGFbeta1, phenobarbital or clofibrate and the increase was
greater with phenobarbital and in the presence of TGFbeta1 with both drugs.
Gene expression of catalase and Mn- and Cu,Zn superoxide dismutases (SOD)
was evaluated by northern blot analysis of hepatocytes incubated in the
presence of phenobarbital or clofibrate with or without TGFbeta1 and the
following differences were detected: phenobarbital induced a significant
decrease in both dismutases (to 56%, P < 0.05, and 55%, P < 0.05, for
Mn- and Cu,Zn-SOD respectively) and a 2-fold increase (P < 0.01) in
catalase; clofibrate induced a slight decrease in both SODs and a 4-fold
increase (P < 0.05) in catalase; TGFbeta1 significantly decreased to 37%
(P < 0.05) expression of catalase while not significantly affecting
expression of both SODs. We conclude that inhibition of spontaneous
apoptosis induced by either phenobarbital or clofibrate is accompanied by
increases in the endogenous levels of peroxides and by significant
induction of catalase gene expression. Furthermore, the lack of effect of
both compounds on TGFbeta1-induced apoptosis could be a consequence of the
inability of these two compounds to counteract the depressing effect of
TGFbeta1 on expression of catalase.
相似文献
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AM Halefoglu 《Journal of Medical Imaging and Radiation Oncology》2005,49(3):242-245
A pulmonary arteriovenous fistula is an abnormal connection between pulmonary arteries and veins. Patients with Rendu–Osler–Weber syndrome may present with this vascular malformation, which is a typical finding of the disease. Approximately 5–15% of Rendu–Osler–Weber syndrome patients have pulmonary arteriovenous malformations (AVM) and there is usually a family history of AVM in these patients. The malformations are usually located in the lower lobes. In this paper, I describe a 49‐year‐old male patient with dyspnoea, cough, haemoptysis and epistaxis. Physical examination showed nasal telangiectasias, cyanosis of the lips and nails, and a systolic bruit over the left lung. Chest X‐ray revealed a 5‐cm mass in the left lower lobe and after magnetic resonance examination, together with 3‐D magnetic resonance angiography, it was demonstrated to be a pulmonary arteriovenous fistula. The history of a niece with a similiar history of suspected pulmonary arteriovenous fistula led me to consider the possibility of Rendu–Osler–Weber syndrome presenting with a pulmonary arteriovenous fistula. 相似文献
45.
Infante AF Albert MC Jennings WB Lehner JT 《Clinical orthopaedics and related research》2000,(376):106-112
Immediate closed reduction and application of a well-molded hip spica cast is a safe and effective treatment option for closed, isolated femur fractures in children who weigh between 10 and 100 pounds. Between 1988 and 1996, 190 immediate hip spica casts were placed on children with isolated femoral shaft fractures who weight between 10 and 100 pounds. Fifteen patients were lost to followup leaving 175 children who were evaluated and followed up for at least 2 years after the hip spica cast was removed (range 2-10 years). The femur fractures were reduced closed and placed in a 1 1/2 hip spica cast in the emergency room with the patient under conscious sedation or in the operating room with the patient under general anesthesia. All of the children returned home within 24 hours of the procedure. All 175 femur fractures united within 8 weeks. The only complication was a refracture in a 25 pound child who fell 1 week after the cast was removed. No significant residual angular deformities were present in any of the children at last followup. None of the children required external shoe lifts, epiphysiodesis, antibiotics, irrigation and debridements, or limb lengthening procedures for leg length inequalities. The authors think that immediate closed reduction and placement of a well-molded hip spica cast is a safe and reliable treatment option for isolated, closed femur fractures in children from birth to 10 years of age who weigh less than 80 pounds. 相似文献
46.
F Ballet J Robert M E Bouma P Vrignaud R Infante 《Pharmacological research communications》1986,18(4):343-347
Epirubicin is the only anthracycline to be metabolized in humans through a glucuronidation pathway which is not observed in laboratory animals. In search of a model for the experimental study of this metabolism, we have observed that human hepatocytes in culture exhibited this pathway and could be of interest for the understanding of the metabolism of this new drug. 相似文献
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Molina Infante J Núñez Martínez O Nogales Rincón O Ponferrada Díaz A Borrego Rodríguez GM 《Anales de medicina interna (Madrid, Spain : 1984)》2003,20(8):413-415
The presence of acute fluid collections is an habitual event in an acute pancreatitis, generally followed by a favourable outcome. We present a case about an ancient woman suffering from an acute necrotizing pancreatitis with tense fluid collections that produced espontaneously several cutaneous fistula. We find no report on literature about this uncommon complication. We revised clinical management of acute fluid collections and pancreatic fistulas. 相似文献
50.
Jacqueline AM Smith DL Patil OT Daniels Y-S Ding J-D Gallezot S Henry KHS Kim S Kshirsagar WJ Martin GP Obedencio E Stangeland PR Tsuruda W Williams RE Carson ST Patil 《The international journal of neuropsychopharmacology / official scientific journal of the Collegium Internationale Neuropsychopharmacologicum (CINP)》2015,18(2)