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C Belloir

Publications and source records attributed to C Belloir.

17 recordsLinked to original sources
PubMed2006

Protective effects of garlic sulfur compounds against DNA damage induced by direct- and indirect-acting genotoxic agents in HepG2 cells.

The aim of this study was to assess the antigenotoxic activity of several garlic organosulfur compounds (OSC) in the human hepatoma cell line HepG2, using comet assay. The OSC selected were allicin (DADSO), diallyl sulfide (DAS), diallyl disulfide (DADS), S-allyl cysteine (SAC) and allyl mercaptan (AM). To explore their potential mechanisms of action, two approaches were performed: (i) a pre-treatment protocol which allowed study of the possible modulation of drug metabolism enzymes by OSC before treatment of the cells with the genotoxic agent; (ii) a co-treatment protocol by which the ability of OSC to scavenge direct-acting compounds was assessed. Preliminary studies showed that, over the concentration range tested (5-100 microM), the studied OSC neither affected cell viability nor induced DNA damage by themselves. In the pre-treatment protocol, aflatoxin B1 genotoxicity was significantly reduced by all the OSC tested except AM. DADS was the most efficient OSC in reducing benzo(a)pyrene genotoxicity. SAC and AM significantly decreased DNA breaks in HepG2 cells treated with dimethylnitrosamine. Additionally, all the OSC studied were shown to decrease the genotoxicity of the direct-acting compounds, hydrogen peroxide and methyl methanesulfonate. This study demonstrated that garlic OSC displayed antigenotoxic activity in human metabolically competent cells.

Aflatoxin B1↗
PubMed2001

Antimutagenic activity of organosulfur compounds from Allium is associated with phase II enzyme induction.

In a previous study, we showed that naturally occurring organosulfur compounds (OSCs) from garlic and onion modulated the activation of carcinogen via the alteration of cytochromes P450. The present study was undertaken to determine the incidence of the in vivo induction of phase II enzymes by individual OSCs on the genotoxicity of several carcinogens. Diallyl sulfide (DAS), diallyl disulfide (DADS), dipropyl sulfide (DPS) and dipropyl disulfide (DPDS), were administered by gavage (1mmol/kg) to male SPF Wistar rats for 4 consecutive days. The effects of treatments on phase II enzymes and on the genotoxicity of carcinogens were evaluated with hepatic cytosols and microsomes from OSCs-treated rats. DADS strongly increased all the phase II enzymes activities examined, i.e. total glutathione S-transferase (GST) activity, mu GST activity, quinone reductase (QR) activity and epoxide hydrolase (EH) activity. In addition, DADS strongly increased the protein level of rGSTP1. QR activity, total and mu GST activities were also increased by DAS and DPDS whereas DPS increased only mu GST activity and QR activity. To assess the repercussions of these inductions on the genotoxicity of carcinogens, the effects of cytosols or microsomes from OSCs-treated rats on the mutagenicity of (+)-anti-7beta,8alpha-dihydroxy-9alpha,10alpha-oxy-7,8,9,10-tetrahydrobenzo[a]pyrene (BPDE), styrene oxide (SO) and 4-nitroquinoline 1-oxide (4-NQO) were measured in the Ames test. DADS showed a very effective antimutagenic activity against BPDE, SO and 4-NQO. DAS reduced the mutagenicity of BPDE and SO. In contrast, DPS and DPDS showed little efficient antimutagenic activity since they only reduced the mutagenicity of BPDE and 4-NQO, respectively. Interestingly, DADS appeared to be as effective as ethoxyquin, a model inducer of phase II enzymes, in both inducing phase II enzymes and inhibiting the mutagenicity of carcinogens. This study demonstrated that the antimutagenic activities of OSCs against several ultimate carcinogens were closely related to their ability to induce phase II enzymes.

Administration, Oral↗
PubMed2000

Liver subcellular fractions from rats treated by organosulfur compounds from Allium modulate mutagen activation.

The effects of in vivo administration of naturally occurring organosulfur compounds (OSCs) from Allium species were studied on the activation of several mutagens. Male SPF Wistar rats were given p.o. one of either diallyl sulfide (DAS), diallyl disulfide (DADS), dipropyl sulfide (DPS) or dipropyl disulfide (DPDS) during 4 consecutive days and the ability of hepatic S9 and microsomes from treated rats to activate benzo[a]pyrene (BaP), cyclophosphamide (CP), dimethylnitrosamine (DMN), N-nitrosopiperidine (N-PiP) and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) was determined in the Ames test. Administration of DAS, DPS and DPDS resulted in a significant increase of the activation of BaP, CP, N-PiP and PhIP mediated by S9 and microsomes while DADS treatment only increased the mutagenicity of PhIP. In contrast, S9 from DADS-treated rats significantly inhibited the mutagenicity of N-PiP and BaP. DAS, DADS and DPS strongly inhibited DMN mutagenicity while DPDS enhanced it. To understand the mechanisms underlying these effects, the modifications of the activities of specific isozymes of CYP involved in the activation of these mutagens were studied. DAS, DPS and DPDS strongly enhanced pentoxyresorufin O-dealkylase (PROD) activity related to CYP2B and slightly increased ethoxyresorufin O-deethylase (EROD) and methoxyresorufin O-demethylase (MROD) activities related to CYP1A family. DADS exerted the same effects than other OSCs but to a lesser extent. p-Nitrophenol hydroxylase (PNPH) activity related to CYP2E1 was inhibited by DAS and DADS, whereas DPDS significantly increased this activity. Hence, the effects of OSCs on the mutagenicity of several genotoxic compounds are mediated by modification (enhancement or inhibition) of specific CYP involved in their activation.

Allium↗
PubMed1988

Desmoid tumors in adults: the role of radiotherapy in their management.

Twenty-six adult patients with the pathologic diagnosis of desmoid tumor were treated between 1964 and 1983 at the Institut Curie in Paris with megavoltage irradiation. Twenty of these patients (76 percent) had extraabdominal tumors. Definitive surgical resection was performed on nine patients (one received preoperative radiotherapy). At last follow-up 1 1/2 to 10 years after treatment, all of the patients had no evidence of disease. Seven of the nine had follow-up examinations from 5 to 10 years after treatment. Seven patients had postoperative radiotherapy with doses from 4,700 to 6,500 rads (47 to 65 Gy) for either microscopic (three patients) or gross (four patients) residual disease. All but one patient had no evidence of disease from 2 to 8 years after treatment. Nine patients had radiotherapy for recurrent inoperable tumors and six had no evidence of disease from 3 to 20 years after treatment. Recurrences developed in three patients; outside the treatment portal in one, and the other two had received less than 5,000 rads (50 Gy). Clinical regression of tumors after treatment was slow, with complete regression taking up to 2 years. Postoperative radiotherapy with doses of at least 5,000 to 6,000 rads (50 to 60 Gy) was effective in achieving local control of inoperable or incompletely resected tumors, thus the need for repeated resections was avoided. Computerized tomography has greatly improved the assessment of tumor extension and should be used routinely before either operation or radiotherapy to obtain adequate margins and minimize the chance of missing disease.

Adolescent↗
PubMed1986

[Radiologic surveillance of irradiated glomal tumors].

A favorable clinical result was obtained in 10 patients with jugular glomal tumors treated by external radiotherapy (approximately 50 Gy), alone or combined with surgical treatment, and preceded in some cases by embolization. Radiologic review examinations showed complete stability of lesions without bone reconstruction phenomena, in spite of a decrease in tympanic mass and regression of functional symptoms.

Adult↗
PubMed1985

[Metastases of breast angiosarcoma. Apropos of 2 cases].

Two patients with breast angiosarcoma and hepatic and splenic metastases developed a hemoperitoneum confirmed by ultrasound and CT scan imaging. This complication has further adverse effects on the already extremely poor prognosis of this disease.

Adult↗
PubMed1981

[Contribution of scanning to the diagnosis and evaluation of acquired anomalies of the aorta (author's transl)].

Acquired anomalies of the aorta represent at the present time an excellent indication for scanning in vascular diseases. This form of examination permits perfect visualization of aneurysms, wherever they are located, frequently enabling a tumour in the vicinity of the aorta to be eliminated. It provides an exact topographic picture of the lesions with a quantitative indication of their height. The detection of a peri-aortic hematoma facilitates the diagnosis of cracking of the aneurysm. Scanning has a far from negligible contribution to make to the diagnosis of aortic dissections. The visualization of intraluminal calcifications at a distance from the wall, of a floating membrane or a false channel provides confirmation of the diagnosis and suggests the possibility of an angiography. As an additional bonus in the case of acute ischaemia of the lower limbs, scanning permits an easy and inexpensive diagnosis of a complete thrombosis of the aorta and an indication of its extent. Computerised scanning as a non-invasive and easily repeated examination, has numerous and widely varying indications in the pathology of the aorta. Its potential contribution in certain cases appears to be so great as to envisage its delaying angiography.

Aneurysm↗
PubMed1980

Computed tomography diagnosis of renal angiomyolipoma.

Six computed tomography examinations were performed on four patients: two of them had tuberous sclerosis, and the other two had solitary angiomyolipomas. Computed tomography is an easy way of diagnosing tumoral hemorrhages and thus facilitates the supervision of patients with tuberous sclerosis. In two patients, the authors observed dense masses that might have indicated cartilage deposits.

Adult↗
PubMed1980

Computed tomography of aortic dissection.

Fourteen patients suspected of having dissection of the thoracic aorta, two with possible extensions into the abdomen of previously diagnosed dissection of the thoracic aorta, and one patient who had undergone surgical repair of an aortic dissection were examined by CT (computed tomography). Findings included localized increase of the aortic caliber, displaced intimal calcifications, intimal flaps, and false channels. These findings were confirmed by angiography or at necropsy. Two patients in whom CT showed no abnormalities had a favorable outcome. The authors conclude that CT is the examination of choice in removing doubt from the clinical diagnosis of aortic dissection.

Aortic Dissection↗
PubMed1979

[Aortocoronary bypass permeability explored by tomodensitometry. Preliminary study].

The patency of 24 aorto-coronary grafts was studied by tomodensitometry. --16 out of the 18 bypasses examined within the two weeks following surgery were seen. --4 older bypasses were not visible, either by scanner or by angiography and were therefore occluded: two more, performed more than a year previously, were patent on tomodensitometric examination. The interpretation of the results, discussed taking into account the small number of angiographic check ups does not permit any formal conclusion as to the validity of the procedure. The results of this technique seem satisfactory and quite comparable with other non invasive methods used in the study of aorto-coronary grafts.

Adult↗
PubMedDate not supplied

[Contribution of computed tomography to the exploration of congenital anomalies of the inferior vena cava. A report on five cases (author's transl)].

3 cases of abnormalities of the inferior vena cava are reported: one isolated left inferior vena cava, one duplication of the inferior vena cava with continuation by a left inferior hemi-azygos vein and a simple duplication of the post-renal inferior vena cava. Finally, 2 cases of retro-aortic left renal vein are described. These abnormalities may be fully studied by computed tomography which in certain cases makes it possible to avoid inferior cavography. The authors emphasize potential sources of error in interpretation and the value of being aware of the congenital malformation of the inferior vena cava.

Female↗
PubMedDate not supplied

[Value of computed tomography for the investigation and diagnosis of aortic aneurysms (author's transl)].

Abdominal or thoracic aneurysms can be perfectly well visualized by computed tomography, and tumors lying close to the aorta and simulating ectasia can often be eliminated. The exact topographical features of the lesions can be defined as well as their extension superiorly. In many cases, calcifications, clots, a permeable channel, or even a periaortic hematoma showing fissuration can be demonstrated. On many occasions the value of computed tomography is such that angiography may not be necessary.

Adult↗