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G Benoit

Publications and source records attributed to G Benoit.

At least 19 recordsLinked to original sources

Study of kidney and liver viability in the rat after exclusive aortic perfusion using intracellular ATP measurement.

To find whether the liver can be procured after exclusive aortic perfusion, three organ perfusion models were used in three groups of donor rats. Group 1 underwent liver wash-out via the portal vein; in group 2, the kidneys alone were perfused via the aorta; and group 3 underwent simultaneous aortic perfusion of liver and kidneys. All perfusion flow rates in the three groups were adjusted to physiological values. Harvested organs were transplanted and recipient animals were killed 4 h after transplantation to study liver and kidney viability by using intracellular ATP measurement. Liver ATP was lower (P < 0.005) in the portal perfusion group (group 1: 1.396 +/- 0.412) than in the aortic perfusion group (group 3: 2.181 +/- 0.061). Kidney ATP was comparable in groups 2 and 3:1.066 +/- 0.09 vs 1.059 +/- 0.273 (mumol/g) tissue). Liver cooling was quicker with portal perfusion than with the aortic flush (20 degrees C in 20 s vs 15 degrees C in 60 s). Aortic perfusion at a physiologic flow rate has no detrimental effect on renal viability studied by intracellular ATP measurement. We conclude that liver cooling via the aortic route only is a good alternative to portal perfusion and seems to give good preservation. Application of this observation to emergency procurement in humans is still the subject of controversy.

Adenosine Triphosphate

Evidence that antihuman tumor necrosis factor monoclonal antibody prevents OKT3-induced acute syndrome.

We have used an antihuman tumor necrosis factor monoclonal antibody, CB006 (murine IgG1), to prevent the OKT3-induced acute clinical syndrome. This syndrome is due to the massive, although transient release in the circulation of various cytokines (TNF, interferon gamma, interleukin 2, interleukin 6) and represents one important side effect linked to in vivo use of OKT3. Fourteen kidney allograft recipients undergoing prophylactic OKT3 therapy were treated with CB006 in a single i.v. injection of either 0.4 mg/kg (group I, 7 patients) or 2 mg/kg (group II, 7 patients), 1 hr before the first OKT3 administration. Nineteen consecutive patients formed a historical control group. None of the CB006-pretreated patients showed any of the common, severe OKT3-associated symptoms (hypotension, respiratory distress, or neurotoxicity), which were observed in 10% of the historical controls. In addition, CB006-treated patients showed a lower frequency of pyrexia (> or = 39 degrees C) and gastrointestinal symptoms. None of the CB006-treated patients presented severe vomiting or diarrhea, defined as repeated episodes inducing significant fluid and electrolyte loss. Two out of the 7 patients in group I and group II had mild transitory diarrhea. Mild single vomiting episodes occurred in 2 group I patients and 3 group II patients. At variance in all controls, gastrointestinal symptoms were long lasting and associated with major prostration due to electrolyte and fluid loss. Importantly, CB006-treated patients who presented mild symptoms had detectable bioactive circulating TNF, showing incomplete inactivation of OKT3-induced TNF by CB006. CB006 was perfectly well tolerated, did not induce xenosensitization, and did not affect the biological or clinical effectiveness of OKT3.

Acute Disease

Anti-HLA antibodies depletion on protein A-sepharose columns in hyperimmunized patients awaiting renal transplantation.

To reduce anti-HLA immunization, 15 patients waiting for a renal graft received the following treatment: 5 to 7 immunoadsorption sessions on protein A-Sepharose columns, immunosuppressive drugs (corticosteroids 1 mg/kg (bw/day+cyclophosphamide 2 mg/kg bw/day) and iv polyclonal immunoglobulins. Before this treatment, panel-reactive antibodies ranged from 65 to 100% and antibody titers varied from 1/8 to 1/128. In all patients, antibody, titers were decreased. However, antibody resynthesis was incompletely blocked by this protocol. Eight out of 12 grafted patients had a functional kidney transplant 3 months to 3 years post-grafting. There early kidney failures occurred in the subgroup of 5 patients who had had historical positive cross matches prior to treatment. This treatment did not seem to increase the frequency of infectious complications before or after grafting.

Adult

[Quantification of nucleolar organizers (NORs) in renal carcinomas. Comparison with the nuclear grade].

Twenty three renal tumours: 6 clear cell carcinomas, 3 granular cell carcinomas, 8 mixed cell carcinomas, 3 tubulopapillary tumours, 2 spindle cell carcinomas and 1 oncocytoma, were retrospectively submitted to a staining technique which reveals argyrophilic proteins related to Nucleolar Organizer Regions (NORs). The semiautomated quantification of the number and mean surface area of the argyrophilic granules was performed by means of a quantimeter. The results were compared to the nuclear grade, which constitutes the reference histological prognostic factor. A very good correlation was observed between NORs and nuclear grade. The mean number of argyrophilic granules per nucleus (n) and more particularly their surface area (s) were very significantly increased in high-grade carcinomas (n = 1.96), s = 3.72) in comparison with low-grade carcinomas (n = 1.50, s = 1.35). Quantification of NORs therefore allowed objective differentiation between a low nuclear grade and a high nuclear grade. The quantification method used emphasised the value of not only measuring the number but also the surface area of the argyrophilic granules.

Cell Nucleus

[Vesico-sphincteric disorders in patients with Parkinson's disease].

Vesicosphincteric disorders are frequent in patients with Parkinson's disease, due to a lesion of the locus niger of the extrapyramidal tract which no longer secretes sufficient dopamine to activate the nigrostriatal tract. The commonest symptoms are urgent micturition, dysuria or a combination of the two. 50% of patients with Parkinson's disease present with disturbances of micturition and these symptoms may be presenting complaint of the disease in 10% of cases. Cystomanometry reveals detrusor hyperactivity in more than 60% of cases and hypoactivity in less than 30% of case, while dyssynergia is less common. Delayed relaxation of the striated sphincter may sometimes be observed. Urological problems must therefore be distinguished from urological problems in these patients. A combined urological and urodynamic assessment is essential as the risk of incontinence following prostate surgery is 20%. Stress urinary incontinence in women may mask or be associated with urgency. These vesicosphincteric disorders must therefore be treated cautiously with a combination of medical treatment (dopatherapy increases detrusor control), retraining and occasionally surgery after a detailed urodynamic assessment.

Female

Decrease in renal vascular resistance in University of Wisconsin solution preserved kidney transplants.

Renal vascular resistance was compared in 2 groups of renal grafts: group 1-16 kidneys perfused with University of Wisconsin solution and group 2-16 kidneys perfused with Euro-Collins solution. Both groups had comparable donors and recipient criteria. Renal blood flow was measured by a miniaturized pulsed Doppler probe fixed on the graft renal artery. Renal vascular resistance was calculated either according to the formula: renal vascular resistance (mm. Hg/ml. per second) = systemic arterial pressure (P)/renal blood flow or through the renal vascular resistive index (RVRI): RVRI = systolic flow velocity - diastolic flow velocity/systolic flow velocity = (S-D)/S. Renal vascular resistance estimation seems to be more contributory than renal blood flow in assessment of renal graft reperfusion disorders. Our results show that University of Wisconsin solution seems to preserve intrarenal arterial caliber better with a decrease in intrarenal vascular resistance, thus, allowing for a higher arterial graft perfusion flow.

Adenosine

[Histologic identification of the afferent fibers of the pelvic plexus].

The inferior hypogastric (pelvic) plexus conveys two types of fibres: sympathetic fibres originating in the thoracolumbar sympathetic chain and parasympathetic fibers originating in the sacral anterior rami. By using a histofluorescent stain (glyoxalic acid) and a histochemical stain (thiocholine) in 17 fresh cadavres, we have demonstrated that the sympathetic fibres arise from sacral sympathetic ganglia. These fibres participate in the constitution of the pelvic splanchnic nerves. In this study, we confirm that the inferior roots of the pelvic plexus are not only parasympathetic, but also sympathetic.

Adrenergic Fibers