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The Eurotransplant Senior Program (ESP) has expedited the chance for elderly patients with kidney failure to receive a timely transplant. This current study evaluated survival parameters of kidneys donated after brain death with or without matching for HLA-DR antigens. This cohort study evaluated the period within ESP with paired allocation of 675 kidneys from donors 65 years and older to transplant candidates 65 years and older, the first kidney to 341 patients within the Eurotransplant Senior DR-compatible Program and 334 contralateral kidneys without (ESP) HLA-DR antigen matching. We used Kaplan-Meier estimates and competing risk analysis to assess all cause mortality and kidney graft failure, respectively. The log-rank test and Cox proportional hazards regression were used for comparisons. Within ESP, matching for HLA-DR antigens was associated with a significantly lower five-year risk of mortality (hazard ratio 0.71; 95% confidence interval 0.53-0.95) and significantly lower cause-specific hazards for kidney graft failure and return to dialysis at one year (0.55; 0.35-0.87) and five years (0.73; 0.53-0.99) post-transplant. Allocation based on HLA-DR matching resulted in longer cold ischemia (mean difference 1.00 hours; 95% confidence interval: 0.32-1.68) and kidney offers with a significantly shorter median dialysis vintage of 2.4 versus 4.1 yrs. in ESP without matching. Thus, our allocation based on HLA-DR matching improved five-year patient and kidney allograft survival. Hence, our paired allocation study suggests a superior outcome of HLA-DR matching in the context of old-for-old kidney transplantation.

This study investigates which forebrain structures show Fos protein expression during conditioned taste aversion (CTA) acquisition and whether Fos expression depends on the aversion strength. A novel taste paired with an intraperitoneal injection of a low dose of the malaise-inducing agent lithium chloride (LiCl) induced a weak CTA, whereas associating this novel taste with a high dose of LiCl induced a strong CTA. Increasing the strength of the gastric malaise alone enhanced Fos expression in central, basal, and lateral amygdala nuclei and decreased Fos expression in the nucleus accumbens core. Taste-malaise association induced specific Fos activation in the insular cortex (with both the low and the high doses of LiCl) and the nucleus accumbens shell (with the high LiCl dose only). No significant variation of Fos expression was measured in the perirhinal cortex. Several forebrain areas may be sites of taste-malaise convergence during CTA acquisition depending on the strength of the aversion. Keywords: acquisition, amygdala, accumbens, insular cortex, learning

L'objectif de cette étude était de comparer la sévérité de la maladie COVID-19 chez les patients hospitalisés en Belgique infectés par le variant Delta à ceux infectés par le variant Alpha du SARS-CoV-2.

Les souches de SARS-CoV-2 évoluent continuellement en accumulant des mutations dans leur génome au cours de la pandémie. Nous présentons ici un cadre conceptuel général qui permet d'étudier l'effet des variants du SARS-CoV-2 sur la sévérité de la maladie COVID-19.

Today's industry faces intense pressure to reduce energy consumption and to extend components' lifetimes in order to reduce economic and environmental costs. During the last few years, it has been pointed out that fluid wall slip is likely to improve friction in low-loaded mechanisms; if the slip zone covers only a specific zone of the surface, improvement of both load and friction can be obtained. The physico-chemical heterogeneity of the surface acts as a geometrical discontinuity and induces pressure gradients analogous to those occurring in a Rayleigh step bearing. Such favourable behaviour can be inhibited if the location of the slip/no-slip areas causes cavitation. This article aims to show the importance of the choice of the cavitation model in the analysis of slip/no-slip hydrodynamic contacts. Current practice predicts the performance of cavitated devices by using the well-known Half-Sommerfeld or Swift—Stieber models. However, using a mass-flow conserving model such as the so-called Floberg—Elrod—Adams model can lead to qualitatively and quantitatively different conclusions.The simple case of a parallel slider bearing is of particular interest. If alternating slip/no-slip areas are introduced, then a non-zero load-carrying capacity can be obtained whose theoretical value dramatically depends on the cavitation model and even on the inlet flowrate of the lubricant.

AbstractUp to now, the prognosis of peritoneal carcinomatosis from GI tract cancers remains very poor. Intraperitoneal hyperthermic chemotherapy has been proposed in the prevention or treatment of peritoneal carcinomatosis. The rationale for this locoregional approach comes from a better knowledge of the physiopathology of the disease. Intraperitoneal chemotherapy achieves high local drug concentration with limited systemic toxicity. It should be performed during or immediately after surgery to be effective towards microscopic residual tumor cells. A synergistic cytotoxic effect has been demonstrated when heat is combined with antineoplastic drugs. Intraperitoneal hyperthermic chemotherapy might not be regarded as the panacéebut as a promising step in the management of peritoneal carcino-matosis.Some randomized studies of gastric cancer with macroscopic serosal invasion have suggested the efficacy of hyper-thermic intraperitoneal chemotherapy for the prevention of peritoneal carcinomatosis. In patients with peritoneal carci-nomatosis, some studies suggest, in selected cases, the positive effect of hyperthermic intraperitoneal chemotherapy on survival, when combined with cytoreductive surgery.

Supplemental intra-operative oxygen 80% halves the incidence of nausea and vomiting after open and laparoscopic abdominal surgery, perhaps by ameliorating intestinal ischaemia associated with abdominal surgery. It is unlikely that thyroid surgery compromises intestinal perfusion. We therefore tested the hypothesis that supplemental perioperative oxygen does not reduce the risk of postoperative nausea and vomiting (PONV) after thyroidectomy.

Abstract.Thyrotoxicosis is the clinical syndrome that results when tissues are exposed to high levels of circulating thyroid hormones. In most instances, thyrotoxicosis is due to hyperthyroidism, a term reserved for disorders characterized by overproduction of thyroid hormones by the thyroid gland. Nevertheless, thyrotoxicosis may also result from a variety of conditions other than thyroid hyperfunction. The present report focuses on the etiologies, pathophysiology and treatment of iatrogenic thyrotoxicosis. Iatrogenic thyrotoxicosis may be caused by 1) subacute thyroiditis (a result of lymphocytic infiltration, cellular injury, trauma or radiation) with release of preformed hormones into circulation, 2) excessive ingestion of thyroid hormones (“thyrotoxicosis factitia”), 3) iodine-induced hyperthyroidism (radiological contrast agents, topical antiseptics or other medications). Among these causes of iatrogenic thyrotoxicosis, that induced by the iodine overload and cytotoxicity associated with amiodarone represents a significant challenge. Successful management of amiodarone-induced thyrotoxicosis requires close cooperation between endocrinologists and endocrine surgeons. Surgical treatment may have a leading yet often underestimated role in view of the potential life-threatening severity of this disease, whereas others kinds of iatrogenic thyrotoxicosis are usually treated conservatively.

Recent studies have shown that in certain situations, usually described by mixed lubrication models, a continuous ultra-thin film could separate two solids, even at the scale of asperities. In this paper, the consequences of this assumption are examined in the case of cold rolling geometries. The tribological behaviour is derived from the resolution of the Reynolds equation. The influence of the rheological parameters of the lubricant and of the existence of a cavitation zone is discussed.

Different ways of supplying a liquid film with lubricant initially contained in a porous structure have been investigated experimentally: centrifugation, creeping by roughness or thermal effects. Observations and measurements concerning sintered porous materials (polyimide, stainless steel) impregnated with conventional lubricants for space applications (MAC or PFPE) are presented and discussed in this paper. Centrifugation caused the release of lubricant from the porous structure when a threshold in rotational speed had been reached, proving consistent with an analytical model in which the threshold is a function of oil surface tension and pore radius. We also observed some leakage from porous samples deposited on rough stainless-steel substrates. But the lost volume did not depend on surface roughness. On the other hand, a temperature gradient representative of the temperature distribution in running ball bearings proved unable to make the oil spread out from the tank, although capillary effects due to roughness did.

AbstractHypnosis has become routine practice in our plastic and endocrine surgery services. Revivication of pleasant life experiences has served as the hypnotic substratum in a series of over 1650 patients since 1992. In retrospective studies, followed by randomised prospective studies, we have confirmed the usefullness of hypnosedation (hypnosis in combination with conscious IV sedation) and local anaesthesia as a valuable alternative to traditional anaesthetic techniques.The credibility of hypnotic techniques and their acceptance by the scientific community will depend on independently — confirmed and reproductible criteria of assessing the hypnotic state. Based on the clinical success of this technique, we were interested in confirming this phenomenon in healthy volunteers. The revivication of pleasant life experiences thus served as the cornerstone of a basic research program developed to objectify the neurophysiological attributes of the hypnotic state. We compared hypnosis to normal alertness with similar thought content. In our experience, the activation profile obtained during the hypnotic state was completely different from simple re-memoration of the same subject matter during normal alertness. This represents an objective and independent criteria by which to assess the hypnotic state.

AbstractBetween April 1994 and June 1997, 197 thyroidectomies and 21 cervical explorations for hyperparathyroidism were performed under hypnosedation (HYP) and compared to the operative data and postoperative courses of a closely-matched population (n = 121) of patients operated on under general anaesthesia (GA). Conversion from hypnosis to GA was needed in two cases (1%). All surgeons reported better operating conditions for cervicotomy using HYP. All patients having HYP reported a very pleasant experience and had significantly less postoperative pain while analgesic use was significantly reduced in this group. Hospital stay was also significantly shorter, providing a substantial reduction of the medical care costs. The postoperative convalescence was significantly improved after HYP and full return to social or professional activity was significantly shortened. We conclude that HYP is a very efficient technique providing physiological, psychological and economic benefits to the patient.

AbstractThe authors describe a left adrenalectomy for Cushing’s disease with the aid of an AESOP (Automated Endoscopic System for Optimal Positioning) 2000 voice controlled robot. This device facilitated the procedure by producing a constant, stable picture allowing the operative team to concentrate principally on the dissection.

A technique for revascularizing the arterial supply to an orthotopic liver transplant (OLT) in a 55‐year‐old male afflicted with end‐stage alcoholic liver cirrhosis with portal hypertension is reported. The presence of well‐developed portosystemic collaterals and an unsuitable recipient common hepatic artery necessitated the dissection and liberation of the right gastroepiploic artery (RGEA) for its subsequent use as the recipient arterial source. Posttransplantation, save for an early biliary leak which was corrected promptly, the patient's evolution was uneventful. Two separate celiac angiographic series at 6 weeks and 20 months posttransplantation revealed an excellent flow through the recipient and donor arterial systems. Additionally, the RGEA demonstrated an adaptation in caliber when pre‐ and posttransplantation angiograms were compared. It was concluded that the RGEA is a suitable rescue option for revascularization of OLT's provided it satisfies elementary hemodynamic requirements.

With the advent of cyclosporine‐A immunotherapy during the initial post‐transplantation period, many factors which govern the donor allograft, organ procurement and recipient host have become more important for avoiding or reducing the incidence of non‐immunological delayed graft function. We analyzed data collected from 61 consecutive cadaver kidney transplantations and applied a multivariate stepwise logistic regression analysis to 11 risk factors recorded from donor and recipient patients during the critical pre‐ and immediate postoperative period. Among the variables studied, four risk factors were selected, which jointly provide optimal prediction of immediate renal allograft function. These are dopamine donor management, immunosuppressive treatment, recipient mean pulmonary artery pressure and cold ischemia time. We determined a prognostic index and designed a table of probabilities of delayed graft function. Individual optimal strategies are suggested for the initial use of CsA which minimize its additive nephrotoxic side‐effect in the setting of a freshly transplanted cadaver kidney.

Reports of laparoscopy in heart graft recipients are scarce and, to our knowledge, laparoscopic colectomy has not yet been reported in heart transplant patients. The magnitude and the tolerance of the hemodynamic changes induced by pneumoperitoneum are unknown in heart. graft recipients, who have a denervated heart and are “preload‐dependent”. The authors report the clinical courses of 2 heart graft recipients who developed acute diverticulitis without perforation or peritonitis and who underwent laparoscopic‐assisted colectomy without complications.

AbstractFulminant hepatic failure is an infrequent but dreadful disease, occurring usually in young patients. Despite fulminant hepatic failure is reversible in most of the cases, some patients develop brain edema and intracranial hypertension, which are the most common cause of death in these patients. Liver transplantation significantly improves the prognosis of selected patients in who precise criteria predict a low chance of survival. This review summarizes the modern standard of care of patients with fulminant hepatic failure, with particular underlining of the management of brain oedema and intracranial hypertension.

Two radioimmunological techniques for the measurement of anti-α-galactosyl (anti-Gal) antibodies were developed and we demonstrated that this antibody is present in the serum of most untreated patients with Graves’ disease, thyroid-associated ophthalmopathy (TAO) and autoimmune thyroiditis. Thyrotropin-binding inhibiting immunoglobulins (TBII) and Thyroid Stimulating Antibodies (TSAb) are frequently found in serum of patients with Graves’ disease but not with autoimmune thyroiditis. Although TBII and anti-Gal were found sometimes simultaneously in the same serum samples, we demonstrated that anti-Gal could be present in the absence of TBII and reciprocally.

Escherichia coli strain K12 8M14, carrying plasmid R751 (51.4 kb; Tp^r, Tra+, IncP), was used as donor in matings with reference strains of the six Brucella nomenspecies, not known so far to harbor naturally occurring plasmids. R751 was easily transferred to and between Brucella spp., at frequencies ranging between 10^-1 and 10^-4. All Brucella transconjugants stably maintained plasmid R751 both in vitro and in vivo in our experimental conditions. No genetic modification of the plasmid during and after the conjugal transfer process could be deduced from the comparative restriction analysis (BamHI, HindIII, and EcoRI) in each Brucella transconjugant and in the E. coli donor. Copyright 1993, 1999 Academic Press

Escherichia coli and Salmonella strains resistant to gentamicin and apramycin were isolated from cattle in France and Belgium and from patients in hospitals. Homology between plasmids of both human and animal origins encoding aminoglycoside 3-N-acetyltransferase was revealed by digestion with several restriction endonucleases and confirmed by hybridization with different replicon-specific probes.

In summary, we established that a significant production of the monokines interleukin‐6, tumor necrosis factor apha, and interleukin‐1 occurred during orthotopic liver transplantation whereas the lymphokines interferon gamma and interleukin‐2 were not detected. Levels of interleukin‐6 reached their maximum values before and especially at the end of the anhepatic phase. They remained high after the anhepatic phase, i. e. after reperfusion of the new livers. Tumor necrosis factor alpha and interleukin‐1 reached their maximum values after the anhepatic phase. Not only were interleukin‐6, tumor necrosis factor apha, and interleukin‐1 present in the serum but they could also be detected in the bile produced by these new livers. Mechanisms of monokine production during orthotopic liver transplantation is multifactorial in origin and further studies will have to evaluate the relative contribution of the various factors involved. The possibility of an association between peroperative monokines and transplant outcome and their potential clinical implication will have to be elucidated.

Immunosuppressed patients are susceptible to complicated diverticulitis, but reports of this complication are scarce in heart graft recipients. To estimate the prevalence of acute diverticulitis in heart graft recipients, we retrospectively reviewed the cases of diverticulitis in a series of 143 patients who underwent orthotopic heart transplantation in a period of 10 years. Six (4%) of these developed acute diverticulitis and required colectomy. All of them were male patients and were older than 50 years. Four patients underwent urgent laparotomy and colon resection with end colostomy (Hartmann procedure). The two other patients suffered from diverticulitis without generalized peritonitis and underwent laparoscopic sigmoidectomy with direct transanal end-to-end anastomosis. The postoperative outcomes of these six patients were satisfactory. As are other immunosuppressed patients, heart graft recipients are susceptible to diverticulitis. Early surgical management may be safe in well-compensated patients.

The case reports of three patients who received cancer-bearing organs at this institution are presented. A fourth recipient, who was to be transplanted with a cancerous kidney, was spared this disastrous complication. The relevant data regarding the donors is also alluded to, with special reference to the type and site of the primary malignancy. Following these case reports, the implications of these issues, their possible prevention, and further management are discussed.

Abstract: Fluid management and assessment of organ perfusion in organ donors with hypotonic polyuria remain poorly investigated problems. In our protocol, urinary losses (565202 ml/h) were replaced volume for volume by 3.3% dextrose/0.3% natrium chloride solution (Baxter) with 20 mmol/l potassium chloride. Concentrated red blood cells were administered to maintain hematocrit at about 30%, and volume expansion (central venous pressure above 6 mmHg) was obtained by gelatin (Haemaccel) infusion. In all donors (n=9), plasma electrolytes remained within normal limits despite hypotonic polyuria. Suppression of initial plasma renin activity (PRA; 9.73.6 ng/ml per hour) was obtained by subacute volume expansion. In eight donors the hemodynamic status improved, dopamine administration, when used, was discontinued, and PRA decreased (2.30.7 ng/ml per hour;P<0.05). The only donor who failed to respond to fluid therapy had increased PRA (24.2 ng/ml per hour). During fluid challenge, an inverse relationship was demonstrated between mean arterial pressure and PRA in all nine donors (r=−0.61;P<0.001), while there were no significant changes in blood urea, creatinine, or urine output. It is concluded that in organ donors, proper maintenance of the hemodynamic status and suppression of the renin stress response may be obtained by an adequate fluid management, involving both qualitative restoration and expansion of intravascular volume.

By using α-phenyl N-tert-butyl nitrone (PBN) as spin trap molecule and the electron paramagnetic resonance (EPR) technique, we obtained the first direct evidence of in vivo intervention of free radicals during an ischemia (50 minutes) reperfusion phenomenon in kidney of an intact rabbit.An EPR signal (triplet of doublets) characterized by coupling constants aN = 14.75-15 G and aHs = 2.5-3 G was detected in blood samples. The signal was consistent with a nitroxyl-radical adduct resulting from the spin trapping by PBN of either oxygen-or carbon-centered radicals. Control experiments indicated that the EPR signal was not due to a toxic effect of the spin trap molecule.

Perfluorocarbons (PFCs) and their emulsions (PFCEs) were used in organ preservation before transplantation, but not in organ perfusion. Our purpose was to achieve organ perfusion with a PFCE at room temperature or at 37°C, i. e. with oxygenation, to prevent damages related to reoxygenation after hypoxia. Therefore, we first investigated the effect of such emulsions on endothelial cells, the first cells to be in contact with the emulsion. A stem emulsion was prepared from perfluorooctyl bromide (90%w/v), emulsified with egg yolk phospholipids (2%w/v) and stabilized with a mixed fluorocarbon-hydrocarbon “molecular dowel” (1,4%w/v) (droplets of ca 0.2 μm in diameter). This emulsion was found to be stable when diluted with cell culture media or organ preservation fluids. Endothelial cells from human umbilical vein (HUVECs) were cultured in multiwell plates in M199 medium (with growth factors, 10% foetal calf serum and 5% human serum). Confluent cells were incubated overnight with 51Cr, washed and overlayed with M199 (control) or the above PFCE diluted 2 × or 4 × with M199 (test). After incubation, the cytotoxicity of the PFCEs was estimated by measuring 51Cr release and observing cell morphology by electron and light microscopy.The percentages of released 51Cr were identical to those of the control cells for the 2 × 3 × or 4 × diluted PFCEs at 4, 25 or 37°C. After return to the M199 medium, the cells grew and multiplied normally. We conclude that the diluted PFCEs were devoid of cytotoxicity. The 2 × diluted PFCE was however partially taken up by the cells: by microscopy, we observed intracellular PFC droplets and by density gradient analysis we found a slight increase in cellular density. The diluted PFCEs were compared to classical organ preservation solutions: HUVECs were incubated with UW (University of Wisconsin) or EC (EuroCollins) solutions at +4 and 37°C (3, 17 or 24 h of incubation). The solutions were observed to be toxic to the cells under these conditions, with cell mortality after return to the M199 medium. This cytotoxicity may be attributed to the high K+ concentration of UW and EC, since similar assays performed on HUVECs with Hank's solution adjusted to 100 mM K+ showed a similar % of 51Cr release. UW and EC are therefore not acceptable as dilution media for PFCEs.

AbstractTransplanting a kidney graft harvested from a live donor has been proposed and used to shorten the waiting time of kidney transplant candidates and to increase the graft pool. Live donor renal transplants have demonstrated better results in term of graft survival rates, compared to renal transplants harvested from brain dead donor. Recently, laparoscopic live donor nephrectomy has been introduced to reduce the live procurement morbidity. This lower morbidity may result in increased acceptance of the donor operation. We initiated a program of laparoscopic live donor nephrectomy in January 1997 and up until June 1998, three cases were successfully performed in our department. The purpose of this paper was to report the first case of this program and its first year of follow-up.

AbstractImmunocompromised patients are particularly at risk for complicated diverticulitis. They are more sensitive to infections and develop fewer abdominal symptoms. When they develop diverticulitis, the course of the disease is very often complicated by free colonic perforation and peritonitis leading to high mortality rates. The purpose of this paper was to review natural course and the management of diverticulitis in the immunocompromised patients.

Between January 1985 and December 1988, 20 pateints over the age of 55 years (extremes 56–63 years; 15 men and 5 women) underwent cardiac transplantation. The cause of cardiopathy was ischemic in 70% of the cases. The immunosuppressive regimen consisted of cyclosporin A, corticoids, and azathioprine. Rejection episodes were monitored by endomyocardial biopsies and treated by pulses of corticoids or monoclonal antibodies (OKT3). The operative mortality was 10% (n=2). The 1-year survival rate was 70%. The 1-year incidence of infection and/or rejection episodes was 1 and 1.53 episodes/patient, respectively. One patient was successfully retransplanted after 9 months because of intractable rejection. Age beyond 55 years is no longer a contraindication to cardiac transplantation. This change in recipient selection policy should lead to parallel changes in donor selection criteria.

AbstractOnly a few cases of combined liver and heart transplantation have been reported in the literature, and no standard surgical procedure has yet been established. We report the successful transplantation of both liver and heart in a 28‐year‐old patient suffering from homozygous beta‐thalassemia. We used Belghiti's technique of inferior vena caval flow preservation for liver transplantation, which avoids inferior vena cava occlusion by a side‐to‐side caval anastomosis. Applied to combined liver and heart transplantation, preservation of caval flow during liver transplantation may allow early discontinuation of cardiopulmonary bypass and, thus, minimize the general consequences of prolonged bypass.