PubMed Health⌕ Search

Biomedical subjects

M Meurisse

Publications and source records attributed to M Meurisse.

At least 19 recordsLinked to original sources

Evaluation of the ultrasonic dissector in thyroid surgery. A prospective randomised study.

BACKGROUND: The use of ultrasonic dissectors in endoscopic surgery has proved to be of value, particularly for the prevention of bleeding and the reduction of electrical internal burns. This prospective randomised study was performed in order to evaluate the efficacy, security and cost of using the ultrasonic hook in thyroid surgery. METHODS: Thirty-four consecutive euthyroid patients with multinodular goitre for whom a total thyroidectomy was indicated, were randomly assigned either to group I, Ultracision or to group II, conventional hemostasis. Pre-, peri-, and postoperative biochemical, clinical, surgical and economical variables were compared between both groups. RESULTS: The use of the ultrasonic hook resulted in a significant reduction in operating time, blood loss, and maybe in "transitory hypoparathyroidism"; postoperative analgesic consumption was also reduced in this group. Considering the cost, the ultrasonic hook was no more expensive than conventional hemostasis, as long as a minimum of 15 patients shared the initial unit cost of the device. CONCLUSION: Even if the use of the ultrasonic dissector is not of major interest in terms of patient management or cost-saving in the context of total thyroidectomy, essential advantages reside in significant reductions of operating time, blood loss and organ injury, (particularly parathyroid). The reduced operating time undoubtedly represents a positive feature of the ultrasonic dissection technique.

Goiter, Nodular↗

Breast cancer and serum organochlorine residues.

BACKGROUND: Controversy still exists about the breast carcinogenic properties in humans of environmental xenoestrogens (organochlorines), justifying new investigations. AIMS: To compare the blood levels of total dichlorodiphenyltrichloroethane (DDT) and hexachlorobenzene (HCB) in samples collected at the time of breast cancer discovery, in order to avoid the potential consequences of body weight change (after chemotherapy or radiotherapy) on the pesticide residue levels. METHODS: Blood levels of HCB and total DDT (we calculated total DDT concentrations by adding all DDT and DDE isomers) were compared in 159 women with breast cancer and 250 presumably healthy controls. Risk of breast cancer associated with organochlorine concentration was evaluated. RESULTS: Mean levels of total DDT and HCB were significantly higher for breast cancer patients than for controls. No differences in serum levels of total DDT or HCB were found between oestrogen receptor positive and oestrogen receptor negative patients with breast cancer. CONCLUSIONS: These results add to the growing evidence that certain persistent pollutants may occur in higher concentrations in blood samples from breast cancer patients than controls.

Breast Neoplasms↗

[Discordance between actual and radiologically estimated size of an incidentaloma. Delay in questions regarding operative decision-making criteria].

AIM OF THE STUDY: The accurate assessment of tumour size is an important consideration during preoperative evaluation of adrenal tumors, particularly incidentaloma; however the "size criteria" is still a controversial topic in some respects: size is a bad indicator of malignancy, there is still a confusion in the "grey zone" for tumors between 3 and 6 cm, and no universal consensus on the exact cut-off value for resection has been agreed. Nowadays it is clearly accepted that the "size criteria" alone is extremely limited in the assessment of adrenal tumor, moreover some studies suggested the relative inaccuracy of conventional CT in evaluating the size: radiological examination underestimated consistently adrenal tumor size. The aim of this study was to confirm those suggested data. PATIENTS AND METHODS: Our study compared the radiological estimated size and the histological size of 26 incidentaloma operated on with a laparoscopic approach. RESULTS: Our data confirm the inaccuracy of CT and MRI in predicting the size of incidentaloma particularly for tumor measuring less than 3 cm. CT and MRI significantly underestimated size of adrenal tumors, 108% for MRI and 101% for CT-scan. CONCLUSION: The decision to operate, even with the advent and safety of laparoscopic adrenalectomy, cannot only rely on the "size criteria". Radiologists have to perform multiple 1 mm cuts until the very superior and inferior tip of this tumor in order to provide a better estimation of the size.

Adrenal Gland Neoplasms↗

New challenges in the treatment of early breast cancer or surgery for early breast cancer ... can less be more?

Breast cancer is a major public health problem of great interest and importance to physicians in a variety of specialities. The incidence of the disease has increased dramatically, heightening concern among physicians and women in general. In addition, long-term results are now available from clinical trials initiated in the 1970s and 1980s to evaluate the usefulness of early detection with mammography and physical examination, breast-conserving treatment with limited breast surgery and irradiation, and adjuvant systemic therapy with hormonal therapy and chemotherapy. Furthermore, in the light of newly gained knowledge, new strategies for addressing this problems have been proposed. In this review, we will summarize the evidence evaluating the strategies for diagnosis and therapy initiated in the 1970s and 1980s, and will describe the prospects for prevention and for more specific treatments bases on evolving biologic knowledge. Our review will only focus on early breast cancer, discussing the following topics: Breast Cancer screening: Who should be screened and how often?; New technologies in Breast Cancer Diagnosis; Selection of patients for Breast-conserving therapy; Management of the axilla in primary breast cancer or "Is sentinel lymph node biopsy useful?"; Expanded use of adjuvant systemic therapy; Genetic predisposition for Breast Cancer; Clinical options for Women at high-risk for Breast Cancer.

Breast Neoplasms↗

[Diagnosis and treatment of pancreatic injuries in children].

Pancreatic injury after trauma can occur in the child as an isolated lesion after a minor injury. The consequences can be severe in the absence of prompt diagnosis and treatment. Determination of mechanism of injury, clinical examination, blood amylase levels and abdominal CT-scan are first line steps for the evaluation of the injury. ERCP and MRI can be useful tools to further document injury to the pancreatic duct. In the absence of duct injury, conservative treatment can be applied. For the other cases, the treatment is surgical although newer techniques may be applied in selected cases.

Abdominal Injuries↗

Distribution and co-localization of choline acetyltransferase and p75 neurotrophin receptors in the sheep basal forebrain: implications for the use of a specific cholinergic immunotoxin.

The basal forebrain cholinergic system is involved in different forms of memory. To study its role in social memory in sheep, an immunotoxin, ME20.4 immunoglobulin G (IgG)-saporin, was developed that is specific to basal forebrain cholinergic neurons bearing the p75 neurotrophin receptor. The distribution of sheep cholinergic neurons was mapped with an antibody against choline acetyltransferase. To assess the localization of the p75 receptor on basal forebrain cholinergic neurons, the distribution of p75 receptor-immunoreactive neurons with ME20.4 IgG was examined, and a double-labeling study with antibodies against choline acetyltransferase and p75 receptor was undertaken. The loss of basal forebrain cholinergic neurons and acetylcholinesterase fibers in basal forebrain projection areas was assessed in ewes that had received intracerebroventricular injections of the immunotoxin (50, 100 or 150 microg) alone, as well as, in some of the ewes treated with the highest dose, with bilateral immunotoxin injections in the nucleus basalis (11 microg/side). Results indicated that choline acetyltransferase- and p75 receptor-immunoreactive cells had similar distributions in the medial septum, the vertical and horizontal limbs of the band of Broca, and the nucleus basalis. The double-labeling procedure revealed that 100% of the cholinergic neurons are also p75 receptor positive in the medial septum and in the vertical and horizontal limbs of the band of Broca, and 82% in the nucleus basalis. Moreover, 100% of the p75 receptor-immunoreactive cells of these four nuclei were cholinergic. Combined immunotoxin injections into ventricles and the nucleus basalis produced a near complete loss (80-95%) of basal forebrain cholinergic neurons and acetylcholinesterase-positive fibers in the hippocampus, olfactory bulb and entorhinal cortex. This study provides the first anatomical data concerning the basal forebrain cholinergic system in ungulates. The availability of a selective cholinergic immunotoxin effective in sheep provides a new tool to probe the involvement of basal forebrain cholinergic neurons in cognitive processes in this species.

Animals↗

Extensive immunolesions of basal forebrain cholinergic system impair offspring recognition in sheep.

The involvement of the basal forebrain cholinergic system has been extensively investigated in instrumental learning but little is known of its participation in social memory, especially in the memorization of individual traits of a conspecific. The present study tested in sheep its contribution to both instrumental learning and individual offspring recognition. Six weeks before parturition, ewes received injections of a specific cholinergic immunotoxin (ME20.4 IgG-saporin) into the lateral ventricles (150 microg) and in some cases additional immunotoxin injections into the nucleus basalis (11 microg/side). After 3 weeks of recovery, ewes were trained on a classical instrumental visual discrimination task known to be sensitive to cholinergic deficits. The formation of memory of offspring was assessed through both olfactory and visual/auditory recognition tasks. Olfactory recognition was tested by presenting at suckling successively an alien and the familiar lamb at 2 and 4 h after parturition. Visual/auditory recognition of the lamb was performed using a non-olfactory discrimination test between the familiar and an alien lamb after 12 h of mother-young contact. The lesion extent was assessed by counting choline acetyltransferase-immunopositive neurons in the basal forebrain and measuring the density of acetylcholinesterase fibers in different target areas. Results showed that immunotoxic lesions delayed acquisition of the instrumental visual discrimination. Moreover, olfactory recognition of the lamb was severely impaired while visual/auditory lamb recognition was marginally altered. There was no evidence for sensorimotor or motivational deficits. Importantly, impairment was observed in animals for which loss of basal forebrain cholinergic neurons and their efferent fibers was higher than 75%, while striatal cholinergic neurons and Purkinje cells were unaffected. This study provides evidence that the basal forebrain cholinergic system contributes not only to instrumental but also to social learning. In addition, the cholinergic modulation seems of importance for processing visual and olfactory modalities. However, since only extensive lesions affect performance, this indicates that the basal forebrain cholinergic system possesses substantial reserve capacity to sustain cognitive functions.

Acetylcholine↗

Right hepatic lobectomy as a liver graft-saving procedure.

Retransplantation is common after liver transplantation (LT). However, in the present era of organ shortages, every attempt to save the liver graft should be performed before considering retransplantation. We report our experience with right hepatic lobectomy (RHL) for liver graft salvage. In a retrospective series of 180 adult LTs, 4 patients underwent RHL (Couinaud's segments V, VI, VII, VIII) in the post-LT period. In all cases, the procedure was performed without Pringle's maneuver or mobilization of the left liver lobe to preserve its vascularization. Three liver graft recipients developed intrahepatic biliary strictures, mainly localized to the right lobe of the graft, and RHL was performed 14, 75, and 78 months after LT. These patients were alive at last follow-up without further episodes of cholangitis or retransplantation (mean follow-up, 38 months). The fourth patient developed early post-LT right liver necrosis with a functioning hepatic artery and underwent right lobectomy 48 hours after LT. He later developed cholangitis secondary to late hepatic artery thrombosis, requiring retransplantation after 18 months. We conclude that RHL can be considered a graft-saving option in selected liver transplant recipients with localized biliary strictures, with excellent patient and graft survival.

Bile Ducts↗

Seventy-two hours hypothermic intestinal preservation study using a new perfluorocarbon emulsion.

We investigated the effect of a perfluorocarbon emulsion (FC) added to the University of Wisconsin (UW) solution on hypothermic (4 degrees C, 12-72h) preservation of rat small bowel grafts. The FC was 90%w/v perfluorooctylbromide, 2%w/v egg yolk phospholipids and 1.4%w/v mixed fluorocarbon-hydrocarbon molecular dowels. Four groups were defined: [1] UW flush and UW storage; [2] UW flush and FC storage; [3] flush with FC diluted 2 times with UW (FU) and FU storage; [4] FU flush and storage in oxygenated FU. Preservation was estimated with a histological score based on villus epithelium adhesion, on villus sloughing and on crypt cell adhesion to the basal membrane. Antioxidant potential was estimated by measurement of total thiol functions (SH) and activities of glutathione-peroxidase (GSH-P), superoxide dismutase (SOD) and catalase. FC in flush improved preservation during the first 24h (p<0.01). Storage in FC appeared superior to UW for the first 24h (p<0.01). Oxygenation (100% O2) of the storage medium yielded superior results at 12h and 24h (p<0.01 and p<0.001 versus group [1] respectively). After 72h, SOD and catalase activities increased in groups [3] and [4], and SOD decreased in group [1] (p<0.05). SH progressively decreased in group [1] (p<0.05) and GSH-P increased at 24 and 48h in groups [3] and [4] (p<0.01). The increase of O2 in the perfusion flush or storage medium ameliorated the preservation status and protected the antioxidant potential of the small bowel.

Animals↗

[Update on pancreatic transplantation].

Pancreas transplantation significantly improves the quality of life as well as the survival of the diabetic patient. It is also associated with stabilization and reversal of secondary diabetic complications. Improvements in organ preservation, surgical techniques and immunosuppression have achieved one-year graft survival of more than 90% for combined kidney-pancreas transplant and 80% for isolated pancreas transplantation. Recipient evaluation must weigh the benefits of the procedure with the risk associated with surgery and chronic immunosuppression. Combined kidney-pancreas transplantation appears today as the best treatment for the diabetic patient with end stage renal disease. Isolated pancreas transplantation is reserved to non-uremic patients with severe diabetic complications or with brittle glycaemic control and severe impairment of quality of life.

Humans↗

[Alpha-1-antitrypsin deficiency. An indication for pediatric liver transplantation].

Alpha-1-antitrypsin deficiency is the most common inborn error of metabolism leading to liver transplantation, and the second cause of liver transplantation in children after biliary atresia. The authors report the case of a 6-year-old girl, who was suffering from end-stage liver disease secondary to alpha-1-antitrypsin deficiency. She was successfully treated by whole liver transplantation, the hepatic graft coming from a 3-year-old donor. Three months later she went back to school. The authors discuss the pathogenesis and the natural history of this frequent cause of liver transplantation in children.

Child↗

[Lung transplantation and mitochondrial function].

The mechanisms of cellular lesions induced by lung ischemia and reperfusion are not fully understood and, in particular, the consequences of pulmonary ischemia and reperfusion injury on mitochondrial function have not been previously investigated. Therefore, we studied the respiratory function of isolated pulmonary mitochondria in a swine model of lung ischemia and reperfusion. We demonstrated that prolonged hypothermic (4 degrees C) ischemia induces significant lesions of the mitochondrial respiratory chain, particularly if ischemia is followed by normothermic reperfusion. These results should be integrated in the cellular alterations induced by the ischemia-reperfusion injury. In another swine model mimicking controlled non-heart beating donors, we demonstrated that thirty minutes of cardiac arrest do not promote significant alteration of the mitochondrial respiratory function. In contrast, forty-five minutes of cardiac arrest, induced significant mitochondrial lesions. This pulmonary tolerance to normothermic cardiac arrest might be explained by the presence of air in the lung airways, allowing some aerobic metabolism after circulatory arrest. These results suggested that lung grafts might be harvested from non-heart beating donors after thirty minutes of cardiac arrest, significantly increasing the pulmonary graft pool.

Animals↗