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Biomedical subjects

L Michel

Publications and source records attributed to L Michel.

At least 145 records · Page 8Linked to original sources

Esophageal resection and by-pass: a 6 year experience with a low postoperative mortality.

From 1984 to 1989, 175 esophageal cancer patients, 10 patients admitted for severe caustic esophagitis, and 1 patient with pyothorax due to iatrogenic perforation of the esophagus underwent an esophageal resection or bypass operation. One hundred sixty-eight esophageal resections were performed on 167 patients; 13 were total, 106 subtotal and 49 distal. Nineteen digestive transplants were pulled up to the neck to bypass the esophagus or re-establish continuity after an esophagectomy made elsewhere. Digestive continuity was restored by a long gastric transplant in 120 patients, a colon segment in 17, a jejunal loop in 35, and a short gastric transplant after limited esophago-gastrectomy in 14 patients. Thirty day mortality was 0 in the whole group. Hospital mortality was 1.2% in the resection group and 10.5% in the bypass group (p = 0.048). Nonfatal postoperative complications consisted of respiratory distress in 33 patients, recurrent nerve palsy in 10, anastomotic fistula in 10 (cervical in 8 and intrathoracic in 2) and anastomotic stenosis in 18 patients. Respiratory complications were more frequent in patients with a cancer of the thoracic esophagus (29/111) than in those operated on for a cancer located in the esophago-gastric junction (4/50) (p less than 0.01). Anastomotic stenosis occurred more frequently in the neck (17/137) than in the chest (1/49) (p less than 0.05). Nine patients were reoperated on for a technical complication; intraabdominal hemorrhage (1), thoracic duct injury (2), acute cholecystitis (1), tight stricture of the esophageal anastomosis (2), jejuno-duodenal anastomotic fistula (2), or stridor related to recurrent nerve palsy (1).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

A review of the general aspects of radiofrequency ablation.

As an alternative to standard surgical resection for the treatment of malignant tumors, radiofrequency ablation (RFA) has rapidly evolved into the most popular minimally invasive therapy. To help readers gain the relevant background knowledge and to better understand the other reviews in this Feature Section on the clinical applications of RFA in different abdominal organs, the present report covers the general aspects of RFA. After an introduction, we present a simple definition of the energy applied during RFA, a brief historical review of its technical evolution, and an explanation of the mechanism of action of RFA. These basic discussions are substantiated with descriptions of RFA equipment including those commercially available and those under preclinical development. The size and geometry of induced lesions in relation to RFA efficacy and side effects are discussed. The unique pathophysiologic process of thermal tissue damage and the corresponding histomorphologic manifestations after RFA are detailed and cross-referenced with the findings in the current literature. The crucial role of imaging technology during and after RFA is also addressed, including some promising new developments. This report finishes with a summary of the key messages and a perspective on further technologic refinements and identifies some specific priorities.

Abdominal Neoplasms↗

[Guidelines for substitution treatments in prison populations].

Care access for the drug addict patients in prison (in particular for the treatments of substitution) in France is very unequal from one establishment to another. This reflects the great variability of the practices of substitution and especially the absence of consensus on the methods of adaptation of these practices to the prison environment. Because of difficulties expressed by prisoners and medical staff on this subject and of stakes (let us recall that approximately 30% of the prisoners are dependent or abusers of one or more psychoactive substances), the formulation of recommendations or of a good practices guide of substitution in prison appeared necessary. Work that we detail here answers a ordering of the Advisory Commission of the Treatments of Substitution (September 2001) whose authors are members. It was presented at the session April 2003. It results from the confrontation of a review of the literature (including legal texts and official reports concerning substitution, the organization of the care in prison environment and the lawful framework), with a vast investigation. The latter was carried out near medical staff (22 prisons), penitentiary staff (3 prisons, 27 people met including directors of these establishments) and prisoners (7 establishments, 28 prisoners met) in the form of individual talks (semi-directing interviews with evaluation of the type of existing device and its knowledge by the penitentiary staff and the prisoners; statement of the suggestions, needs and requests of the medical, penitentiary staffs and of the prisoners). In the whole visited prisons, 7.8% (870) of the prisoners received substitution treatments (6.35% by buprenorphine, 1.44% by methadone), representing a proportion of substituted drug addicts (870 substituted for an evaluation of 3,350 prisoners drug addicts among the 11,168 prisoners of the 22 visited prisons) notably lower than that in free environment (56%, ie 96,000 substituted for an evaluated population of drug addicts for heroin of 160,000). There are however considerable variations (from 0 to 16.2%) of the proportion of substituted of one establishment for the other according to the type of prison, of its size, its localization and the type of medical device present. If a consensus exists for methadone (daily delivery with sanitary control), the organization of the care relating to the buprenorphine is extremely variable from one establishment to another, often putting in difficulty as well the medical teams as the prisoners. One recommendation is essential: the formulation of an individualized therapeutic project. Thirteen other recommendations are made in the following fields: renewal of substitution treatments, initiation of substitution treatments, urinary controls, methods of prescription, methods of delivery, co-prescriptions, global care, confidentiality, files, exits and transfers, extractions, formation, accompaniment of the teams. These recommendations being formulated, many medical concerns remain present and several questions open. The report of joint mission IGAS/IGSJ of June 2001 on the health of the prisoners underlines the principal persistent gaps: hygiene and public health, treatment of the mental disorders, the follow-up of the sexual delinquents, handling ageing, handicap and the end of lifetime. In the same way, the difficulties listed in prison environment concerning substitution are only the exacerbation of those existing outside: the misuses and traffics are common in free environment, risk reduction in prison, as outside, handle with obstacles related to the penalization of the drug use and can hardly evolve except questioning the law of 1970. The prison practice opens also questions: that of the "duration" of the substitution, frequently posed by the prisoners; concern to see the prison becoming a privileged place of access to the care, combining sanction and care whereas the law of 1970 allows the alternative (care or sanction); that of the clinic of the misuse, particularly "readable" in prison environment; and finally the question of the shared secrecy, extremely delicate in prison context although clarified by the law of March 04, 2002.

Forensic Psychiatry↗

Effects of ultraviolet A and antioxidant defense in cultured fibroblasts and keratinocytes.

Lipid peroxidation, measured by the thiobarbituric acid-reactive substances assay, was evaluated for cultured human skin fibroblasts and keratinocytes exposed to ultraviolet A radiation (320-400 nm, UVA). Peroxidation increases with increasing UVA doses and is much lower for keratinocytes than for fibroblasts. Immediate UVA-induced cytotoxicity, monitored by the trypan blue exclusion assay, is also lower for keratinocytes. Thus, cultured human skin keratinocytes are less sensitive than fibroblasts to the immediate deleterious effects of UVA with respect to membrane damage and lipid peroxidation. As a first attempt to understand this lower sensitivity of keratinocytes, basal levels of antioxidant defenses including total glutathione, superoxide dismutase, glutathione peroxidase and catalase were evaluated in both keratinocytes and fibroblasts from the same donors. We failed to correlate this lower susceptibility of keratinocyte to UVA-induced lipid peroxidation and cytotoxicity with a higher antioxidant status.

Adult↗

Hypothetical mechanisms of action of an H1-antihistamine in asthma.

Some recent clinical studies carried out with the potent H1-antihistamine cetirizine (CTZ) suggest that this drug could be useful for the treatment of mild to moderate asthma and even for the prevention of the disease. Besides a potent antagonism of H1-receptors at bronchial level, this drug was also shown to exert a large series of anti-inflammatory effects in in vitro, ex vivo and in vivo pharmacological models and also in clinical situations in atopic subjects. All the data collected up to now suggest the possible existence in the molecule of a central key mechanism of action on resident cells especially involved in cell trafficking and bronchial inflammation, i.e a down-regulating effect on the nuclear factorKappaB (NFkappaB). This hypothesis was tested on human endothelial cells and a human epithelial pulmonary cell line using different experimental methods. The results showed that CTZ down-regulates the TNF-alpha-induced hyperactivation of NFKappaB in these two different resident cells at physiological concentrations.

Adult↗

Reversal of biochemical and functional abnormalities in erythrocytes secondary to selenium deficiency.

A patient with multiple enterocutaneous fistulae on total parenteral nutrition for 14 months developed low erythrocyte selenium and low erythrocyte glutathione peroxidase. Erythrocyte hexose monophosphate shunt activity stimulated with an H2O2 generating system was approximately one-fourth that of control. Hexose monophosphate shunt activity stimulated with methylene blue showed little difference between patient and control. With selenium supplementation erythrocyte selenium, glutathione peroxidase, and hexose monophosphate shunt activity became normal. Thus, the biochemical and functional consequences of selenium deficiency can be corrected with selenium supplementation.

Adult↗

Usefulness of [99mTC]MIBI and [18F]fluorodeoxyglucose for imaging recurrent medullary thyroid cancer and hyperparathyroidism in MEN 2a syndrome.

We report the case of a MEN 2a patient with a history of medullary thyroid cancer (MTC) treated by total thyroidectomy, who presented an increasing calcitonin level, suggesting tumor recurrence. Conventional radiographic and radionuclide imaging failed to localize the responsible lesions. A planar and tomographic (SPECT) [99mTc]MIBI scan, performed in order to investigate a recent hyperparathyroidism localized a parathyroid adenoma and revealed an abnormal uptake in the left lateral neck region, corresponding to apparently banal lymph nodes on MRI. This abnormal uptake was also observed on a [18F]fluorodeoxyglucose positron emission tomography (FDG-PET) study and was proven to be an uptake in MTC lymph nodes metastases as confirmed by histopathologic analysis. We conclude that, using an adequate acquisition protocol (i.e. SPECT), [99mTc]MIBI scan is potentially able to localize both parathyroid adenoma and recurrent MTC at one and the same time, particularly in case of non-diagnostic conventional imaging techniques. In this setting, the potential usefulness of FDG-PET is also discussed.

Adult↗

[Benzodiazepines and forensic aspects].

Adverse effects of benzodiazepines are well known since the first one was used in 1958 (chlordiazepoxide). The literature collects study-cases or rarely controlled studies concerning side effects or paradoxical reactions to benzodiazepines. They mostly described drowsiness and behavioral disinhibition, including increased well-being feeling but also hostility, rage access with feeling of invulnerability, serious crimes and sometimes homicides. Delusional, manic, confusional or depressive states are also pointed out. Rate for aggressive behaviour is 0.3 to 0.7% but distinction should be done between accidental or "idiosyncratic" reaction and voluntary sought disinhibition, clearly more frequent. No benzodiazepine has any specificity for these adverse effects but pharmacology, doses, associated drugs (or alcohol) and psychopathology interact to produce hazardous psychic states. Pharmacology: GABA induces a decrease in serotonin compound and vigilance. Pharmacokinetic: first dose effect or over-dose effect, short half-life, lipophily, affinity, digestive absorption, active metabolites interact. Psychopathology: age, alcohol association, psychological status (high initial level of hostility, impulsivity, frustration, personality disorder and depressive status). External conditions: chronic illness, affective and professional frustrations, physical or psychic exhaustion contribute also. Some benzodiazepines (flunitrazepam, diazepam, clorazepate, triazolam, alprazolam, lorazepam, for example) are more often concerned for pharmacokinetics characteristics but also prescription habits. Forensic aspects should be considered in case of homicide. Especially, reality of benzodiazepines consumption and awareness of the potential paradoxical reaction should be precisely evaluated. Special focus on voluntary induced disinhibition has to be done for forensic considerations. Relationship but also crime facilitations are sometimes consciously sought. Some benzodiazepines have already been identified for this use: flunitrazepam, clorazepate but also triazolam and temazepam in UK, alprazolam in USA. Flunitrazepam is prohibited in USA and considered as narcotics in France. A Swedish study showed that violent acts were more frequent and serious in juvenile offenders taking flunitrazepam/alcohol than other young offenders staying in the same correctional institution. They recommended classification of flunitrazepam as narcotic. A study from Belgium with drug addicts concluded in the same way and asked for an increased information of professionals and a more efficient control of the delivery. Before concluding to idiosyncratic effect, and then possibly to penal irresponsibility, the forensic approach should consider: firstly the reality of the benzodiazepines absorption and implication in committing violence (urine test, chronology, amnesia); secondly, the association of unusual behaviour and converging circumstances (pharmacological, pharmacokinetic, psychopathology, external conditions); thirdly the consumer's knowledge of the disinhibition effect. In our prison practice, we have to be particularly cautious as population frequently associates personality disorder, drug addiction and high level of frustration related to penitential context. Special information should be given to inmates when benzodiazepines are prescribed, but more extensively, a preventive strategy should be adopted in general population.

Aggression↗

[Renal transplantation and Bourneville's tuberous sclerosis].

A kidney transplantation was performed in July 1981 on a 29 year old woman who presented the signs of tuberous sclerosis and suffered from chronic renal failure. The frequency and the genetic transmission of Bourneville's disease are explained. The signs of the disease are exposed with special emphasis on the renal lesions. Only the patients with minor neurological symptoms can survive. These patients are able to develop chronic renal failure. This occurs either when the kidneys are destructed by renal cysts or tumors, or when a bilateral nephrectomy must be performed for bleeding or tumoral compression. A kidney transplantation can give them an opportunity to live almost normally. When nephrectomy is not performed, a regularly follow-up is necessary because the unknown future of the renal lesions in place.

Adult↗

Cerebrovascular circulation "steal" syndrome secondary to a voluminous retrotracheal goiter.

A case of recurrent transient ischaemic attacks in the brain resolved after removal of a voluminous retrotracheal goiter is presented. The presence of congenital atretic left vertebral artery, associated with impairment of left carotid artery blood flow by a very large inferior thyroid artery, probably caused the episodes to transient ischaemic attack.

Brain↗

Gastric rupture: a danger of postoperative oxygenation with a nasal catheter.

On the fifth postoperative day after pulmonary lobectomy, a 64-year-old man accidentally connected his nasal catheter (providing six liters of oxygen per minute) to his nasogastric tube. Tension pneumoperitoneum occurred with acute respiratory distress. Gastric rupture occurring during cardio-pulmonary resuscitation has been reported several times. Our case illustrates another unusual cause of tension pneumoperitoneum. Emergency percutaneous decompression was effected with needle aspiration, followed by laparotomy for gastric repair covered by an omental flap.

Carcinoma, Squamous Cell↗

[Surgery in patients with previous heart surgery. Apropos of 21 patients].

Authors relate 22 non cardiac operations among 21 patients having previously undergone cardiac surgery. Oral anticoagulant therapy was discontinued before non cardiac operation while subcutaneous heparine therapy was initiated. There were no bleeding or thromboembolic complications during the perioperative period or later in the follow-up. In order to prevent bacterial endocarditis, prophylactic antibiotherapy was associated with careful surgical asepsis. No case of endocarditis was encountered during a mean follow-up of 22 months. Cardiac medications such as digitalis and beta adrenergic blockers were maintained as long as possible during the perioperative period while their dosage and clinical effects were closely monitored. No patient did present cardiac failure, significant arrhythmia or blood pressure impairment. No perioperative myocardial infarcts occurred in the group of coronary artery bypass graft patients. Those patients were managed in order to maintain their myocardial muscle work in optimal ranges thanks to selective premedication, brief interruption of beta adrenergic blockers, strict control of fluid balance and careful postoperative pain relief.

Adult↗

[A special aspect of perianal suppuration: Verneuil's disease].

Verneuil's disease is classically described as a chronic hidradenitis suppurativa of the apocrine sweat glands of the skin. It is characterized by the formation of recurrent abscesses of the subcutaneous tissues at the level of areas containing apocrine sweat glands. Extensive chronic inflammatory lesions of skin and subcutaneous tissues can evolve in multiple fistula. Occurrence in the perianal region is rather frequent (32% according to Goligher), but the lesions are often misdiagnosed. Fistula-in-ano are rare. When such is the case, fistula-in-ano are the consequences of a long evolution of the disease, the extension of the superficial lesions in the muscles of the anal sphincters or inappropriate surgical treatment. Five cases having undergone iatrogenic lesions are reported. Diagnosis is mainly a clinical one and has to be confirmed by pathological examination. Treatment is surgical and can bring healing if wide excisions of perianal lesions are conducted in single or multiple stages.

Anus Diseases↗