Necrotizing fasciitis of the lower limb after venous surgery: cases studies and a review of the literature.

We report 2 cases of necrotizing fasciitis following stripping of the long saphenous vein and phlebectomy of varicose collateral vessels. The first one concerns a 42-year-old man who presented with a left thigh postoperative infection, evolving despite oral antibiotic therapy. Urgent surgical exploration proved an extensive necrosis consistent with necrotizing fasciitis. Wide excision of the necrotic tissue was performed. Under intravenous antibiotic therapy, local wound care and hyperbaric oxygen therapy, the patient's condition improved. The second case concerns a 60-year-old man with cardio-vascular disease and diabetes. He was transferred in our institution 7 days after surgery for an infection in the right thigh and septic shock. Immediate surgical exploration showed extensive necrotizing fasciitis of the thigh, popliteal fossa and latero-posterior compartments of the leg. Muscle necrosis of the right leg was also observed. A right supra-condylar amputation was performed. The patient improved under antibiotherapy and hyperbaric oxygen therapy.

Molecular cloning and tissue distribution of rat sarcosine dehydrogenase.

Sarcosine dehydrogenase (SarDH) is a mitochondrial flavoenzyme involved in the oxidative degradation of choline to glycine. The absence of SarDH activity in humans is genetically transmitted and is the cause of an amino acid metabolism disorder called sarcosinemia. Tryptic fragments of the purified enzyme from rat liver were subjected to Edman degradation and the sequences obtained were used to clone the cDNA encoding the full length protein. The deduced amino acid sequence of SarDH shares an overall similarity of 47% with dimethylglycine dehydrogenase (Me2GlyDH), another flavoenzyme involved in the mitochondrial choline catabolism with a similar FAD-binding domain. Covalent binding of FAD to SarDH was demonstrated by the observation of strong fluorescence at 530 nm under excitation at 450 nm of the enzyme immunoprecipitated under denaturing conditions from liver extracts. The localization of SarDH immunoreactivity in the mitochondrial matrix was confirmed by Western-blot analysis of purified mitochondrial fractions. Finally, the tissue distribution of SarDH was investigated by Northern-blot analysis of total RNA and Western-blot analysis of total protein from several rat tissues. A strong expression in the liver, but also in the lung, pancreas, kidney, thymus, and oviduct was observed. We therefore suggest that the enzymes of the choline catabolism pathway are important also for metabolism in nonhepatic tissues.

[Acute non-obstructive necrotizing enterocolitis in adults]. / Les entérocolites aiguës nécrosantes non obstructives de l'adulte.

Acute non-obstructive necrotizing enterocolitis in adults is characterized by pathological features: it is an intestinal necrosis beginning in the mucosa, without obstruction of the mesenteric vessels. The disease occurs in a variety of circumstances which may be roughly divided into infections and fall in proximal or distal mesenteric flow rate, the infectious and circulatory mechanisms often coexisting. Little information on the diagnosis is provided by clinical and paraclinical data. Management is medical and/or surgical; it includes alleviation of the symptoms in intensive care unit, attempts at producing local vasodilation whenever possible and resection of the intestinal segment affected. In many cases the diagnosis is made at exploratory laparotomy. The prognosis is poor; it depends on the patient's age, on the extent of the lesions which sometimes require wide intestinal resections, and on the time to diagnosis.

[Post-translational maturation of peptides of the glucagon family. Relationship with their mode of action]. / Maturation post-traductionnelle des peptides de la famille du glucagon. Relation avec leur mode d'action.

Two types of proglucagon processing have been evidenced in producing tissues (endocrine pancreas, stomach, intestine, central nervous system) using antibodies recognizing the epitopes unmasked during processing, which takes place at dibasic sites. A first type, leading essentially to glucagon, has been observed in the two former tissues; a second type, leading to peptides (oxyntomodulin and glicentin) containing an additional C-terminal octapeptide, has been shown in the two latter. All peptides are released in plasma and reach their targets: liver, fat... (control of metabolism) for glucagon and gastric mucosa (control of acid secretion) for the octapeptide-bearing peptides. The mode of action of these peptides includes receptors coupled to adenylate cyclase and a processing, at a dibasic site, of the circulating peptides leading to C-terminal fragments which act through non cyclic AMP-dependent mechanisms, such as the control of the plasma membrane calcium pump.

Oxyntomodulin and glicentin: brain-gut peptides in the rat.

Glucagon-like materials and glucagon have been identified by immunoassay and immunocytochemistry in the mammalian central nervous system. However, the molecular forms relevant to brain glucagon-like immunoreactivity (GLI) have not been precisely defined. In the rat small intestine, more than 90% of GLI is constituted by two peptides: oxyntomodulin (OXM) and glicentin. This work was initiated to characterize and determine the concentrations of these two peptides and glucagon in the rat central nervous system and to compare their relative proportions with those found in the gut. Different regions from the adult rat brain were analyzed by HPLC in association with RIA, using a central glucagon antiserum and an antibody directed toward the C-terminal end of OXM and glicentin. The elution profiles of hypothalamus extracts were constituted by two main peaks, both detected by the two antibodies used and displaying the same retention times as glicentin and OXM, respectively. A third small peak, which coeluted with glucagon, was constantly recorded with the central glucagon antiserum. The percentages of glicentin, OXM, and glucagon in 10 hypothalami were 37 +/- 1%, 55 +/- 1%, and 8 +/- 2%, respectively (n = 8). This distribution was quite similar to that in small intestinal extracts (38 +/- 1%, 59 +/- 1%, and 1.3 +/- 0.1%, respectively; n = 7); however, the peptide concentrations were almost 50-fold greater in intestine than in hypothalamus. In the medulla oblongata, the same peptide ratio was observed, with 10-fold lower concentrations compared to those in hypothalamus. In olfactory bulb, cerebellum, and cortex the concentrations were close the the detection limit, whereas they could be not detected in the pituitary. The combination of HPLC and specific RIAs allowed us to unambiguously characterize OXM and glicentin as the major components of GLI in the rat hypothalamus and medulla oblongata. The same proportion of these two peptides in the central nervous system and the gut indicates that a similar posttranslational processing exists in these rat tissues, another example of the brain-gut axis.