The possible role of hydroxylamine and imine intermediates in the metabolism of amphetamine and related primary amines is discussed. The inherent instability of imines, has hitherto precluded the recognition of these compounds as metabolites of primary amines. During studies on the metabolism of o-methylbenzhydrylamine using washed hepatic microsomes from a number of mammalian species, the formation of o-methylbenzophenoneimine as a metabolite was observed. This metabolite was identified by preparative thin layer chromatography followed by gas-chromatography combined with mass spectrometry.

Amphetamines↗

PubMedDate not supplied

A novel approach for intestinal elongation using acellular dermal matrix: an experimental study in rats.

We tested the hypothesis that an anatomic scaffold placed in continuity with viable bowel might allow intestinal growth. Male ACI rats were used for the study. Acellular human dermis in the form of tubular scaffolds with an intraluminal diameter of approximately 0.3 cm was oriented with the luminal basement membrane and serosal dermal surface. The small bowel was transected approximately 2 cm distal to the ligament of Treitz. The graft was then anastomosed in continuity in group A (n = 5) or as a blind-ended pouch to a defunctionalized jejunal limb in group B (n = 8). The animals were sacrificed at various time points. Histology and immunohistochemistry were used to evaluate structural changes. Animals in group A developed peritonitis and were all sacrificed within the first week postoperatively. However, all animals in group B survived, increasing their body weight similarly to age-matched rats. Tissue samples obtained at sacrifice showed a progressively increasing amount of cellular infiltrate over time in the matrix. Epithelial regeneration, angioneogenesis, and myofibroblast infiltrate were seen at 2 weeks, while well-formed branching crypts were seen at 4 weeks. Intact mucosa extended across the anastomosis to the grafts at 6 months. This study demonstrated an anatomic scaffold of acellular matrix allowed mucosal regeneration from viable bowel placed in continuity. These findings set the basis for new intestinal elongation techniques.

Anastomosis, Surgical↗

PubMedDate not supplied

Nonlinear dynamic perspectives on dynamic force microscopy.

Dynamic force microscopy (DFM) utilizes the dynamic response of a resonating probe tip as it approaches and retracts from a sample to measure the topography and material properties of a nanostructure. We present recent results based on nonlinear dynamical systems theory, computational continuation techniques and detailed experiments that yield new perspectives and insights into DFM.A dynamic model including van der Waals and Derjaguin-Müller-Toporov contact forces demonstrates that periodic solutions can be represented as a catastrophe surface with respect to the approach distance and excitation frequency. Turning points on the surface lead to hysteretic amplitude jumps as the tip nears/retracts from the sample. New light is cast upon sudden global changes that occur in the interaction potential at certain gap widths that cause the tip to "stick" to, or tap irregularly the sample. Experiments are performed using a tapping mode tip on a graphite sample to verify the predictions.

Journal Article↗

PubMedDate not supplied

Nosocomial zygomycotic post-surgical necrotizing fasciitis in a healthy adult caused by Apophysomyces elegans in south India.

Necrotizing fasciitis caused by the zygomycete Apophysomyces elegans of the anterior abdominal wall of a young healthy woman following a lower segment caesarean section is reported. Early clinical diagnosis and laboratory identification followed by appropriate management involving extensive tissue debridement and adequate doses of amphotericin B were eventually successful in controlling the infection and saving her life.

Adult↗

PubMedDate not supplied

The effects of 2-thiophenecarboxylic acid on serum ionic calcium and magnesium levels in rats.

1. Administration of 2-thiophenecarboxylic acid to rats maintained on a low calcium diet resulted in a significant depression in the serum levels of total and ionized calcium and inorganic phosphate. 2. The serum magnesium levels were not altered by the drug.

Animals↗

PubMedDate not supplied

An assessment of cadmium toxicity on cytochrome P-450 and flavin monooxygenase-mediated metabolic pathways of dimethylaniline in male rabbits.

Cadmium is an environmental pollutant and its effect on the in vitro metabolism of N,N-dimethylaniline (DMA) using male rabbits was investigated. Activities of cytochrome P-450 and FMO-dependent monooxygenases were studied using hepatic microsomes. Following CdCl2 (i.p.) administration (6 mg/kg/day for 6 days), both DMA-N-oxidation and DMA-N-demethylation decreased by 86%. The effects of CdCl2 on the phenobarbitone (PB)-induced form of P-450 were also studied. Intraperitoneal pretreatment of rabbits with PB (5 mg/kg/day for 5 days) increased N-demethylation by 82%, while N-oxidation decreased by 49%. Both reactions decreased significantly on additional treatment with CdCl2. Promethazine (5 mg/kg/day for 5 days) did not produce any change in the activities of either enzyme. The enzymes remained unaffected by CdCl2 treatment in promethazine-pretreated animals thus confirming its role as a hepatoprotective agent.

Aniline Compounds↗