Cimetidine and malabsorption of cobalamin

Cimetidine in a dosage of 1000 mg daily (200 mg t.i.d. plus 400 mg nocte) reduced the absorption of protein-bound cobalamin by peptic ulcer patients and normal subjects. However, cimetidine in a dosage of 400 mg at night had no significant effect, nor did tripotassium dicitratobismuthate in a dosage of 480 mg daily. Thus long-term administration of 400 mg cimetidine at night will not produce cobalamin deficiency in man.     

Botulinum toxin: a case study.

A variety of therapeutic options exist for the treatment of achalasia. This case study explores these options and follows an individual's experiences as he undergoes these treatments from a barium swallow to botulinum toxin injection.     

Major Neurological Disease and Occupational Exposure to Organic Solvents

Five patients are described who presented with major organicbrain disease affecting one or more of pyramidal and extrapyramidaltracts, cerebellum, and higher cortical functions. All had ahistory of 10 years or more of regular occupational exposureto solvents in confined spaces, three in painting inside shipsand the others in weapons maintenance and printing. All hadbeen regularly exposed to high air vapour peaks as well as toskin contamination. Four showed some evidence of improvementafter the exposure ceased. None was initially suspected of havinga toxic encephalopathy by the consultant to whom he was referred.The spectrum of neurological disease presented by these menmirrors closely that described in solvent abusers. All wereforced by illness to retire from their work, a circumstancewhich might have in the past have led to such conditions beingmissed in cross-sectional studies, which in general have notshown evidence of major disease. We suggest that when such diseaseoccurs nowadays, its cause is usually not suspected. Furtherepidemiological study of the problem is necessary.     

Diverticulite solitaire du c?lon droit

Diverticula of the right colon are a rare clinical entity. Diverticulitis can occur with these lesions, but the diagnosis is frequently missed as the presentation is similar to that of acute appendicitis and can mimic other acute intraabdominal infections such as cholecystitis. The authors report a case of solitary diverticulitis of the right colon in a young woman, an incidental discovery during surgery for suspected appendicitis, with emphasis on the diagnostic and therapeutic modalities.     

Leaf palmate venation and vascular redundancy confer tolerance of hydraulic disruption

Leaf venation is a showcase of plant diversity, ranging from the grid-like network in grasses, to a wide variety of dendritic systems in other angiosperms. A principal function of the venation is to deliver water; however, a hydraulic significance has never been demonstrated for contrasting major venation architectures, including the most basic dichotomy, "pinnate" and "palmate" systems. We hypothesized that vascular redundancy confers tolerance of vein breakage such as would occur during mechanical or insect damage. We subjected leaves of woody angiosperms of contrasting venation architecture to severing treatments in vivo, and, after wounds healed, made detailed measurements of physiological performance relative to control leaves. When the midrib was severed near the leaf base, the pinnately veined leaves declined strongly in leaf hydraulic conductance, stomatal conductance, and photosynthetic rate, whereas palmately veined leaves were minimally affected. Across all of the species examined, a higher density of primary veins predicted tolerance of midrib damage. This benefit for palmate venation is consistent with its repeated evolution and its biogeographic and habitat distribution. All leaves tested showed complete tolerance of damage to second- and higher-order veins, demonstrating that the parallel flow paths provided by the redundant, reticulate minor vein network protect the leaf from the impact of hydraulic disruption. These findings point to a hydraulic explanation for the diversification of low-order vein architecture and the commonness of reticulate, hierarchical leaf venation. These structures suggest roles for both economic constraints and risk tolerance in shaping leaf morphology during 130 million years of flowering plant evolution.