A study of factors governing fluid filtration in the diabetic foot

Abstract. The effect of lowering the foot on the factors governing fluid filtration in the foot were studied in 12 male insulin-dependent diabetic subjects and 10 controls. Toe skin blood flow, measured by laser Doppler flowmetry, was significantly higher during dependency in the diabetic group. In the control subjects, the colloid osmotic pressure of venous blood sampled from the foot rose to 47·7 mmHg (range 45·1–53·8) after 50 min of foot dependency. In the diabetic group, colloid osmotic pressure failed to rise to the same extent (median 36·7 mmHg; range 28·6–43·0; P < 0·001). Capillary pressure, measured directly by the Landis microinjection technique, was significantly higher in the diabetic group (85·3±1·7 ( n = 6) vs. 92·2±4·6 cm H₂O ( n = 6); P < 0·007), as was foot swelling rate determined by mercury strain gauge plethysmography (0·069±0·022 vs. 0·099±0·025 ml min^-1 100ml^-1; P < 0·02). These results suggest an impairment of the oedema-preventing mechanisms in diabetic subjects which may contribute to the risks of ulceration in the diabetic foot.     

Hemorrhagic and nonhemorrhagic brain lesions: evaluation with 0.35-T fast MR imaging

Two fast magnetic resonance (MR) imaging techniques, advanced Fourier and partial-flip imaging, were used at 0.35 T to examine 21 patients with suspected intracranial lesions; the results were quantitatively compared with a conventional spin-echo study. Both of the fast MR techniques yielded a fourfold reduction in imaging time per section. The advanced Fourier sequence showed contrast that was identical to the conventional spin-echo study with signal-to-noise ratios of 58% and 57% for the first and second echoes, respectively. The partial-flip sequence showed a contrast of 109% and 57% for lesions versus substantia alba, and 107% and 78% for substantia grisea versus substantia alba relative to the first and second echoes of the conventional spin-echo study. The partial-flip sequence was particularly sensitive to magnetic susceptibility; this produced artifacts that may undermine the usefulness of partial flip for routine screening in certain parts of the brain. However, this susceptibility significantly improved the detection of intracranial hemorrhage when compared with the spin-echo sequence, particularly when combined with phase mapping of the partial-flip study.     

Role of pepsin in the development of indomethacin-induced antral ulceration in the rat

Aims: To examine the effects of a pepsin inhibitor, pepstatin-A, a long acting H₂-receptor blocker, loxtidine, exogenous pepsin and exogenous acid against indomethacin-induced antral ulceration in the rat. Results: Indomethacin (60 mg/kg s.c.) caused antral ulceration in fasted/re-fed rats over a period of 4 h. Ulceration was prevented in a dose-dependent manner by treatment with pepstatin-A (0.1–1 mg.kg hourly) or loxtidine (3 mg/kg) given orally. Acidified methylcellulose (1 mL hourly per os) enhanced damage and also prevented protection by loxtidine (3 mg/kg per os). The protection by pepstatin-A was not altered by treatment with acidified methylcellulose but was reversed by treatment with a 10-fold excess of pepsin. Conclusion: These studies suggest that mucosal degradation by pepsin, rather than direct damage by luminal acid, was the major factor in the development of indomethacin-induced antral ulceration in the rat.     

Importance of Dietary Fiber in Childhood

Dietary fiber has important health benefits in childhood, especially in promoting normal laxation. Currently, children consume amounts of dietary fiber that appear to be inadequate for optimal health promotion and disease prevention. It is prudent to recommend that children older than 2 years of age increase dietary fiber intake to an amount equal to or greater than their age + 5 g/day. According to the “age + 5” rule dietary fiber intake would increase from 8 g/day at age 3 years to 25 g/day by age 20 years. After age 20, dietary fiber levels of 25 to 35 g/day are recommended. Dietary fiber intake should be increased gradually in childhood by increasing consumption of a variety of fruits, vegetables, legumes, cereals, and other whole-grain products. Although very high fiber intake in childhood could have adverse effects, the potential health benefits of a moderate increase in dietary fiber substantially outweigh the possible risks, especially in highly industrialized countries such as the United States. A safe range of dietary fiber intake for children may be between age + 5 and age + 10 g/day. This range is considered safe even for children and adolescents with marginal intakes of some vitamins and minerals; should provide enough dietary fiber for normal laxation; and may provide enough added dietary fiber to help prevent chronic diseases.J Am Diet Assoc. 1995; 1140-1146, 1149.     

Nodular hyperplasia surrounding fibrolamellar carcinoma

We report a case of acetaminophen-induced liver necrosis in a 14-year-old girl. At autopsy, a 9 cm subcapsular nodule was present in the right lobe of the liver which showed distinct zonation: a central greyish white area of fibrolamellar carcinoma with a peripheral fleshy, tan-coloured rim ranging from 1 to 2 cm in thickness. This peripheral zone consisted of nodular, hyperplastic parenchyma resembling the changes seen in focal nodular hyperplasia, and stood out from the adjacent necrotic parenchyma. The sparing of this zone from the deleterious effects of acetaminophen provides indirect evidence of a predominantly arterial rather than portal blood supply to this region. The arterial supply was most probably derived from the tumour vasculature and may explain the parenchymal hyperplasia sometimes reported adjacent to a fibrolamellar carcinoma. Awareness of this phenomenon is essential when evaluating a needle biopsy, as sampling of this region may lead to a false negative diagnosis.