Suppurative corneal ulceration in Bangladesh

Suppurative keratitis is an important preventable cause of blindness, particularly in the developing world. This study analyses 142 cases of suppurative keratitis referred to Chittagong Eye Infirmary, Bangladesh. Some 53.5% of cases were bacterial and 35.9% were fungal. The five most common pathogens were: Pseudomonas sp. 24%, Streptococcus pneumoniae 17%, Aspergillus sp. 13%, Fusarium sp. 7% and Curvularia sp. 6%. Gram stain and culture results were consistent in 62.6% of cases. Previous antibiotic treatment was a significant factor for failure of culture isolation and less so for Gram stain failure. On Gram stain, 55.9% of pseudomonal cases were missed, but only 2% of fungal cases were missed. Over all, Gram stain had a sensitivity of 62% and positive predictive value of 84% for bacterial cases, and 98% and 94% for fungal cases, respectively. Fungal ulcers were typically filamentous, but an antecedent history of trauma was not common. The most frequent injury was due to rice grains, but the inoculum appeared to be introduced during eye washing with contaminated water. Pseudomonal ulcers occurred most frequently in the monsoon season, and Fusarium cases were seen only in the hot, dry season.     

Nonheme iron in sickle erythrocyte membranes: association with phospholipids and potential role in lipid peroxidation

Previous studies documented the abnormal association of heme and heme proteins with the sickle RBC membrane. We have now examined RBC ghosts and inside-out membranes (IOM) for the presence of nonheme iron as detected by its formation of a colored complex with ferrozine. Sickle ghosts have 33.8 +/- 18.2 nmol nonheme iron/mg membrane protein, and sickle IOM have 4.3 +/- 3.0 nmol/mg. In contrast, normal RBC ghosts and IOM have no detectable nonheme iron. The combination of heme and nonheme iron in sickle IOM averages nine times the amount of membrane- associated iron in normal IOM. Kinetics of the ferrozine reaction show that some of this nonheme iron on IOM reacts slowly and is probably in the form of ferritin, but most (72% +/- 18%) reacts rapidly and is in the form of some other biologic chelate. The latter iron compartment is removed by deferoxamine and by treatment of IOM with phospholipase D, which suggests that it represents an abnormal association of iron with polar head groups of aminophospholipids. The biologic feasibility of such a chelate was demonstrated by using an admixture of iron with model liposomes. Even in the presence of tenfold excess adenosine diphosphate, iron partitions readily into phosphatidylserine liposomes; there is no detectable association with phosphatidylcholine liposomes. To examine the bioavailability of membrane iron, we admixed membranes and t-butylhydroperoxide and found that sickle membranes show a tenfold greater peroxidation response than do normal membranes. This is not due simply to a deficiency of vitamin E, and this is profoundly inhibited by deferoxamine. Thus, while thiol oxidation in sickle membranes previously was shown to correlate with heme iron, the present data suggest that lipid peroxidation is related to nonheme iron. In control studies, we did not find this pathologic association of nonferritin, nonheme iron with IOM prepared from sickle trait, high-reticulocyte, postsplenectomy, or iron-overloaded individuals. These data provide additional support for the concept that iron decompartmentalization is a characteristic of sickle RBCs.     

Esophagogastric decompression and enteral feeding following cholecystectomy: a controlled, randomized prospective trial

One hundred fourteen patients scheduled to undergo elective cholecystectomy were prospectively randomized into one of four treatment groups to study the potential benefits of esophagogastric decompression with and without immediate postoperative enteral nutrition. Group I was the control, and patients received only iv fluids and were allowed to eat as tolerated. Group II patients received iv fluids and esophagogastric decompression. Group III patients received esophagogastric decompression and enteral sterile water through the duodenal feeding lumen. Group IV patients received esophagogastric decompression and infusion of an elemental diet through the feeding lumen. The surgical techniques were standardized for all patients. The results of the study indicated no statistically or clinically significant differences among any of the treatment groups regarding; (1) need for parenteral analgesics or antiemetics, (2) tolerance of regular diet, (3) postoperative day of discharge, and (4) postoperative day that other discharge criteria were met. It is concluded that there is no objective benefit to the routine use of esophagogastric decompression with or without enteral nutrition in elective cholecystectomy patients.     

Serum ionic fluoride levels in haemodialysis and continuous ambulatory peritoneal dialysis patients

High serum fluoride (F-) in patients with chronic renal failure (CRF) and end-stage renal disease (ESRD) is associated with risk of renal osteodystrophy and other bone changes. This study was done to determine F- in normal healthy controls and patients with ESRD on haemodialysis (HD) or peritoneal dialysis (PD). Seventeen healthy controls (12 males, 5 females) and 39 ESRD patients on dialysis (17 males, 22 females) were recruited in the study in a community with 47.4 +/- 3.28 microM/l (range 44-51 microM/l) of F- content in drinking water. Control subjects showed a mean serum F- concentration of 1.08 +/- 0.350 microM/l. Males in control group showed slightly higher F- levels (1.15 +/- 0.334, range 0.55-1.9 microM/l) than females (0.92 +/- 0.370, range 0.6-1.5 microM/l). Mean serum F- concentration did not correlate significantly with age and sex among control subjects, whereas such correlation was observed in patients with ESRD on dialysis. Mean serum F- concentration was significantly higher in patients on dialysis (2.67 +/- 1.09, range 0.8-5.2 microM/l) than normal controls. When grouped according to sex, the mean serum F- concentration in males (3.05 +/- 1.04, range 1.8-5.2 microM/l) was significantly higher than females (2.38 +/- 1.08, range 0.8-5.2 microM/l). When patients were grouped according to age, it was observed that F- concentration was significantly higher in patients with age groups 21-70 (2.86 +/- 1.05) than those with age group 13-20 years (1.42 +/- 0.531). Thus F- concentration correlated with age and sex, being higher in males and above 20 years. Despite appreciable clearance of F- (39-90%) across the peritoneum, patients on CAPD showed higher serum F- concentration than those on HD (3.1 +/- 1.97 vs 2.5 +/- 1.137 microM/l). Of the total 39 patients on dialysis 39% had their serum F- concentration above 3.0 microM/l, posing the risk of renal osteodystrophy.      

Functional changes in canine saphenous veins after cryopreservation.

This study was designed to determine the functional characteristics of the endothelium, smooth muscle and nerve terminals of cryopreserved veins. Freshly harvested and cryopreserved canine saphenous veins were cut into rings. In some rings, the endothelium was removed. Cryopreserved veins were stored at -196 degrees C for at least 3 weeks prior to use. All rings contracted in a concentration-dependent manner to depolarization with KCl and to alpha-adrenergic stimulation; the maximal tensions were significantly less in cryopreserved than in freshly harvested veins. Calcium ionophore A23187 caused greater relaxations in rings with than without endothelium in freshly harvested and cryopreserved veins. These relaxations were reduced significantly by methylene blue and NG-monomethyl-L-arginine (L-NMMA) only in fresh veins. Cocaine-sensitive uptake of H3-norepinephrine was reduced following cryopreservation. Immediately after cryopreservation, the production of prostacyclin was elevated. The calcium ionophore A23187 stimulated production of prostacyclin only in freshly harvested veins. Tissue content of endothelin did not change following cryopreservation. These results suggest that cryopreservation of canine saphenous veins alters nerve terminals and decreases the ability of the smooth muscle to contract. The endothelium releases an endothelium-derived relaxing factor and prostanoids following cryopreservation but the ability to synthesize nitric oxide is probably reduced. These changes following cryopreservation may affect patency of the veins when used as arterial grafts.     

新疆家畜蠕形蚤病病原研究

本文详细介绍了在新疆发现的花蠕形蚤、叶氏蠕形蚤、北山羊蠕形蚤、羊长喙蚤和狍长喙蚤的形态学特点、地理分布和某些生物学特性。