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1.
Suppurative corneal ulceration in Bangladesh 总被引:8,自引:0,他引:8
AAS Dunlop MB BS ED Wright MRCPath † SA Howlader‡ I Nazrul‡ R Husain‡ K McClellan FRACO § FA Billson FRACO § 《Clinical & experimental ophthalmology》1994,22(2):105-110
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. 相似文献
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Nonheme iron in sickle erythrocyte membranes: association with phospholipids and potential role in lipid peroxidation 总被引:5,自引:0,他引:5
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. 相似文献
5.
G Waterman J D Epstein N A Fenske 《Cutis; cutaneous medicine for the practitioner》1989,43(3):262-263
In most cases, herpes zoster (shingles) infections are benign and self-limited, requiring no treatment. However, if patients are elderly or immuno-compromised, they are at increased risk of complications such as visceral dissemination, cranial and nerve palsies, ophthalmic zoster, and postherpetic neuralgia. We present a case of herpes zoster infection complicated by both motor and sensory involvement in an elderly man. 相似文献
6.
Treatment of rats with methylandrostenediol (MAD), an anabolic androgen, caused a profound reduction (65%) in the level of cytochrome P-450 11 beta in rat adrenocortical mitochondria as measured by immunoblots using a specific antibody. The decreases in mitochondrial cytochrome P-450scc (15%) and adrenodoxin (20%) were much less than that observed for cytochrome P-45011 beta. A 35% decrease in adrenal microsomal cytochrome P-450 21 and NADPH-cytochrome P-450 reductase levels was brought about by the treatment with MAD. The data establish that the preferential decrease in adrenal steroid 11 beta-hydroxylase activity associated with androgen treatment results from a decrease in cytochrome P-450 11 beta. This is consistent with the role of 11-deoxycorticosterone in the pathogenesis of androgen-induced hypertension in rats. 相似文献
7.
R W Pinner B G Gellin W F Bibb C N Baker R Weaver S B Hunter S H Waterman L F Mocca C E Frasch C V Broome 《The Journal of infectious diseases》1991,164(2):368-374
Active surveillance for invasive meningococcal disease was conducted during 1986 and 1987 in six areas of the United States with a total population of approximately 34 million persons. The incidence of meningococcal disease was 1.3:10(5). The highest incidence of disease among the surveillance areas was in Los Angeles County (1.65:10(5). Neisseria meningitidis serogroups B and C caused about equal amounts of disease, which reflects a recent increase in the incidence of group C disease. Group C caused more than half of the cases of meningococcal disease in Los Angeles and Tennessee but less than one-third of the cases in Missouri and Oklahoma. Multilocus enzyme electrophoresis demonstrated that a group of closely related isolates of N. meningitidis was prevalent in Los Angeles during the surveillance period and was associated with an increased incidence of meningococcal disease there. 相似文献
8.
A E Kyles A Waterman A Livingston 《Journal of pharmacological and toxicological methods》1992,27(3):177-183
This paper describes a relatively simple and noninvasive method for the chronic implantation of intrathecal catheters in the sheep. The technique has been carried out on 17 occasions in nine sheep, with 60% of attempted catheterizations producing a correctly positioned, functional catheter. The placement and integrity of the catheters were confirmed by radiography using a contrast medium. Correctly placed catheters have been maintained for up to 16 months without problems. 相似文献
9.
Do commonly used oral antihypertensives alter fetal or neonatal heart rate characteristics? A systematic review. 总被引:1,自引:0,他引:1
E J Waterman L A Magee K I Lim A Skoll D Rurak P von Dadelszen 《Hypertension in pregnancy》2004,23(2):155-169
OBJECTIVE: To examine fetal (FHR) and neonatal heart rate patterns following use of common oral antihypertensives in pregnancy. METHODS: A systematic review of randomized controlled trials (RCTs), observational studies (N >/= 6 women), and animal studies. Data were abstracted (two reviewers) to determine relative risk (RR) (or risk difference (RD) for low event rates) and 95% CI. RESULTS: Eighteen RCTs (1858 women), one controlled observational study (N = 22), and seven case series (N = 117) were reviewed. Most hypertension was pregnancy-induced (N = 14 studies). The FHR was assessed by cardiotocogram (CTG) (N = 17 studies (visual interpretation); 1 study (computerized CTG), or umbilical artery velocimetry (N = 4). Four studies examined neonatal heart rate. In placebo-controlled RCTs (N = 192 women), adverse FHR effects did not differ between groups [9/101 (drugs) vs. 7/91 (placebo); RD 0.02, 95% CI (- 0.06, 0.11); chi2 = 1.02]. In six drug vs. drug RCTs (295 women), adverse FHR effects did not differ between groups [29/144 (methyldopa) vs. 42/151 (other drugs); RR 0.72, 95% CI (0.49, 1.07); chi2 = 0.69]. In one labetalol vs. placebo trial, neonatal bradycardia did not differ between groups [4/70 (labetalol) vs. 4/74 (placebo); OR 1.06, 95% CI (0.26, 4.39)], while in three drug vs. drug RCTs, neonatal bradycardia was not observed (0/24 vs. 0/26). CONCLUSIONS: Available data are inadequate to conclude whether oral methyldopa, labetalol, nifedipine, or hydralazine adversely affect fetal or neonatal heart rate and pattern. Until definitive data are available, FHR changes cannot be reliably attributed to drug effect, but may be due to progression of the underlying maternal or placental disease. 相似文献
10.
Anucha Apisarnthanarak Marilyn Jones Brian M Waterman Cathy M Carroll Robert Bernardi Victoria J Fraser 《Infection control and hospital epidemiology》2003,24(1):31-36
OBJECTIVE: To characterize risk factors for surgical-site infection after spinal surgery. DESIGN: A case-control study. SETTING: A 113-bed community hospital. METHOD: From January 1998 through June 2000, the incidence of surgical-site infection in patients undergoing laminectomy, spinal fusion surgery, or both increased at community hospital A. We compared 13 patients who acquired surgical-site infections after laminectomy, spinal fusion surgery, or both with 47 patients who were operated on during the same time period but did not acquire a surgical-site infection. Information collected included demographics, risk factors, personnel involved in the operations, length of hospital stay, and hospital costs. RESULTS: Of 13 case-patients, 9 (69%) were obese, 9 (69%) had spinal compression, 5 (38.5%) had a history of tobacco use, and 4 (31%) had diabetes. Oxacillin-sensitive Staphylococcus aureus (6 of 13; 46%) was the most common organism isolated. Significant risk factors for postoperative spinal surgical-site infection were dural tear during the surgical procedure and the use of glue to cement the dural patch (3 of 13 [23%] vs 1 of 47 [2.1%]; P = .02) and American Society of Anesthesiologists risk class of 3 or more (6 of 13 [46.2%] vs 7 of 47 [15%]; P = .02). Case-patients were more likely to have prolonged length of stay (median, 16 vs 4 days; P< .001). The average excess length of stay was 11 days and the excess cost per case was $12,477. CONCLUSION: Dural tear and the use of glue should be evaluated as potential risk factors for spinal surgical-site infection. Systematic observation for potential lapses in sterile technique and surgical processes that may increase the risk of infection may help prevent spinal surgical-site infection. 相似文献