Search PubMed⌕ Search

Biomedical subjects

B C Patel

Publications and source records attributed to B C Patel.

At least 55 records · Page 3Linked to original sources

Exogenous Nocardia asteroides endophthalmitis following cataract surgery.

We present a case of Nocardia asteroides endophthalmitis following cataract surgery. It is the second to be reported and the first in which vision has been preserved. Symptoms commenced 5 days after surgery and there followed a chronic relapsing anterior uveitis which lasted for 4 months. Nocardia asteroides was finally cultured from an aqueous aspirate and a combination of specific antimicrobial treatment and surgery resulted in a satisfactory visual outcome. Exogenous nocardial intraocular infection is rare and must be distinguished from fungal infection as the organism is resistant to antifungal agents.

Cataract Extraction↗

Infective endophthalmitis following vitreoretinal surgery.

Eleven cases of endophthalmitis occurring after vitreoretinal surgery are described. At Moorfields Hospital, London, from 1986 to 1990 the incidence of endophthalmitis after explant surgery with or without drain was 0.19% and after vitrectomy was 0.15%. We conclude that the parity may be due to the intraocular instrumentation of most conventional retinal detachment repair procedures. The best indicator of poor prognosis was speed of onset of symptoms, those with rapid evolution having the worst outcome; 2 of these cases were enucleated. Those presenting at 2-3 days had the best outcome, consistent with infection due to a less virulent organism. Delays in diagnosis were in part due to the posterior location of signs of infection. Potential risk factors amenable to prophylactic strategy were identified in 10 of the 11 patients. Supplementary prophylaxis using ciprofloxacin or imipenem is proposed for cases with an identifiable risk factor. After systemic administration these antibiotics achieve vitreous levels that exceed the MIC90 of the commonest causative pathogens.

Drainage↗

Anaerobic orbital abscess secondary to intraorbital wood.

A case of anaerobic orbital cellulitis secondary to intraorbital wood and an approach to management are presented. Retained foreign bodies should be suspected in all penetrating orbital injuries involving wood. Computed tomography (CT) should be performed to delineate the location and size of any foreign body and to determine damage to adjacent structures. Magnetic resonance imaging (MRI) is useful in certain circumstances. Orbital infection should be anticipated and broad-spectrum antibiotic cover (including anaerobes) provided. Surgical intervention should be undertaken to remove any retained foreign bodies to prevent vision-threatening complications.

Abscess↗

An experimental evaluation of precision laser cutting of dental hard tissues and materials.

This paper examines the use of excimer laser radiation in the controlled removal of tooth tissue and three plastic restorative materials. Freshly extracted human third molar teeth were filled with three restorative materials and sectioned longitudinally through the restoratives. The cut surfaces of the materials and surrounding enamel and dentine were exposed to three laser energy densities and the dimensions and topographical details of the irradiated sites assessed using optical and scanning electron microscopy. The results showed that the radiation produced lesions of uniformly reproducible size and shape.

Composite Resins↗

Acute tear of the retinal pigment epithelium.

The fluorescein angiographic findings immediately following a tear of the retinal pigment epithelium are presented and the mechanisms of fluid movement from the retina to the choroid are discussed. Our case represents a clinical correlate to recent experimental reports on fluid movement across the retinal pigment epithelium-Bruch's membrane complex.

Acute Disease↗

Biocompatibility assessment: application of fluorescent probe response (FPR) technique.

An in vitro test procedure capable of discriminating effectively between intact and membrane-damaged cells has been developed. This procedure utilizes fluorescein diacetate and ethidium bromide as fluorescent probes. The properties of the probes and the collapse in the selective cytoplasmic membrane permeability barrier of the damaged cells ensure the principal feature of the test procedure, that functional cells fluoresce bright green, but membrane-damaged cells fluoresce bright red. Investigations with natural rubber, silicone and acrylic polymers confirmed the suitability of the procedure to distinguish between materials on the basis of cytotoxicity.

Acrylic Resins↗

Work-related penetrating eye injuries.

A review of all penetrating eye injuries treated at the Manchester Royal Eye Hospital over 5 years (January 1st 1982 to December 31st 1986) was undertaken. There were 258 penetrating eye injuries of which 69 (26.7%) were due to work-related accidents. All were men and 52 (75.4%) of them were under the age of 40 years. Hammering and chiselling were the commonest activities at the time of the injury and accounted for 25 cases (36.2%). Thirty-six patient (52.1%) had intraocular foreign bodies. Thirty-six patients (52.1%) achieved a good visual result (6/12 or better) and 9 had no perception of light, 7 of whom had enucleations. The period of inpatient treatment ranged from 1 to 26 days. From the analysis of the activities at the time of the injury, 61 injuries (88.4%) may be considered to be preventable with appropriate eye protection.

Accidents, Occupational↗

Orbital xanthogranuloma in adults.

The onset of periorbital xanthogranuloma in adults is rare and may be accompanied by haematological abnormalities and malignancy. The appearance of the eyelid lesions is virtually diagnostic, producing readily recognisable diffuse, yellow plaques, and affected patients should be investigated and reviewed regularly for systemic disease. Three cases are described, in which periorbital cutaneous plaques were associated with abnormal tissues in the superior part of the orbit; these abnormal tissues caused displacement or restricted movement of the globe or upper eyelid. The possibility that two cases represent a necrobiotic type of xanthogranuloma is presented. Nine years after the onset of xanthogranuloma one patient developed non-Hodgkin's lymphoma. A multiple-drug regimen of systemic chemotherapy, given for lymphoma, caused a marked clinical reduction in the periorbital xanthogranuloma.

Adult↗

Impairment of hepatic insulin receptors during chronic ethanol administration.

Chronic alcoholism is frequently associated with impaired intermediary metabolism and insulin resistance. The cellular defects leading to insulin resistance have not been clearly defined but could result from reduced insulin binding or abnormalities in any one of several postreceptor steps. The purpose of the present studies was to measure 125I-insulin binding and internalization kinetics and postreceptor response of the enzyme activity of tyrosine aminotransferase in isolated cultured rat hepatocytes. Four weeks of alcohol ingestion significantly reduced to 47% of control the 125I-insulin binding sites measured either as surface or total (after digitonin permeabilization). In contrast, 125I-epidermal growth factor binding was not significantly changed. Internalization of surface-bound 125I-insulin was decreased, but degradation was not increased, indicating that altered kinetics did not account for the change. Ethanol ingestion markedly reduced in liver cytosol some enzymes regulated by insulin and involved in glucose homeostasis. Basal activities of tyrosine aminotransferase and glucokinase were reduced 51% (P less than 0.01) and 32% (P less than 0.01), respectively. In contrast, phosphoenolpyruvate carboxykinase was unchanged. In short-term cultured hepatocytes from ethanol-fed rats, the maximum response of tyrosine amino-transferase to insulin was reduced 40% (P less than 0.01) without a change in the concentration causing 50% of the maximum response (EC50) compared with controls. In contrast, dexamethasone increased tyrosine aminotransferase to similar maximal levels and with similar EC50, indicating that ethanol did not alter the intracellular response. In conclusion, chronic ethanol ingestion caused significant time-dependent and selective changes in cell surface binding of insulin that was associated with subsequent postreceptor events.

Animals↗

The use of focus groups in social and behavioural research: some methodological issues.

The use of focus groups as a qualitative method for rapid assessment is discussed. A focus-group session is an in-depth discussion in which a small number of people (usually 8-12) from the target population discuss topics that are of importance for a particular study or project. Generally the participants are chosen purposively, and it is recommended that they should be homogeneous with respect to characteristics which might otherwise impede the free flow of discussion. Focus groups can be used for idea generation, in conjunction with a quantitative method, or as a primary data-collection method. However, if focus groups are used as a primary data-collection method, their results must be treated with caution. The main advantage of using focus-group discussions during rapid assessment is that they provide in-depth information without requiring full-scale anthropological investigations. The informal group setting is believed to make people feel at ease, encouraging them to express their views freely. However, there are a number of limitations to focus-group discussions. The samples are small and purposively selected, and therefore do not allow generalization to larger populations. In addition, as with other qualitative methods, the chances of introducing bias and subjectivity into the interpretation of the data are high. There are a number of methodological issues which still need to be addressed in order to further develop the method. Little is known about how many discussion sessions are needed to be reasonably sure that most aspects related to the subject of inquiry have been explored.(ABSTRACT TRUNCATED AT 250 WORDS)

Data Collection↗