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Biomedical subjects

A Patel

Publications and source records attributed to A Patel.

At least 433 records · Page 24Linked to original sources
PubMed1990

Blood hyperviscosity and its relationship to progressive renal failure in patients with diabetic nephropathy.

Blood rheology was investigated in patients with diabetic nephropathy and progressive renal insufficiency, and compared with similar non-diabetic patients and healthy control subjects. Plasma viscosity and whole blood viscosity at standardized haematocrit were elevated to a comparable degree in the two patient groups, but erythrocyte deformability was normal. In diabetic patients, the rate of progression of renal failure showed weak, but significant, correlations with plasma viscosity (rs = 0.50, p = 0.005), standardized whole blood viscosity (rs = 0.41, p = 0.021), plasma fibrinogen (rs = 0.46, p = 0.010), C reactive protein (rs = 0.40, p = 0.023), and proteinuria (rs = 0.52, p = 0.003). Both plasma viscosity and plasma fibrinogen correlated significantly with proteinuria (rs = 0.45, p = 0.012 and 0.40, p = 0.027, respectively). Rheological abnormality is probably a manifestation of increased acute phase proteins, but it remains to be determined whether these are the cause or the effect of the renal injury. Abnormal blood rheology may be a risk factor for the progression of renal failure in diabetic nephropathy.

Adult↗
PubMed1990

Pharmacocavernometry in the assessment of erectile impotence.

Thirty-three impotent men underwent pharmacocavernometry and cavernography. Ten patients had a good clinical response to 60 mg papaverine, nine had a moderate clinical response and in 14, the response was judged to be a poor one. Twelve patients had evidence of abnormal venous leakage from the corpora. Subsequent investigation with isotope phallography showed six patients to have arterial insufficiency and in three of these patients this was amenable to reconstructive vascular surgery. We conclude that pharmacocavernometry provides a useful, cheap and reliable method for the investigation of impotent men which may be performed on an outpatient basis.

Adult↗
PubMed1990

Applications of a new chemiluminometric thyrotropin assay to subnormal measurement.

A new immunochemiluminometric TSH assay (ICMA) was shown to offer improved analytical (+2 SD of zero) and functional (20% interassay coefficient of variation) sensitivity [0.003 vs 0.045 +/- 0.005 (+/- SE; range, 0.01-0.07); 0.018 vs. 0.23 +/- 0.02 (range, 0.10-0.35, mU/L); analytical vs. functional sensitivity limit for the ICMA vs. 10 other TSH immunometric assays, respectively]. The ICMA was used to study the physiological relationship between serum TSH and free T4 [as reflected by free T4 index (FT4I)] values at both steady state and 14 days after acute pharmacological T4 administration (3 mg oral T4 load plus 0.3 mg daily). At steady state, an inverse log/linear relationship was found between serum TSH and FT4I values (log TSH = 2.56 - 0.022 FT4I; r = 0.84; P less than 0.001). Ten to 14 days after acute T4 suppression in 5 euthyroid subjects, serum TSH/FT4I levels had plateaued after decreasing in parallel to the slope of the steady state relationship, suggesting that the degree of T4 suppression of TSH can be predicted from an individual's pituitary TSH/free T4 set-point and the magnitude of the serum T4 elevation achieved. Ambulatory and hospitalized patient sera, previously identified as having low (less than 0.1 mU/L) TSH levels by a less sensitive assay, were restudied by the TSH ICMA. Normal TSH values ranged from 0.39-4.6 mU/L, whereas the majority of hyperthyroid patients [52 of 54 (96% ambulatory) and 22 of 23 (96%, hospitalized)] had undetectable (less than 0.005 mU/L), basal TSH levels and absent TRH stimulated TSH responses. In contrast, most (32 of 37; 86%) of hospitalized nonhyperthyroid patients with low (less than 0.1 mU/L) TSH values due to nonthyroidal illness or glucocorticoid treatment had detectable (greater than 0.01 mU/L) basal and TRH stimulated TSH levels. The positive relationship between basal and TRH-stimulated TSH levels was shown to extend down to the detectability limit of the assay (0.005 mU/L), which further supported the authenticity of the subnormal TSH ICMA measurements. The new TSH ICMA is considered to represent the first of a third generation of clinical TSH assays, since it has a functional (interassay) sensitivity that is 2 orders of magnitude greater than that of typical first generation TSH RIAs and 1 order of magnitude greater than current second generation TSH immunometric methods. Such third generation TSH assays will facilitate both the optimization of T4 therapy as well as the diagnosis of hyperthyroidism in hospitalized patients with nonthyroidal illness.

Adult↗
PubMed1990

Adrenal failure in fulminant meningococcal septicaemia: a clinical reality.

Current teaching is that adrenal failure is not a feature of meningococcal sepsis, and that cortisol levels are generally elevated. A case of fulminant meningococcal septicaemia in a 14-year-old boy is described. This patient had low/borderline cortisol levels, which normalised within some days.

Adolescent↗
PubMed1990

Pneumatosis intestinalis in AIDS: an unreported complication.

Pneumatosis intestinalis (PI) was first described by DuVernou in 1730. Since then, there have been reports of a benign form of PI occurring in both children and adults. Pneumatosis has been associated with a great many diseases, but to our knowledge there are no reports of pneumatosis in patients with acquired immune deficiency syndrome (AIDS). In this paper we report the incidental finding of PI in an AIDS patient. With ever-increasing numbers of AIDS patients, this entity may be seen more often, and clinicians should be aware of its clinical significance.

Acquired Immunodeficiency Syndrome↗
PubMed1990

Aetiology of diarrhoea in pre-term neonates at Kenyatta National Hospital nursery, Nairobi, Kenya.

The aetiology of two outbreaks of diarrhoea in pre-term neonates (March-August; September, 1987), at Kenyatta National Hospital was studied. The first outbreak involved 98 neonates and enteropathogenic E. coli of different serotypes were the most commonly isolated agents (54%), with serotype 086a:K61 dominating. These were followed by Salmonella (16%) also of different groups, and then rotavirus (6%). Two campylobacter and two Shigella were isolated from four individual neonates. Mixed infections were mainly those of Salmonella and E. coli (5 cases). E. coli serotype 086 was found to be in circulation throughout the study period (March-August, 1987), whilst 044:0125 and 0128 circulated for a limited period. Salmonella and some strains of E. coli caused persistent diarrhoea despite antibiotic therapy. Nosocomial infections were found to play a role in subsequent diarrhoeas. In the second diarrhoea outbreak, again enteropathogenic E. coli and Salmonella were the most frequently isolated. However, in this outbreak, there was no single E. coli serotype revealed that some possessed plasmids of 120-160 megadalton. However, a search for human immunodeficiency viral antibodies in 120 stools produced negative results.

Cross Infection↗
PubMed1990

Haemostatic changes in the loin pain and haematuria syndrome: secondary to renal vasospasm?

Twenty-five patients (seven male, 18 female) were diagnosed as having the loin pain and haematuria syndrome. Presenting symptoms were either loin pain alone or pain associated with macroscopic or microscopic haematuria, and were longstanding, having been present for mean of 9.3 years in males, and 10 years in females. Ten patients described symptoms of passing gravel or renal stones but these were only demonstrated radiologically in two patients. Investigation of all patients showed anatomically normal renal tracts, normal renal function, and no significant proteinuria. Phase-contrast microscopy during episodes of haematuria revealed dysmorphic red cells in all 10 patients studied. Renal biopsies were performed in 20 patients and showed no glomerular pathology, but arteriolar and arterial hyalinosis was seen in 13 of 20 (65 per cent), fibro-elastosis in larger vessels in eight of 20 (40 per cent) and red blood cells in tubules in 13 of 20 (65 per cent) patients. The histological appearance in vessels was similar to that seen in cyclosporin A nephrotoxicity and would be consistent with the hypothesis that regional vasospasm occurs in the cortical circulation. Haematological studies in 22 patients, when compared with age and sex matched controls, showed the presence of circulating platelet aggregates, elevation of plasma beta-thromboglobulin (p less than 0.001), and increased platelet aggregation in response to serotonin and ADP (p less than 0.05 and p less than 0.03, respectively). Plasma concentrations of D dimer (p less than 0.02) and C-reactive protein (p less than 0.03) were also significantly elevated in the patient group. There was no deterioration of renal function during a mean observation period of 3.7 years and no patients developed proteinuria. Treatment was largely supportive; seven patients with intractable loin pain underwent surgical denervation with the relief of pain in four.

Adult↗
PubMed1989

Ultrasonography and scintigraphy in liver disease in developing countries. A retrospective survey.

In a study of the value of hepatic ultrasonography (US) and scintigraphy (SG) in detecting liver disease in developing countries 425 US scans and 304 SG scans of patients with focal or diffuse liver disease or normal livers were reviewed. The accuracy of both US and SG in distinguishing between normal and diseased livers was low (68% and 74%, respectively). Both techniques did better at detecting focal than diffuse liver disease; the sensitivity of US and SG in focal and diffuse disease was 88% and 92%, and 27% and 54%, respectively. The specificity of both procedures was high for both types of liver disease (91-96%). Overlap between US features of amoebic liver abscess, hepatocellular carcinoma, and metastatic carcinoma resulted in a correct final diagnosis being made in only 81% of patients with amoebic liver abscess, 29% with hepatocellular carcinoma, and 43% of patients with metastatic carcinoma who had a US scan. This study indicates that these techniques are neither accurate in detecting diffuse liver disease nor capable of determining the cause of diffuse liver disease. When diffuse parenchymal liver disease is suspected biopsy would be needed. Although the accuracy of both imaging modalities in detecting focal disease is high, overlap between the US features of the common causes of space-occupying lesions may result in an incorrect final diagnosis in some cases. In consequence, biopsy or aspiration might be required.

Biopsy↗
PubMed1989

Indications for aspiration of amoebic liver abscess.

A two-part study was undertaken to determine whether aspiration of amoebic liver abscess (ALA) prevents complications. Eighty patients studied prospectively were randomised into aspiration or non-aspiration groups and were treated with metronidazole. Common factors in patients with complicated diseases were determined to formulate and test indications for aspiration. Records of all patients with ALA admitted to King Edward VIII Hospital, Durban, between October 1983 and December 1984 were analysed to test the validity of the criteria derived from the first part of the study. The findings suggest that aspiration influences the course and outcome of ALA and that the criteria are valid although not necessarily complete.

Evaluation Studies as Topic↗
PubMed1989

The conformation of dolichol.

An understanding of the natural conformation of dolichol is important for the elucidation of the mechanism of protein glycosylation and dolichol's other as yet undisclosed biological functions. Since the molecular mechanics method has been shown to be well suited for the prediction of alcohol and alkene conformations, we have employed it to study the conformations of apparent least energy of dolichol-19 and smaller polymers of isoprene, namely, squalene, trans,trans-farnesol, and cis,cis-farnesol. Additionally, the small-angle X-ray scattering (SAXS) method was employed to determine the validity of the apparent least energy conformer of dolichol-19 derived by the molecular mechanics method. The results indicate that the solution conformation of dolichol-19 is comprised of a central coiled region flanked by two arms. The central coiled region has two and a half turns of dimensions 9.84 x 16.55 x 51.66 A3. The arms of dimensions 3.99 x 5.89 x 17.47 A3 and 4.49 x 9.23 x 11.14 A3 are approximately diametrically opposed. Measurement of the intrinsic viscosity of dolichol in both isopentyl alcohol and oleyl alcohol showed that the natural conformation of dolichol is capable of increasing solution fluidity (i.e., lowering solution viscosity). Thus, while examination of the conformation of dolichol in a membrane-mimetic solvent by SAXS is not possible, the quantitative measure of the effect of dolichol on solution viscosity (and thus solution fluidity) is possible. The results are consistent with dolichol acting as a membrane-fluidizing agent and provide the first quantitative measure of the effect of dolichol on solution fluidity of a membrane-mimetic solvent.

Dolichols↗
PubMed1989

Right ventricular free wall ischemia: correlation of ischemic duration with extent of infarction in dogs.

The time dependence of myocardial necrosis has not been established for the right ventricle. In 16 dogs, we studied the temporal extension of ischemia-induced right ventricular free wall infarction for one hour (n = 8) and two hours (n = 8) followed by two hours of reperfusion, and quantitated segmental shortening, area at risk from ischemia, and area of necrosis. Stroke volume decreased 7.3 +/- 0.5 mL/beat (+/- standard error of the mean) in one hour (p less than 0.05) and 7.4 +/- 1.3 mL/beat in two hours (p less than 0.05). Segmental shortening was replaced by paradoxical motion in both groups during ischemia, and remained depressed throughout reperfusion. Right ventricular end-diastolic pressure increased with ischemia and then returned to normal during reperfusion. The extent of infarction appeared proportionate to the duration of ischemia, 13.2% +/- 4.1% at one hour and 66.9% +/- 4.5% at two hours (p less than 0.01). We conclude that the wave front of necrosis in the right ventricle progresses with duration of ischemia and that clinical techniques capable of limiting the duration of ischemia might salvage substantial amounts of right ventricular myocardium.

Animals↗