Biomedical subjects

J Matharu

Publications and source records attributed to J Matharu.

3 recordsLinked to original sources

PubMed2001

Caloxin: a novel plasma membrane Ca2+ pump inhibitor.

Plasma membrane (PM) Ca2+ pump is a Ca+-Mg2+-ATPase that expels Ca2+ from cells to help them maintain low concentrations of cytosolic Ca2+ . There are no known extracellularly acting PM Ca2+ pump inhibitors, as digoxin and ouabain are for Na+ pump. In analogy with digoxin, we define caloxins as extracellular PM Ca2+ pump inhibitors and describe caloxin 2A1. Caloxin 2A1 is a peptide obtained by screening a random peptide phage display library for binding to the second extracellular domain (residues 401-413) sequence of PM Ca2+ pump isoform 1b. Caloxin 2A1 inhibits Ca2+-Mg2+-ATPase in human erythrocyte leaky ghosts, but it does not affect basal Mg2+-ATPase or Na+-K+-ATPase in the ghosts or Ca2+-Mg2+-ATPase in the skeletal muscle sarcoplasmic reticulum. Caloxin 2A1 also inhibits Ca2+-dependent formation of the 140-kDa acid-stable acylphosphate, which is a partial reaction of this enzyme. Consistent with inhibition of the PM Ca2+ pump in vascular endothelium, caloxin 2A1 produces an endothelium-dependent relaxation that is reversed by N(G)-nitro-L-arginine methyl ester. Thus caloxin 2A1 is a novel PM Ca2+ pump inhibitor selected for binding to an extracellular domain.

Adenosine Triphosphate↗

PubMed1992

Infective endocarditis in a district general hospital.

Thirty-three cases of infective endocarditis presenting during a 6.5 year period to a district general hospital were analysed retrospectively. The annual incidence was 22 cases per million population. Twenty-two cases had pre-existing cardiac disease, mainly valvular disease-usually rheumatic (nine cases) and prosthetic valves (10 cases). Recognizable precipitants such as recent surgery were uncommon. Two cases presented after deliberate drug overdose possibly due to depression exacerbated by systemic disease. Symptoms were usually non-specific. All but two cases had murmurs and most were pyrexial. Splinter haemorrhages and clubbing were seen in about 20% of cases. Viridans-type streptococci were the commonest infecting organisms (14 cases). Staphylococcal infection (six cases) was confined to intravenous drug abusers and patients with prosthetic valves. Five cases were culture negative. Cardiac failure was present in 13 cases at presentation and developed in seven others during treatment. Acute valve replacement was necessary in eight cases, and late replacement in three. Renal impairment (plasma urea > 8 mmol/l and/or plasma creatinine > 120 mumol/l) occurred in 19 cases during the course of their illness. Embolic phenomena occurred in 12 patients and mostly involved the central nervous system. In the 8 fatal cases, the cause of death was cardiac failure in six, cerebrovascular accident in one, and myocardial infarction in one. Four of the six patients who subsequently died of cardiac failure had been referred for surgery. Both those who were not referred had coexisting medical problems. Factors associated with increased mortality were age, male sex, cardiac failure (P < 0.01), renal impairment (P < 0.05), and embolic phenomena (P < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1988

Peritoneal papillary carcinoma.

Between 1977 and 1986, 325 patients with a diagnosis of ovarian carcinoma, peritoneal cancer, or malignant mesothelioma were reviewed with identification of 23 patients (7%) having peritoneal papillary cancer. Only 2 patients had disease confined to the pelvis and the rest had widespread abdominal disease. Various combination chemotherapeutic agents were used with over a 65% response rate to first-line chemotherapy. Twenty of the 23 patients received cisplatin combination chemotherapy with an overall response rate of 65%.

Adolescent↗