Biomedical subjects

R Bajwa

Publications and source records attributed to R Bajwa.

7 recordsLinked to original sources

PubMed2004

Effects of growth hormone on leucine absorption, intestinal morphology, and ultrastructure of the goldish intestine.

The mechanisms whereby exogenous growth hormone modulates intestinal structure and function in fish were investigated. Goldfish (Carassius auratus) were fed commercial flake diet sprayed with recombinant carp growth hormone (cGH) daily for 1 month. Control animals received food sprayed with the vehicle. After 1 month of daily feedings, body mass and length were determined, and animals were sacrificed to study intestinal characteristics. Sections of foregut were removed after determination of total gut length for measurement of leucine uptake, histology, and epithelial ultrastructure. Oral administration of cGH for 1 month resulted in a 40% increase in body mass and an 8% increase in body length above controls. Gut length was 43% greater and the gut length to body length ratio was 32% greater as a result of the cGH treatment. Feeding with cGH also resulted in a significant increase in leucine uptake and increased gut mucosal thickness. Analysis of transmission electron micrographs revealed significant increases in the microvillous height and density and epithelial surface area. The findings indicate that growth hormone added to feed may increase growth in fish, in part by significantly increasing gut length, mucosal thickness, and epithelial brush border surface area, leading to enhanced epithelial absorption.

Animals↗

PubMed1998

Adenovirus-mediated delivery of rhodopsin-promoted bcl-2 results in a delay in photoreceptor cell death in the rd/rd mouse.

Gene transfer to retinal cells may provide a means to retard photoreceptor cell death and thus prevent blindness in diseases such as retinitis pigmentosa. We tested the possibility of interfering with apoptotic photoreceptor cell death in the rd mouse through subretinal delivery of a recombinant replication-defective adenovirus containing the human cDNA for bcl-2, Ad.2.5HRPbcl-2. Photoreceptor-specific transgene expression was accomplished through incorporation of the 2.5 kb human rhodopsin upstream fragment (HRP). Ad.2.5HRPbcl-2 was injected alone or in combination with Ad.CMVPDE beta. Ad.CMVPDE beta contains a cDNA encoding the beta subunit of cGMP phosphodiesterase (PDE beta). Recombinant viruses containing lacZ (driven either by the cytomegalovirus (CMV) promoter/enhancer or HRP) and of Ad.CMVPDE beta and vehicle alone were injected in contralateral eyes as control. Injection of Ad.2.5HRPbcl-2 in the rd mouse resulted in histologically detectable rescue lasting 6 weeks after birth. Extent of rescue was not as large as after delivery of wildtype PDE beta, the gene defective in the rd mouse. However, delivery of genes which prevent apoptotic cell death may have broad application to gene therapy of retinal degenerative diseases.

Adenoviridae↗

PubMed1996

Blood conservation in small adults undergoing valve surgery.

OBJECTIVES: A substantial reduction in transfusion requirements for cardiac surgical procedures has been reported. Many of these reports have been described in patients undergoing coronary artery bypass grafting. Patients suffering from rheumatic heart disease in India are usually small and also anemic. This study was conducted to assess blood conservation methods for cardiac valve surgery in this subset of patients. DESIGN: This was a prospective, randomized study. SETTING: The study was performed in a New Delhi tertiary care hospital, and the patients were referred from the northern states of India. PARTICIPANTS: One hundred fifty consecutive patients undergoing elective valve surgery using cardiopulmonary bypass were included. The mean age was 27.7 years and mean weight was 45.2 kg. INTERVENTIONS: The patients were divided into three groups of 50 each. Group 1 received autologous fresh blood donated before bypass, and both a cell saver and membrane oxygenator were used. The oxygenator contents at the end of perfusion were processed by cell saver. Group 2 patients were reinfused with autologous blood only, and group 3 was a control group. In groups 2 and 3, the blood that remained in the oxygenator at the conclusion of cardiopulmonary bypass was reinfused. A hematocrit of less than 25% was considered an indication for transfusion in the postoperative period. MEASUREMENTS AND MAIN RESULTS: The mean preoperative hematocrit was 35.5%. A mean of 361.1 mL of autologous blood was collected from group 1 and 303.3 mL from group 2. Group 1 required 15 units of bank blood, group 2, 90 units (p < 0.001), and group 3, 102 units (p < 0.001). Seventy-eight percent of group 1 patients did not receive any donor blood. There was no significant difference in chest tube drainage among the three groups. CONCLUSIONS: In this unique group of patients whose mean body weight was only 45 kg, autologous blood alone did not decrease blood bank requirements but when combined with a cell saver and membrane oxygenator greatly reduced the need for donor blood.

Adult↗

PubMed1994

Myocardial depressant effect of nitrous oxide after valve surgery.

We have studied the cardiovascular effects of 50% nitrous oxide after cardiopulmonary bypass in 14 patients undergoing valve surgery. All patients received morphine as the principal anaesthetic. Nitrous oxide administration for 5 min caused a decrease in mean arterial pressure from 82 +/- 10 to 71 +/- 12.7 mmHg (P < 0.001), cardiac index (2.8 +/- 0.5 to 2.4 +/- 0.5 litres min-1 m-2, P < 0.01), heart rate (104 +/- 17 to 99 +/- 18 beats min-1, P < 0.05), left ventricular stroke work index (29.4 +/- 8.1 to 22 +/- 8.7 gm-m beat-1 mm-1, P < 0.001), stroke volume (45.3 +/- 11.6 to 40 +/- 12.8 ml beat-1, P < 0.05) and an increase in pulmonary vascular resistance from 106.4 +/- 53.9 to 143.9 +/- 81.0 dynes s cm-5 (P < 0.01) and right atrial pressure (1.42 +/- 2.09 to 1.71 +/- 2.21 mmHg, P < 0.05). There was no change in systemic vascular resistance. When nitrous oxide was discontinued all the parameters started to recover within 3 min. Mean arterial pressure returned to control value in 5 min, but cardiac index and pulmonary vascular resistance returned to control value in 10 min. Our results suggest a direct myocardial depression and that the use of nitrous oxide is not recommended immediately after valve surgery and cardiopulmonary bypass.

Adult↗

PubMed1993

Colposcopy in the diagnosis of human papilloma virus infection, cervical intraepithelial neoplasia and invasive carcinoma.

Colposcopic diagnosis of 156 different lesions of the cervix was compared with histologic examination of the cervical punch biopsies. Colposcopy showed high degree of sensitivity and specificity (96% and 99.2%) in cases of carcinoma of the cervix. In cervical intraepithelial neoplasia (CIN) it showed a sensitivity of 82.8% and specificity of 49.6%, while in subclinical papilloma virus infection (SPI), it showed high degree of specificity (93.7%) but poor sensitivity (19.7%).

Colposcopy↗

PubMed1990

Purification and characterization of annexin proteins from bovine lung.

Calcium-dependent association with a detergent-extracted particulate fraction was used as the first step in the purification of a group of phospholipid binding proteins. Elution of the detergent-insoluble fraction with excess ethylene glycol bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA) resulted in the release of several soluble proteins, termed calcium-activated proteins or CAPs. In the present paper, we describe the simultaneous purification of these CAPs and characterize their interaction with phospholipid, actin, and calmodulin. Partial sequence analysis has identified the majority of the CAPs as members of the annexin family of calcium and phospholipid binding proteins. Two additional CAPs may be novel proteins, one of which appears to be an annexin protein. All CAPs demonstrated Ca2(+)-dependent binding to phosphatidylserine vesicles but did not bind to phosphatidylcholine vesicles. The majority of CAPs exhibited Ca2(+)-dependent binding to F-actin; however, only CAP-III affected the rate of conversion of G-actin to F-actin. The interaction of CAP-III and lipocortin-85 with F-actin resulted in a Ca2(+)-dependent increase in both light scattering and sedimentation of F-actin under comparatively low centrifugal force. In contrast, only lipocortin-85 caused the formation of F-actin bundles. Although all of the CAPs bound to a calmodulin affinity column in a Ca2(+)-dependent manner, attempts to demonstrate binding of CAPs to native calmodulin were unsuccessful. These studies therefore document the similar behavior of the CAPs toward phospholipid and calmodulin but clearly show that F-actin binding or bundling is not a general property of these proteins. The reported purification procedure should allow further comparative studies of these proteins.

Actins↗

PubMed1975

Cryo-labyrinthectomy for post-mastoidectomy vertigo.

A case of severe vertigo, following multiple operations for chronic suppurative otitis media is described. Sensitive nystagmus-producing spots in the mastoid cavity were treated by cryosurgery. Despite the absence of histological evidence of sensory epithelium or nerve endings, a good result was obtained.

Cryosurgery↗