Biomedical subjects

P Reddy

Publications and source records attributed to P Reddy.

152 records · Page 9Linked to original sources

PubMedDate not supplied

Etiology of colonic strictures in South African black and Indian patients.

The etiology of colonic strictures in 263 South African black and Indian patients is presented. Nonmalignant lesions accounted for strictures in two-thirds of the patients and included amebiasis (27), tuberculosis (24), nonspecific colitis (30), ulcerative colitis/Crohn's colitis (11) and other lesions (36). Malignant lesions caused strictures in approximately a third of the black and Indian patients, which is higher than in other reported series in blacks. Accurate clinical diagnosis is difficult and early histologic confirmation is mandatory in order to institute rational management. Strictures of the right colon in the black population are more likely to be benign, except in younger patients. Left-sided colonic strictures have an equal chance of being benign or malignant, and early histologic confirmation is essential. The coexistence of an underlying malignant lesion in association with an inflammatory lesion in an endemic area should always be considered, particularly if it fails to respond to empirical therapy within a short period of time.

Black People↗

PubMedDate not supplied

Elective surgery for corrosive-induced gastric injury.

Gastric cicatrization is a well recognized late sequela of corrosive gastric injury, but the optimum timing and type of surgery for this complication are still unclear. Over a 7-year period (1988-1994) 34 patients underwent elective surgery for gastric lesions secondary to corrosive ingestion. A total of 18 (53%) patients had an associated esophageal stricture and presented with dysphagia, 15 (44%) patients had features of gastric outlet obstruction, 6 (18%) had diffuse gastric injury, and 28 (82%) had a segmental lesion. A tube jejunostomy was done in 23 (68%) patients to improve nutrition and resulted in a significant increase in weight and in the serum protein level after 8 weeks of tube feeding. Elective surgery was performed 3 to 24 months (average 7 months) after ingestion of the corrosive substance. Gastric resection was done in 20 (59%) patients and gastrojejunostomy (without vagotomy) in 11 (32%); at follow-up the latter group did not exhibit development of a stomal ulcer. In patients with an associated esophageal stricture, endoscopic dilatation was successful in 89% patients and simplified the surgical approach. In conclusion, the success of surgery for corrosive-induced gastric injury depends on selecting the right procedure and intervening at the appropriate time.

Acids↗

PubMedDate not supplied

Overproduction and rapid purification of the phosphoenolpyruvate:sugar phosphotransferase system proteins enzyme I, HPr, and Protein IIIGlc of Escherichia coli.

We present methods for the rapid, simple purification of Enzyme I, HPr, and Protein IIIGlc of the Escherichia coli phosphoenolpyruvate:sugar phosphotransferase system (PTS) using plasmids overproducing gene products. The gene for HPr (ptsH) was cloned into the expression vector pKC30. A simple procedure was devised for the purification to homogeneity of this protein from extracts of heat-induced cells containing pKC30/ptsH recombinant clone. The genes for Enzyme I (ptsI) and Protein IIIGlc (crr) were cloned separately into the expression vector pRE1. Rapid purification procedures were developed for the isolation of homogeneous preparations of these two proteins from extracts of heat-induced cells containing pRE1/ptsI and pRE1/crr recombinants. From about 6 g of cells, these procedures yielded 100, 86, and 50 mg of Enzyme I, HPr, and Protein IIIGlc, respectively. The activity of the proteins purified by these methods was comparable to that of the proteins isolated by previously published less efficient procedures.

Base Sequence↗

PubMedDate not supplied

Health care seeking behaviour of patients with sexually transmitted diseases: determinants of delay behaviour.

The study aimed to determine the factors associated with a delay in seeking health care for symptoms of sexually transmitted diseases (STDs) among a sample of 1482 patients attending STD clinics. Of the sample 78% were male, 58% sought help from the clinic within the first 6 days of noticing symptoms, 24% waited between 7 and 10 days and 17% waited longer than 10 days before seeking health care. Patients who delayed were those who treated themselves prior to seeking health care, who were female, whose friends waited before seeking treatment, who held misconceptions regarding the cause of STDs, who perceived STDs not to be serious and who valued personal autonomy in sexual behaviours less and had less positive outcome expectations of refusing sex. The data suggest that targeted interventions should be directed specifically at women and the youth. Early health care seeking could be facilitated through improved basic knowledge regarding STDs, control over one's own sexual behaviour and social support for early health care seeking.

Adult↗

PubMedDate not supplied

Effect of PDI overexpression on recombinant protein secretion in CHO cells.

In eukaryotic cells, protein disulfide isomerase (PDI) found in the endoplasmic reticulum (ER) catalyzes disulfide bond exchange and assists in protein folding of newly synthesized proteins. PDI also functions as a molecular chaperone and has been found associated with proteins in the ER. In addition, PDI functions as a subunit of two more complex enzyme systems: the prolyl-4-hydroxylase and the triacylglycerol transfer proteins. Increasing PDI activity in bacterial, yeast, and insect cell expression systems can lead to increased secretion of heterologous proteins containing disulfide bridges. Since Chinese hamster ovary (CHO) cells are widely used for the expression of recombinant proteins, we expressed recombinant human PDI (rhu PDI) in CHO cells to increase cellular PDI levels and examined its effect on the secretion of two different recombinant proteins: interleukin 15 (IL-15) and a tumor necrosis factor receptor:Fc fusion protein (TNFR:Fc). Secretion of TNFR:Fc (a disulfide-rich protein) is decreased in cells overexpressing PDI; the TNFR:Fc protein is retained inside these cells and colocalizes with the overexpressed rhu PDI protein in the endoplasmic reticulum. PDI overexpression did not result in intracellular retention of IL15. The nature of the interaction between PDI and TNFR:Fc was further investigated by expressing a disulfide isomerase mutant PDI in CHO cells to determine if the functional activity of PDI is involved in the cellular retention of TNFR:Fc protein.

Animals↗

PubMedDate not supplied

Cost and outcome analysis of home parenteral and enteral nutrition.

BACKGROUND: Previous estimates of the cost of home parenteral and enteral nutrition (HPEN) have excluded hospitalization costs or were conducted abroad and have limited applicability in the United States. Few studies have used validated measures to determine the effect of home nutrition support on quality of life. METHOD: A cost and clinical outcome analysis was performed by retrospective review of charts of patients receiving HPEN from 1991 to 1996. Questionnaires to determine the influence of therapy on lifestyle (n = 41) and a general health status questionnaire, the short form 36-item survey (n = 39), were mailed to patients. RESULTS: The annual cost per patient for parenteral solutions was $55,193 +/- 30,596 (mean +/- SD) based on Medicare charges and for enteral tube feedings was $9605 +/- 9327. The annual cost of hospitalization ranged from zero to $140,220 in the parenteral nutrition group and from zero to $39,204 in the enteral nutrition group. The annual number of hospitalizations per patient for patients receiving parenteral nutrition ranged from 0.52 to 1.10, compared with 0 to 0.50 in the enteral nutrition population. The health status of HPEN patients was significantly lower (p < .05) in five of the eight short-form 36 health domains compared with the general population. The areas of lifestyle most frequently affected were travel, sleep, exercise and leisure. CONCLUSIONS: The majority of the cost of therapy was associated with the direct provision of nutrition, although in some patients the hospitalization expenditure exceeded this cost. Home nutrition support had a significant negative impact on a patient's quality of life and lifestyle.

Adult↗

PubMedDate not supplied

Technique of cultivating limbal derived corneal epithelium on human amniotic membrane for clinical transplantation.

BACKGROUND: The technique of transplantation of cultivated limbal epithelium rather than direct limbal tissue isa novel method of "cell therapy" involved in reconstructing the ocular surface in severe limbal stem cell deficiency [LSCD], caused by chemical burns. AIM: To describe a simple feeder-cell free technique of cultivating limbal epithelium on human amniotic membrane[HAM]. MATERIALS AND METHODS: The limbal tissues (2 mm) were harvested from patients with LSCD. These tissues were proliferated in vitro on HAM supplemented by human corneal epithelial cell medium and autologous serum. Cultures covering more > or = 50% area of 2.5 x 5 cm HAM were considered adequate for clinical use. The cultured epithelium was characterized by histopathology and immunophenotyping. RESULTS: A total of 542 cultures out of 250 limbal tissues were cultivated in the laboratory from January 2001 through July 2005. The culture explants showed that clusters of cells emerging from the edge of the explants in one-three days formed a complete monolayer within 10-14 days. In 86% of cultures (464 of 542), the growth was observed within one-two days. Successful explant cultures were observed in 98.5% (534 of 542 cultures) with 91% explant cultures showing an area of > or = 6.25 cm2 (6.25 - 12.5 cm2 range). The cultivated epithelium was terminated between 10-14 days for clinical transplantation. The problems encountered were inadequate growth (2 of 542) and contamination (2 of 542). CONCLUSIONS: We demonstrate a simple technique of generating a sheet of corneal epithelium from a limbal biopsy. This new technique could pave the way for a novel form of cell therapy.

Amnion↗

PubMedDate not supplied

Protein kinase CK2 activities in human prostatic and seminal-vesicle secretions and seminal plasma.

Human prostatic secretion and seminal plasma contain certain protein kinase activities. Protein kinases play important roles in regulating a vast variety of cellular functions. The objective of this study was to determine whether one of these protein kinase activities in human prostatic secretion and seminal plasma is due to CK2, a messenger-independent, serine/threonine protein kinase that has considerable potential as a regulatory enzyme. By employing an anti-CK2 antibody and a CK2-specific peptide substrate, we have established that CK2 is present in these secretions. Approximately 70% of the CK2 activity present in seminal plasma of normozoospermic men (n = 49) is correlated to the number of sperm originally present in the semen. Further, both the prostate gland and the seminal vesicles are sources of CK2 activity in the seminal plasma of vasectomized men (n = 38). Although there was considerable variation between individuals in CK2 activity, the variation in repeat semen samples of the same vasectomized men (n = 6) was within 21%. There was no correlation of CK2 activity in seminal plasma with age for vasectomized (27-48 years, n = 38), oligozoospermic (28-43 years, n = 24), or normozoospermic men (26-48 years, n = 49). These data suggest that the majority of CK2 activity in the seminal plasma of normozoospermic men originates from sperm but that the prostate and seminal vesicles are accessory sex-gland sources of this enzyme.

Adult↗