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Biomedical subjects

D Narayan

Publications and source records attributed to D Narayan.

16 recordsLinked to original sources
PubMed2003

Multiple clinical manifestation of HTLV1 infection in a single patient.

HTLV-1 infection is endemic in the Caribbean and several publications have reported the clinical disease entities seen in this population of patients. This case report is an account of a patient admitted to Kingstown General Hospital, St Vincent and the Grenadines, who had severe infective dermatitis, tropical spastic paraparesis (TSP) and Non-Hodgkin's Lymphoma (NHL). As far as we are aware, all three diseases have not been described in a single patient.

Adult↗
PubMed2001

Surgical considerations in the management of malignant melanoma of the ear.

Malignant melanomas of the external ear are rare and are difficult lesions to treat because of the cosmetic importance and the reconstructive difficulty of their location. The literature suggests that these lesions have a worse prognosis than melanomas occurring elsewhere and that radical resection is the "correct" treatment. To clarify this issue, we examined 21 consecutive patients (19 male, 2 female) with malignant melanoma of the ear seen at the Yale-New Haven Hospital over the last 10 years. Nineteen patients had a diagnosis of primary malignant melanoma of the ear, one had a local recurrence, and one had an in-transit melanoma from an unknown primary site. The mean thickness of the lesions was 2.7 mm. Two patients had palpable nodes, which in both cases turned out to be histologically positive for tumor. All patients underwent local excision and reconstruction using chondrocutaneous or fasciocutaneous flaps or skin grafts. There was one local recurrence (0.5 mm original thickness); there were two patients with regional recurrences, both of whom died within a year with disseminated disease. Forty-three percent have been followed for 5 or more years and all are alive and free of disease. This suggests that malignant melanoma of the ear may be safely treated by conservative excision and reconstruction.

Adult↗
PubMed2000

Surgical management of the primary melanoma.

Conservative margins of resection have proven safe for malignant melanomas arising in a wide variety of anatomic sites. Reconstruction, however, can be a challenge in cosmetically sensitive areas. This article summarizes the authors' management philosophy, including reconstruction.

Biopsy↗
PubMed1998

Modified Le Fort III osteotomy in adult Crouzon disease.

The authors present a unique case of a woman with Crouzon disease who was treated for symptomatic exorbitism with a modified Le Fort III osteotomy. Midface advancement with reduction of exorbitism was accomplished without intermaxillary fixation. The technical details are described.

Adult↗
PubMed1997

Isolation of human ear specific cDNAs and construction of cDNA libraries from surgically removed small amounts of inner ear tissues.

We have used representational difference analysis (RDA) for subtractive hybridization of oligo dT primed directionally cloned cDNA libraries from human inner ear tissue and a B-lymphoblast cell line. Two rounds of subtraction-amplification, followed by differential hybridization of selected clones led to the isolation of genes which were specific to the ear. Sequence analysis of randomly chosen clones revealed the presence of a histidine rich Ca2+ binding protein, human dynamin, collagen type 1A1, collagen type 2A1, SPARC, human growth hormone, and several specific genes which had no sequence homology in the data base. Furthermore, to apply these techniques for isolating genes specific to distinct inner ear structures and/or cell types of inner ear for which the starting tissue material is limiting, we have used a modified PCR based protocol to construct representative cDNA libraries. We have characterized a cDNA library constructed from small amounts of inner ear tissues recovered by ablative surgical procedure involving labyrinthectomy. The potential application of these protocols for isolating genes involved in hearing and deafness is discussed.

Adult↗
PubMed1996

Expression of 32-kDa laminin-binding protein mRNA in colon cancer tissues.

Colorectal cancer initiation and progression are associated with stepwise genetic alterations. We and others have shown that a gene encoding for a 32-kDa putative laminin-binding protein (LBP-32) is overexpressed during colorectal cancer progression by Northern blots analysis. Northern blots cannot indicate the heterogeneity of expression from cell to cell and the distribution pattern of gene expression within a given tumor. In order to overcome these problems, we examined the LBP-32 mRNA expression in colorectal carcinomas by in situ hybridization. LBP-32 mRNA expression in 30 cases of primary and metastatic colorectal cancers and their respective adjacent normal tissues were detected by in situ hybridization using 35S-UTP radiolabeled antisense riboprobes. The results showed that LBP-32 mRNA was expressed at a low level in the normal colonic mucosa adjacent to the tumor compared with colon cancer tissues. Its expression in poorly differentiated colorectal cancer was much higher than that in well- and moderately differentiated colorectal cancer. More importantly, the LBP-32 mRNA was expressed more highly in the invasive lesions of the cancer and liver metastases compared with the cancer lesions in situ. Our results imply that in situ hybridization is a powerful tool in evaluating the changes in gene expression in the cancer cells and LBP-32 mRNA expression is related to progression, invasion, and metastasis of colorectal cancer.

Carcinoma↗
PubMed1995

The fate of the skin graft in laryngoplasty.

In laryngoplasty procedures, laryngotracheal soft tissue defects are often repaired using skin grafts. While stenting is necessary to approximate and immobilize the graft, prolonged stenting causes increased bacterial counts, granulation tissue formation, tissue ischemia, and graft failure. Optimal time for stent removal has not been experimentally defined. Using the ferret animal model, 24 laryngoplasty procedures were performed. The subjects were stented by group for 0, 3, 7, 14, or 28 days. Analysis consisted of quantitative bacteriology, dye perfusion, and quantitative histologic assessment of graft viability. Tissue culture results revealed that by 3 days after the procedure all groups had 10(5) CFU of bacteria per gram of tissue. Graft viability in successful procedures was maximal in the 7-day group and statistically significant from the 3-day to the 28-day groups. In conclusion, while stenting is necessary for graft adherence, prolonged exposure to local tissue sepsis leads to progressive graft destruction.

Animals↗
PubMed1994

Unusual inheritance of primary ciliary dyskinesia (Kartagener's syndrome).

Primary ciliary dyskinesia syndrome is characterised by chronic sinusitis, bronchiectasis, and, in 50% of cases, dextrocardia. It is generally believed to be inherited as an autosomal recessive disorder. In this report, we describe a family consisting of a mother and her five male children, the offspring of three different fathers, all of whom have this syndrome. This argues for either an X linked or autosomal dominant pattern of inheritance. Cytogenetic and FISH (fluorescent in situ hybridisation) analyses were done on the mother and one son and were found to be normal.

Adolescent↗
PubMed1992

Tissue expanders in the gut: a histological and angiographic study.

A study to assess the effects of an intraluminally placed tissue expander in the rabbit jejunum was performed. Oval expanders (8 cm3) were placed via a midline coeliotomy through an enterotomy on the antimesenteric border of the jejunum. The reservoir was tunnelled subcutaneously through the abdominal wall. Expansion was carried out through this port at 7-10-day intervals using 0.5-cm3 increments. At the end of the experiment, angiography was performed and routine haematoxylin and eosin-stained sections were produced. Angiography revealed an increase in vessel diameter and vascular density of the specimen. Histology showed an increase in villi size, an increase in the number of goblet cells and a marked increase in the thickness of the muscular layer. The possible applications of this technique are discussed.

Animals↗
PubMed1978

Double channel pylorus.

Radiographic and clinical features in five patients with the double channel pylorus deformity are reviewed and compared with previously reported cases. The double channel pylorus is a form of gastroduodenal fistula with a characteristic radiographic appearance. An accessory channel connects the lesser curvature of the prepyloric antrum with the duodenal bulb. A peptic ulcer lies in or immediately adjacent to the accessory channel in almost all cases. The double channel pylorus appears to be an acquired form of peptic deformity in the great majority of cases and is probably more common than the number of reported cases would imply.

Aged↗