Search PubMed⌕ Search

Biomedical subjects

R Sehgal

Publications and source records attributed to R Sehgal.

84 records · Page 5Linked to original sources
PubMedDate not supplied

Structural evaluation of porcine heart valve prostheses with radiofrequency ultrasound.

BACKGROUND: Bioprosthetic heart valve use is limited by progressive degeneration. Early degenerative changes are often occult, making assessment of tissue integrity difficult. Ultrasound tissue characterization may detect alterations in tissue structure and allow early detection of leaflet degeneration. METHODS: Using a modified echocardiographic unit (Acuson), radiofrequency (RF) integrated backscatter amplitude (IBA) (integral/RF/dt) was measured in 38 leaflets from nine explanted and six control porcine valves. Regions of interest in each leaflet were studied using four ultrasound frequencies. Radiographic gray scale mean and leaflet thickness were measured at each region of interest. Percent collagen and mineral were calculated for each region of interest using color-image processing of histologic sections and compared to IBA. RESULTS: IBA values for control vs. explanted leaflets were (mean value+/-standard deviation): 8.2+/-4.69 dB vs. -4.7+/-4.64 dB at 7.0 MHz; -5.8+/-4.34 dB vs. -3.1+/-5.34 dB at 5.0 MHz; -3.8+/-3.38 dB vs. -2.1+/-3.18 dB at 3.5 MHz; and -9.0+/-4.58 dB vs. -7.1+/-4.25 dB at 2.5 MHz. Collagen content was 27.7+/-8.50% vs. 33.2+/-10.90%, mineral content was 0.1+/-0.10% vs. 2.1+/-4.30%, and radiographic gray scale mean was 150.6+/-1.96 vs. 145.3+/-5.14 for control vs. explanted leaflets, respectively. For control and explanted leaflets IBA, collagen content, mineral content, and radiographic gray scale mean were different (control vs. explanted P<0.05). Leaflet thickness was also noted to be different between the two groups. IBA was different among explanted leaflets with low, medium, and high mineral content. CONCLUSION: IBA was found to be a useful technique to differentiate normal from explanted porcine prosthetic valves in vitro. This method may be useful in the serial assessment of bioprosthetic leaflet degenerative properties in vivo.

Adult↗
PubMedDate not supplied

Cytokine mRNA expressions in symptomatic vs. asymptomatic amoebiasis patients.

Infection with Entamoeba histolytica results in high mortality worldwide. Studies on the cytokine response in symptomatic and asymptomatic amoebiasis (caused by E. histolytica, the pathogenic species and E. dispar, the non-pathogenic species) subjects and their correlation with symptomatology are lacking. The present study reports the cytokine response (TNF-alpha, IFN-gamma, IL-4, IL-10 and TGF-beta) in such subjects as measured by RT-PCR. The results showed significantly (< 0.05) higher expressions of IL-10 and TGF-beta in the symptomatic group as compared to the asymptomatic and healthy controls. The cytokine profile indicated the role of suppressive immune response in symptomatic amoebiasis patients.

Adolescent↗
PubMedDate not supplied

Routine vaginal cuff smear testing in post-hysterectomy patients with benign uterine conditions: when is it indicated?

BACKGROUND: By the age of 60 years, an estimated 33% of women will have undergone a hysterectomy. Approximately 85% of these hysterectomies are performed for benign disease. The object of this study was to evaluate cytologic findings from vaginal cuff smears in patients who have undergone hysterectomy for benign uterine conditions. METHODS: We conducted a community-based retrospective study and follow-up of women with vaginal cuff cytologic smears who had had a hysterectomy for benign uterine conditions. A total of 220 women were randomly selected who had one or more vaginal cuff smears. The main outcomes measures were invasive carcinoma, dysplastic lesions, and infections detected by vaginal cuff smear testing. The setting was a large inner-city hospital. RESULTS: Ninety-seven percent of 220 women who underwent hysterectomy for benign uterine conditions and who were observed for an average of 89 months had no cytologic abnormalities on vaginal cuff smears. Cytologic evaluation found no invasive carcinomas. Dysplastic lesions were detected in 7 patients (3%). Seventy percent of patients (n = 154) had one or more infections; these infections included bacterial vaginosis (106), trichomoniasis (95), candidiasis (40), koilocytosis suggestive of human papilloma virus (HPV) infection (3), and cytopathic effect of herpes (4). The prevalence of koilocytosis was much higher in the patients with dysplasia (P = .0003). CONCLUSIONS: Most routine vaginal cuff cytology screening tests need not be performed in women who have had a hysterectomy for benign uterine conditions.

Adult↗
PubMedDate not supplied

Cryptosporidiosis in a tertiary care hospital.

BACKGROUND: Cryptosporidium, an important cause of diarrhoea, has been reported worldwide both in immunocompetent and immunocompromised individuals and has emerged as a serious public health problem. This study was undertaken to assess the present status of cryptosporidiosis in children and adults with diarrhoea who attended the Nehru Hospital, Chandigarh which is a tertiary care hospital. METHODS: Routine stool examination was done using saline and iodine stained preparations for various parasites. Modified Ziehl-Neelsen and rapid safranin-methylene blue techniques were used to detect Cryptosporidium in 2000 stool samples (1645 adults, 355 children) from March to November 1998. RESULTS: Of the 2000 samples, 205 (10.2%) were positive for various parasites. Five (1.4%) children were positive for Cryptosporidium and one child was positive for human immunodeficiency virus. In adults, Cryptosporidium was found in only one patient (0.06%). Giardia lamblia was the commonest parasite detected both in adults (4%) and children (15.2%). CONCLUSION: The present study highlights the importance of Cryptosporidium as a cause of diarrhoea, especially in children. Thus, there is a need for specific staining techniques to detect Cryptosporidium in routine diagnostic laboratories.

Adult↗
PubMedDate not supplied

Cryptosporidiosis and related diseases.

Cryptosporidium, is a parasite classified as a member of the class Sporozoea and Subclass Coccidia. The other parasites which are grouped under the Coccidia Subclass are Isospora, Sarcocystis, Plasmodium, Piroplasmia and Microspora. Cryptosporidium, Isospora, Sarocystis and recently some of the Microspora have been observed to cause infections of the gastrointestinal tract. This review summarizes the recent developments in our knowledge about these parasites especially those which are of medical importance.

Cryptosporidiosis↗
PubMedDate not supplied

Western blotting.

Explore the source record for details and available documents.

Blotting, Western↗