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Biomedical subjects

A Srivastava

Publications and source records attributed to A Srivastava.

At least 73 records · Page 4Linked to original sources

Efficacy of extracorporeal shock wave lithotripsy for solitary lower calyceal stone: a statistical model.

OBJECTIVE: To evaluate the effect of inferior calyceal radiographic anatomy, number of extracorporeal shock wave lithotripsy (ESWL) sessions and stone size on the successful clearance of solitary inferior calyceal calculi after ESWL. PATIENTS AND METHODS: In a prospective study between January 2001 and November 2002, 66 renal units with a solitary inferior calyceal calculus of < or = 2 cm were treated with electrohydraulic ESWL. The infundibulopelvic angle (two definitions), infundibulovertebral angle, inferior calyceal infundibular diameter, infundibular length, cortical thickness over the lower pole, number of minor calyces and stone size were determined from intravenous urography before treatment. The number of ESWL sessions was also included in the analysis. Treatments which produced residual fragments not clearing within 3 months of satisfactory fragmentation were considered as failures. All patients in whom the treatment failed were treated successfully by percutaneous nephrolithotomy. The data were then analysed using two different statistical methods; first by intravariable differences using the test of proportion (Fisher's test) and then all the variables together using logistic regression. RESULTS: At 3 months 78.8% of the renal units were clear of stone. All intravariable differences were statistically significant except stone size (<1 cm, 1-2 cm). In a multivariate analysis of all variables, only stone size was the most important predictor for successful stone clearance (P = 0.03). CONCLUSIONS: ESWL is the initial treatment of choice in selected patients with inferior calyceal stones. The stone size appears to be the most important predictor for stone clearance.

Adolescent↗

Laparoscopic live-donor nephrectomy: modifications for developing nations.

OBJECTIVE: To describe modifications to laparoscopic live-donor nephrectomy (LLDN) to make it more cost-effective for developing countries; LLDN was developed as a better alternative to conventional donor nephrectomy, with advantages of an earlier return to normal activities and smaller scars, but is not popular in developing countries because of high cost of disposable items. PATIENTS AND METHODS: From January 2000 to January 2002, 148 LLDNs were performed, of which two used a hand-assisted technique, 17 the standard technique, 79 a modified laparoscopically assisted cost-saving approach and 50 by the modified technique. In the latter approach the kidney was delivered through a 6-8 cm anterior subcostal flank incision. In last 50 patients we further modified the technique, clipping the hilum using endoclips and delivering the kidney by holding the lateral pararenal fat through a 5 cm iliac fossa incision. RESULTS: The mean age, operative duration, warm ischaemia time, blood loss, analgesic requirements, pain score and hospital stay were comparable among the various techniques used. Re-exploration was required in four patients (bleeding in two, trocar-induced bowel injury in two). Immediate complications after surgery occurred in 20% of patients. Using endoclips, the cost was considerably reduced, from $400 to $290. The iliac fossa incision was aesthetically pleasing and more acceptable to patients. CONCLUSION: These modifications are relevant in the context of a developing nation, as they provide all the benefits of LLDN at reduced cost and with better cosmetic results.

Adult↗

Alterations in expression of retinoid receptor beta and p53 in oral submucous fibrosis.

OBJECTIVE: Knowledge of the molecular pathogenesis of oral submucous fibrosis (OSF), a potentially malignant condition with high risk of transition to oral cancer, is meagre. Alterations in the expression of retinoic acid receptor beta (RARbeta) and tumor suppressor gene, p53 are early events in oral tumorigenesis. The aim of this study was to investigate the alterations in the expression of RARbeta and p53 in OSF lesions and determine their association with disease pathogenesis. METHODS: The expression of RARbeta and p53 proteins was analyzed by immunohistochemistry in 50 cases of OSF and 30 histologically normal oral tissues. RESULTS: No detectable RARbeta expression was observed in 35 of 50 (70%) OSF cases. p53 protein accumulation was observed in 24 of 50 (48%) OSF cases analyzed. Thirty-six percent OSF lesions showed loss of RARbeta and p53 overexpression. Interestingly, 41 of 50 (82%) of OSF lesions showed altered expression of at least one of these two proteins. CONCLUSION: Altered expression of either RARbeta or p53 in majority of OSF lesions suggests their association with disease pathogenesis and warrants follow-up to determine whether OSF lesions harboring concomitant alterations in RARbeta and p53 are at a high risk of transition to malignancy.

Adolescent↗

Fine-needle aspiration cytology of the testis: can it be a single diagnostic modality in azoospermia?

PURPOSE: The aim of this study was to determine whether fine-needle aspiration cytology (FNAC) of testis alone is sufficient to diagnose testicular function and whether follicle-stimulating hormone (FSH) estimation can be safely eliminated from the evaluation protocol of the azoospermic subject. MATERIALS AND METHODS: We studied 46 adult azoospermic males who were infertile for more than 2 years following marriage. Hormonal profile was done in all. Later all 46 patients were subjected to bilateral FNAC of the testes. The cytological findings were correlated with histological findings. RESULTS: We found 95.65% agreement between FNAC and testicular biopsy. Though serum FSH estimation was done in all patients in this series, in none of the cases did it affect overall management. CONCLUSION: FNAC is a quick, safe and minimally invasive modality. Following a well-performed semen analysis in an azoospermic subject, it appears that FNAC may be the only investigation needed. It provides a reliable diagnosis in patients with either obstructive or non-obstructive azoospermia. Routine estimation of FSH can be omitted from the investigative protocol in these patients.

Adult↗

Molecular characterization of a strain of cucumber mosaic virus based on coat protein and movement protein genes.

Cucumber mosaic virus (CMV) A strain (CMV-A) isolated from Amaranthus tricolor was partially characterized at molecular level. Complete coat protein (CP) and movement protein (MP) ORFs were cloned and sequenced. The 657 bp region of CP gene and the 840 bp region of MP gene encode 218 and 276 amino acids, respectively. CP, at nucleotide level, showed 90-98% sequence identity with the CMV subgroup I and less than 80% with the CMV subgroup II, it showed at amino acid level 92-96% identity with the subgroup I and 74-87% with the subgroup II. The nucleotide and amino acid sequence identities of MP ranged in 91-94% and 92-96%, respectively with the subgroup I but in 81-83% with the subgroup II. Phylogenetic trees generated from nucleotide and amino acid sequences of both CP and MP genes identified the virus strain as a member of the subgroup IB. CMV-A CP also displayed a remarkably higher homology with Indian strains of CMV than with other CMV strains and formed a separate cluster within the subgroup IB.

Amino Acid Sequence↗

Implantation in vitro: co-culture of rat blastocyst and epithelial cell vesicles.

Implantation of blastocysts involves conversion of maternal and embryonic cell surfaces from a nonadhesive to an adhesive state in response to the internally driven developmental program or to externally generated factors. However, the intricacies of the cellular and subcellular changes that promote the attachment are not known, because these changes are difficult to determine in situ because of the nonaccessibility of the site. To overcome this, an in vitro model of implantation was developed by co-culturing rat blastocysts and uterine epithelial cells of the same gestational age (day 5 postcoitum; plug day as day 1) in drops hanging from the lid of a Petri dish. The system was used to study the changes on the surface membranes of the cells of the trophectoderm and uterine epithelium and to evaluate the antiadhesive activity of the newly designed test substances. The isolated epithelial cell vesicles were co-cultured with zona-free blastocysts in the microdrops (40-50 microl) hanging from the lid of a 60-mm Petri dish. The lid was placed over the lower dish, which was presaturated with the medium. The culture was examined 48 h later to determine the site of adhesion of epithelial cell vesicles with the trophoblasts lining the blastocyst. The cell-cell adhesion was monitored on a computerized image analyzer. To validate the adhesion of blastocysts and epithelial cell vesicles in co-culture, the expression of a cell adhesion molecule, uvomorulin, was studied using immunocytochemical technique after incubating with antiuvomorulin antibody. Intense staining was noted on the membrane surfaces at the site of attachment of the blastocyst and cell vesicles.

Animals↗

Synthesis and antimycobacterial activity of 3,5-disubstituted thiadiazine thiones.

A series of 3,5-disubstituted thiadiazine thiones (4-24) have been synthesized by reaction of primary amines with carbon disulphide followed by cyclocondensation of the resulting intermediate with formaldehyde and primary amines or amino acids. The compounds were screened for antitubercular activity in vitro against Mycobacterium tuberculosis H37Rv. Three compounds 4, 12 and 18 showed antimycobacterial activity with MIC 12.5 microg/mL. Compound 4, was tested in vitro against five multidrug resistant (MDR) strains of M. tuberculosis and was found to be active. Compound 4 also exhibited activity in vivo. While all the mice died in the untreated group, the mean survival time (MST) of the compound treated mice was enhanced, 33% mice were surviving in treated group and the load of bacilli in the lung was considerably less in the compound treated group than in the untreated control group.

Animals↗

A non-ionic water-soluble seed gum from Ipomoea campanulata.

A non-ionic water-soluble galactomannan, having galactose and mannose in 2:3 molar ratio was isolated from endosperm of the seeds of Ipomoea campanulata. The seed gum was found to have linear chain of beta (1-->4) linked mannopyranosyl units with D-galactose side chains attached through alpha (1-->6) linkage to the main chain. This structure is similar to many commercial gums like Guar, Carob and Locust bean gum. Various physical properties of the gum were studied in order to explore the possibility of commercial exploitation of the seed gum.

Galactose↗

Mini incision live donor nephrectomy: an optimal approach for the developing countries.

OBJECTIVE: Laparoscopic donor nephrectomy (LD) is rapidly gaining popularity, however, this may not be affordable by donors in many developing countries because of its high cost. We describe our mini flank incision (MD) donor nephrectomy technique and its outcome. METHODS: A 7-10-cm subcostal rib sparing transverse incision was given 2 cm lateral to the tip of the 12th rib, towards the lateral border of rectus muscle. All dissections were performed with help of long retractors and instruments, vessels were transfixed and cut. In last 45 cases, vessels were clipped with Liga or Weck clips. Donors and recipients outcome was analysed. RESULT: From January 2000 to December 2002 a total of 148 patients underwent donor nephrectomy by mini incision technique. Mean patient age was 44.8 +/- 7.3 yr (range 20-70 yr). Nephrectomies were performed in 115 patients on the left side and in 33 cases on the right side. The mean incision length was 9.1 +/- 1.8 cm (range 7-10 cm). Mean operative time was 105 +/- 10.5 min (70-130 min). Mean analgesic (Tramadol) requirement was 205 +/- 52 mg; postoperative hospital stay was 2.2 +/- 0.5 d. Twelve per cent patients developed fever and 4% had superficial wound infection in postoperative period. Three patients required blood transfusion. Mean convalescence period was 22 +/- 2.8 d. CONCLUSION: Extrapleural, extraperitoneal, subcostal mini incisions live donor nephrectomy is a relatively safe procedure with low morbidity. This technique has a shorter hospital stay, early convalescence and better cosmesis. It is cost-effective and is an ideal substitute for the developing country.

Adult↗

Determination of the breakpoint and molecular diagnosis of a common alpha-thalassaemia-1 deletion in the Indian population.

The previously described South African type alpha-thalassaemia-1 mutation was identified in Indian HbH patients using a polymerase chain reaction (PCR) strategy. A multiplex PCR assay was devised to detect heterozygotes and homozygotes. This alpha-thalassaemia-1 mutation was found to be the commonest determinant causing HbH disease in this population. In one family this mutation was found in combination with a novel splice donor mutation alpha2 IVS I-1 (G-->A). Characterization of the breakpoint junction sequence revealed, in addition to a 23 kb deletion, that there was an addition of approximately 160 bp bridging the breakpoints. Similar to other deletions in the alpha-globin gene cluster, there is an Alu repeat-mediated mechanism for the origin of the deletion.

Adult↗

Factor replacement therapy in haemophilia--are there models for developing countries?

Successful models for factor replacement in severe haemophilia involves prophylactic or on-demand administration of large quantities (1500-9000 IU kg-1 year-1) of very high purity factor concentrates starting early in life. The prohibitive cost of these protocols make them completely impractical in developing countries where the quantity of factor used for replacement therapy is much lower and varies considerably (25-500 IU kg-1 year-1). At this level of treatment, as some joint damage is inevitable, the aim of therapy shifts to preventing disability and preserving reasonable joint function rather than perfect architecture. There are no carefully recorded data on long-term outcome of musculo-skeletal function on these doses. Appropriate studies are needed to document such data. With regard to products for factor replacement, economic compulsions lead to the use a variety of factor concentrates and blood-bank products for replacement therapy. Most patients in the developing world do not have access to adequate replacement therapy. Among the rest, some get limited quantities of plasma-derived concentrates while others use cryoprecipitate, fresh frozen plasma or even whole blood. Since the superiority of virus-inactivated purified factor concentrates in achieving the aims of replacement therapy is well established, the aim should be to provide this for all people with haemophilia. This can be achieved by production of such concentrates locally or by importing them. Different models are possible depending on the circumstances in each country.

Clinical Protocols↗

Substitution urethroplasty for anterior urethral strictures: a critical appraisal of various techniques.

OBJECTIVE: To retrospectively compare the outcome of various techniques of substitution urethroplasty. PATIENTS AND METHODS: Between 1989 and 2000, 109 patients (mean age 39.5 years) underwent substitution urethroplasty for recurrent anterior urethral strictures. Between 1989 and 1995 the procedure was by ventral placement of free grafts (bladder mucosa, buccal mucosa, penile skin) or penile skin flaps. From 1995 onwards the flaps and grafts (buccal mucosa) were applied either ventrally or dorsally. Stricture recurrence and the complications associated with each technique were compared. RESULTS: Ventral onlay repairs were associated with a higher incidence of complications than dorsal repairs, e.g. postvoid dribbling (39% vs 23%, P = 0.01), ejaculatory dysfunction (20% vs 5%, P = 0.03) and flap/graft pseudo-diverticulum or out-pouching (26% vs 2.6%, P = 0.01). Superficial penile skin necrosis was significantly more common with the use of penile skin flaps than with free grafts. There was no significant difference in stricture recurrence, erectile dysfunction and residual penile deformity among the various techniques. CONCLUSIONS: Dorsal free graft/flap onlay urethroplasty gives better results than ventrally placed free grafts/flaps. Dorsal onlay buccal mucosal urethroplasty is a versatile procedure and associated with fewer complications than other substitution methods.

Adolescent↗

Spiracular indices in Anopheles stephensi: a taxonomic tool to identify ecological variants.

Thoracic spiracle length and its index was examined for their ability to discriminate two ecological variants, type form and mysorensis, of Anopheles stephensi in the adult stage. The type form is exclusively domestic in all seasons, whereas the mysorensis variant occupies the outdoor niche during monsoon and postmonsoon seasons, with spillover into domestic sites during summer ecological stress periods. A statistically significant co-relation was established between the ridge count of the egg and two adult measurements, the thoracic spiracle length, and the spiracular index. In An. stephensi type form, average spiracle length was 0.11-0.12 mm and average spiracular index was 8.09-9.23, whereas in mysorensis, the corresponding figures were 0.09-0.10 mm and 6.82-7.60. These parameters showed consistent variations in population of mosquitoes that emerged during monsoon and summer season. The thoracic lengths in both variants remained constant, and only spiracular lengths showed fluctuations in three seasonal populations. These measures provide discrimination of adult variants--identifications that are essential in malaria control programs.

Animals↗