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Biomedical subjects

S Jayachandran

Publications and source records attributed to S Jayachandran.

At least 19 recordsLinked to original sources
PubMed2006

Synthesis, characterization and in vitro biological activity studies of Cu-M (M = Cu2+, Co2+, Ni2+, Mn2+, Zn2+) bimetallic complexes.

Six new bimetallic complexes of the type CuCu, CuCo, CuNi, CuZn and CuMn were prepared. The structures of these complexes and the ligand have been proposed on the basis of FAB mass, elemental analysis, UV-vis, IR, EPR and CV studies. All the complexes completely cleave pBS (SK-) DNA at a concentration of 10 microM; however, even at lower concentrations of 2 microM and 0.1 microM, the complexes (I and Ia) showed partial cleavage. The results of the fluorescence binding studies of the metal complexes with CT-DNA showed that the presence of aliphatic ligands added additional binding effects including electrostatic, hydrogen binding and vander Waals interactions. Complexes (I, Ia) showed 50% inhibition of COX-1 and COX-2 activities at as low a concentration as 12.5 microM, 13.5 microM, 14 microM and 14.5 microM. Inhibition assay of top I and top II by different complexes in mutant yeast strains (JN394, JN394 t(-1) and JN394 t(2-5)) with all the complexes showed significant inhibition of topoisomerase at 5 microM concentration. Complexes I and Ia exhibited good anti-microbial activities against all human pathogens tested except Klebsiella pneumoniae. The following studies showed that among the synthesized bimetallic complexes, complexes I and Ia seem to be promising candidates possessing DNA cleavage activities besides anti-microbial and anti-inflammatory properties to serve as chemical nucleases and chemotherapeutic agents.

Anti-Bacterial Agents↗
PubMed2002

Detection and quantification of phytotoxic metabolites of Sarocladium oryzae in sheath rot-infected grains of rice.

AIMS: The present study describes the detection and quantification of the Sarocladium oryzae metabolites, helvolic acid and cerulenin in extracts of rice grains collected from plants infected with sheath rot. It also describes the phytotoxicity of these metabolites on rice seedlings. METHODS AND RESULTS: Helvolic acid and cerulenin in sheath rot-infected rice grains were detected using thin layer chromatography (TLC) and nuclear magnetic resonance (NMR) analyses. On the TLC plates helvolic acid and cerulenin moved as brownish yellow spots and showed R(F) values of 0.61 and 0.49, respectively. A standard assay curve was developed on the basis of selective toxicity of helvolic acid towards Calvibacter michiganensis ATCC 2140 and cerulenin towards Candida albicans 1150. The amounts of helvolic acid and cerulenin on the basis of standard assay curve were 2.2 and 1.75 microg g(-1) of infected seeds. Treatment of IR 36 rice seedlings with metabolites induced chlorosis and reduced shoot length by 20%, root length by 30% and root number by 7% relative to control. CONCLUSIONS: Helvolic acid and cerulenin were detected in infected rice grains and these metabolites induced chlorosis and reduced the seed viability and seedling health of rice. SIGNIFICANCE AND IMPACT OF THE STUDY: Antimicrobial and phytotoxic metabolites, helvolic acid and cerulenin are present in infected grains and reduce the seed viability and seedling health. These metabolites may increase the pathogenic potential and survival of S. oryzae in rice seed by competing with other seed-borne fungi.

Cerulenin↗
PubMed2002

Reconstruction of finger tip amputations with advancement flap and free nail bed graft.

Fifteen finger tip amputations through the proximal half of the nail bed were reconstructed with palmar V-Y advancement flaps and full thickness nail bed grafts. The undersurface of the V-Y flap was sutured to the nail bed remnant and the raw area was covered with full thickness nail bed grafts from the amputated part. They were followed for a minimum period of one year and the nail bed grafts took fully in all patients. The results were best in the thumb and least favourable in the little finger but all the patients were happy with the cosmetic result and the functional outcome. This technique results in an average gain of 5 mm of extra length to the nail. This is a useful technique when replantation of a distal fingertip amputation is not possible.

Amputation, Traumatic↗
PubMed1993

Cloning, over-expression and evaluation of a recombinant fusion protein of Wuchereria bancrofti towards its application as a diagnostic agent for bancroftian filariasis.

A low molecular weight (15 kDa) surface antigen of the cattle filarial nematode, Setaria digitata, was earlier shown to be specifically recognized by the antibodies from human bancroftian filarial (Mf positive) patients' sera (Theodore & Kaliraj, 1990). The filarial specific antibodies bound to a 15 kDa peptide in preparative Western blots were eluted and employed in screening of candidate antigens expressed in the genomic library of Wuchereria bancrofti at the IgG4 subclass antibody level. A recombinant clone (lambda WbG7) reacting strongly with filarial sera but poorly with sera from patients infected with non-filarial helminths was selected for further studies. The 2 kb DNA insert of the clone lambda WbG7 was recloned into a pMAL vector and the recombinant clone pGT7 thus obtained was over-expressed and affinity purified. The purified 105 kDa fusion protein of the clone pGT7 was specific and was not recognized by the non-filarial sera at the IgG4 level. All microfilaraemic individuals were positive by IgG4 assay. However, similar attempts to diagnose by filarial-specific IgE assays failed to recognize microfilaraemic individuals. Moreover, by filarial-specific IgG4 assays, the endemic normals were distinctly divided into two groups, showing higher and lower recognition for this antigen indicating current and past/no infection. Among the filarial-IgG4 (assay)-positive 'endemic normals', 14% showed 'microfilariae' during repeated peripheral night blood examination, confirming the validity of the recombinant antigen, pGT7 based assay.

Animals↗
PubMed1987

Paraneoplastic syndrome in squamous cell carcinoma of urinary bladder.

Hypercalcemia with metastatic tumor is a common clinical entity, but without metastasis, hypercalcemia as a manifestation of squamous cell carcinoma of the bladder is rare. We present a case demonstrating immunoreactive parathyroid hormone-like activity in a nonmetastasizing tumor. Hypercalcemia subsided after ablative surgery.

Aged↗
PubMed1985

Effects of chlorpromazine on ischemic rat kidney: a functional and ultrastructural study.

The effects of chlorpromazine, an agent with inhibitory effects of calcium influx, phospholipase activation, and Na-K-ATPase, on preserving renal function and proximal tubular ultrastructure were evaluated in renal ischemia. After right nephrectomy chlorpromazine (0.025 mg) or 1 ml of 0.9 per cent saline was selectively administered to the rat kidney immediately prior to a sixty-minute occlusion of the remaining renal artery. Pretreatment with chlorpromazine resulted in a significant attenuation in the rise in postischemic serum creatinine. Hypothermia of the kidney during ischemia provided an additional protective effect. Electron microscopic study of the proximal convoluted tubule demonstrated that the structural damage was less severe in chlorpromazine-treated rats and virtually complete preservation of a normal ultrastructure was observed when hypothermia was added.

Animals↗
PubMed1985

Complications from external (condom) urinary drainage devices.

External urinary drainage devices are usually considered safe and are in wide clinical use. There are only a few reports of complications arising from their improper use. We present 6 patients who suffered major complications from external condom drainage at home. The etiology and preventive measures are discussed.

Adolescent↗
PubMed1985

Urinoma--a rare presentation of carcinoma of the bladder.

Urinoma as a presenting sign of carcinoma of the bladder, as occurred in this case, is rare. Aspiration of the cystic mass under sonography and chemistry of the fluid confirmed the diagnosis. The inferior extension of the urinoma on CT scan confirmed the gradual fading of Gerota's fascia into the retroperitoneum. Abdominal mass in the form of a urinoma is an uncommon presentation and only a few documented cases are reported in the literature. This case illustrates that the Gerota's fascia fades inferiorly into the retroperitoneum.

Biopsy↗
PubMed1984

Metastases to the penis from renal cell carcinoma.

Extensive venous communication among the pelvic, lumbar, penile and left renal veins may cause metastasis to the genitalia from left renal adenocarcinoma. To prevent this, we propose that during radical nephrectomy the spermatic and, lumbar veins be ligated immediately following the ligation of the renal artery and vein.

Carcinoma, Renal Cell↗
PubMed1984

The value of urinary fibrin/fibrinogen degradation products as tumor markers in urothelial carcinoma.

Urinary fibrin/fibrinogen degradation products as biological tumor markers in urothelial carcinoma have been studied and compared to urinary cytology. In 93 per cent of the patients with urothelial carcinoma urinary fibrin/fibrinogen degradation product levels were elevated significantly. There was excellent correlation when the urinary cytology and urinary fibrin/fibrinogen degradation product results were compared together to cystoscopic findings.

Carcinoma, Transitional Cell↗
PubMed1984

Fascial pathways of extravasation of blood in lower abdomen following angiography-anatomic and clinical correlation.

The extravasation of urine following traumatic rupture of the urethra or periurethral abscess is well known to clinicians. The extravasation of blood following angiography, in the same anatomical space, is rare. Extravasation of fluids in the lower abdomen, groin and external genitalia follows distinct anatomical pathways. This case illustrates the anatomical pathways and emphasizes their clinical importance.

Angiography↗
PubMed1983

Yeast killer dsRNA plasmids are transcribed in vivo to produce full and partial-length plus-stranded RNAs.

In vivo transcripts of the L (4.5 kb) and M (1.9 kb) dsRNA plasmids were examined in type I killers of Saccharomyces cerevisiae. Transcripts for both plasmids include full-length (l,m) and partial-length (la,ma) single-stranded species. Both L-dsRNA transcripts (l,la) have in vitro mRNA activity for L-P1, previously shown to be identical to ScV-P1, the 88,000 dalton major capsid protein of the virus-like particles containing L- and M1-dsRNAs. 1, but not 1a, is bound to poly(U)-sepharose and may be polyadenylated. Other L-dsRNA gene products and their transcripts may exist. For M1-dsRNA, both species (m, ma) have in vitro mRNA activity for M1-P1, the 32,000 dalton pre-protoxin encoded by M1-dsRNA. Both m and ma are bound to poly(U)-Sepharose and ma is probably a 5' terminal fragment of m. A functional model for M1-dsRNA killer plasmid structure is presented.

Animals↗