PubMed Health⌕ Search

Biomedical subjects

R V Singh

Publications and source records attributed to R V Singh.

At least 19 recordsLinked to original sources
PubMed2006

Temporal expression of transforming growth factor-beta2 and myostatin mRNA during embryonic myogenesis in Indian broilers.

TGF-beta2 and myostatin, the members of TGF family, act through both autocrine and paracrine mechanisms to regulate the growth and differentiation at various developmental stages in chicken. The kinetics and expression profile of these two growth factors were investigated by semi-quantitative RT-PCR, during the myogenesis of Indian broiler chickens. Total RNA was isolated from whole embryos on each of embryonic days (E) 0-6 (n=3 per day) and from the biceps femoris muscle at E7-E18 (n=3 per day). The expression of TGF-beta2 was noticed on E2 that remained at the same level until E6. In biceps femoris muscle, higher level of TGF-beta2 expression was observed during E7-E12, which decreased gradually thereafter. These findings suggested that TGF-beta2 might be a regulatory factor participating in the myogenesis of chicken embryos. Initial myostatin expression was noticed on E1, even before the myogenic lineage is established in embryo. This finding suggested an additional role of myostatin in early chicken embryo development, other than myogenesis. Furthermore, myostatin expression was significantly higher on E3 as compared to earlier studies, where initial higher level was observed at E2, suggesting the differential expression of myostatin among breeds. Higher and almost static myostatin expression was noticed in biceps femoris muscle during the entire period of myogenesis (E7-E18). In the present study, the ontogeny of myostatin expression coincided with myogenesis of chicken. Therefore, it may be hypothesized that myostatin is not only a major determinant of muscle mass, but also involved in early embryogenesis in chickens.

Animals↗
PubMed2006

Investigations of the possible pharmacological effects of organotin(II) complexes.

Antitumour, antifertility and histopathological investigations were carried out on male rats by the use of organotin complexes. The organotin complexes were synthesized by the alkylation of [Sn(TAML(n))Cl(2)] (n=1-4 and TAML(n) represents the tetraazamacrocyclic ligands) in the presence of CH(3)I or C(2)H(5)Br. The structures of all the complexes have been established on the basis of elemental analyses, conductivity measurements, IR, (1)H NMR, (13)C NMR, (119)Sn NMR and X-ray spectral data. The antitumour effect of the compounds was examined on swiss mice. The results obtained clearly indicated that the compounds, [C(2)H(5)Sn(TAML(3))C(5)H(5)N] and [C(2)H(5)Sn(TAML(4))C(5)H(5)N] display effective antitumour activity. The emphasis has been given on in vivo study on male albino rats (Rattus norvegicus) by performing serum analyses, blood analyses and fertility test.

Animals↗
PubMed2006

Residues of fluoroquinolone drugs in the cloacal gland and other tissues of Japanese quail.

1. In this study we investigated the residues of fluoroquinolone drugs (ciprofloxacin and pefloxacin) in the cloacal gland (a site of foam synthesis) and other tissues such as breast muscle, testes, brain, kidney and plasma. 2. Fifty-four healthy male Japanese quail were selected at random from a flock, maintained under uniform husbandry conditions and divided into three groups, each of 18 birds. Group I (control) received 1 ml vehicle (normal saline 0.9% (w/v) NaCl) daily for 12 d through the intraperitoneal route. Birds of groups II and III received ciprofloxacin and pefloxacin by the same route at the rate of 10 and 12 mg/kg body weight, respectively, every day for a similar period. 3. Birds from each group were killed, at 1, 5 and 10 d after the cessation of treatment, to collect the cloacal gland together with other tissues that were analysed for residual drugs. 4. Cloacal gland retained the maximum drug residues of ciprofloxacin (60%) and pefloxacin (80%) on d 10 compared with that on d 1 after drug withdrawal. The drug residues were found 60 and 80% in ciprofloxacin and pefloxacin groups, respectively, in the cloacal gland tissue even on d 10 after withdrawal of the treatment. 5. In the ciprofloxacin-treated group, all tissues except cloacal gland contained very small amounts of the drug residues on d 10 after treatment ended. In the pefloxacin group the cloacal gland, breast muscle and kidney retained a fairly high amount of drug even on d 10 after treatment ceased. No residues of pefloxacin were detectable in testes and brain throughout. 6. In conclusion, the cloacal gland in Japanese quail acted as the largest sink for the fluoroquinolone drugs. Ciprofloxacin was more widely distributed in different tissues and persisted for a shorter period than pefloxacin.

Animals↗
PubMed2005

Differential expression of inducible nitric oxide synthase and cytokine mRNA in chicken lines divergent for cutaneous hypersensitivity response.

Phytohemagglutinin (PHA)-induced delayed-type hypersensitivity is an immunocompetent trait considered an indicator of cell-mediated immune or T-cell responses. Divergent selection was performed to generate high and low lines for response to PHA-P. Extreme-responder birds of the F2 generation in each line were used to study possible differences in macrophage activity and the associated functional genes. To evaluate macrophage activity, nitric oxide (NO) was estimated both systemically in serum and in in vitro monocyte culture. Semi-quantitative RT-PCR was used to detect the differential mRNA expression patterns of iNOS and MIP-1beta in monocyte culture, whereas T(H)1 cytokines (IL-2 and IFN-gamma) were studied in peripheral blood mononuclear cells (PBMC) at different time intervals after lipopolysaccharide (LPS) induction. The high line showed strong systemic, as well as in vitro NO production, compared to the low line, upon stimulation with NDV and LPS, similar to early and high iNOS mRNA expression. Following the pattern of iNOS gene expression, an early strong expression of cytokines with powerful iNOS-inducing action, such as IFN-gamma and the chemokine MIP-1beta, was observed in the high line. In contrast, for response to PHA-P, low expression of IL-2 was observed in the high compared to the low line. In conclusion, the study revealed that divergent selection for response to PHA-P resulted in a divergent effect on T(H)1 cell activity, resulting in altered macrophage function in chickens. Selection, based on response to PHA-P, could lead to more resistant birds or birds with an enhanced immune response.

Animals↗
PubMed2005

The effect of carbon as an energy source for biological denitrification through Pseudomonas stutzeri.

The biological denitrification processes possess many advantages in comparison to other denitrification processes. The present study was undertaken to observe the effect of quantity of carbon on biological denitrification with Pseudomonas stutzeri at different C/N ratios. The results obtained in the present investigations show that the pH and alkalinity of the effluent increased with increase in C/N ratio due to alkalinity generated during denitrification. The COD of the influent was increased with increase in C/N ratio. The effluent COD was nil under pseudo-steady state condition up to the C/N ratio of 2.5. Above this C/N ratio, the organics started entering in the treated water. The maximum feasible economic reduction of NO(3-)N from 51.6 mg/l to 1.2 mg/l occurred at C/N ratio of 2.5 and the obtained concentration of NO(3-)N was found to be lower than the tolerance limit (10 mg/l) prescribed by the WHO. The present work provides a feasible approach for a more efficient NO(3-)N removal process.

Biodegradation, Environmental↗
PubMed2004

Biologically relevant tetraazamacrocyclic complexes of manganese: synthetic, spectral, antimicrobial, antifertility and antiinflammatory approach.

The testicular sperm density, sperm morphology, sperm motility, density of cauda epididymis spermatozoa and fertility in mating trials and biochemical parameters of reproductive organs have been examined and discussed for [Mn(N(4)MacL(n))(NO(3))(2)] (where N(4)MacL(n) represents the tetraazamacrocyclic ligand molecule with n=1-4) type of complexes. An attempt also has been made to correlate the structural aspects of the compounds with their anti-inflammatory activity. The 14-18 membered tetraamide macrocyclic ligands N(4)L(1)-N(4)L(4) used during these investigations have been prepared by the condensation of 1,2-diaminoethane or 1,3-diaminopropane with malonic or succinic acid in the presence of condensing reagents, dicyclohexylcarbodiimide and 4-dimethylaminopyridine. On reduction, these macrocyclic ligands give a new series of tetraazamacrocyles [N(4)MacL(n)] and their complexes with manganese(II) nitrate. The ligands and their complexes were characterized by elemental analyses, molecular weight determinations, infrared, electronic, mass and X-ray structural analyses. An octahedral geometry for these complexes has been confirmed by spectral studies. On the basis of the chemical composition, the representation of the complexes as [Mn(N(4)MacL(n))(NO(3))(2)] has been established. The ligands and their complexes have been screened in vitro against a number of pathogenic fungi and bacteria to assess their growth inhibiting potential.

Animals↗
PubMed2003

Antifertility, antibacterial, antifungal and percent disease incidence aspects of macrocyclic complexes of manganese(II).

Macrocyclic complexes of Mn(II) were synthesized by template condensation using 2,6-diaminopyridine and diethylenetriamine with malonic, succinic, glutaric and adipic acids. The reaction proceeded smoothly to completion. These 16- to 24-membered N(6), but behaving as tetradentate, macrocyclic complexes were characterized by elemental analyses, molecular weight determinations, infrared, electronic, mass and X-ray spectral analyses. The elemental analyses are consistent with the formation of complexes [Mn(N(6)L(n))Cl(2)]. All the complexes are stable and monomeric in nature, as indicated by the molecular weight determinations. The spectral studies confirmed the proposed framework of the new macrocyclic complexes and indicated an octahedral geometry around the central metal atom. The complexes were screened in vitro against a number of pathogenic fungi and bacteria to assess their growth-inhibiting potential. The testicular sperm density, sperm morphology, sperm motility, density of cauda epididymis, spermatozoa and fertility in mating trials and the biochemical parameters of the reproductive organs of the rat were examined and are discussed.

Animals↗
PubMed2002

Within- and between-strain genetic variability in White Leghorn population detected through RAPD markers.

1. Five White Leghorn (WLH) strains, namely G, H, I, J and C, differing in selection history, were screened for randomly amplified polymorphic DNA (RAPD) polymorphism using 50 random decamer primers. 2. Only 12 primers detected polymorphism between the strains. Out of 96 bands scored using these primers, only 21 (21.9%) were found to be polymorphic. 3. Strains differed considerably for within-population genetic similarity, estimated either by band sharing (WS=0.836 to 0.968) or band frequency (WF=0.820 to 0.969). 4. Between-strain genetic similarity estimates, based on band sharing (BS) as well as on band frequency (BF) ranged from 0.756 to 0.958 and from 0.830 to 0.996, respectively. Strains C and H were most closely related to each other, while J appeared to be more distant from other strains. 5. The between-strain genetic distance estimates also revealed similar trends. 6. A phylogenetic tree, derived using Nei's coefficient of similarity revealed similar relationships between the WLH strains.

Animals↗
PubMed2002

Effect of naked neck gene (NA) and frizzle gene (F) on immunocompetence in chickens.

1. A total of 98 birds belonging to 4 genetic groups from two specialised populations--heterozygous naked neck (NA*NA/NA*N) and normally feathered (NA*N/NA*N) from one specialised population and heterozygous frizzle (F*F/F*N) and normally feathered (F*N/F*N) from another specialised population--were evaluated for general immunocompetence by assessing antibody response to SRBC, haemolytic complement level in the serum, in-vivo cell mediated immune (CMI) response to Concanavalin-A (Con-A) and a phagocytic index at 10-12 weeks of age. 2. The naked neck gene did not seem to influence the antibody response to SRBC, CMI to Con-A or the phagocytic index. However, significantly higher haemolytic complement level in serum was observed in birds carrying a copy of the NA mutation as compared to the normally feathered birds. 3. Similar trends were observed for the frizzle gene.

Animals↗
PubMed2001

Genetic diversity among chicken breeds estimated through randomly amplified polymorphic DNA.

The randomly amplified polymorphic DNA (RAPD) markers were used to detect polymorphism among five breeds of chicken i.e. White Leghorn and Rhodes Island Red (selected for part period egg production and egg mass respectively), Red Cornish and White Plymouth Rock (selected for early body weights) and Kadaknath (native breed). Twelve of the fifty random primers screened yielded distinct polymorphic RAPD profiles. Of the total 96 fragments amplified, about 25% showed polymorphism. Using the RAPD data matrix, the within population and between population genetic similarity was estimated. The selected improved breeds showed higher within population genetic similarity in comparison to the native breed. The two meat type breeds showed a high level of genetic similarity between themselves. The White Leghorn breed showed a low genetic similarity with other breeds. The native breed showed highest similarity with Rhodes Island Red. The dendogram was constructed to show phylogenetic relationship among these breeds. As expected, the genetic distances were lowest within similar type breeds and were highest between dissimilar type breeds. The results indicated the effectiveness of RAPD in detecting polymorphism between chicken populations and their applicability in population studies and establishing genetic relationships among the chicken populations.

Animals↗
PubMed1997

Bilateral craniotomies for blunt head trauma.

Development of delayed or recurrent intracranial hematomas requiring reexploration or a secondary craniotomy is well known. Patients with bilateral pathology requiring bilateral craniotomies as the initial emergency operative intervention, however, are uncommon. The lack of available literature and the large volume of head trauma seen at our institution prompted us to analyze the retrospective data on blunt head injury requiring bilateral craniotomies. Twenty patients underwent bilateral craniotomies at the University of Miami/Jackson Memorial Medical Center between January 1986 and June 1994. Ages ranged from 18 to 85 years. Mechanism of injury included motor vehicle crash (n = 4), pedestrian hit by automobile (n = 4), assault (n = 8), fall from height (n = 3), and unknown (n = 1). Epidural hematomas, acute subdural hematomas, contusions, and intracerebral hematomas were seen in varying combinations. The preoperative Glasgow Coma Scale (GCS) score ranged from 4 to 14, with a mean of 8.8 (+/-0.82 SE). Sixteen of the 20 patients survived and were discharged from the hospital. The survivors' Rancho Los Amigos Scale score on discharge ranged from 2 to 8, with a mean of 6.1 (+/-0.45 SE). A Fisher's exact test was performed to compare the outcome between the patients with mild (GCS score 13-15) to moderate (GCS score 9-12) head injury and those with severe (GCS score 4-8) head injury. It showed a statistically higher frequency of death in the severe category (p < 0.05). In conclusion, the outcome of patients with bilateral pathology requiring emergency bilateral craniotomy at initial treatment correlated well with their GCS scores at initial presentation.

Adolescent↗
PubMed1996

Triorganosilicon (IV) compounds: synthesis, structural study, and biological activity.

A few coordination compounds of silicon (IV) have been synthesized by the interaction of trimethyl- and triphenyl-chlorosilane with nitrogen-sulphur donor ligands. These compounds are monomeric, as indicated by molecular weight determination, and they behave as nonelectrolytes in dry DMF. From the electronic, infrared, 1H, and 13C NMR spectral results, it has been concluded that in these compounds, silicon is penta-coordinated in a trigonal bipyramidal environment. An assessment of biological activity of these compounds has shown that some of them are very active against P. mirabilis and others against S. viridans bacteria, while all of them show good fungicidal action against F. oxysporum, A. alternata, and A. niger.

Alternaria↗
PubMed1995

Unsymmetrical borole complexes as biocides: synthetic, structural and biological aspects.

Triisopropoxyborane on treatment with catechol in equimolar ratio in excess of benzene affords the formation of 2-isopropoxybenzo-1,3-dioxa-2-borole [OC6H4OB(OPri)]. The interaction of [OC6H4OB(OPri)] with benzothiazolines, prepared by the condensation of [1-(2-thienyl)ethanone], [1-(2-pyridinyl)ethanone], [1-(2-furanyl)ethanone], and [1-(2-naphthenyl)ethanone] with 2-mercaptoaniline, yields complexes that have B--O, B--S, and B<--N bonds. The unsymmetrical borole complexes were subjected to microestimations and spectral analyses comprised of UV, IR, proton-1, boron-11, and carbon-13 nuclear magnetic resonance studies. The spectral studies point to a tetracoordinated environment around boron because the stereochemically active lone pair is also included in the coordination sphere. X-ray powder diffraction of a representative complex also has been carried out. In the quest for better fungicides and bactericides, studies were conducted to assess the growth-inhibiting potential of the synthesized complexes along with the ligands against various fungal and bacterial strains. The studies demonstrate that the concentrations reach levels that are sufficient to inhibit and kill the pathogens. Furthermore, the results achieved from biological activity also have been compared with the conventional fungicide, Bavistin, and conventional bactericide, Streptomycin.

Anti-Bacterial Agents↗
PubMed1993

Malignant schwannoma of the cerebellum: case report.

A case of malignant cerebellar schwannoma is presented in a woman aged 61 years. A malignant schwannoma of the cerebellum has not been previously reported in the literature. The histological, immunocytological, and ultrastructural properties suggested that this lesion was a malignant, partially epithelioid schwannoma.

Cerebellar Neoplasms↗
PubMed1993

Spinal intramedullary cavernous angioma in a patient with Down's syndrome.

A rare case of cervical intramedullary cavernous angioma in a 30-year-old man with Down's syndrome is presented. A review of the literature showed this to be the first reported case. Magnetic resonance imaging was diagnostic. A myelotomy was done and multiple biopsies were taken. The patient deteriorated neurologically and later died due to severe chest infection. The presentation, management and prognosis of this condition are discussed.

Adult↗