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Biomedical subjects

A Kumar

Publications and source records attributed to A Kumar.

At least 325 records · Page 18Linked to original sources

Immobilization of hormones for drug targeting.

Biological active compounds such as insulin, heparin, progesterone and labeled-LH were entrapped in glutaraldehyde cross-linked bovine serum albumin (BSA) and human serum albumin (HAS) microspheres. Studies were carried out for their binding capacity and biodegradability using new proteolytic enzymes. Effects of proteolytic enzymes such as trypsin, chymotrypsin, papain and pronase-E on microspheres were studied in order to understand the biodegradability of the cross-linked proteins. It has been observed that labeled-LG was entrapped 60% in BSA and HAS microspheres. Labelled-LH-BSA, Labelled-LH-HAS and insulin microspheres were injected into mice and rabbits. It was observed that these cross-linked microspheres were biodegradable and the process appeared to be slow one, useful for sustained release of hormones. It was also observed that these albumin microspheres exhibit fluorescence at 495 nm.

Animals↗

Graphically-enabled integration of bioinformatics tools allowing parallel execution.

Rapid analysis of large amounts of genomic data is of great biological as well as medical interest. This type of analysis will greatly benefit from the ability to rapidly assemble a set of related analysis programs and to exploit the power of parallel computing. TurboGenomics, which is a software package currently in its alpha-testing phase, allows integration of heterogeneous software components to be done graphically. In addition, the tool is capable of making the integrated components run in parallel. To demonstrate these abilities, we use the tool to develop a Web-based application that allows integrated access to a set of large-scale sequence data analysis programs used by a transposon-insertion based yeast genome project. We also contrast the differences in building such an application with and without using the TurboGenomics software.

Computational Biology↗

cAMP increases the expression of human angiotensinogen gene through a combination of cyclic AMP responsive element binding protein and a liver specific transcription factor.

Angiotensinogen is the glycoprotein precursor of one of the most potent vasoactive hormones angiotensin-II which plays an important role in the regulation of blood pressure. We show here that the promoter activity of reporter constructs containing human angiotensinogen promoter is increased by cAMP treatment on transient transfection in HepG2 cells. We have identified a composite cAMP responsive element, located around 840 bases upstream from the transcriptional initiation site, in the promoter of human angiotensinogen gene. This element is recognized by members of CREB/ATF as well as C/EBP family of transcription factors. Another C/EBP binding site that is not recognized by CREB is located 10 bases upstream from this site. We show that co-transfection of CREB increases the promoter activity of reporter constructs containing human angiotensinogen gene promoter attached to the CAT gene. We also show that co-transfection of DBP (which is a member of C/EBP family of transcription factors) increases promoter activity of these reporter constructs.

Activating Transcription Factor 1↗

Molecular signaling in pathogenicity and host recognition in smut fungi taking Karnal bunt as a model system.

Karnal bunt of wheat, incited by a phytopathogen Tilletia indica (Syn. Neovossia indica) is a floret infecting disease. In the floral tissues fungus proliferates and produces massive amount of black spores. In smut fungi, belonging to order Ustilaginales, communication between cells is necessary to regulate growth, differentiation and monokaryotic to dikaryotic transition during pathogenic and sexual development. Neighbouring cells are able to communicate with each other by direct cell to cell contact through plasma membrane bound signaling molecules or through formation of gap junctions and alternatively through secretion of chemical signals if cells are some distance away. Current research efforts toward understanding of pathogenic and sexual development in phytopathogenic fungi, offer a number of opportunities. These include the analysis of molecular signal(s) for direct contribution of sexual interactions to ability of smut and bunt pathogens to cause disease. These efforts will provide not only to explore the mechanisms of pathogenesis, but also to enhance knowledge of basic cellular biology of an economically important group of fungi.

Cell Communication↗

Pre- and extra-marital heterosexual behaviour of an urban community in Rajasthan, India.

A study conducted among the teachers of senior secondary schools of a city in Rajasthan state to know the magnitude of pre- and extra-marital heterosexual practices and some related characteristics revealed that one third of unmarried and one fifth of married males had experienced pre-marital sex. The same for unmarried and married females was 11.8 per cent and 1.5 per cent, respectively. The prevalence of extra-marital heterosexual act among married males was 15.5 per cent. One out of ten married males reported to have had both pre- and extra-marital sex. A male having pre-marital sex was 15 times more likely to have extra-marital sex. Friends, acquaintances and relatives were the important sexual partners while role of commercial sex workers was negligible. The study reports that heterosexual act with person other than the legal spouse is very much prevalent among this group of middle class professionals. This situation is conducive for the spread of HIV infection among general population and may adversely influence the sexual attitudes of students. The study, therefore, suggests that, besides intensifying the health education on HIV/AIDS, serious considerations about the sexual behaviours of school teachers are needed.

Adult↗

Metallothionein induced by cadmium or zinc inhibits lipid peroxidation in rats exposed to dimethylnitrosamine.

Dimethylnitrosamine (N-nitrosodimethyamine) is a potent inducer of microsomal lipid peroxidation in the liver and kidneys. The results of this study show that prior exposure of adult rats to cadmium or zinc antagonises the effect of dimethylnitrosamine on lipid peroxidation by inducing increased metallothionein synthesis. Increased concentration of reduced glutathione (GSH) in the liver and kidney of rats pre-treated with cadmium or zinc and exposed to dimethylnitrosamine suggests that metallothionein inhibits oxidative stress. The presented results have been corroborated by findings that exposure of adult rats to cadmium or zinc may activate genes for metallothionein and glutathione-S-transferase, the protective proteins against oxidative stress.

Animals↗

Enhancement of seed oil content by expression of glycerol-3-phosphate acyltransferase genes.

Arabidopsis thaliana was transformed with a plastidial safflower glycerol-3-phosphate acyltransferase (GPAT) and an Escherichia coli GPAT. The genes were used directly and in modified forms with, as applicable, the plastidial targeting sequence removed, and with an endoplasmic reticulum targeting sequence added. Seeds of plants transformed using only the vector were indistinguishable in oil content from wild-type control plants. All other gene constructs increased seed oil content. The unmodified safflower gene (spgpat) produced oil increases ranging from 10 to 21%. On average, the greatest increase (+22%) was observed in seeds of transformants carrying the spgpat with the targeting peptide removed. The E. coli plsB gene increased seed oil content by an average of 15%.

Arabidopsis↗

The therapeutic potential of interleukin 10 in infection and inflammation.

Interleukin 10 (IL-10), a cytokine with inhibitory activity on inflammation and cell-mediated immune responses, holds enormous potential for the treatment of inflammatory and autoimmune disorders. In addition, IL-10 has also been implicated in the immunopathogenesis of a number of infectious diseases through the use of IL-10 knock-out or IL-10 transgenic mouse models. In this review, we delineate infectious and inflammatory conditions in which IL-10 has shown potential for therapeutic manipulation. Specifically, we review the role of IL-10 in human endotoxemia/sepsis and in HIV infection, conditions for which preliminary phase I trials have recently been undertaken. It is suggested that the therapeutic potential of IL-10 to selectively ameliorate human infectious and inflammatory processes can be realized through a careful selection of the clinical conditions in which patients are undergoing concomitant treatment with anti-microbial regimens.

Animals↗

Patient-reported complications after cryoablation therapy for prostate cancer.

To define the patient-reported complications after cryoablation therapy for prostate cancer and to compare these results to previously published patient-reported complications for radical prostatectomy and external beam irradiation. A questionnaire similar to previously published patient-reported complication studies was sent to the first 290 patients treated by cryoablation therapy at our Institution. The questionnaire was returned by 267 patients. Forty-four patients were excluded from analysis because of prior irradiation, transurethral prostatectomy, or cryoablation, resulting in a study group of 223 patients. Of the 208 patients with good urinary control preoperatively, 9 (4.3%) patients used incontinence pads after cryoablation. Seven of the 8 patients who used one pad daily reported leakage of only a few drops. Impotency, defined as an inability to obtain erections adequate for vaginal penetration, occurred in 85% of men who were potent preoperatively. Urethrorectal fistula occurred in 1 patient (0.4%). Bladder outlet obstruction caused by stricture of sloughed necrotic prostatic tissue required dilation or transurethral resection in 10% of patients. Scrotal swelling, penile tingling, and pelvic pain occurred in 18, 15, and 12% of patients, respectively; typically, these resolved spontaneously within 3 months. Patient-reported complications for cryoblation compared favorably to those reported for radical prostatectomy and external beam irradiation. Patient satisfaction was high; 96% of patients reported that they would choose cryosurgery as a treatment option again.

Aged↗

Analgesic and anti-inflammatory effects of phosphodiesterase inhibitors.

The aim of the present study was to investigate the role of phosphodiesterase (PDE) enzyme inhibitors namely rolipram and theophylline in pain and inflammation in experimental animals. Rolipram, a selective PDE IV inhibitor and theophylline a nonspecific PDE inhibitor exerted dose dependent analgesic and anti-inflammatory effect against acetic acid-induced writhing in mice and carrageenan-induced paw edema in rats, respectively. Nimesulide (1, 2 mg/kg) produced significant anti-inflammatory effect. Further, nimesulide (0.5 mg/kg) potentiated analgesic effect of rolipram but it failed to modulate the anti-inflammatory effect of PDE inhibitors. Present study suggests that PDE enzymes might be playing a role in nociceptive and inflammatory responses in animals.

Abdominal Pain↗

Modulation of antigenicity of mycelial antigens during developmental cycle of Karnal bunt (Tilletia indica) of wheat.

Indirect enzyme linked immunosorbent assays (ELISA) were developed using polyclonal antibodies against soluble cytoplasmic (SCA) and insoluble cell wall antigens (ICWA) for monitoring modulation of mycelial antigens during growth cycle of T. indica. With SCA, continuous decrease in ELISA reactivity was observed in maturing fungus cultures, suggesting that SCA were expressed predominantly during early vegetative phase and their decreasing role was apparent as the fungus matures possibly towards sporogenous mycelium. In case of ICWA, the reaction profile showed an increase up to exponential phase of growth probably due to increase in the cell division and branching of mycelium. But later, ICWA antibody reactivity was decreased which may be due to conversion of mycelial phase to sporogenous phase, a quiescent stage of growth. Characterization of changes in antigenic configuration during developmental cycle of Tilletia indica by these antibodies could prove to be useful in identification of developmentally related and virulence marker(s).

Antigens, Fungal↗

Occurrence of enterotoxigenic Aeromonas species in foods.

Out of a total of 246 food samples of animal origin screened for isolation of Aeromonas spp., 33 (13.41%) were positive for these organisms. Maximum positivity was shown by the samples from fish (28.57%), followed by poultry meat (16.67%), poultry eggs (12.50%), goat meat (12%), buffalo meat (7.69%) and cow milk (5.56%). A. hydrophila was the predominant species (51.52%) followed by A. sobria (39.39%) and A. caviae. Of these, 70.59% A. hydrophila, 69.23% A. sobria and 33.33% A. caviae showed enterotoxigenic reaction in mouse paw oedema test.

Aeromonas↗

Dengue/DHF: an emerging disease in India.

Dengue/DHF is an emergent disease in India and some parts of country are endemic and periodically contributing annual outbreaks of dengue/DHF. Dengue infection manifests as undifferentiated fever, dengue haemorrhagic fever (DHF) which leads to hospitalization large number of people in a localized area. There is high mortality and morbidity associated with the onset of each dengue outbreak leading to great socio-economic impact. The prevention and control of dengue outbreak depends upon the proper monitoring of the disease case through disease surveillance so as to ensure timely management of cases. Vector surveillance helps in the proper and timely implementation of emergency control measures against dengue vector i.e. Aedes aegypti. There is an urgent need for an effective diagnostic strategy for early diagnosis to shorten the illness duration, hospitalization time and the associated complications.

Aedes↗

Prevalence of enterotoxigenic motile aeromonads in children, fish, milk and ice-cream and their public health significance.

Motile aeromonads, which have been implicated as causative agents of human gastroenteritis, meningitis. endocarditis and osteomyelitis, were isolated from fish, pasteurized and flavored milk and ice creams. Forty-five isolates of Aeromonas from diarrheic children (100) and 285 food samples comprising of fish (100), milk (85) and ice creams (100) were identified as A. hydrophila (21), A. sobria (16) and A. caviae (8). Five of these 45 isolates of Aeromonoas (3 A. sobria, 2 A. hydrophila) were from fecal samples of diarrheic children under five years of age. Twenty-six of these 45 isolates were found to be enterotoxin producing by ligated rabbit ileum loop technique. Isolation of enterotoxigenic motile aeromonads from food as well as diarrheic children have great public health significance which will be further discussed.

Aeromonas hydrophila↗