Search PubMed⌕ Search

Biomedical subjects

Nitin Gupta

Publications and source records attributed to Nitin Gupta.

At least 19 recordsLinked to original sources
PubMed2006

Defining the transcriptome of accelerated and replicatively senescent keratinocytes reveals links to differentiation, interferon signaling, and Notch related pathways.

Epidermal keratinocytes (KCs) undergo highly orchestrated morphological and molecular changes during transition from proliferative compartment into growth arrested early and late differentiation layers, prior to dying in outermost cornified layers of normal skin. Creation of stratum corneum is vital to barrier function protecting against infection. Transcriptional events in KCs regulating complex processes of differentiation and host defense required to maintain constant epidermal thickness and resistance to infection in either young or aged skin are largely unknown. Furthermore, as terminal differentiation is characterized by irreversible loss of replicative potential culminating in dead layers at the skin surface, this process may be viewed as a form of senescence. However, a complete transcriptional profile of senescent (SN) human KCs has not been previously defined to permit delineation of molecular boundaries involving differentiation and senescence. To fill this void, we utilized global transcriptional analysis of KCs maintained in vitro as either cultures of proliferating (PR) cells, early and late confluent (LC) (accelerated senescence) cultures, or KCs undergoing replicative senescence. Global gene expression profiling revealed early confluent (EC) KCs were somewhat similar to PR KCs, while prominent differences were evident when compared to LC KCs; which were also distinct from replicatively SN KCs. While confluent KCs have in common several genes regulating differentiation with replicatively SN KCs, the latter cells expressed elevated levels of genes involved in interferon signaling and inflammatory pathways. These results provide new insights into cell autonomous transcriptional-based programs operative within KCs contributing to replicative senescence, with partial sharing of genes involved in differentiation. In addition, regulation of KC senescence may involve participation of interferon signaling pathways derived from the important role of KCs in protecting skin from infection. Integrating all of the transcriptional data revealed a key role for Notch receptor mediated signaling in the confluency induced differentiation phenotype using this model system.

Apoptosis↗
PubMed2006

Comparative study of neuropsychological correlates in schizophrenia with onset in childhood, adolescence and adulthood.

Childhood onset schizophrenia (COS) patients have marked neuropsychological deficits in areas of attention, working memory and executive functions. Similar deficits have been found in studies on Adolescent onset (AdOS) and Adult onset schizophrenia (AOS). In this study we compared the neuropsychological profile of COS with AdOS and AOS to test the hypothesis that earlier the onset greater is the severity of illness and greater are the neuropsychological deficits. A sample of 15 patients of COS was compared with 20 patients each of AdOS and AOS group. Assessment of neuropsychological profile was done using standard neuropsychological battery for Indian population. Nahor Benson Test and Bender Visual Motor Gestalt Test were used to assess perceptuomotor functioning. COS patients showed significantly greater deficits on scales of IQ, memory and perceptuomotor skills as compared to AdOS that in turn had greater deficits than AOS. The persistence of differences across the three groups inspite of controlling for education and age suggest that these deficits may have been present even before the onset of illness and was not the result of poor academic achievements. These findings also point towards a brain damage in schizophrenia that occurs on a continuum of severity with COS being the most virulent, AOS being the least and AdOS falling in between these two extremes.

Adolescent↗
PubMed2006

Shared obsessive-compulsive disorder.

BACKGROUND: Shared psychotic disorder (folie à deux) is an uncommon entity reported mainly in the context of delusions. Obsessions and compulsions occur very rarely as shared psychopathology. MATERIAL AND METHODS: We present two sisters who manifested shared obsessive-compulsive disorder. RESULTS: Both sisters were managed in keeping with their shared obsessive-compulsive disorder leading onto a similar pattern of response. CONCLUSIONS: Shared obsessions could represent the continuum concept of obsessions and delusions, and their relationship needs to be evaluated in greater detail.

Adult↗
PubMed2006

Urethral stricture assessment: a prospective study evaluating urethral ultrasonography and conventional radiological studies.

OBJECTIVE: To evaluate the accuracy of urethral ultrasonography (sono-urethrography, SUG) in determining the length of anterior urethral strictures, and for predicting the degree of spongiofibrosis. PATIENTS AND METHODS: In all, 52 patients with anterior urethral strictures detected on retrograde urethrography (RUG) were also examined using SUG, to assess the stricture location, length and degree of spongiofibrosis. The findings of both procedures were then compared with the operative findings. RESULTS: The mean (sd) stricture length on RUG, SUG and at surgery was 2 (0.8), 3.8 (1.4) and 3.5 (1.6) cm, respectively. The mean length on SUG was closer to that at surgery. Spongiofibrosis was detected by SUG with an overall accuracy of 42%, 56% and 83% for mild, moderate and severe degrees of fibrosis, respectively. There were no significant complications during the procedure. CONCLUSION: SUG is more accurate for evaluating the length of anterior urethral strictures than RUG, and gives additional information about spongiofibrosis.

Fibrosis↗
PubMed2005

Evolution and similarity evaluation of protein structures in contact map space.

Prediction of fold from amino acid sequence of a protein has been an active area of research in the past few years, but the limited accuracy of existing techniques emphasizes the need to develop newer approaches to tackle this task. In this study, we use contact map prediction as an intermediate step in fold prediction from sequence. Contact map is a reduced graph-theoretic representation of proteins that models the local and global inter-residue contacts in the structure. We start with a population of random contact maps for the protein sequence and "evolve" the population to a "high-feasibility" configuration using a genetic algorithm. A neural network is employed to assess the feasibility of contact maps based on their 4 physically relevant properties. We also introduce 5 parameters, based on algebraic graph theory and physical considerations, that can be used to judge the structural similarity between proteins through contact maps. To predict the fold of a given amino acid sequence, we predict a contact map that will sufficiently approximate the structure of the corresponding protein. Then we assess the similarity of this contact map with the representative contact map of each fold; the fold that corresponds to the closest match is our predicted fold for the input sequence. We have found that our feasibility measure is able to differentiate between feasible and infeasible contact maps. Further, this novel approach is able to predict the folds from sequences significantly better than a random predictor.

Amino Acid Sequence↗
PubMed2005

Stigma experience in skin disorders: an Indian perspective.

Dermatologic disorders generally have a major impact on patients' daily activities, psychologic and emotional state, and social relationships. The intensity of impact of skin disease on an individual person is extremely variable, however, and depends on natural history of the disorder; the patient's demographic characteristics, personality, character, and value; the patient's life situation; and the attitudes of society. Social stigma toward dermatologic disorders in the Indian society is quite widespread, especially toward leprosy. Dermatologists are expected to consider quality of life issues along with social aspects, nature of disorder, efficacy, and tolerability of various therapeutic options to optimize relief and comfort to their patient.

Cultural Characteristics↗
PubMed2005

Eyelid disease.

Explore the source record for details and available documents.

Corneal Diseases↗
PubMed2005

Can the need for palliative transurethral prostatic resection in patients with advanced carcinoma of the prostate be predicted?

PURPOSE: To identify the factors predicting the need for palliative transurethral resection of the prostate (channel TURP) in patients with advanced carcinoma of the prostate (CAP) receiving androgen ablation therapy. PATIENTS AND METHODS: From January 1996 to January 2004, 203 patients with advanced CAP were treated by androgen ablation. Patients presenting with retention were catheterized initially, and those (N = 12) who failed a catheter-free trial and had immediate channel TURP were excluded. The remaining 191 patients were followed every 3 months (mean 35.5 months, range 6-92 months). Patients requiring channel TURP (group 1; N = 42 [22%]) during follow-up were compared with those who did not (group 2) for predictive factors, viz. retention of urine, serum prostate specific antigen (PSA) concentration, Gleason sum, prostate size, and bony metastasis at presentation. RESULTS: Channel TURP was performed at a mean of 21 months (range 3-72 months). The mean Gleason sum in this group was 7.88, whereas it was 7.29 in group 2 (P = 0.013). Retention at presentation was significantly more common in group 1 (N = 26; 61.9%) than in group 2 (N = 46; 30.8%; P = 0.001). Patients who did not present with retention and had Gleason sums < or =7 (N = 32) did not require channel TURP. Of the 14 patients who voided successfully after a catheter-free trial but had Gleason sums of >7, 71.4% required channel TURP. Other factors were not found to be significantly different in the two groups. CONCLUSION: High Gleason sum and retention at presentation are significant factors predictors of the need for channel TURP during follow-up in patients with advanced CAP receiving androgen ablation therapy.

Aged↗
PubMed2005

FASSM: enhanced function association in whole genome analysis using sequence and structural motifs.

We present an algorithm to detect remote homology, which arises through circular permutation and discontinuous domains. It is also helpful in detecting small domain proteins that are characterized by few conserved residues. The input to the algorithm is a set of multiply aligned protein sequence profiles. This method, coded as FASSM, examines the sequence conservation and positions of protein family signatures or motifs for the annotation of protein sequences and to facilitate the analysis of their domains. The overall coverage of FASSM is 93% in comparison to other validation tools like HMM and IMPALA. The method is especially useful for difficult relationships such as discontinuous domains during whole-genome surveys and is demonstrated to perform accurate family associations at sequence identities as low as 15%.

Algorithms↗
PubMed2004

Synthesis of new 6-alkylvinyl/arylalkylvinyl substituted 1,2,4-trioxanes active against multidrug-resistant malaria in mice.

3-Alkyl/arylalkyl substituted 2-butenols 9, 10, 23a-d undergo regiospecific photooxygenation to furnish beta-hydroxyhydroperoxides 11, 12, 24a-d, respectively, in reasonable yields. Acid catalyzed condensation of 11, 12, 24a-d with various ketones furnish new 1,2,4-trioxanes 13-18, 25a-d, 26a-d, 27a-d in good yields. Several of these trioxanes show promising antimalarial activity against multidrug-resistant Plasmodium yoelii in mice by oral and intramuscular routes.

Animals↗
PubMed2004

Coupled folding-binding versus docking: a lattice model study.

Using a simple hydrophobic/polar protein model, we perform a Monte Carlo study of the thermodynamics and kinetics of binding to a target structure for two closely related sequences, one of which has a unique folded state while the other is unstructured. We obtain significant differences in their binding behavior. The stable sequence has rigid docking as its preferred binding mode, while the unstructured chain tends to first attach to the target and then fold. The free-energy profiles associated with these two binding modes are compared.

Journal Article↗
PubMed2003

Geraniol-derived 1,2,4-trioxanes with potent in-vivo antimalarial activity.

Geraniol, an abundantly available naturally occurring allylic alcohol, has been used as a starting material to prepare a series of 6-[alpha-(3'-aryl-3'-hydroxypropyl)vinyl]-1,2,4-trioxanes. Some of these novel trioxanes have shown very promising antimalarial activity against multi-drug resistant Plasmodium yoelii in mice by both intramuscular (im) and oral routes.

Acyclic Monoterpenes↗