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1.
Arch Comput Methods Eng ; 29(2): 975-1007, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35342283

RESUMO

In this world of big data, the development and exploitation of medical technology is vastly increasing and especially in big biomedical imaging modalities available across medicine. At the same instant, acquisition, processing, storing and transmission of such huge medical data requires efficient and robust data compression models. Over the last two decades, numerous compression mechanisms, techniques and algorithms were proposed by many researchers. This work provides a detailed status of these existing computational compression methods for medical imaging data. Appropriate classification, performance metrics, practical issues and challenges in enhancing the two dimensional (2D) and three dimensional (3D) medical image compression arena are reviewed in detail.

2.
J Phys Chem B ; 113(26): 8983-92, 2009 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-19518060

RESUMO

Studies on the structure and stability of peptides and proteins during l-->d configurational change are certainly important for the designing of peptides with new biological activity and protein engineering. The l-->d amino acid (d AA) changes have been observed in aged proteins such as collagen. Hence, in this study, an attempt has been made to explore the effect of the replacement of l amino acid (l AA) in the model collagen-like peptides with d AA and the origin of structural stability (destability) has been traced using the molecular dynamics (MD) method employing the AMBER force field. Our results reveal that the substitution of d AA produces a large local disruption to the triple-helical structure. Formation of a kink (bulge) at the site of substitution is observed from the detailed analysis of MD trajectory. However, this local perturbation of kinked helix changes the direction of the helices and affects the relative orientation of the respective AA residues for helix-helix interaction, enough to affect the overall stability of the model collagen-like peptide. The destabilization energy per d Ala substitution is 7.87 kcal/mol, which is similar to the value for the Gly-->Ala mutation in collagen. Since the Gly-->Ala mutation is involved in genetic disorders such as osteogenesis imperfecta (OI), the l-->d configurational change may produce a similar effect on collagen.


Assuntos
Aminoácidos/química , Colágeno/química , Modelos Moleculares , Sequência de Aminoácidos , Análise por Conglomerados , Ligação de Hidrogênio , Estabilidade Proteica , Estrutura Secundária de Proteína , Estereoisomerismo , Termodinâmica
3.
Eur J Med Chem ; 135: 434-446, 2017 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-28475971

RESUMO

Two mononuclear copper (II) terpyridine complexes namely, [Cu(Btptpy) (ClO4)](ClO4) 1, and [Cu(Bttpy) (ClO4)](ClO4) 2, (Btptpy (L1) = 4'-(Benzothiophene)-2,2':6',2″-terpyridine, Bttpy (L2) = 4'-(Benzylthiazolyl)-2,2':6',2″-terpyridine) have been synthesized and characterized. Single crystal X-ray diffraction shows that, both ligands belong to monoclinic crystal system with space group P21/c (L1) and P21/n (L2). Absorption spectral titration, DNA melting study, circular dichroism and viscosity measurement reveal that, complex 1 and 2 bind with DNA through intercalation. In addition, interaction between the two copper (II) complexes and bovine serum albumin (BSA) has been studied by fluorescence titration, circular dichroism and their protease activity has been investigated using SDS-PAGE gel electrophoresis. Agarose (AGE) and SDS-PAGE gel electrophoresis reveals both complexes have good nucleolytic and proteolytic property in the presence of additive hydrogen peroxide. Both complexes shows remarkable cytotoxic property against triple negative CAL-51 human breast cancer cell line and hepatocellular carcinoma (HepG2) cancer cell lines and bears very less cytotoxicity towards liver normal cell line (Changs). DCF-DA and TBRAS assay also supported that complex 1 and 2 induces elevated level of reactive oxygen species (ROS) and oxidative stress in cancer cells than normal cell line. Furthermore, FACS analysis confirms complex 1 and 2 brings apoptosis by growth phase cell cycle arrest.


Assuntos
Antineoplásicos/farmacologia , DNA/química , Compostos Organometálicos/farmacologia , Soroalbumina Bovina/química , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Cobre/química , Cobre/farmacologia , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células Hep G2 , Humanos , Estrutura Molecular , Compostos Organometálicos/síntese química , Compostos Organometálicos/química , Piridinas/química , Piridinas/farmacologia , Relação Estrutura-Atividade , Tiazóis/química , Tiazóis/farmacologia , Tiofenos/química , Tiofenos/farmacologia
4.
J Pharm Bioallied Sci ; 7(Suppl 1): S296-300, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26015737

RESUMO

To identify the role of dietary habits (type of diet, skipping meals, snacking in-between meals and frequency of visits to fast food restaurants) in caries occurrence and severity. To explore the correlation between frequency of intake of selected foods and dental caries. A cross-sectional study was carried out on adolescent children (n = 916) of age 13-19, following a two-stage random sampling technique. Data were collected using a pretested questionnaire. Questionnaire included demographic details, dietary habits of children and food frequency table that listed selected food items. The dependent variable-dental caries was measured using the decayed, missing, filled teeth (DMFT) index. The prevalence of dental caries in this study population was 36.7% (95% confidence interval: 33.58-39.82). The mean DMFT was 1.01 (±1.74). No statistically significant difference found between caries occurrence and type of diet (P = 0.07), skipping meals (P = 0.86), frequency of eating in fast food stalls (0.86) and snacking in between meals (0.08). Mean DMFT values were higher among nonvegetarians and among children who had the habit of snacking in between meals. Frequency of intake of selected food items showed that mean frequency intake of carbonated drinks and confectionery was higher among children who presented with caries when compared to caries-free children (P = 0.000). Significant correlation found between mean DMFT and mean frequency intake of carbonated drinks and confectionery. Odds ratios were calculated for the same for frequency ≥4 times/day for confectionery and ≥4/week for carbonated drinks and results discussed. Frequent intake of carbonated drinks and confectionery is harmful to oral health that eventually reflects on general health. Educating the adolescent children on healthy dietary habits should be put in the forefront.

5.
J Clin Diagn Res ; 8(12): JC10-2, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25653973

RESUMO

OBJECTIVE: To explore the influence of pocket money on Dental Caries and Body Mass Index. MATERIALS AND METHODS: A cross-sectional study was conducted wherein urban adolescent schoolchildren of age 13-18(n=916) were selected by two stage random sampling technique. Dental caries was measured using the DMFT Index. The children's nutritional status was assessed by means of anthropometric measurements. Body Mass Index using weight and height of children was evaluated using the reference standard of the WHO 2007. RESULTS: RESULTS showed that 50% of children receive pocket money from parents. The average amount received was Rs. 360/month. There was a significant correlation between age and amount of money received (r=0.160, p=.001). The average amount received by male children was significantly higher (Rs. 400) when compared to female children (Rs. 303). It was observed that income of the family (>30,000 Rs./month) and socioeconomic status (Upper class) was significantly dependent on the amount of money received by children (p<0.05). There was no significant difference in the occurrence of caries among children receiving pocket money or not. When BMI categories and pocket money were considered, statistically significant difference was seen among overweight and obese and normal weight children (p<.05). Higher proportion (40.1%) of overweight and obese adolescent children frequented the fast food restaurants every week when compared to the underweight (31.7%) and normal weight children (29.9%). CONCLUSION: Adolescent children receiving pocket money from parents could influence their eating habits in turn affect general health. Parents and teachers should motivate children on healthy spending of their pocket money.

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