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1.
Angew Chem Int Ed Engl ; 63(23): e202401368, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38584127

RESUMEN

Polaritonic chemistry is emerging as a powerful approach to modifying the properties and reactivity of molecules and materials. However, probing how the electronics and dynamics of molecular systems change under strong coupling has been challenging due to the narrow range of spectroscopic techniques that can be applied in situ. Here we develop microfluidic optical cavities for vibrational strong coupling (VSC) that are compatible with nuclear magnetic resonance (NMR) spectroscopy using standard liquid NMR tubes. VSC is shown to influence the equilibrium between two conformations of a molecular balance sensitive to London dispersion forces, revealing an apparent change in the equilibrium constant under VSC. In all compounds studied, VSC does not induce detectable changes in chemical shifts, J-couplings, or spin-lattice relaxation times. This unexpected finding indicates that VSC does not substantially affect molecular electron density distributions, and in turn has profound implications for the possible mechanisms at play in polaritonic chemistry under VSC and suggests that the emergence of collective behavior is critical.

2.
J Med Syst ; 42(12): 251, 2018 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-30392052

RESUMEN

Meningioma is the one of the most common type of brain tumor, it as arises from the meninges and encloses the spine and the brain inside the skull. It accounts for 30% of all types of brain tumor. Meningioma's can occur in many parts of the brain and accordingly it is named. In this paper, a mixture model based classification of meningioma brain tumor using MRI image is developed. The proposed method consists of four stages. In the first stage, with respect to the cells' boundary, it is necessary to further processing, which ensures the boundary of some cells is a discrete region. Mathematical Morphology brings a fancy result during the discrete processing. Accurate cancer cell nucleus segmentation is necessary for automated cytological image analysis. Thresholding is a crucial step in segmentation..An adaptive binarization technique is an important step for medical image analysis.Finally, a novel hybrid Fuzzy SVM is designed in the classification stage meningioma brain tumor. The tumor classification results of proposed feature extraction with SVM is 74.24%, MM with FSVM is 82.67% and MM with RBF is 62.71% and our proposed method MM with Hybrid SVM is 91.64%.


Asunto(s)
Neoplasias Encefálicas/patología , Procesamiento de Imagen Asistido por Computador/métodos , Meningioma/patología , Máquina de Vectores de Soporte , Neoplasias Encefálicas/diagnóstico por imagen , Lógica Difusa , Humanos , Imagen por Resonancia Magnética/métodos , Meningioma/diagnóstico por imagen
3.
BMC Public Health ; 18(1): 103, 2018 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-29304779

RESUMEN

BACKGROUND: Many interventions have attempted to increase vulnerable and remote populations' access to ORS and zinc to reduce child mortality from diarrhoea. However, the impact of these interventions is difficult to measure. From 2010 to 15, Micronutrient Initiative (MI), worked with the public sector in Bihar, India to enable community health workers to treat and report uncomplicated child diarrhoea with ORS and zinc. We describe how we estimated programme's impact on child mortality with Lives Saved Tool (LiST) modelling and data from MI's management information system (MIS). This study demonstrates that using LiST modelling and MIS data are viable options for evaluating programmes to reduce child mortality. METHODS: We used MI's programme monitoring data to estimate coverage rates and LiST modelling software to estimate programme impact on child mortality. Four scenarios estimated the effects of different rates of programme scale-up and programme coverage on estimated child mortality by measuring children's lives saved. RESULTS: The programme saved an estimated 806-975 children under-5 who had diarrhoea during five-year project phase. Increasing ORS and zinc coverage rates to 19.8% & 18.3% respectively under public sector coverage with effective treatment would have increased the programme's impact on child mortality and could have achieved the project goal of saving 4200 children's lives during the five-year programme. CONCLUSIONS: Programme monitoring data can be used with LiST modelling software to estimate coverage rates and programme impact on child mortality. This modelling approach may cost less and yield estimates sooner than directly measuring programme impact with population-based surveys. However, users must be cautious about relying on modelled estimates of impact and ensure that the programme monitoring data used is complete and precise about the programme aspects that are modelled. Otherwise, LiST may mis-estimate impact on child mortality. Further, LiST software may require modifications to its built-in assumptions to capture programmatic inputs. LiST assumes that mortality rates and cause of death structure change only in response to changes in programme coverage. In Bihar, overall child mortality has decreased and diarrhoea seems to be less lethal than previously, but at present LiST does not adjust its estimates for these sorts of changes.


Asunto(s)
Mortalidad del Niño/tendencias , Diarrea/prevención & control , Soluciones para Rehidratación/uso terapéutico , Sales (Química)/uso terapéutico , Zinc/uso terapéutico , Administración Oral , Preescolar , Diarrea/mortalidad , Humanos , India/epidemiología , Lactante , Modelos Teóricos , Evaluación de Programas y Proyectos de Salud , Sector Público
4.
AIDS Behav ; 16(4): 1054-62, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-21811840

RESUMEN

This study compared rates of HIV-related sexual risk behaviours reported in individual face-to-face (FTFI) and group anonymous polling booth (PBS) interviews in India. In PBS, respondents grouped by gender and marital status answered yes/no questions by putting tokens with question numbers in colour-coded containers. Data were subsequently collated for each group as a whole, so responses were not traceable back to individuals. Male and female PBS participants reported substantially higher rates of pre-marital, extra-marital, commercial and anal sex than FTFI participants; e.g. 11 vs. 2% married males reported paying for sex; 6 vs. 1% unmarried males reported homosexual anal sex.


Asunto(s)
Condones/estadística & datos numéricos , Seropositividad para VIH/epidemiología , Estado Civil/estadística & datos numéricos , Parejas Sexuales , Deseabilidad Social , Adolescente , Adulto , Análisis por Conglomerados , Femenino , Seropositividad para VIH/psicología , Humanos , India/epidemiología , Masculino , Persona de Mediana Edad , Asunción de Riesgos , Muestreo , Parejas Sexuales/psicología , Encuestas y Cuestionarios , Revelación de la Verdad , Adulto Joven
5.
Sex Transm Infect ; 86 Suppl 1: i10-6, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20167724

RESUMEN

BACKGROUND: The HIV epidemic is very heterogeneous at the district level in the four Southern states of India most affected by the epidemic and where transmission is mainly heterosexual. The authors carried out an ecological study of the relationship between high-risk population parameters and HIV prevalence among pregnant women (ANC HIV prevalence). METHODS: The data used in this study included: ANC HIV prevalence available from the National AIDS Control Organization (dependent variable); data on prevalence of HIV and other sexually transmitted infections among female sex workers (FSWs), their clients and high-risk men who have sex with men (HR-MSM) from studies carried out in 24 districts under Avahan; data on clients' volume reported by FSWs and on the size estimates of FSWs and HR-MSM in each district; and census data. The latter two sets of data were used to estimate the percentage of female (male) adults who are FSWs (HR-MSM). The latter was also multiplied by HIV prevalence in FSWs (HR-MSM) to obtain the percentage of HIV-positive FSWs (HR-MSM) in the adult female (male) population. Linear regression was used for statistical analyses. RESULTS: In univariate analyses, HIV (r=0.59, p=0.002) and HSV-2 (r=0.49, p=0.014) prevalence among FSWs and mean number of clients in the last week reported by FSWs (r=0.43, p=0.036) were significant predictors of ANC HIV prevalence. In multivariate analysis, only FSW HIV prevalence remained significant. CONCLUSIONS: This ecological study suggests that there is a link between HIV prevalence among FSWs and the spread of HIV to the general population in Southern India. Such an observation supports the rationale of interventions targeted at the sex industry.


Asunto(s)
Infecciones por VIH/epidemiología , Complicaciones Infecciosas del Embarazo/epidemiología , Adulto , Brotes de Enfermedades , Métodos Epidemiológicos , Femenino , Infecciones por VIH/prevención & control , Infecciones por VIH/transmisión , Homosexualidad Masculina/estadística & datos numéricos , Humanos , India/epidemiología , Masculino , Embarazo , Trabajo Sexual/estadística & datos numéricos , Enfermedades de Transmisión Sexual/epidemiología , Enfermedades de Transmisión Sexual/transmisión
6.
Sex Transm Infect ; 86 Suppl 1: i49-55, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20167731

RESUMEN

BACKGROUND: Avahan, the India AIDS Initiative, is a large-scale targeted intervention. Data on condom use prior to Avahan are unavailable. The authors used a novel method of analysing cross-sectional survey data to 'reconstruct' condom use rates in presurvey years, and to assess the relationship between Avahan and time trends in condom use among female sex workers (FSWs). METHODS: Among FSWs reporting consistent condom use (CCU) with clients in surveys from 21 districts in southern India (n=7358), data on length of time using condoms, and length of time selling sex, were converted into number of FSWs using condoms (numerator) and selling sex (denominator) by year, to give yearly rates of CCU from 2001 to year of survey. Linear regression with generalised estimating equations was used to assess time trends and to compare the rate of increase in condom use before and after Avahan initiation in 2003. RESULTS: In all 21 districts, the rate of increase in CCU from 2001 to time of the surveys was highly significant. Overall CCU increased from 27% (22%) with occasional (regular) clients in 2001, to 76% (68%) in 2006, respectively. The yearly rate of increase in CCU was significantly greater after (slope 2003-2006: 12.7% (12.0%) per year for occasional (regular) clients) than prior to Avahan (slope 2001-2003: 5.1% (5.3%) per year for occasional (regular) clients) implementation (p<0.0001). CONCLUSIONS: The findings indicate a positive relationship between implementation of the Avahan programme and rates of CCU increase among FSW. This method of analysis may be useful in other contexts where preintervention data are lacking.


Asunto(s)
Condones/estadística & datos numéricos , Infecciones por VIH/prevención & control , Sexo Seguro/estadística & datos numéricos , Trabajo Sexual/estadística & datos numéricos , Métodos Epidemiológicos , Femenino , Predicción , Humanos , India , Masculino , Evaluación de Programas y Proyectos de Salud , Factores de Tiempo
7.
Thorax ; 64(12): 1053-61, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19850962

RESUMEN

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a fatal interstitial lung disease characterised by accumulation of activated (myo)fibroblasts and excessive extracellular matrix deposition. The enhanced accumulation of (myo)fibroblasts may be attributed, in part, to the process of transforming growth factor beta1 (TGFbeta1)-induced epithelial-mesenchymal transition (EMT), the phenotypic switching of epithelial to fibroblast-like cells. Although alveolar epithelial type II (ATII) cells have been shown to undergo EMT, the precise mediators and mechanisms remain to be resolved. The objective of this study is to investigate the role of SNAI transcription factors in the process of EMT and in IPF. METHODS: Using quantitative reverse transcription-PCR (RT-PCR), immunofluorescence, immunohistochemistry, western blotting, as well as gain- and loss-of-function studies and functional assays, the role of SNAI1 and SNAI2 in TGFbeta1-induced EMT in ATII cells in vitro was assessed; and the expression of SNAI transcription factors was analysed in experimental and human IPF in vivo. RESULTS: TGFbeta1 treatment increased the expression and nuclear accumulation of SNAI1 and SNAI2, in concert with induction of EMT in ATII cells. SNAI overexpression was sufficient to induce EMT, and small interfering RNA (siRNA)-mediated SNAI depletion attenuated TGFbeta1-induced ATII cell migration and EMT. SNAI expression was elevated in experimental and human IPF and localised to hyperplastic ATII cells in vivo. CONCLUSIONS: The results demonstrate that TGFbeta1-induced EMT in ATII cells is essentially controlled by the expression and nuclear translocation of SNAI transcription factors. Increased SNAI1 and SNAI2 expression in experimental and human IPF in vivo suggests that SNAI-mediated EMT may contribute to the fibroblast pool in idiopathic pulmonary fibrosis.


Asunto(s)
Células Epiteliales/patología , Células Madre Mesenquimatosas/patología , Fibrosis Pulmonar/patología , Factores de Transcripción/fisiología , Adulto , Animales , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/fisiología , Línea Celular , Movimiento Celular/efectos de los fármacos , Células Cultivadas , Modelos Animales de Enfermedad , Células Epiteliales/efectos de los fármacos , Proteínas de la Matriz Extracelular/farmacología , Femenino , Silenciador del Gen , Humanos , Masculino , Células Madre Mesenquimatosas/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Persona de Mediana Edad , Fibrosis Pulmonar/metabolismo , Fibrosis Pulmonar/fisiopatología , ARN Interferente Pequeño/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Factores de Transcripción de la Familia Snail , Factores de Transcripción/metabolismo , Factor de Crecimiento Transformador beta/farmacología
8.
AIDS ; 22 Suppl 5: S117-25, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19098472

RESUMEN

OBJECTIVES: To estimate HIV and sexually transmitted infection (STI) prevalence within the general population of Mysore district, and to examine differences in the distribution of risk factors associated with HIV prevalence stratified by sex. METHODS: A community-based study was conducted in Mysore, Karnataka state, southern India, between October 2005 and November 2006; final sample size 4653. A face-to-face interview was conducted, and blood and urine specimens collected to measure HIV and STI prevalences. Risk factors for HIV among men and women were examined using weighted and clustered logistic regression. RESULTS: Weighted HIV prevalence was 0.8% [95% confidence interval (CI) 0.52-1.09] overall and 0.7% (0.35-1.08) and 0.9% (0.51-1.37) in rural and urban populations, respectively. The prevalence of syphilis, gonorrhoea and chlamydial infection was 2.8% for men and 1.8% for women. In multivariate analysis, higher HIV prevalence was associated with ever having used a condom [odds ratio (OR) 2.75, 95% CI 1.01-7.47] and number of lifetime partners for men (OR 6.9, 95% CI 2.18-21.91). For women, HIV infection was associated with condom use at last sexual intercourse (OR 10.51, 95% CI 2.05-53.79), number of lifetime partners and reporting 'don't know' for whether ever had anal sex (OR 9.10, 95% CI 1.14-72.34). CONCLUSIONS: HIV prevalence in the general population of Mysore was found to be comparable to recent prevalence estimates for Karnataka state, and also similar to recent prevalence estimates from antenatal clinic attenders for the district. Few modifiable risk factors for HIV infection were identified. There is evidence from this study that high-risk behaviour may have been underreported, but the prevalence of STI was generally low.


Asunto(s)
Infecciones por VIH/epidemiología , Adolescente , Adulto , Distribución por Edad , Condones/estadística & datos numéricos , Métodos Epidemiológicos , Femenino , Infecciones por VIH/transmisión , Humanos , India/epidemiología , Masculino , Persona de Mediana Edad , Prevalencia , Asunción de Riesgos , Salud Rural/estadística & datos numéricos , Conducta Sexual/estadística & datos numéricos , Parejas Sexuales , Enfermedades de Transmisión Sexual/epidemiología , Enfermedades de Transmisión Sexual/transmisión , Salud Urbana/estadística & datos numéricos , Adulto Joven
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