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1.
J Mater Chem B ; 12(15): 3786-3796, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38546335

RESUMO

Trypsin, a pancreatic enzyme associated with diseases like pancreatic cancer and cystic fibrosis, requires effective diagnostic tools. Current detection systems seldom utilize macrocyclic molecules and tetraphenyl ethylene (TPE) derivative-based supramolecular assemblies, known for their biocompatibility and aggregation-induced emission (AIE) properties, for trypsin detection. This study presents an enzyme-responsive, AIE-based fluorescence 'Turn-On' sensing platform for trypsin detection, employing sulfated-ß-cyclodextrin (S-ßCD), an imidazolium derivative of TPE (TPE-IM), and protamine sulfate (PrS). The anionic S-ßCD and cationic TPE-IM formed a strongly fluorescent supramolecular aggregation complex in an aqueous buffer. However, PrS suppresses fluorescence because of its strong binding affinity with S-ßCD. The non-fluorescent TPE-IM/S-ßCD/PrS supramolecular assembly system exhibits trypsin-responsive properties, as PrS is a known trypsin substrate. Trypsin restores fluorescence in the TPE-IM/S-ßCD system through the enzymatic cleavage of PrS, correlating linearly with trypsin catalytic activity in the 0-10 nM concentration range. The limit of detection is 10 pM. This work contributes to the development of self-assembled supramolecular biosensors using charged TPE derivatives and ß-cyclodextrin-based host-guest chemistry, offering an innovative fluorescence 'Turn-On' trypsin sensing platform. The sensing system is highly stable under various conditions, selective for trypsin, and demonstrates potential for biological analysis and disease diagnosis in human serum. Additionally, it shows promise for the screening of trypsin inhibitors.


Assuntos
Técnicas Biossensoriais , Etilenos , beta-Ciclodextrinas , Humanos , Corantes Fluorescentes/química , Tripsina
2.
Health Educ Res ; 38(5): 469-489, 2023 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-37207678

RESUMO

We report process evaluation findings from the 'SMART Eating' intervention trial, which significantly improved fat, sugar and salt (FSS), and fruits and vegetables (FVs) intake among adults. Intervention used information technology [short message service (SMS), WhatsApp and website] and interpersonal communication (distribution of SMART Eating kit) and pamphlet for comparison group. Guided by UK Medical Research Council's framework, using embedded mixed-methods design, continuous process evaluation documented fidelity, dose, reach, acceptability and mechanisms. Intervention was implemented as intended, with high reach (91%) in both groups: 'comparison group' (n = 366): inadequate use of pamphlets (46%); 'intervention group' (n = 366): with timely remedial measures to remove implementation/usage barriers, dose of SMS (93%), WhatsApp (89%) and 'SMART Eating' kit (100%) was adequate, but website usage was low (50%); compliance was evident from participants' interactions with the implementor and observations on kit usage. All these might have improved attitude, social influence, self-efficacy and household behaviours, which, in turn, mediated intervention's effect on improving FSS and FV intake. Among poor performers, lack of effect on FV intake was perceived to be related to high cost/pesticides use and FSS intake was related to lack of family support. Low website usage, challenges with WhatsApp messaging and contextual factors (cost, pesticides abuse and family support) need to be considered while designing similar future interventions.


Assuntos
Dieta , Promoção da Saúde , Tecnologia , Adulto , Humanos , Povo Asiático , Comunicação , Projetos de Pesquisa , Cloreto de Sódio na Dieta , Aplicativos Móveis , Envio de Mensagens de Texto
3.
Venereology (Basel) ; 2(1): 30-42, 2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36945363

RESUMO

Transgender women (TGW) in India, especially those who engage in sex work, are at high risk for HIV. Guided by the information-motivation-behavioral skills model and qualitative formative research findings, Sakhi (girlfriend), a 3-week smartphone-based pilot intervention consisting of short videos (one/week) and text messages (two/week), was implemented using a one-group pre- and post-test design to test its efficacy in promoting condom use and HIV testing among TGW (N = 50) who engage in sex work in Chennai. Changes in outcomes were assessed by conducting multivariable analyses using generalized estimating equations. Participants' mean age was 26 years, and the mean monthly income was INR 21700 (USD 292). About one-third completed college, and 96% were HIV-negative. Significant changes in the desired direction were observed in the primary outcomes: condom use - decrease in the engagement of condomless anal sex with male partners (12% to 2%, p < 0.05) and HIV testing - increase in intentions to undergo HIV testing every 6 months (34% to 86%, p < 0.001); and in some of the secondary outcomes: decrease in alcohol use before sex, increase in intentions to use condoms consistently and increase in the well-being score. This study demonstrated the feasibility, acceptability, and preliminary efficacy of the Sakhi intervention and warrants a larger randomized trial among diverse sub-groups in diverse settings.

5.
AIDS Care ; 34(12): 1586-1594, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36062378

RESUMO

Limited data is available on the associations between intersectional stigmas and mental health outcomes among men who have sex with men living with HIV (MSMLH) in India. The minority stress model postulates that sexual stigma contributes to depression through proximal stressors like internalized homonegativity (IHN). Using cross-sectional survey data from 119 MSMLH in 2015/16, we tested whether: (1) sexual stigma and enacted HIV stigma (EHS) are associated with depression; (2) their effects on depression are mediated through IHN and internalized HIV stigma (IHS); and (3) their effects on IHN are mediated through IHS. Significant direct associations were observed between scores on sexual stigma and IHS (ß = .49, 95% CI .27, .70), EHS and IHN (ß = .19, 95% CI .03, .36), and IHS and IHN (ß = .07, 95% CI .03, .12). IHS scores mediated the associations of sexual stigma with depression (ß = .17, 95% CI .07, .27) and IHN scores (ß = .04, 95% CI .004, .07). EHS was not found to be significantly associated with depression or IHN. The findings partially support the minority stress model among MSMLH and highlight the importance of addressing both sexual and HIV-related stigmas to improve mental health of MSMLH, especially by screening for and reducing IHS, IHN and depression.


Assuntos
Infecções por HIV , Minorias Sexuais e de Gênero , Masculino , Humanos , Homossexualidade Masculina/psicologia , Depressão/psicologia , Estudos Transversais , Infecções por HIV/psicologia , Estigma Social , Índia
7.
Indian J Med Res ; 155(1): 123-128, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35859438

RESUMO

Background & objectives: The safety of the ChAdOx1 nCoV-19 vaccine is a cause of concern for many who have been vaccinated. The people have multiple concerns and fear regarding the adverse events of the vaccine. Thus, this study was undertaken to establish the safety profile of ChAdOx1 nCoV-19 Corona Virus Vaccine (Recombinant) among the healthcare professionals. Methods: This was a descriptive cross-sectional survey. After taking clearance from the institutional ethics committee 1500 healthcare professionals, who had their vaccination in the past two weeks were selected. They were provided with an online survey proforma regarding adverse events following immunization (AEFIs) of COVID-19 vaccine developed using google forms with an informed consent form affixed to it. Results: A total of 1036 individuals participated in the study. The mean and median (inter quartile range) age of the participants was 37.7 ±11.25 and 35 (29-46) yr, respectively. Of these, 52.1 per cent were female, 29.3 per cent were doctors, 33.4 per cent were nurses and 9.5 per cent were paramedical staff. Forty six per cent participants experienced one or more minor AEFIs such as pain, tenderness, redness, etc. at the injection site. Fatigue (31.75%), generalized feeling of unwell (28.57%), muscle pain (23.16%) and fever (21.71%) were the most commonly reported systemic AEFIs followed by headache (20.07%), dizziness (10.03%) and joint pains (15.25%). Most of them experienced these AEFIs within 24 h of the first dose of administration. About 42 per cent of the participants took oral antipyretics/analgesics for managing the AEFIs. Interpretation & conclusions: ChAdOx1 nCoV-19 Corona Virus Vaccine was found to be associated with mild local and systemic AEFIs that were more common after the first dose as compared to the second dose. There adverse events could be dealt with oral over-the-counter medications, with no requirement of hospitalization.


Assuntos
Vacinas contra COVID-19 , COVID-19 , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , ChAdOx1 nCoV-19 , Estudos Transversais , Atenção à Saúde , Feminino , Humanos , Masculino
8.
Org Biomol Chem ; 20(22): 4599-4607, 2022 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-35603784

RESUMO

Alkaline phosphatase (ALP) is an important biomarker to diagnose a number of diseases, such as anaemia, hepatobiliary diseases, chronic nephritis, and hypothyroidism. Therefore, the development of simple and convenient assays to monitor levels of ALP is highly desirable. In the present study, an aggregation-induced emission based simple, real-time, and direct fluorescence detection platform has been developed, by using a tetracationic pyridinium derivative of tetraphenylethylene (TPy-TPE) and anionic sodium hexametaphosphate (HMP) as component units. The sensing system, based on the TPy-TPE-HMP assembly, is highly responsive to the ALP dependent disintegration of the TPy-TPE-HMP aggregation complex, owing to HMP digestion by ALP. The sensing platform has an ALP detection limit of 16 mU mL-1 and linear range of 0-742 mU mL-1, respectively. The enzyme kinetic parameters, Km and Vmax, have been evaluated. In addition, the potential applicability of the TPy-TPE-HMP sensing system has also been shown with diluted human serum samples. Moreover, the TPy-TPE-HMP probe system is also useful for screening inhibitors of ALP.


Assuntos
Fosfatase Alcalina , Corantes Fluorescentes , Cátions , Fluorometria , Humanos , Fosfatos
9.
J Phys Chem B ; 126(5): 1147-1155, 2022 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-35103477

RESUMO

The combination of supramolecular chemistry and aggregation-induced emission-based luminogens (AIEgens) has recently attracted tremendous attention because of its ability to offer large emission enhancement even in substantially dilute solutions. In this work, a new aggregation-induced emission (AIE)-based supramolecular assembly has been reported, which consists of a polyanionic cyclodextrin derivative and a tetracationic tetraphenylethylene (TPE) derivative. Ionic cyclodextrins have attracted significant attention in host-guest supramolecular chemistry and pharmaceutical industry. However, ionic derivatives of ß-cyclodextrins have not been explored to establish noncovalent interactions-based aggregation assembly of the most popular class of AIEgens, i.e., tetraphenylethylene derivatives. The current report demonstrates AIE of a tetracationic methyl pyridinium derivative of tetraphenylethylene (TPy-TPE) induced by a polyanionic sulfated ß-cyclodextrin (S-ßCD). The AIE-based supramolecular assembly has been thoroughly investigated using steady-state fluorescence, ground-state absorbance, and time-resolved fluorescence measurements. Further, the response of the supramolecular assembly towards external stimuli, such as, ionic strength, pH, and temperature, has been investigated. In addition, the complexation behavior of the TPE derivative has also been compared with the native neutral ß-cyclodextrin derivative, which delineates the important role of the negatively charged portal of S-ßCD in inducing aggregation of the TPy-TPE. The stoichiometry of the complex has been found to be 3:1 for TPy-TPE:S-ßCD, using Job's plot analysis. Finally, to get insights into the underlying interactions between the supramolecular assembly components, molecular docking calculations have been performed.


Assuntos
Ciclodextrinas , Estilbenos , Cátions , Simulação de Acoplamento Molecular , Estilbenos/química
10.
Crit Rev Anal Chem ; 52(5): 949-967, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33252991

RESUMO

Trypsin, a pancreatic serine protease, due to its narrow specificity and selectivity, has been tremendously used in food technology, proteome analysis, modulating soy protein allergenicity, antihypertensive peptide production, as well as, a biomarker in diseases such as pancreatitis, cystic fibrosis etc. Therefore, simple, sensitive and selective biosensors, for trypsin evaluation, are strongly recommended. This review provides, for the first time, an overview of various sensing systems, developed for the detection of trypsin. We have categorized various sensors, developed in the last ten years, according to their signal output as optical (fluorescence, colorimeter, surface plasmon resonance, liquid crystals), electrochemical (photo-electrochemical, nanopore sensors), piezoelectric and enzyme linked immunosorbant assay based sensors. Under each section, further subsections explain, construction of biosensors on the basis of various natural proteins acting as substrate unit and nucleic acids, nanoparticles, inorganic dyes, polymers etc. as participant interacting units. Their working principles and strategies along with salient features, such as, limit of detection, linearity range, time etc. have been critically analyzed to highlight their comparative merits and demerits. The most sensitive biosensors for trypsin detection is a photo-electrochemical anti-trypsin based immunosensor, with a lowest limit of detection 0.02 ng mL-1; linearity 0.10-100 ng mL-1.


Assuntos
Técnicas Biossensoriais , Nanopartículas , Tripsina , Imunoensaio , Ressonância de Plasmônio de Superfície , Tripsina/análise
11.
PLOS Glob Public Health ; 2(10): e0000437, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36962491

RESUMO

Transgender women globally are disproportionately burdened by HIV. Co-occurring epidemics of adverse psychosocial exposures accelerate HIV sexual risk, including among transgender women; however, studies using additive models fail to examine synergies among psychosocial conditions that define a syndemic. We examined the impact of synergistic interactions among 4 psychosocial exposures on condomless anal sex (CAS) among transgender women in India. A national probability-based sample of 4,607 HIV-negative transgender women completed the Indian Integrated Biological and Behavioural Surveillance survey, 2014-2015. We used linear probability regression and logistic regression to assess 2-, 3-, and 4-way interactions among 4 psychosocial exposures (physical violence, sexual violence, drug use, and alcohol use) on CAS. Overall, 27.3% reported physical and 22.3% sexual violence victimization (39.2% either physical or sexual violence), one-third (33.9%) reported frequent alcohol use and 11.5% illicit drug use. Physical violence was associated with twofold higher odds of CAS in the main effects model. Statistically significant two- and three-way interactions were identified, on both the multiplicative and the additive scales, between physical violence and drug use; physical and sexual violence; physical violence, sexual violence, and alcohol use; and physical violence, alcohol use and drug use. Physical and sexual violence victimization, and alcohol and drug use are highly prevalent and synergistically interact to increase CAS among HIV-negative transgender women in India. Targeted and integrated multilevel initiatives to improve the assessment of psychosocial comorbidities, to combat systemic transphobic violence, and to provide tailored, trauma-informed alcohol and substance use treatment services may reduce HIV risk among transgender women.

12.
J Indian Soc Pedod Prev Dent ; 39(1): 61-66, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33885389

RESUMO

BACKGROUND: Lead accumulations have been found in teeth and related to behavior deficits in children, but there is a dearth of studies in exploring the role of zinc and manganese dysregulations in autism spectrum disorders (ASD) using the primary tooth as biomarker. AIMS: The objectives of the study were to evaluate and compare the concentrations of zinc and manganese in the primary teeth serving as biomarker, in typically developing children and children with ASD. SETTINGS AND DESIGN: Twelve primary incisors indicated for extraction were collected from children between the age group 6 and 9 years, for the study. Six primary incisors were obtained from children who had been diagnosed with ASD (study group). The other six teeth were obtained from typically developing children, in the similar age group. METHODS: The primary incisors obtained were analyzed for metal concentrations using the technique Inductively Coupled Plasma Optical Emission Spectrometry. STATISTICAL ANALYSIS: This study was statistically analyzed by student's t-test. RESULTS: It was observed that there are significant differences in metal concentrations found between tooth samples of ASD children and typically developing children. Zinc concentrations were double and manganese concentrations were three times, in teeth of ASD children group as compared to the children in the control group. CONCLUSIONS: Results of the current study indicate that there are considerable differences in concentrations of zinc and manganese between the two groups and support the contention that there might be an association between metal exposures of a pregnant mother and child during early years of childhood and incidence of ASD.


Assuntos
Transtorno do Espectro Autista , Criança , Feminino , Humanos , Gravidez , Transtorno do Espectro Autista/diagnóstico , Biomarcadores , Manganês , Dente Decíduo
13.
Phys Chem Chem Phys ; 22(27): 15105-15119, 2020 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-32613964

RESUMO

Organophosphorus pesticides, widely used as insecticides for crop protection, are classified as an extremely toxic class of chemical compounds by the World Health Organization (WHO). Organophosphorus pesticides show marked specificity for the enzyme acetylcholinesterase, and can cause irreversible harm to the nervous system. The excessive use of organophosphorus pesticides, specifically in developing countries, made WHO to impose a ban on certain organophosphorus pesticides being sold to the developing nations. WHO and the Food and Agriculture Organization of United Nations, in joint meetings on pesticide residues, have stressed the need to develop easy, rapid, and sensitive methods to detect the presence of organophosphorus pesticides in food and water. In this regard, a number of review articles have been published explaining a myriad of detection methods for organophosphorus pesticides. Among these, optical detection methods, using biological molecules as the recognition element, provide a number of advantages, such as, high sensitivity and selectivity, simple operation, fast response and cheap instrumentation, and can really prove to be an effective alternative to the time-consuming traditional methods in the current scenario. Therefore, in this review article, we have discussed the recent advances in the field of biosensors employing the optical detection of organophosphorus pesticides. Specifically, various biosensors developed, using enzymes acetylcholinesterase and organophosphate hydrolase, have been categorized on the basis of the material used for their fabrication. A systematic discussion of the working principles, analytical parameters, and advantages and disadvantages of the various biosensors, has been attempted, along with a future perspective, on the challenges and possible improvements in the field of optical detection of organophosphorus pesticides.


Assuntos
Acetilcolinesterase/química , Técnicas Biossensoriais , Dispositivos Ópticos , Compostos Organofosforados/análise , Praguicidas/análise , Monoéster Fosfórico Hidrolases/química , Acetilcolinesterase/metabolismo , Animais , Humanos , Compostos Organofosforados/metabolismo , Praguicidas/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo
14.
J Caring Sci ; 9(1): 9-12, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32296653

RESUMO

Introduction: Childbirth is a distinctive and joyous moment in every mother's life. Giving birth is one of the powerful and vital event. This study aimed to assess and evaluate the effectiveness of warm compression (moist heat) on lumbo-sacral region in terms of labor pain intensity and labor outcomes Methods: An experimental research design was carried out on 88 nulliparous mothers with normal singleton term pregnancy (44 participants in each group) who were admitted in the labor room. Mothers who had high-risk pregnancy were excluded. Warm compression was given to nulliparous mothers of the experimental group with hydrochollator pack at 70◦C temperature for 20 minutes for 3 times with one-hour interval on lumbo sacral region starting from 4-5 cm of cervical dilatation. Labor pain intensity score, fetal heart rate, frequency and duration of uterine contractions were assessed before and immediately of warm compression and again after 30 minutes only labor pain was assessed. Results: Study results revealed that immediately after first, second and third time of warm compression labor pain intensity score in experimental group was lower than control group respectively ( t= 3.20; P< 0.001; t =4.45; P< 0.001; t= 6.18; P< 0.001). But no significant difference found in fetal heart rate and labor outcomes in terms of duration of labor, type of delivery, baby born alive/ not and cried immediately after birth. Conclusion: Warm compression was useful method to decrease the labour pain among nulliparous mothers in the first stage of labour and mothers reported satisfaction with intervention.

15.
PLoS One ; 15(1): e0225892, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31923189

RESUMO

BACKGROUND: Unhealthy dietary behaviour-high intake of fat, sugar, and salt, and low intake of fruits and vegetables-is a major risk factor for chronic diseases. There is a lack of evidence-based interventions to promote healthy dietary intake among Indian populations. Therefore, we tested the effectiveness of an information technology-enabled 'SMART Eating' intervention to reduce the intake of fat, sugar and salt, and to increase the intake of fruits and vegetables. METHODS: In Chandigarh, a North Indian city, a cluster randomized controlled trial was implemented in twelve geographical clusters, based on the type of housing (i.e., LIG: Low-income group; MIG; Middle-income group, and HIG: High-income group-a proxy for socio-economic status). Computer-generated randomization was used to allocate clusters to intervention and comparison arms after pairing on the basis of socioeconomic status and geographical distance between clusters. The sample size was 366 families per arm (N = 732). One adult per family was randomly selected as an index case to measure the change in the outcomes. For behaviour change, a multi-channel communication approach was used, which included information technology-short message service (SMS), email, social networking app and 'SMART Eating' website, and interpersonal communication along with distribution of a 'SMART Eating' kit-kitchen calendar, dining table mat, and measuring spoons. The intervention was implemented at the family level over a period of six months. The comparison group received pamphlets on nutrition education. Outcome measurements were made at 0 and 6 months post-intervention at the individual level. Primary outcomes were changes in mean dietary intakes of fat, sugar, salt, and fruit and vegetables. Secondary outcomes included changes in body mass index (BMI), blood pressure, haemoglobin, fasting plasma glucose (FPG), and serum lipids. Mixed-effects linear regression models were used to determine the net change in the outcomes in the intervention group relative to the comparison group. RESULTS: Participants' mean age was 53 years, a majority were women (76%), most were married (90%) and 51% had completed a college degree. All families had mobile phones, and more than 90% of these families had access to Internet through mobile phones. The intervention group had significant net mean changes of -12.5 g/day (p<0.001), -11.4 g/day (p<0.001), -0.5 g/day (p<0.001), and +71.6 g/day (p<0.001) in the intake of fat, sugar, salt, and fruit and vegetables, respectively. Similarly, significant net changes occurred for secondary outcomes: BMI -0.25 kg/m2, diastolic blood pressure -2.77 mm Hg, FPG -5.7 mg/dl, and triglycerides -24.2mg/dl. The intervention had no effect on haemoglobin, systolic blood pressure, low-density lipoprotein cholesterol, or high-density lipoprotein cholesterol. CONCLUSION: The IT-enabled 'SMART Eating' intervention was found to be effective in reducing fat, sugar, and salt intake, and increasing fruit and vegetable consumption among urban adults from diverse socio-economic backgrounds. TRIAL REGISTRATION: Clinical Trial Registry of India CTRI/2016/11/007457.


Assuntos
Comportamento Alimentar , Promoção da Saúde , Avaliação de Programas e Projetos de Saúde , Adulto , Idoso , Biomarcadores/análise , Glicemia/análise , Pressão Sanguínea , Índice de Massa Corporal , Feminino , Educação em Saúde , Hemoglobinas/análise , Humanos , Internet , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Classe Social , Rede Social , Envio de Mensagens de Texto
16.
Int J Mycobacteriol ; 8(4): 409-411, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31793516

RESUMO

After a steady decline throughout the 20th century, the incidence of tuberculosis (TB) in industrialized countries has started to rise again. However, in developing countries like India, the menace of TB had never been controlled. Gastrointestinal (GI) TB is rare, and the GI tract is considered only the sixth most frequent site of extrapulmonary TB. Esophageal TB (ET) is still rarer. This is a case report of a rare form of ET in a patient presenting with dysphagia. The patient was subjected to upper GI endoscopy, which revealed an ulcerative growth in the distal esophagus. Histopathology revealed ET. The patient was managed conservatively with anti-TB treatment (ATT). In spite of the rare nature of the disease, it can be managed effectively with ATT to avoid complications (fistula, stricture, and esophageal perforation), which might warrant surgery.


Assuntos
Esôfago/diagnóstico por imagem , Esôfago/microbiologia , Tuberculose Gastrointestinal/diagnóstico por imagem , Antituberculosos/uso terapêutico , Duodenoscopia , Humanos , Masculino , Pessoa de Meia-Idade , Mucosa/microbiologia , Mucosa/patologia , Escarro/microbiologia , Resultado do Tratamento , Tuberculose Gastrointestinal/tratamento farmacológico
17.
Photochem Photobiol ; 95(2): 543-555, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30240005

RESUMO

The photophysics of green fluorescent protein (GFP) is remarkable because of its exceptional property of excited state proton transfer (ESPT) and the presence of a functional proton wire. Another interesting property of wild-type GFP is that its absorption and fluorescence excitation spectra are sensitive to the presence of polar organic solvents even at very low concentrations. Here, we use a combination of methodologies including site-specific mutagenesis, absorption spectroscopy, steady-state and time-resolved fluorescence measurements and all-atom molecular dynamics simulations in explicit solvent, to uncover the mechanism behind the unique spectral sensitivity of GFP toward organic solvents. Based on the evidences provided herein, we suggest that organic solvent-induced changes in the proton wire prevent ground state movement of a proton through the wire and thus bring about the spectral changes observed. The present study can not only help to understand the mechanism of proton transfer by further dissecting the intricate steps in GFP photophysics but also encourages to develop GFP-based organic solvent biosensors.


Assuntos
Proteínas de Fluorescência Verde/química , Histidina/química , Compostos Orgânicos/química , Serina/química , Solventes/química , Treonina/química
18.
Glob Health Action ; 11(1): 1419738, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29370744

RESUMO

Nutrition is an important determinant of health. At present, nutrition programs in India mainly emphasize improving maternal and child nutrition. Adult nutrition has not received due attention, though diseases like hypertension and diabetes are largely preventable through changes in dietary and physical activity behaviour. Little is known about the best approaches to improve dietary behaviours, especially the role of modern information technology (IT) in health education. We describe the protocol of the SMART Eating (Small, Measurable and Achievable dietary changes by Reducing fat, sugar and salt consumption and Trying different fruits and vegetables) health promotion intervention. A Cluster Randomised Controlled Trial will evaluate the effect of an IT-enabled intervention on nutrition behaviour among urban adults of Chandigarh, India. Formative research using a qualitative exploratory approach was undertaken to inform the intervention. The IT-enabled intervention programme includes website development, Short Message Service (SMS), e-mail reminders and interactive help by mobile and landline phones. The IT-enabled intervention will be compared to the traditional nutrition education program of distributing pamphlets in the control group. The primary outcome will be the percentage of study participants meeting the dietary intake guidelines of the National Institute of Nutrition, Hyderabad, India and the change in intake of fat, sugar, salt, fruit and vegetables after the intervention. The difference in differences method will be used to determine the net change in dietary intakes resulting from the interventions. Measurements will be made at baseline and at 6 months post-intervention, using a food frequency questionnaire. The formative research led to the development of a comprehensive intervention, focusing on five dietary components and using multi-channel communication approach including the use of IT to target urban North Indians from diverse socio-economic backgrounds. The Cluster Randomised Controlled Trial design is suitable for evaluating the effectiveness of this IT-enabled intervention for dietary behaviour change.


Assuntos
Dieta Saudável , Promoção da Saúde/organização & administração , Tecnologia da Informação , Adulto , Correio Eletrônico , Feminino , Frutas , Educação em Saúde/organização & administração , Humanos , Índia , Internet , Masculino , Pessoa de Meia-Idade , Política Nutricional , Estado Nutricional , Envio de Mensagens de Texto , Verduras
19.
J Clin Diagn Res ; 9(9): ZC61-4, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26501015

RESUMO

BACKGROUND: The rapid progress of adhesive dentistry over the past decade has been attributed to the significant advances in dentin bonding technology. Requirements of an ideal bonding agent are quite similar to those indicated by Buonocore despite of many improvements. As we enter the new millennium, it is important for us to examine the past. OBJECTIVE: To evaluate the microleakage of three bonding agents namely Single Bond, Prime & Bond NT and Excite using different composite materials namely Z100, Spectrum TPH, Tetric with three different placement techniques. MATERIALS AND METHODS: Fifty four extracted human premolars were taken & divided into 9 groups depending upon application of bonding agents followed by composite restorations. Specimens were subjected to thermal cycling at 6(0)C, 37(0)C, 54(0)C and again at 37(0)C & then placed in 10 ml each of freshly prepared 50% silver nitrate solution for 2 hour in darkness, washed & placed under sun light for 24 hours. The sectioned specimens were then observed under stereomicroscope to detect microleakage. RESULTS: On comparing the mean microleakage scores among the three groups, maximum microleakage scores have been obtained when no bonding agent was used, while least microleakage scores were obtained with double coat of bonding agent. CONCLUSION: The present study suggests that the placement of bonding agent technique before composite restoration can be effective to limit the microleakage at the tooth restoration interface.

20.
J Clin Diagn Res ; 9(7): ZC72-5, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26417555

RESUMO

INTRODUCTION: Posterior transverse discrepancy as seen in some cases of Class II Division 1 malocclusion in mixed dentition period can be related to typical skeletofacial characteristics. These features when studied early in the mixed dentition period give a clear view of the desired appropriate treatment plan in a particular case. AIM: The purpose of this study was to establish a simple method to determine the posterior (intermolar) transverse discrepancy and craniofacial skeletal features between the dental arches during the mixed dentition in a sample of Class II Division 1 patients to provide diagnostic and therapeutic guidance in the early approach. MATERIALS AND METHODS: A sample of 60 Class II Division 1 patients in mixed dention that were divided into 30 Class II Division 1 patients with posterior transverse interarch discrepancy {Class II (I) PTID group} and 30 Class II Division 1 patients without posterior transverse interarch discrepancy {Class II (I) NPTID group}. Thirty Class I subjects in mixed dentition were included as control. RESULTS: The skeletal features of the Class II group without PTID are those of the skeletal Class II associated with 'anatomic' mandibular retrusion (due to a micrognathic mandible) and those of the Class II group with PTID as skeletal Class II associated with only a 'functional' mandibular retrusion (due to a posteriorly displaced mandible of normal size). CONCLUSION: This study confirmed the role of occlusion in the control of maxillomandibular skeletal relationships.The treatment strategies could be planned on the basis of the transverse component of Class II Division 1 groups in the mixed dentition period.

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