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1.
Public Health ; 215: 106-117, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36682079

RESUMO

OBJECTIVE: To assess the effectiveness of prenatal and postnatal home visits (HVs) and women group meetings (WGMs) by paramedical professionals to improve maternal and child health outcomes in low- and middle-income countries (LMICs). STUDY DESIGN: Systematic review and meta-analysis. METHODS: We conducted a systematic review of trials published till December 2020, as per registered protocol in The International Prospective Register of Systematic Reviews (PROSPERO) (CRD42018091968). Outcomes were neonatal mortality rate (NMR), maternal mortality ratio (MMR), the incidence of low birth weight, and still birth rate (SBR). The Cochrane Pregnancy and Childbirth Group's Trials Register, Cochrane Central Register of Controlled Trials, PubMed, and Excerpta Medica Database (EMBASE) were searched. Pooled results were estimated using random-effects meta-analysis in RevMan version 5.2. RESULTS: Twenty-five trials met the inclusion criteria. HVs were the key intervention in 12, WGMs in 11, and both interventions in 2 trials. The pooled estimates have shown that NMR was significantly reduced by HVs (OR 0.77, confidence interval [CI]: 0.67-0.90, P = 0.0007, I2 = 77%) and WGMs (OR 0.76, CI: 0.65-0.90, P = 0.001, I2 = 71%). SBR was significantly reduced by HVs (OR 0.77, CI: 0.70-0.85; P < 0.001, I2 = 0%). Subgroup analysis of studies in which more than 10% of pregnant women participated in the WGMs showed significant reduction in NMR (OR 0.67, CI 0.58-0.77, P = 0.00001, I2 = 31%) and MMR (OR 0.55, CI 0.36-0.84, P = 0.005, I2 = 27%). Two studies reported improvement in birth weight by HVs. CONCLUSIONS: HVs and WGMs (with >10% pregnant women) by paramedical professionals are effective strategies in reducing the NMR and MMR in LMICs. HVs were also effective in reducing SBR.


Assuntos
Países em Desenvolvimento , Mulheres , Recém-Nascido , Gravidez , Humanos , Feminino , Criança , Visita Domiciliar , Recém-Nascido de Baixo Peso , Vitaminas , Avaliação de Resultados em Cuidados de Saúde
2.
Dent Mater J ; 40(2): 312-321, 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33055433

RESUMO

The objective of this study was to develop electrospun polycaprolactone (PCL) membranes blended with hydroxyapatite (HA) and evaluate its potential in differentiating inflamed dental pulp stem/progenitor cells (IDPSCs) into odontoblasts. Electrospun nanofibrous membrane consisting of PCL blended with 10 wt% and 15 wt% of HA were fabricated and the characterization was done by Scanning electron microscopy (SEM), Fourier- transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and contact angle analysis. Cytocompatibility, cell adhesion and odontogenic differentiation ability of the membranes were assessed by MTT, Live/Dead, SEM/DAPI and qPCR studies. The mineral deposition ability of the membranes with IDPSCs was estimated by SEM-EDS. The SEM analysis revealed a nanofibrous texture with an average fiber diameter of 140 nm for PCL, 220 nm for PCL10%HA and 250 nm for PCL15%HA. Among the membranes tested, PCL10%HA favored positive cell attachments, upregulated expression of DSPP and ALP gene and higher Ca/P ratio compared to PCL and PCL15%HA.


Assuntos
Nanofibras , Diferenciação Celular , Proliferação de Células , Polpa Dentária , Durapatita , Poliésteres , Células-Tronco , Alicerces Teciduais
3.
Adv Exp Med Biol ; 1078: 29-47, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30357617

RESUMO

Tissue engineering aims to fabricate and functionalise constructs that mimic the native extracellular matrix (ECM) in the closest way possible to induce cell growth and differentiation in both in vitro and in vivo conditions. Development of scaffolds that can function as tissue substitutes or augment healing of tissues is an essential aspect of tissue regeneration. Although there are many techniques for achieving this biomimicry in 2D structures and 2D cell cultures, translation of successful tissue regeneration in true 3D microenvironments is still in its infancy. Electrospinning, a well known electrohydrodynamic process, is best suited for producing and functionalising, nanofibrous structures to mimic the ECM. A systematic control of the processing parameters coupled with novel process innovations, has recently resulted in novel 3D electrospun structures. This chapter gives a brief account of the various 3D electrospun structures that are being tried as tissue engineering scaffolds. Combining electrospinning with other 3D structure forming technologies, which have shown promising results, has also been discussed. Electrospinning has the potential to bridge the gap between what is known and what is yet to be known in fabricating 3D scaffolds for tissue regeneration.


Assuntos
Nanofibras , Regeneração , Engenharia Tecidual/tendências , Alicerces Teciduais , Diferenciação Celular , Matriz Extracelular , Humanos
4.
Nanoscale ; 10(8): 3753-3758, 2018 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-29411816

RESUMO

A crucial step in the development of lithium-oxygen (Li-O2) batteries is to design an oxygen cathode with high catalytic activity and stable porous structure. Achieving such design requires an integrated strategy in which porosity, conductivity, catalytic activity, and mechanical durability are all considered in a battery system. Here, we develop polypyrrole-coated carbon x-aerogels with macroscopic 3D architecture, and demonstrate their potential as oxygen cathodes for Li-O2 batteries. This material, a novel and mechanically strong composite aerogel with polymer-cross-linked structure, not only provides effective pores that allow to store the discharge products and open channels for better oxygen diffusion, but also forms a robust 3D catalytic network that promotes both oxygen reduction and evolution reactions with improved mechanical and electrochemical stability. This work highlights the synergy between the 3D porous, conductive carbon aerogel framework and the polypyrrole catalytic layer, which maintains stable catalytic activity without deactivation and provides a more effective gas-liquid-solid interface for rapid oxygen absorption and diffusion, thereby leading to significant improvements in the capacity, rate capability and cycle life of the cathode.

5.
J Mater Sci Mater Med ; 28(8): 119, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28685233

RESUMO

Critical size defects in the craniofacial region can be effectively treated using three dimensional (3D) composite structures mimicking natural extra cellular matrix (ECM) and incorporated with bioactive ceramics. In this study we have shown that the dynamic liquid bath collector can be used to form electrospun polycaprolactone (PCL)-hydroxyapatite (HA) composite structure as unique 3D scaffold. The structure was found to have three distinct sections (base, stem and head) based on the mechanism of its formation and morphology. The size of the head portion was around 15 mm and was found to vary with the process parameters. Scanning electron microscopy (SEM) analysis revealed that the base had random fibres while the fibres in stem and head sections were aligned but perpendicular to each other. X-ray diffraction (XRD) analysis also showed an increase in the crystallinity index of the fibres from base to head section. Cytotoxicity and cytocompatibility studies using human osteosarcoma (HOS) cells showed good cell adhesion and proliferation indicating the suitability of the 3D structure for craniofacial graft applications.


Assuntos
Anormalidades Craniofaciais/terapia , Durapatita/química , Osteossarcoma/terapia , Poliésteres/química , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Materiais Biocompatíveis/química , Osso e Ossos , Adesão Celular , Proliferação de Células , Sobrevivência Celular , Cerâmica/química , Humanos , Microscopia Eletrônica de Varredura , Osteoblastos/citologia , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
6.
J Nanosci Nanotechnol ; 17(4): 2320-328, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29640156

RESUMO

Electrospinning is recently used in tissue engineering due to their excellent ability to mimic the structure of extra cellular matrix (ECM), a prerequisite for creating an optimal microenvironment for cell growth. Electrospun nanofibrous composite scaffolds consisting of polycaprolactone (PCL)/Poly(1,4-butylene adipate-co-polycaprolactam) (PBAPCL) blend with hydroxyapatite (HA) have been fabricated to enhance the wettability and osseointegrative properties. Fourier transform-infrared spectroscopy (FT-IR) confirmed molecular interactions of the polymer blend along with the presence of HA. X-ray diffraction analysis (XRD) indicated semi-crystalline nature of the mat and also the presence of HA in the composite mat. The morphology of the fibres, were analyzed using scanning electron microscopy (SEM) and the diameter was found to be in the range of 400­600 nm. The composite fibers were of larger diameter compared to their polymer counterparts. Improved wettability of the electrospun composite mat has been observed by contact angle analysis. In vitro cell culture studies by Live/Dead assay and MTT using human osteosarcoma (HOS) cells indicated the cytocompatible nature of electrospun mat which was further confirmed by cell adhesion using SEM and Actin-phalloidin staining. Addition of PBAPCL and HA to PCL have a beneficial effect on cell growth and proliferation thereby making the composite, a prospective scaffold for bone tissue engineering applications.


Assuntos
Osso e Ossos/citologia , Nanocompostos/química , Poliésteres/química , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Osso e Ossos/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Durapatita/química , Técnicas Eletroquímicas , Humanos , Nanofibras/química , Poliésteres/farmacologia , Molhabilidade
7.
Nanoscale ; 7(7): 3181-8, 2015 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-25615929

RESUMO

It is well known that both the structural morphology and chemical doping are important factors that affect the properties of metal hydroxide materials in electrochemical energy storage devices. In this work, an effective method to tailor the morphology and chemical doping of metal hydroxides is developed. It is shown that the morphology and the degree of crystallinity of Ni(OH)2 can be changed by adding glucose in the ethanol-mediated solvothermal synthesis. Ni(OH)2 produced in this manner exhibited an increased specific capacitance, which is partially attributed to its increased surface area. Interestingly, the effect of morphology on cobalt doped-Ni(OH)2 is found to be more effective at low cobalt contents than at high cobalt contents in terms of improving the electrochemical performance. This result reveals the existence of competitive effects between chemical doping and morphology change. These findings will provide important insights to design effective materials for energy storage devices.

8.
Dev Comp Immunol ; 47(1): 25-35, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24998226

RESUMO

Toll-like receptor 22 (TLR22) is present in teleost but not in mammals. Among Indian farmed carps, Catla catla is relatively more resistant than Labeo rohita to Argulus siamensis lice infection. TLR22 is believed to be associated with innate immunity against ectoparasite infection. To investigate the TLR22 mediated immunity against argulosis, we have cloned and characterized TLR22 genes of L. rohita (rTLR22) and C. catla (cTLR22). The full-length cDNAs of rTLR22 and cTLR22 contained an open reading frame of 2838 and 2841 nucleotides, respectively; bearing the typical structural features. Phylogenetically rTLR22/cTLR22 was most closely related to Cyprinus carpio (common carp) counterpart, having highest sequence identity of 86.0%. The TIR domain remained highly conserved with 90% identity within freshwater fishes. The sequence information of cDNA and genomic DNA together revealed that the rTLR22/cTLR22 genes are encoded by uninterrupted exons. The co-habitation challenge study with A. siamensis infection confirmed that C. catla is comparatively more resistant than L. rohita. Further, comparative mRNA expression profile in immune relevant tissues also suggested about the participatory role of TLR22 during lice infection. However, TLR22 might not solely be involved in conferring relative resistance among carp species against argulosis.


Assuntos
Arguloida/fisiologia , Carpas/imunologia , Carpas/parasitologia , Ectoparasitoses/veterinária , Doenças dos Peixes/imunologia , Proteínas de Peixes/imunologia , Receptores Toll-Like/imunologia , Sequência de Aminoácidos , Animais , Aquicultura , Sequência de Bases , Carpas/classificação , Ectoparasitoses/imunologia , Dados de Sequência Molecular , Filogenia , Receptores Toll-Like/química , Receptores Toll-Like/genética
9.
Sci Rep ; 3: 3195, 2013 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-24217312

RESUMO

Developing electrocatalysts with both high selectivity and efficiency for the oxygen reduction reaction (ORR) is critical for several applications including fuel cells and metal-air batteries. In this work we developed high performance electrocatalysts based on unique winged carbon nanotubes. We found that the outer-walls of a special type of carbon nanotubes/nanofibers, when selectively oxidized, unzipped and exfoliated, form graphene wings strongly attached to the inner tubes. After doping with nitrogen, the winged nanotubes exhibited outstanding activity toward catalyzing the ORR through the four-electron pathway with excellent stability and methanol/carbon monoxide tolerance. While the doped graphene wings with high active site density bring remarkable catalytic activity, the inner tubes remain intact and conductive to facilitate electron transport during electrocatalysis.

10.
Nanoscale ; 5(3): 1067-73, 2013 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-23254316

RESUMO

Supercapacitors with both high energy and high power densities are critical for many practical applications. In this paper, we discuss the design and demonstrate the fabrication of flexible asymmetric supercapacitors based on nanocomposite electrodes of MnO(2), activated carbon, carbon nanotubes and graphene. The combined unique properties of each of these components enable highly flexible and mechanically strong films that can serve as electrodes directly without using any current collectors or binders. Using these flexible electrodes and a roll-up approach, asymmetric supercapacitors with 2 V working voltage were successfully fabricated. The fabricated device showed excellent rate capability, with 78% of the original capacitance retained when the scan rate was increased from 2 mV s(-1) to 500 mV s(-1). Owing to the unique composite structure, these supercapacitors were able to deliver high energy density (24 W h kg(-1)) under high power density (7.8 kW kg(-1)) conditions. These features could enable supercapacitor based energy storage systems to be very attractive for a variety of critical applications, such as the power sources in hybrid electric vehicles and the back-up powers for wind and solar energy, where both high energy density and high power density are required.


Assuntos
Capacitância Elétrica , Fontes de Energia Elétrica , Eletrólitos/química , Grafite/química , Nanotubos de Carbono/química , Água/química , Módulo de Elasticidade , Transferência de Energia , Desenho de Equipamento , Análise de Falha de Equipamento , Teste de Materiais , Nanotubos de Carbono/ultraestrutura , Propriedades de Superfície
11.
Nano Lett ; 12(8): 4206-11, 2012 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-22823066

RESUMO

Flexible and lightweight energy storage systems have received tremendous interest recently due to their potential applications in wearable electronics, roll-up displays, and other devices. To manufacture such systems, flexible electrodes with desired mechanical and electrochemical properties are critical. Herein we present a novel method to fabricate conductive, highly flexible, and robust film supercapacitor electrodes based on graphene/MnO(2)/CNTs nanocomposites. The synergistic effects from graphene, CNTs, and MnO(2) deliver outstanding mechanical properties (tensile strength of 48 MPa) and superior electrochemical activity that were not achieved by any of these components alone. These flexible electrodes allow highly active material loading (71 wt % MnO(2)), areal density (8.80 mg/cm(2)), and high specific capacitance (372 F/g) with excellent rate capability for supercapacitors without the need of current collectors and binders. The film can also be wound around 0.5 mm diameter rods for fabricating full cells with high performance, showing significant potential in flexible energy storage devices.

12.
Sex Transm Infect ; 84(6): 434-8, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19028942

RESUMO

OBJECTIVES: To assess correlates of paid sex among men who have sex with men (MSM) in Chennai, India. METHODS: A randomised survey was conducted among 200 MSM recruited from public sex environments using time-space sampling. The association of predictors with paid sex was assessed with chi(2) tests and multiple logistic regression. RESULTS: Participants' mean age was 28.5 years (SD 8.7). Most (71.5%) were kothis; 60% had less than high school education and two-thirds had a monthly income less than 2000 Indian rupees. More than one-third (35.0%) reported daily/weekly harassment; 40.5% reported forced sex in the past year. The prevalence of paid sex was 59.5% (95% CI 52.7% to 66.3%). Univariate analyses indicated that paid sex was associated with kothi identity (chi(2) = 14.46; p<0.01), less than high school education (chi(2) = 4.79; p<0.05), harassment (chi(2) = 11.75; p<0.01) and forced sex (chi(2) = 3.98; p<0.05). Adjusted analyses revealed that paid sex was associated with kothi identity (adjusted odds ratio (AOR) 2.62, 95% CI 1.34 to 5.10) and harassment (AOR 2.34, 95% CI 1.16 to 4.72). MSM who engaged in paid sex (versus no paid sex) had a mean of 31 partners in the past month (versus 4, t = 6.17, p<0.001) and 71.2% used condoms consistently (versus 46.4%, chi(2) = 18.34; p<0.01). Overall, 32.5% were never tested for HIV. CONCLUSIONS: Epidemic rates of harassment and sexual violence against MSM who engage in paid sex, predominantly kothis, suggest that interventions should target structural factors placing these men at increased risk of HIV/sexually transmitted infections and other health-compromising conditions. The effectiveness of individual-level, knowledge-based and condom-focused preventive interventions may be constrained in the context of poverty, low education, harassment and sexual violence.


Assuntos
Homossexualidade Masculina/estatística & dados numéricos , Trabalho Sexual/estatística & dados numéricos , Adulto , Preservativos/estatística & dados numéricos , Métodos Epidemiológicos , Infecções por HIV/prevenção & controle , Conhecimentos, Atitudes e Prática em Saúde , Homossexualidade Masculina/etnologia , Humanos , Índia/epidemiologia , Índia/etnologia , Masculino , Trabalho Sexual/etnologia , Sexo sem Proteção/etnologia , Sexo sem Proteção/estatística & dados numéricos , Violência/etnologia , Violência/estatística & dados numéricos
13.
J LGBT Health Res ; 4(2-3): 81-7, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19856741

RESUMO

We conducted structured interviews with 200 men who have sex with men (MSM) recruited using time-space sampling from public sex environments (PSEs) in Chennai, India. Predictors of sexual risk behavior were assessed with chi2 tests and multiple logistic regression. One-third reported unprotected receptive anal sex (URAS) last time and 36% inconsistent condom use in the past month. URAS was associated with younger age, less than high school education, low income, and low HIV transmission knowledge (adjusted odds ratio [AOR] = 2.1, 2.5, 3.7 and 2.5, respectively). Inconsistent condom use was associated with less than high school education (AOR = 3.2) and low HIV transmission knowledge (AOR = 3.5). Multilevel HIV prevention strategies tailored for low socioeconomic kothis and other MSM in PSEs in Chennai should include peer interventions to increase knowledge of HIV transmission risks and sexually transmitted infections (STIs), and structural interventions to expand economic and educational opportunities, and accessible STI testing and treatment.


Assuntos
Homossexualidade Masculina/estatística & dados numéricos , Assunção de Riscos , Trabalho Sexual/estatística & dados numéricos , Transexualidade/epidemiologia , Adulto , Preservativos/estatística & dados numéricos , Escolaridade , Infecções por HIV/prevenção & controle , Infecções por HIV/transmissão , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Índia/epidemiologia , Entrevistas como Assunto , Masculino , Fatores de Risco , Sexo Seguro/estatística & dados numéricos , Fatores Socioeconômicos , Sexo sem Proteção/estatística & dados numéricos , Adulto Jovem
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