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1.
Environ Res ; 212(Pt B): 113295, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35452668

RESUMO

Metal nanoparticles furnished by the green synthesis approach have exhibited fascinating attributes owing to their biocompatibility with biomolecules, and their rapid environmentally friendly synthesis. On copper oxide (CuO) nanoparticles, a laser induced bio reduction work has been accomplish using Centella asiatica aqueous extract at room temperature is the pioneer in the field. This synthesis technique is easy, fruitful, eco-friendly, and counterfeit for the size-tunable synthesis of diverse shapes of stable copper nanoparticles. UV-visible spectroscopy, Field Emission Scanning Electron Microscopy (FESEM), Fourier Transform Infrared Spectroscopy (FTIR), Energy - Dispersive X-ray Spectroscopy (EDX), X-ray diffraction (XRD) and photodegradation study have astounding properties of regulating the formation, crystalline nature, and morphology of an integrated specimen. Moreover, the obtained copper oxide nanoparticle has the tendency to decrease the absorbance maximum value of methylene blue because of the catalytic activity posed by these nanoparticles on the reduction of methylene blue by Centella asiatica. It has been studied and confirmed by UV-visible spectrophotometer, and it has been recognised as an electron relay effect.


Assuntos
Cobre , Nanopartículas Metálicas , Cobre/química , Lasers , Nanopartículas Metálicas/química , Azul de Metileno/química , Extratos Vegetais/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
2.
Lancet Oncol ; 22(11): 1518-1529, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34634254

RESUMO

BACKGROUND: A randomised trial designed to compare three and two doses of quadrivalent human papillomavirus (HPV) vaccine in adolescent girls in India was converted to a cohort study after suspension of HPV vaccination in trials by the Indian Government. In this Article, the revised aim of the cohort study was to compare vaccine efficacy of single dose to that of three and two doses in protecting against persistent HPV 16 and 18 infection at 10 years post vaccination. METHODS: In the randomised trial, unmarried girls aged 10-18 years were recruited from nine centres across India and randomly assigned to either two doses or three doses of the quadrivalent HPV vaccine (Gardasil [Merck Sharp & Dohme, Whitehouse Station, NJ, USA]; 0·5 mL administered intramuscularly). After suspension of recruitment and vaccination, the study became a longitudinal, prospective cohort study by default, and participants were allocated to four cohorts on the basis of the number vaccine doses received per protocol: the two-dose cohort (received vaccine on days 1 and 180 or later), three-dose cohort (days 1, 60, and 180 or later), two-dose default cohort (days 1 and 60 or later), and the single-dose default cohort. Participants were followed up yearly. Cervical specimens were collected from participants 18 months after marriage or 6 months after first childbirth, whichever was earlier, to assess incident and persistent HPV infections. Married participants were screened for cervical cancer as they reached 25 years of age. Unvaccinated women age-matched to the married vaccinated participants were recruited to serve as controls. Vaccine efficacy against persistent HPV 16 and 18 infections (the primary endpoint) was analysed for single-dose recipients and compared with that in two-dose and three-dose recipients after adjusting for imbalance in the distribution of potential confounders between the unvaccinated and vaccinated cohorts. This trial is registered with ISRCTN, ISRCTN98283094, and ClinicalTrials.gov, NCT00923702. FINDINGS: Vaccinated participants were recruited between Sept 1, 2009, and April 8, 2010 (date of vaccination suspension), and followed up over a median duration of 9·0 years (IQR 8·2-9·6). 4348 participants had three doses, 4980 had two doses (0 and 6 months), and 4949 had a single dose. Vaccine efficacy against persistent HPV 16 and 18 infection among participants evaluable for the endpoint was 95·4% (95% CI 85·0-99·9) in the single-dose default cohort (2135 women assessed), 93·1% (77·3-99·8) in the two-dose cohort (1452 women assessed), and 93·3% (77·5-99·7) in three-dose recipients (1460 women assessed). INTERPRETATION: A single dose of HPV vaccine provides similar protection against persistent infection from HPV 16 and 18, the genotypes responsible for nearly 70% of cervical cancers, to that provided by two or three doses. FUNDING: Bill & Melinda Gates Foundation.


Assuntos
Vacina Quadrivalente Recombinante contra HPV tipos 6, 11, 16, 18/imunologia , Papillomavirus Humano 16/imunologia , Papillomavirus Humano 18/imunologia , Infecções por Papillomavirus/prevenção & controle , Vacinação/métodos , Adolescente , Colo do Útero/patologia , Colo do Útero/virologia , Criança , Feminino , Vacina Quadrivalente Recombinante contra HPV tipos 6, 11, 16, 18/administração & dosagem , Papillomavirus Humano 16/isolamento & purificação , Papillomavirus Humano 18/isolamento & purificação , Humanos , Índia , Estudos Longitudinais , Infecções por Papillomavirus/diagnóstico , Estudos Prospectivos , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/prevenção & controle
3.
Lancet Oncol ; 17(1): 67-77, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26652797

RESUMO

BACKGROUND: An increase in worldwide HPV vaccination could be facilitated if fewer than three doses of vaccine are as effective as three doses. We originally aimed to compare the immunogenicity and frequency of persistent infection and cervical precancerous lesions caused by vaccine-targeted HPV after vaccination with two doses of quadrivalent vaccine on days 1 and 180 or later, with three doses on days 1, 60, and 180 or later, in a cluster-randomised trial. Suspension of the recruitment and vaccination due to events unrelated to our study meant that some enrolled girls could not be vaccinated and some vaccinated girls received fewer than the planned number of vaccinations by default. As a result, we re-analysed our data as an observational cohort study. METHODS: Our study was designed to be done in nine locations (188 clusters) in India. Participants were unmarried girls aged 10-18 years vaccinated in four cohorts: girls who received three doses of vaccine on days 1, 60, and 180 or later, two doses on days 1 and 180 or later, two doses on days 1 and 60 by default, and one dose by default. The primary outcomes were immunogenicity in terms of L1 genotype-specific binding antibody titres, neutralising antibody titres, and antibody avidity after vaccination for the vaccine-targeted HPV types 16, 18, 6, and 11 and incident and persistent infections with these HPVs. Analysis was per actual number of vaccine doses received. This study is registered with ISRCTN, number ISRCTN98283094; and with ClinicalTrials.gov, number NCT00923702. FINDINGS: Vaccination of eligible girls was initiated on Sept 1, 2009, and continued until April 8, 2010. Of 21 258 eligible girls identified at 188 clusters, 17 729 girls were recruited from 178 clusters before suspension. 4348 (25%) girls received three doses, 4979 (28%) received two doses on days 1 and 180 or later, 3452 (19%) received two doses at days 1 and 60, and 4950 (28%) received one dose. Immune response in the two-dose HPV vaccine group was non-inferior to the three-dose group (median fluorescence intensity ratio for HPV 16 1·12 [95% CI 1·02-1·23] and for HPV 18 1·04 [0·92-1·19]) at 7 months, but was inferior in the two-dose default (0·33 [0·29-0·38] for HPV 16 and 0·51 [0·43-0·59] for HPV 18) and one-dose default (0·09 [0·08-0·11] for HPV 16 and 0·12 [0·10-0·14] for HPV 18) groups at 18 months. The geometric mean avidity indices after fewer than three doses by design or default were non-inferior to those after three doses of vaccine. Fewer than three doses by design and default induced detectable concentrations of neutralising antibodies to all four vaccine-targeted HPV types, but at much lower concentration after one dose. Cervical samples from 2649 participants were tested and the frequency of incident HPV 16, 18, 6, and 11 infections was similar irrespective of the number of vaccine doses received. The testing of at least two samples from 838 participants showed that there was no persistent HPV 16 or 18 infections in any study group at a median follow-up of 4·7 years (IQR 4·2-5·1). INTERPRETATION: Despite the limitations imposed by the suspension of the HPV vaccination, our findings lend support to the WHO recommendation of two doses, at least 6 months apart, for routine vaccination of young girls. The short-term protection afforded by one dose of HPV vaccine against persistent infection with HPV 16, 18, 6, and 11 is similar to that afforded by two or three doses of vaccine and merits further assessment. FUNDING: Bill & Melinda Gates Foundation.


Assuntos
Anticorpos Antivirais/sangue , Vacina Quadrivalente Recombinante contra HPV tipos 6, 11, 16, 18/administração & dosagem , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/imunologia , Potência de Vacina , Adolescente , Anticorpos Neutralizantes/sangue , Colo do Útero/virologia , Criança , Relação Dose-Resposta a Droga , Esquema de Medicação , Término Precoce de Ensaios Clínicos , Feminino , Papillomavirus Humano 11/imunologia , Papillomavirus Humano 16/imunologia , Papillomavirus Humano 18/imunologia , Humanos , Incidência , Índia/epidemiologia , Infecções por Papillomavirus/prevenção & controle , Estudos Prospectivos , Vacinação/métodos
4.
Hum Vaccin Immunother ; 19(3): 2289242, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38078840

RESUMO

Long-term follow-up of a cohort of unmarried girls who received one, two, or three doses of quadrivalent HPV vaccine, between 10 and 18 years of age, in an Indian multi-centric study allowed us to compare antibody responses between the younger and older age cohorts at 10-years post-vaccination, and study the impact of initiation of sexual activity and cervical HPV infections on antibody levels. Among the younger (10-14 years) recipients of a single dose, 97.7% and 98.2% had detectable binding antibody titers against HPV 16 and HPV 18 respectively at ten years post-vaccination. The proportions among those receiving a single dose at age 15-18 years were 92.3% and 94.2% against HPV 16 and HPV 18 respectively. Mean HPV 16 binding antibody titers were 2.1 folds (95%CI 1.4 to 3.3) higher in those vaccinated at ages 10-14 years, and 1.9 folds (95%CI 1.2 to 3.0) higher in those vaccinated at 15-18 years compared to mean titers seen in the unvaccinated women. Compared to previous timepoints of 36 or 48 months, binding antibodies against HPV 16 and neutralizing antibodies against both HPV 16 and HPV 18 were significantly higher at 10 years. This rise was more pronounced in participants vaccinated at 15-18 years. No association of marital status or cervical HPV infections was observed with the rise in titer. Durability of antibody response in single dose recipients correlated well with the high efficacy of a single dose against persistent HPV 16/18 infections irrespective of age at vaccination, as we reported earlier.


Assuntos
Infecções por Papillomavirus , Vacinas contra Papillomavirus , Adolescente , Criança , Feminino , Humanos , Anticorpos Neutralizantes , Anticorpos Antivirais , Papillomavirus Humano 16 , Papillomavirus Humano 18 , Vacina Quadrivalente Recombinante contra HPV tipos 6, 11, 16, 18 , Infecções por Papillomavirus/prevenção & controle , Vacinação , Vacinas Combinadas
5.
PLoS One ; 15(12): e0244242, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33373380

RESUMO

In context of the ongoing multi-centric HPV vaccine study in India, unvaccinated married women (N = 1484) aged 18-23 years were recruited in 2012-2015 as age-matched controls to the vaccinated women and followed up yearly. We assess type-specific prevalence, natural history and potential determinants of human papillomavirus (HPV) infection in these unvaccinated women. Cervical samples were collected yearly for at least four consecutive years. A Multiplex Type-Specific E7-Based polymerase chain reaction assay was used to detect 21 HPV types. HPV prevalence was 36.4% during 6 years. Most common HPV types were 16 (6.5%) and 31 (6.1%). Highest persistence were observed for HPV 35 (62.5%) and 52 (25%). New HPV acquisition rate was 5.6/1000 person-months of observation (PMO), highest for HPV 16 (1.1/1000 PMO). Type-specific clearance rates ranged between 2.9-5.5/100 PMO. HPV 16 and/or 18 infections were 41% (95% CI 4-63%) lower among women with 2-<3 years between marriage and first cervical sample collection compared to those with <2 years. HPV prevalence and acquisition rates in young Indian women were lower than their Western counterparts. HPV 16 infections being most common shows the importance and potential impact of HPV vaccination in India. Women with 2-3 years exposure had reduced risk possibly due to higher infections clearance.


Assuntos
Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/administração & dosagem , Comportamento Sexual , Vacinação/estatística & dados numéricos , Adolescente , Adulto , Feminino , Humanos , Índia/epidemiologia , Estudos Longitudinais , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/virologia , Prevalência , Adulto Jovem
6.
Papillomavirus Res ; 7: 75-81, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30711698

RESUMO

Earlier publication from the ongoing multi-centric study of the International Agency for Research on Cancer to evaluate less than three doses of the quadrivalent Human Papillomavirus (HPV) vaccine in India amongst unmarried girls demonstrated non-inferior total antibody titres, neutralizing antibody titres and antibody avidity in 2-dose recipients compared to 3-dose recipients at 15-18 years of age (Bhatla et al., 2018) [7]. The number of participants recruited at 15-18 years of age was 1515 and 1795 in the 3-dose and the 2-dose groups respectively. At a median follow-up of 7 years, incident HPV 16/18 infections were detected in 1.6% women receiving two doses and 0.8% women receiving three doses at 15-18 years. Frequency of incident infection was 7.0% in the age- and site-matched unvaccinated women (N = 1484). No persistent infection from HPV 16 was observed in the 2- or 3-dose recipients and one (0.2%) persistent HPV 18 infection was documented, each in the 3-dose and 2-dose cohorts. Among the unvaccinated women, the frequency of HPV 16/18 persistent infection was 1.7%. The protection offered by two doses of quadrivalent HPV vaccine against incident and persistent infections in recipients at 15-18 years is comparable to that seen in 3-dose recipients at 15-18 years.


Assuntos
Vacina Quadrivalente Recombinante contra HPV tipos 6, 11, 16, 18/administração & dosagem , Vacina Quadrivalente Recombinante contra HPV tipos 6, 11, 16, 18/imunologia , Papillomavirus Humano 16/isolamento & purificação , Papillomavirus Humano 18/isolamento & purificação , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/prevenção & controle , Adolescente , Criança , Feminino , Seguimentos , Humanos , Incidência , Índia , Adulto Jovem
7.
Papillomavirus Res ; 5: 163-171, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29578097

RESUMO

Extending two-dose recommendations of HPV vaccine to girls between 15 and 18 years will reduce program cost and improve compliance. Immunogenicity and vaccine targeted HPV infection outcomes were compared between 1795 girls aged 15-18 years receiving two (1-180 days) and 1515 girls of same age receiving three (1-60-180 days) doses. Immunogenicity outcomes in 15-18 year old two-dose recipients were also compared with the 10-14 year old three-dose (N = 2833) and two-dose (N = 3184) recipients. The 15-18 year old two-dose recipients had non-inferior L1-binding antibody titres at seven months against vaccine-targeted HPV types compared to three-dose recipients at 15-18 years and three-dose recipients at 10-14 years of age. Neutralizing antibody titres at 18 months in 15-18 year old two-dose recipients were non-inferior to same age three-dose recipients for all except HPV 18. The titres were inferior to those in the 10-14 year old three-dose recipients for all targeted types. Frequency of incident infections from vaccine-targeted HPV types in the 15-18 year old two-dose recipients was similar to the three dose recipients. None of the girls receiving two or three doses had persistent infection from vaccine-targeted types. These findings support that two doses of HPV vaccine can be extended to girls aged 15-18 years.


Assuntos
Vacina Quadrivalente Recombinante contra HPV tipos 6, 11, 16, 18/administração & dosagem , Esquemas de Imunização , Imunogenicidade da Vacina , Infecções por Papillomavirus/prevenção & controle , Vacinação/métodos , Adolescente , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Estudos de Coortes , Feminino , Humanos , Índia/epidemiologia , Infecções por Papillomavirus/epidemiologia , Vacinação/economia
8.
Braz J Microbiol ; 45(4): 1221-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25763025

RESUMO

Metal nanoparticle synthesis is an interesting area in nanotechnology due to their remarkable optical, magnetic, electrical, catalytic and biomedical properties, but there needs to develop clean, non-toxic and environmental friendly methods for the synthesis and assembly of nanoparticles. Biological agents in the form of microbes have emerged up as efficient candidates for nanoparticle synthesis due to their extreme versatility to synthesize diverse nanoparticles with varying size and shape. In the present study, an eco favorable method for the biosynthesis of silver nanoparticles using marine bacterial isolate has been attempted. Very interestingly, molecular identification proved it as a strain of Ochrobactrum anhtropi. In addition, the isolate was found to have the potential to form silver nanoparticles intracellularly at room temperature within 24 h. The biosynthesized silver nanoparticles were characterized by UV-Vis spectroscopy, transmission electron microscope (TEM) and scanning electron microscope (SEM). The UV-visible spectrum of the aqueous medium containing silver nanoparticles showed a peak at 450 nm corresponding to the plasmon absorbance of silver nanoparticles. The SEM and TEM micrographs revealed that the synthesized silver nanoparticles were spherical in shape with a size range from 38 nm - 85 nm. The silver nanoparticles synthesized by the isolate were also used to explore its antibacterial potential against pathogens like Salmonella Typhi, Salmonella Paratyphi, Vibrio cholerae and Staphylococcus aureus.


Assuntos
Antibacterianos/farmacologia , Nanopartículas/metabolismo , Ochrobactrum/metabolismo , Prata/farmacologia , Antibacterianos/metabolismo , Organismos Aquáticos/classificação , Organismos Aquáticos/genética , Organismos Aquáticos/isolamento & purificação , Organismos Aquáticos/metabolismo , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Bactérias Gram-Negativas/efeitos dos fármacos , Microscopia Eletrônica , Nanopartículas/química , Nanopartículas/ultraestrutura , Ochrobactrum/classificação , Ochrobactrum/genética , Ochrobactrum/isolamento & purificação , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Prata/metabolismo , Análise Espectral , Staphylococcus aureus/efeitos dos fármacos , Temperatura , Fatores de Tempo
9.
3 Biotech ; 4(2): 121-126, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28324441

RESUMO

Biological synthesis of silver nanoparticles using microorganisms has received profound interest because of their potential to synthesize nanoparticles of various size, shape and morphology. In the current study, synthesis of silver nanoparticles by a bacterial strain (CS 11) isolated from heavy metal contaminated soil is reported. Molecular identification of the isolate showed it as a strain of Bacillus sp. On treating the bacteria with 1 mM AgNO3, it was found to have the ability to form silver nanoparticles extracellularly at room temperature within 24 h. This was confirmed by the visual observation and UV-Vis absorption at 450 nm. Further characterization of nanoparticles by transmission electron microscopy confirmed the size of silver nanoparticles in 42-92 nm range. Therefore, the current study is a demonstration of an efficient synthesis of stable silver nanoparticle by a Bacillus strain.

10.
Genet Mol Biol ; 33(1): 141-5, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21637618

RESUMO

Plant phenolic compounds form a valuable resource of secondary metabolites having a broad spectrum of biological activities. Type III polyketide synthases play a key role in the formation of basic structural skeleton of the phenolic compounds. As a group of medicinal plants, PKSs with novel features are expected in the genome of Zingiberaceae. The genomic exploration of PKS in Alpinia calcarata conducted in this study identified the presence of an unusual intron at the region forming the second exon of typical PKSs, forming a gateway information of distribution of novel PKSs in Zingiberaceae.

11.
Braz. j. microbiol ; 45(4): 1221-1227, Oct.-Dec. 2014. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-741271

RESUMO

Metal nanoparticle synthesis is an interesting area in nanotechnology due to their remarkable optical, magnetic, electrical, catalytic and biomedical properties, but there needs to develop clean, non-toxic and environmental friendly methods for the synthesis and assembly of nanoparticles. Biological agents in the form of microbes have emerged up as efficient candidates for nanoparticle synthesis due to their extreme versatility to synthesize diverse nanoparticles with varying size and shape. In the present study, an eco favorable method for the biosynthesis of silver nanoparticles using marine bacterial isolate has been attempted. Very interestingly, molecular identification proved it as a strain of Ochrobactrum anhtropi. In addition, the isolate was found to have the potential to form silver nanoparticles intracellularly at room temperature within 24 h. The biosynthesized silver nanoparticles were characterized by UV-Vis spectroscopy, transmission electron microscope (TEM) and scanning electron microscope (SEM). The UV-visible spectrum of the aqueous medium containing silver nanoparticles showed a peak at 450 nm corresponding to the plasmon absorbance of silver nanoparticles. The SEM and TEM micrographs revealed that the synthesized silver nanoparticles were spherical in shape with a size range from 38 nm - 85 nm. The silver nanoparticles synthesized by the isolate were also used to explore its antibacterial potential against pathogens like Salmonella Typhi, Salmonella Paratyphi, Vibrio cholerae and Staphylococcus aureus.


Assuntos
Antibacterianos/farmacologia , Nanopartículas/metabolismo , Ochrobactrum/metabolismo , Prata/farmacologia , Antibacterianos/metabolismo , Organismos Aquáticos/classificação , Organismos Aquáticos/genética , Organismos Aquáticos/isolamento & purificação , Organismos Aquáticos/metabolismo , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Bactérias Gram-Negativas/efeitos dos fármacos , Microscopia Eletrônica , Nanopartículas/química , Nanopartículas/ultraestrutura , Ochrobactrum/classificação , Ochrobactrum/genética , Ochrobactrum/isolamento & purificação , Filogenia , /genética , Análise de Sequência de DNA , Análise Espectral , Prata/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Temperatura , Fatores de Tempo
12.
Genet. mol. biol ; 33(1): 141-145, 2010. ilus
Artigo em Inglês | LILACS | ID: lil-566151

RESUMO

Plant phenolic compounds form a valuable resource of secondary metabolites having a broad spectrum of biological activities. Type III polyketide synthases play a key role in the formation of basic structural skeleton of the phenolic compounds. As a group of medicinal plants, PKSs with novel features are expected in the genome of Zingiberaceae. The genomic exploration of PKS in Alpinia calcarata conducted in this study identified the presence of an unusual intron at the region forming the second exon of typical PKSs, forming a gateway information of distribution of novel PKSs in Zingiberaceae.

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