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1.
J Am Ceram Soc ; 103(11)2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37533536

RESUMO

The effect of a high-performance retarding additive in oil well cements was investigated under elevated temperature (165°C) and pressure (1000 psi) conditions via in situ synchrotron-based X-ray diffraction (XRD) and quasielastic neutron scattering (QENS) techniques. Under these temperature and pressure conditions, crystalline calcium silicate hydrates (C-S-H) are formed through the cement hydration process. From in situ XRD experiments, the retardation effect was observed by a change in the rate of the appearance of 11 Å tobermorites as well as a change in the rate of the α-C2SH generation and depletion. QENS analysis revealed that the retardation effect was related to the non-conversion of free water to chemical and constrained water components. A high presence of free water components was attributed to a decrease in 11 Å tobermorites along with slower consumption of the quartz and portlandite phases. Furthermore, QENS results infer that the water molecules experienced confinement in the restricted pore spaces. The retarder inhibited this initial water confinement by slowing the bulk diffusion of free water in the confined region.

2.
BMC Infect Dis ; 17(1): 293, 2017 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-28427352

RESUMO

BACKGROUND: Zika, dengue, and chikungunya are three mosquito-borne viruses having overlapping transmission vectors. They cause diseases having similar symptoms in human patients, but requiring different immediate management steps. Therefore, rapid (< one hour) discrimination of these three viruses in patient samples and trapped mosquitoes is needed. The need for speed precludes any assay that requires complex up-front sample preparation, such as extraction of nucleic acids from the sample. Also precluded in robust point-of-sampling assays is downstream release of the amplicon mixture, as this risks contamination of future samples that will give false positives. METHODS: Procedures are reported that directly test urine and plasma (for patient diagnostics) or crushed mosquito carcasses (for environmental surveillance). Carcasses are captured on paper samples carrying quaternary ammonium groups (Q-paper), which may be directly introduced into the assay. To avoid the time and instrumentation requirements of PCR, the procedure uses loop-mediated isothermal amplification (LAMP). Downstream detection is done in sealed tubes, with dTTP-dUTP mixtures in the LAMP with a thermolabile uracil DNA glycosylase (UDG); this offers a second mechanism to prevent forward contamination. Reverse transcription LAMP (RT-LAMP) reagents are distributed dry without requiring a continuous chain of refrigeration. RESULTS: The tests detect viral RNA in unprocessed urine and other biological samples, distinguishing Zika, chikungunya, and dengue in urine and in mosquitoes infected with live Zika and chikungunya viruses. The limits of detection (LODs) are ~0.71 pfu equivalent viral RNAs for Zika, ~1.22 pfu equivalent viral RNAs for dengue, and ~38 copies of chikungunya viral RNA. A handheld, battery-powered device with an orange filter was constructed to visualize the output. Preliminary data showed that this architecture, working with pre-prepared tubes holding lyophilized reagent/enzyme mixtures and shipped without a chain of refrigeration, also worked with human plasma samples to detect chikungunya and dengue in Pune, India. CONCLUSIONS: A kit, complete with a visualization device, is now available for point-of-sampling detection of Zika, chikungunya, and dengue. The assay output is read in ca. 30 min by visualizing (human eye) three-color coded fluorescence signals. Assay in dried format allows it to be run in low-resource environments.


Assuntos
Febre de Chikungunya/diagnóstico , Dengue/diagnóstico , Técnicas de Amplificação de Ácido Nucleico/métodos , Infecção por Zika virus/diagnóstico , Animais , Vírus Chikungunya/genética , Culicidae , Dengue/sangue , Dengue/urina , Vírus da Dengue/genética , Vírus da Dengue/patogenicidade , Feminino , Humanos , Índia , Limite de Detecção , Técnicas de Amplificação de Ácido Nucleico/instrumentação , RNA Viral/análise , RNA Viral/genética , RNA Viral/urina , Kit de Reagentes para Diagnóstico , Transcrição Reversa , Zika virus/genética , Zika virus/isolamento & purificação , Zika virus/patogenicidade
3.
Curr Drug Discov Technol ; 19(3): e040322201773, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35249493

RESUMO

The tropical parasitic infections account for more than 2 billion infections and cause substantial morbidity and mortality, and account for several million deaths every year. Majorly parasitic infections in humans and animals are caused by protozoa and helminths. Chronic infections in the host can cause retardation, impairment of cognitive skills, development in young children and weaken the immune system. The burden is felt to a greater extent in developing countries due to poverty, inaccessibility to medicines and resistance observed to drugs. Thus, human health continues to be severely harmed by parasitic infections. Medicinal plants have received much attention as alternative sources of drugs. Zanthoxylum genus has been used ethnobotanically as an antiparasitic agent and the phytoconstituents in Zanthoxylum, show a wide variety of chemical substances with proven pharmacological actions such as alkaloids (isoquinolines and quinolines responsible for antitumor activity, antimalarial, antioxidant and antimicrobial actions), lignans, coumarins (antibacterial, antitumour, vasodilatory and anticoagulant activities), alkamide (strong insecticidal properties, anthelminthic, antitussive and analgesic anti antimalarial property). Therefore, this article is an attempt to review the existing literature that emphasizes on potential of genus Zanthoxylum as a source of lead compounds for the treatment of parasitic diseases.


Assuntos
Alcaloides , Antimaláricos , Doenças Parasitárias , Plantas Medicinais , Zanthoxylum , Alcaloides/química , Animais , Doenças Parasitárias/tratamento farmacológico , Zanthoxylum/química
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 265: 120378, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34543989

RESUMO

The structure of water, especially around the solute is thought to play an important role in many biological and chemical processes. Water-peptide and cosolvent-peptide interactions are crucial in determining the structure and function of protein molecules. In this work, we present the H-bonding analysis for model peptides like glycyl-glycine (gly-gly), glycine-ւ-valine (gly-val), glycyl-ւ-leucine (gly-leu) and triglycine (trigly) and triethylammonium based carboxylate protic ionic liquids (PILs) in aqueous solutions as well as for peptides in ∼0.2 mol·L-1 of aqueous PIL solutions in the spectral range of 7800-5500 cm-1 using Fourier transform near-infrared (FT-NIR) spectroscopy at 298.15 K. The hydration numbers for peptides and PILs were obtained using NIR method of simultaneous estimation of hydration spectrum and hydration number of a solute dissolved in water. The H-bond of water molecules around peptides and PILs are found to be stronger and shorter than those in pure liquid water. We observe that the hydration shell around zwitterions is a clathrate-like cluster of water in which ions entrap. Watery network analysis confirms that singly H-bonded species or NHBs changes to partial or distorted ice-like structures of water in the hydration shell of PILs. The overall water H-bonding in the hydration sphere of PILs increases in the order TEAF < TEAA < TEAG < TEAPy ≈ TEAP < TEAB. The influence of PILs on hydration behavior of peptides is explored in terms of H-bonding, cooperativity, hydrophobicity, water structural changes, ionic interactions etc.


Assuntos
Líquidos Iônicos , Glicina , Peptídeos , Soluções , Água
5.
Indian J Gastroenterol ; 41(1): 37-51, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34989986

RESUMO

BACKGROUND: Dysbiotic gut bacteria engage in the development and progression of severe alcoholic hepatitis (SAH). We aimed to characterize bacterial communities associated with clinical events (CE), identify significant bacteria linked to CE, and define bacterial relationships associated with specific CE and outcomes at baseline and after treatment in SAH. METHODS: We performed 16-s rRNA sequencing on stool samples (n=38) collected at admission and the last follow-up within 90 days in SAH patients (n=26; 12 corticosteroids; 14 granulocyte colony-stimulating factor, [G-CSF]). Validated pipelines were used to plot bacterial communities, profile functional metabolism, and identify significant taxa and functional metabolites. Conet/NetworkX® was utilized to identify significant non-random patterns of bacterial co-presence and mutual exclusion for clinical events. RESULTS: All the patients were males with median discriminant function (DF) 64, Child-Turcotte-Pugh (CTP) 12, and model for end-stage liver disease (MELD) score 25.5. At admission, 27%, 42%, and 58% had acute kidney injury (AKI), hepatic encephalopathy (HE), and infections respectively; 38.5% died at end of follow-up. Specific bacterial families were associated with HE, sepsis, disease severity, and death. Lachnobacterium and Catenibacterium were associated with HE, and Pediococcus with death after steroid treatment. Change from Enterococcus (promotes AH) to Barnesiella (inhibits E. faecium) was significant after G-CSF. Phenylpropanoid-biosynthesis (innate-immunity) and glycerophospholipid-metabolism (cellular-integrity) pathways in those without infections and the death, respectively, were upregulated. Mutual interactions between Enterococcus cecorum, Acinetobacter schindleri, and Mitsuokella correlated with admission AKI. CONCLUSIONS: Specific gut microbiota, their interactions, and metabolites are associated with complications of SAH and treatment outcomes. Microbiota-based precision medicine as adjuvant treatment may be a new therapeutic area.


Assuntos
Injúria Renal Aguda , Doença Hepática Terminal , Microbioma Gastrointestinal , Hepatite Alcoólica , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Hepatite Alcoólica/microbiologia , Humanos , Masculino , Índice de Gravidade de Doença
6.
PLoS One ; 16(2): e0240524, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33626039

RESUMO

Managing the pandemic caused by SARS-CoV-2 requires new capabilities in testing, including the possibility of identifying, in minutes, infected individuals as they enter spaces where they must congregate in a functioning society, including workspaces, schools, points of entry, and commercial business establishments. Here, the only useful tests (a) require no sample transport, (b) require minimal sample manipulation, (c) can be performed by unlicensed individuals, (d) return results on the spot in much less than one hour, and (e) cost no more than a few dollars. The sensitivity need not be as high as normally required by the FDA for screening asymptomatic carriers (as few as 10 virions per sample), as these viral loads are almost certainly not high enough for an individual to present a risk for forward infection. This allows tests specifically useful for this pandemic to trade-off unneeded sensitivity for necessary speed, simplicity, and frugality. In some studies, it was shown that viral load that creates forward-infection risk may exceed 105 virions per milliliter, easily within the sensitivity of an RNA amplification architecture, but unattainable by antibody-based architectures that simply target viral antigens. Here, we describe such a test based on a displaceable probe loop amplification architecture.


Assuntos
Teste para COVID-19/métodos , COVID-19/virologia , Portador Sadio/virologia , SARS-CoV-2/isolamento & purificação , Adulto , Antígenos Virais/genética , COVID-19/diagnóstico , COVID-19/epidemiologia , COVID-19/genética , Portador Sadio/diagnóstico , Feminino , Humanos , Masculino , Técnicas de Amplificação de Ácido Nucleico/métodos , Pandemias , RNA Viral/genética , SARS-CoV-2/genética , Sensibilidade e Especificidade , Carga Viral
7.
Indian J Pediatr ; 87(2): 105-110, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31925720

RESUMO

OBJECTIVES: To screen for variants in the MC4R and LEP genes in 46 patients with clinical suspicion of non-syndromic early onset severe obesity (NEOSO). METHODS: Children with early onset obesity satisfying WHO criteria of obesity were studied. The MC4R and LEP genes were sequenced using a PCR amplicon based NGS on Illumina MiSeq next generation sequencer using an in-house developed protocol. RESULTS: Of the 46 children tested, four were found to have novel pathogenic/likely-pathogenic variants (one in the MC4R gene and three in the LEP gene). In three out of the 4 families, the presence of the variants was confirmed using standard bidirectional capillary sequencing in the probands. CONCLUSIONS: Four children with novel likely pathogenic variants in the MC4R and LEP genes are reported. Genetic analysis is crucial in children with early onset obesity and should be considered.


Assuntos
Predisposição Genética para Doença/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Leptina/genética , Obesidade Mórbida/diagnóstico , Obesidade Mórbida/genética , Receptor Tipo 4 de Melanocortina/genética , Pré-Escolar , Feminino , Testes Genéticos , Humanos , Lactente , Masculino
8.
Waste Manag ; 71: 426-439, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29033018

RESUMO

Concrete production contributes heavily to greenhouse gas emissions, thus a need exists for the development of durable and sustainable concrete with a lower carbon footprint. This can be achieved when cement is partially replaced with another material, such as waste plastic, though normally with a tradeoff in compressive strength. This study discusses progress toward a high/medium strength concrete with a dense, cementitious matrix that contains an irradiated plastic additive, recovering the compressive strength while displacing concrete with waste materials to reduce greenhouse gas generation. Compressive strength tests showed that the addition of high dose (100kGy) irradiated plastic in multiple concretes resulted in increased compressive strength as compared to samples containing regular, non-irradiated plastic. This suggests that irradiating plastic at a high dose is a viable potential solution for regaining some of the strength that is lost when plastic is added to cement paste. X-ray Diffraction (XRD), Backscattered Electron Microscopy (BSE), and X-ray microtomography explain the mechanisms for strength retention when using irradiated plastic as a filler for cement paste. By partially replacing Portland cement with a recycled waste plastic, this design may have a potential to contribute to reduced carbon emissions when scaled to the level of mass concrete production.


Assuntos
Pegada de Carbono , Plásticos , Reciclagem , Força Compressiva , Materiais de Construção
9.
Genome Announc ; 1(5)2013 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-24051317

RESUMO

The pandemic influenza A(H1N1)pdm09 virus was first detected in India in May 2009 and continued to circulate in the postpandemic period. Whole-genome sequence analysis of postpandemic A(H1N1)pdm09 viruses showed the circulation of clade 6 and clade 7 viruses. The hemagglutinin (HA) gene showed increased diversity compared with that in the pandemic phase.

10.
Genome Announc ; 1(6)2013 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-24285663

RESUMO

Systematic influenza virus surveillance has been carried out in India since 2004 and has revealed the cocirculation of type B lineages. The genetic diversity of influenza B viruses was observed when full-genome analysis was performed. In 2010, the cocirculation of multiple genotypes was observed.

11.
Waste Manag ; 32(8): 1521-7, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22542857

RESUMO

Municipal solid waste (MSW) incineration is a common and effective practice to reduce the volume of solid waste in urban areas. However, the byproduct of this process is a fly ash (IFA), which contains large quantities of toxic contaminants. The purpose of this research study was to analyze the chemical, physical and mechanical behaviors resulting from the gradual introduction of IFA to an alkaline activated coal fly ash (CFA) matrix, as a mean of stabilizing the incinerator ash for use in industrial construction applications, where human exposure potential is limited. IFA and CFA were analyzed via X-ray fluorescence (XRF), X-ray diffraction (XRD) and Inductive coupled plasma (ICP) to obtain a full chemical analysis of the samples, its crystallographic characteristics and a detailed count of the eight heavy metals contemplated in US Title 40 of the Code of Federal Regulations (40 CFR). The particle size distribution of IFA and CFA was also recorded. EPA's Toxicity Characteristic Leaching Procedure (TCLP) was followed to monitor the leachability of the contaminants before and after the activation. Also images obtained via Scanning Electron Microscopy (SEM), before and after the activation, are presented. Concrete made from IFA, CFA and IFA-CFA mixes was subjected to a full mechanical characterization; tests include compressive strength, flexural strength, elastic modulus, Poisson's ratio and setting time. The leachable heavy metal contents (except for Se) were below the maximum allowable limits and in many cases even below the reporting limit. The leachable Chromium was reduced from 0.153 down to 0.0045 mg/L, Arsenic from 0.256 down to 0.132 mg/L, Selenium from 1.05 down to 0.29 mg/L, Silver from 0.011 down to .001 mg/L, Barium from 2.06 down to 0.314 mg/L and Mercury from 0.007 down to 0.001 mg/L. Although the leachable Cd exhibited an increase from 0.49 up to 0.805 mg/L and Pd from 0.002 up to 0.029 mg/L, these were well below the maximum limits of 1.00 and 5.00 mg/L, respectively.


Assuntos
Cinza de Carvão/química , Incineração , Cinza de Carvão/toxicidade , Força Compressiva , Materiais de Construção , Módulo de Elasticidade , Concentração Máxima Permitida , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Poluição Química da Água/análise , Difração de Raios X
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