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BACKGROUND & OBJECTIVES: As India and other developing countries are scaling up isoniazid preventive therapy (IPT) for people living with HIV (PLHIV) in their national programmes, we studied the feasibility and performance of IPT in terms of treatment adherence, outcome and post-treatment effect when given under programmatic settings. METHODS: A multicentre, prospective pilot study was initiated among adults living with HIV on isoniazid 300 mg with pyridoxine 50 mg after ruling out active tuberculosis (TB). Symptom review and counselling were done monthly during IPT and for six-month post-IPT. The TB incidence rate was calculated and risk factors were identified. RESULTS: Among 4528 adults living with HIV who initiated IPT, 4015 (89%) successfully completed IPT. IPT was terminated in 121 adults (3%) due to grade 2 or above adverse events. Twenty five PLHIVs developed TB while on IPT. The incidence of TB while on IPT was 1.17/100 person-years (p-y) [95% confidence interval (CI) 0.8-1.73] as compared to TB incidence of 2.42/100 p-y (95% CI 1.90-3.10) during the pre-IPT period at these centres (P=0.017). The incidence of TB post-IPT was 0.64/100 p-y (95% CI 0.04-1.12). No single factor was significantly associated with the development of TB. INTERPRETATION & CONCLUSIONS: Under programmatic settings, completion of IPT treatment was high, adverse events minimal with good post-treatment protection. After ruling out TB, IPT should be offered to all PLHIVs, irrespective of their antiretroviral therapy (ART) status. Scaling-up of IPT services including active case finding, periodic counselling on adherence and re-training of ART staff should be prioritized to reduce the TB burden in this community.
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Infecciones por VIH , Tuberculosis , Adulto , Antituberculosos/efectos adversos , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Humanos , Incidencia , India/epidemiología , Isoniazida/efectos adversos , Proyectos Piloto , Estudios Prospectivos , Tuberculosis/tratamiento farmacológico , Tuberculosis/epidemiología , Tuberculosis/prevención & controlRESUMEN
BACKGROUND: WHO recommends the use of a simplified symptom-based algorithm for screening for tuberculosis (TB) among people living with HIV (PLHIV). We assessed the feasibility and effectiveness of this algorithm and determined the prevalence and incidence of TB among PLHIV attending antiretroviral treatment (ART) centres in India. METHODS: We did a prospective multicentric implementation research study in four states of India. To rule out TB, we administered the WHO symptom-screen algorithm to all PLHIV every month for 6 months. If they were found to be symptomatic any time during this period, they were referred for investigations for TB. A case of TB diagnosed during the first month of screening was taken as a prevalent case while those detected TB in the subsequent 5 months were considered cases of incident TB. We calculated the incidence rate using the person-years method. Results . Between May 2012 and October 2013, a total of 6099 adults and 1662 children living with HIV were screened for TB at the ART centres of four states. Of the 6099 adult PLHIV, 1815 (30%) had at least one symptom suggestive of TB, of whom only 634 (35%) were referred for investigations of TB. Of those referred, 97 (15%) PLHIV were diagnosed with TB. Overall, the prevalence of undiagnosed TB was 0.84 person-years and in the subsequent period, the incidence of TB was 2.4/100 person-years (95% CI 1.90-3.10). Among 1662 children, 434 (26%) had at least one symptom suggestive of TB. But only 57 (13%) children were referred for investigations of TB and 13 (23%) of them were diagnosed with TB. The prevalence of TB among children was 0.5% and its incidence among them was 2.7/100 person-years (95% CI 1.60-4.30). CONCLUSION: Prevalence and incidence of TB is high among PLHIV attending ART centres. This emphasizes the need to strengthen regular screening for symptoms of TB and further referral of those symptomatic for diagnosis of TB.
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Infecciones por VIH/complicaciones , Tamizaje Masivo/métodos , Tuberculosis/diagnóstico , Adolescente , Adulto , Niño , Estudios de Factibilidad , Femenino , Infecciones por VIH/inmunología , Humanos , Incidencia , India/epidemiología , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Prospectivos , Tuberculosis/epidemiología , Tuberculosis/inmunologíaRESUMEN
A diamine functionalized cubic mesostructured KIT-6 (N-KIT-6) has been prepared by post-synthetic method using calcined mesoporous KIT-6 with a diamine source, i.e., N-'[3-(tri methoxysilyl)- propyl]'ethylenediamine. The KIT-6 mesoporous silica used for N-KIT-6 was synthesized under weak acidic hydrothermal method using bitemplates, viz., Pluronic P123 and 1-butanol. The synthesized mesoporous materials, KIT-6 and N-KIT-6, have been characterized by the relevant instrumental techniques such as SAXS, N2 sorption isotherm, FT-IR, SEM, TEM and TGA to prove the standard mesoporous materials with the identification of diamine groups. The characterized mesoporous materials, KIT-6 and N-KIT-6, have been extensively used in the potential application of controlled drug delivery, where ibuprofen (IBU) employed as a model drug. The rate of IBU adsorption and release was monitored by UV vis-spectrometer. On the basis of the experimental results of controlled drug delivery system, the results of IBU adsorption and releasing rate in N-KIT-6 are higher than those of KIT-6 because of the higher hydrophobic nature as well as rich basic sites on the surface of inner pore wall silica.
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Analgésicos no Narcóticos , Diaminas/química , Ibuprofeno , Dióxido de Silicio , Analgésicos no Narcóticos/química , Analgésicos no Narcóticos/farmacocinética , Analgésicos no Narcóticos/farmacología , Preparaciones de Acción Retardada/química , Preparaciones de Acción Retardada/farmacocinética , Preparaciones de Acción Retardada/farmacología , Ibuprofeno/química , Ibuprofeno/farmacocinética , Ibuprofeno/farmacología , Porosidad , Dióxido de Silicio/química , Dióxido de Silicio/farmacocinética , Dióxido de Silicio/farmacologíaRESUMEN
The Ce1-xMnxO2 nanocatalysts (x = 0.25, 0.50 and 0.75 wt.%) were synthesized by sol-gel method. The catalysts were characterized using various techniques such as XRD, N2 sorption study, DRSUV-Vis, TPR, SEM and TEM. The incorporation of Mn ions into the ceria lattice was confirmed by XRD analysis. DRUV-Vis spectra confirm the presence of Ce3+ ions in the lattice of Ce1-xMnxO2. H2-TPR study revealed the oxygen storage capacity of the catalyst. The 3D flowerlike morphology of the nanocatalysts was confirmed from FESEM and HRTEM images. The catalytic activity was tested for the vapor phase oxidation of cyclohexane using air as an oxidant. The key reaction parameters were varied to study the stability, activity and selectivity of the catalysts. The study concluded that suitable amount of manganese content is essential for the selective oxidation of cyclohexane at low temperature and Ce0.25Mn0.75O2 is the most suitable catalyst for high conversion and selectivity under the given reaction conditions. The activity of the catalyst is correlated with the characterization results.
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Hard donor atoms (N and O) containing macrocyclic ligand was synthesized and further functionalized with mesoporous SBA-15 materials by chemical modification method. The modification was achieved by the immobilization of 3-chloropropyltriethoxysilane (CIPTES) onto mesoporous silica surface followed by post grafting route. The resulting material (Py-Cy-SBA-15) has been characterized by low angle X-ray diffraction (XRD), nitrogen adsorption-desorption isotherm, Fourier-transform infrared (FT-IR) spectroscopy, 29Si and 13C CP MAS NMR spectroscopic analyses, Thermogravimetric analysis (TGA) and elemental analysis. The long range orders of the materials were identified by transmission electron microscopy (TEM). The functionalized material was employed to the heavy metal ions adsorption from aqueous solution containing Cu2+, Co2+, Zn2+, Cd2+ and Cr2+. The prepared hybrid material showed high selectivity and adsorption capacity for Co2+ ion at pH 8.0.
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Cobalto/química , Nanoestructuras/química , Agua de Mar/química , Dióxido de Silicio/química , Contaminantes Químicos del Agua/química , Adsorción , Cobalto/análisis , Ligandos , Metales Pesados/análisis , Metales Pesados/química , Modelos Químicos , Contaminantes Químicos del Agua/análisisRESUMEN
Light-induced photocatalytic degradation of ceftiofur sodium (CFS) has been assessed in the presence of plasmonic zinc oxide nanostructures (ZnONSTs), like, ZnO nanoparticles, ZnO nanorods (ZnONRs) and ZnO nanoflowers (ZnONFs). Silver nanoparticles (Ag NPs) loaded ZnO nanostructures (Ag-ZnONSTs) are obtained through seed-assisted chemical reaction followed by chemical reduction of silver. The surface modification of ZnO nanostructures by Ag NPs effectually altered their optical properties. Further, the surface plasmonic effect of Ag NPs facilitates visible light absorption by ZnONSTs and improved the photogenerated electron and hole separation, which makes the ZnONSTs a more active photocatalyst than TiO2 (P25) nanoparticles. Especially, Ag-ZnONRs showed higher CFS oxidation rate constant (k' = 4.6 × 10-4 s-1) when compared to Ag-ZnONFs (k' = 2.8 × 10-4 s-1) and Ag-ZnONPs (k' = 2.5 × 10-4 s-1), owing to their high aspect ratio (60:1). The unidirectional transport of photogenerated charge carriers on the Ag-ZnONRs may be accountable for the observed high photocatalytic oxidation of CFS. The photocatalytic oxidation of CFS mainly proceeds through â¢OH radicals generated on the Ag-ZnONRs surface under light illumination. In addition, heterogeneous activation of peroxymonosulfate by Ag-ZnONRs accelerates the rate of photocatalytic mineralization of CFS. The quantification of oxidative radicals supports the proposed CFS oxidation mechanism. Stability studies of plasmonic Ag-ZnONSTs strongly suggests that it could be useful to clean large volume of pharmaceutical wastewater under direct solar light irradiation.
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Nanopartículas del Metal , Óxido de Zinc , Humanos , Óxido de Zinc/química , Plata/química , Iluminación , Nanopartículas del Metal/química , Luz , CatálisisRESUMEN
The X-ray structures of new crystal forms of peptidyl-tRNA hydrolase from M. tuberculosis reported here and the results of previous X-ray studies of the enzyme from different sources provide a picture of the functionally relevant plasticity of the protein molecule. The new X-ray results confirm the connection deduced previously between the closure of the lid at the peptide-binding site and the opening of the gate that separates the peptide-binding and tRNA-binding sites. The plasticity of the molecule indicated by X-ray structures is in general agreement with that deduced from the available solution NMR results. The correlation between the lid and the gate movements is not, however, observed in the NMR structure.
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Hidrolasas de Éster Carboxílico/química , Mycobacterium tuberculosis/enzimología , Cristalografía por Rayos X , Modelos Moleculares , Resonancia Magnética Nuclear Biomolecular , Estructura Terciaria de Proteína , Homología Estructural de ProteínaRESUMEN
ZnO hexagonal tube and ZnO/r-GO nanocomposites were synthesized by hydrothermal method and the nanostructures were characterized by XRD, UV-DRS, PL, FTIR, FESEM, and TEM techniques. The main violet emission peak of the synthesized nanostructures is due to the transition between interstitial zinc and hole (valence band) of ZnO. The potential of ZnO/r-GO nanocomposite was evaluated using methyl orange (MO) and rhodamine-B (RhB), and the results were compared with the activity of synthesized ZnO nanostructures. More than 95% of MO and RhB were by ZnO/r-GO nanocomposite and it was found to be higher than that of ZnO hexagonal tube. The degradation MO and RhB were found to follow first-order kinetics and it has a rate constant of 7.68 × 10-2and 7.83 × 10-2 min-1, respectively. These results are mainly due to the enhanced charge transport property. Trapping experiments show that superoxide radical anion and hydroxide radicals are chief species responsible for the degradation of MO and RhB. The chemical stability of the nanocomposite was evaluated by cycle test experiments and it reveals that the catalyst can be reused up to few cycles without considerable loss of photocatalytic activity. This work affords a simple stratagem to integrate ZnO hexagonal tubes and r-GO nanosheets to construct effective catalysts for the degradation of organic compounds.
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Contaminantes Ambientales , Nanocompuestos , Contaminantes Químicos del Agua , Óxido de Zinc , LuzRESUMEN
Plant pathology has developed a wide range of concepts and tools for improving plant disease management, including models for understanding and responding to new risks from climate change. Most of these tools can be improved using new advances in artificial intelligence (AI), such as machine learning to integrate massive data sets in predictive models. There is the potential to develop automated analyses of risk that alert decision-makers, from farm managers to national plant protection organizations, to the likely need for action and provide decision support for targeting responses. We review machine-learning applications in plant pathology and synthesize ideas for the next steps to make the most of these tools in digital agriculture. Global projects, such as the proposed global surveillance system for plant disease, will be strengthened by the integration of the wide range of new data, including data from tools like remote sensors, that are used to evaluate the risk ofplant disease. There is exciting potential for the use of AI to strengthen global capacity building as well, from image analysis for disease diagnostics and associated management recommendations on farmers' phones to future training methodologies for plant pathologists that are customized in real-time for management needs in response to the current risks. International cooperation in integrating data and models will help develop the most effective responses to new challenges from climate change.
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Inteligencia Artificial , Macrodatos , Agricultura , Cambio Climático , Aprendizaje AutomáticoRESUMEN
INTRODUCTION: Latarjet procedure is commonly performed for recurrent anterior shoulder instability with glenoid side bone loss. Classic Latarjet procedure can be performed using specially designed drill guides, jigs, or by freehand technique. Here we have described a technical note on classic Latarjet procedure performed with freehand technique utilizing simple rulers and caliper. The functional and radiological outcomes of our patients have also been analysed. MATERIAL AND METHODS: 149 open classic Latarjet procedures were performed using our technique between March 2015 and July 2018. The mean age of the patients was 32.95 years (Range 22-59 years). The functional outcome of the patients was measured using Western Ontario Shoulder Instability (WOSI) and Oxford Shoulder Instability Score (OSIS) at 2 years of follow-up. Screw and graft positioning were studied in 24 consecutive patients with a postoperative computed tomography (CT) scan. RESULTS: There was no incidence of recurrent subluxation or dislocation post-surgery. Mean OSIS score increased from 15.63 ± 3.20 preoperatively to 42.44 ± 3.88 postoperatively (p value < 0.05). WOSI score decreased significantly from 62.54% ± 8.24 to 10.26 ± 6.33 postoperatively at 2-year follow-up (p value < 0.05). Postoperative CT scan also showed satisfactory screw placement in all patients. CONCLUSION: Open Latarjet procedure performed using freehand technique provides good functional and radiological outcomes in patients with recurrent anterior shoulder instability with glenoid side bone loss. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s43465-021-00385-7.
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A secreted lectin, Rv1419, from Mycobacterium tuberculosis has been cloned, expressed, purified and crystallized and the crystals have been characterized. This represents the first X-ray investigation of a lectin or lectin-like molecule from the pathogen. The cubic crystals contain one molecule in the asymmetric unit. Sequence comparisons indicate that the lectin has a ß-trefoil fold and belongs to a well characterized family of carbohydrate-binding modules. Structural analysis of the crystals is in progress.
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Proteínas Bacterianas/química , Proteínas Bacterianas/aislamiento & purificación , Lectinas/química , Lectinas/metabolismo , Mycobacterium tuberculosis/química , Proteínas Bacterianas/metabolismo , Clonación Molecular , Cristalización , Cristalografía por Rayos X , Electroforesis en Gel de Poliacrilamida , Lectinas/aislamiento & purificaciónRESUMEN
Following the successful eradication of rinderpest, the World Organization of Animal Health (OIE) and the Food and Agriculture Organization (FAO) have set a goal to eradicate peste des petits ruminants (PPR) globally by 2030. Vaccination is being taken forward as the key strategy along with epidemiological surveillance to target vaccination efforts and eradicate the disease. PPR is highly contagious and is generally spread by aerosolized droplets and close contact. Currently, two live attenuated vaccines (Nigeria 75/1 and Sungri 96) are in use, and administered subcutaneously to prevent transmission of PPR and protect vaccinated animals. Though the target cells that support primary replication of PPR vaccine strains are largely unknown, it is hypothesized that the immune response could be intensified following intranasal vaccine delivery as this route mimics the natural route of infection. This study aims to compare the immunogenicity and protective efficacy of the two currently available live attenuated PPR vaccines following subcutaneous and intranasal routes of vaccination in target species. Groups of five goats were vaccinated with live attenuated PPR vaccines (Nigeria 75/1 and Sungri 96) by either the subcutaneous or intranasal route, and 28 days later challenged intranasally with virulent PPR virus. All vaccinated animals regardless of vaccination route produced PPRV-specific antibodies post-vaccination. Following challenge, all goats were protected from clinical disease, and vaccination was considered to have induced sterilizing immunity. This study demonstrates that the intranasal route of vaccination is as effective as the subcutaneous route of vaccination when using available live attenuated PPR vaccines.
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Following the successful eradication of rinderpest, the World Organization of Animal Health (OIE) and the Food and Agriculture Organisation (FAO) have set a goal to globally eradicate Peste des petits ruminants (PPR) by 2030. To support the eradication programme we have quantified the levels of PPR virus (PPRV) nucleic acid excreted in body fluids (blood, feces, saliva, nasal and eye swabs) of PPRV-infected goats to ascertain which days post-infection animals are potentially infectious, and hence direct quarantine activities. The data will also indicate optimal sample strategies to assess presence of PPR infection in the naturally infected herd. Peak PPRV nucleic acid detection in different bodily fluids was between 5 and 10 days post-infection. As such, this period must be considered the most infectious period for contact transmission, although high viral load was observed through RNA detection in nasal excretions from two days post-infection until at least two weeks post-infection. Percentage sample positivity was low both in eye swabs and saliva samples during the early stage of infection although RNA was detected as late as two weeks post-infection. From the individual animal data, PPRV was detected later post-infection in fecal material than in other body fluids and the detection was intermittent. The results from this study indicate that nasal swabs are the most appropriate to sample when considering molecular diagnosis of PPRV.
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Erradicación de la Enfermedad , Brotes de Enfermedades/veterinaria , Enfermedades de las Cabras/virología , Peste de los Pequeños Rumiantes/prevención & control , Virus de la Peste de los Pequeños Rumiantes/aislamiento & purificación , ARN Viral/análisis , ARN Viral/genética , Animales , Brotes de Enfermedades/prevención & control , Heces/virología , Cabras , Masculino , Nariz/virología , Peste de los Pequeños Rumiantes/sangre , Virus de la Peste de los Pequeños Rumiantes/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Saliva/virologíaRESUMEN
Peptidyl-tRNA hydrolase cleaves the ester bond between tRNA and the attached peptide in peptidyl-tRNA in order to avoid the toxicity resulting from its accumulation and to free the tRNA available for further rounds in protein synthesis. The structure of the enzyme from Mycobacterium tuberculosis has been determined in three crystal forms. This structure and the structure of the enzyme from Escherichia coli in its crystal differ substantially on account of the binding of the C terminus of the E. coli enzyme to the peptide-binding site of a neighboring molecule in the crystal. A detailed examination of this difference led to an elucidation of the plasticity of the binding site of the enzyme. The peptide-binding site of the enzyme is a cleft between the body of the molecule and a polypeptide stretch involving a loop and a helix. This stretch is in the open conformation when the enzyme is in the free state as in the crystals of M. tuberculosis peptidyl-tRNA hydrolase. Furthermore, there is no physical continuity between the tRNA and the peptide-binding sites. The molecule in the E. coli crystal mimics the peptide-bound enzyme molecule. The peptide stretch referred to earlier now closes on the bound peptide. Concurrently, a channel connecting the tRNA and the peptide-binding site opens primarily through the concerted movement of two residues. Thus, the crystal structure of M. tuberculosis peptidyl-tRNA hydrolase when compared with the crystal structure of the E. coli enzyme, leads to a model of structural changes associated with enzyme action on the basis of the plasticity of the molecule.
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Hidrolasas de Éster Carboxílico/química , Hidrolasas de Éster Carboxílico/metabolismo , Mycobacterium tuberculosis/enzimología , Cristalografía por Rayos X , Escherichia coli/enzimología , Modelos Moleculares , Estructura Secundaria de Proteína , Aminoacil-ARN de Transferencia/metabolismoRESUMEN
A BacMam baculovirus was designed in our laboratory to express the reporter protein secreted alkaline phosphatase (SEAP) driven by the immediate early promoter of human cytomegalovirus promoter (CMV). In vitro tests have been carried out using this recombinant baculovirus to study the secreted protein in two cell lines and under various culture conditions. The transductions were carried out on two commonly used mammalian cell lines namely the human embryonic kidney (HEK 293A) and Chinese hamster ovary (CHO-K1). Initial studies clearly demonstrated that the transient expression of SEAP was at least 10-fold higher in the HEK 293 cells than the CHO cells under equivalent experimental conditions. Factorial design experiments were done to study the effect of different parameters such as cell density, MOI, and the histone deacetylase inhibitor, trichostatin A concentration. The multiplicity of infection (MOI) and the cell density were found to have the most impact on the process. The enhancer trichostatin A also showed some positive effect. The production of secreted protein in a batch reactor was studied using the Wave disposable bioreactor system. A semi-continuous perfusion process was developed to extend the period of gene expression in mammalian cells using a hollow fiber bioreactor system (HFBR). The growth of cells and viability in both systems was monitored by offline analyses of metabolites. The expression of recombinant protein could be maintained over an extended period of time up to 30 days in the HFBR.
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Fosfatasa Alcalina/metabolismo , Baculoviridae/metabolismo , Reactores Biológicos , Transducción Genética , Análisis de Varianza , Animales , Células CHO , Línea Celular , Cricetinae , Cricetulus , Filtración , Vectores Genéticos , Humanos , InsectosRESUMEN
Highly catalytic two dimensional and metal-doped two-dimensional nanomaterials (MoS2 and NiMoS) were deposited over free-standing graphene (FSG) paper using electrodeposition method and subsequently used as a counter electrode in quasi solid-state dye-sensitized solar cells (q-DSSCs). The replacement of FTO by FSG facilitates high electrical conductivity and electrodeposited metal sulphides provide electrocatalytic activity. The morphology, structural phase formation and chemical composition of FSG-MoS2 and FSG-NiMoS were investigated using FESEM, XRD, Raman and XPS analysis. The electrochemical behavior of metal sulphide decorated FSG cathodes is investigated using an electrochemical workstation and their effects on the photo-conversion efficiency of DSSCs were assessed. NiMoS with FSG substrate is an intriguing counter electrode material that can be utilized at low fabrication cost than the conventional platinum-based counter electrodes. FSG along with the metallic-two dimensional nanoparticles (NiMoS) functions as an effective catalytic material thereby allowing DSSCs to achieve enhanced efficiency of â¼7% to provide better alternative of FTO and Pt.
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The mesoporous MnSBA-15 materials with different n(Si)/n(Mn) ratios of 4, 8, 20, and 50 have been synthesized, for the first time, using manganese nitrate tetrahydrate and Pluronic 123 triblock polymer [(EO)20(PO)70(EO)20] by simply adjusting the molar ratio of water to hydrochloric acid (n(H2O)/n(HCl)) under direct hydrothermal conditions. For the effect of structural and textural properties with incorporation of manganese, the MnSBA-15 has been synthesized with different synthesis temperatures at the fixed molar ratios of n(Si)/n(Mn) = 4 and n(H2O)/n(HCl) = 295 in the synthesis gel. The hydrothermal and thermal stabilities of MnSBA-15 have also been investigated. The calcined MnSBA-15 materials prepared have been characterized by ICP-AES, XRD, N2 adsorption, ESR, FE-SEM, and TEM. The ICP-AES studies show a higher amount of manganese incorporation on the silica pore walls, as MnSBA-15 with a n(Si)/n(Mn) ratio up to 2.2 can be successfully prepared at a fixed n(H2O)/n(HCl) molar ratio of 295 by adjusting the ratios of n(Si)/n(Mn) in the synthesis gel. The structural and textural properties of calcined MnSBA-15 prepared can be found by the results of XRD and N2 adsorption. The investigation of ESR results clearly describe the effect of structure and Mn species coordination on the SBA-15 silica pore walls while the uniform pore diameter and rope-like hexagonal mesoporous structure of MnSBA-15 can be identified by TEM and FE-SEM images. With increasing synthesis temperature, an increase the unit cell parameter, pore size, and pore volume and a decrease the specific surface area and pore wall thickness of MnSBA-15 can be obviously noted by the results of XRD and N2 adsorption. The hexagonal MnSBA-15 materials prepared could be tested as catalysts in epoxidation of trans-stilbene to produce trans-stilbene oxide under various optimal conditions while their catalytic properties could also be compared to the results of MnMCM-41 and ZrMnMCM-41.
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Peptidyl-tRNA hydrolase catalyses the cleavage of the ester link between the peptide and the tRNA in peptidyl-tRNAs that, for various reasons, have dropped off the translating ribosomes. This enzyme from Mycobacterium tuberculosis has been crystallized in three related but distinct forms: P2(1)2(1)2(1), unit-cell parameters a = 36.30, b = 61.85, c = 73.97 A, P2(1), a = 35.83, b = 73.79, c = 59.79 A, beta = 92.3 degrees , and P2(1)2(1)2(1), a = 35.84, b = 57.06, c = 72.59 A. X-ray data have been collected from all three forms.
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Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Hidrolasas de Éster Carboxílico/química , Hidrolasas de Éster Carboxílico/genética , Mycobacterium tuberculosis/enzimología , Mycobacterium tuberculosis/genética , Proteínas Bacterianas/biosíntesis , Proteínas Bacterianas/aislamiento & purificación , Hidrolasas de Éster Carboxílico/biosíntesis , Hidrolasas de Éster Carboxílico/aislamiento & purificación , Clonación Molecular , Cristalización , Cristalografía por Rayos X/métodos , Regulación Bacteriana de la Expresión GénicaRESUMEN
Sunlight assisted reduction of silver ions were accomplished for the synthesis of silver nanoparticles incorporated within the mesoporous silicate framework of zeolite Y. The zeolite-Y and AgNP/Zeo-Y were characterized by field emission scanning electron microscopy, transmission electron microscopy, N2 adsorption-desorption BET isotherm and X-ray diffraction techniques. The incorporation of silver nanoparticles within the porous framework was further confirmed by cyclic voltammetry and electrochemical impedance spectroscopy. An enhanced electrocatalytic oxidation of biologically important molecules like dopamine and uric acid using AgNP/Zeo-Y modified glassy carbon electrode has been developed. A simultaneous oxidation of DA and UA peaks were obtained at +0.31V and +0.43V (vs. Ag/AgCl) using AgNP/Zeo-Y/GCE under the optimum experimental condition. A well-resolved peak potential window (~120mV) for the oxidation of both DA and UA were observed at AgNP/Zeo-Y/GCE system. The calibration curves for DA and UA were obtained within the dynamic linear range of 0.02×10(-6) to 0.18×10(-6)M (R(2)=0.9899) and 0.05×10(-6) to 0.7×10(-6)M (R(2)=0.9996) and the detection limits were found to be 1.6×10(-8)M and 2.51×10(-8)M by using differential pulse voltammetry (DPV) method. The proposed method was successfully applied for the determination of both DA and UA in human urine samples with a related standard deviation was <3%, and n=5 using the standard addition method.
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Técnicas de Química Analítica/métodos , Dopamina/orina , Técnicas Electroquímicas , Nanopartículas del Metal/química , Plata/química , Luz Solar , Ácido Úrico/orina , Zeolitas/química , Carbono/química , Catálisis , Técnicas de Química Analítica/instrumentación , Espectroscopía Dieléctrica , Electrodos , Humanos , Concentración de Iones de Hidrógeno , Límite de Detección , Oxidación-Reducción , Porosidad , Reproducibilidad de los Resultados , Difracción de Rayos XRESUMEN
BACKGROUND: Information on the follow-up of HIV-infected children enrolled into preantiretroviral therapy (Pre-ART) care under routine program settings is limited in India. Knowledge on the magnitude of loss to follow-up (LFU) and its reasons will help programs to retain children in HIV care. We aimed to assess the proportion of LFU among children in Pre-ART care and its associated factors. METHODS: In this retrospective cohort study, we reviewed the records of all HIV-infected children (aged <15 years) registered from 2005 to 2012 at an ART center, Madurai, South India. LFU during Pre-ART care was defined as having not visited the ART center within a year of registration. RESULTS: Of 426 children enrolled in Pre-ART care, 211 (49%) were females and 301 (71%) were in the 5- to 14-year age group. At 1 year of registration, 348 (82%) were lost to follow-up. Of 348, 81 returned to care after 1 year of enrollment, whereas 267 (63% of all children) were permanently lost to follow-up. The proportion of LFU remained high from 2005 to 2012. WHO staging, CD4 count, and opportunistic infection were the significant factors associated with lost to follow-up on multivariate analysis. CONCLUSIONS: LFU was alarmingly high indicating poor clinical and programmatic monitoring among HIV-infected children enrolled in Pre-ART care. A system for active tracing of those missing a clinic appointment intensified supervision, and monitoring along with qualitative research is urgently needed. This will help to understand the exact reasons for LFU based on which effective interventions may be planned for reducing such losses.