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BACKGROUND: In this study, we designed a novel genetic circuit sensitive to Cd2+, Zn2+ and Pb2+ by mimicking the CadA/CadR operon system mediated heavy metal homeostasis mechanism of Pseudomonas aeruginosa. The regular DNA motifs on natural operon were reconfigured and coupled with the enhanced Green Fluorescent Protein (eGFP) reporter to develop a novel basic NOT type logic gate CadA/CadR-eGFP to respond metal ions mentioned above. A Genetically Engineered Microbial (GEM)-based biosensor (E.coli-BL21:pJET1.2-CadA/CadR-eGFP) was developed by cloning the chemically synthesised CadA/CadR-eGFP gene circuit into pJET1.2-plasmid and transforming into Escherichia coli (E. coli)-BL21 bacterial cells. RESULTS: The GEM-based biosensor cells indicated the reporter gene expression in the presence of Cd2+, Zn2+ and Pb2+ either singly or in combination. Further, the same biosensor cells calibrated for fluorescent intensity against heavy metal concentration generated linear graphs for Cd2+, Zn2+ and Pb2+ with the R2 values of 0.9809, 0.9761 and 0.9758, respectively as compared to non-specific metals, Fe3+ (0.0373), AsO43- (0.3825) and Ni2+ (0.8498) making our biosensor suitable for the detection of low concentration of the former metal ions in the range of 1-6 ppb. Furthermore, the GEM based biosensor cells were growing naturally within the concentration range of heavy metals, at 37 °C and optimum pH = 7.0 in the medium, resembling the characteristics of wildtype E.coli. CONCLUSION: Finally, the novel GEM based biosensor cells developed in this study can be applied for detection of targeted heavy metals in low concentration ranges (1-6 ppb) at normal bacterial physiological conditions.
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Técnicas Biossensoriais , Metais Pesados , Cádmio/metabolismo , Chumbo/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Calibragem , Metais Pesados/metabolismo , Zinco , Íons/metabolismoRESUMO
BACKGROUND: Distinct clinical presentations of interstitial lung disease (ILD) with the myositis-specific antibodies, including anti-synthetase antibodies, are well-recognized. However, the association between ILD and the myositis-associated antibodies, including anti-Ro52, is less established. Our objectives were to compare presenting phenotypes of patients with anti-Ro52 alone versus in combination with myositis-specific autoantibodies and to identify predictors of disease progression or death. METHODS: We performed a retrospective cohort study of 73 adults with ILD and a positive anti-Ro52 antibody. We report clinical features, treatment, and outcomes. RESULTS: The majority of patients with ILD and anti-Ro52 had no established connective tissue disease (78%), and one-third had no rheumatologic symptoms. Thirteen patients (17.8%) required ICU admission for respiratory failure, with 84.6% all-cause mortality. Of the 73 subjects, 85.7% had a negative SS-A, and 49.3% met criteria for idiopathic pneumonia with autoimmune features (IPAF). The 50 patients with anti-Ro52 alone were indistinguishable from patients with anti-Ro52 plus a myositis-specific autoantibody. ICU admission was associated with poor outcomes (HR 12.97, 95% CI 5.07-34.0, p < 0.0001), whereas rheumatologic symptoms or ANA > = 1:320 were associated with better outcomes (HR 0.4, 95% CI 0.16-0.97, p = 0.04, and HR 0.29, 95% CI 0.09-0.81, p = 0.03, respectively). CONCLUSIONS: Presentations of ILD with the anti-Ro52 antibody are heterogeneous, and outcomes are similar when compared to anti-Ro52 plus myositis-specific antibodies. Testing for anti-Ro52 may help to phenotype unclassifiable ILD patients, particularly as part of the serologic criteria for IPAF. Further research is needed to investigate treatment of ILD in the setting of anti-Ro52 positivity.
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Autoanticorpos/sangue , Doenças Pulmonares Intersticiais/sangue , Doenças Pulmonares Intersticiais/diagnóstico por imagem , Ribonucleoproteínas/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Seguimentos , Humanos , Unidades de Terapia Intensiva/tendências , Masculino , Pessoa de Meia-Idade , Admissão do Paciente/tendências , Estudos Retrospectivos , Resultado do Tratamento , Adulto JovemRESUMO
BACKGROUND: The increased transmission of multidrug-resistant (MDR) tuberculosis (TB) poses a challenge to tuberculosis prevention and control in Sri Lanka. Isoniazid (INH) is a key element of the first line anti tuberculosis treatment regimen. Resistance to INH may lead to development of MDR TB. Therefore, early detection of INH resistance is important to curb spread of resistance. Due to the limited availability of rapid molecular methods for detection of drug resistance in Sri Lanka, this study was aimed at developing a simple and rapid gold nanoparticle (AuNP) based lateral flow strip for the simultaneous detection of the most common INH resistance mutation (katG S315 T, 78.6%) and Mycobacterium tuberculosis (MTb). METHODS: Lateral flow strip was designed on an inert plastic backing layer containing a sample pad, nitrocellulose membrane and an absorption pad. Biotin labeled 4 capture probes which separately conjugated with streptavidin were immobilized on the nitrocellulose. The test sample was prepared by multiplex PCR using primers to amplify codon 315 region of the katG gene and MTb specific IS6110 region. The two detection probes complementary to the 5' end of each amplified fragment was conjugated with gold nanoparticles (20 nm) and coupled with the above amplified PCR products were applied on the sample pad. The hybridization of the amplified target regions to the respective capture probes takes place when the sample moves towards the absorption pad. Positive hybridization is indicated by red colour lines. RESULTS: The three immobilized capture probes on the strip (for the detection of TB, katG wild type and mutation) were 100 and 96.6% specific and 100 and 92.1% sensitive respectively. CONCLUSION: The AuNP based lateral flow assay was capable of differentiating the specific mutation and the wild type along with MTb identification within 3 h.
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Doenças Transmissíveis/diagnóstico , Nanotecnologia/métodos , Tuberculose Resistente a Múltiplos Medicamentos/diagnóstico , Antituberculosos/uso terapêutico , Proteínas de Bactérias/genética , Catalase/genética , Doenças Transmissíveis/tratamento farmacológico , DNA Bacteriano/isolamento & purificação , DNA Bacteriano/metabolismo , Ouro/química , Humanos , Isoniazida/uso terapêutico , Limite de Detecção , Nanopartículas Metálicas/química , Reação em Cadeia da Polimerase Multiplex , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/isolamento & purificação , Sri Lanka , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológicoRESUMO
This study reports on the effects of maternal protein malnutrition on baroreflex (BR) control of the heart rate and sympathetic nerve activity in the hypertensive male offspring of Wistar rat dams. Wistar rat dams were fed a normal protein (NP) control (17% protein) or a low protein (LP; 8% protein) diet during pregnancy and lactation, and their male offspring were studied when 90 days old. In these animals we evaluated spontaneous and induced BR control, the variability of the cardiovascular system and analyzed a direct recording of lumbar sympathetic nervous activity. The 90 day-old LP conscious rats had increased arterial pressure compared to NP, with enhanced low frequency oscillations of the systolic pressure, but no changes in the spontaneous and induced BR control of heart rate. In relation to nerve recordings, we observed similar values in terms of mean, frequency and amplitude between the groups. In addition, we noted that spontaneous and induced BR control of lumbar sympathetic activity in the LP group was similar to the control group. The data indicate that hypertension in the adult rat offspring subjected to perinatal protein malnutrition is not related to baroreflex dysfunction.
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Barorreflexo/fisiologia , Dieta com Restrição de Proteínas/efeitos adversos , Hipertensão/fisiopatologia , Desnutrição/fisiopatologia , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Animais , Feminino , Hipertensão/etiologia , Masculino , Desnutrição/complicações , Gravidez , Efeitos Tardios da Exposição Pré-Natal/etiologia , Distribuição Aleatória , Ratos , Ratos WistarRESUMO
We report the extraction of keratin nanofibers from the medulla of a parent yarn after denaturing the cuticle and cortex microstructures of a merino wool yarn. Controlled alkaline hydrolysis, followed by high-speed blending in acetic acid, allowed for the extraction of keratin protein nanofibers with an average diameter of 25 nm and a length of less than 3 µm. SEM and AFM analyses showed the removal of cuticle cells from the yarn. FT-IR and DSC analyses confirmed the hydrolysis and denaturation of the sheet protein matrix of cuticle cells. XPS analysis provided strong evidence for the gradual removal of the epicuticle, cuticle cells, and cortex of the hierarchical wool structure with an increase in alkaline hydrolysis conditions. It was confirmed that the merino wool yarn subjected to hydrolysis under alkaline conditions exposed its internal fibrillar surface. In an acetic acid medium, these fibrillar surfaces obtained a surface charge, which further supported the defibrillation of the structure into its individual nanofibrils during high-speed blending. The extracted nanostructures constitute mainly α-helical proteins. The morphology of the nanofibers is composed of a uniform circular cross-section based on the images obtained using AFM, TEM, and SEM. The extracted nanofibers were successfully fabricated into transparent sheets that can be used in several applications.
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The emergence of resistance in detrimental pathogenic bacteria towards well-recognized antibiotics has greatly impacted global medicine, consequently exploring potent antibacterial compounds is becoming a potential area of research. Although photocatalytic metal oxides have been extensively explored in this regard, their applicability is diminished due to the requirement of photon energy. Therefore, in our study, we explored the light-independent antibacterial effect of two unexplored titanium species, known as metatitanic acid (MTA) and potassium titanate, against Staphylococcus aureus, Escherichia coli, and Pseudomonas spp. using the disk diffusion method in Luria-Bertani agar medium, where the well-known antibiotic, gentamicin, was used as the positive control. These two titanium compounds were readily synthesized through a novel process which was originally developed for the extraction of TiO2 from ilmenite. The synthesized MTA was characterized using FT-IR, Raman spectroscopy, XRD, TGA, UV-visible spectroscopy, and SEM. According to our findings, both MTA and potassium titanate exhibited superior light-independent antibacterial properties, where for some concentrations, the effect was even greater than gentamicin. However, nano-TiO2 totally failed as an antibacterial compound against the tested three strains under dark conditions.
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In order to provide the first cytogenetic data of naturalized and threatened goat breeds from northeastern Brazil, cytogenetic analyses were carried out in individuals of Repartida and Moxotó breeds raised in Bahia and Ceará States. Males and females of both breeds had 2n = 60, with 29 autosomal acrocentric pairs plus the sex chromosome pair. The number of nucleolar organizer region (NOR)-bearing chromosomes ranged from 6 to 8 per metaphase in Moxotó and Repartida goats, respectively. The active NORs in Repartida individuals were located exclusively at the terminal regions of the long arms, as usually detected in Bovidae. Otherwise, Moxotó specimens presented a large autosomal pair with NORs on short arms. GC-rich heterochromatin was detected at the centromeres in both breeds, although polymorphic terminal C-bands were visualized on pair 25 in Moxotó. In addition, GC-rich regions were detected at the terminal regions of the long arms of a single pair in Repartida and of 20 chromosomes in Moxotó goats. The differences in both the number and/or position of Ag-NORs and GC-rich sites between Repartida and Moxotó breeds represent efficient cytogenetic markers that can be used in the identification and conservation of the genetic integrity of each lineage. In spite of the small effective population size of these breeds, chromosomal abnormalities related to drift or inbreeding effects were absent in the samples analyzed.
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Cromossomos/genética , Análise Citogenética , Marcadores Genéticos/genética , Cabras/genética , Animais , Brasil , Feminino , Heterocromatina/genética , Cariotipagem , MasculinoRESUMO
A new approach was used to produce electrically conductive polyamide yarns, employing an electroless plating technique, which involved stabilizing silver nanoparticles on the surface of the yarn using Sn2+. First, the [Ag(NH3)2]+ complex was reduced using Sn2+ to produce silver nanoparticle seed layers on the fiber surface, followed by a formaldehyde reduction. The nucleation and growth of silver nanoparticles on the fiber surface were observed through SEM images, demonstrating varying degrees of silver deposition depending on the silver concentration. This deposition variation was confirmed through XRD patterns, TGA data and UV-vis spectra. Additionally, XPS characterization showed the evolution of the chemical state of silver and tin during the silver reduction process. Electrical resistance revealed that the resistance per unit length of the yarn ranged from 3 ± 0.3 Ω cm-1 to 70 ± 6 Ω cm-1, depending on the silver concentration. The resulting silver-plated yarn was incorporated into a stretchable device, demonstrating stable resistance over multiple cycles. This method of fabricating conductive yarn has the potential to open up new possibilities in the design and manufacture of stretchable conductive devices for flexible electronics.
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BACKGROUND: Since ancient times, the essential element sulphur has played an important role in different medical fields. It is one of the main materials used in herbo-mineral pharmaceutics in Ayurveda. However, for Ayurvedic pharmaceutical preparations, the purity of sulphur is crucial in avoiding any harmful reactions and to enhance the medicinal quality. Therefore, it is subjected to a process called 'gandhaka shodhana' using cow's milk, ghee or occasionally plant extracts. The plant, Eclipta alba (L.) Hassak, containing many bioactive compounds, is one of the extracts known to be used in the 'shodhana' process of sulphur. However, in comparison to the laboratory purification method of sulphur neither the effect of this 'shodhana' process in removing impurities from sulphur nor its effect on the structure and morphology of sulphur has been evaluated. OBJECTIVES: This study identifies physical, morphological, and structural changes that occur in sulphur when it is subjected to the 'shodhana' process compared to the changes that occur in sulphur obtained after simple laboratory purification. METHODOLOGY: Both samples were characterized using Scanning Electron Microscopy, Energy Dispersive X-ray Spectroscopy, X-ray Diffraction, Differential Scanning Calorimetry, Thermogravimetric Analysis, Fourier Transform Infrared spectroscopy, and Raman spectroscopy. Observed physical changes such as colour, allotropic form, odour, hardness, transparency, and lustre of the samples were also determined using recommended techniques. RESULTS: Although the laboratory purification method separates the sulphur from physical and chemical impurities, Ayurveda 'shodhana' process with E. alba converts the sulphur into a more pharmaceutically suitable form by making it more nebulous and introducing higher brittleness, FT-IR data shows removal of chemical impurities from sulphur during 'shodhana' process in contrast to laboratory purified sample.
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Nano-zirconia (ZO) was synthesized using a microwave-assisted one-pot precipitation route. Two biopolymers, chitosan (CTS) and carboxymethyl cellulose were blended with ZO at different w/w ratios. The formulation with 30% w/w chitosan (ZO-CTS) was found to give enhanced uptake of F- and As(V). ZO and the most effective ZO-CTS system were characterized using Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy. These confirmed the formation of a composite system containing nanoparticles of 50 nm in size, in which ZO was present in the amorphous form. It was observed that the combination of ZO with CTS improved the F- and As(V) adsorption capacity most notably at pH 5.5. Fluoride adsorption by ZO-CTS followed the Freundlich isotherm model, with an adsorption capacity of 120 mg g-1. Adsorption of As(V) by ZO-CTS could be fitted with both the Langmuir and Freundlich isotherm models and was found to have a capacity of 14.8 mg g-1. Gravity filtration studies conducted for groundwater levels indicated the effectiveness of ZO-CTS in adsorbing As(V) and F- at a pH of 5.5. The ability of the ZO-CTS in removing Cd(II) and Pb(II) was also investigated, and no such enhancement was observed, and found the neat ZO was the most potent sorbent here.
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This study reveals the state-of-the-art fabrication of a tripolymer-based electrospun nanofiber (NF) system to enhance the release, solubility, and transdermal penetration of curcumin (Cur) with the aid of in situ release of infused castor oil (Co). In this regard, Cur-loaded Co-infused polyethylene oxide (PEO), ethyl cellulose (EC), and polyvinyl pyrrolidone (PVP) tripolymer-based NF systems were developed to produce a hybridized transdermal skin patch. Weight percentages of 1-4% Cur and 3-10% of Co were blended with PEO-EC-PEO and PEO-EC-PVP polymer systems. The prepared NFs were characterized by SEM, TEM, FT-IR analysis, PXRD, differential scanning calorimetry (DSC), and XPS. Dialysis membranes and vertical Franz diffusion cells were used to study the in vitro drug release and transdermal penetration, respectively. The results indicated that maintaining a Cur concentration of 1-3 wt % with 3 wt % Co in both PEO-EC-Co-Cur@PEO and PEO-EC-Co-Cur@PVP gave rise to nanofibers with lowered diameters (144.83 ± 48.05-209.26 ± 41.80 nm and 190.20 ± 59.42-404.59 ± 45.31 nm). Lowered crystallinity observed from the PXRD patterns and the disappearance of exothermic peaks corresponding to the melting point of Cur suggested the formation of an amorphous NF structure. Furthermore, the XPS data revealed that the Cur loading will possibly take place at the inner interface of PEO-EC-Co-PEO and PEO-EC-Co-PVP NFs rather than on the surface. The beneficiary role of Co on the release and dermal penetration of Cur was further confirmed from the respective release data which indicated that PEO-EC-Co-Cur@PEO would lead to a rapid release (4-5 h), while PEO-EC-Co-Cur@PVP would lead to a sustained release over a period of 24 h in the presence of Co. Transdermal penetration of the released Cur was further evidenced with the development of color in the receiver compartment of the diffusion cell. DPPH results further corroborated that a sustained antioxidant activity is observed in the released Cur where the free-radical scavenging activity is intact even after subjecting to an electrospinning process and under extreme freeze-thaw conditions.
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Visceral leishmaniosis is a neglected tropical disease. We evaluated the spatial distribution of cases of visceral leishmaniosis in the state of Alagoas, Brazil. All cases of VL, registered by the health department, were analyzed and georeferenced. Results: Between 2008 and 2017, 97.1% of the municipalities presented sporadic classification of transmission. With temporal evolution, the incidence of cases of visceral leishmaniosis was concentrated in most municipalities in the microregion of Santana do Ipanema-AL. Space-time analysis, if considered, may promote the improvement of surveillance and control actions of visceral leishmaniosis.
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Leishmaniose Visceral , Brasil/epidemiologia , Cidades , Humanos , Leishmaniose Visceral/epidemiologia , Doenças Negligenciadas/epidemiologia , Análise Espaço-TemporalRESUMO
Meta-analysis of results from multiple studies could lead to more precise quantitative trait loci (QTL) position estimates compared to the individual experiments. As the raw data from many different studies are not readily available, the use of results from published articles may be helpful. In this study, we performed a meta-analysis of QTL on chromosome 4 in pig, using data from 25 separate experiments. First, a meta-analysis was performed for individual traits: average daily gain and backfat thickness. Second, a meta-analysis was performed for the QTL of three traits affecting loin yield: loin eye area, carcass length and loin meat weight. Third, 78 QTL were selected from 20 traits that could be assigned to one of three broad categories: carcass, fatness or growth traits. For each analysis, the number of identified meta-QTL was smaller than the number of initial QTL. The reduction in the number of QTL ranged from 71% to 86% compared to the total number before the meta-analysis. In addition, the meta-analysis reduced the QTL confidence intervals by as much as 85% compared to individual QTL estimates. The reduction in the confidence interval was greater when a large number of independent QTL was included in the meta-analysis. Meta-QTL related to growth and fatness were found in the same region as the FAT1 region. Results indicate that the meta-analysis is an efficient strategy to estimate the number and refine the positions of QTL when QTL estimates are available from multiple populations and experiments. This strategy can be used to better target further studies such as the selection of candidate genes related to trait variation.
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Cromossomos de Mamíferos/genética , Locos de Características Quantitativas , Suínos/genética , Tecido Adiposo , Criação de Animais Domésticos , Animais , Peso Corporal/genética , Mapeamento Cromossômico , Genótipo , Carne , Repetições de Microssatélites , FenótipoRESUMO
Capacitive deionization (CDI) is a trending water desalination method during which the impurity ions in water can be removed by electrosorption. In this study, nano-manganese dioxide (MnO2) and reduced graphene oxide (rGO)-doped polyacrylonitrile (PAN) composite fibers are fabricated using an electrospinning technique. The incorporation of both MnO2 and rGO nanomaterials in the synthesized fibers was confirmed by transmission electron microscopy (TEM), scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDX). The electrochemical characteristics of electrode materials were examined using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and constant current charge-discharge cycles (CCCDs). The specific capacitance of the PAN electrode increased with increasing MnO2 and rGO contents as well as when thermally treated at 280 °C. Thermally treated composite fibers with 17% (w/w) MnO2 and 1% (w/w) rGO (C-rGOMnPAN) were observed to have the best electrochemical performance, with a specific capacitance of 244 F g-1 at a 10 mV s-1 scan rate. The electrode system was used to study the removal of sodium chloride (NaCl), cadmium (Cd2+) and lead (Pb2+) ions. Results indicated that NaCl showed the highest electrosorption (20 472 C g-1) compared to two heavy metal salts (14 260 C g-1 for Pb2+ and 6265 C g-1 for Cd2+), which is most likely to be due to the ease of mass transfer of lighter Na+ and Cl- ions; When compared, Pb2+ ions tend to show more electrosorption on these fibers than Cd2+ ions. Also, the C-rGOMnPAN electrode system is shown to work with 95% regeneration efficiency when 100 ppm NaCl is used as the electrolyte. Hence, it is clear that the novel binder-free, electrospun C-rGOMnPAN electrodes have the potential to be used in salt removal and also for the heavy metal removal applications of water purification.
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Propensity of a textile material to evaporate moisture from its surface, commonly referred to as the 'moisture management' ability, is an important characteristic that dictates the applicability of a given textile material in the activewear garment industry. Here, an infrared absorbing nanoparticle impregnated self-heating (IRANISH) fabric is developed by impregnating tin-doped indium oxide (ITO) nanoparticles into a polyester fabric through a facile high-pressure dyeing approach. It is observed that under simulated solar radiation, the impregnated ITO nanoparticles can absorb IR radiation, which is effectively transferred as thermal energy to any moisture present on the fabric. This transfer of thermal energy facilitates the enhanced evaporation of moisture from the IRANISH fabric surface and as per experimental findings, a 54 ± 9% increase in the intrinsic drying rate is observed for IRANISH fabrics compared with control polyester fabrics that are treated under identical conditions, but in the absence of nanoparticles. Approach developed here for improved moisture management via the incorporation of IR absorbing nanomaterials into a textile material is novel, facile, efficient and applicable at any stage of garment manufacture. Hence, it allows us to effectively overcome the limitations faced by existing yarn-level and structural strategies for improved moisture management.
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This work reports the fabrication of nanomagnetite- and nanotitania-incorporated polyacrylonitrile nanofibers (MTPANs) by an electrospinning process, which has the potential to be used as a membrane material for the selective removal of Cd(II) and As(V) in water. The fiber morphology was characterized by scanning electron microscopy (SEM). The incorporation of nanomagnetite and nanotitania in the composite fiber matrix was confirmed by energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and Fourier transform infrared (FT-IR) spectroscopy. The fibers doped with nanomagnetite and nanotitania (MPAN and TPAN fibers, respectively), as well as MTPAN and neat polycrylonitrile (PAN) fibers, after thermally stabilizing at 275 °C in air, were assessed for their comparative As(V)- and Cd(II)-ion removal capacities. The isotherm studies indicated that the highest adsorption of Cd(II) was shown by MTPAN, following the Langmuir model with a q m of 51.5 mg/m2. On the other hand, MPAN showed the highest As(V)adsorption capacity, following the Freundlich model with a K F of 0.49. The mechanism of adsorption of both Cd(II) and As(V) by fibers was found to be electrostatically driven, which was confirmed by correlating the point of zero charges (PZC) exhibited by fibers with the pH of maximum ion adsorptions. The As(V) adsorption on MPAN occurs by an inner-sphere mechanism, whereas Cd(II) adsorption on MTPAN is via both surface complexation and an As(V)-assisted inner-sphere mechanism. Even though the presence of coexistent cations, Ca(II) and Mg(II), has been shown to affect the Cd(II) removal by MTPAN, the MTPAN structure shows >50% removal efficiency even for minute concentrations (0.5 ppm) of Cd(II) in the presence of high common ion concentrations (10 ppm). Therefore, the novel polyacrylonitrile-based nanofiber material has the potential to be used in polymeric filter materials used in water purification to remove As(V) and Cd(II) simultaneously.
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The growing demand for water purification provided the initial momentum to produce lanthanide-incorporated nano-hydroxyapatite (HAP) such as HAP·CeO2, HAP·CeO2·La(OH)3 (2:1), and HAP·CeO2·La(OH)3 (3:2). These materials open avenues to remove fluoride and lead ions from contaminated water bodies effectively. Composites of HAP containing CeO2 and La(OH)3 were prepared using in situ wet precipitation of HAP, followed by the addition of Ce(SO4)2 and La(NO3)3 into the same reaction mixture. The resultant solids were tested for the removal of fluoride and lead ions from contaminated water. It was found that the composite HAP·CeO2 shows fluoride and lead ion removal capacities of 185 and 416 mg/g, respectively. The fluoride removal capacity of the composite was improved when La(OH)3 was incorporated and it was observed that the composite HAP·CeO2·La(OH)3 (3:2) has the highest recorded fluoride removal capacity of 625 mg/g. The materials were characterized using scanning electron microscopy-energy-dispersive X-ray (SEM-EDX) spectrometry, Fourier transform infrared (FT-IR) spectrometry, X-ray powder diffractometry (XRD), X-ray photoelectron spectroscopy (XPS), and Brunauer-Emmett-Teller (BET) surface area analysis. Analysis of results showed that Ce and La are incorporated in the HAP matrix. Results of kinetic and leaching analyses indicated a chemisorptive behavior during fluoride and lead ion adsorption by the composites; meanwhile, the thermodynamic profile shows a high degree of feasibility for fluoride and lead adsorption.
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In Brazil, American visceral leishmaniasis (AVL) has become a public health concern due to its high incidence and lethality. This study aimed to analyze the clinical, epidemiological, and laboratory aspects of AVL in a state of Brazil. This descriptive, cross-sectional, retrospective, and quantitative study of notified cases of AVL was carried out in Alagoas between 2008 and 2017 from data obtained from DATASUS/SINAN. Sociodemographic, clinical, and laboratory variables were analyzed. A descriptive analysis was performed using absolute values ââand valid percentages, using tables and/or graphs. Data processing was performed using Stata 12.0®. Results with P <0.05 were considered statistically significant. During the study period, 352 cases of AVL were reported, of which 6.82% died and 38.92% had met a cure criterion. Male patients were predominant (66.76%). Of the total infected patients, 16.76% had attended only the 1st to the 4th grades, with those most affected aged 1 to 4 years (28.69%). Laboratory diagnostic criteria were most commonly used to confirm the notified cases (76.42%), whereas 51.70% and 8.52% of the cases had positive parasitological and immunofluorescence diagnoses, respectively. Finally, the study showed a higher prevalence of the disease in children, men and in rural residents. Although with low lethality, the expressive frequency of AVL in the State of Alagoas was still verified, since there was an increase in the number of cases during the years of the study.
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Leishmaniose Visceral , Brasil/epidemiologia , Criança , Estudos Transversais , Humanos , Laboratórios , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/epidemiologia , Masculino , Estudos Retrospectivos , Estados UnidosRESUMO
Viral hepatitis are widely spread infectious diseases caused by a variety of etiological agents that displays liver tropism as a common characteristic. A descriptive, cross-sectional, observational and retrospective study was conducted through the analysis of viral hepatitis medical records treated and diagnosed from 2010 to 2015. The relationship between the variables were made through the chi-square test. 632 viral hepatitis medical records were analyzed. The highest number of cases happened in 2011. Hepatitis A virus (HAV) infection was predominant. The most affected age group was < 20 years and the highest number of cases observed in this age group was related to HAV (p<0.001). The acute clinical form was predominant, with 70.2% of the cases. 92.3% of which corresponded to HAV infection (p<0.001). Most of the cases occurred in the brown race and male gender. Moreover, regarding the probable source/mechanism of infection, the contact with suspicious water/food for hepatitis A cases was highlighted. The sexual form predominated in HBV infection and previous history of blood transfusion in cases of hepatitis C. Most cases were spotted in the mesoregion of Eastern Alagoas, especially in the capital Maceió. It must be observed the importance of knowing the profile of this disease in order to understand its dissemination and thus have subsidies for the creation of actions and strategies to combat the infection.
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Hepatite A , Hepatite Viral Humana , Adulto , Estudos Transversais , Hepatite A/epidemiologia , Hospitais , Humanos , Masculino , Estudos Retrospectivos , Adulto JovemRESUMO
In this study, hydroxyapatite (HAP) nanocomposites were prepared with chitosan (HAP-CTS), carboxymethyl cellulose (HAP-CMC), alginate (HAP-ALG), and gelatin (HAP-GEL) using a simple wet chemical in situ precipitation method. The synthesized materials were characterized using scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, Brunauer-Emmett-Teller surface area analysis, and thermogravimetric analysis. This revealed the successful synthesis of composites with varied morphologies. The adsorption abilities of the materials toward Pb(II), Cd(II), F-, and As(V) were explored, and HAP-CTS was found to have versatile adsorption properties for all of the ions, across a wide range of concentrations and pH values, and in the presence of common ions found in groundwater. Additionally, X-ray photoelectron spectroscopy and energy-dispersive X-ray spectroscopy confirmed the affinity of HAP-CTS toward multi-ion mixture containing all four ions. HAP-CTS was hence engineered into a more user-friendly form, which can be used to form filters through its combination with cotton and granular activated carbon. A gravity filtration study indicates that the powder form of HAP-CTS is the best sorbent, with the highest breakthrough capacity of 3000, 3000, 2600, and 2000 mL/g for Pb(II), Cd(II), As(V), and F-, respectively. Hence, we propose that HAP-CTS could be a versatile sorbent material for use in water purification.