In many settings, the lack of sensitive biomarkers of disseminated histoplasmosis (DH) leads to a clinical reliance on older diagnostic methods and delayed treatment initiation. The early recognition ...of DH is critical for survival, especially in patients with human immunodeficiency virus (HIV). This study aimed to identify clinical and laboratory findings associated with the definitive diagnosis of DH in low-income HIV patients in endemic areas.
Febrile AIDS patients with suspected DH who were admitted to a reference hospital in northeastern Brazil from January 2006 to January 2007 were evaluated for clinical and laboratory findings associated with DH diagnosis.
One hundred seventeen patients with fever were included, and 48 (41%) cases of DH were determined by Histoplasma capsulatum identification. A higher fever (≥38.5ºC), maculopapular/papular rash, splenomegaly, hepatomegaly, wheezing, hemoglobin ≤9.5g/dL, platelets ≤80,000/µL, CD4 count ≤75/µL, aspartate aminotransferase (AST) level ≥2.5 times the upper limit of normal (ULN), lactate dehydrogenase (LDH) ≥5times the ULN; and international normalized ratio (INR) >2 times the ULN were significantly associated with DH. A multivariable analysis identified hepatomegaly adjusted (a) prevalence ratio (PR)= 1.96; 95% confidence interval (CI): 1.21-3.16), CD4 count ≤75/µL (aPR = 2.02; 95% CI: 1.06-3.83), LDH ≥5 times the ULN (aPR = 2.23; 95% CI: 1.44-3.48), and maculopapular/papular rash (aPR = 1.70; 95% CI: 1.02-2.83) were independent risk factors for DH.
These easily assessed parameters can facilitate clinical decision-making for febrile AIDS patients with suspected DH in low socioeconomic and Histoplasma-endemic regions.
Ionic liquids are a class of fluids that requires the attentions of experimentalist and theoreticians. In a new project on synthesis and characterization of new and not-so-new ionic liquids, the ...study of several thermophysical properties of these liquids was started, namely binary diffusion, electrical conductivity, heat capacity, surface tension, viscosity and thermal conductivity. Among others we will study 1-
n-butyl-3-methyl-imidazolium bis(trifluoromethanesulfonyl)imide, (C
4mimNTf
2), 1-
n-butyl-3-methyl-imidazolium dicyanamide, (C
4mimdca), 1-ethyl-3-methyl-imidazolium ethylsulfate, (C
2mimEtOSO
3) and methyltrialkylammonium dicyanamide Aliquat
®336-deriveddca, and in the case of diffusion, their mixtures with water.
It is the purpose of this paper to report data on the density, using vibrating tube densimetry, infinite dilution diffusion coefficients, using the Taylor dispersion method, heat capacity, using DSC equipment and surface tension, using the Wilhelmy plate method. Density measurements were performed at atmospheric pressure between 293 and 363
K and several isotherms, depending on the stability of the compound, up to 60
MPa, with an uncertainty of 0.4%. Measurements were performed at 298.03
K for the infinite dilution measurements, with an uncertainty of 1.3–3.5%, for temperatures between 300 and 370
K for heat capacity, with an uncertainty better than 1.5%, and between 292 and 395
K for surface tension, with an uncertainty of 1.5–1.8%.
A brief analysis of the potential of the fluids studied as engineering heat transfer fluids, namely its heat storage capacity was also performed.
In this work, three composites with different contents (5, 10, and 15% w/w) of kraft pulp fibre were produced as reinforcing elements for natural latex matrix and the mechanical properties were ...evaluated. In order to improve the interfacial adhesion between the matrix and the reinforcing element, chemical modifications were carried out on the surface of the fibres using octanoyl and benzoyl chlorides as modifying agents. The extension of chemical modification of the fibres was visualized by the presence of absorption bands in the spectroscopy analyzes of the modified fibre in relation to the crude fibre (ester carbonyl 1700–1740 cm
−1
); in addition, the hydroxyl band was preserved, which indicates a modification of surface character. The modified fibres became more hydrophobic due to the decrease in surface energy and the change in the dispersive and polar components. An increase in the storage modulus was observed for the composites with surface-modified fibres, which agrees with the improved dispersion between the surface-modified fibres and the matrix verified by means of scanning electron microscopy images. The incorporation of fibres did not cause changes in the thermal properties of the composites.
Heterogeneous catalysis for biodiesel production via esterification has emerged as a preferred route as it permits to overcome the disadvantages associated to homogeneous catalysis, which presents ...serious drawbacks that affect biodiesel production and increase its costs such as corrosivity, difficult removal, and non-reuse of the catalyst. This study evaluated the esterification of oleic acid (OA) using CoFe
2
O
4
and MnFe
2
O
4
ferrite magnetic nanoparticles (MNPs) coated with sulfonated lignin (SL). SL was synthesized from sugarcane bagasse lignin employing acetyl sulfate (sulfonating agent). Two different proportions of reactants were adopted, obtaining the solids SL5 and SL7.5—posteriorly incorporated into the MNPs. Reaction parameters evaluated were as follows: time (4 and 6 h) and temperature (80 and 100 °C), with other parameters fixed. The catalysts were characterized by XRD, BET method, SEM, TGA, and elemental analysis. The sulfonic group contents were determined by acid–base titration. The conversion of OA into methyl esters was determined by GC–MS and FTIR. Elemental analysis showed that SL5 and SL7.5 have 2.68% of sulfur content by mass and the following minimal molecular formulas C
9
H
10,52
O
5,62
(SO
3
H)
0,18
and C
9
H
10,52
O
5,62
(SO
3
H)
0,17
. XRD and TGA data evidenced that coated MNPs exhibit incorporation percentage of SL higher than 50%, with the best results for CoFe
2
O
4
-SL5 (79.5%) and CoFe
2
O
4
-SL7.5 (78.5%). GC–MS and FTIR data revealed that the highest OA conversions were achieved under 6 h and 100 °C. In addition, CoFe
2
O
4
-SL5 and MnFe
2
O
4
-SL7.5 exhibited the best catalytic performances in the esterification reactions with conversions of OA into fatty acid methyl esters of approximately 80%.
Graphical abstract
•Biodiesel from sunflower oil was successfully purified with natural adsorbents.•Starch from different sources and cellulose fibers were used as adsorbents.•Dry washing has removed more impurities ...than the wet washing.•Was reduced the acidity index, alkalinity, free glycerine and turbidity of biodiesel.
This work describes a study of the purification of biodiesel produced from sunflower oil by dry cold washing using natural adsorbents as cellulose and starch from different sources (corn, potato, cassava and rice), and the comparison with dry cold washing with a commercial adsorbent Select 450® and with the conventional wet washing with hot water. The purification by dry washing was carried out by varying the amount of adsorbents in 1%, 2%, 5% and 10% (w/v) at 25°C for 10min. For the purification by wet washing, the biodiesel was successively washed with acidified water and pure water at 85°C until neutralisation. The efficiency of the processes for the removal of biodiesel impurities was evaluated by determining the acidity index, combined alkalinity, free glycerine and turbidity of the biodiesel. All adsorbents studied presented good efficiency in the removal of the impurities and showed similar behaviour independent of the kind or amount of adsorbent employed. The use of natural adsorbents for the purification of biodiesel have been shown to be a promissory process to be applied as an industrial stage of the purification of biodiesel during their production.
RESUMO O presente estudo contempla a aplicação de nanopartículas magnéticas de ferrita de manganês MnFe2O4 (NPM) modificadas com poliestireno sulfonado (PSS) na adsorção de íons de Pb (II) para fins ...de tratamento de água contaminada. A funcionalização da nanopartícula com o polímero objetivou aumentar a capacidade de adsorção e incluir a utilização de material reciclável em função da importância ambiental. Os adsorventes foram caracterizados por espectroscopia no infravermelho por transformada de Fourier, espectroscopia de energia dispersiva por raio X, difração de raios X, microscopia eletrônica de varredura, microscopia de força atômica, análise elementar, análise termogravimétrica, ponto de carga zero, área superficial e porosidade. O PSS representou 14% da massa das nanopartículas magnéticas de MnFe2O4 funcionalizadas com o poliestireno sulfonado (NPM-PSS) e o teor de grupos sulfônicos foi de 17,18%. Os modelos de isoterma de Freundlich e cinético de pseudossegunda ordem apresentaram maior acurácia pelos dados experimentais de adsorção dos íons Pb (II) pela NPM-PSS, cuja capacidade de adsorção das nanopartículas variou de 6,254 a 7,535 mg g−1.
ABSTRACT The present study contemplates the application of magnetic nanoparticles of manganese ferrite MnFe2O4 (NPM) modified with sulfonated polystyrene (PSS) in the adsorption of Pb(II) ions for the purpose of treating wastewater. The functionalization of the nanoparticle with the polymer aimed to increase the adsorption capacity and include the use of recyclable material due to its environmental importance. Adsorbents were characterized by Fourier transform infrared spectroscopy, energy dispersive X-ray spectroscopy, X-ray diffraction, scanning electron microscopy, atomic force microscopy, elemental analysis, thermogravimetric analysis, point of zero charge, surface area, and porosity. PSS represented around 14% of the mass of magnetic nanoparticles of MnFe2O4 functionalized with sulfonated polystyrene (NPM-PSS) and the content of sulfonic groups was 17.18%. The Freundlich isotherm and pseudo second order kinetic models showed greater accuracy by the experimental data of adsorption of Pb (II) ions by NPM-PSS, whose adsorption capacity of nanoparticles ranged from 6.254 to 7.535 mg g−1.
Staphylococcus aureus is a pathogen widely involved in wound infection due to its ability to release several virulence factors that impair the skin healing process, as well as its mechanism of drug ...resistance. Herein, sodium alginate and chitosan were combined to produce a hydrogel for topical delivery of neomycin to combat S. aureus associated with skin complications. The hydrogel was formulated by combining sodium alginate (50 mg/mL) and chitosan (50 mg/mL) solutions in a ratio of 9:1 (HBase). Neomycin was added to HBase to achieve a concentration of 0.4 mg/mL (HNeo). The incorporation of neomycin into the product was confirmed by scanning electron microscopy, FTIR and TGA analysis. The hydrogels produced are homogeneous, have a high swelling capacity, and show biocompatibility using erythrocytes and fibroblasts as models. The formulations showed physicochemical and pharmacological stability for 60 days at 4 ± 2 °C. HNeo totally inhibited the growth of S. aureus after 4 h. The antimicrobial effects were confirmed using ex vivo (porcine skin) and in vivo (murine) wound infection models. Furthermore, the HNeo-treated mice showed lower severity scores than those treated with HBase. Taken together, the obtained results present a new low-cost bioproduct with promising applications in treating infected wounds.
•Hydrogels were produced based on the electrostatic interaction between alginate-chitosan.•The addition of neomycin confers antimicrobial effects on the hydrogel.•Hydrogels are biocompatible, porous and absorbent.•Neomycin hydrogel improves inflammation in infected wounds.•Hydrogels reduce Staphylococcus aureus burden in wounds.
A permanente cobertura vegetal do solo, em Florestas de Araucária, contribui na conservação de sua biodiversidade edáfica. O objetivo deste trabalho foi avaliar o potencial da fauna edáfica e das ...variáveis ambientais explicativas (físico-químicas e microbiológicas do solo) na discriminação de florestas com araucária nativa e reflorestada. Avaliaram-se florestas com Araucaria angustifolia nativa (NF) e reflorestada (RF) em três regiões distintas no estado de São Paulo, representando três repetições. Em cada área, 15 amostras de solo foram coletadas para avaliação dos atributos físicos, químicos e microbiológicos e, nos mesmos pontos, procedeu-se às coletas da fauna utilizando-se o método de armadilhas de queda (Pitfall traps). A fauna do solo foi influenciada pela sazonalidade, apresentando maior abundância de indivíduos no verão. Os grupos Collembola, Formicidae e Coleoptera foram os mais abundantes, independentemente da época de amostragem e tipo de floresta. A Análise de Componentes Principais (ACP) e Análise Canônica Discriminante (ACD) claramente diferenciaram as áreas de araucárias. Na ACP, Hemiptera, Collembola e Diplopoda ficaram associados à RF no inverno, principalmente pelos maiores valores de matéria seca da serapilheira. Já em NF, foram os grupos Orthoptera, Hymenoptera, Araneae e Coleoptera, explicados pela melhor qualidade do solo e da serapilheira. No verão, ficaram associados à NF, os grupos Formicidae, Hemiptera, Orthoptera, Araneae, Coleoptera e Collembola, explicados pelos maiores valores de CBM, Ca, P, C-org, macroporosidade e atividade de desidrogenase. Na ACD, a abundância de grupos taxonômicos foi o atributo da fauna edáfica mais importante para a discriminação das florestas. Da mesma forma, a umidade do solo, teor de P no solo, porosidade total e teor de S na serapilheira contribuíram na discriminação das florestas. A semelhança entre as áreas, em relação aos grupos da fauna edáfica, indica que está ocorrendo uma estabilidade das áreas reflorestadas comparável às nativas.
IntroductionCOVID-19 may lead to persistent and potentially incapacitating clinical manifestations (post-acute sequelae of SARS-CoV-2 infection (PASC)). Using easy-to-apply questionnaires and scales ...(often by telephone interviewing), several studies evaluated samples of COVID-19 inpatients from 4 weeks to several months after discharge. However, studies conducting systematic multidisciplinary assessments of PASC manifestations are scarce, with thorough in-person objective evaluations restricted to modestly sized subsamples presenting greatest disease severity.Methods and analysesWe will conduct a prospective observational study of surviving individuals (above 18 years of age) from a cohort of over 3000 subjects with laboratory-confirmed COVID-19 who were treated as inpatients at the largest academic health centre in Sao Paulo, Brazil (Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo). All eligible subjects will be consecutively invited to undergo a 1–2-day series of multidisciplinary assessments at 2 time-points, respectively, at 6–9 months and 12–15 months after discharge. Assessment schedules will include detailed multidomain questionnaires applied by medical research staff, self-report scales, objective evaluations of cardiopulmonary functioning, physical functionality and olfactory status, standardised neurological, psychiatric and cognitive examinations, as well as diagnostic laboratory, muscle ultrasound and chest imaging exams. Remaining material from blood tests will be incorporated by a local biobank for use in future investigations on inflammatory markers, genomics, transcriptomics, peptidomics and metabolomics.Ethics and disseminationAll components of this programme have been approved by local research ethics committees. We aim to provide insights into the frequency and severity of chronic/post-COVID multiorgan symptoms, as well as their interrelationships and associations with acute disease features, sociodemographic variables and environmental exposures. Findings will be disseminated in peer-reviewed journals and at scientific meetings. Additionally, we aim to provide a data repository to allow future pathophysiological investigations relating clinical PASC features to biomarker data extracted from blood samples.Trial registration numberRBR-8z7v5wc; Pre-results.
Low-cost lignocellulosic filters were made from soybean hulls (SH), sugarcane bagasse fibers (SBF), cellulose nanofibers (CNF), and Kraft-bleached pulp (BP) as renewable feedstocks and applied in Cu ...(II) and Cd (II) removal from aqueous medium. Filtration was performed with a vacuum pump; filtration times ranged from 3 to 1200 seconds. For the same filter, the best permeate flow was 13,333 L.h.m-2 for both cations. The best Cd (II) removal (77.2 %) was achieved within 7 seconds at a permeate flow of 5,714 L.h.m-2. The same filter was also the best at removing Cu (II) (46.5 %), which was achieved within 7 seconds at a permeate flow of 5,714 L.h.m-2, as well. This short time evidenced that a long contact time is not needed to achieve higher removal. The best filter was made of BP, CNF, and SH. The presence of SBF and SH increased the contact angle and decreased the solid free energy surface. By FTIR-ATR it was possible to verify with which groups present in the chemical structures of the filter components the Cd (II) and Cu (II) cations interacted best. These results demonstrate the potential use of lignocellulosic biomass for producing composites aimed at water decontamination.
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