ABSTRACT The objective of this work was to produce and characterize biochar from sugarcane straw, as well as to investigate possible phytotoxic effects on the germination of cotton, maize, and soybean. To this end, the biochar was produced in a double-drum oven and characterized by different techniques. The germination trials were conducted in vitro, with biochar doses varying between 0 and 100 t/ha. The biochar was obtained with a yield of 40%, pH equal to 9.10, electrical conductivity of 2.22 dS/m and specific surface area of 20.3 m2/g. The elemental analysis showed H/C and O/C atomic ratios of 0.41 and 0.21, respectively. The FTIR showed the presence of C=C groups, while SEM/EDS showed a honeycomb porous structure and nutrients such as Mg, K and Ca. The germination test classified the biochar as a phytonutrient for corn and showed no phytotoxicity for soybeans. On the other hand, for cotton, the highest doses (50 and 100 t/ha) caused phytotoxicity. The results of this work meet the global demands for green techniques. Biochar made from sugarcane straw is a promising technology to improve the infertility of poor soils and manage carbon sequestration.

RESUMO O objetivo deste trabalho foi produzir e caracterizar o biocarvão a partir da palha de cana-de-açúcar, bem como investigar possíveis efeitos fitotóxicos às germinações de algodão, milho e soja. Para tanto, o biocarvão foi produzido em forno de duplo tambor e caracterizado por diferentes técnicas. Os ensaios de germinação foram conduzidos in vitro, com doses de biocarvão variando entre 0 e 100 t/ha. O biocarvão foi obtido com rendimento de 40%, pH igual a 9,10, condutividade elétrica de 2,22 dS/m e área superficial específica de 20,3 m2/g. A análise elementar mostrou razões atômicas H/C e O/C de 0,41 e 0,21, respectivamente. A FTIR mostrou a presença de grupos C=C, enquanto a MEV/EDS mostrou estrutura porosa tipo favo de mel e nutrientes, como o Mg, K e Ca. O ensaio de germinação classificou o biocarvão como fitoestimulante para o milho e mostrou ausência de fitotoxicidade para soja. Por outro lado, para o algodão, as doses mais elevadas (50 e 100 t/ha) causaram fitotoxicidade. Os resultados deste trabalho vêm ao encontro das demandas globais por técnicas verdes. O biocarvão feito da palha de cana-de-açúcar é uma tecnologia promissora para melhorar a infertilidade de solos pobres e gerir o sequestro de carbono.

Abstract The objective of this work is to investigate the conversion of spent coffee grounds (SCG) into biochar (BSC) and the ecotoxicological effects of the product obtained. The SCG and BSC were characterized by characterized by different techniques (TGA/DTG, FTIR, XRD, SEM, EDS, and EDXRF). Proton Nuclear Magnetic Resonance (1H NMR) was used to characterize the aqueous extract of BSC. The inhibitory effect on lettuce (Lactuca sativa) germination was investigated. Besides, antimicrobial activity evaluation trials were conducted with Azospirillum brasilense and Trichoderma spp. The results showed that in the BSC production process, the extractives and lignocellulosic components in the SCG were partly decomposed. Tests conducted with microorganisms did not reveal any toxic effect of BSC. However, high phytotoxicity against lettuce was recorded for rate 100 t/ha of BSC. This effect was associated with the presence of carboxylic acids identified by 1H NMR in the BSC extract aqueous.

RESUMO Devido a sua grande importância mundial, a cultura do feijoeiro requer uma produção em grande escala, tornando necessária a utilização de fertilizantes. Dentre eles, a ureia se destaca como um dos mais importantes. No entanto, observam-se perdas significativas do nitrogênio por meio de lixiviação, volatilização e desnitrificação. Para contornar esse problema, vários grupos de pesquisa têm estudado o revestimento de fertilizantes com polímeros, uma vez que, por meio deles, é possível controlar a liberação de nutrientes, bem como a sua disponibilidade no solo. Nesse contexto, o presente trabalho revestiu grânulos de ureia por meio de uma mistura simples de difenilmetano diisocianato e poliol poliéter. Foram produzidos cinco tipos de revestimentos variando as proporções dos reagentes. Todas as amostras foram caracterizadas por espectroscopia de infravermelho e microscopia eletrônica de varredura e foram realizados ensaios in vivo com Phaseolus vulgaris L.. Os espectros de infravermelho confirmaram a polimerização por meio da formação da ligação de uretana. As micrografias evidenciaram um recobrimento com espessura inferior a 30 µm. Os ensaios de liberação controlada da ureia em água mostraram que os revestimentos poliméricos retardam a liberação da ureia em aproximadamente 50 % durante um período de 200 min. Já os ensaios in vivo mostraram que a utilização da ureia com revestimentos nas proporções (em massa) de 60:40 e 50:50 (difenilmetano diisocianato/poliol poliéter) elevaram o teor de massa seca em 52 e 22 %, respectivamente. Com isso, conclui-se que é possível revestir fertilizantes nitrogenados de forma simples com eficiência, otimizando a liberação dos nutrientes no solo e tornando-os mais sustentáveis.

ABSTRACT Due to its great global importance, bean crop requires large-scale production, making necessary the usage of fertilizers. Among them, urea stands out as one of the most important. However, significant losses of nitrogen are constantly observed through leaching, volatilization and denitrification. In order to circumvent this problem, several research groups have studied the coating of fertilizers with polymers, since, through them, it is possible to control the release of nutrients as well as their availability in the soil. In this context, the present work aim son coating urea granules by means of a simple mixture of diphenylmethane diisocyanate and polyol polyether. Five types of coatings have been produced by varying the proportions of the reactants. All samples were characterized by infrared spectroscopy and scanning electron microscopy. In addition, in vivo assays were performed with Phaseolus vulgaris L.. Infrared spectra confirmed the polymerization by formation of the urethane bond. The micrographs showed coating with a thickness of less than 30 μm. Controlled release urea tests in water have shown that the polymer coatings delay release of the urea by approximately 50% over a period of 200 min. The results of the in vivo tests, in turn, showed that the use of urea with coatings in the 60:40 and 50:50 mass proportions (diphenylmethane diisocyanate/polyol polyether) increased the dry mass content in 52 and 22 %, respectively. In this way, it can be concluded that it is possible to coat nitrogen fertilizers simply with efficiency, allowing the release of nutrients into the soil and making it more sustainable.

Com o objetivo de avaliar a eficácia da azitromicina no tratamento da leishmaniose cutânea, foi realizado ensaio comparativo, em Manaus. Foram recrutados 49 pacientes de ambos os sexos, com idades entre 14 e 70 anos que apresentassem úlceras cutâneas com menos de três meses de evolução e que tivessem exame direto positivo para amastigotas de leishmânia. Estes pacientes foram alocados em dois grupos assim: Grupo I (26) recebeu uma dose diária de 500 mg de azitromicina pela via oral durante 20 dias e o Grupo II, recebeu uma dose diária de 20 mg/kg de antimoniato de meglumina por via intramuscular, durante 20 dias. Do grupo da azitromicina, três (12,5%) de 24 pacientes curaram 60, 90 e 120 dias, respectivamente, enquanto, em 21 (87,5%) de 24 houve falha terapêutica. No grupo do antimonial, oito (42,5%) de 19 pacientes curaram como segue: três no dia 30, um no dia 60, um no dia 90 e três no dia 120. Contudo, em 11 (57,9%) de 19 casos, houve falha terapêutica. A azitromicina foi menos eficaz do que o antimonial, embora, a análise da taxa de resposta por intenção de tratamento não mostrou diferença significativa, entre eles. A azitromicina foi melhor tolerada; porém, mostrou-se pouco eficaz no tratamento da leishmaniose cutânea, em Manaus.

A non-randomized controlled clinical trial was carried outin order to evaluate both azithromycin and antimony efficacy in cutaneous leishmaniasis in Manaus, AM, Brazil. Forty nine patients from both genders, aged 14 to 70, with cutaneous ulcers for less than three months and a positive imprint for Leishmania spp. amastigotes were recruited into two groups. Group I (26 patients) received a daily-single oral dose of 500 mg of azithromycin for 20 days and Group II (23 patients) received a daily-single intramuscular dose of 20 mg/kg of meglumine antimony, also for 20 days. Azithromycin cured three of 24 (12.5%) patients on days 60, 90 and 120 respectively whereas therapeutic failure was considered in 21 of 24 (87.5%) cases. In group II, antimony cured eight of 19 (42.1%) cases as follows: three on day 30, one each on day 60 and day 90, and three on day 120. Therapeutic failure occurred in 11 of 19 (57.9%) individuals. The efficacy of antimony for leishmaniasis was better than azithromycin but analysis for the intention-to-treat response rate did not show statistical difference between them. Although azithromycin was better tolerated, it showed a very low efficacy to treat cutaneous leishmaniasis in Manaus.

Para avaliar a eficácia da azitromicina na leishmaniose cutânea, foi realizado ensaio clínico em Manaus, Amazonas, onde o agente etiológico predominante é a Leishmania (Viannia) guyanensis. Incluídos 41 pacientes com lesões de menos de 12 semanas, sem história de tratamento específico nos últimos três meses e com esfregaço positivo para Leishmania sp. Destes, 31 (75,6%) eram masculinos, idade média 30,2 anos. Todos receberam azitromicina 500 mg em dose única oral, diária, por 10 dias. No dia 25º, 16 (39%) pioraram e receberam antimonial pentavalente via intramuscular por 20 dias e, 21 (61%) que apresentaram melhora da lesão ou esta permanecia inalterada no 25º dia, receberam outro ciclo de 10 dias de azitromicina e foram acompanhados mensalmente. Destes, nove (21,9%) apresentaram piora das lesões na avaliação do dia 55 e iniciaram tratamento com antimonial neste dia. Dos 12 que permaneceram no estudo, porque tinham melhorado clinicamente, três optaram por tratamento com antimonial pentavalente no 55º dia e três apresentaram reepitelização completa das lesões nos dias 55º, 65º e 115º. Seis pacientes não retornaram para avaliação final. Análise por tentativa de tratamento foi 22% e cura confirmada em três (7,3%) casos. Estes resultados mostraram que azitromicina tem baixa eficácia para tratar leishmaniose em área onde a Leishmania (Viannia) guyanensis é o agente etiológico predominante.

An open trial to evaluate the azithromycin efficacy in cutaneous leishmaniasis patients was carried out in Manaus (AM), where Leishmania (Viannia) guyanensis is the main etiologic agent. Forty-one patients with skin lesions of less than 12 weeks duration, without specific treatment for the last three months and a positive imprint to Leishmania sp. were included. From these, 31 (75.6%) were male with median age of 30.2. All of them received a daily-single oral dose of 500 mg of azithromycin for ten days. At 25th day, 16 (39%) presented therapeutic failure and received intramuscular pentavalent antimonial, four were considered lost, 21, that had improved or were inaltered received another ten-day series of azithromycin and were monthly followed, but nine (21.9%) of them presented a poor clinical response and switched to intramuscular pentavalent antimonial on day 55. Of the 12 remaining cases evaluated on day 55, despite of clinical improvement, three asked for antimony therapy and 9 (21.9%) continued the follow-up but, only three were cured on 55th, 85th and 115th days, and six did not come back for final evaluation. The intention-treatment overall response rate was 22% and whole cure was seen in three (7.3%) of cases. Thus, azithromycin showed a low efficacy to treat cutaneous leishmaniasis in Manaus.

This report describes the epidemiological and clinical-evolutive characteristics of eight patients with hantavirus pulmonary syndrome (HPS) in Uberaba, Minas Gerais, Brazil. A positive history of contact with rodents was present in 100% of the cases. The time between the onset of symptoms and hospital care was, on average, 3.6 days. All patients showed clinical and laboratory findings suggestive of HPS. Elevated urea and creatinine levels were observed in 6 (75%) cases, PO2 was < 60 mmHg in 100% of the cases, and a chest X-ray demonstrated a bilateral interstitial-alveolar infiltrate. The diagnosis was confirmed by the detection of IgM antibodies against Sin Nombre virus by ELISA. Three patients died as a direct consequence of HPS.