Factores extrínsecos e intrínsecos asociados a poblaciones fúngicas micotoxigénicas de granos de maíz (Zea mays L) almacenados en silos bolsa en Argentina / Extrinsic and intrinsic factors associated with mycotoxigenic fungi populations of maize grains (Zea mays L.) stored in silobags in Argentina

Con el objeto de caracterizar las poblaciones fúngicas, en particular las especies potencialmente micotoxigénicas, que pueden contaminar los granos de maíz almacenados en silos bolsa con un contenido de humedad superior al recomendado como seguro, se evaluaron 270 muestras extraídas al inicio, a los 90 días y al final de un período de almacenamiento de 5 meses. En dichas muestras se cuantificó e identificó la biota fúngica y se determinó la contaminación con fumonisinas y aflatoxinas. Asimismo, se evaluó el efecto de factores extrínsecos (ambiente), intrínsecos (granos) y tecnológicos (ubicación de los granos en el perfil del silo bolsa) sobre las poblaciones totales y micotoxigénicas. El pH de los granos y el nivel de O2 se redujeron significativamente a los 5 meses, mientras que la concentración de CO2 se incrementó en igual período. Los recuentos totales de la micobiota fueron significativamente mayores en los granos ubicados en el estrato superior del silo bolsa. Se identificaron especies micotoxigénicas de Fusarium, Aspergillus, Penicillium y Eurotium. La frecuencia de aislamiento de Fusarium verticillioides se redujo al final del almacenamiento y Aspergillus flavus solo se aisló en el inicio del almacenamiento. Los recuentos de Penicillium spp. y Eurotium spp. se incrementaron al final del almacenamiento. El 100 % de las muestras presentaron contaminación con fumonisinas, con niveles máximos de 5,707 mg/kg, mientras que las aflatoxinas contaminaron el 40 % de las muestras con niveles máximos de 0,0008 mg/kg. Las condiciones ambientales y de sustrato generadas durante el almacenamiento produjeron cambios en la composición de las poblaciones fúngicas y limitaron el desarrollo de hongos micotoxigénicos y la producción de micotoxinas.

In order to determine the behavior of mycotoxin-producing fungal populations linked with silobags stored corn grains with a moisture content greater at the recommended as safe, 270 samples taken in three times (beginning, 90 days, final) over a five month period of storage were evaluated. The fungal biota was quantified and identified and the contamination with fumonisin and aflatoxin was determined. Extrinsic factors (environment), intrinsic factors (grains) and technological factors (location of the grains in the profile of silobag) were taken into account to evaluate the presence and quantity of total and mycotoxigenic fungal populations. The pH of grains and O2 levels were significantly reduced after five months, while CO2 concentration increased in the same period. The total counts of mycobiota were significantly higher in grains located in the top layer of silobag. Mycotoxigenic species of Fusarium, Aspergillus, Penicillium and Eurotium were identified. The frequency of isolation of Fusarium verticillioides decreased at the end of storage and Aspergillus flavus was isolated only at the beginning of storage. The counts of the Penicillium spp. and Eurotium spp. were increased at the end of storage. Fumonisin contamination was found in all the samples (100 %) with maximum levels of 5.707 mg/kg whereas aflatoxin contaminated only 40 % with maximum levels of 0.0008 mg/kg. The environmental and substrate conditions generated during the storage limited the development of mycotoxigenic fungi and mycotoxin production.

Economic and Health Perspectives of Mycotoxins: A Review

Due to their potent toxicity; mycotoxins have attracted worldwide attention over the years and recently; there has been an increasing disquietness on the part of governments; producers; processors; marketers and consumers over the health and economic significance. The diversity in occurrence; structure and chemistry of mycotoxins make their impact more complex to diagnose. Owing to their usual environmental conditions of production in countries with warm and humid climates as well as poor conditions of storage and handling; agricultural commodities are susceptible to fungal colonization and development which can lead to the accumulation of mycotoxins. As part of drying process; agricultural produce are exposed to contamination by ubiquitous mycoflora that grow; develop and produce some toxic metabolites that are harmful to the consumers. Food is already a limited commodity; especially in developing countries of the world and consumers therefore; either as a matter of choice or for the relative cheapness and affordability during periods of scarcity; opt for the over-fresh produce; sometimes not aware of the adverse health implications such foods pose. In the quest to ensure regular and continuous availability of certain perishable farm produce; especially in developing nations; local farmers and traders resort to unscientific and faulty storage conditions to preserve commodities; thereby pre-disposing produce to fungal colonization and mycotoxin production. Thus; commodities such as groundnuts; maize; sorghum; rice; yam; cassava; tiger nut; soyabeans; cotton seeds; fruits; vegetables spices can be contaminated with toxins of fungal origin such as aflatoxins; ochratoxins; fumonisins; patulin; sterigmatocystin; deoxynivalenol; zearalenone and other mycotoxins which pose serious economic and health risks. This review presents some mycotoxins commonly found on agricultural commodities both in temperate and tropic regions of the world. The acute and chronic toxic effects of these toxins in humans and animals are highlighted. Control measures include education of the populace on the risks of exposure to mycotoxins through skin contact; inhalation and ingestion; early harvesting; rapid appropriate drying; sequestration of diseased seeds from sound seeds; sanitation; use of good agronomic practices; insect control; the use of botanicals and synthetics as storage protectants; biological control and detoxification of mycotoxin-contaminated commodities. Probable related health implications are also discussed with a view to creating better public awareness and providing scientific basis for appreciating the challenges; while proactively promoting the development and implementation of policies at mitigating risk factors. Some mycotoxins; their producer fungi and toxic effects are further presented

Parâmetros metabólicos de ovelhas submetidas a dietas contendo aflatoxina e zearalenona com adição de glucomanano modificado / Metabolic parameters of ewes receiving diets containing aflatoxin and zearalenone with addition of modified glucomannan

As micotoxicoses são grandes causadoras de perdas produtivas em ruminantes, sendo aflatoxina (AFLA) e zearalenona (ZEA) as principais micotoxinas encontradas em alimentos conservados. Estas micotoxinas apresentam efeito sobre o metabolismo animal, através da ação anabólica de metabólitos da ZEA, bem como pelas lesões hepáticas causadas pela AFLA. O objetivo deste estudo foi determinar a influência do adsorvente glucomanano modificado sobre parâmetros metabólicos de ovelhas submetidas à dietas contendo AFLA e ZEA. Foram utilizadas 34 fêmeas divididas em 6 grupos (ZEA; ZEA+ADS; AFLA; AFLA+ADS; CONTROLE+ADS; CONTROLE), recebendo 1,0 mg/kg de ZEA, 1,5 mg/kg de AFLA e/ou 2kg/ton de adsorvente. A ZEA diminuiu os níveis séricos de glicose, em relação ao CONTROLE (p<0,05), porém, o adsorvente não influenciou os níveis de glicose, não havendo diferença entre os grupos ZEA e ZEA+ADS. A ZEA aumentou os níveis de AST e GGT em relação ao grupo CONTROLE (p<0,05), sendo que os níveis de AST foram superiores no grupo ZEA (p<0,05), quando comparado ao grupo ZEA+ADS. Ainda, a aflatoxina causou uma redução nos níveis de albumina, em relação aos valores fisiológicos de ovinos. Assim, a partir destes resultados pode-se concluir que a ZEA causou alterações metabólicas em ovinos, bem como o glucomanano modificado foi eficiente em reduzir a possível agressão hepática causada por esta micotoxina, demonstrada pela diminuição nos níveis de AST.

The micotoxicoses are causing great losses of production in ruminants, being aflatoxin (AFLA) and zearalenone (ZEA) the major mycotoxins found in foods preserved. These mycotoxins have effect on the metabolism animal through the anabolic action of metabolites of the ZEA, and the liver injury caused by AFLA. The purpose of this study was to determine the influence of the sorbent modified glucomannan on metabolic parameters of sheep submitted to diets containing AFLA and ZEA. Were used 34 females divided into 6 groups (ZEA; ZEA+ADS; AFLA; AFLA+ADS; CONTROL+ADS; CONTROL), receiving 1.0 mg/kg of ZEA, 1.5 mg/kg of AFLA and/or 2kg/ton of sorbent. The ZEA decreased serum levels of glucose, for the CONTROL (p <0.05), however, the sorbent not influence the levels of glucose, with no difference between groups ZEA and ZEA+ADS. The ZEA increased levels of AST and GGT compared to group CONTROL (p <0.05), whereas the levels of AST were higher in the group ZEA (p <0.05) when compared to the group ZEA+ADS. Still, the aflatoxin caused a reduction in the levels of albumin, for physiological values of sheep. Thus, from these results it was concluded that ZEA caused metabolic alterations in sheep, and the modified glucomannan was effective in reducing the possible liver aggression caused by this mycotoxin, shown by the decrease in the levels of AST.

[Survey of storage wheat contamination to zearalenone producer Fusarium species in East Azarbaidgjan]

Contamination of storage wheat to zearalenone producer molds represents a significant hazard to consumer health and has thus received increasing attention from food safety authorities and legislators. Various species of Fusarium genus are producer of different mycotoxins including zearalenone at certain conditions. These mycotoxins can enter into the human food and animal feed chain and cause premature or early thelarche, gynecomastia, primary and secondary mycotoxicosis in humans and animals. In this survey, contamination of 162 randomly collected wheat samples to zearalenone producer Fusarium was investigated using direct microscopic examination and culturing samples in specific media. From studied 162 collected wheat samples, 160 [99%] samples had fungal contamination. Aspergillus niger, Penicillium Sp, other species of Asergillus [A. Fumigatus, A. Flavous, A. Niveus, A. cchraceus,..] Fusarium Sp, Alternaria Sp, Cladesporium Sp, Gliocladium Sp. and Trichotecium Sp. were the most frequently detected microorganisms respectively. The presence of moulds sue as Aspergillus Sp, Penicillium Sp, Fusarium Sp, Alternaria Sp, Cladesporium Sp, Gliocladium Sp, and Trichotecium Sp. in consumer wheat samples can lead to the presence of harmful mycotoxins and then could result in serious toxicity and illness in humans. As the fungal contamination has a strong influence on the ultimate quality of wheat, wheat end products and food safety, more attention to the quality and safety of wheat and wheat stored places are necessary

Fungal contamination of consumed tea in East Azarbaidjan Province

Information on the fungal contamination of consumer tea is limited and this kind of contamination is important for food and therefore a survey was undertaken to determine the fungal contamination of consumer tea in East Azarbaidjan province. A total of 100 samples were obtained using standard 20 cm collection sond from whole sales and stores in different part of East Azarbaidjan province and examined according standards methods, Samples were cultured in YCFA medium and incubated at 25oC for maximum 3 weeks and a screening survey for positive samples was carried out 73 [73%] out of total 100 samples had fungal contamination more than 104 colony forming units/gram [cfu/g], Aspergillus niger, Penicillium Sp, Fusarium Sp, Asergillus fumigatus, Alternaria Sp, Cladesporium Sp, Mucor Sp, Gliocladium Sp and Trichotecium Sp were the most frequently detected microorganisms throughout the survey respectively. The presence of moulds such as Aspergillus Sp, Penicillium Sp, Fusarium Sp, Alternaria Sp, Cladesporium Sp, Mucor Sp, Gliocladium Sp and Trichotecium Sp in consumer tea can lead to the presence of harmful mycotoxins produced by these moulds and then could result in serious toxicity and illness in humans, As the fungal contamination has a strong influence on the ultimate quality of tea, tea end products and food safety, more attention to the quality and safety of tea are necessary

Histopatologia e imuno-histoquímica de camundongos C57BL/6 infectados por Toxoplasma gondii cepa ME-49 e alimentados com micotoxinas / Histopatology and immunohistochemistry of C57BL/6 mice infected with Toxoplasma gondii ME-49 strain and fed with mycotoxins

A avaliação do curso da infecção por Toxoplasma gondii em camundongos alimentados com micotoxinas, utilizando a histopatologia e imuno-histoquímica, demonstrou a ocorrência de lesões mais acentuadas nos animais infectados e expostos às toxinas. Diferentes quadros de inflamação e necrose encefálica e hepática mostraram que a associação entre parasitismo e a ingestão das micotoxinas causou agravamento nas lesões. A fumonisina B1(FB1, isolada ou associada a outras micotoxinas) foi responsável por alterações celulares como gigantismo nuclear, hipertrofia celular e células atípicas em tecido hepático. A FB1 foi também relacionada com quadros de desmielinização em tecido cerebral. A presença de cistos ou formas livres da cepa ME-49 de T. gondii foi constatada tanto em animais controle quanto nos alimentados com micotoxinas, mostrando que a cepa do parasita, nesta linhagem C57BL/6 de camundongos, apresenta formas características de fase aguda e crônica da infecção.

The course of toxoplasmosis in mice fed with mycotoxins was evaluated by histopatology and immunohistochemistry. The most severe lesions was seen in animals infected by T. gondii and fed on mycotoxins, when they were compered with control animals. Encephalitis, hepatitis, necrosis foci in the brain and liver showed that the association parasite infection and micotoxicosis aggravated the lesions. The fumonisin B1(isolated or in adiccion to others mycotoxins) was responsable for cellular alteration like nuclear enlargement, cellular hypertrophy, and atypical cells in hepatic tissue. This mycotoxin was also related to brain desmyelinization. The presence of cysts or free parasites was observed in control and intoxicated animals. This result showed that ME49 strain of T. gondii, in C57BL/6 mice, can display typical forms of acute and chronic infection.

Intoxicações por plantas e micotoxinas associadas a plantas em bovinos no Rio Grande do Sul: 461 casos / Plant and plant-associated mycotoxins poisoning in cattle in Rio Grande do Sul, Brazil: 461 cases

Foi realizado um levantamento nos arquivos do Laboratório de Patologia Veterinária (LPV) da Universidade Federal de Santa Maria (UFSM) e revisados os laudos de necropsias de bovinos realizadas entre 1990 e 2005. Foram revisados 2.912 casos referentes a necropsias realizadas por membros do LPV ou a materiais de necropsias realizadas por veterinários de campo que enviaram amostras para avaliação histológica no LPV. Em 461 (15,83 por cento) das necropsias, a causa da morte foi atribuída à ingestão de plantas tóxicas. Em ordem decrescente de freqüência, intoxicações pelas seguintes plantas foram diagnosticadas: Senecio spp (56,14 por cento), Pteridium aquilinum (12,06 por cento), Ateleia glazioviana (10,31 por cento), Solanum fastigiatum (5,04 por cento), Baccharis coridifolia (3,29 por cento), Xanthium cavanillesii (3,07 por cento), Senna occidentalis (2,63 por cento), Ramaria flavo-brunnescens (2,41 por cento), Amaranthus spp (2,19 por cento), Vicia villosa (1,54 por cento), Ipomoea batatas, Prunus sellowii e polpa cítrica (0,44 por cento cada), Cestrum parqui, Claviceps paspali, Claviceps purpurea, Brachiaria spp e Lantana sp (0.22 por cento cada). Em um determinado surto o número de bovinos afetados era substancialmente maior que o número de necropsias realizadas. São discutidos os aspectos relacionados à distribuição geográfica, fatores que induziram a ingestão, índices de morbidade, mortalidade e letalidade, sinais clínicos, achados de necropsia e histopatológicos para cada intoxicação. Quando conhecidos, foram incluídos na discussão aspectos relacionados ao princípio ativo e a patogenia da intoxicação.

From 1990 to 2005, tissues from 2,912 cattle necropsies were examined at the Laboratory of Veterinary Pathology (LPV) of the Federal University of Santa Maria (UFSM), Brazil. These tissues came from necropsies performed by faculty members of the LPV or were mailed-in samples from necropsy performed by veterinarian practitioners. In 461 (15.83 percent) of these necropsies the cause of death was attributed to the ingestion of poisonous plants. In decreasing order of frequency poisoning by the following plants were registered: Senecio spp (56.14 percent), Pteridium aquilinum (12.06 percent), Ateleia glazioviana (10.31 percent), Solanum fastigiatum (5.04 percent), Baccharis coridifolia (3.29 percent), Xanthium cavanillesii (3.07 percent), Senna occidentalis (2.63 percent), Ramaria flavo-brunnescens (2.41 percent), Amaranthus spp (2.19 percent), Vicia villosa (1.54 percent), Ipomoea batatas, Prunus sellowii, cytrus pulp (0.44 percent each), Cestrum parqui, Claviceps paspali, Claviceps purpurea, Brachiaria spp and Lantana sp (0.22 percent each). In a given outbreak the number of affected cattle was substantially higher than the number of necropsies performed. The following aspects are discussed for each plant: geographical distribution; factors inducing ingestion; morbidity, mortality and lethality rates, clinical signs, necropsy findings, histopathology. For those plants in which information on the active principle and pathogenesis are available, these aspects are included in the discussion.

Consideraciones técnicas sobre la problemática de las micotoxinas y las micotoxicosis aviares / Technical considerations on the problem of mycotoxins and poultry mycotoxicosis

La contaminación con Micotoxinas puede ocurrir en el cultivo, cosecha, almacenaje, incluso en el alimento producido. Las Micotoxinas son compuestos altamente estables que pueden producir diversos cuadros en animales y en el ser humano. En las aves, las Micotoxinas más importantes son Aflatoxina, Ocratoxina, Toxina T-2, Diacetoxiscirpenol (DAS), Fumoninisina, Citrinina y Ácido Ciclopiazónico. Entre los mecanismos de prevención de la producción de las Micotoxinas —que comienzan con la eliminación o disminución del crecimiento de hongos—, resalta que en el almacenaje se recomienda utilizar inhibidores de hongos, y uso de agentes secuestrantes o absorbentes de Micotoxinas.

Micotoxinas en la Salud Pública / Micotoxins in Public Health

Las micotoxinas constituyen un problema en el ámbito mundial por su alta incidencia y niveles de ocurrencia en los alimentos para humanos y animales. Las condiciones de colonización de los sustratos por hongos micotoxigénicos así como su posterior contaminación con micotoxinas juegan un papel fundamental en las estrategias de vigilancia y control. Entre los principales hongos micotoxigénicos se encuentran los géneros Aspergillus spp., Penicillium spp. y Fusarium spp. Dentro de las familias más importantes de micotoxinas se encuentran: las aflatoxinas, los tricoticenos, la ocratoxina A, las fumonisinas y la zearalenona. Los diferentes mecanismos de acción tóxica de estas micotoxinas constituyen un riesgo para la salud humana y animal constituyéndose en una problemática de salud pública. En Colombia la situación es compleja dada la deficiente investigación al respecto, los estudios realizados en el país han demostrado que la contaminación de alimentos por algunas micotoxinas es significativa y que se deben formular políticas sanitarias para afrontar este limitante. Se discute el riesgo potencial de las micotoxinas para la salud pública, las dificultades en el diagnóstico y la legislación así como las implicaciones en la seguridad e inocuidad alimentaria.

Antioxidative effects of melatonin in protection against renal tubular damage caused by fumonisin [histological, histochemical and electronmicroscopical studies]

Melatonin is the chief secretory product of the pineal gland and has a very potent antioxidant activity. This study was designed to evaluate the effects of the mycotoxin fumonisin on renal tubular damage and protective role of melatonin to reduce this effect. A total of 48 female albino rats weighing [100-140 g] were used in this study. The animals were divided into six groups, each group contained 8 rats. The first group served as control. The animals of the second group were fed ration contaminated with fumonisin [100 mg/kg diet]. The third group of rats were fed ration contaminated with fumonisin [200 mg/ kg diet]. The fourth group was given daily interperitoneal injection of 10 mg/ kg melatonin and fed ration contaminated with fumonism [100 mg/ Kg diet]. The fifth group was given daily interperitoneal injection of 10 mg/kg melatonin and fed ration contaminated with fumonisin [200 mg/kg diet]. The sixth group was given melatonin only at a dose level of 10 mg /kg. The rats were treated for one month Histological effects in kidney were demonstrated in the form of vacuolar degeneration in tubular epithelial cells with degenerated and pyknotic nuclei in animals fed ration contaminated with fumonisin [100 mg/kg diet], markedly degenerated tubules and glomerular degeneration were noticed in group of rats treated with fumonisin [200 mg/kg diet]. Histochemical results showed marked diminution of protein content, mucopolysaccharides and increase in alkaline phosphatase activity. Quantitative DNA image analysis [Leica image] showed that the kidney contained 12.15% aneuploid cells in the group of rats fed fumonisine at dose level of 200 mg/kg diet. No pathological, histochemical or ultrastructural changes could be noticed in rats treated with melatonin only. Ultrastructural changes were observed in animals fed ration contaminated with fumonisin in the form of shrinkage and degeneration of nuclei. The mitochondria were condensed, fragmented and variable in size and shape. The endoplasmic reticulum was fragmented. The treatment of rats with melatonin along with fumonisin resulted in an improvement in histolgical picture as well as histochemical parameters and ultrastructural changes

Desempenho de perus de corte alimentados com níveis crescentes de afloxinas, com ou sem adiçäo de adsorvente / Turkey performance fed with increasing aflatoxins levels, with or without adsorvent inclusion

Este trabalho foi realizado durante o veräo de 1995/1996 com o objetivo de determinar o nível de aflatoxinas (AFL) capaz de causar prejuízos no desempenho de perus de corte criados sob condiçöes ambientais de baixo desafio, bem como avaliar a eficácia da adiçäo de bentonita sódica natural (BSN) como um adsorvente. Foram utilizados 1008 perus de corte, alojados em 84 boxes seguindo um delineamento experimental de blocos casualizados com 14 tratamentos distribuídos em um arranjo fatorial 7 x 2, sendo 7 níveis de adiçäo de AFL (0, 10, 50, 100, 500, 1000 e 2000ppb) e 2 níveis de adiçäo de BSN (0 e 0,5 porcento). Aos 21 dias de idade, as aves alimentadas com as dietas sem adiçäo de BSN mostraram uma reduçäo significativa (P<0,05) no ganho de peso (GP) e no consumo de raçäo (CR) com níveis de AFL iguais ou superiores a 500ppb, enquanto que aves alimentadas com as dietas com 0,5 porcento de BSN mostraram reduçäo significativa (P<0,05) no GP e CR apenas à partir de 1000ppb de AFL. Estes mesmos resultados foram observados aos 40 dias de idade, entretanto aos 70 dias ocorreu uma reduçäo significativa (P<0,05) no GP e CR das aves à partir de 500ppb de AFL, com ou sem adiçäo de BSN, demonstrando um efeito cumulativo desta micotoxina. Em geral, em todos os níveis de adiçäo de AFL que ocorreu reduçäo significativa no GP e CR das aves, esta foi cerca de 15 a 20 porcento menor nos grupos alimentados com 0,5 porcento de BSN. A conversäo alimentar (CA) das aves foi menos afetada pelos níveis de AFL dietéticos, embora tenha existido uma tendência de piora na CA com altos níveis de AFL, em todas as idades. Aflatoxinas tiveram um grande efeito sobre a taxa de mortalidade (porcentagem MOR), sendo que já aos 21 dias a porcentagem MOR verificada nos lotes que receberam 1000 e 2000ppb de AFL, sem BSN, foi de 15,3 e 72,2 porcento, respectivamente. Antes de completar 40 dias de experimento, 100 porcento das aves alimentadas com dietas contendo 2000ppb de AFL, sem e com BSN, morreram. A adiçäo de 0,5 porcento de BSN proporcionaou uma reduçäo média de 35 porcento na porcentagem MOR em comparaçäo aves alimentadas com dietas sem BSN. Com base nos resultados pode ser concluído que AFL säo extremamente deletérias aos perus e que a adiçäo de 0,5 porcento de BSN na raçäo protege particalmente os perus dos efeitos negativos desta micotoxina.

problem of red color defect in raw milk soft cheese in Egypt

Mycological examination of samples representing 337 tins packed with soft cheese "Domiatti" was done for explanation of a red color defect which is characterized by diffuse deep red color over the surfaces of raw milk soft cheese stored for four months at room temperature without any apparent colonial growth. A red color mold growth over Sabouraud dextrose agar could be isolated and identified as Monascus ruber. The suspected mold was inoculated in experimentally manufactured soft cheese and could produce the same defect. Ascospores of Monascus ruber survived pasteurization, but boiling of milk with holding time of 5 minutes destroyed these spores. Effect of storage temperatures and NaCl concentrations to prevent such defect in cheese were studied and discussed. Economical and public health importance of the isolated mold and its pigment as well as control measures for solving the problem have been discussed

Efeito da fosfina sobre a produçäo de aflatoxinas em amendoim armazenado com elevado teor de umidade / Effect of phosphine on aflatoxin production in peanuts stored with high moisture content

Amendoim recém-colhido, descascado, reumedecido até 0,89 de atividade de água (15,6 por cento de teor de umidade em base úmida) foi exposto a 0,0, 0,5, 1,0 e 1,5 mg/l de fosfina durante 3,7 e 14 dias a 30 por cento e aproximadamente 85 por cento de umidade relativa. As concentraçöes de CO2 foram determinadas após cada período de exposiçäo. Análises das aflatoxinas B1 e G1 foram conduzidas inicialmente e após tratamento. Os teores de CO2 obtidos indicaram que a fosfina nas doses de 1,0 e 1,5 mg/l impediu o desenvolvimento fúngico durante todo o período estudado (14 dias), enquanto a concentraçäo de 0,5 mg/l foi eficiente até 7 dias de estocagem. As 3 doses estudadas controlaram a produçäo de aflatoxinas B1 e G1. O período de proteçäo oferecido pelo fumigante no controle do desenvolvimento fúngico e na produçäo dessas micotoxinas foi relacionado com as doses utilizadas

Carcinoma hepatocelular: 1§ parte / Hepatocellular carcinoma: 1st part

O carcinoma hepatocelular (CHC) é uma das lesöes neoplásicas mais comuns, revelando-se em elevadas incidências na Africa e Asia. Sua ocorrência foi mais do que dobrada no Japäo nos últimos anos. Em nosso país, as casuísticas a este respeito säo pequenas; parece no entanto que a incidência é elevada no Espírito Santo. Hepatocarcinogenos naturais, poluentes ambientais, vírus da hepatite B, álcool, radioterapia, metotrexate, tabagismo e outros säo fatores de risco envolvidos no desenvolvimento do CHC