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Immune Response among Patients Exposed to Molds  [PDF]
David A. Edmondson,Christy S. Barrios,Trevor L. Brasel,David C. Straus,Viswanath P. Kurup,Jordan N. Fink
International Journal of Molecular Sciences , 2009, DOI: 10.3390/ijms10125471
Abstract: Macrocyclic trichothecenes, mycotoxins produced by Stachybotrys chartarum, have been implicated in adverse reactions in individuals exposed to mold-contaminated environments. Cellular and humoral immune responses and the presence of trichothecenes were evaluated in patients with mold-related health complaints. Patients underwent history, physical examination, skin prick/puncture tests with mold extracts, immunological evaluations and their sera were analyzed for trichothecenes. T-cell proliferation, macrocyclic trichothecenes, and mold specific IgG and IgA levels were not significantly different than controls; however 70% of the patients had positive skin tests to molds. Thus, IgE mediated or other non-immune mechanisms could be the cause of their symptoms.
Biological control of mycotoxin-producing molds Controle biológico de fungos de armazenamento produtores de micotoxinas
Flávio Henrique Vasconcelos de Medeiros,Samuel Julio Martins,Tiago Domingues Zucchi,Itamar Soares de Melo
Ciência e Agrotecnologia , 2012, DOI: 10.1590/s1413-70542012000500001
Abstract: Mycotoxins are produced by the secondary metabolism of many fungi and can be found in almost 25% of the world's agricultural commodities. These compounds are toxic to humans, animals, and plants and therefore, efforts should be made to avoid mycotoxin contamination in food and feed. Besides, up to 25% of all harvested fruits and vegetables are lost due to storage molds and/or mycotoxin contamination and many methods have been applied to mitigate these issues, but most of them rely on the use of fungicides. Although chemicals are often the first defensive line against mycotoxigenic fungi, the indiscriminate use of fungicides are awakening the public perception due to their noxious effects on the environment and human/animal health. Thus, there is an increasing public pressure for a safer and eco-friendly alternative to control these organisms. In this background, biological control using microbial antagonists such as bacteria, fungi and yeasts have been shown to be a feasible substitute to reduce the use of chemical compounds. Despite of the positive findings using the biocontrol agents only a few products have been registered and are commercially available to control mycotoxin-producing fungi. This review brings about the up-to-date biological control strategies to prevent or reduce harvested commodity damages caused by storage fungi and the contamination of food and feed by mycotoxins. As micotoxinas s o produzidas pelo metabolismo secundário de várias espécies de fungos e podem ser encontradas em quase 25% das commodities agrícolas. Esses compostos s o tóxicos a humanos, animais e plantas e, portanto, esfor os para evitar a contamina o de micotoxinas em alimentos e ra es devem ser feitos. Além disso, até 25% das frutas e legumes em pós-colheita s o perdidos em decorrência do ataque de fungos de armazenamento e/ou contamina es por micotoxinas. Vários métodos têm sido aplicados para mitigar os problemas de micotoxinas, mas a maioria deles se baseia no uso de fungicidas. Embora os produtos químicos sejam, muitas vezes, a primeira estratégia de defesa contra fungos micotoxigênicos, o uso indiscriminado de fungicidas vem despertando a percep o pública, em raz o de seus efeitos nocivos sobre o meio ambiente e à saúde humana/animal. Assim, existe uma crescente press o pública em busca de alternativas mais segura e n o nocivas ao meio ambiente para controlar estes organismos. Nesse contexto, o controle biológico utilizando antagonistas microbianos, tais como bactérias, fungos e leveduras têm mostrado ser um substituto viável para reduzir a utiliza o de p
Geographic Distribution of Environmental Relative Moldiness Index Molds in USA Homes  [PDF]
Stephen Vesper,Jennie Wakefield,Peter Ashley,David Cox,Gary Dewalt,Warren Friedman
Journal of Environmental and Public Health , 2011, DOI: 10.1155/2011/242457
Abstract: Objective. The objective of this study was to quantify and describe the distribution of the 36 molds that make up the Environmental Relative Moldiness Index (ERMI). Materials and Methods. As part of the 2006 American Healthy Homes Survey, settled dust samples were analyzed by mold-specific quantitative PCR (MSQPCR) for the 36 ERMI molds. Each species' geographical distribution pattern was examined individually, followed by partitioning analysis in order to identify spatially meaningful patterns. For mapping, the 36 mold populations were divided into disjoint clusters on the basis of their standardized concentrations, and First Principal Component (FPC) scores were computed. Results and Conclusions. The partitioning analyses failed to uncover a valid partitioning that yielded compact, well-separated partitions with systematic spatial distributions, either on global or local criteria. Disjoint variable clustering resulted in seven mold clusters. The 36 molds and ERMI values themselves were found to be heterogeneously distributed across the United States of America (USA).
Rapid identification of allergenic and pathogenic molds in environmental air by an oligonucleotide array
Wen-Tsung Hung, Shu-Li Su, Lin-Yi Shiu, Tsung C Chang
BMC Infectious Diseases , 2011, DOI: 10.1186/1471-2334-11-91
Abstract: We developed an oligonucleotide array that could accurately identify 21 important airborne fungi (13 genera) that may cause adverse health problems. The method consisted of PCR amplification of the internal transcribed spacer (ITS) regions, hybridization of the PCR products to a panel of oligonucleotide probes immobilized on a nylon membrane, and detection of the hybridization signals with alkaline phosphatase-conjugated antibodies.A collection of 72 target and 66 nontarget reference strains were analyzed by the array. Both the sensitivity and specificity of the array were 100%, and the detection limit was 10 pg of genomic DNA per assay. Furthermore, 70 fungal isolates recovered from air samples were identified by the array and the identification results were confirmed by sequencing of the ITS and D1/D2 domain of the large-subunit RNA gene. The sensitivity and specificity of the array for identification of the air isolates was 100% (26/26) and 97.7% (43/44), respectively.Identification of airborne fungi by the array was cheap and accurate. The current array may contribute to decipher the relationship between airborne fungi and adverse health effect.Fungi are widely distributed in the natural environment. Fungal spores can be easily dispersed into the air and may cause serious health problems. Exposure to fungal spores can cause a wide spectrum of allergenic reactions, such as asthma, and infections in susceptible individuals [1-4]. Asthma prevalence has considerably increased in recent decades such that it is now one of the most common chronic disorders in the world [5-7]. Some severe diseases, such as allergic bronchopulmonary aspergillosis and fungal sinusitis, may be found in susceptible or immunocompromised individuals through mold exposure [8,9]. The predominant genera of airborne fungi causing health concern are Alternaria, Aspergillus, Cladosporium, and Penicillium [4].In order to decipher the relationship between fungi and potential fungal infection, it is i
Spectrophotometric Determination of Malathion in Environmental Samples
N. V. S. Venugopal,B. Sumalatha,Syedabano
Journal of Chemistry , 2012, DOI: 10.1155/2012/390517
Abstract: A simple, rapid, sensitive, and precise spectrophotometric method for the determination of Malathion is described. The method is based on the decomposition of Malathion in the presence of alcoholic KOH. Dimethyldithiophosphate produced is made to react with Ammonium meta vanadate in Nitric acid with the formation of blue color. Acid degradation of too slow to be important under environmental reaction conditions. However, alkaline degradation is too fast to be a pathway in environmental condition. The products of alkaline degradation are temperature dependant. The absorbance maximum was observed at 760 nm. The Beers law is obeyed up to 11 ppm. Interference study was carried for other pesticides.
Spectrophotometric Determination of Kelthane in Environmental Samples  [PDF]
Etesh K. Janghel, Y. Pervez
American Journal of Analytical Chemistry (AJAC) , 2011, DOI: 10.4236/ajac.2011.26083
Abstract: Sensitive spectrophotometric method for determination of kelthane in sub parts per million level is described, which is based on Fujiwara reaction. Kelthane on alkaline hydrolysis gives chloroform, which can be reacted with pyridine to produce red colour. The colour is discharged by addition of glacial acetic acid. Then Benzidine (4,4’-Bianiline) reagent is added due to which a yellowish-red colour is formed which has an absorption maximum at 490nm. Beer’s law is obeyed in the range of 3.3 - 26.0 µg (0.13 - 1.04 ppm) of Kelthane per 25ml of final solution. The molar absorptivity and Sandell’s sensitivity were found to be 4.32 × 105 L?mol–1?cm–1 and 0.022 µg?cm–2 respectively. The method is found to be free from interferences of other organochlorine pesticides and various co-pollutants and can be successfully applied for the determination of kelthane in environmental samples.
Legionella detection from clinical and environmental samples  [cached]
Maria Luisa Ricci
Italian Journal of Public Health , 2004, DOI: 10.2427/6006
Abstract: Several methods are used for diagnosis of legionellosis: culture, urinary antigen detection, serologic tests, PCR etc., characterised by different level of specificity, sensitivity and rapidity. Microbiological diagnosis is an essential tool to for the prompt adoption of an adequate antimicrobial therapy and to understand the real diffusion of legionellosis. Likewise, the environmental samples analysis allows us to know the distribution of the Legionella in the environment and to detect the origin of the infection during an outbreak by comparing clinical and environmental strains.
Developments in Analytical Methods for Detection of Pesticides in Environmental Samples  [PDF]
Rama Bhadekar, Swanandi Pote, Vidya Tale, Bipinraj Nirichan
American Journal of Analytical Chemistry (AJAC) , 2011, DOI: 10.4236/ajac.2011.228118
Abstract: The present review gives a survey of all the published methods along with their advantages and limitations. Traditional methods like thin layer chromatography, gas chromatography, liquid chromatography etc are still in use for this purpose. But some recent bio-analytical methods such as immunosensors, cell based sensors etc. have also gained equal importance. This article also overviews various electro-analytical methods and their applications as detection devices when combined with FIA and biosensors. Lastly nanoparticle based biosensors have also been discussed. The review concludes with futuristic approach to reduce the risks caused by pesticides. This scrutiny should provide concise evaluation of different techniques employed for pesticide detection in environmental samples.
Trace Determination of Palladium in Environmental Samples by Adsorptive Voltammetry
Rojas,C. L.;
Portugaliae Electrochimica Acta , 2005,
Abstract: the objective of the present work is the study and optimization of a voltammetric methodology to determine palladium traces and ultratraces, with the purpose of being able to establish the environmental levels of this element and to verify if a contamination takes place starting from the gases of escape of the vehicles equipped with catalytic converters. the voltammetric determination of palladium is based in the formation of a complex of palladium with dimethylglyoxime that adsorbes actively on the surface of a hanging mercury drop electrode, for then to be reduced when making the square wave potential sweep. the quantification is made by the method of standard additions. the study of interferences demonstrated that na+, mg2+, k+, ca2+, zn2+, cu2+ and al3+ are not even interferences at the level of 10 mg/l. the detection and quantification limits of the methodology are respectively 10 ng/l and 33 ng/l, with a sensibility of (4.3±0.8)*102 na l/ng.
Species-specific Fungal DNA in Airborne Dust as Surrogate for Occupational Mycotoxin Exposure?  [PDF]
Anne Straumfors Halstensen
International Journal of Molecular Sciences , 2008, DOI: 10.3390/ijms9122543
Abstract: Possible health risks associated with occupational inhalation of mycotoxin-containing dust remain largely unknown, partly because methods for mycotoxin detection are not sensitive enough for the small dust masses obtained by personal sampling, which is needed for inhalable exposure measurements. Specific and sensitive PCR detection of fungi with mycotoxin-producing potential seem to be a good surrogate for occupational exposure measurements that include all fungal structures independent of morphology and cultivability. Results should, however, be interpreted with caution due to variable correlations with mycotoxin concentrations.
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