ABSTRACT
Aflatoxins are carcinogens produced by the fungi Aspergillus flavus and A. parasiticus that contaminate pistachio crops. International markets reject pistachio when aflatoxins exceed permitted maximum levels. Releasing the atoxigenic strain AF36 of A. flavus is the leading aflatoxin pre-harvest control method. The product AF36 Prevail, sorghum grains coated with AF36 propagules, has been used in California since 2017. However, a high percentage of grains of the Prevail fail to sporulate in orchards. Here, the effect of soil moisture on the percentage of AF36 product grains sporulating (SG) and the quantity of spores per grain using a sporulation index (SI) was determined. Under controlled conditions, SG was higher than 85% when soil moisture was 13% or more, and SI increased with increasing soil moisture from 8.4 to 21%. The highest AF36 sporulation occurred near the micro-sprinklers when the grains were not impacted by the irrigation water drops. Arthropod predation was responsible for lost product grains, which was more pronounced in non-tilled soil than in tilled soil. Dispersal of the AF36 spores decreased markedly with the height and distance from the inoculum source, following a pattern of diffusion equations. However, AF36 spores easily reached canopies of pistachios located 10 m from the inoculum source. Our results indicate that AF36 Prevail should be applied close to the irrigation line in the moist soil area but avoiding the areas where excess irrigation causes water accumulation. The biocontrol of aflatoxins in California's pistachio production areas was optimized by improving the field realization of the biological control agent.
ABSTRACT
Ochratoxin A (OTA) is a potent mycotoxin produced by Aspergillus and Penicillium spp., which contaminates many crops, including pistachios. Pistachios contaminated with OTA may be subjected to border rejections resulting in significant economic losses to the United States agricultural revenues. The current study examined prevalence of OTA in California-grown pistachios and identified its causal agents. OTA was detected in 20% of samples from 2018 to 2021 (n = 809), with 18% of samples exceeding the European Union regulatory limit of 5 µg/kg. Fungi potentially responsible for OTA contamination were isolated from leaves, nuts, and soil collected from 14 pistachio orchards across California. A total of 1,882 isolates of Aspergillus section Nigri and 85 isolates of section Circumdati were recovered. Within section Nigri, 216 (11.5%) isolates were identified as potential OTA producers using a boscalid-resistance assay. Phylogenetic analyses of partial gene sequences for ß-tubulin and calmodulin genes resolved section Circumdati into four species: A. ochraceus (33%), A. melleus (28%), A. bridgeri (21%), and A. westerdijkiae (19%). A. westerdijkiae produced the highest levels of OTA in inoculated pistachios (47 µg/g), followed by A. ochraceus (9.6 µg/g) and A. melleus (3.3 µg/g). A. bridgeri did not produce OTA. OTA production by section Circumdati was optimal from 20 to 30°C. All 216 boscalid-resistant isolates from section Nigri were identified as A. tubingensis, and representative isolates (n = 130) produced 3.8 µg/kg OTA in inoculated pistachios. This is the first detailed report on OTA contamination and causal fungi in California pistachios and will be helpful in devising effective management strategies.
Subject(s)
Ochratoxins , Penicillium , Pistacia , Ochratoxins/analysis , Pistacia/microbiology , Pistacia/chemistry , California , Penicillium/genetics , Penicillium/isolation & purification , Phylogeny , Aspergillus/genetics , Aspergillus/isolation & purification , Aspergillus/metabolism , Food Contamination/analysis , Plant Diseases/microbiologyABSTRACT
ABSTRACT A 5-year-old child, weighing 15 kg, with three previous sternotomies, presented with right heart failure due to severe stenosis and regurgitation of the bioprosthetic tricuspid valve. A percutaneous tricuspid valve-in-valve procedure with an Edwards S3 valve was ofered for compassionate use, performed with no complications and with a significant clinical condition improvement.
ABSTRACT
A 5-year-old child, weighing 15 kg, with three previous sternotomies, presented with right heart failure due to severe stenosis and regurgitation of the bioprosthetic tricuspid valve. A percutaneous tricuspid valve-in-valve procedure with an Edwards S3 valve was ofered for compassionate use, performed with no complications and with a significant clinical condition improvement.
Subject(s)
Heart Valve Prosthesis Implantation , Heart Valve Prosthesis , Tricuspid Valve , Child, Preschool , Humans , Bioprosthesis , Cardiac Catheterization/methods , Heart Valve Prosthesis Implantation/methods , Latin America , Prosthesis Design , Prosthesis Failure , Treatment Outcome , Tricuspid Valve/surgeryABSTRACT
The species Aspergillus flavus and A. parasiticus are commonly found in the soils of nut-growing areas in California. Several isolates can produce aflatoxins that occasionally contaminate nut kernels, conditioning their sale. Strain AF36 of A. flavus, which does not produce aflatoxins, is registered as a biocontrol agent for use in almond, pistachio, and fig crops in California. After application in orchards, AF36 displaces aflatoxin-producing Aspergillus spp. and thus reduces aflatoxin contamination. Vegetative compatibility assays (VCAs) have traditionally been used to track AF36 in soils and crops where it has been applied. However, VCAs are labor intensive and time consuming. Here, we developed a quantitative real-time PCR (qPCR) protocol to quantify proportions of AF36 accurately and efficiently in different substrates. Specific primers to target AF36 and toxigenic strains of A. flavus and A. parasiticus were designed based on the sequence of aflC, a gene essential for aflatoxin biosynthesis. Standard curves were generated to calculate proportions of AF36 based on threshold cycle values. Verification assays using pure DNA and conidial suspension mixtures demonstrated a significant relationship by regression analysis between known and qPCR-measured AF36 proportions in DNA (R2 = 0.974; P < 0.001) and conidia mixtures (R2 = 0.950; P < 0.001). Tests conducted by qPCR in pistachio leaves, nuts, and soil samples demonstrated the usefulness of the qPCR method to precisely quantify proportions of AF36 in diverse substrates, ensuring important time and cost savings. The outputs of this study will serve to design better aflatoxin management strategies for pistachio and other crops.
Subject(s)
Aflatoxins , Pistacia , Aflatoxins/analysis , Aspergillus flavus/genetics , Nuts , Plant Leaves/chemistry , Real-Time Polymerase Chain Reaction , SoilABSTRACT
BACKGROUND: Patients with end-stage heart failure, suffering from severe pulmonary hypertension (PH) and elevated pulmonary vascular resistance, are not eligible for heart transplant due to high mortality risk and primary graft dysfunction. Severe PH may be favoured by functional severe mitral regurgitation, which is present in many cardiopathies like end-stage Chagasic cardiomyopathy. CASE SUMMARY: We present a case of a young man with end-stage heart failure secondary to Chagas cardiomyopathy with severe functional mitral regurgitation (FMR) and severe PH. The patient received percutaneous correction with MitraClip® system reducing PH and making him a suitable candidate for heart transplant. DISCUSSION: In patients with advanced heart failure, FMR, and severe PH, optimal treatment according to current guide lines is recommended. MitraClip® therapy appears to be safe and effective for control of severe PH as a bridge measure for cardiac transplantation.
ABSTRACT
Se presenta el caso de un varón de 26 años que experimenta clínica compatible con trastorno perceptivo persistente por alucinógenos tras la ingesta de una feniletilamina, la 4-bromo-2,5-dimetoxifeniletilamina, conocida también como Nexus, Bromo, Erox, Venus o Afro. El consumo de esta sustancia ha ido adquiriendo popularidad en España en el contexto de fiestas rave y como droga de club (AU)
We are presenting a case-report of a 26 years old man who experienced symptoms compatible with hallucinogen persisting perception disorder after the ingestion of a phenylethylamine, the 4-bromo-2,5-dimethoxyphenethylamine, also known as Nexus, Bromo, Erox, Venus or Afro. The use of this substance has gained popularity in Spain in the context of rave parties and as club drug (AU)
Subject(s)
Adult , Humans , Male , Hallucinogens/pharmacokinetics , Perceptual Disorders/chemically induced , Depersonalization/chemically induced , Substance-Related Disorders/diagnosisABSTRACT
Aflatoxins, highly toxic carcinogens produced by several members of Aspergillus section Flavi, contaminate crops in temperate zones. In the state of Sonora, Mexico, maize is cultivated from 0 to 2100 masl with diverse cultivation practices. This is typical of the nation. In order to design better sampling strategies across Mexico, aflatoxin-producing fungal communities associated with maize production during 2006, 2007, and 2008 in Sonora were investigated in four agro-ecological zones (AEZ) at varying elevation. Fungal communities were dominated by the Aspergillus flavus L strain morphotype (46%), but variation occurred between years and among AEZ. Several atoxigenic isolates with potential to be used as biocontrol agents for aflatoxin mitigation were detected in all AEZ. The characteristics of each AEZ had minimal influences on fungal community structure and should not be a major consideration for future sampling designs for Mexico. Insights into the dynamics and stability of aflatoxin-producing fungal communities across AEZ are discussed.
Subject(s)
Aflatoxins/metabolism , Fungi/isolation & purification , Fungi/metabolism , Soil Microbiology , Biodiversity , Fungi/classification , Mexico , Zea mays/growth & developmentABSTRACT
Humans and animals are exposed to aflatoxins, toxic carcinogenic fungal metabolites, through consumption of contaminated food and feed. Aspergillus flavus, the primary causal agent of crop aflatoxin contamination, is composed of phenotypically and genotypically diverse vegetative compatibility groups (VCGs). Molecular data suggest that VCGs largely behave as clones with certain VCGs exhibiting niche preference. VCGs vary in aflatoxin-producing ability, ranging from highly aflatoxigenic to atoxigenic. The prevalence of individual VCGs is dictated by competition during growth and reproduction under variable biotic and abiotic conditions. Agronomic practices influence structures and average aflatoxin-producing potentials of A. flavus populations and, as a result, incidences and severities of crop contamination. Application of atoxigenic strains has successfully reduced crop aflatoxin contamination across large areas in the United States. This strategy uses components of the endemic diversity to alter structures of A. flavus populations and improve safety of food, feed, and the overall environment.
Subject(s)
Aflatoxins/toxicity , Aspergillus flavus/classification , Crops, Agricultural/microbiology , Aspergillus flavus/metabolism , Aspergillus flavus/physiology , Genotype , Humans , Phenotype , Species SpecificityABSTRACT
Antecedentes: La mayoría de los cánceres colorrectales se desarrollan en pólipos adenomatosos; su detección y extirpación previene el cáncer colorrectal. Varias características de los adenomas, como: número, tamaño, morfología, variedad histológica y grado de displasia, se han considerado como factores de riesgo para su malignización. Objetivo: Conocer la frecuencia de los adenomas colorrectales los principales factores de riesgo para su malignización. Métodos: Se analizaron retrospectivamente los hallazgos endoscópicos de 846 colonoscopias realizadas en nuestro servicio entre 1989 y 1994, regisrándose los pacientes con pólipos colorrectales, así como las características de los adenomas, para determinar los factores de riesgo para su malignización. Resultados: Se encontraron 183 821.6 por ciento) pacientes con 322 pólipos colorrectales; sólo se estudiaron 214 extirpados por polipectomía transcolonoscópica; 120 (57 por ciento) fueron pólipos neoplásicos, y 94 (43 por ciento) no neoplasicos; entre los neoplásicos, 100 (83.4 por ciento) fueron adenomas tubulares, 11 (9.1 por ciento) adenomas tubulovellosos y 9 (7.5 por ciento) adenomas vellosos. Se encontraron. 16 (7.4 por ciento) adenomas con carcinoma, 14 (87.5 por ciento) de ellos en pacientes mayores de 50 años y en pólipos mayores de 1 cm (p 0.040); 11 (68.7 por ciento) fueron sésiles, con una p 0.001. Conclusiones: Los adenomas tubulares son los pólipos neoplásicos más frecuentes. La edad del paciente, el tamaño y morfología del pólipo, son los factores de riesgo significativamente estadístico para la malignización de los adenomas.
Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Adenoma, Villous/diagnosis , Colonic Diseases , Colonic Neoplasms/etiology , Colonoscopy , Histology , Adenomatous Polyps/diagnosis , Adenomatous Polyps/physiopathology , Adenomatous Polyps/mortality , Colonic Polyps/diagnosis , Colonic Polyps/physiopathology , Colonic Polyps/mortality , Risk FactorsABSTRACT
Los autores presentan un caso de PORFIRIA ERITROPOYETICA CONGENITA, cuadro clínico muy poco frecuente conociéndose apenas referencia de 60 casos publicados en el mundo, siendo el nuestro, el primero demostrado en el Hospital de Niños J.M. de los Ríos de Caracas. Nuestra paciente es hija de padres consanguíneos, con 3 hermanos de igual sexo fallecidos con igual sintomatología, es decir orinas rojas desde el nacimiento, fotosensibilidad de piel, eritrodoncia, uñas rojas, anemia hemolítica, esplenomegalia y que luego de comprobado el diagnóstico con la determinación de copro y uroporfirina en orina, se trató con protector solar (dioxido de titanio), Beta carotenos orales (Solatene) esplenectomía con aplicación prevía de vacuna antineumococcica (NeumoVac) y recientemente el egregado de carbón medicinal por vía oral. Su evolución ha sido favorable hasta el momento
