Mercury in aquatic ecosystems of two indigenous communities in the Piedmont Ecuadorian Amazon: evidence from fish, water, and sediments.

Mercury is a highly toxic element present in water, soil, air, and biota. Anthropogenic activities, such as burning fossil fuels, mining, and deforestation, contribute to the presence and mobilization of mercury between environmental compartments. Although current research on mercury pathways has advanced our understanding of the risks associated with human exposure, limited information exists for remote areas with high diversity of fauna, flora, and indigenous communities. This study aims to deepen our understanding of the presence of total mercury in water, sediments, and fish, within aquatic ecosystems of two indigenous territories: Gomataon (Waorani Nationality) and Sinangoé (Ai´Cofán Nationality) in the Ecuadorian Amazon. Our findings indicate that, for most fish (91.5%), sediment (100%) and water (95.3%) samples, mercury levels fall under international limits. For fish, no significant differences in mercury levels were detected between the two communities. However, eight species exceeded recommended global limits, and one surpassed the threshold according to Ecuadorian legislation. Piscivore and omnivore fish exhibited the highest concentrations of total mercury among trophic guilds. Only one water sample from each community's territory exceeded these limits. Total mercury in sediments exhibited greater concentrations in Gomataon than Sinangoé. Greater levels of mercury in sediments were associated with the occurrence of total organic carbon. Considering that members of the communities consume the analyzed fish, an interdisciplinary approach, including isotopic analysis, methylmercury sampling in humans, and mercury monitoring over time, is imperative for a detailed risk assessment of mercury exposure in Amazonian communities.

High-energy alkaline milling as a potential physical and chemical cornstarch ecofriendly treatment to produce nixtamalized flours.

In this study, hard corn grains were nixtamalized (alkali-heat treatment) by a high-energy ball mill to investigate the effects on its physicochemical, textural, and microstructural properties. Ball milling modifies the structure and properties of cornstarch. The gelatinization peak of starch was evidenced and thermal and pasting properties were significantly affected. With regard to rheological properties, the viscosity peak increased from 2454 cP in traditional nixtamalized flour to 4294 cP in high-energy milling treatments with 1.4% of Ca(OH)2 and 20% moisture content, C1.4, while enthalpy ranged from 3.5 to 0.34 J/g, respectively. High-energy milling influenced the Fourier-Transform InfraRed Spectroscopic (FT-IR) patterns. All of the samples of the corn-grain starches presented the typical A-type X-ray diffraction pattern. The crystallinity of starch from CG showed a lower intensity in peaks 2θ ~ 15 and 23° compared with starch from WG and YG. The textural properties of the masas were influenced, adhesiveness was reduced, but cohesiveness was increased by the addition of Ca(OH)2. In the structural characterization by E-SEM, the control presented a greater amount of agglomerated starch granules, followed by the high-energy milling treatments. The results suggest that high-energy alkaline milling could be a potential physical and chemical method to modify corn-starch properties and obtain nixtamalized products.

Physico-chemical, thermal, and rheological properties of nixtamalized creole corn flours produced by high-energy milling.

High-energy milling (HEM) was used to produce nixtamalized corn flours, the traditional nixtamalization process was used as a control. Four creole grains were stone-milled, adjusted to an appropriate moisture content and calcium hydroxide concentration and milled using HEM. The physicochemical, thermal, and rheological characteristics of the flours and corn masas were affected by the HEM process. Negritas and Ahualulco creole grains nixtamalized by HEM showed similar viscosity profiles as a control. HEM reduced the gelatinization enthalpy compared to control and raw flours. Diffractograms showed changes in the crystalline structures and FT-IR demonstrated different regions for lipids, proteins, and carbohydrates in all control and treated grains. The texture of corn masas revealed significant differences according to the grain type. ESEM analysis showed smaller particles of HEM flours compared to those of the control. HEM could be a faster, non-pollutant, energy-saving, alternative nixtamalization process.

Phytophthora capsici epidemic dispersion on commercial pepper fields in Aguascalientes, Mexico.

Chili pepper blight observed on pepper farms from north Aguascalientes was monitored for the presence of Phytophthora capsici during 2008-2010. Initially, ELISA tests were directed to plant samples from greenhouses and rustic nurseries, showing an 86% of positive samples. Later, samples of wilted plants from the farms during the first survey were tested with ELISA. The subsequent survey on soil samples included mycelia isolation and PCR amplification of a 560 bp fragment of ITS-specific DNA sequence of P. capsici. Data was analyzed according to four geographical areas defined by coordinates to ease the dispersal assessment. In general, one-third of the samples from surveyed fields contained P. capsici, inferring that this may be the pathogen responsible of the observed wilt. Nevertheless, only five sites from a total of 92 were consistently negative to P. capsici. The presence of this pathogen was detected through ELISA and confirmed through PCR. The other two-thirds of the negative samples may be attributable to Fusarium and Rhizoctonia, both isolated instead of Phytophthora in these areas. Due to these striking results, this information would be of interest for local plant protection committees and farmers to avoid further dispersal of pathogens to new lands.

Frecuencia de efectos adversos en usuarias de implante subdérmico / Frequency of adverse effects in users with implants subskin

Resumen

Introducción: el implante subdérmico es un método de liberación prolongada de solo progestina, a través de la pared de una cápsula colocada debajo de la piel. El concepto de anticonceptivo mediante implante de liberación prolongada fue propuesto en 1967 por el Population Council. En México, Implanon se encuentra disponible desde el 2001 en el cuadro básico de las principales instituciones de salud.

Objetivo: determinar la frecuencia de efectos adversos en las usuarias del implante subdérmico.

Metodología: se realizó un estudio descriptivo en el que se aplicó una encuesta a 162 usuarias de una unidad de medicina familiar del Instituto Mexicano del Seguro Social (IMSS). El instrumento se validó por expertos y una prueba piloto.

Resultados: el promedio de edad de las usuarias fue de 25.2 años, con una desviación estándar ± 4.5. El 28.3 % de las usuarias de implante subdérmico presentó efectos adversos, destacando los siguientes: 36 % alteraciones en el ciclo menstrual, cefalea el 28 %, ganancia de peso 12 %, mareos 12 % y cambios en el estado de ánimo 12 %.

Conclusiones: aunque los implantes se encuentran dentro de los métodos anticonceptivos más efectivos la frecuencia de lo efectos adversos en usuarias con implante subdérmico podría provocar el abandono del uso de éste método.

Summary

Introduction: it implants subskin is a method of prolonged liberation of only progestinas, through the wall of capsules placed underneath the skin. The concept of contraceptive by means of implants of prolonged liberation was proposed in 1967 by the Population Council. In Mexico, Implanon is available from the 2001 in the basic picture of the IMSS, ISSSTE and SSA.

Objective: to determine the frequency of adverse effects in the users with implants subskin.

Methodology: study was realized descriptive survey, to 162 users of the Familiar Medicine Unit 46. A valuation instrument was elaborated on the frequency of adverse effects of implants subskin, which validated by two rounds of experts and one pilot test.

Results: the average of age of the users was of 25.2 years, with a standard deviation ± 4.5. 28.3 % of the users with implant subskin presented/displayed adverse effects, emphasizing the following: 36 % alterations in the menstrual cycle, headache 28 %, increase of weight 12 %, mareos 12 % and changes in the mood 12 %.

Conclusions: the frequency of adverse effects in users with implants subskin is significant and agrees with other realized investigations.

Leiomiosarcoma hepático reporte de un caso y revisión de la literatura / Hepatic leiomiosarcoma report of a case and literature review

Se presenta el caso de paciente masculino de 20 años, quien en el mes de febrero de 2005, presenta debilidad general y pérdida de peso progresiva cuantificada en 8 kg. Desde inicio de marzo de 2005 evidencia palidez cutánea, hipertermia precedida de escalofríos, de predominio vespertino, dolor en epigastrio, opresivo, no irradiado, motivo por el cual consulta a facultativo en su localidad, donde es hospitalizado. Permanece 30 días, recibiendo tratamiento con antibióticos sin mejoría, ameritando transfundir por presentar hemoglobina de 6 g/dL, sin sitio evidente de sangrado. Ecosonograma abdominal: hepatoesplenomegalia y LOE lóbulo hepático izquierdo, gastroscopia y colonoscopia normal. Resonancia magnética abdominal: evidencia de hepatomegalia asociado a la presencia de lesión de apariencia tumoral en el lóbulo hepático izquierdo, con realce heterogéneo. La evolución no fue la de un absceso hepático y la imagen ecosonográfica es de comportamiento sólido, por lo que se solicita a cirugía laparoscopia diagnóstica. Se descarta la posibilidad de toma percútanea guiada por eco en vista de alta posibilidad de sangrado. Se practica hepatectomía izquierda, biopsia: reporta: leiomiosarcoma hepático. Luego de la cirugía el paciente evoluciona satisfactoriamente. A pesar de su poca frecuencia, los sarcomas hepáticos deben tomarse en cuenta en el diagnóstico diferencial de tumores hepáticos sólidos en el adulto, en ausencia de cirrosis. El único tratamiento que permite expectativas de supervivencia es quirúrgico, mediante hepatectomías regladas o “atípicas” con márgenes de seguridad e incluso en algunos casos trasplante hepático.

Disfunción tiroidea asociada al tratamiento con interferon alfa en pacientes con hepatitis C crónica / Dysfuction thyroid asociated the treatment qith interferon alpha in patients with hepatitis C chronic

Durante el tratamiento de la Hepatitis C crónica, el interferón alfa es capaz de inducir disfunción tiroidea con varias manifestaciones clinicas. El hipotiroidismo es más común que el hipertiroideismo. Se ha descrito también hipertoroidismo seguido por hipotiroidismo. Los síntomas clínicos varían desde ser subclínico hasta mostrar manifestaciones severas de la enfermedad. La disfunción puede persistir después de descontinar el tratamiento con interferón. Hipotiroidismo es fácilmente controlable con reemplazo con L-thyronina, si es necesario, y la regresión se puede observar luego de omitir el tratamiento con interferón. Los casos casos de hipertiroidismo deben ser bien evaluados. El desarrollo de anticuerpos anti tiroideos o incremento de títulos de dichos anticuerpos ha sido observado durante el tratamiento con interferón alfa, sugiriendo la existencia de mecanismo inmunológico para aclarar la asociación entre la infección por el virus de la hepatitis C y la autoinmunidad tiroidea, y determinar factores de riesgo para el desarrollo de disfunción de ésta glándula durante el tratamiento con interferón