Monitoreo de vibrio spp. en ostiones Crassostrea virginica de las lagunas de Tamiahua y Tampamachoco, Veracruz, México

Vibrio es un género ampliamente distribuído en ambientes estuarinos y marinos, adaptable y con rápida propagación de sus cepas. Los moluscos bivalvos son reservorios potenciales de Vibrios, su consumo está relacionado con el desarrollo de vibriosis leve como gastroenteritis hasta septicemia grave o la muerte. Por lo cual es importante el monitoreo continuo en las áreas de extraccion y distribución para evaluar el riesgo para la salud humana derivado del consumo de moluscos y garantizar la inocuidad de estos bivalvos. En el presente estudio se determinaron las diferencias estacionales en la presencia y abundancia de Vibrios durante las fases de recolección (bancos ostrícolas) y post-recolección (cooperativas y restaurantes) en ostiones Crassostrea virginica de las lagunas de Tamiahua y Tampamachoco, Veracruz, México. Las muestras fueron obtenidas de trece sitios al azar durante el año 2018. El aislamiento bacteriano se realizó por el método de siembra por dilución en medio TCBS y recuento en placa de acuerdo a la NOM-031-SSA1-1993. El análisis estadístico indicó que no existieron diferencias espaciales significativas, no obstante, se presentaron diferencias estacionales. En esta investigación, se evidencia por primera vez, la presencia de Vibrio spp. en ostiones de las cooperativas de estudio. También se reporta la ausencia de este género bacteriano en los restaurantes adyacentes. En general, los resultados muestran la necesidad de aplicar medidas dirigidas a reducir la presencia de Vibrios durante la fase de post-recolección de ostiones, con la finalidad de disminuir el riesgo de infección por Vibrio spp. en los consumidores

Degradación de los plaguicidas endosulfán y malatión por cepas bacterianas aisladas de suelo agrícola

Tesis de Maestría presentada a la Facultad de Ciencias Biológicas y Agropecuarias de la Universidad Veracruzana. Región Poza Rica-Tuxpa

Editorial: Brain-Liver Axis and Glutamate Homeostasis.

Glutamate has long been recognized as the main excitatory neurotransmitter. It requires the involvement of both neurons and glial cells to elicit its function as a neurotransmitter, in what has been known as a tripartite synapse (Martínez-Lozada and Ortega, 2015). Glutamate in the synaptic cleft is tightly regulated mostly by glial transporters, EAATs, avoiding overstimulation of glutamate receptors and preventing an excitotoxic insult (Danbolt, 2001). Glutamate taken up by astrocytes is converted to glutamine by glutamine synthetase and released and internalized by neurons to be converted back to glutamate through the glutamate/glutamine shuttle (McKenna et al., 2012; Martínez-Lozada and Ortega, 2015). [...

Bisphenol A exposure disrupts aspartate transport in HepG2 cells

The liver is the organ responsible for bisphenol A (BPA) metabolism, an environmental chemical agent. Exposure to this toxin is associated with liver abnormalities and dysfunction. An important role played by excitatory amino acid transporters (EAATs) of the slc1 gene family has been reported in liver injuries. To gain insight into a plausible effect of BPA exposure in the liver glutamate/aspartate transport, using the human hepatoblastoma cell line HepG2, we report a BPA-dependent dynamic regulation of SLC1A3 and SLC1A2. Through the use of radioactive [ H]- d-aspartate uptake experiments and immunochemical approaches, we characterized time and dose-dependent regulation of the protein levels and function of these transporters after acute exposure to BPA. An increase in nuclear Yin Yang 1 was found. These results suggest an important involvement of the EAATs in liver physiology and its disruption after acute BPA exposure

Bisphenol A exposure disrupts aspartate transport in HepG2 cells.

The liver is the organ responsible for bisphenol A (BPA) metabolism, an environmental chemical agent. Exposure to this toxin is associated with liver abnormalities and dysfunction. An important role played by excitatory amino acid transporters (EAATs) of the slc1 gene family has been reported in liver injuries. To gain insight into a plausible effect of BPA exposure in the liver glutamate/aspartate transport, using the human hepatoblastoma cell line HepG2, we report a BPA-dependent dynamic regulation of SLC1A3 and SLC1A2. Through the use of radioactive [ H]- d-aspartate uptake experiments and immunochemical approaches, we characterized time and dose-dependent regulation of the protein levels and function of these transporters after acute exposure to BPA. An increase in nuclear Yin Yang 1 was found. These results suggest an important involvement of the EAATs in liver physiology and its disruption after acute BPA exposure

Acute Liver Toxicity Modifies Protein Expression of Glutamate Transporters in Liver and Cerebellar Tissue

Glutamate is the main excitatory amino acid acting at the level of pre and postsynaptic neurons, as well as in glial cells. It is involved in the coordinated modulation of energy metabolism, glutamine synthesis, and ammonia detoxification. The relationship between the functional status of liver and brain has been known for many years. The most widely recognized aspect of this relation is the brain dysfunction caused by acute liver injury that manifests a wide spectrum of neurologic and psychiatric abnormalities. Inflammation, circulating neurotoxins, and impaired neurotransmission have been reported in this pathophysiology. In the present contribution, we report the effect of a hepatotoxic compound like CCl4 on the expression of key proteins involved in glutamate uptake and metabolism as glutamate transporters and glutamine synthetase in mice liver, brain, and cerebellum. Our findings highlight a differential expression pattern of glutamate transporters in cerebellum. A significant Purkinje cells loss, in parallel to an up-regulation of glutamine synthetase, and astrogliosis in the brain have also been noticed. In the intoxicated liver, glutamate transporter 1 expression is up-regulated, in contrast to glutamine synthetase which is reduced in a time-dependent manner. Taken together our results demonstrate that the exposure to an acute CCl4 insult, leads to the disruption of glutamate transporters expression in the liver-brain axis and therefore a severe alteration in glutamate-mediated neurotransmission might be present in the central nervous system

Efecto de la temperatura sobre la bioacumulación de hidrocarburos en el Ostión americano Crassostrea virginica

Several studies show the effect of temperature on the bioaccumulation of contaminants in bivalve mollusks, but the influence of this factor on the bioaccumulation of hydrocarbons (HC) in Crassostrea virginica has not been reported. In this work the effect of temperature on HC accumulation in C. virginica under controlled conditions, survival rate (SR) and gametogenic development was studied. Four treatments with different temperatures and an HC concentration were studied: A (without HC at 26 °C), B (with HC at 30 °C), C (with HC at 26 °C) and D (with HC a 30 °C) and the control (without HC at ambient temperature). Results showed that the control and treatments A and B had the lowest HC bioaccumulation values with amounts below 30 mg kg-1. In treatment C, accumulation values of 83 mg kg-1 were obtained, while treatment D recorded the highest HC level, 118 mg kg-1, and the lowest SR (53 %). The highest SR (93 %) was recorded in the control and treatments A and C. At the cellular level no pathology was identified, but gonadal development was affected by the presence of HC and the temperature of 30 °C, with little gonadal growth and indefinite organisms predominating. The different temperatures did not influence HC bioaccumulation in the organisms, but a negative effect on gametogenic development and SR was observed.Diversos estudios muestran el efecto de la temperatura en la bioacumulación de contaminantes en moluscos bivalvos, pero la influencia de esté factor en la bioacumulación de hidrocarburos (HC) en Crassostrea virginica no se ha reportado. En este trabajo se estudió el efecto de la temperatura sobre la acumulación de HC en C. virginica en condiciones controladas, la tasa de sobrevivencia (TS) y el desarrollo gametogénico. Se aplicaron cuatro tratamientos con diferentes temperaturas y concentración de HC: A (sin HC a 26 °C), B (sin HC a 30 °C), C (con HC a 26 °C) y D (con HC a 30 °C) y el control (sin HC a temperatura ambiente). Los resultados mostraron que el control y los tratamientos A y B tuvieron los valores más bajos de bioacumulación de HC con cantidades menores de 30 mg kg-1. En el tratamiento C se estimaron valores de acumulación de 83 mg kg-1. Mientras que en el tratamiento D se registraron los niveles más altos de HC con 118 mg kg-1 y la TS más baja (53 %). La TS mayor (93 %) se registró en el control y los tratamientos A y C. A nivel celular no se identificó ninguna patología, pero el desarrollo gonádico fue afectado por la presencia de HC y la temperatura de 30°C, con escaso crecimiento gonadal, predominando organismos indefinidos. Las diferentes temperaturas no influyeron en la bioacumulación de HC en los organismos, pero se observa efecto negativo en el desarrollo gametogénico y la TS

Effects of SRI-32743, a Novel Quinazoline Structure-Based Compound, on HIV-1 Tat and Cocaine Interaction with Norepinephrine Transporter

Prolonged exposure to HIV-1 transactivator of transcription (Tat) protein dysregulates monoamine transmission, a physiological change implicated as a key factor in promoting neurocognitive disorders among people living with HIV. We have demonstrated that in vivo expression of Tat in Tat transgenic mice decreases dopamine uptake through both dopamine transporter (DAT) and norepinephrine transporter (NET) in the prefrontal cortex. Further, our novel allosteric inhibitor of monoamine transporters, SRI-32743, has been shown to attenuate Tat-inhibited dopamine transport through DAT and alleviates Tat-potentiated cognitive impairments. The current study reports the pharmacological profiles of SRI-32743 in basal and Tat-induced inhibition of human NET (hNET) function. SRI-32743 exhibited less affinity for hNET binding than desipramine, a classical NET inhibitor, but displayed similar potency for inhibiting hDAT and hNET activity. SRI-32743 concentration-dependently increased hNET affinity for [3H]DA uptake but preserved the Vmax of dopamine transport. SRI-32743 slowed the cocaine-mediated dissociation of [3H]Nisoxetine binding and reduced both [3H]DA and [3H]MPP+ efflux but did not affect d-amphetamine-mediated [3H]DA release through hNET. Finally, we determined that SRI-32743 attenuated a recombinant Tat1–86-induced decrease in [3H]DA uptake via hNET. Our findings demonstrated that SRI-32743 allosterically disrupts the recombinant Tat1–86–hNET interaction, suggesting a potential treatment for HIV-infected individuals with concurrent cocaine abuse