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In response to diabetes mellitus, skeletal muscle is negatively affected, as is evident by reduced contractile force production, increased muscle fatigability, and increased levels of oxidative stress biomarkers. Apocynin is a widely used NADPH oxidase inhibitor, with antioxidant and anti-inflammatory potential. It has been effective for amelioration of a variety of disorders, including diabetic complications. Therefore, the present study was conducted to evaluate the effects and action mechanisms of apocynin in slow- and fast-twitch diabetic rat muscles. Male Wistar rats were rendered diabetic by applying intraperitoneally a single dose of streptozotocin (45 mg/kg). Apocynin treatment (3 mg/kg/day) was administered over 8 weeks. Fasting blood glucose (FBG), insulin tolerance and body weight gain were measured. Both slow (soleus) and fast (extensor digitorum longus, EDL) skeletal muscles were used for muscle function evaluation, oxidative stress markers, and evaluating gene expression using qRT-PCR. Treatment with apocynin significantly reduced FBG levels and enhanced insulin tolerance. Apocynin also prevented muscle contractile dysfunction in EDL muscle but had no significant effect on this parameter in soleus muscles. However, in both types of muscles, apocynin mitigated the oxidative stress by decreasing ROS levels and increasing total glutathione levels and redox state. Concomitantly, apocynin also statistically enhanced Nrf-2 and GLU4 mRNA expression and downregulated NOX2, NOX4, and NF-κB mRNA. Collectively, apocynin exhibits properties myoprotective in diabetic animals. These findings indicate that apocynin predominantly acts as an antioxidant in fast-twitch and slow-twitch muscles but has differential impact on contractile function.

RESUMO

In the actual mining scenario, copper bioleaching, mainly raw mined material known as run-of-mine (ROM) copper bioleaching, is the best alternative for the treatment of marginal resources that are not currently considered part of the profitable reserves because of the cost associated with leading technologies in copper extraction. It is foreseen that bioleaching will play a complementary role in either concentration-as it does in Minera Escondida Ltd. (MEL)-or chloride main leaching plants. In that way, it will be possible to maximize mines with installed solvent-extraction and electrowinning capacities that have not been operative since the depletion of their oxide ores. One of the main obstacles for widening bioleaching technology applications is the lack of knowledge about the key events and the attributes of the technology's critical events at the industrial level and mainly in ROM copper bioleaching industrial operations. It is relevant to assess the bed environment where the bacteria-mineral interaction occurs to learn about the limiting factors determining the leaching rate. Thus, due to inability to accurately determine in-situ key variables, their indirect assessment was evaluated by quantifying microbial metabolic-associated responses. Several candidate marker genes were selected to represent the predominant components of the microbial community inhabiting the industrial heap and the metabolisms involved in microbial responses to changes in the heap environment that affect the process performance. The microbial community's predominant components were Acidithiobacillus ferrooxidans, At. thiooxidans, Leptospirillum ferriphilum, and Sulfobacillus sp. Oxygen reduction, CO2 and N2 fixation/uptake, iron and sulfur oxidation, and response to osmotic stress were the metabolisms selected regarding research results previously reported in the system. After that, qPCR primers for each candidate gene were designed and validated. The expression profile of the selected genes vs. environmental key variables in pure cultures, column-leaching tests, and the industrial bioleaching heap was defined. We presented the results obtained from the industrial validation of the marker genes selected for assessing CO2 and N2 availability, osmotic stress response, as well as ferrous iron and sulfur oxidation activity in the bioleaching heap process of MEL. We demonstrated that molecular markers are useful for assessing limiting factors like nutrients and air supply, and the impact of the quality of recycled solutions. We also learned about the attributes of variables like CO2, ammonium, and sulfate levels that affect the industrial ROM-scale operation.

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RESUMO

Resumen: La diabetes mellitus se ha convertido en un problema de salud pública en el mundo, ya que su incidencia y prevalencia se ha incrementado de manera exponencial en las últimas décadas, lo que ha traído consigo un aumento en las complicaciones agudas y crónicas asociadas a su diagnóstico tardío y poco apego a su tratamiento. Los pacientes con diabetes mellitus tienen una mayor probabilidad de requerir una cirugía en comparación con la población general, quienes podrían llegar a presentar complicaciones graves asociadas al evento quirúrgico como hipertensión, cardiopatía isquémica, nefropatía y neuropatía autonómica, las cuales se deben a un incremento de la resistencia a la insulina y a la hiperglucemia. Por lo anterior, el control metabólico es pieza clave en la conducta perioperatoria del paciente con diabetes mellitus donde la participación de un equipo multidisciplinario (médico internista, cirujano y anestesiólogo) definan de manera conjunta las mejores estrategias quirúrgicas y anestésicas para un mejor desenlace previo, durante y posterior a la cirugía.

Abstract. Diabetes mellitus has become a public health problem worldwide, its incidence and prevalence have exponentially increased in recent decades, bringing with it an increase in acute and chronic complications associated with late diagnosis and failure of adherence to treatment. Patients with diabetes mellitus are more likely to require surgery compared to the general population, they may have serious complications associated with the surgical event such as hypertension, ischemic heart disease, nephropathy and autonomic neuropathy, due to an increase in insulin resistance and hyperglycemia. Therefore, metabolic control is a key element in the perioperative behavior of patients with diabetes mellitus where the joint collaboration of a multidisciplinary team (internist, surgeon and anesthesiologist) to define the best surgical and anesthetic strategies for a better outcome before, during and after surgery.

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Carcinoides gástricos son tumores raros originados de la células enterocromaffin-like de la mucosa no antral. Sin embargo, la prevalencia es mucho mayor en pacientes con hipergastrinemia, como en la anemia perniciosa, aclorhidria, síndrome de Zollinger-Ellison y estados de baja acidez. La mayoría de estos tumores son de crecimiento lento, con bajo porcentaje de metástasis, en especial hígado y ganglios linfáticos. Los carcinoides gástricos han sido clasificados en tres subtipos, con el fin de determinar el pronóstico y la terapia más adecuada. Presentamos un caso de tumor carcinoide gástrico en un masculino de 28 años que fue manejado en el Hospital San Juan de Dios.

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