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Sympathetic activity and cardiovascular risk markers in non-diabetic and diabetic Mexican older adults
(2019-06) García Suarez, Patricia Concepción; Fonseca Viana, Rebeca Baptista; Rentería, Iván; Canton Martínez, Ermilo; Jiménez Maldonado, Alberto; Moncada Jiménez, José
Purpose: To compare the SNS activity and metabolic markers associated to CVD in type 2 diabetic (T2D) and non-diabetic (ND) Mexican older adults. Methods: Volunteers were 11 T2D (Age = 60.8 ± 5.2 yr., body mass index [BMI]= 29.9 ± 4.6 kg/m2) and 17 ND (Age = 64 ± 4.8 yr., BMI = 28.4 ± 4.1 kg/m2) older adults residing in Baja California, Mexico. Morning blood serum samples were collected after 8-h fasting following body composition analysis (InBody 770, Cerritos, CA). A 5-min resting ECG recording (BioRadio, Cleveland, OH) was used to analyze HRV. Time and frequency domain analysis were assessed with Kubios HRV 3.1 software (Kubios Oy, Finland). Results: Between-group differences were found on blood glucose (T2D = 171.9±91.6 vs. ND = 80.17±12.0mg/dL, p < 0.001), and triglycerides (T2D = 266.9±126.17 vs. ND = 60.54 ± 47.8mg/dL, p < 0.02). Non-significant between-group differences were found on cholesterol (T2D = 183.0±45.1 vs. ND = 180.9±29.7mg/dL, p = 0.88), HDLc (T2D = 60.54±55.8 vs. ND = 47.88±20.73mg/dL, p = 0.92) and LDLc levels (T2D = 84.4±44.6 vs. ND = 107.84±26.74mg/dL, p = 0.22). The HR (T2D = 72.6±11.5 vs. ND = 71.7±7.8bpm, p = 1.0), beat-to-beat intervals (RR) (T2D = 845.7±128.7 vs. ND = 843.7±93ms, p = 0.94), Root Mean Square of the Successive Differences (RMSSD) (T2D = 68.7±58.0 vs. ND = 45.6±31.2ms, p = 0.45) and relative successive beats with > 50ms of difference (pNN50) (T2D = 23.4±25.5 vs. ND = 9.7±13.7%, p = 0.32) were similar in both groups. High- (T2D = 48.14±24.64 vs. ND = 45.5±22.9n.u., p= 0.67) and Low-frequency (T2D = 51.7±24.5 vs. ND = 54.0±23.3n.u., p= 0.70) time domains and LF/HF ratio (T2D = 2.0±2.4 vs. ND = 2.4±3.0, p = 0.68) were similar in both groups. Conclusions: Diabetic conditions did not affect substantially SNS activity compared with non-diabetic condition in a sample of Mexican older adults.
A comprehensive review of hypotheses about the biological function of zearalenone, and a new hypothesis for the function of resorcylic and dihydroxyphenylacetic macrolactones in fungi
(2025-05-03) Viñas Meneses, María; Karlovsky, Petr
The special metabolite of Fusarium spp. zearalenone (ZEN) exerts estrogenic effects on mammals, stimulates plant growth, stimulates sexual development in fungi, and inhibits fungal growth. These activities inspired hypotheses about the biological function of ZEN. We briefly review the discovery of ZEN and its implications. The main subject of this review is a critical assessment of the hypotheses that ZEN is a fungal hormone, a plant hormone, a virulence factor, or a fungal defense metabolite. Conceptual and technical issues related to testing these hypotheses, such as inadequate analytical methods, confusion of incidental effects with biological functions, and lack of normalization, are illuminated. Based on these considerations, gene knockout experiments, and on the effects of biotic interactions on ZEN synthesis, we argue that ZEN is a defense metabolite protecting Fusarium spp. against mycoparasites and competitors. Similar reasoning and published data suggest that the Fusarium metabolite fusaristatin A fulfils the same function. Fungi produce many macrolactones of resorcylic acid (RALs) and dihydroxyphenylacetic acid (DHPLs) with properties similar to ZEN. Their widespread occurrence, antifungal activity, and further considerations prompt us to hypothesize that the fundamental function of fungal RALs and DHPLs lies in defense and interference competition.
Tissue damaging toxins in snake venoms: mechanisms of action, pathophysiology and treatment strategies
(2024-03-22) Bittenbinder, Mátyás A.; van Thiel, Jory; Cardoso, Ferrnanda C.; Casewell, Nicholas; Gutiérrez, José María; Kool, Jeroen; Vonk, Freek J.
Snakebite envenoming is an important public health issue responsible for mortality and severe morbidity. Where mortality is mainly caused by venom toxins that induce cardiovascular disturbances, neurotoxicity, and acute kidney injury, morbidity is caused by toxins that directly or indirectly destroy cells and degrade the extracellular matrix. These are referred to as ‘tissue-damaging toxins’ and have previously been classified in various ways, most of which are based on the tissues being affected (e.g., cardiotoxins, myotoxins). This categorisation, however, is primarily phenomenological and not mechanistic. In this review, we propose an alternative way of classifying cytotoxins based on their mechanistic effects rather than using a description that is organ- or tissue-based. The mechanisms of toxin-induced tissue damage and their clinical implications are discussed. This review contributes to our understanding of fundamental biological processes associated with snakebite envenoming, which may pave the way for a knowledge-based search for novel therapeutic options.
Envenenamiento ofídico en Costa Rica: logros y tareas pendientes
(2020-09-03) Gutiérrez, José María; Arias Rodríguez, Jazmín; Alape Girón, Alberto
Objetivo: efectuar un análisis de los logros en Costa Rica en cuanto al problema de los envenenamientos por mordeduras de serpientes, y señalar tareas pendientes para reducir aún más el impacto de esta patología.
Metodología: se efectuó una revisión de bibliografía relacionada con el estudio del envenenamiento ofídico en Costa Rica y con los avances efectuados en el tema, en el país. Paralelamente, se identificaron aspectos que requieren atención en el manejo de esta enfermedad tropical desatendida.
Conclusiones: desde las primeras décadas del siglo XX, se han realizado avances significativos en la comprensión y manejo del problema de los envenenamientos por mordedura de serpiente en Costa Rica. Se ha trabajado desde una visión integral que incluye: investigación científico-tecnológica, producción y distribución de antivenenos, esfuerzos en prevención, capacitación de las personas profesionales de la salud en el diagnóstico y tratamiento, y docencia de grado y posgrado en el tema.
El país ha asumido un papel de liderazgo a nivel internacional, tanto en el plano académico como en la provisión de antivenenos a muchos países. No obstante, aún quedan aspectos del problema que requieren nuevos esfuerzos en nuestro medio, sobre todo en lo referente a la atención de las consecuencias biomédicas, psicológicas, sociales y económicas que sufren las personas afectadas.
Descriptores: antivenenos, mordeduras de serpientes, venenos.
A meta-analysis of the effect of small-sided games on the repeated sprint ability in soccer
(2020-12-18) Morera Siércovich, Pier Luigi; Moncada Jiménez, José
To determine the effect of small-sided games (SSG) on the repeated sprint ability (RSA) in male soccer players. A meta-analysis was conducted in which studies were selected from the electronic databases Medline, SPORTDiscus, Google Scholar, and PubMed. Results: Six studies were included and 44 effect sizes (ES) were computed from 116 men (age = 18.0 ± 2.8 yr., height = 175.8 ± 3.3 cm, weight = 68.6 ± 5.6 kg, body mass index [BMI] = 22.3 ± 1.1 kgm2, VO2max = 56.9 ± 2.1 mlkg-1min-1). The SSG training improved the overall RSA performance (ES = -.54, 95%CI = -.89, -.20, p < .05), reduced RSA total time (ES = -.41, 95%CI = -.81, -.01, p < .05), and fatigue index (ES = -.83, 95%CI = -1.65, -.02, p < 0.05). Moderator analysis showed that the fatigue index is impaired when several sessions/week are performed (β = .69, 95%CI = .29, 1.10, R2 = 82.9, p = .001) and is enhanced when the duration of the intervention is extended over several weeks (β = -.25, 95%CI = -.47, -.03, R2 = 56.6, p = .05). The methodological use of SSG enhances the capacity of repeated sprints, while technical and tactical elements are worked concomitantly.