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Cetaceans exhibit physiological adaptations that allowed the transition to aquatic life, including a robust antioxidant defense system that prevents injury from repeated exposure to ischemia/reperfusion events associated with breath-hold diving. The signaling cascades that characterize ischemic inflammation in humans are well characterized. In contrast, cetaceans' molecular and biochemical mechanisms that confer tolerance to inflammatory events are poorly understood. Heme oxygenase (HO) is a cytoprotective protein with anti-inflammatory properties. HO catalyzes the first step in the oxidative degradation of heme. The inducible HO-1 isoform is regulated by various stimuli, including hypoxia, oxidant stress, and inflammatory cytokines. The objective of this study was to compare the response of HO-1 and cytokines to a proinflammatory challenge in leukocytes isolated from humans and bottlenose dolphins (Tursiops truncatus). We measured changes in HO activity, and abundance and expression of interleukin 1 beta (IL-1ß), interleukin 6 (IL-6), tumor necrosis factor-alpha (TNF-α), and heme oxygenase 1 (HMOX1) in leukocytes treated with lipopolysaccharide (LPS) for 24 and 48 h. HO activity increased (p < 0.05) in dolphin (48 h) but not human cells. TNF-α expression increased in human (24 h, 48 h), but not dolphin cells following LPS stimulation. LPS-induced cytokine expression was lower in dolphin than in human leukocytes, suggesting a blunted cytokine response in bottlenose dolphin leukocytes treated with LPS. Results suggest species-specific regulation of inflammatory cytokines in leukocytes treated with LPS, which may lead to differential responses to a pro-inflammatory challenge between marine and terrestrial mammals.

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The red crab, Pleuroncodes planipes, is a decapod crustacean abundant off the Pacific coast of the Baja California Peninsula. This species is caught and used in preparing animal feed, such as flour, particularly for aquaculture. Levels of calcium (Ca), cadmium (Cd), copper (Cu), iron (Fe), lead (Pb), magnesium (Mg), manganese (Mn), nickel (Ni), phosphorus (P), and zinc (Zn) were measured in red crabs collected from three geographic zones during three cruises in different seasons. Significant differences were found in the levels of Ca, Cd, Cu, Fe, Mg, Ni, P, and Zn between the two El Niño years (cruises C1 and C3, based on a threshold of ±0.5 °C for the Oceanic Niño Index). The highest concentrations of most elements were observed in the south of the Baja California Peninsula, a highly productive area influenced by upwelling events. Our findings suggest that while environmental temperature plays a central role in the benthic or pelagic distribution of red crabs, their content and variability of trace and macro elements appear to be associated with the presence of oceanic conditions, such as upwelling and potential changes in the composition of their diet associated with the depth in which these crustaceans are collected.

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BACKGROUND: Phthalates, plasticizers that are widely used in consumer products including toys, cosmetics, and food containers, have negative effects in liver, kidney, brain, lung and reproductive system of humans and other mammals. OBJECTIVES: To summarize, describe and discuss the available information on the effects of phthalate exposure in mammals, with emphasis on oxidative stress, and to suggest potential biomarkers of the health risks associated with phthalate exposure. METHODS: An assessment of scientific journals was performed using the PRISMA model for systematic reviews. Manuscripts reporting effects of phthalate exposure on mammalian health published in the last decade were selected according to originality, content, and association to health hazards. RESULTS AND DISCUSSION: We identified 25 peer-reviewed articles published between January 1st, 2010 and June 1st, 2021 that fit the aims and selection criteria. Phthalates induce oxidative stress and cell degenerative processes by increasing intracellular reactive species. Antioxidant cytoprotective systems decrease with time of exposure; conversely, oxidative damage markers, including thiobarbituric acid-reactive substances (TBARS), 8-hydroxy-2'-desoxyguanosine (8-OHdG) and malondialdehyde (MDA), increase. Phthalates were associated with endocrine system disfunction, metabolic disorders, infertility, nonviable pregnancy, cell degeneration, growth impairment, tumor development, and cognitive disorders. Phthalates can also aggravate health conditions such as asthma, hepatitis, diabetes, allergies, chronic liver and kidney diseases. Among humans, the more vulnerable subjects to phthalate exposure effects were children and individuals with a prior health condition. CONCLUSION: Chronic exposure to phthalates induces oxidative stress in mammals with concomitant adverse effects in reproductive, respiratory, endocrine, circulatory, and central nervous systems in both in vitro and in vivo trials. Oxidative damage markers and phthalate metabolites levels were the most common biomarkers of phthalate exposure effects. Studies in free-ranging and wild mammals are nil. Further studies on the pathways that lead to metabolic disruption are needed to identify potential treatments against phthalate-induced detrimental effects.

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SUMMARY: Di-(2-ethylhexyl) phthalate (DEHP) is among the most common plasticizer additives that humans are in contact with daily. DEHP can be released from plastic and enter the human body, whereby it is metabolized and transformed into oxidative hydrophilic molecules. Clinical follow-ups in patients exposed to this phthalate and investigations in cultures of several cell types have provided information on its effects. For example, it is associated with inhibition of diploid human cell development and morphological changes in cultured germ cells. Although skeletal muscle represents around 50 % of the human body mass, knowledge about the effects of DEHP on this tissue is poor. Cultured skeletal muscle cells were exposed to DEHP (1 mM) for 13 days with the aim of exploring and evaluating some of the potential morphological effects. Three culture development parameters and nine cell characteristics were monitored during the bioassay. At 13 days, growth area, cell viability, and concentration of total proteins were lower in DEHP exposed than in control cells. Cell width and area, as well as the diameter of the nucleus and nucleolus, were greater in exposed cells than in control cells. These are interpreted as signs of cytotoxicity and suggest potential adverse effects on the development of skeletal muscle cells from DEHP exposure, as reported for other cell types.

RESUMEN: Diariamente los seres humanos tenemos contacto con aditivos plastificantes, el di-(2-etilhexil) ftalato (DEHP) se encuentra entre los más comunes. El DEHP puede liberarse del plástico e ingresar al cuerpo humano, donde es metabolizado y transformando en moléculas hidrofílicas oxidativas. Seguimientos en pacientes expuestos a este ftalato e investigaciones en cultivos de varios tipos celulares han aportado información sobre sus efectos. El DEHP es asociado con la inhibición del desarrollo de células humanas diploides y cambios morfológicos en células germinales en cultivo. Sin embargo, aún es poco lo que se sabe sobre los efectos en el músculo esquelético, a pesar de que este tejido representa alrededor del 50 % de la masa corporal del humano. Para explorar y evaluar algunos efectos morfológicos en células de músculo esquelético, cultivos primarios fueron expuestos a DEHP (1 mM) durante 13 días. Se dio seguimiento a tres parámetros de desarrollo del cultivo y nueve características celulares. Al término de 13 días de exposición, los valores del área de crecimiento, viabilidad celular y concentración de proteínas totales fueron inferiores con respecto a los cultivos control. Se observaron cambios morfométricos en las células expuestas. Particularmente, el ancho y área celular, así como los diámetros del núcleo y nucleolos, fueron mayores a los registros en las células control. Estos resultados se interpretan como signos de citotoxicidad y sugieren efectos potencialmente adversos en el desarrollo de las células del músculo esquelético ante una exposición al DEHP, como se ha registrado para otros tipos celulares.

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SUMMARY: The study of cell morphology has contributed to the innovation of clinical techniques and biomedical research. Primary cell culture techniques are well standardized; however, knowledge about morphometric parameters under cell culture conditions is scarce. Variations in morphology can affect cell physiology and responses. The aim of this study was to use morphometric tools to describe the growth and development of skeletal muscle cells under standard cell culture conditions. A photographic database was generated, and morphometric data was obtained for nine cell characteristics (n = 559 cells). Four muscular cell shapes (spherical, irregular outline, triangular and spindle/fusiform) were characterized with wide ranges in variation. The maximum cell length (110-262 µm), width (35-66 µm), area (2,642 - 9,480 µm2), projection lengths (45 - 127 µm), and nucleus diameter (28 ± 11 µm) were obtained by day 23 of culture. A single centrally positioned nucleus was observed in each cell; nucleoli diameter (5 ± 2 µm) and number (1 - 5) varied. In general, cyclic changes in cell sizes were identified during culture, whereas cell length, width, and area increased in spurts. These results suggest that morphometric parameters can be used to monitor skeletal muscle cell development under standard culture conditions.

RESUMEN: A partir de células madre musculares, surgen los mioblastos que se dividen y fusionan entre sí para formar a los miocitos. Estas células ya diferenciadas son precursoras de miocitos que maduran en fibras musculares y posteriormente forman los músculos. La implementación de cultivos celulares de mioblastos ha permitido obtener conocimiento detallado del tejido muscular. Particularmente, algunas de las aportaciones morfológicas fueron el punto de partida de técnicas clínicas, terapias o investigaciones biomédicas. Sin embargo, los estudios morfométricos en condiciones de cultivo celular son escasos. Por lo cual, realizamos seguimientos fotográficos a cultivos desarrollados bajo condiciones estándar, registramos datos para nueve características celulares y aplicamos técnicas morfométricas para analizar estas células (n = 559). Se caracterizaron cuatro formas celulares adoptadas por los mioblastos (esférica, irregular, triangular y huso) y se registraron intervalos amplios de variación en los caracteres. Hacia el día 23 de cultivo se presentaron los valores máximos en la longitud (110-262 µm), el ancho (35-66 µm) y el área celular (2,642-9,480 µm2), así como en el tamaño máximo de las proyecciones celulares (45-127 µm) y el diámetro del núcleo (28±11 µm). El núcleo se observó como único y en posición central; los nucleolos variaron poco en diámetro (5±2 µm), aunque no en número (1 a 5). En términos generales, se identificaron cambios cíclicos en la talla de las células durante los cultivos, esto es, períodos intercalados de incremento y decremento en el largo, ancho y área celular. Debido a que estas características reflejaron los cambios generales sufridos por los mioblastos durante el cultivo, se proponen para monitorear sus etapas de desarrollo en cultivo.

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INTRODUCTION: Acetic acid (AA) has been commonly used in medicine as an antiseptic agent for the past 6000 years. This study evaluated the antibacterial effect of AA during an outbreak in an intensive care unit (ICU) facility in Baja California Sur, México. METHODOLOGY: Thirty-five environmental samples were collected, subsequently, disinfection with AA (4%) was performed, and two days later the same areas were sampled inside the ICU facility. Carbapenem-resistant A. baumannii (CRAB) was detected with loop-mediated isothermal amplification assay (Garciglia-Mercado et al. companion paper), targeting blaOXA-23-like, blaOXA-24-like, blaOXA-51-like, blaOXA-58-like, blaIMP and blaVIM genes. CRAB isolates before and after disinfection were compared by PFGE. RESULTS: Eighteen (54.5%) and five (14.3%) of thirty-five environmental samples were identified as Acinetobacter baumannii before and after disinfection, respectively, showing a significant decrease of 85.7% (p < 0.05) both by Loop-mediated isothermal amplification (LAMP) and polymerase chain reaction (PCR). Furthermore, the presence of blaOXA-23-like and blaOXA-58-like genes significantly decreased (p < 0.05) both by LAMP and PCR methods. PFGE genotype showed high similarity among CRAB isolates before and after disinfection, suggesting wide clonal dissemination in the ICU facility. CONCLUSIONS: This study demonstrated the novel application of AA with the LAMP assays developed for detecting CRAB. AA promises to be a cheap and efficacious disinfectant alternative to both developed and especially developing countries, preventing the spread of this organism in the environment and to other susceptible patients in health care settings.

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Cetacea is a clade well-adapted to the aquatic lifestyle, with diverse adaptations and physiological responses, as well as a robust antioxidant defense system. Serious injuries caused by boats and fishing nets are common in bottlenose dolphins (Tursiops truncatus); however, these animals do not show signs of serious infections. Evidence suggests an adaptive response to tissue damage and associated infections in cetaceans. Heme oxygenase (HO) is a cytoprotective protein that participates in the anti-inflammatory response. HO catalyzes the first step in the oxidative degradation of the heme group. Various stimuli, including inflammatory mediators, regulate the inducible HO-1 isoform. This study aims to characterize HO-1 of the bottlenose dolphin in silico and compare its structure to the terrestrial mammal protein. Upstream HO-1 sequence of the bottlenose dolphin was obtained from NCBI and Ensemble databases, and the gene structure was determined using bioinformatics tools. Five exons and four introns were identified, and proximal regulatory elements were detected in the upstream region. The presence of 10 α-helices, three 310 helices, the heme group lodged between the proximal and distal helices, and a histidine-25 in the proximal helix serving as a ligand to the heme group were inferred for T. truncatus. Amino acid sequence alignment suggests HO-1 is a conserved protein. The HO-1 "fingerprint" and histidine-25 appear to be fully conserved among all species analyzed. Evidence of positive selection within an α-helix configuration without changes in protein configuration and evidence of purifying selection were found, indicating evolutionary conservation of the coding sequence structure.

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Total mercury concentrations ([THg]) in muscle were determined in commercial finfish and elasmobranchs from Baja California Sur (BCS), Mexico to evaluate dietary Hg exposure for BCS communities, including the relationship of trophic ecology, length and mass with [THg] that might drive future consumption advice (e.g., recommend limited consumption of large fish for some species). The [THg] ranged from 0.06 to 528.02 µg kg-1 ww in finfish and 17.68-848.26 µg kg-1 ww in elasmobranchs. Relative to the consumption threshold set for predatory fish in Mexico, all species had a concentration below 1000 µg kg-1 ww. As expected, 16 (4.02%) and 75 (18.84%) individual fish were above advisory thresholds of 500 and 200 µg kg-1 ww, respectively. The hazard quotients (HQs) in most species were significantly <1.0, only banded guitarfish showed a significant median HQ > 1.0. Thus, the relative level of risk of high Hg exposure is low for most species.

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INTRODUCTION: Carbapenem-resistant A. baumannii (CRAB) represents a public health threat increasing worldwide. We assess the suitability of a loop-mediated isothermal amplification (LAMP) method for on-site screening of CRAB in a hospital facility. METHODOLOGY: A set of six primers were designed for recognizing eight distinct sequences on six targets: blaOXA-23-like, blaOXA-24-like, blaOXA-51-like, blaOXA-58-like, blaIMP, and blaVIM. A LAMP method was developed, optimized and evaluated for the identification of CRAB in thirty-three environmental samples from an outbreak in an Intensive Care Unit (ICU) facility. RESULTS: The sensitivity of the LAMP assay for the detection of A. baumannii was ten-fold higher than the PCR assay (1.0 ng.µL-1). The LAMP assays showed a higher detection rate for CRAB samples and robust diagnosis performance in comparison to a conventional PCR, with clinical sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 100% for blaOXA-23-like, blaOXA-51-like and blaVIM. CONCLUSIONS: The developed LAMP assays are powerful tools that can be useful in on-site screening of CRAB causing local outbreaks in clinics and hospitals facilities where costs and equipment restraints are imperative.

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Cadmium (Cd) occurs naturally; however, its concentration can increase with anthropogenic activities. Excess Cd increases reactive oxygen species (ROS) production and oxidative damage, which can lead to pathological conditions. Marine mammals accumulate Cd in the liver and the kidney; yet, there are no reports of Cd-associated tissue damage in whales, seals or dolphins. Response to Cd exposure (0-5.0 µM CdCl2 for 1-12 h) was analyzed and compared in primary skeletal muscle cells isolated from northern elephant seals (Mirounga angustirostris) and humans (Homo sapiens). Antioxidant enzyme activities (glutathione S-transferase, glutathione reductase, glutathione peroxidase), glutathione concentration, and protein carbonyl levels (an indicator of oxidative damage) were quantified. Glutathione levels were higher in northern elephant seal than in human cells. Protein carbonyl content in cells exposed to Cd was lower and had a smaller variability range in elephant seals than in humans. Generalized linear models (GLIM) identified Cd exposure and antioxidant defenses as significant contributors to protein carbonyl variability in human but not in elephant seal cells. These results suggest that the previously observed differences in circulating and tissue glutathione levels between marine and terrestrial mammals are maintained under cell culture conditions and that northern elephant seal and human muscle cells respond differently to Cd exposure. The results also suggest that the observed differences could potentially be associated with the protective mechanisms that allow northern elephant seals to tolerate extreme conditions that result in increased ROS generation (e.g. diving, sleep apnea, fasting) with no oxidative damage.

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