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Abstract: An inverse and unusual relationship was found between preferred temperature and acclimation temperature in the bullseye puffer, Sphoeroides annulatus. The final preferendum temperature (PT) was 26.8°C. The critical thermal maxima (CTMax) were 37.7, 38.8, 40.0, 40.8 and 41.3°C where the temperatures of acclimation were 19, 22, 25, 28 and 31°C±1°C, respectively, and the endpoint of CTMax was loss of the righting response. The acclimation response ratio presented an interval of 0.22–0.38; these values are in agreement with results for other subtropical and tropical fishes. The temperature significantly affected the oxygen consumption of bullseye puffer juveniles. The oxygen consumption rate (OCR) increased significantly with an increment in the temperature from 19 to 31°C. The range of the temperature coefficient Q 10 in bullseye puffer individuals was lowest between 25 and 28°C, at 1.37. The optimal temperature for growth was 26°C. The results of this study will be useful for optimizing the culture of bullseye puffer juveniles in controlled conditions. [Copyright &y& Elsevier]

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Ocean warming is expected to occur due to anthropogenic climate change bringing a spatial shift of marine communities. Experimental data that characterize the aerobic power budget via an aerobic scope, thermal metabolic scope, or thermal preferences have been proposed as tools that can describe species distribution since they characterize species fitness or performance under different temperatures. This study tested the potential relationship between observed occurrences and different physiological studies in the Americas for 11 commercially important species in Mexico. Projections were also developed for Mexico's exclusive economic zone under different climate warming scenarios. The physiological data were fitted from optimum up to pejus temperatures and projected to sea surface temperatures for present (2003–2014) and Representative Concentration Pathway (RCP) scenarios (RCP 2.6, RCP 4.5, RCP 6.0, and RCP 8.5) for the period 2040–2050 and 2090–2100. For species with wide distributions in the Americas, the number of occurrences reported decreases at higher latitudes related to the decrease in species performance calculated from laboratory experiments. In addition, higher species occurrences are usually reported around optimum temperatures. Overall, the results suggest that pejus temperatures likely restrict latitudinal distribution, at least for widely distributed taxons. Regarding Mexican projections, the results varied widely by species. For example, in the Atlantic Ocean, Octopus maya and Panulirus argus are vulnerable to warming scenarios, while Centropomus undecimalis is not. Interestingly, northern Campeche Bank, the Gulf of California, and Western Baja California may act as thermal refugia for marine species indicating they could be assigned as protected areas to support fisheries throughout the Mexican exclusive economic zone. This research adds to the increasing evidence of the relationship between thermal niche and wild population distribution. • Thermal niche estimated from physiological studies scales latitudinally with species occurrence. • Species occurrence aggregate around optimal temperatures. • Pejus temperatures tend to delimitate species distribution latitudinally. • It was noted that vulnerable species could use upwelling zone in Mexico as thermal refugia. [ABSTRACT FROM AUTHOR]

Interest in mariculture of the lion's paw scallop, Nodipecten subnodosus, is increasing due to the overexploitation of wild populations in Mexico and the species' high market demand. Four larval and three postlarval trials of N. subnodosus were carried out using batch- or flow-through culture in 500-L tanks in the laboratory to test the variability of the culture methodology in terms of percent survival (S) and growth. Temporal changes in weight and energy substrates (proteins, lipids and carbohydrates) were also assessed during larval development. The larval period of N. subnodosus fed with a binary algal diet lasted 12 to 15 days at 26 °C. Maximal S to metamorphosis was 19 to 22%. Higher larval growth rate was observed in trials where larvae were fed higher amounts of microalgae in both batch (10.1 μm d−1) and flow-through (9.7 μm d) systems. Postlarvae exhibited up to an order of magnitude higher shell gross growth rate (GGR) than larvae, and differences in total yield appeared to be related to the amount of food. Total dry weight, ash-free dry weight, proteins, and lipids decreased significantly in D-stage larvae and increased thereafter, reaching new maximal values in pediveligers. Combined results suggest that N. subnodosus larvae stocked at high densities (10 to 20 larvae mL−1) in batch and flow-through culture can reach high growth rates when fed sufficient amounts of high-quality algae. The latter method also allowed to substantially increase the stocking larval/postlarval density without compromising larval growth or postlarval yield. Larval biochemical patterns indicated that D-stage larvae growth and survival were heavily dependent on protein/lipid egg reserves. Accumulation patterns in umboned-pediveliger stages also suggest that metamorphosis relied on protein-lipid metabolism. • Flow-through (FL) and batch culture of Nodipecten subnodosus larvae/postlarvae were compared. • Maximal larval growth rates (10 μm d−1) were attained in FL even at 20 larvae mL−1. • Postlarvae showed as much as 10-fold acceleration in growth rate (40 to 73 μm d−1). • Survival of D-stage larvae was dependent on maternally-derived energy reserves. • Endogenous protein and lipids accumulate from umbonate through pediveliger stages. [ABSTRACT FROM AUTHOR]

Species are expected to migrate to higher latitudes as warming intensifies due to anthropogenic climate change since physiological mechanisms have been adapted to maximize fitness under specific temperatures. However, literature suggests that upwellings could act as thermal refugia under climate warming protecting marine ecosystem diversity. This research aimed to predict the effects of climate warming on commercial and non-commercial fish species reported in official Mexican documents (>200 species) based on their thermal niche to observe if upwellings can act as potential thermal refugia. Present (2000-2014) and Representative Concentration Pathway (6.0 and 8.5) scenarios (2040-2050 and 2090-2100) have been considered for this work. Current and future suitability patterns, species distribution, richness, and turnover were calculated using the minimum volume ellipsoids as algorithm. The results in this study highlight that beyond migration to higher latitudes, upwelling regions could protect marine fishes, although the mechanism differed between the innate characteristics of upwellings. Most modeled species (primarily tropical fishes) found refuge in the tropical upwelling in Northern Yucatan. However, the highest warming scenario overwhelmed this region. In contrast, the Baja California region lies within the Eastern Boundary Upwelling Systems. While the area experiences an increase in suitability, the northern regions have a higher upwelling intensity acting as environmental barriers for many tropical species. Conversely, in the southern regions where upwelling is weaker, species tend to congregate and persist even during elevated warming, according to the turnover analysis. These findings suggest that tropicalization in higher latitudes may not be as straightforward as previously assumed. Nevertheless, climate change affects numerous ecosystem features, such as trophic relationships, phenology, and other environmental variables not considered here. In addition, uncertainty still exists about the assumption of increasing intensity of upwelling systems., Competing Interests: Declaration of competing interest The authors report no potential competing interests., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Ankylosing spondylitis (AS) is a type of inflammatory arthritis that affects primarily the spine. There is a strong association of the HLA-B*27 allele with AS pathogenesis, but recent studies have demonstrated the participation of ERAP1 gene in the genetic susceptibility. The aim of this study was to determine whether HLA-B tag-single nucleotide polymorphisms (SNPs) and ERAP1-related genetic variations associated with AS have equal or similarly performance in patients´ screening compared to HLA-B*27 standard genotyping in Mexican population., Methods and Results: Genomic DNA from patients with AS and population-based controls from Mexico City was analyzed for five single nucleotide polymorphisms (SNPs): rs4349859, rs13202464, rs116488202, tagging HLA-B*27; and rs30187 and rs27044 in ERAP1 gene. TaqMan genotype assay method was used for SNPs genotyping. We found a significant association between AS and the heterozygote genotypes and minor alleles of the HLA-B*27 tag-SNPs, as well as for their haplotypes. With respect to ERAP1 polymorphisms, no significant associations were observed (p > 0.05). The sensitivity and specificity analysis showed values of 0.96 and 1.00 for the rs4349859 SNP, and 0.96 and 0.94 for the rs116488202 SNP, respectively, in detecting HLA-B*27 compared to the B27 test as the gold standard., Conclusions: HLA-B*27 tag-SNPs are associated with AS susceptibility; furthermore, the rs4349859 SNP by its own have an outstanding performance in detecting HLA-B*27 and therefore can be proposed as screening marker in the identification of HLA-B*27 in our population., (© 2021. The Author(s), under exclusive licence to Springer Nature B.V.)

Using data related to thermal optimal and pejus of the embryos of Octopus americanus from Brazil and O. insularis and O. maya from Mexico, this study aimed to project the potential distribution areas in the Gulf of Mexico and predict distribution shifts under different Representative Concentration Pathway scenarios (RCP 6 and 8.5) for the years 2050 and 2100. The different thermal tolerances elicited different responses to current and future scenarios. In this sense, O. insularis and O. maya thermal niches stretch from the Caribbean to Florida. Nevertheless, O. insularis may inhabit warmer areas than O. maya. Surprisingly, no area was considered thermally habitable for O. americanus, which could have been associated with the use of data of populations thermally adapted to temperate conditions south of Brazil. According to models, a warming scenario would cause a restriction of the available thermal niche of O. maya, while O. insularis could expand under RCP 6 scenarios. This restriction was more substantial in the RCP 8.5 scenario. Nevertheless, under the RCP 8.5 scenario, the temperature in 2100 may negatively affect even O. insularis, the species most thermal tolerant. If our results are accurate, the fishing yield of O. insularis will increase in the future, replacing the heavily exploited O. maya in the coasts of the southern Gulf of Mexico. Regarding O. americanus, no inference might be made until thermal tolerances of locally adapted populations can be studied., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The Cortes geoduck Panopea globosa is a large bivalve with a high commercial value distributed from the southern Pacific coast of the Baja California Peninsula to the northern Gulf of California, inhabiting a wide range of subtropical temperatures. A new record of this species in shallower waters suggests that it can tolerate a warmer environment than previously thought. To better understand the whole-body and molecular response mechanisms to different temperatures, we assessed the metabolic rate of juvenile individuals exposed to chronic and acute thermal conditions and analyzed the transcriptomic response in ctenidial tissues. Whole-body metabolic rate measurements showed that juveniles were able to acclimate at least partially within three weeks from 20 °C (C20) to 29 °C (C29), while organisms acutely exposed to 29 °C (A29) significantly increased their metabolic rate. This was coincident with transcriptomic results, as similar gene expression patterns were found in clams chronically exposed to C29 and C20, but different from those acutely exposed to 29 °C (A29) and 31 °C (A31). High degree of expression of genes involved in DNA repair and transcription regulation were found in C29 juveniles, whereas protective genes against oxidative stress were highly expressed in A29 organisms. A high expression of genes involved in protein re-folding was also observed in A31 juveniles. In conclusion, the combined results of whole-body metabolism and transcriptomic expression patterns suggest that P. globosa juveniles have a high physiological plasticity and are well adapted to inhabit an environment with broad temperature fluctuations., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Pollution by heavy metals in marine ecosystems in the Gulf of Mexico is one of the hardest conservation issues to solve. Sharks as top predators are bioindicators of the marine ecosystem health, since they tend to bioaccumulate and biomagnify contaminants; they also represent a food source for local consumption. Thus, the objective of this study was to study the possible presence of heavy metals and a metalloid in livers of Carcharhinus limbatus. For this, a total of 19 shark livers were taken from animals captured nearby Tamihua, Veracruz, Mexico from December 2007 to April 2008. 12 out of the 19 captured sharks were males, one was an adult female, three were juvenile males, and three juvenile females. Four heavy metals (Hg, Pb, Cd, and Cr) and one metaloid (As) were analyzed in shark livers using an atomic absorption spectrophotometry with flame and hydride generator. Our results showed that the maximum concentrations found were: Hg = 0.69 mg/kg, Cd = 0.43 mg/kg, As = 27.37 mg/kg, Cr = 0.70 mg/kg. The minimum concentrations found were: As = 14.91 mg/kg, Cr = 0.35 mg/kg. The Pb could not be determined because the samples did not have the spectrophotometer minimum detectable amount (0.1 mg/kg). None of the 19 samples analyzed showed above the permissible limits established by Mexican and American laws. There was a correlation between shark size and Cr and As concentration (Pearson test). The concentration of Cr and As was observed to be higher in bigger animals. There was not a significant difference in heavy metals concentration between juveniles and adults; however, there was a difference between males and females. A higher Cr concentration was found in females when compared to males. None of the samples exceed the maximum limit established by the laws of Mexico and the United States of America. Much longer studies are needed with C. limbatus and other species caught in the region, in order to determine the degree of contaminants exposure in aquatic ecosystems and to identify potential health risks to consumers.

Objective: We present a retrospective review of urological complications following kidney transplantation in two medical centers in the Mexican state of Veracruz using Lich-Gregoir extravesical ureteroneocystostomy during a 4-year period., Methods: Records from 242 patients from January 2003 to November 2007 were reviewed. Standard technique for organ procurement, open nephrectomy and kidney transplant was performed. EVU was used in all patients. Urological complications and management are reported., Results: There were 19 complications recorded in 18 patients (7.8%). Sixteen kidneys were obtained from living donors. Urinary leak was the most common complication (4.5%) followed by ureteral stenosis (1.6%), vesicoureteral reflux (1.2%) and ureteral necrosis (0.4%) Most patients were treated with Foley catheter (42%), Boary flap (26%) and nephrostomy (15%); 1.23% grafts were lost associated with urological complications., Conclusions: Renal transplantation should incur few urological complications. Attention to technical details should be paid to avoid major complications. Early evaluation to correct complications reduces sepsis, morbidity and the risk of losing graft function.

Background: Clinical, histological, and more recently, molecular factors have been described as important in survival of the patient with medulloblastoma. Best survival results include aggressive chemotherapeutic protocols. More exact risk analysis may differentiate patients who require aggressive treatments from those with low risk who may respond adequately to less aggressive protocols., Methods: Twenty six patients were included over a 10-year period and were followed for at least 5 years. Personal variables were obtained from their clinical records. Immunochemistry studies were performed on their formalin-fixed paraffin-embedded tissues. Statistical analysis included chi(2) test, odds risk, linear regression models, and Kaplan-Meier survival analysis., Results: Metastatic disease and chemotherapy with VP16-carboplatin reduce the patient's probability of survival, whereas anaplastic histology increases the probability of death. Global survival and disease-free survival were 66.6 and 45.02%, respectively. Only two patients overexpressed the ERBB2 protein, and no significant difference was found in survival in terms of ERBB2 overexpression., Conclusions: Risk stratification has become very important in medulloblastoma. We found an increased hazard of death when metastatic disease was present. Gene expression in Mexican children requires a larger sample in order to be analyzed.

Neuroblastoma (NB) is the most frequent extracranial solid tumor in children according to the literature. In Mexico it is less frequent, fallen to 8th place. Our objective was to analyze our experience and compare it with the one reported in other countries. We included all patients admitted to our hospital during the previous five years and who had not received any treatment. Patients with stages I, II, and IV received cyclophosphamide and epirrubicin. Patients with stages were III and IV received the same chemotherapy alternating with cisplatinum., ifosfamide and etoposide during 12 months as well as massive doses of 131-MIBG and surgical ablation of the remaining tumor when possible. We included 30 patients, 25 with initial presentation in the abdomen. Five were in early stages and 20 (70%) were advanced with an overall survival of 100% and 27% at 5 years respectively. When analyzed by age, 40% were 12 months of age and 60% older, with survival of 100% and 27% in the same period, respectively. According to histology there was 91% survival for differentiated and 23% for undifferentiated tumors. The chemotherapeutic regimen reported is effective but not better than that reported by other authors, in which some benefits are seen with use of transplant and immunotherapy. The most important prognostic factors are still considered to be age, stage and histology.