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Copyright of DYNA - Ingeniería e Industria is the property of Publicaciones Dyna SL and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Diabetic peripheral neuropathy (DPN) is the most common complication of type 2 diabetes mellitus (T2DM); its diagnosis and treatment are based on symptomatic improvement. However, as pharmacological therapy causes multiple adverse effects, the implementation of acupunctural techniques, such as electroacupuncture (EA) has been suggested as an alternative treatment. Nonetheless, there is a lack of scientific evidence, and its mechanisms are still unclear. We present the design and methodology of a new clinical randomized trial, that investigates the effectiveness of EA for the treatment of DPN., Methods: This study is a four-armed, randomized, controlled, multicenter clinical trial (20-week intervention period, plus 12 weeks of follow-up after concluding intervention). A total of 48 T2DM patients with clinical signs and symptoms of DPN; and electrophysiological signs in the Nerve Conduction Study (NCS); will be treated by acupuncture specialists in outpatient units in Mexico City. Patients will be randomized in a 1:1 ratio to one of the following four groups: (a) short fibre DPN with EA, (b) short fibre DPN with sham EA, (c) axonal DPN with EA and (d) axonal DPN with sham EA treatment. The intervention will consist of 32 sessions, 20 min each, per patient over two cycles of intervention of 8 weeks each and a mid-term rest period of 4 weeks. The primary outcome will be NCS parameters, and secondary outcomes will include DPN-related symptoms and pain by Michigan Neuropathy Screening Instrument (MNSI), Michigan Diabetic Neuropathy Score (MDNS), Dolour Neuropatique Score (DN-4), Semmes-Westein monofilament, Numerical Rating Scale (NRS) for pain assessment, and the 36-item Short Form Health Survey (SF-36). To measure quality of life and improve oxidative stress, the inflammatory response; and genetic expression; will be analysed at the beginning and at the end of treatment., Discussion: This study will be conducted to compare the efficacy of EA versus sham EA combined with conventional diabetic and neuropathic treatments if needed. EA may improve NCS, neuropathic pain and symptoms, oxidative stress, inflammatory response, and genetic expression, and it could be considered a potential coadjutant treatment for the management of DPN with a possible remyelinating effect., Trial Registration: ClinicalTrials.gov. NCT05521737 Registered on 30 August 2022. International Clinical Trials Registry Platform (ICTRP) ISRCTN97391213 Registered on 26 September 2022 [2b]., (© 2024. The Author(s).)

In Mexico, 1 out of 3 schoolchildren aged 5 to 11 years is overweight or obese, which represents one of the main public health concerns, due to the fact that this condition in the child population is highly associated with the development of metabolic complications in adults. To date, dietary and physical activity interventions to prevent this problem have shown modest results worldwide. Biomedical studies in Mexico have shown that the pathophysiology of childhood overweight and obesity presents different molecular patterns, inflammation and oxidative stress, possibly associated with specific variants in the genome. However, the challenge is to achieve a secure characterization of this evidence so that it can be used in intervention studies aimed to improve the ability to predict and treat childhood overweight and obesity in Mexico. The biomedical challenge is to make knowledge a prevention strategy in families, in society and in the country, in order to fight the serious problem of obesity and its consequences., (Licencia CC 4.0 (BY-NC-ND) © 2024 Revista Médica del Instituto Mexicano del Seguro Social.)

Gamete size variation between the sexes is central to the concept of sex roles, however, to what extent gamete size variation within the sexes relates to sex role variation remains unclear. Comparative and theoretical studies suggest that, when clutch size is invariable, polyandry is linked to a reduction of egg size, while increased female-female competition for mates favors early breeding when females cannot monopolize multiple males. To understand whether and how breeding phenology, egg size, and mating behavior are related at the individual level, we studied the reproductive histories of 424 snowy plover females observed in the wild over a 15-year period. Egg size, but not polyandry, were highly repeatable for individual females. Consistent with theoretical predictions, we found that polyandrous females were the earliest breeders and that early clutches contained smaller eggs than clutches initiated later. Neither egg size nor mating behavior showed clear signs of an age-related deterioration, on the contrary, prior experience acquired either through age or local recruitment enabled females to nest early. Taken together, these results suggest that gamete size variation is not linked to mating behavior at the individual level, and, consequently, the adaptive potential of such variation appears to be limited., (© The Author(s) 2023. Published by Oxford University Press on behalf of The Society for the Study of Evolution (SSE).)

Worldwide, Mexico is one of the countries with the highest rate of obesity, which is a condition considered the main risk factor for type 2 diabetes. Among the mechanisms that predispose to obesity, the interaction between food intake and genetic components has been little explored. Recently we evidenced a significant association between the copy number (CN) of AMY1A and AMY2A genes, the enzymatic activity of salivary and pancreatic amylase, and the frequency of childhood obesity in Mexico, a particular population due to the high consumption of starch in the diet and the high prevalence of obesity in children and adults. This review aims to find a better understanding of the role of amylase in obesity through a description of the evolution of the CN of its genes, the association of its enzymatic activity with obesity, and the effect of its interaction with starch intake on Mexican children. In addition, it denotes the importance of the experimental perspectives of further investigation regarding the mechanism by which amylase could regulate the abundance of oligosaccharide-fermenting bacteria and producers of short-chain fatty acids and/or branched-chain amino acids that could contribute to the alteration of the physiological processes associated with intestinal inflammation and metabolic deregulation that predispose to the development of obesity., (© 2023 Revista Médica del Instituto Mexicano del Seguro Social.)

Objective: To evaluate hypothalamic-pi- tuitary-gonadal (HPG) axis alterations at 1 and 12 months after kidney transplan- tation (KT) and their association with in- sulin resistance., Methods: A retrospective clinical study was conducted in a tertiary care center in kidney transplantation recipients (KTRs) aged 18- 50 years with primary kidney disease and stable renal graft function. LH, FSH, E2/T, and HOMA-IR were assessed at 1 and 12 months after KT., Results: Twenty-five KTRs were included; 53% were men, and the mean age was 30.6±7.7 years. BMI was 22.3 (20.4-24.6) kg/m2, and 36% had hypogonadism at 1 month vs 8% at 12 months (p=0.001). Re- mission of hypogonadism was observed in all men, while in women, hypogonadotropic hypogonadism persisted in two KTRs at 12 months. A positive correlation between go- nadotrophins and age at 1 and 12 months was evident. Fifty-six percent of patients had insulin resistance (IR) at 1 month and 36% at 12 months (p=0.256). HOMA-IR showed a negative correlation with E2 (r=- 0.60; p=0.050) and T (r=-0.709; p=0.049) at 1 month, with no correlation at 12 months. HOMA-IR at 12 months after KT correlated positively with BMI (r=0.52; p=0.011) and tacrolimus dose (r=0.53; p=0.016)., Conclusion: Successful KT restores the HPG axis in the first year. Hypogonadism had a negative correlation with IR in the early pe- riod after KT, but it was not significant at 12 months.

The prevalence of type 2 diabetes (T2D) in Mexico is 14.4%. This disease is characterized by a state of hyperglycemia and chronic inflammation secondary to inadequate insulin secretion and its resistance. Among its risk factors for metabolic diseases development, the interaction between obesity, sedentary lifestyle, hypercaloric diets and genetic variants play an important role. For decades, different basic and applied research groups have worked in an interdisciplinary way to provide scientific evidence that has helped to understand the mechanisms involved in the pathophysiology of T2D in Mexicans. However, today the urgency of the advance and better proposals for prevention and management of patients with T2D makes it necessary to use translational medicine, which integrates scientific knowledge with the use of innovative technologies to provide comprehensive health care. In this sense, the present document concisely describes, with a translational approach, the implications of the interaction of environmental and genetic risk factors in the development of childhood obesity and T2D in Mexico.

Background: Intimate partner violence (IPV) is one of the most prevalent forms of violence against women globally and it is considered a public health problem. Because the experience of IPV is stressful and traumatic for victims, they are at high risk of developing alteration of the Hypothalamus-Pituitary-Adrenal (HPA) axis functioning as well as anxiety and depression symptoms. The aim of this study was to compare the quality of life and changes in cortisol response to an acute stressor between women exposed to IPV and non-exposed women. Differences according to symptoms of anxiety and depression including the risk of suicide thoughts, were also analyzed., Method: Our sample size consisted of 130 women (ages 18-68) grouped as follows: 71 women experiencing IPV and 59 women without history of IPV as control group. All participants completed a battery of questionnaires including IPV exposure, anxiety, and depression symptoms (Beck Inventories), as well as quality of life (WHOQOL-BREF). Salivary cortisol levels in response to a cognitive test with verbal, mathematical, and abstract reasoning were measured at four time points., Results: Women exposed to IPV, with severe anxiety and depression symptoms as well as suicide thoughts, exhibited heightened cortisol response after the cognitive test and reported lower quality of life compared to (i) women experiencing IPV with moderate symptoms of anxiety and depression, who showed a blunted response, and (ii) women without history of IPV with minimal to moderate symptoms, who showed a decreased cortisol profile. Social relationships dimension was in particular the most affected aspect of quality of life., Conclusions: Our findings highlight the role of cortisol responses as a complementary biological marker to be associated with severe psychiatric disturbances in women exposed to IPV., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Cerda-De la O, Cerda-Molina, Mayagoitia-Novales, de la Cruz-López, Biagini-Alarcón, Hernández-Zúñiga, Borráz-León and Whaley-Sánchez.)

The endoplasmic reticulum is an abundant, dynamic and energy-sensing organelle. Its abundant membranes, rough and smooth, are distributed in different proportions depending on the cell lineage and requirement. Its function is to carry out protein and lipid synthesis, and it is the main intracellular Ca2+ store. Caloric overload and glycolipotoxicity generated by hypercaloric diets cause alteration of the endoplasmic reticulum, activating the Unfolded Protein Response (UPR) as a reaction to cellular stress related to the endoplasmic reticulum and whose objective is to restore the homeostasis of the organelle by decreasing oxidative stress, protein synthesis and Ca2+ leakage. However, during chronic stress, the UPR induces reactive oxygen species formation, inflammation and apoptosis, exacerbating the state of the endoplasmic reticulum and propagating a deleterious effect on the other organelles. This is why endoplasmic reticulum stress has been considered an inducer of the onset and development of metabolic diseases, including the aggravation of COVID-19. So far, few strategies exist to reestablish endoplasmic reticulum homeostasis, which are targeted to sensors that trigger UPR. Therefore, the identification of new mechanisms and novel therapies related to mitigating the impact of endoplasmic reticulum stress and associated complications is urgently warranted., (© 2022 Revista Medica del Instituto Mexicano del Seguro Social.)

Objective: To determine the most frequent dermatoses in patients with kidney transplant in the dermatology consultation, Hospital de Especialidades, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, in Mexico City, in the period from March 2016 to March 2020., Method: Descriptive, cross-sectional study that included 153 patients with a complete medical history with prior informed consent and authorization from the hospital ethics committee., Results: All patients presented one or more dermatoses. The most frequent were infectious (mycosis, viral) and, in decreasing order, other dermatoses (keratosis pilaris, melasma), tumorous (benign), inflammatory (seborrheic dermatitis, eczema), probably secondary to drugs and autoimmune (alopecia areata)., Conclusions: All kidney transplant patients presented at least one dermatosis, predominantly those of infectious origin. We recommend dermatological evaluation prior to transplantation for timely diagnosis and treatment of dermatoses that could increase the morbi-mortality of patients., (Copyright: © 2022 Permanyer.)

Objective: To determine the evolution, associated factors and the outcomes of transplanted people one year after the evolution of a cohort in Mexico., Method: Kidney transplant cohort from 2013 to 2017 in Mexico. 1118 patients were analyzed. Five outcomes were studied: overall survival, kidney graft, patient survival, delayed function, and acute dysfunction. Kaplan-Meier was used for kidney graft survival. For risk, bivariate and multivariate analyzes were performed with a significant value of p < 0.05., Results: Of the 1118 kidney transplant patients, 57 (5.09%) had kidney graft loss, 52 (4.65%) died during the one-year follow-up; survival of the patient of 95.35% and of the graft 90.25%., Conclusions: The risk factors for the outcomes were transplantation from a deceased donor, recipient over 50 years of age and use of polyclonal agents. Infections and age are related to the death of the patient., (Copyright: © 2022 Permanyer.)

When individuals breed more than once, parents are faced with the choice of whether to re-mate with their old partner or divorce and select a new mate. Evolutionary theory predicts that, following successful reproduction with a given partner, that partner should be retained for future reproduction. However, recent work in a polygamous bird, has instead indicated that successful parents divorced more often than failed breeders (Halimubieke et al. in Ecol Evol 9:10734-10745, 2019), because one parent can benefit by mating with a new partner and reproducing shortly after divorce. Here we investigate whether successful breeding predicts divorce using data from 14 well-monitored populations of plovers (Charadrius spp.). We show that successful nesting leads to divorce, whereas nest failure leads to retention of the mate for follow-up breeding. Plovers that divorced their partners and simultaneously deserted their broods produced more offspring within a season than parents that retained their mate. Our work provides a counterpoint to theoretical expectations that divorce is triggered by low reproductive success, and supports adaptive explanations of divorce as a strategy to improve individual reproductive success. In addition, we show that temperature may modulate these costs and benefits, and contribute to dynamic variation in patterns of divorce across plover breeding systems.

Background: Understanding the structure and variability of adaptive loci such as the major histocompatibility complex (MHC) genes is a primary research goal for evolutionary and conservation genetics. Typically, classical MHC genes show high polymorphism and are under strong balancing selection, as their products trigger the adaptive immune response in vertebrates. Here, we assess the allelic diversity and patterns of selection for MHC class I and class II loci in a threatened shorebird with highly flexible mating and parental care behaviour, the Snowy Plover (Charadrius nivosus) across its broad geographic range., Results: We determined the allelic and nucleotide diversity for MHC class I and class II genes using samples of 250 individuals from eight breeding population of Snowy Plovers. We found 40 alleles at MHC class I and six alleles at MHC class II, with individuals carrying two to seven different alleles (mean 3.70) at MHC class I and up to two alleles (mean 1.45) at MHC class II. Diversity was higher in the peptide-binding region, which suggests balancing selection. The MHC class I locus showed stronger signatures of both positive and negative selection than the MHC class II locus. Most alleles were present in more than one population. If present, private alleles generally occurred at very low frequencies in each population, except for the private alleles of MHC class I in one island population (Puerto Rico, lineage tenuirostris)., Conclusion: Snowy Plovers exhibited an intermediate level of diversity at the MHC, similar to that reported in other Charadriiformes. The differences found in the patterns of selection between the class I and II loci are consistent with the hypothesis that different mechanisms shape the sequence evolution of MHC class I and class II genes. The rarity of private alleles across populations is consistent with high natal and breeding dispersal and the low genetic structure previously observed at neutral genetic markers in this species.

Shorebirds (part of the order Charadriiformes) have a global distribution and exhibit remarkable variation in ecological and behavioural traits that are pertinent to many core questions in the fields of evolutionary ecology and conservation biology. Shorebirds are also relatively convenient to study in the wild as they are ground nesting and often occupy open habitats that are tractable to monitor. Here we present a database documenting the reproductive ecology of 1,647 individually marked snowy plovers (Charadrius nivosus) monitored between 2006 and 2016 at Bahía de Ceuta (23°54N, 106°57W) - an important breeding site in north-western Mexico. The database encompasses various morphological, behavioural, and fitness-related traits of males and females along with spatial and temporal population dynamics. This open resource will serve as an important data repository for addressing overarching questions in avian ecology and wetland conservation during an era of big data and global collaborative science.

Bone mineral metabolism disease, which included persistent hyperparathyroidism, is common after successful kidney transplantation (KT) and is related with negative outcomes in kidney transplant recipients. There is a lack of information about bone mineral metabolism, persistent hyperparathyroidism, and its risk factors in Latin kidney transplant recipients (KTRs). Material and Methods : A retrospective study was conducted in 74 patients aged 18-50 years with evolution of 12 months after KT and estimated glomerular filtration rate (eGFR) >60 ml/min; biochemical data of bone mineral metabolism before and at 1, 3, 6, and 12 months of KT were registered. Results. Age was 33 (IQR 27-37) years; 54% ( n  = 40) were men. Before KT, all patients had hyperparathyroidism, 40% ( n  = 30) hypocalcemia, 86% ( n  = 64) hyperphosphatemia, and 42% ( n  = 31) hyperphosphatasemia. After KT, an increase of calcium and a diminution of PTH, phosphorus, and alkaline phosphatase were corroborated ( p =0.001). All patients had hypovitaminosis D (deficiency: 91% ( n  = 67); insufficiency: 9% ( n  = 7)); 40% ( n  = 30) had persistent hyperparathyroidism at 12 months. Hyperphosphatasemia before KT (OR = 4.17 (95% CI: 1.21-14.44); p =0.04), hyperparathyroidism at 6 months (OR = 1.84 (95% CI; 1.67-2.06); p =0.02), hypovitaminosis D at 6 months (OR = 3.94 (95% CI: 1.86-17.9); p =0.01), and hyperphosphatasemia at 6 months (OR = 1.47 (95% CI: 1.07-2.86); p =0.03) were risk factors for persistent hyperparathyroidism at 12 months after KT. Conclusion . Persistent hyperparathyroidism at 6 months, hypovitaminosis D, and hyperphosphatasemia are risk factors for persistent hyperparathyroidism at 1 year of KT in Latin population., Competing Interests: The authors declare that there are no conflicts of interest regarding the publication of this article., (Copyright © 2020 Lourdes Balcázar-Hernández et al.)

Social monogamy has evolved multiple times and is particularly common in birds. However, it is not well understood why some species live in long-lasting monogamous partnerships while others change mates between breeding attempts. Here, we investigate mate fidelity in a sequential polygamous shorebird, the snowy plover ( Charadrius nivosus ), a species in which both males and females may have several breeding attempts within a breeding season with the same or different mates. Using 6 years of data from a well-monitored population in Bahía de Ceuta, Mexico, we investigated predictors and fitness implications of mate fidelity both within and between years. We show that in order to maximize reproductive success within a season, individuals divorce after successful nesting and re-mate with the same partner after nest failure. Therefore, divorced plovers, counterintuitively, achieve higher reproductive success than individuals that retain their mate. We also show that different mating decisions between sexes predict different breeding dispersal patterns. Taken together, our findings imply that divorce is an adaptive strategy to improve reproductive success in a stochastic environment. Understanding mate fidelity is important for the evolution of monogamy and polygamy, and these mating behaviors have implications for reproductive success and population productivity., Competing Interests: We have no conflict of interest to declare., (© 2019 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.)

Background: Marine and intertidal organisms face the rhythmic environmental changes induced by tides. The large amplitude of spring tides that occur around full and new moon may threaten nests of ground-nesting birds. These birds face a trade-off between ensuring nest safety from tidal flooding and nesting near the waterline to provide their newly hatched offspring with suitable foraging opportunities. The semi-lunar periodicity of spring tides may enable birds to schedule nest initiation adaptively, for example, by initiating nests around tidal peaks when the water line reaches the farthest into the intertidal habitat. We examined the impact of semi-lunar tidal changes on the phenology of nest flooding and nest initiation in Snowy Plovers ( Charadrius nivosus ) breeding at Bahía de Ceuta, a coastal wetland in Northwest Mexico., Results: Using nest initiations and fates of 752 nests monitored over ten years we found that the laying season coincides with the lowest spring tides of the year and only 6% of all nests were flooded by tides. Tidal nest flooding varied substantially over time. First, flooding was the primary cause of nest failures in two of the ten seasons indicating high between-season stochasticity. Second, nests were flooded almost exclusively during the second half of the laying season. Third, nest flooding was associated with the semi-lunar spring tide cycle as nests initiated around spring tide had a lower risk of being flooded than nests initiated at other times. Following the spring tide rhythm, plovers appeared to adapt to this risk of flooding with nest initiation rates highest around spring tides and lowest around neap tides., Conclusions: Snowy Plovers appear generally well adapted to the risk of nest flooding by spring tides. Our results are in line with other studies showing that intertidal organisms have evolved adaptive responses to predictable rhythmic tidal changes but these adaptations do not prevent occasional catastrophic losses caused by stochastic events., Competing Interests: Competing interestsThe authors declare that they have no competing interests.

Introduction: Mexico has reported in 2016 a combined prevalence of obesity and overweight of 33.2% in children. The objective of this work was to make a literature review of the factors associated with obesity in Mexican children, such as genetic factors, feeding patterns, sedentary lifestyle and gut microbiota. We found that in Mexican children SNP (single nucleotide polymorphism) is present in genes such as MC4R, FTO and ADRB1, associated with obesity, and that PON-1192 polymorphism increases the risk of suffering insulin resistance. On the other hand, the variant of the ADIPOR2 gene (rs11061971) protects Mexican children against obesity, as well as a greater number of copies of the AMY gene was found in children with normal weight. The evidence of the number of copies is very important, since the current diet of the Mexican population is rich in carbohydrates and fats, origin of a nutritional transition that includes sedentary activities and a high consumption of sugary drinks. The consumption of certain foods causes important changes in the gut microbiota that contribute to the development of obesity and insulin resistance. It has been found that Mexican children with obesity have a higher abundance of phylum Firmicutes and B. eggerhii bacteria. Therefore, as obesity is so diverse, it is essential to diversify the treatment in which government authorities, parents and health authorities should get involved, as well as reinforcing nutrition and healthy eating issues in primary education in the country in order to reverse the prevalence and prevent the development of other pathologies in Mexican children.

Scientific evidence has identified that the excessive consumption of products made from high-fructose corn syrup is a trigger for obesity, whose prevalence increased in recent years. Due to the metabolic characteristics of fructose, a rapid gastric emptying is produced, altering signals of hunger-satiety and decreasing the appetite. In addition to the hepatic level during catabolism, triose phosphate is generated and adenosine triphosphate (ATP) is reduced, producing uric acid. Triose phosphate triggers the synthesis of fatty acids that increase the production and accumulation of triglycerides, diacylglycerols and ceramides that induce insulin resistance. Hyperlipidemia, insulin resistance and hyperuricemia contribute to the development of hypertension, cardiovascular disease, kidney failure, non-alcoholic fatty liver disease and some kinds of cancer. Understanding the molecular mechanisms and signaling pathways altered by the consumption of fructose is relevant to understand the development of metabolic diseases, as well as to seek therapeutic strategies to improve quality of life.

The adult sex ratio (ASR) is a fundamental concept in population biology, sexual selection, and social evolution. However, it remains unclear which demographic processes generate ASR variation and how biases in ASR in turn affect social behaviour. Here, we evaluate the demographic mechanisms shaping ASR and their potential consequences for parental cooperation using detailed survival, fecundity, and behavioural data on 6119 individuals from six wild shorebird populations exhibiting flexible parental strategies. We show that these closely related populations express strikingly different ASRs, despite having similar ecologies and life histories, and that ASR variation is largely driven by sex differences in the apparent survival of juveniles. Furthermore, families in populations with biased ASRs were predominantly tended by a single parent, suggesting that parental cooperation breaks down with unbalanced sex ratios. Taken together, our results indicate that sex biases emerging during early life have profound consequences for social behaviour.

Adult sex ratio (ASR) is a central concept in population biology and a key factor in sexual selection, but why do most demographic models ignore sex biases? Vital rates often vary between the sexes and across life history, but their relative contributions to ASR variation remain poorly understood-an essential step to evaluate sex ratio theories in the wild and inform conservation. Here, we combine structured two-sex population models with individual-based mark-recapture data from an intensively monitored polygamous population of snowy plovers. We show that a strongly male-biased ASR (0.63) is primarily driven by sex-specific survival of juveniles rather than adults or dependent offspring. This finding provides empirical support for theories of unbiased sex allocation when sex differences in survival arise after the period of parental investment. Importantly, a conventional model ignoring sex biases significantly overestimated population viability. We suggest that sex-specific population models are essential to understand the population dynamics of sexual organisms: reproduction and population growth are most sensitive to perturbations in survival of the limiting sex. Overall, our study suggests that sex-biased early survival may contribute toward mating system evolution and population persistence, with implications for both sexual selection theory and biodiversity conservation., Competing Interests: The authors declare no conflict of interest.