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Infertility is a growing worldwide public health problem, and stress is a main factor exerting detrimental effects on female reproduction. However, knowledge regarding the neuroendocrine changes caused by chronic stress in females is limited. Therefore, this study assessed the effects of stress on hormones that control female reproduction during the proestrus and diestrus stages of the estrous cycle, as well as its effects on fertility. Adult females were assigned to either a control or a stress group. Stress consisted of exposure, for 15 min, to cold-water immersion daily for 30 days. Estrous cyclicity, female sexual behavior, as well as hypothalamic kisspeptin, gonadotropin releasing hormone (GnRH) content, serum luteinizing hormone (LH), estradiol (E2), progesterone (P4), corticosterone (CORT) and fertility were assessed after chronic stress. The results show that chronically stressed females exhibited disrupted estrous cyclicity, decreased receptivity, low pregnancy rates and lower numbers of fetuses. The content of Kisspeptin and GnRH in the Anteroventral Periventricular/medial Preoptic Area decreased during proestrus, while Kisspeptin increased in the Arcuate nucleus in proestrus and diestrus. Serum LH decreased only during proestrus, whereas E2 and P4 concentrations decreased during proestrus and diestrus, with a concomitant increase in CORT levels in both stages. As a whole, these results indicate that chronic stress decreases Kisspeptin content in AVPV nucleus and GnRH in POA in females, and might induce disruption of the LH surge, consequently disrupting estrous cyclicity and fertility, leading to lower rates of pregnancy and number of fetuses.

Background The current national influenza vaccination schedule in Mexico does not recommend vaccination in the school-aged population (5–11 years). Currently, there are limited data from middle-income countries analysing the cost-effectiveness of influenza vaccination in this population. We explored the clinical effects and economic benefits of expanding the current national influenza vaccination schedule in Mexico to include the school-aged population. Methods A static 1-year model incorporating herd effect was used to assess the cost-effectiveness of expanding the current national influenza vaccination schedule of Mexico to include the school-aged population. We performed a cross-sectional epidemiological study using influenza records (2009–2018), death records (2010–2015), and discharge and hospitalisation records (2010–2016), from the databases of Mexico’s Influenza Surveillance System (SISVEFLU), the National Mortality Epidemiological and Statistical System (SEED), and the Automated Hospital Discharge System (SAEH), respectively. Cost estimates for influenza cases were based on 7 scenarios using data analysed from SISVEFLU; assumptions for clinical management of cases were defined according to Mexico’s national clinical guidelines. The primary health outcome for this study was the number of influenza cases avoided. A sensitivity analysis was performed using conservative and optimistic parameters (vaccination coverage: 30% / 70%, Vaccine effectiveness: 19% / 68%). Results It was estimated that expanding the influenza immunisation programme to cover school-aged population in Mexico over the 2018–2019 influenza season would result in 671,461 cases of influenza avoided (50% coverage and 50% effectiveness assumed). Associated with this were 262,800 fewer outpatient consultations; 154,100 fewer emergency room consultations; 97,600 fewer hospitalisations, and 15 fewer deaths. Analysis of cases avoided by age-group showed that 55.4% of them were in the school-aged population, and the decrease in outpatient consultations was largest in this population. There was an overall decrease in the economic burden for the Mexican health care system of 111.9 million US dollars; the immunization programme was determined to be cost-saving in the base, conservative and optimistic scenarios. Conclusions Vaccinating school-aged population in Mexico would be cost-effective; expansion of the current national vaccination schedule to this age group is supported.

In fighting infectious disease outbreaks, a basic epidemiological principle is to detect cases quickly and to isolate each case, to interrupt transmission. This principle has been the cornerstone of the Carso Group (CG) COVID Protocol, a systematic blueprint for the reopening of operations of workplaces in the context of ongoing disease transmission in Mexico. The CG comprises over 50 companies with approximately 180,000 employees engaged in economic activities including telecommunications, retail, construction, banking, mining, and manufacturing, among others. To cope with the COVID-19 pandemic within the CG, the Carlos Slim Foundation designed, developed and implemented MONITOR, a digital health ecosystem comprising a mobile phone application, web portal, and analytics platform, to assess the infection risk of each employee, follow-up their health status, and detect early symptoms of COVID-19. MONITOR provides daily notifications for any suspected cases and activates a COVID-19 testing request and follow-up of results. This intervention helps rapidly identify and isolate suspected cases, as well as follow-up of work and family contacts, to prevent further outbreaks. Use of MONITOR has thus enabled containment of COVID-19 in workplaces and safe return to work. MONITOR is an example of the implementation of public health practices in workplaces and can serve as the basis for larger deployment in population-wide settings.

Background The emergence of assisted reproductive technology (ART) in humans has been an important tool for the treatment of infertility. The number of treatments performed in Latin America has been increasing, and Mexico is the third country with the most assisted reproduction cycles performed in the region. However, Mexico lacks a national regulation for assisted reproduction. Therefore, it is necessary to implement regulations that allow for a safe clinical practice based on ethics which can be available to any social group. Main body The aim of this review was to examine the existing legislation that regulates human assisted reproduction practices in Mexico, but also to examine the legal analysis of the policies, laws, and regulations in effect in some countries in Latin America, North America, and Europe. For this, seven databases were consulted, and 34 articles from 2004 to 2021 referring to the practice of ART within the legal framework and the anthropological analysis that this entails were analyzed. Eight documents were also consulted such as the Mexican General Health Law of the Official Journal of the Federation (February 7, 1984) with its last published reform (DOF 01-06-2021). And three official agency websites were also consulted. No specific legislation was found for human assisted reproduction practices in Mexico; however, assisted reproduction clinics are ruled under some agreements implemented by national organizations such as the Mexican Association of Reproductive Medicine and, at the Latin America level, the Latin America Network of Assisted Reproduction (abbreviated REDLARA in Spanish); in addition, the practice of ART is considered, although not explicitly, in the General Health Law. Conclusion In Mexico, there is no legal regulation in charge of assisted reproduction practices, which is why there is an urgent need to establish human assisted reproduction laws without incurring discriminatory and unconstitutional acts, and at the same time, be in accordance with scientific advances. This will allow a considerable reduction in the violation of human rights., Plain language summary The emergence of ART in humans has been an important tool for the treatment of infertility. It is reported that one in four couples in developing countries has fertility problems. In 2009, the International Committee for Monitoring Assisted Reproductive Technology (ICMART) established ART as "all treatments or procedures involving in vitro manipulation of oocytes, sperm or embryos for the purpose of establishing a pregnancy". The number of treatments performed in Latin America has been increasing, and Mexico is the third country with the most assisted reproduction cycles performed in the region. However, Mexico lacks a national regulation for human assisted reproduction. This has caused Mexico to become a medical tourism paradise, which increases the possibility of abuses, fraud, and clinical risks. In addition, it allows each institution offering assisted reproduction services, whether public or private, to establish arbitrary requirements for inclusion. Thus, the emergence of a regulation that allows a safe clinical practice based on ethics, which will also make this reproductive tool available to any social group, is a social need. Therefore, the aim of this review was to examine the existing legislation that regulates human assisted reproduction practices in Mexico, but also to examine the legal analysis of the policies, laws, and regulations in use in some countries in Latin America, North America, and Europe, as well as highlighting the importance of working on the establishment of regulations that allow for safe and ethically based clinical practices.

Background The evaluation of the DNA damage generated in cumulus cells after mature cumulus-oocyte complexes vitrification can be considered as an indicator of oocyte quality since these cells play important roles in oocyte developmental competence. Therefore, the aim of this study was to determine if matured cumulus-oocyte complexes exposure to cryoprotectants (CPAs) or vitrification affects oocytes and cumulus cells viability, but also if DNA damage is generated in cumulus cells, affecting fertilization and embryo development. Results The DNA damage in cumulus cells was measured using the alkaline comet assay and expressed as Comet Tail Length (CTL) and Olive Tail Moment (OTM). Results demonstrate that oocyte exposure to CPAs or vitrification reduced oocyte (75.5 ± 3.69%, Toxicity; 66.7 ± 4.57%, Vitrification) and cumulus cells viability (32.7 ± 5.85%, Toxicity; 7.7 ± 2.21%, Vitrification) compared to control (95.5 ± 4.04%, oocytes; 89 ± 4.24%, cumulus cells). Also, significantly higher DNA damage expressed as OTM was generated in the cumulus cells after exposure to CPAs and vitrification (39 ± 17.41, 33.6 ± 16.69, respectively) compared to control (7.4 ± 4.22). In addition, fertilization and embryo development rates also decreased after exposure to CPAs (35.3 ± 16.65%, 22.6 ± 3.05%, respectively) and vitrification (32.3 ± 9.29%, 20 ± 1%, respectively). It was also found that fertilization and embryo development rates in granulose-intact oocytes were significantly higher compared to denuded oocytes in the control groups. However, a decline in embryo development to the blastocyst stage was observed after CPAs exposure (1.66 ± 0.57%) or vitrification (2 ± 1%) compared to control (22.3 ± 2.51%). This could be attributed to the reduction in both cell types viability, and the generation of DNA damage in the cumulus cells. Conclusion This study demonstrates that oocyte exposure to CPAs or vitrification reduced viability in oocytes and cumulus cells, and generated DNA damage in the cumulus cells, affecting fertilization and embryo development rates. These findings will allow to understand some of the mechanisms of oocyte damage after vitrification that compromise their developmental capacity, as well as the search for new vitrification strategies to increase fertilization and embryo development rates by preserving the integrity of the cumulus cells.

Quadrivalent influenza vaccines (QIVs) are designed to prevent influenza disease caused by two influenza A viruses (H1N1 and H3N2) and both influenza B lineages. Risk-monitoring of QIVs to identify adverse events (AEs) is necessary as influenza vaccines are reformulated each year. We developed a new active surveillance system (

Simple Summary Recently, a significant relationship between stress and reproductive failure in women was reported; being one of the possible causes of infertility. The World Health Organization recognizes infertility as a global public health issue; therefore, the interest in understanding the main causes of this issue has increased over the last few decades. Thus, many studies have reported that stress can adversely alter the functionality of the hypothalamic-pituitary-gonadal axis; as well as being one of the reasons of subfertility in patients undergoing in vitro fertilization. Therefore, it can be assumed that stress is closely related to poor in vitro fertilization outcomes. In chronically stressed female rats, irregular estrous cyclicity, increased corticosterone levels, decreased oocyte viability, and increased percentage of abnormal oocytes were obtained in all estrous cycle phases, resulting in reduced oocyte maturation during proestrus. Oocyte maturation disturbed by chronic stress is a crucial factor by which chronic stress disrupts female reproduction. Abstract Background: Stress has been considered as one of the causes of decreased reproductive function in women. However, direct evidence of the effect of chronic stress on oocytes depending on estrous cycle phases is limited. Objective: The present study aimed to evaluate the impact of chronic stress on the viability, integrity, and maturation of rat oocytes depending on estrous cycle phases, specifically proestrus, estrus, and diestrus. Methods: For this purpose, adult female rats were stressed daily by cold water immersion (15 °C) for 30 consecutive days. Results: In chronically stressed female rats, irregular estrous cyclicity, increased corticosterone levels, decreased oocyte viability, and an increased percentage of abnormal oocytes were obtained in all the estrous cycle phases, resulting in reduced oocyte maturation during proestrus. Conclusion: Oocyte maturation disturbed by chronic stress is a crucial factor by which chronic stress disrupts female reproduction

Perfluorodecanoic acid (PFDA) is a synthetic perfluorinated compound, which has been reported to exert adverse effects on somatic cells. However, its effects on germ cells have not been studied to date. The aim of the present study was to analyze the effects of PFDA on the viability, intracellular calcium levels and gap junction intercellular communication (GJIC) during porcine oocyte maturation in vitro. PFDA negatively impacted oocyte viability (medium lethal concentration, LC50 = 7.8 μM) and maturation (medium inhibition of maturation, IM50 = 3.8 μM). Oocytes exposed to 3.8 μM PFDA showed higher levels of intracellular calcium relative to control oocytes. In addition, GJIC among the cumulus cells and the oocyte was disrupted. The effects of PFDA on oocyte calcium homeostasis and intercellular communication seem to be responsible for the inhibition of oocyte maturation and oocyte death. In addition, since the deleterious effects of PFDA on oocyte viability, maturation and GJIC are significantly stronger than the previously reported effects of another widely used perfluorinated compound (Perfluorooctane sulfonate) in the same model, the use of PFDA in consumer products is questioned.

Vitrification is mainly used to cryopreserve female gametes. This technique allows maintaining cell viability, functionality, and developmental potential at low temperatures into liquid nitrogen at −196°C. For this, the addition of cryoprotectant agents, which are substances that provide cell protection during cooling and warming, is required. However, they have been reported to be toxic, reducing oocyte viability, maturation, fertilization, and embryo development, possibly by altering cell cytoskeleton structure and chromatin. Previous studies have evaluated the effects of vitrification in the germinal vesicle, metaphase II oocytes, zygotes, and blastocysts, but the knowledge of its impact on their further embryo development is limited. Other studies have evaluated the role of actin microfilaments and chromatin, based on the fertilization and embryo development rates obtained, but not the direct evaluation of these structures in embryos produced from vitrified immature oocytes. Therefore, this study was designed to evaluate how the vitrification of porcine immature oocytes affects early embryo development by the evaluation of actin microfilament distribution and chromatin integrity. Results demonstrate that the damage generated by the vitrification of immature oocytes affects viability, maturation, and the distribution of actin microfilaments and chromatin integrity, observed in early embryos. Therefore, it is suggested that vitrification could affect oocyte repair mechanisms in those structures, being one of the mechanisms that explain the low embryo development rates after vitrification.

Limited information is available to determine the effectiveness of Mexico’s national influenza vaccination guidelines and inform policy updates. We aim to propose reforms to current influenza vaccination policies based on our analysis of cost-effectiveness studies. This cross-sectional epidemiological study used influenza case, death, discharge and hospitalization data from several influenza seasons and applied a one-year decision-analytic model to assess cost-effectiveness. The primary health outcome was influenza cases avoided, secondary health outcomes were influenza-related events associated with case reduction. By increasing vaccination coverage to 75% in the population aged 12–49 years with risk factors (diabetes, high blood pressure, morbid obesity, chronic renal failure, asthma, pregnancy), and expanding universal vaccination coverage to school-aged children (5–11 years) and adults aged 50–59 years, 7142–671,461 influenza cases, 1–15 deaths, 7615–262,812 healthcare visits, 2886–154,143 emergency room admissions and 2891–97,637 hospitalizations could be prevented (ranges correspond to separate age and risk factor groups), with a net annual savings of 3.90 to 111.99 million USD. Such changes to the current vaccination policy could potentially result in significant economic and health benefits. These data could be used to inform the revision of a vaccination policy in Mexico with substantial social value.

The Mexican influenza vaccination program does not include a recommendation for people aged 50–59 years without risk factors for influenza complications, and there are limited data regarding the cost-effectiveness of vaccinating this population. To explore the clinical and economic effects of including this population in the vaccination schedule, we performed a cross-sectional epidemiological study using records (2009–2018) from Mexico’s Influenza Surveillance System (SISVEFLU), death records (2010–2015) from the National Mortality Epidemiological and Statistical System, and discharge and hospitalization records (2010–2015) from the Automated Hospital Discharge System databases. A 1-year decision-analytic model was used to assess cost-effectiveness through a decision-tree based on data from SISVEFLU. The primary outcome was influenza cases avoided, with associated influenza-related events as secondary outcomes. Including the population aged 50–59 years without risk factors in Mexico’s influenza immunization program would have resulted in 199,500 fewer cases, 67,008 fewer outpatient consultations, 33,024 fewer emergency room consultations, 33,091 fewer hospitalizations, 12 fewer deaths. These reductions equate to a substantial public health benefit as well as an economic benefit, yielding net savings of 49.8 million US dollars over a typical influenza season. Expansion of the current Mexican vaccination schedule to include these people would be a cost-saving and dominant strategy.

We aimed to estimate vaccination coverage and factors associated in completing schemes in children under 5 years old between 2000 and 2018. A secondary analysis was carried out on five national health surveys between 2000 and 2018 in Mexico. The sample was 53,898 children under 5 years old, where 30% of missing vaccination information was imputed using chained equations. During this period two basic vaccination schemes (CBS) were identified. For each doses and vaccines of both schemes and completed CBS, the coverage was estimated using weighted logistic regression models. Additionally, the factors associated with incomplete schemes were reported. Between 2000 and 2018, the caretakers who did not show the vaccination card went from 13.8% to 45.6%. During this period, the estimated vaccination coverages did not exceed 95%, except for BCG and marginally the first doses of vaccines against pneumococcus, acellular pentavalent, and Sabin. In the same period, the CBS estimated coverage decreased steadily and was under 90%, except for children aged 6–11 months (92.6%; 91.5–93.7) in 2000. Not having health insurance stands out as an associated factor with incomplete vaccination schemes. In conclusion, the imputation allowed to recuperate information and obtain better data of vaccination coverage. The estimated vaccination coverage and CBS do not reach sufficient levels to guarantee herd immunity, hence innovative strategies to improve vaccination must be established in Mexico.

Introduction: the identification of vulnerable population groups through active surveys is aimed at preventing contagion through different measures or interventions. Objective: to characterize vulnerable older adults to Covid-19 with a personal pathological history of cardiovascular diseases. Method: an observational, descriptive and cross-sectional study was conducted at No-3 Family Doctor’s Office belonging to Manuel Piti Fajardo Rivero University Polyclinic in Las Tunas province, including the period defined between March and July 2020. The target group included 90 old people from 65 years or older having a personal pathological history of cardiovascular disease, working with all of them. Results: it was found a predominance of female sex (70 %) and the age group from 65 to 70 (35,6 %). According to personal medical history, 100 % of older adults were hypertensive, and 70 % suffered from cardiovascular diseases other than hypertension; 85,7 % of the patients maintained a standard therapeutic adherence to the treatments for the underlying diseases; 60 % of the patients were compensated during the period studied. Conclusions: the vulnerable older adults having a history of cardiovascular diseases were mainly female. Hypertension was shown as the main cardiovascular antecedent. Standard therapeutic adherence and stable underlying diseases were common in these patients.

Vitrification may severely affect cumulus cells and oocyte morphology and viability, limiting their maturation and developmental potential. The aim of this study was to evaluate the gap junction intercellular communication (GJIC) integrity after the vitrification of porcine immature cumulus-oocyte complexes (COCs). Fresh COCs were randomly distributed in three groups: untreated (control), toxicity (cryoprotectants exposure), and vitrification, then subjected to in vitro maturation (IVM). Oocyte viability and IVM were measured in all groups. The evaluation of GJIC was expressed as relative fluorescence intensity (RFI). Vitrification significantly decreased oocyte viability and maturation after 44 h of culture compared to control. Also, significantly reduced RFI was observed in vitrified COCs during the first hours of culture (4–8 h) compared to control. This study demonstrates that porcine oocyte viability and maturation after 44 h of culture decreased after vitrification. GJIC was also affected during the first hours of culture after the vitrification of immature oocytes, being one of the possible mechanisms by which oocyte maturation decreased.

Introduction: cardiovascular diseases are the first cause of death in Cuba; as a result, the identification of cardiovascular risks from early ages allows the implementation of health promotion and prevention strategies to reduce their impact in the future Objective: to identify the cardiovascular risk in medical students in Puerto Padre Municipality, Las Tunas province. Methods: an observational, descriptive and cross-sectional study was conducted. The target group included 545 medical students, 237 of whom were selected by means of a simple random sample. The body mass index and waist-hip ratio were studied. Descriptive statistics was applied. Results: the predominant age group was 18-21 years old (50,2 %). The 51,47 % of the students presented a high waist-hip ratio, 54,02 % a high abdominal circumference, 52,74 % a high body mass index, and in all groups 35,44 % presented blood pressure figures lower than 120/80 mmHg; 39 % had a cardiovascular risk. Conclusions: low percentages of cardiovascular risk were identified in medical students from Puerto Padre Municipality, Las Tunas province, determined by high values of waist-hip index, body mass index and abdominal circumference.

Background: senior citizens are those more vulnerable and with greater risk to progress to serious forms of COVID-19.Objective: to identify risks and vulnerabilities to COVID-19 in senior citizens older than 65 years of age belonging to the “Manuel Piti Fajardo Rivero” University Polyclinic of the municipality of Las Tunas, from April to June 2020.Methods: an observational, descriptive and cross-sectional study was carried out with a sample of 130 senior citizens belonging to the aforementioned health district and during the period herein declared. The following variables were assessed: age, sex, living with other people, past medical history, nutritional condition, visiting the emergency department, acquiescence in protection measures, assessment of the student active screening, among others.Results: there were more women (85 for 65,38 %) and adults between 65 and 70 years (53, 40,77 %). There was a predominance of those living with one or more persons (71,53 %), with a past medical history of cardiovascular conditions (69,23 %), normoweight (56,15 %), and movement restriction (40,79 %), non-visiting the emergency department (87,07 %). All of them wore the mask, observed the regular treatment for basic diseases (64,61 %), and, with symptoms as fever, reported to visit the doctor (90,76 %). The criterion on an adequate student active screening prevailed (97,69 %).Conclusions: advanced age and comorbidity with cardiovascular conditions were the risks identified for COVID-19.

Parabens (PBs) are compounds widely used in industry for food and personal care products as antimicrobials and preservatives. Their indiscriminate use has resulted in their detection in different ecosystems so that humans and other organisms are highly exposed. Methylparaben (MePB), compared with other PBs, is mostly detected in food, personal care and baby care products. PBs could be linked to the generation of hormonal disorders and fertility impairment since their recent classification as endocrine disruptors. The knowledge of the effects that MePB can exert is of great importance as, in terms of reproduction, information is limited. Therefore, the objective of the present study was to evaluate the effect of MePB on porcine oocyte viability and in vitro maturation (IVM), as well as to determine the lethal concentration at 50% (LC50 ) and the maturation inhibition concentration at 50% (MIC50 ). Oocytes were exposed to different MePB concentrations 0 (control), 50, 100, 500, 750 and 1000 μm during 44 h of IVM. Cytoplasmic alterations and reduced cumulus cell expansion were observed in oocytes exposed to MePB; however, viability was not affected. In addition, oocyte maturation decreased in a concentration-dependent manner after exposure to MePB. The estimated LC50 was 2028.38 μm, whereas MIC50 was 780.31 μm. To our knowledge, this is the first study that demonstrates that MePB altered porcine oocyte morphology, and caused a reduction in cumulus cell expansion, both of which resulted in decreased oocyte maturation. Therefore, MePB exposure may be one of the factors involved in fertility impairment in mammals, including that of humans.

Perfluorooctanoic acid (PFOA) is a member of the perfluoroalkyl acid family of compounds. Due to the presence of strong carbon-fluorine bonds, it is practically nonbiodegradable and highly persistent in the environment. PFOA has been detected in the follicular fluid of women, and positively associated with reduced fecundability and infertility. However, there are no reports concerning the experimental evaluation of PFOA on oocyte toxicity in mammals. The aim of the present study was to determine if PFOA is able to induce oxidative stress in fetal ovaries and cause apoptosis in oocytes in vitro. In addition, since inhibition of the gap junction intercellular communication (GJIC) by PFOA has been demonstrated in liver cells in vivo and in vitro, the effect of PFOA on the GJIC between the oocyte and its supportive cumulus cells was studied. Results show that PFOA induced oocyte apoptosis and necrosis in vitro (medium lethal concentration, LC50 = 112.8 μM), as evaluated with Annexin-V-Alexa 508 in combination with BOBO-1 staining. Reactive oxygen species (ROS) levels, as assessed by DCFH-DA, increased significantly in fetal ovaries exposed to ¼ LC50 (28.2 μM, a noncytotoxic and relevant occupational exposure concentration) and LC50 PFOA ex vivo. This perfluorinated compound also caused the blockage of GJIC in cumulus cells-oocyte complexes (COCs) obtained from female mice exposed in vivo, as evaluated by calcein transfer from cumulus cells to the oocyte. The ability of PFOA of disrupting the GJIC in COCs, generating ROS in the fetal ovary and causing apoptosis and necrosis in mammal's oocytes, might account for the reported association between increasing maternal plasma concentrations of PFOA with reduced fertility in women.

Glyphosate [N-(phosphonomethyl)glycine] is the active ingredient in widely used broad-spectrum herbicides. Even though the toxicity mechanism of this herbicide in vertebrates is poorly understood, evidence suggests that glyphosate is an endocrine disruptor capable of producing morphological anomalies as well as cardiotoxic and neurotoxic effects. We used the zebrafish model to assess the effects of early life glyphosate exposure on the development of cartilage and bone tissues and organismal responses. We found functional alterations, including a reduction in the cardiac rate, significant changes in the spontaneous tail movement pattern, and defects in craniofacial development. These effects were concomitant with alterations in the level of the estrogen receptor alpha osteopontin and bone sialoprotein. We also found that embryos exposed to glyphosate presented spine deformities as adults. These developmental alterations are likely induced by changes in protein levels related to bone and cartilage formation.

IntroductionTo present an analysis of the Brazilian health system and subnational (state) variation in response to the COVID-19 pandemic, based on 10 non-pharmaceutical interventions (NPIs).Materials and methodsWe collected daily information on implementation of 10 NPI designed to inform the public of health risks and promote distancing and mask use at the national level for eight countries across the Americas. We then analyse the adoption of the 10 policies across Brazil’s 27 states over time, individually and using a composite index. We draw on this index to assess the timeliness and rigour of NPI implementation across the country, from the date of the first case, 26 February 2020. We also compile Google data on population mobility by state to describe changes in mobility throughout the COVID-19 pandemic.ResultsBrazil’s national NPI response was the least stringent among countries analysed. In the absence of a unified federal response to the pandemic, Brazilian state policy implementation was neither homogenous nor synchronised. The median NPI was no stay-at-home order, a recommendation to wear masks in public space but not a requirement, a full school closure and partial restrictions on businesses, public transportation, intrastate travel, interstate travel and international travel. These restrictions were implemented 45 days after the first case in each state, on average. Rondônia implemented the earliest and most rigorous policies, with school closures, business closures, information campaigns and restrictions on movement 24 days after the first case; Mato Grosso do Sul had the fewest, least stringent restrictions on movement, business operations and no mask recommendation.ConclusionsThe study identifies wide variation in national-level NPI responses to the COVID-19 pandemic. Our focus on Brazil identifies subsequent variability in how and when states implemented NPI to contain COVID-19. States’ NPIs and their scores on the composite policy index both align with the governors’ political affiliations: opposition governors implemented earlier, more stringent sanitary measures than those supporting the Bolsonaro administration. A strong, unified national response to a pandemic is essential for keeping the population safe and disease-free, both at the outset of an outbreak and as communities begin to reopen. This national response should be aligned with state and municipal implementation of NPI, which we show is not the case in Brazil.

The in vitro and in vivo antihelmintic activity of cobalt(II), copper(II) and zinc(II) coordination compounds of tinidazole (tnz) were investigated in cultivated spotted rose snapper, infested with dactylogyrid monogeneans. The tinidazole coordination compounds [Co(tnz)2Cl2], [Co(tnz)2Br2], [Cu(tnz)2Cl2], [Cu(tnz)2Br2], [Zn(tnz)2Cl2] and [Zn(tnz)2Br2] were synthesized and spectroscopically characterized. Their molecular structures were determined by their single crystal X-ray diffraction. The metal ions presented distorted tetrahedral geometries, with an intramolecular bifurcated lone pair S O ⋯ π, from the sulfone group with the imidazolic ring, which contributed to the stability of the compounds in solid state and in solution. Adults of dactylogyrids were exposed in vitro to tinidazole and its coordination compounds. The effective median concentrations of copper(II) coordination compounds were lower than those of cobalt(II) and zinc(II), tnz showed no activity. In vivo oral intubation tests were carried out with [Cu(tnz)2Br2], [Zn(tnz)2Br2] and tnz on snappers infected with dactylogyrids, where the copper(II) compound showed better activity. The absorption and distribution assessment for the [Cu(tnz)2Br2], showed that copper concentrations in liver were significantly higher than in blood and gills, indicating bioaccumulation in this organ. In vivo baths of [Cu(tnz)2Br2] at 25 mg/L showed an effective (95% at 8 h) antihelmintic effect, while [Zn(tnz)2Br2] had low antihelmintic efficacy. This study indicates that [Cu(tnz)2Br2] has an effective antihelmintic activity towards dactylogyrids monogeneans affecting cultivated spotted red snapper.

Perfluorohexane sulfonate (PFHxS) is one of the most abundant perfluorinated compounds in the environment. Exposure to this compound has been correlated to a decrease in human fertility, although the molecular and cellular mechanisms underlying this correlation have not been described. The adverse reproductive effects of PFHxS could be based on alterations in oocyte maturation, the process rendering oocytes competent for fertilization. The aim of this study was to evaluate the effect of PFHxS on porcine oocyte viability and maturation in vitro, as well as on gap-junctional intercellular communication (GJIC) in cumulus–oocyte complexes (COCs), oocyte mitochondrial membrane potential (mΔΨ) and DNA damage in cumulus cells, as possible mechanisms of action. PFHxS caused cytotoxicity (medium lethal concentration, LC50 = 329.1 μM) and inhibition of oocyte maturation (medium inhibitory concentration, MIC50 = 91.68 μM). GJIC was not affected in exposed COCs. However, the mitochondrial membrane potential was significantly decreased in PFHxS-exposed oocytes at the germinal vesicle breakdown (GVBD) stage. In addition, exposure to PFHxS induced DNA damage in cumulus cells. Thus, inhibition of oocyte maturation by PFHxS could be attributed to a decreased oocyte mΔΨ at the GVBD and to DNA damage of the cumulus cells that support the oocyte.

Background In order to improve ICSI, appropiate sperm selection and oocyte activation is necessary. The objective of the present study was to determine the efficiency of fertilization using ICSI with chemically activated ovine oocytes and sperm selected by swim up (SU) or swim up + zona pellucida (SU + ZP) binding. Results Experiment 1, 4–20 replicates with total 821 in vitro matured oocytes were chemically activated with ethanol, calcium ionophore or ionomycin, to determine oocyte activation (precense of one PN). Treatments showed similar results (54, 47, 42 %, respectively) but statistically differents (P 0.05). Conclusions Chemical activation induces higher ovine oocyte activation than mechanical activation. Ethanol slightly displays higher oocyte activation than calcium ionophore and ionomicine. Sperm selection with SU + ZP increased AR/A and AR/D rates in comparison with SU in fresh and frozen-thawed sperm. According to this, in terms of fertilization rates, chemical activation after ICSI increased oocyte PN formation compared to mechanical activation. Also, fresh sperm treated with SU and SU + ZP were significantly different than frozen-thawed sperm, but between sperm treatments no significant differences were obtained.

Perfluorooctane sulfonate (PFOS) is a broadly used man-made surfactant whose long half-life has led to bioaccumulation. This perfluorinated compound is ubiquitous in human body fluids. PFOS concentrations as high as 26μM in plasma have been reported in occupationally exposed populations, and high levels of PFOS in human follicular fluid have been associated with subfertility. However, the effect of PFOS on the maturation of oocytes in mammals has not been reported to date. The aim of this study was to determine the effects of PFOS during oocyte maturation. Results indicate that PFOS inhibits oocyte viability (Lethal Concentration50=32μM) and maturation (inhibition of maturation50=22μM) at physiologically relevant concentrations. In order to evaluate the mechanisms of oocyte maturation inhibition by PFOS, gap junctional intercellular communication (GJIC) between oocytes and granulosa cells was assessed. GJIC between granulosa cells and the oocyte was significantly affected during the first 8h of maturation. However, the inhibitory effect of PFOS on GJIC was not due to an alteration on the expression of connexin genes Cx43, Cx45 and Cx60. These findings suggest that occupationally exposed populations could be at risk, and that PFOS might affect oocyte maturation by interfering the GJIC in the cumulus-oocyte complexes during the first hours of maturation.

There is little information in the scientific literature concerning sheep pregnancy and lambing success with regard to the timeframe from when in vitro produced embryos are transported to the designated location for embryo transfer (ET). The aim of this study was to transfer in vitro produced embryos under two different conditions that could typically occur using the aforementioned assisted reproductive techniques (ARTs). Abattoir ovaries were used to procure oocytes for in vitro embryo production and subsequent transfer to synchronized ewes. The study consisted of two experiments: Experiment 1 (Exp1)—embryos taken from the laboratory to a nearby surgical room for immediate ET, and Experiment 2 (Exp2)—ET after 5 hours (h) of transport to a rural farm. Lambing in relation to detected pregnancies, births compared to pregnancies, and the proportion of twin offspring were all higher in Exp2. Notably, in both Exp1 and Exp2, there was not a significant difference (P > 0.05) between the number of embryos transferred, i.e., 3 versus 4, respectively, and the number of ewes that underwent parturition in each group. Also, in both experiments there was not a significant difference (P > 0.05) in the number of ewes that underwent parturition based on the number (i.e., ≥1) of corpora lutea present. The results of the present study demonstrate the importance of evaluating different conditions when applying ARTs, as there are many variables that can influence the outcome. Importantly, Exp2 results show that ovine ET in places located far away from the embryo production site can be useful and successful provided that embryo transport, ET, and recipient conditions are adequate.

Background Most studies carried out to evaluate recovery and development after porcine oocyte vitrification, reported better rates when cryopreserved in embryonic development stages or zygotes, but not in immature oocytes. For this reason, many studies are performed to improve immature oocyte vitrification protocols testing the use of different cryoprotectant concentrations, cooling devices, incubation times; but only a few of them have evaluated which fertilization procedure enhances blastocyst rates in vitrified oocytes. Therefore, this study was aimed to evaluate: 1) if the sperm selection with hyaluronic acid (HA) or polyvinylpyrrolidone (PVP) before injection could play a key role in increasing fertilization and blastocyst formation and 2) the embryo developmental ability and blastocyst production of porcine immature oocytes retrieved after vitrification-warming and co-cultured with granulosa cells during IVM, using different fertilization techniques: in vitro fertilization (IVF), intracytoplasmic sperm injection (ICSI) and conventional ICSI with hyaluronic acid (HA) sperm selection, known as physiological intracytoplasmic sperm injection (PICSI) and. Results Sperm selected with HA-PICSI displayed a higher percentage of live/acrosome reacted status compared to those in control and exposed to PVP. Higher dead/acrosome reacted rates were obtained after PVP exposure compared to control and HA. In oocytes, viability significantly decreased after IVM in vitrified oocytes. Besides, IVM rates were not different between control denuded oocytes cultured with granulosa cells (DO-GC) and vitrified oocytes. Regarding fertilization parameters, IVF showed higher percentages of total fertilization rate than those obtained by ICSI and PICSI. However, results demonstrate that PICSI fertilization increased the blastocysts formation rate in control DO-GC and vitrified oocytes compared to IVF and ICSI. Conclusions To achieve high blastocyst formation rates from vitrified GV oocytes, it is recommended that sperm should be selected with HA instead of PVP before injection since high viability and acrosome reaction rates were obtained. Also, PICSI fertilization was the best method to produce higher blastocyst rates compared to the IVF and ICSI procedures.

Fish consumption is the major source of mercury to humans. Fetuses and children are the most sensitive groups of populations to the effects of mercury. Consequently, fish consumption by pregnant women, children, and women of childbearing age is of concern because of the effects of mercury exposure on human health. To assess mercury exposure in a population in northwest Mexico, the allowed daily consumption of fish (which indicates the maximum daily amount of fish that can be consumed without causing adverse noncarcinogenic effects) was calculated for the general population (GP) and fishing-related population (FRP). The studied groups for both sectors of the population were children A (3-10 years old), children B (11-15 years old), women of childbearing age (16-40 years old), and the rest of the population (men ≥16 years old, and women ≥41 years old). Mercury content in canned and frozen tuna, smoked marlin, tilapia, Pacific sierra, dolphinfish, and bullseye puffer ranged from 0.01 to 0.23 μg/g wet weight; none of the values were above the limit set by Mexico. Regarding mercury concentrations and rates of fish consumption, the GP consumes 1.7-2.7 times the allowed daily consumption, and the FRP consumes 1.6-3.9 that limit. The risk analysis showed the children A and B groups from the GP and adults of FRP to be the highest percentage of the population at risk (approximately 35%). These results highlight the need for adequate strategies that consider mercury exposure as part of public health policies associated with fish consumption in Mexico.

Previous studies with perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) indicate that they act as endocrine disruptors, in addition to inducing alterations and damaging reproductive health; however, the biological mechanisms by which these disorders are produced are not yet understood. The aim of this study was to analyze the effect of PFOS and PFOA on in vitro steroidogenic secretion in porcine theca and granulosa cells, with or without gonadotropic stimulation. Granulosa and theca cells were isolated and cultured. Cell nature was performed by immunocytochemistry. PFOS and PFOA effect on steroid secretion was analyzed by chemiluminescence. In the present study, alterations in steroidogenic secretion were found when administering PFOS (0.12, 1.2, 12, 120 or 240 μM) or PFOA (0.012, 0.12, 1.2, 12 or 24 μM) to theca and granulosa cells. When theca and granulosa cells were stimulated with 500 ng/mL LH or 500 ng/mL FHS, respectively and immediately followed with 1.2 μM of PFOS or PFOA, the perfluorinated compounds inhibited the secretion of steroid hormones in both stimulated cell types. The results indicate that PFOS and PFOA act on steroidogenic ovarian cells as endocrine disruptors, which could affect the dependent functions of sexual steroids.

Summary Noncommunicable diseases (NCDs) are the leading causes of death globally, killing more people each year than all other causes combined. The principal factors that influence the emergence of NCDs are the combination of changes in urbanization, global trade markets, and longevity that has been occurring over decades in wealthy nations but are happening much faster in emerging countries. These changes come through the inability of developing countries to reestablish health and regulatory systems rapidly enough to keep pace with the changes. The consequences are devastating everywhere, but especially in vulnerable and disadvantaged populations. These people get sick sooner and die earlier than in wealthier societies. Usually, noncommunicable diseases are detected late, when patients need extensive and expensive hospital care for severe complications or acute events. Effective interventions are available, and evidence demonstrates their clear and measurable impact on a range of resource settings. Some of these interventions are continuing medical education as a response to the need to maintain postgraduate qualification and guarantee the quality of health care and promote the creation of care innovations that transform the primary health care system. The Carlos Slim Foundation established the CASALUD model to develop innovative public health strategies that transform primary care by improving the delivery of chronic disease management through the implementation of care innovations. This model includes electronic health education with PIEENSO ( http://pieenso.org/ ), an educational health platform established to contribute to the generation of sustained health initiatives that aim to have a profound impact on the people in Mexico and Latin America. PIEENSO provides health professionals academic tools to achieve meaningful learning and strengthening of skills in relevant public health issues. This model is among the first that includes education for physicians and other primary health care professionals, and focuses on CKD detection and prevention as a part of a comprehensive course on chronic noncommunicable diseases.

This study was designed to determine whether calreticulin (CRT), a chaperone protein, is present inin vitro-matured (IVM) pig oocytes and to study its potential role in the block to polyspermy. Western blot analysis, using an anti-CRT antibody, of oocyte lysate showed an immunoreactive band of ∼60 kDa. Simultaneous labeling of IVM oocytes with anti-CRT antibody and peanut agglutinin lectin (PNA lectin, a porcine cortical granules (CG)-specific binding lectin) revealed localization of CRT in the subplasmalemmal region with a 27.7% colocalization with PNA staining. After IVF, PNA labeling was not observed and anti-CRT labeling decreased significantly in zygotes and disappeared in two-cell embryos. Western blot analysis of oocyte exudate obtained from zona pellucida (ZP)-free oocytes activated with calcium ionophore confirmed the presence of a band that reacted with an anti-CRT antibody. Anti-CRT antibody and PNA labeling were not observed in activated oocytes despite being detectable in non-activated oocytes. The presence of CRT in vesicles located under the oolemma was demonstrated using immunogold cytochemistry at the ultrastructural level. To study the role of CRT in fertilization, ZP-enclosed and ZP-free oocytes were incubated with exogenous CRT and then inseminated. Whereas ZP-free oocytes showed fewer penetrating sperm and lower polyspermy rates than untreated oocytes, the opposite effect was observed in ZP-enclosed oocytes. In conclusion, CRT is confined to subplasmalemmal vesicles partially overlapping with CG contents. Its exocytosis after the oocyte activation seems to participate in the membrane block to polyspermy in pigs but is not involved in the ZP block.

The aim of this study was to determine the effect of Tai Chi on biological markers of oxidative stress in saliva and its relationship with periodontal disease (PD) in older adults. We carried out a quasi-experimental study with a sample of 71 sedentary volunteers with PD who were divided into a control group of 34 subjects and an experimental group of 37 subjects who performed Tai Chi 5 days a week for a period of 6 months. PD status was characterized using the Periodontal Disease Index (PDI). Superoxide dismutase (SOD), total antioxidant status (TAS), and TBARS levels of both groups were measured by spectrophotometric methods. In addition, inflammation markers (TNF-α, IL-1β, IL-6, IL-8, and IL-10) were measured by flow cytometry. We found a statistically significant increase in SOD activity (P<0.001) and TAS concentration (P<0.05), whereas levels of IL-1βwere significantly lower (P<0.01). Likewise, a statistically significant decrease in the PDI (P<0.05) was observed in subjects who performed Tai Chi during a period of 6 months. Our findings suggest that the practice of Tai Chi has both antioxidant and anti-inflammatory effects that are linked to the improvement of PD in older adults.

Several coastal lagoons and estuaries in Mexico receive untreated domestic and industrial discharges which contain complex mixtures of contaminants. In order to assess the effects of chemical contamination, we used the White mullet (Mugil curema) as biological indicator. We worked in two estuaries located in Northwest Mexico: Urias (highly polluted) and Teacapan (less polluted, therefore used as reference site). We measured several endpoints at different levels of biological organization: vitellogenin transcription in males as biomarker of estrogenic contamination, as well as reproductive, morphological (deformities), morphometric, and meristic parameters. Total RNA was isolated from the liver, and a partial sequence of the mullet vitellogenin gene was obtained; gene expression was analyzed by quantitative PCR. At the same time, gonad samples were analyzed by histologic techniques to determine sex ratios and the reproductive cycle stage. The reproductive season was detected from February to June in both sites, but the gonadosomatic index was consistently higher in Teacapan. Sex ratios were female-biased in both estuaries, and one intersex gonad and several malformations were found in fish from Urias. Vitellogenin gene transcription in males was detected in both sites, although gene expression was slightly higher in Urias. The results obtained in this study indicate that biological effects of contamination are evident in fish, environmental estrogens may be present in both estuaries, and the white mullet is useful as biological indicator to identify and characterize environmental stressors in tropical coastal ecosystems.

Malathion is one of the most commonly used insecticides. Recent findings have demonstrated that it induces oxidative stress in somatic cells, but there are not enough studies that have demonstrated this effect in germ cells. Malathion impairs porcine oocyte viability and maturation, but studies have not shown how oxidative stress damages maturation and which biochemical mechanisms are affected in this process in cumulus-oocyte complexes (COCs). The aims of the present study were to determine the amount of oxidative stress produced by malathion in porcine COCs matured in vitro, to define how biochemical mechanisms affect this process, and determine whether trolox can attenuate oxidative damage. Sublethal concentrations 0, 750, and 1000 µM were used to evaluate antioxidant enzyme expressions, reactive oxygen species (ROS production), protein oxidation, and lipid peroxidation, among other oxidation products. COCs viability and oocyte maturation decreased in a concentration-dependent manner. Malathion increased Cu, Zn superoxide dismutase (SOD1), glutathione-S-transferase (GST), and glucose 6 phosphate dehydrogenase (G6PD) protein level and decreased glutathione peroxidase (GSH-Px) and catalase (CAT) protein level. Species reactives of oxygen (ROS), protein oxidation and Thiobarbituric acid reactive substances (TBARS) levels increased in COCs exposed to the insecticide, but when COCs were pre-treated with the trolox (50 µM) 30 min before and during malathion exposure, these parameters decreased down to control levels. This study showed that malathion has a detrimental effect on COCs during in vitro maturation, inducing oxidative stress, while trolox attenuated malathion toxicity by decreasing oxidative damage.

Chagas disease is a leading cause of heart disease affecting approximately 10 million people in Latin America and elsewhere worldwide. The two major drugs available for the treatment of Chagas disease have limited efficacy in Trypanosoma cruzi-infected adults with indeterminate (patients who have seroconverted but do not yet show signs or symptoms) and determinate (patients who have both seroconverted and have clinical disease) status; they require prolonged treatment courses and are poorly tolerated and expensive. As an alternative to chemotherapy, an injectable therapeutic Chagas disease vaccine is under development to prevent or delay Chagasic cardiomyopathy in patients with indeterminate or determinate status. The bivalent vaccine will be comprised of two recombinant T. cruzi antigens, Tc24 and TSA-1, formulated on alum together with the Toll-like receptor 4 agonist, E6020. Proof-of-concept for the efficacy of these antigens was obtained in preclinical testing at the Autonomous University of Yucatan. Here the authors discuss the potential for a therapeutic Chagas vaccine as well as the progress made towards such a vaccine, and the authors articulate a roadmap for the development of the vaccine as planned by the nonprofit Sabin Vaccine Institute Product Development Partnership and Texas Children’s Hospital Center for Vaccine Development in collaboration with an international consortium of academic and industrial partners in Mexico, Germany, Japan, and the USA.

SummaryOogenesis is a highly complex process that requires the exquisite temporal and spatial regulation of gene expression at multiple levels. Skin–embryo–brain–oocyte homeobox (Sebox) gene encodes a transcription factor that is highly expressed in germinal vesicle stage oocytes and that plays an essential role in early embryogenesis at the 2-cell stage in the mouse. AsSeboxis also expressed in mouse fetal ovaries, the aim of the present study was to study its role during the early oogenesisin vitro. Expression ofSeboxwas low in 15.5 to 17.5 days post coitum (dpc) ovaries, showed a peak at 18.5 dpc and then its expression decreased dramatically in newborn ovaries.Seboxexpression was efficiently knocked down (>80%) in fetal mouse ovary explants in culture using RNAi technology. When fetal ovary explants were transfected withSebox-specific RNAi, the number of oocytes at germinal vesicle stage and showing a diameter of 40–70 μm was decreased significantly to 75% after 7 days of culture relative to the negative control, and to 22.4% after 10 days of culture, thus indicating thatSeboxplays an important role in the early oogenesis in mice.

Dengue infection is a significant and escalating public health problem in Latin America. Its re-emergence and subsequent rise in the region over the past 50 years has largely been caused by a combination of a lack of political will, the radical growth of urban populations, migration flow and insufficient financial resources. Its increased incidence has been compounded by climate change, poor sanitation and extreme poverty, which lead to more breeding sites of the mosquito vector Aedes aegypti. In order to control dengue effectively, an integrated approach incorporating vector management and environmental and social solutions is required. To achieve success, these programmes require commitment and responses at both national and community level. The development of a vaccine is a vital tool in the fight against dengue. For successful introduction, those implementing vaccination need to be educated on the value of such a strategy. Effective political leadership, innovative financial mechanisms and co-operation across all disciplines, sectors and national borders are essential to eradication of the disease.

We previously identified 62, 39, 27 and 7 kDa porcine sperm plasma membrane proteins that demonstrated a predominant affinity for the porcine oocyte plasma membrane by Western ligand blotting. The current experiments were designed to further investigate the potential roles of these molecules in sperm-oocyte plasma membrane interaction. Abilities of these proteins to bind to the oocyte plasma membrane and to inhibit sperm-oocyte interaction were evaluated. Plasma membrane was isolated primarily from the head of ejaculated porcine sperm by nitrogen cavitation and density gradient centrifugation. Fractions containing the 62, 39, 27 and 7 kDa proteins were electroeluted from one dimensional SDS polyacrylamide gels, dialysed and proteins biotinylated. Following incubation with zona-free porcine oocytes, bound protein was visualized with 20 μg TRITC-avidin/ml using confocal microscopy. Fractions of the dialysed, electroeluted proteins were added to porcine in vitro fertilization assays. The 62, 39, 27 and 7 kDa proteins all demonstrated binding to the oocyte plasma membrane in contrast to a biotinylated control protein. Addition of unlabelled sperm plasma membrane proteins to the biotinylated protein visibly reduced binding. Addition of each of these protein fractions to in vitro fertilization assays reduced sperm interaction with the porcine oocyte plasma membrane in a concentration-dependent manner. Binding of these sperm plasma membrane proteins to the oocyte plasma membrane and inhibition of fertilization are consistent with these proteins being involved in sperm-oocyte plasma membrane interaction.

Follicular apoptosis in the tropical mussel Mytella strigata was assessed in three coastal lagoons located in the southern Gulf of California, Mexico. Mussels were collected from three coastal lagoons associated with different scenarios of anthropogenic stress during one year. The gonad of each mussel was dissected, weighed, and sampled for histology and apoptosis analysis by TUNEL labeling. Two apoptotic indices were used: the apoptotic index of cells (AIC) based on the number of follicular cells in apoptosis in one thousand cells counted per gonad, and the apoptotic index of follicles (AIF) based on the number of follicular cells per follicle per gonad. Both indices showed high association with each other for all developmental stages, although AIF seemed to better discriminate among sites. Higher AIF and AIC were observed at the Urias Estuary (1.6 and 1.5 respectively) ranked as highly polluted, followed by Ensenada del Pabellon (0.82 and 0.95 respectively), ranked as moderately polluted, and the Teacapan Estuary (0.57 and 0.76 respectively) ranked as slightly polluted. Our data indicate that the apoptotic index in tropical mussels could be a useful indicator of environmental stress in coastal ecosystems; however, the ecological relevance of follicular apoptosis in polluted environments needs further investigation.

In an in vitro model using HEp-2 cells treated with purified plasmid-encoded toxin (Pet), we have identified morphological changes characterized by cell rounding and detachment after toxin internalization; these changes progress to cell death. However, these effects have not yet been shown to occur during the infection of epithelial cells by enteroaggregative Escherichia coli (EAEC). Here, we show that the secretion of Pet by EAEC is regulated at the transcriptional level, since secretion was inhibited in eukaryotic cell culture medium, although Pet was efficiently secreted in the same medium supplemented with tryptone. Inefficient secretion of Pet by EAEC in DMEM prevented cell detachment, whereas efficient Pet secretion in DMEM/tryptone increased cell detachment in a HEp-2 cell adherence assay. Interestingly, Pet toxin was efficiently delivered to epithelial cells, since it was internalized into epithelial cells infected with EAEC at similar concentrations to those obtained by using 37 μg ml−1 purified Pet protein. Additionally, Pet was not internalized when the epithelial cells were infected with a pet clone, HB101(pCEFN1), unlike the wild-type strain, which has a high adherence capability. There is a correlation between Pet secretion by EAEC, the internalization of Pet into epithelial cells, cell detachment and cell death in EAEC-infected cells. The ratio between live and dead cells decreased in cells treated with wild-type EAEC in comparison with cells treated with an isogenic mutant in the pet gene, whereas the effects were restored by complementing the mutant with the pet gene. All these data indicate that Pet is an important virulence factor in the pathogenesis of EAEC infection.

Malathion and diazinon are two of the most commonly used organophosphorous (OP) agrochemicals. Several studies show that these pesticides exert several effects on mammalian spermatogenesis. Nevertheless, there are no studies concerning their effects on oogenesis. The objective of this study was to evaluate the effects of these insecticides on the viability of in vitro cultured mouse oocytes during the early oogenesis and to get a further understanding of the molecular mechanisms by which OP insecticides act and affect germinal cells. Oocytes were cultured from fetal ovaries for 10 days, when most oocytes had reached the diplotene stage (germinal vesicle stage). Cultures were exposed to different concentrations of malathion or diazinon for 24 h, and the effect on oocyte viability was assessed. Gene expression in oocytes exposed to the insecticides was analyzed by generating cDNA libraries and performing differential screenings. Results show a significant decrease in oocytes survival after 24-h exposure to 250 μM malathion or 900 nM diazinon, and the effect of these insecticides on the regulation of genes encoding proteins involved in transcription (BP75), translation (ribosomal protein S5), and mitochondrial function (cytochrome oxidase subunits I and III), providing evidence for OP insecticides as toxicants for mammals oocytes during the early oogenesis. © 2008 Wiley Periodicals, Inc. Environ Toxicol, 2008.

Ancyrocephaline monogeneans such as Haliotrema sp. and Euryhaliotrema sp. are common parasites infecting gills on the red snapper, Lutjanus guttatus , an important potential fish species for aquaculture in Mexico. The effectiveness of different treatments against these monogeneans using in vitro and in vivo assessments on the viability of eggs and adults was evaluated. Eggs from both monogenean species were in vitro exposed to sodium hypochlorite, drying, formalin, and freshwater for 3 h, and returned to seawater to determine post-treatment hatching. Adults of both parasites were also in vitro exposed to formalin, freshwater, and caprylic acid for periods ranging from 10 to 60 min using seawater as control. In vivo tests were carried out with freshwater, formalin, and praziquantel (active ingredient of Drontal™ Plus and Vermiplex™ Plus) on snappers infected with both parasites. After 3 h exposure, egg hatching was completely suppressed at 120 mg l − 1 of available chlorine, while drying, formalin (83 mg l − 1 ) and freshwater showed eggs viabilities of 10, 23, and 10% respectively. In vitro freshwater exposure significantly reduced the mean intensity of ancyrocephaline adults (99% at 30 min), followed by formalin at 51 mg l − 1 (72% at 60 min) and caprylic acid at 334 mg l − 1 (5% at 30 min). In vivo freshwater baths for 30 min removed 100% of ancyrocephalines, although this method was stressful for the fish, while formalin (60 min at 51 mg l − 1 ), Drontal™ Plus (12-h at 4.5 mg l − 1 ) and Vermiplex™ Plus (24-h at 3.5–4.5 mg l − 1 ) removed 72, 100 and 100% respectively. This study indicates that praziquantel, freshwater, and formalin baths were effective against ancyrocephaline adults from red snapper, and sodium hypochlorite would be useful to prevent horizontal infection with eggs on fish-rearing facilities.

This study was designed to evaluate the capacity of vitrified-warmed porcine immature oocytes to mature and to be fertilized using in vitro fertilization or intracytoplasmic sperm injection, and to determine the subsequent embryo development. Immature oocytes were vitrified using ethylene glycol and dimethylsulphoxide as cryoprotectants and the Cryolock method. After warming oocytes were cultured 44 h for maturation. Oocytes were randomly distributed in three treatment groups and subjected to in vitro fertilization (Experiment 1) or intracytoplasmic sperm injection (Experiment 2) procedures. The results indicate that the embryo development was higher in denuded oocytes co-cultured with granulosa cells (NkO-CC group) fertilized by in vitro fertilization or intracytoplasmic sperm injection compared to cumulus-cell oocyte complexes (COCs group), showing no significant differences with control. Vitrified denuded oocytes matured with a co-culture system NkO-CC group, displayed higher cleavage rate and blastocyst production than vitrified COCs group. Blastocysts were successfully obtained after IVF and ICSI procedures; however, the development to the blastocyst stage was better after IVF. These results show that the vitrification-warming media, the employment of a granulosa cell co-culture system and the Cryolock method during vitrification, increased the nuclear and cytoplasmic maturation of vitrified porcine immature oocytes. Further experiments are required to enhance porcine embryo production after vitrification.