Twin births in Yucatan, Mexico during 2008-2020: trends in maternal sociodemographic factors and differences in birth weight and length according to sex of co-twin.

Background: Over the years, there has been a noticeable increase in the incidence of multiple pregnancies, due in part to the increased use of assisted reproductive technologies in recent years. The increase in twin pregnancies constitutes a public health challenge due to the adverse outcomes sometimes they entail. Twin pregnancies inherently carry a higher risk of complications, and one of the critical associated factors is the risk of low birth weight. Twin birth weight discordance among different populations can be attributed to differences in non-shared environmental influences. The presence of two or more fetuses in the uterus may lead to an unequal distribution of nutritional and oxygen resources, increasing the likelihood that at least one of the twins will experience insufficient fetal development. Other factors, such as ethnicity, genetics, sociodemographic characteristics, gestational age, parity, and chorion type, have also been related to the birth weight discordance in twin pregnancies. However, it is unclear to what extent the associations between these factors can explain the differences in birth and length size. The frequency of twin births varies among populations and over time, so it is crucial to gain a deeper understanding of the factors contributing to the rise in the twinning rate. The official records of twins continue to make significant contributions to our understanding of the causes of individual differences, and new twin registries are still being created. The recent availability of data from developing countries allows the analysis of trends in regions with sociodemographic and reproductive profiles. Obtaining a more comprehensive understanding of the epidemiology, as well as the related morbidity and mortality, is clinically crucial. Objectives: The aim of the study was to describe the trends of twin births in Yucatan, Mexico during 2008-2021, analyze their association with maternal sociodemographic factors, and compare birth outcomes between types of twin pairs: female-female, male-male, and female-male. Methods: A retrospective cohort analysis was conducted using data from the Mexican Ministry of Health, encompassing information on all births registered in the State of Yucatán, Mexico, from 2008 through 2021. The data was obtained from both public and private hospitals. The variables, including date of birth, sex, gestational age, birth weight and length of newborns, mother´s date of birth, educational level, and number of previous live offspring, were extracted from each dataset. Multiple births (three or more) were excluded from the study. We graphically analyzed the rates (per 1000 births) and percentages of twins according to maternal age, education level, and parity during the study period. A multiple logistic regression model was used to analyze the association between maternal sociodemographic factors and the occurrence of twin births. Comparisons of the gestational age and birth weight and length between types of twin pairs were performed using analysis of variance. Results: A total of 478,118 live births, including 1.4% twins (accounting 6,766 twin births), were analyzed. The rates increased from 11.21 during 2008-2011 to 13.34 during 2012-2017 and reached 20.08 in 2019. The percentages increased in women aged ≥30 years and those with higher educational levels. Older maternal age (coefficient = 0.03; OR = 1.03, per each year), greater education level (coefficient = 0.55 and OR= 1.74 for medium and coefficient = 1.05; OR = 2.57 for high level, compared with no education) and higher parity (coefficient= 0.26; OR = 1.30 per each previous offspring) increased the odds for having twins. Twins' male-male showed a slightly increased of preterm birth than a co-twin female. Opposite-sex twins showed measurable but small increases in birth weight and length compared with same-sex twins. Conclusion: The rate of twins in Yucatan increased substantially during 2008-2020 in specific sociodemographic groups. Opposite-sex twins were slightly larger than same-sex twins at birth.

Childhood acute lymphoblastic leukemia survival and spatial analysis of socio-environmental risks in Mexico.

Background: Acute lymphoblastic leukemia (ALL) etiology remains largely unknown; incidence patterns by age, sex, and geographical distribution suggest a potential environmental role. Aim: To identify ALL clusters from four contrasting urban areas of Mexico and to characterize the sources of environmental carcinogens. Methods: Hospital-based ALL cases (n = 443) diagnosed in children <19 years old from the Metropolitan Zones of Merida and San Luis Potosi, the State of Mexico, and Tijuana were analyzed (2015-2020). ALL cases were coded according to the International Classification of Diseases for Oncology. ALL clusters were identified by Kernel Density, and excess risk was estimated. Data of particulate matter ≤2.5 µm (PM2.5) concentrations measured by community-monitoring stations were analyzed. Geocoded datasets of benzene, polycyclic aromatic hydrocarbons, and PM2.5 sources were analyzed to characterize patterns of exposure in ALL clusters. Results: The survival rate for ALL ranged from 61.5% to 78.6%. Seven ALL clusters with excess risk (RR 1.4-2.3, p < 0.05) were identified. The carcinogen sources included artisanal brick kilns, gas stations, cement works, carpentry, paint, and chemical manufacturing establishments. PM2.5 levels ranged from 15 µg/m3 to 37 µg/m3 among study areas. Conclusion: ALL clusters were identified at the community level; the excess risk could be explained by small-scale carcinogen sources. The levels of PM2.5 in outdoor air ranged from 3 to 6 times above the World Health Organization (WHO) air quality guidelines. Healthcare providers must raise awareness of the increased risk of ALL in children living near sources of environmental carcinogens; cancer control and prevention strategies must be steered from a multi-sectoral and multi-action perspective to protect children's health.

Microwave-enhanced synthesis of 26-amino-22-oxocholestanes and their cytotoxic activity.

The synthesis of a series of 26-amino-22-oxocholestanes derived from diosgenin was accomplished via the substitution of an iodine atom at C-26 by primary and secondary amines. The reactions were conducted in refluxing acetonitrile and through microwave-assisted heating. The latter shows significant improvements in terms of reaction times going from hours to a few minutes or even seconds for completion. Only one of the selected amines, 4-aminourazole, did not yield the substitution product and the imine formation pathway was investigated instead, achieving the 26-iminourazole-22-oxocholestane. All the final products have been characterized and the cytotoxic activity of three of them has been evaluated in SiHa, MCF-7 and MDA tumor cell lines by the sulforhodamine B assay.

A Glycosaminoglycan-Rich Fraction from Sea Cucumber Isostichopus badionotus Has Potent Anti-Inflammatory Properties In Vitro and In Vivo.

Sea cucumber body wall contains several naturally occurring bioactive components that possess health-promoting properties. Isostichopus badionotus from Yucatan, Mexico is heavily fished, but little is known about its bioactive constituents. We previously established that I. badionotus meal had potent anti-inflammatory properties in vivo. We have now screened some of its constituents for anti-inflammatory activity in vitro. Glycosaminoglycan and soluble protein preparations reduced 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammatory responses in HaCaT cells while an ethanol extract had a limited effect. The primary glycosaminoglycan (fucosylated chondroitin sulfate; FCS) was purified and tested for anti-inflammatory activity in vivo. FCS modulated the expression of critical genes, including NF-ĸB, TNFα, iNOS, and COX-2, and attenuated inflammation and tissue damage caused by TPA in a mouse ear inflammation model. It also mitigated colonic colitis caused in mice by dextran sodium sulfate. FCS from I. badionotus of the Yucatan Peninsula thus had strong anti-inflammatory properties in vivo.

Long-lasting resistance to haloperidol-induced catalepsy in male rats chronically treated with caffeine.

Chronic caffeine consumption has been inversely associated with the risk of developing Parkinson's disease. Here we assessed whether chronic caffeine treatment increases the resistance of male Wistar rats to haloperidol (1mg/kg, s.c.)-induced catalepsy, measured in the bar test at 15 min intervals during 3h. Caffeine (5mg/kg/day) was delivered for 6 months via drinking water. Control rats received only tap water. Treatments began when animals were 3-4 months old. In order to unveil long-lasting catalepsy refractoriness not attributable to the presence of caffeine in the brains of rats, they were evaluated from day 18 to day 27 after caffeine withdrawal, a time that is far in excess for the full excretion of a caffeine dose in this species. The average cataleptic immobility measured in caffeine-treated rats (n=23) was 1148+/-140 s, a value 34+/-8% lower than that recorded in control animals (n=20), whose mean immobility was 1736+/-137 s (P=0.0026, t-test). The percentage of catalepsy reduction measured in caffeine-treated rats evaluated on days 18-20 after caffeine discontinuation (-32+/-13%, n=12, P<0.05) was comparable to the catalepsy decrease recorded in those animals tested on days 21-27 (-36+/-10%, n=11, P<0.02), a finding compatible with the notion that the effect was indeed mediated by enduring changes of brain functioning and not by the physical presence of caffeine or its metabolites. Caffeine-treated rats also had higher catalepsy latency scores compared with control rats (P<0.01, U-test). The present findings show that chronic consumption of caffeine produces perdurable resistance to catalepsy induced by dopamine receptor blockade, possibly through enhancement of dopamine transmission, giving further support to the epidemiological results indicating that prolonged caffeine consumption affords neuroprotection against Parkinson's disease.