Search Results (72)

With the first evidence of the association between bats and influenza A viruses, various studies have begun to emerge to understand this interesting and important association among bats conservation, animal health, and public health. This study aimed to verify the presence of anti-influenza A vipothesrus antibodies, as well as the molecular identification of these viruses in bats distributed in forest fragments located in southeastern Mexico. Blood samples were obtained from 600 bats belonging to 24 different species, using an enzyme immunoassay to detect antibodies against the nucleoprotein antigen of the avian influenza A virus. Likewise, oropharyngeal swabs, rectal swabs and organs were taken for quantitative reverse transcription PCR (qRT-PCR) of these viruses. A total of six bats (1%) tested positive either by serology or molecular methods, not both simultaneously. Although this suggests a very low prevalence of influenza A viruses in Mexican bats, it is the first study to address this association and, following the precautionary principle, we consider it necessary to establish systematic monitoring of the presence of influenza A in bats, since they are known to harbor infectious agents with zoonotic potential. Furthermore, it is possible that the association of influenza A viruses circulating in Latin American bats has an important co-evolutionary component with some bat species with exclusive distribution in the American continent. Full article

Ellis-van Creveld syndrome (EvC) is a rare genetic disorder (7:10,000,000) caused by biallelic pathogenic variants in EVC and EVC2, which are located in close proximity on chromosome 4p16.2 in a divergent orientation. These genes encode ciliary complex proteins essential for Hedgehog signaling. EvC is characterized by congenital heart disease (CHD), postaxial polydactyly, and rhizomelic shortening. We present a case of a female newborn from southeast Mexico carrying a novel missense variant in EVC, which is aligned with a systematic review aimed at exploring genotype–phenotype correlations in EVC-related EvC. A PRISMA-based systematic review was conducted in PubMed, Web of Science, and OVID/Medline (until December 2024). Studies reporting EVC variants in EvC were included. Data extraction and quality assessment were performed independently by four reviewers, and genotype–phenotype correlation analysis was conducted. Fifteen studies (n = 66 patients) met the inclusion criteria. The most prevalent features were postaxial polydactyly (95.5%), nail hypoplasia (68.2%), and CHD (66.7%) with atrioventricular canal as the most frequent subtype. Fifty-five distinct EVC variants across 132 alleles were identified, predominantly affecting the N-terminal region (first 699 amino acids). They were syndactyly correlated with pathogenic variants in exons 6, 12, and 13, which were proximal to the second and third coiled-coil domains. This review confirms the key clinical features of EVC-related EvC and highlights genetic heterogeneity. The correlation between syndactyly and specific exonic variants suggests potential genotype–phenotype associations, warranting further functional studies. Full article

Bagrada hilaris is an invasive stink bug causing important yield losses in Brassica crops. It originates from India, Southeast Asia, the Middle East and South Africa and is reported as invasive in several southwestern US states, Hawaii, Mexico, Chile and in the Mediterranean islands of Malta and Pantelleria (Italy). In this study, we tested the effects of gamma rays on the longevity, fecundity and fertility of bagrada bugs. We irradiated them at two different stages of their life cycle (fifth-instar nymphs and two-week-old adults). Irradiation at the nymphal stage had a strong impact on female fecundity, with egg numbers approaching zero at a dose of 80 Gy. Similarly, a full suppression of female fertility was achieved at 80 Gy when they were mated with males irradiated as nymphs or as mature adults. For longevity, gamma rays had only a slight impact on adult male and female life span. Due to the evidence of a gregarious phase during the autumn, these results suggest that small-scale SIT-localized applications by massive collections of bagrada bugs at various stages of development during autumn, followed by irradiation and reintroduction to the field, might be a safe and economically sound approach of control. Research is currently underway to evaluate the fitness of sterile males and mating patterns. Further studies in confined-field conditions will be needed. Full article

Bagrada hilaris (known as painted bug) is a pest native to India, Southeast Asia, and middle and central Africa and was reported as invasive in the southwestern USA, Hawaii, Mexico, South America, and two Mediterranean islands. The feeding activity results in extensive damage to economically important Brassicaceae crops. Among sustainable alternatives to synthetic pesticides, the Sterile Insect Technique (SIT) is considered a promising strategy because it relies on the release of competitive sterile males that can reduce the pest reproduction. In this study, the efficacy of different doses of gamma irradiation (60, 80, and 100 Gy) was evaluated to identify the treatment that would ensure high sterility without compromising the competitiveness of the treated males. Observational tests showed that the doses of 60 Gy and 80 Gy showed no difference in mating times compared to non-irradiated males, in contrast to 100 Gy. Thus, 80 Gy was identified as the most promising dose. For further investigation, tests were conducted under choice and no-choice conditions at 80 Gy for three days. The results showed that irradiated males had a comprehensive higher mating rate than non-irradiated males, and under choice conditions, they were often preferred by females, confirming that SIT has potential as an environment-friendly method for controlling B. hilaris. Full article

Citrus commercial species are the most important fruit crops in the world; however, their cultivation is seriously threatened by the fast dispersion of emerging diseases, including Huanglongbing (HLB) citrus greening. HLB disease is vectored by psyllid vectors and associated with phloem-limited α-proteobacteria belonging to the Candidatus Liberibacter genus. Climatic change and trade globalization have led to the rapid spread of HLB from its origin center in Southeast Asia, causing a great economic impact in the main production areas, including East Asia (China), the Mediterranean basin, North America (the United States), and Latin America (Brazil and Mexico). Despite important advances to understand the HLB epidemiology, Candidatus Liberibacter genetics, psyllid vector control, the molecular citrus–Candidatus Liberibacter interaction, and the development of integral disease management strategies, the study areas have been mostly restricted to high-tech-producing countries. Thus, in this review, we provide an overview of the epidemiology, distribution, genetic diversity, management aspects, and omics analysis of HLB in Latin America, where this information to date is limited. Full article

Mangroves and tropical swamp forests are ecosystems that play a critical role in carbon sequestration, coastal protection, and biodiversity support. Accurately estimating aboveground biomass (AGB) in these forests is crucial for global carbon management and conservation efforts. This study evaluates the potential of LiDAR-derived metrics to model the AGB of an area with mangroves and tropical swamp forests in Southeast Mexico. The study area, located in the Pantanos de Centla Protected Area, encompasses a gradient of seasonal waterlogged conditions, from saline to freshwater. Data were collected from 25 1250-m² plots, and three modeling approaches—linear regression, random forest, and XGBoost—were employed to estimate the AGB. The data were divided into training and test sets using an 80:20 ratio. The results indicate that the random forest model outperformed the others, achieving the lowest root mean squared error (RMSE = 20.25 Mg/ha, rRMSE = 12.25%, R² = 0.88). The most influential variables in this model were mean height (zmean), the 35th percentile of height (zq35), and the fourth percentile of returns (p4th), all positively correlated with the AGB. The model’s robustness and uncertainty were evaluated through bootstrapping and spatial prediction across the study area, with higher AGB values concentrated near the main water channels. This study underscores the effectiveness of LiDAR-derived metrics for AGB estimation in complex forested environments. Full article

In video-based fish surveys, species recognition plays a vital role in stock assessments, ecosystem analysis, production management, and protection of endangered species. However, implementing fish species detection algorithms in underwater environments presents significant challenges due to factors such as varying lighting conditions, water turbidity, and the diverse appearances of fish species. In this work, a transformer-enhanced YOLOv8 (YOLOv8-TF) is proposed for underwater fish species recognition. The YOLOv8-TF enhances the performance of YOLOv8 by adjusting depth scales, incorporating a transformer block into the backbone and neck, and introducing a class-aware loss function to address class imbalance in the dataset. The class-aware loss considers the count of instances within each species and assigns a higher weight to species with fewer instances. This approach enables fish species recognition through object detection, encompassing the classification of each fish species and localization to estimate their position and size within an image. Experiments were conducted using the 2021 Southeast Area Monitoring and Assessment Program (SEAMAPD21) dataset, a detailed and extensive reef fish dataset from the Gulf of Mexico. The experimental results on SEAMAPD21 demonstrate that the YOLOv8-TF model, with a mean Average Precision (mAP)_0.5 of 87.9% and mAP_0.5–0.95 of 61.2%, achieves better detection results for underwater fish species recognition compared to state-of-the-art YOLO models. Additionally, experimental results on the publicly available datasets, such as Pascal VOC and MS COCO datasets demonstrate that the model outperforms existing approaches. Full article

The Calakmul Biosphere Reserve (CBR) is in the south of the Yucatán Peninsula and is known for its great biological diversity. However, despite the great diversity of species, they are under intense pressure from hunting activities, especially the larger ones that can be used for human food. Therefore, the objective of this study was to obtain knowledge about the hunting importance of populations of three species of birds (Crax rubra, Meleagris ocellata, and Penelope purpurascens) in the southern zone of the Calakmul Biosphere Reserve, Campeche. Sampling was conducted with transects where a total of 46 camera traps were installed from November 2021 to November 2022, distributed in two types of vegetation. Likewise, data on species presence were collected and analyzed with Principal Component Analysis and ANOSIM (ANOSIM; R = 0.10, p = 0.22) to relate abundances with vegetation types and seasons of the year. No significant differences were found between the two vegetation types. This study provides relevant information on the populations of game birds in the southern region of Calakmul, which is currently little explored, and constant monitoring of these species throughout the CBR is necessary. Full article

Lake Bacalar, a fragile oligotrophic ecosystem located in the southeast of Yucatan Peninsula, Mexico, suffered from a sudden brownification after the tropical storm Cristobal in June 2020 in the Gulf of Mexico. The color change was the most visible effect of the storm, but all other water variables changed towards eutrophication. We used light traps and DNA barcoding of the zooplankton specimens based on previous baseline constructed for comparison with the species found after the change. A dramatic shift in the zooplankton community occurred: biomass was reduced to a minimum and 20 species of water mites, five copepods, three cladocerans, three chironomids and six species of fish larvae disappeared for a period of at least one year. They were replaced by three species of water mites, four cladocerans, one copepod, 23 chironomids and one ephemeropteran previously not registered, most of the species being characteristic of more eutrophic environments. The southernmost part of the lake, Laguna Xul-Ha, which conserved its oligotrophic characteristics, apparently became a refuge for the original fauna from the whole system. The ecosystem did not fully recover to its original condition until about two years later. While the system has returned to its original state after the storm described here, future changes in land use, including unsustainable tourism expansion, may compromise its resilience and induce hysteresis. Full article

Mangroves are essential for the well-being of the inhabitants of coastal areas, who have extensive knowledge about the use and exploitation of this resource. However, this knowledge is decreasing, which could trigger negative repercussions for this ecosystem. Ethnobiological investigations make it possible to gather information on the use, management, and exploitation of this resource. Hence, this paper presents a study that is framed around the coastal area of the state of Tabasco, in southeast México, and consists of 74 semi-structured interviews that were carried out, while the local relevance of each mangrove species was evaluated using ethnobiological indices. Three species of mangrove were identified, Avicennia germinans, Laguncularia racemosa, and Rhizophora mangle, and the latter species had the highest Use-Value (UV) Index value of 6.08. A total of 27 forms of forestry use were found, 11 for non-timber use and 16 for timber use. Firewood stood out as the main use with 12.6%, while the use of needles to make cloth and crafts represented the lowest percentage with 0.3%. The uses given by the coastal population to the mangroves and their respective species were influenced by immediate needs and specific characteristics of each species. To ensure the sustainability of mangroves, it is essential to design environmental strategies that integrate local ethnobiological knowledge and promote the active participation of direct users of this ecosystem. These strategies should be incorporated into public conservation policies, recognizing the cultural and economic value that mangroves hold for local communities. By implementing these actions, the relationship between communities and their environment will be strengthened, laying the groundwork for further exploration of coastal ethnobiology. Full article

The Tula industrial area in Central Mexico comprises, among other industries, a refinery and a thermoelectric power plant. It is well known for its constant emissions of gases into the atmosphere and considered an important area where pollutants released into the atmosphere have an influence on local and regional air quality. During March and April 2017, a field campaign was conducted with the objective of quantifying formaldehyde (HCHO), sulfur dioxide (SO₂), and nitrogen dioxide (NO₂) emissions from this industrial area using mobile differential optical absorption spectroscopy (DOAS) instruments. Calculated average emissions of the Francisco Perez Rios Power Plant and the Miguel Hidalgo Refinery were 3.14 ± 2.13 tons per day of HCHO, 362.08 ± 300.14 tons per day of SO₂, and 24.76 ± 12.82 tons per day of NO₂. From the measurements conducted, the spatial distribution patterns of SO₂, NO₂, and HCHO were reconstructed, showing a dispersion pattern of SO₂ and NO₂ towards the southwest of the industrial complex, impacting agricultural and urban areas. Occasionally, and usually during the morning hours, SO₂ and NO₂ were dispersed towards the north or northeast of the industrial complex. In the case of HCHO, dispersion was observed towards the south and southeast of the industrial complex. The far-reaching implications of this study are that for the first time, formaldehyde emissions were quantified. In addition, a follow-up study was conducted regarding nitrogen dioxide and sulfur dioxide emissions from the Tula Industrial area. Full article

In Mexico, breast cancer (BC) is the principal cause of death in women over 30 years old, with an annual mortality rate of 14.61 deaths per a 100,000 population. Chemotherapy, in combination with trastuzumab (TTZ), improves the survival of cancer patients; however, cardiotoxicity (CT) is the principal consequence. CT prevalence occurs between 10% and 30% of patients; however, there are no data about the prevalence of CT in the Mexican population. This study aims to establish the prevalence of CT in patients treated with anti-HER-2 therapy among BC women in southeast Mexico. A retrospective cross-sectional study was carried out from January 2015 to July 2019. The records of 46 patients diagnosed with HER-2-positive BC who attended the Mexican Social Security Institute in the Ambulatory Care Medicine Unit were analyzed. The diagnostic criterion for CT was a decrease in LVEF > 10% from baseline or a final LVEF < 53%. CT prevalence was observed in 19 (41.3%) of women with cancer, with an average decrease in LVEF of 13%. In the population, we found an association between weight, surface area, and the loading dose of TTZ with CT. Nutritional follow-up and the administration of cardioprotective drugs are necessary to recover LVEF and avoid cardiovascular failure in women with BC and survivors. Full article

The April 2010 earthquake (Mw = 7.2), which occurred about 40 km to the southeast of the city of Mexicali, Mexico, caused significant damage to buildings. To improve knowledge of the seismic response of the soil due to the occurrence of earthquakes, a response spectrum at 5% damping was calculated. A comparison between the spectral ordinates obtained in this study and the spectra proposed by the regulations of the Federal Electricity Commission (CFE for its acronym in Spanish) in its seismic design for civil works manual, which is currently used as the design standard throughout the country, was made. We calculated response spectra using records from the April 2010 earthquake and a stratigraphic profile of the city to calculate a transfer function. We first corrected the records for site effect due to stations being over sedimentary soil, and then used them as Green functions to perform a numerical simulation of propagation through the stratigraphic profile to obtain a simulated surface record from which response spectra were calculated. Additionally, ambient seismic noise was measured at the same site to get the dominant period (To). We observed that the transfer function was similar to the spectral quotient up to 5 Hz and that To calculated in both ways gave similar values. The comparison suggests that the design spectrum of the CFE regulation can be considered as a representative spectrum for Mexicali for periods greater than 1.3 s, but not for the zone of short periods. Full article

Chysobalanus icaco L. (C. icaco) is a plant that is native to tropical America and Africa. It is also found in the southeast region of Mexico, where it is used as food and to treat certain diseases. This study aimed to carry out a phytochemical analysis of an aqueous extract of C. icaco seed (AECS), including its total phenol content (TPC), total flavonoid content (TFC), and condensed tannins (CT). It also aimed to examine the antioxidant and metal-ion-reducing potential of the AECS in vitro, as well as its toxicity and anti-inflammatory effect in mice. Antioxidant and metal-ion-reducing potential was examined by inhibiting DPPH, ABTS, and FRAP. The acute toxicity test involved a single administration of different doses of the AECS (0.5, 1, and 2 g/kg body weight). Finally, a single administration at doses of 150, 300, and 600 mg/kg of the AECS was used in the carrageenan-induced model of subplantar acute edema. The results showed that the AECS contained 124.14 ± 0.32 mg GAE, 1.65 ± 0.02 mg EQ, and 0.910 ± 0.01 mg of catechin equivalents/g dried extract (mg EC/g de extract) for TPC, TFC and CT, respectively. In the antioxidant potential assays, the values of the median inhibition concentration (IC₅₀) of the AECS were determined with DPPH (0.050 mg/mL), ABTS (0.074 mg/mL), and FRAP (0.49 mg/mL). Acute toxicity testing of the AECS revealed no lethality, with a median lethal dose (LD₅₀) value of >2 g/kg by the intragastric route. Finally, for inhibition of acute edema, the AECS decreased inflammation by 55%, similar to indomethacin (59%, p > 0.05). These results demonstrated that C. icaco seed could be considered a source of bioactive molecules for therapeutic purposes due to its antioxidant potential and anti-inflammatory activity derived from TPC, with no lethal effect from a single intragastric administration in mice. Full article

Even though the role of ecosystem services is known, the identification and assessment of water-related services is usually absent or often less represented as an ecosystem service. Progress in water quality indicator definition and compliance with regulations has been made; however, the relationship between water quality degradation and benefits to individuals and ecosystems remains little recognized. Here, we present an assessment of water quality and identification of ecosystem services in south-east Mexico. This study was performed within the geohydrological reserve zone of the Ring of Sinkholes, Yucatán Peninsula. Thirteen ecosystem services provided by the aquifer were identified. Water quality was evaluated in sinkholes based on national and international norms, considering different sinkhole uses. Results show a dynamic system, without saltwater intrusion and good to excellent water quality. The research demonstrates the relationship between ecosystem services and water quality, showing pressure in services related to uses for aquatic life protection and to a lesser extent those related to consumption. Current productive activities showed no pressure at this time. Principal Component Analysis (PCA) and Analysis of Variance (ANOVA) exhibited a significant difference in parameters and campaigns, but not between sinkholes. A long-lasting monitoring program for water quality is necessary to accurately evaluate the status of ecosystem services provided by the aquifer. Moreover, it is necessary to assess aquifers as ecosystems with economic, ecologic and socio-cultural importance. Effective water governance requires a balance of interests between all parties, within a legal and institutional framework. Full article