Regions Of Central America Research Articles

Dog ectoparasites as sentinels for pathogenic Rickettsia and Bartonella in rural Guatemala

Fleas and ticks serve as vectors of multiple pathogens in the genera Rickettsia and Bartonella that cause diseases in humans and other animals. Although human rickettsiosis and bartonellosis have been reported in all countries in Central America, limited research has been conducted to investigate the natural cycles of flea- and tick-borne rickettsiosis and bartonellosis, especially in Guatemala. We evaluated dog parasites as sentinels for zoonotic disease risk in rural Guatemala by sampling ticks and fleas from dogs, which were then identified and individually screened for Rickettsia and Bartonella. A total of 77 households were surveyed and 80.5 % of them had dogs. Overall, 133 dogs were examined for fleas and ticks, of which 68.4 % had fleas and 35.3 % had ticks. A total of 433 fleas and 181 ticks were collected from the infested dogs, with an additional 33 ticks collected from house walls. Three flea species were identified: Ctenocephalides felis (70.0 %), Echidnophaga gallinacea (11.8 %), and Pulex sp. (17.8 %). Among the collected ticks, 97 % were identified as Rhipicephalus sanguineus sensu lato with the rest being Amblyomma cajennense, A. auricularium, and A. ovale. Rickettsia felis were detected in six C. felis, in one Pulex sp., and in two R. sanguineus sensu lato, while Candidatus R. senegalensis was detected in one C. felis. Bartonella was detected only in fleas, including three Pulex sp. infected with B. vinsonii subsp. berkhoffii, B. henselae, and Bartonella sp., respectively, and 11 C. felis infected with B. henselae. This study reports Candidatus R. senegalensis and B. vinsonii subsp. berkhoffii in Guatemala for the first time, and indicates the potential risk of human and dog exposure to Rickettsia and Bartonella species. These results show that dogs provide critical information relevant to managing human potential exposure to flea- and tick-borne pathogens in rural Guatemala. This approach can potentially be expanded to other regions in Central America where domestic dogs are abundant and suffer from ectoparasite infestation.

Flavonoid quantitative HPLC-DAD analysis of Petiveria alliacea

Petiveria alliacea L. (Petiveriaceae), a medicinal plant found in tropical regions of South and Central America, the Caribbean, and Africa, is mainly used to treat inflammatory process and respiratory problems. In this study, we have evaluated the antibacterial activity of P. alliacea crude extract and fractions, investigated the chemical composition, and developed and validated a simple method to quantify flavanones. To verify the antibacterial activity, we determined the minimum inhibitory concentration (MIC) against Staphylococcus aureus and Escherichia coli. Phytochemical investigations were carried out by chromatographic and spectroscopic analysis. To quantify astilbin and engeletin, we developed a method based on HPLC coupled to a diode array detector (DAD) and validated it. The P. alliacea crude extracts and fractions exhibited MIC ranged from 10 to 25 mg/mL. Chemical investigation of P. alliacea revealed the presence of trans-N-methyl-4-methoxyproline (1), ethyl-β-galactoside (2), ethyl-α-galactoside (3), and ethyl-β-fructofuranoside (4). The developed HPLC-DAD method proved suitable for determining flavonoids in P. alliacea: it presented good linearity, specificity, and satisfactory accuracy and precision. The developed HPLC-DAD method can quantify the P. alliacea chemical markers. The isolated compounds (2–4) have been described in P. alliacea for the first time.

Worldwide Research Trends and Networks on Flood Early Warning Systems

This review paper examined the global landscape of research on continental flood early warning systems (EWS), shedding light on key trends, geographic disparities, and research priorities. Continental floods stand as one of the most pervasive and devastating disasters worldwide, necessitating proactive measures to mitigate their impact. Drawing upon a comprehensive analysis of the scholarly literature indexed in the Web of Science repository, this study unveiled significant patterns in EWS research. While the emphasis on flooding is evident, a considerable portion of research focuses on precipitation as a variable and modeling approaches. Furthermore, the influence of climate change emerges as a prominent theme, though distinguishing between climate change and variability remains a crucial area for exploration. Geographically, Europe, particularly England and Italy, dominates research efforts in flood related EWS. Conversely, the limited representation of Central America and other regions such as Asia and Oceania, underscores the need for greater attention to regions facing significant flood risks. Importantly, the concept of total link strength emerges as a valuable metric, highlighting collaborative networks established by European countries and the United States. Based on these findings, recommendations are proposed to enhance the inclusivity and effectiveness of flood related EWS research, including a broader consideration of socio-economic factors, fostering collaboration among researchers from diverse regions, and prioritizing initiatives to strengthen research capacities in vulnerable areas. Ultimately, this study provides valuable insights for policymakers, researchers, and practitioners seeking to advance flood risk management strategies on a global scale.

A comparative analysis reveals the genomic diversity among 8 Muscovy duck populations.

The Muscovy duck (Cairina moschata) is a waterfowl indigenous to the neotropical regions of Central and South America. It has low demand for concentrated feed and strong adaptability to different rearing conditions. After introduced to China through Eurasian commercial trade, Muscovy ducks have a domestication history of around 300 years in the Fujian Province of China. In the 1990s, the commodity Muscovy duck breed "Crimo," cultivated in Europe, entered the Chinese market for consumption and breeding purposes. Due to the different selective breeding processes, Muscovy ducks have various populational traits and lack transparency of their genetic background. To remove this burden in the Muscovy duck breeding process, we analyzed genomic data from 8 populations totaling 83 individuals. We identify 11.24 million single nucleotide polymorphisms (SNPs) and categorized these individuals into the Fujian-bred and the Crimo populations according to phylogenetic analyses. We then delved deeper into their evolutionary relationships through assessing population structure, calculating fixation index (FST) values, and measuring genetic distances. Our exploration of runs of homozygosity (ROHs) and homozygous-by-descent (HBD) uncovered genomic regions enriched for genes implicated in fatty acid metabolism, development, and immunity pathways. Selective sweep analyses further indicated strong selective pressures exerted on genes including TECR, STAT2, and TRAF5. These findings provide insights into genetic variations of Muscovy ducks, thus offering valuable information regarding genetic diversity, population conservation, and genome associated with the breeding of Muscovy ducks.

Chemical composition and antimicrobial activity of an apolar extract from Lactuca serriola L. leaves

Lactuca serriola L. is an annual herbaceous plant species belonging to the Asteraceae family, called Prickly lettuce, Wild lettuce, and Jagged lettuce. L. serriola grows on grassy and rocky slopes in many regions in Europe, Asia, Australia, Africa, and North, Central and South America. The plant is used as a natural pharmaceutical agent in primary health care due to its analgesic, anti-inflammatory, antibacterial, and antioxidant properties, which are attributed to the compounds it contains. However, this is the first study demonstrating the antimicrobial activity of L. serriola essential oil. In this study, L. serriola essential oil was obtained by hydrodistillation of plant leaves and analyzed by Gas Chromatography-Mass Spectrometry (GS-MS); subsequently, antimicrobial properties of the essential oil were evaluated using agar dilution and broth microdilution methods. As a result of the GS-MS analysis, hexadecanoic acid, oleic acid, myristic acid, hexahydrofarnesyl acetone, β-ionone, and n-tetradecyl butanoate were found as dominant components in the plant essential oil with the rate of 6.61%, 4.84%, 2.05, 1.55%, 1.3%, and 1.09% (v/v), respectively. The MIC value of L. serriola essential oil against Enterobacter aerogenes,Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans, and Candida tropicalis was found to be 0.94 μLmL−1, and MIC values were determined as 1.87 μLmL−1 and 0.47 μLmL−1 against Klebsiella pneumonia and Candidaparapsilosis, respectively. These results have opened a new horizon regarding the usability of L. serriola essential oil as a pharmacological therapeutic antibacterial and antifungal agent.

Factors Associated with the Prevalence of Bovine Tuberculosis in the Kafue Basin of Zambia

Worldwide, bovine tuberculosis is most common in agricultural regions of Central and South America, Sub-Saharan Africa and South-Western Asia. Bovine tuberculosis was reported to be endemic in the Zambian traditional cattle sector with a high herd prevalence of 49.8% recorded from areas within, and adjacent to the Kafue Basin as far back as 1995. An analytical cross sectional study design was applied to a sample size of 384 selected cattle owners in the Kafue Basin. A semi-structured questionnaire was administered to the cattle owners who were randomly selected. The data was analyzed using STATA Version 15 Software. The results from the study showed that 54% of the cattle owners experienced bovine tuberculosis among their cattle while 46% did not experience bovine tuberculosis. The prevalence of bovine tuberculosis in cattle was higher among the male cattle owners (76%) compared to female cattle owners (24%). There was a significant relationship of p value < 0.029 between level of knowledge of cattle owners and the prevalence of bovine tuberculosis. Unemployed cattle owners had higher odds of experiencing bovine tuberculosis among their cattle (OR 3.488; 95% CI 1.341-9.067) and the relationship was statistically significant at p value < 0.010. There was equally a significant relationship of p value < 0.042 between vaccination status of animals and the occurrence of bovine tuberculosis. The study showed that the majority of cattle owners lacked awareness and had a lower level of understanding of the disease and its public health significance. Therefore, the implications of the study suggest the creation of disease control programs that will ensure regular herd testing for bovine tuberculosis, routine vaccinations of animals, deliberate quarantine of infected animals as well as community health education about transmission, control and prevention of the disease.

Spatial phylogenetics of Fagales: Investigating drivers of temperate forest distributions

AbstractAimQuantifying the phylogenetic diversity of temperate trees is essential for understanding the processes that have shaped the modern distribution of temperate broadleaf forest and other major forest biomes. Here, we focus on Fagales, an iconic member of forests worldwide, to uncover global diversity and endemism patterns and investigate the distribution of root nodule symbiosis (RNS), an important morphological specialisation in this clade, as a key factor behind these patterns.LocationGlobal.TaxonFagales.MethodsWe combined phylogenetic data covering 60.2% of living species, fine‐scale distribution models covering 90% of species, and nodulation data covering all species to investigate the distribution of species richness and phylogenetic diversity at fine spatial scales compared to the distribution of RNS. We identify abiotic environmental factors associated with RNS and with Fagales diversity in general.ResultsWe find the highest species richness in temperate east Asia, eastern North America, and equatorial montane regions of Asia and Central America. By contrast, relative phylogenetic diversity (RPD) is highest at higher latitudes, where RNS also predominates. We found a strong spatial structuring of regionalisations of Fagales floras, reflecting distinct Northern and Southern Hemisphere floras (except a unique Afro‐Boreal region), each with distinct RNS‐environment relationships.Main ConclusionsAlthough species richness and phylogenetic regionalisation for Fagales accord well with traditional biogeographic concepts for temperate forests, this is not the case for RPD. RNS is almost universal in the highest RPD regions, which may reflect ecological filtering promoting RNS in these regions. Our results highlight the utility of global‐scale, clade‐specific spatial phylogenetics and its utility for understanding drivers of diversity in species‐rich clades.

Exploring Four Atraphaxis Species: Traditional Medicinal Uses, Phytochemistry, and Pharmacological Activities.

Atraphaxis is a genus of flowering plants in the family Polygonaceae, with approximately 60 species. Species of Atraphaxis are much-branched woody plants, forming shrubs or shrubby tufts, primarily inhabiting arid zones across the temperate steppe and desert regions of Central Asia, America, and Australia. Atraphaxis species have been used by diverse groups of people all over the world for the treatment of various diseases. However, their biologically active compounds with therapeutic properties have not been investigated well. Studying the biologically active components of Atraphaxis laetevirens, Atraphaxis frutescens, Atraphaxis spinosa L., and Atraphaxis pyrifolia is crucial for several reasons. Firstly, it can unveil the therapeutic potential of these plants, aiding in the development of novel medicines or natural remedies for various health conditions. Understanding their bioactive compounds enables scientists to explore their pharmacological properties, potentially leading to the discovery of new drugs or treatments. Additionally, investigating these components contributes to preserving traditional knowledge and validating the historical uses of these plants in ethnomedicine, thus supporting their conservation and sustainable utilization. These herbs have been used as an anti-inflammatory and hypertension remedies since the dawn of time. Moreover, they have been used to treat a variety of gastrointestinal disorders and problems related to skin in traditional Kazakh medicine. Hence, the genus Atraphaxis can be considered as a potential medicinal plant source that is very rich in biologically active compounds that may exhibit great pharmacological properties, such as antioxidant, antibacterial, antiulcer, hypoglycemic, wound healing, neuroprotective, antidiabetic, and so on. This study aims to provide a collection of publications on the species of Atraphaxis, along with a critical review of the literature data. This review will constitute support for further investigations on the pharmacological activity of these medicinal plant species.

Review of the globally invasive freshwater mussels in the genus Sinanodonta Modell, 1945

AbstractIn this review, we synthesize the current knowledge of the biology, ecology, and impact of Sinanodonta freshwater mussels (Bivalvia, Unionidae), native to East Asia, that have successfully invaded Europe, Central America, North Africa, and several Asian regions. The main introduction pathways of Sinanodonta were reconstructed based on DNA sequence data and distribution records. We show that invasive lineages of Sinanodonta belong to three species, namely, S. woodiana s. str. (“temperate invasive” lineage), S. pacifica (“tropical invasive” lineage), and S. lauta. Their generalist fish-dispersed larvae, short life span, high fecundity, use by humans for multiple purposes, and ability to establish populations in anthropogenically disturbed conditions were identified as crucial traits driving their invasions. Information on the consequences is scarcer, but Sinanodonta can impact native species through larval parasitism, host fish/food competition, and parasite transmission. In addition, ecosystem effects through their filtration—biodeposition—excretion activity and the occurrence of massive die-offs were detected. Ecosystem services and disservices have not yet been quantified, even at local scales, and management methods in the invasive range are understudied. A better understanding of Sinanodonta ecology, impacts, and management options is urgently needed to make informed decisions and set realistic and impactful restoration goals.

Novel species of Triatoma (Hemiptera: Reduviidae) identified in a case of vectorial transmission of Chagas disease in northern Belize

Chagas disease is a leading cause of non-ischemic cardiomyopathy in endemic regions of Central and South America. In Belize, Triatoma dimidiata sensu lato has been identified as the predominate taxon but vectorial transmission of Chagas disease is considered to be rare in the country. We recently identified an acute case of vector-borne Chagas disease in the northern region of Belize. Here we present a subsequent investigation of triatomines collected around the case-patient’s home. We identified yet undescribed species, closely related to Triatoma huehuetenanguensis vector by molecular systematics methods occurring in the peridomestic environment. The identification of a T. cruzi-positive, novel species of Triatoma in Belize indicates an increased risk of transmission to humans in the region and warrants expanded surveillance and further investigation.

Electrophysiological evaluation of the effect of peptide toxins on voltage-gated ion channels: a scoping review on theoretical and methodological aspects with focus on the Central and South American experience.

The effect of peptide toxins on voltage-gated ion channels can be reliably assessed using electrophysiological assays, such as the patch-clamp technique. However, much of the toxinological research done in Central and South America aims at purifying and characterizing biochemical properties of the toxins of vegetal or animal origin, lacking electrophysiological approaches. This may happen due to technical and infrastructure limitations or because researchers are unfamiliar with the techniques and cellular models that can be used to gain information about the effect of a molecule on ion channels. Given the potential interest of many research groups in the highly biodiverse region of Central and South America, we reviewed the most relevant conceptual and methodological developments required to implement the evaluation of the effect of peptide toxins on mammalian voltage-gated ion channels using patch-clamp. For that, we searched MEDLINE/PubMed and SciELO databases with different combinations of these descriptors: "electrophysiology", "patch-clamp techniques", "Ca2+ channels", "K+ channels", "cnidarian venoms", "cone snail venoms", "scorpion venoms", "spider venoms", "snake venoms", "cardiac myocytes", "dorsal root ganglia", and summarized the literature as a scoping review. First, we present the basics and recent advances in mammalian voltage-gated ion channel's structure and function and update the most important animal sources of channel-modulating toxins (e.g. cnidarian and cone snails, scorpions, spiders, and snakes), highlighting the properties of toxins electrophysiologically characterized in Central and South America. Finally, we describe the local experience in implementing the patch-clamp technique using two models of excitable cells, as well as the participation in characterizing new modulators of ion channels derived from the venom of a local spider, a toxins' source less studied with electrophysiological techniques. Fostering the implementation of electrophysiological methods in more laboratories in the region will strengthen our capabilities in many fields, such as toxinology, toxicology, pharmacology, natural products, biophysics, biomedicine, and bioengineering.

Primeiro registro de Aricoris campestris (Bates, 1868) Lepidoptera: Riodinidae em pitaya no nordeste brasileiro

ABSTRACT Pitaya (Selenicereus spp.) is a tropical fruit tree belonging to the Cactaceae family, native to the tropical regions of Central and South America. Your cultivation has been considered promising due to its organoleptic characteristics and its high acceptance in the market. However, little information is available about pests associated with pitaya in northeastern Brazil. Here, we aim to communicate the identification and record of the occurrence of a pest insect in a pitaya plantation in the Caatinga. Caterpillars of this lepidopteran were collected from parts of pitaya plants, in January 2021, in the municipality of São João do Cariri, PB (7° 23'27” S, 36°31'57” W), placed in plastic containers and transported to the Invertebrates Laboratory of the Biosciences Department at the Agricultural Sciences Center of the Federal University of Paraíba, in the municipality of Areia, PB. Under laboratory conditions, the caterpillars were fed with pitaya shoots and kept in an environment with controlled conditions of temperature and humidity. When they reached the pupal stage, they were transferred to a cage and kept until the adults emerged. Identification of the adult was carried out by a specialist, by comparison with specimens from the Reference Collection of the Laboratory of Ecology and Interactions of Insects of the Caatinga (CLEIIC), belonging to the Federal University of Campina Grande, Patos, PB. The lepidopteran is Aricoris campestris (Bates, 1868), belonging to the Riodinidae family, Nymphidiini tribe, which also attacks other cacti in the region and has already been recorded in other areas in northeastern Brazil.

Hepatitis E infection: A review.

Hepatitis E virus (HEV) is a small non-enveloped virus that is transmitted via the fecal-oral route. It is a highly common cause of acute hepatitis, particularly in low to middle income regions of Asia, Africa, and Central America. Most cases are self-limited, and symptomatic patients usually present with acute icteric hepatitis. A subset of patients including pregnant women, older men, those with pre-existing liver disease and immunocompromised patients however, may develop severe disease and hepatic failure. Immunocompromised patients are also at risk for chronic infection, and their immunosuppression should be decreased in order to facilitate viral clearance. HEV can also present with a variety of extra-intestinal manifestations including neurological, renal, hematological, and pancreatic derangements. The gold standard of diagnosis is HEV ribonucleic acid detection via nucleic acid amplification testing. Currently, there are no approved treatments for Hepatitis E, though ribavirin is the most commonly used agent to reduce viral load. Studies assessing the safety and efficacy of other antiviral agents for HEV are currently underway. HEV vaccination has been approved in China, and is currently being investigated in other regions as well. This review article aims to discuss the epidemiology, pathogenesis, presentation, diagnosis, complications, and treatment of Hepatitis E infection.

Fall armyworm, Spodoptera frugiperda (J.E. Smith) damage on rice in the Philippines

Fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) is a global invasive pest of corn, and is also common on sorghum, rice and millets, and is reported to be a larval host of 353 cultivated and uncultivated plants . FAW, a native to the tropical and subtropical regions of north, Central, and South America, continues to rapidly spread to Africa and Asia since 2016, threatening food security worldwide . In the Philippines, its first damage on corn was reported in June 2019 in Piat, Cagayan , while that on rice was in May 2021 in Gonzaga, Cagayan, and subsequently to other municipalities in Region 2 . Unlike corn, however, little is known about FAW damage and host preference for rice in the Philippines. Rice, a key food security crop for the Philippines and in Asia, is amongst the key host of the FAW elsewhere (e.g., USA) . The injury that the FAW will inflict in the rice plant should be known and assessed to quantify the potential yield losses, and predict when an intervention is necessary to avoid incurring potential yield losses. With this background, we conducted FAW monitoring and damage assessment in the areas reported to have FAW occurrence starting May 2021. During 2021 and 2022 assessment periods, monitoring was conducted during the months of May, June, and July. However, starting January 2023, the monitoring and damage assessments were conducted monthly with the exception for May and June wherein it was done weekly since these months coincided with the seedling stage of the rice in a majority of rice-growing areas in the Philippines and where FAW attack was reported during the previous years. FAW larval population and damage were assessed in rice seedbeds. The number of FAW larvae were counted and visual damage was estimated in a 1 m2 quadrat with three replicates.

Inferring multiple coffee flowerings in Central America using farmer data in a probabilistic model

Coffee (Coffea arabica L.) is a climate-sensitive crop; rainfalls may trigger flowering event occurrences, and extreme rainfall during a flowering day can cause considerable yield reductions. Multiple flowering events can occur in the span of 12 months; the number varies from year to year. This paper introduces a Bayesian network model capable of inferring coffee flowering events in coffee areas in the Pacific Region of Central America based on observed data for coffee flowering and precipitation. The model structure was determined based on expert knowledge, and the model parametrization was learned from 53 years of data registered in the region. Data from four farms in the region were used for model validation. The model's performance in the inference of flowering intensity was good (spherical payoff of 0.78 out of maximal 1.00), and the model was able to depict expected behaviors for single and multiple flowerings. Further, comprehensive new details on the dynamics of multiple flowerings within a crop season were obtained, e.g., that a large flowering event tends to occur more quickly (8 to 10 days) after rain than a small flowering (10 to 13 days). We believe that this Bayesian network model has the potential to evolve and support the development of agricultural index-based insurance to deal with yield losses due to extreme rainfall during flowering. The use of longer farm records for model building may also serve to increase farmers' trust in the reliability of the tool.

Central America and the Dominican Republic at Crossroads: The Importance of Regional Cooperation and Health Economic Research to Address Current Health Challenges

ObjectivesWe discuss key health challenges currently faced by countries in the Central America and Dominican Republic region after the COVID-19 pandemic. We highlight the influence of socioeconomic determinants for the challenging public health dynamics observed and the crucial roles that regional cooperation and health economic research can have for tackling such challenges. MethodsWe present a descriptive overview of the current situation of public finances and its effect on government capacity to improve social expenditure. We also discuss the impact of the COVID-19 pandemic crisis on social dynamics and living conditions in the region. ResultsOur analysis suggests that the interplay between all these factors is likely to have important consequences for health systems and population health in the post-pandemic period. Previous examples of successful cross-country cooperation in the region indicate the great potential that these initiatives have for supporting health system resilience against current challenges. Technical cooperation must be informed by (currently unavailable) research evidence that can guide decision making, especially health economic research to support national health resource allocation policies. Areas identified as priorities for applied health economic research include both macro and microeconomic analyses. ConclusionsCentral America and the Dominican Republic face significant health challenges post-pandemic. Our article emphasizes the great potential that regional technical cooperation, informed by further health economic research, has to improve public policies and health governance in the region.

Extraction, structural properties, and bioactivities of Moringa (Moringa oleifera Lam.) isothiocyanates: A review

Moringa, a medicinal and edible plant, is rich in extremely high levels of nutrients and several active ingredients. Moringa isothiocyanates (MITC) are the key bioactive components of Moringa, which could be utilized in the food and pharmaceutical industries. This review aims to highlight the research progress in the extraction methods, isolation and purification processes of MITC. The structure properties of MITC and the metabolism of the compounds are described in detail. The bioactivities of MITC are summarized as anti-inflammatory, anticancer, antibacterial, antidiabetic, neuroprotective, relieve pain, anti-obesity potential, and other activities. In order to bring MITC into the food and pharmaceutical fields as early as possible, bioavailability, safety and toxicity deserve high attention. Therefore, six sections are reviewed in terms of extraction, structural properties, bioactivity, structure-bioactivity and bioavailability relationships of MITC, safety and toxicity, and applications in food and biomedical industries. It is expected that the mass production of MITC, which originated in India and is distributed in tropical and subtropical regions of Asia, Africa, and Central America, will be achieved on a larger scale and that new insights will be gained for the development of new resource foods and new clinical drugs.

Exploring structural antigens of yellow fever virus to design multi-epitope subunit vaccine candidate by utilizing an immuno-informatics approach

BackgroundYellow fever is a mosquito-borne viral hemorrhagic disease transmitted by several species of virus-infected mosquitoes endemic to tropical regions of Central and South America and Africa. Earlier in the twentieth century, mass vaccination integrated with mosquito control was implemented to eradicate the yellow fever virus. However, regular outbreaks occur in these regions which pose a threat to travelers and residents of Africa and South America. There is no specific antiviral therapy, but there can be an effective peptide-based vaccine candidate to combat infection caused by the virus. Therefore, the study aims to design a multi-epitope-based subunit vaccine (MESV) construct against the yellow fever virus to reduce the time and cost using reverse vaccinology (RV) approach. MethodsYellow fever virus contains 10,233 nucleotides that encode for 10 proteins (C, prM, E, NS1, NS2A, NS2B, NS3, NS4A, NS4B, and NS5) including 3 structural and 7 non-structural proteins. Structural proteins—precursor membrane protein (prM) and envelope protein (E)—were taken as a target for B cell and T cell epitope screening. Further, various immunoinformatics approaches were employed to FASTA sequences of structural proteins to retrieve B cell and T cell epitopes. MESV was constructed from these epitopes based on allergenicity, antigenicity and immunogenicity, toxicity, conservancy, and population coverage followed by structure prediction. The efficacy of the MESV construct to bind with human TLR-3, TLR-4, and TLR-8 were evaluated using molecular docking and simulation studies. Finally, in-silico cloning of vaccine construct was performed withpBR322 Escherichia coli expression system using codon optimization. ResultsPredicted epitopes evaluated and selected for MESV construction were found stable, non-allergenic, highly antigenic, and global population coverage of 68.03% according to in-silico analysis. However, this can be further tested in in-vitro and in-vivo investigations. Epitopes were sequentially merged to construct a MESV consisting of 393 amino acids using adjuvant and linkers. Molecular docking and simulation studies revealed stable and high-affinity interactions. Furthermore, in-silico immune response graphs showed effective immune response generation. Finally, higher CAI value ensured high gene expression of vaccine in the host cell. ConclusionThe designed MESV construct in the present in-silico study can be effective in generating an immune response against the yellow fever virus. Therefore, to prevent yellow fever, it can be an effective vaccine candidate. However, further downstream, in-vitro study is required.

Plant Resource Use and Pattern of Usage by the Naturalized Orchid Bee (Euglossa dilemma: Hymenoptera: Apidae) in Florida.

The Neotropical orchid bee Euglossa dilemma was found to be naturalized in southern Florida in 2003, and, by 2022, it had colonized the southern half of Florida. Observations of the bee's collection of plant resources, primarily flowers, were made from 2003 through to 2022 to document its plant usage and understand the patterns of its plant usage. The bee utilized 259 plant taxa, 237 species, and 22 horticultural forms, in 156 genera and 56 families in 263 total uses. Of 247 taxa of flowers, 120 were visited primarily for nectar, 46 for both nectar and pollen, 60 for pollen, including 42 buzz-pollinated flowers, 15 for fragrance chemicals for the males, and 5 for resin rewards by females for nesting. Fragrance chemicals were also collected by males from the leaves of 12 plant species. These extensive resource use data allowed the following predictions to be made. (1) The bee's presence in Florida, distant from its native region of Mexico and Central America and the geographical ranges of other orchid bees, would result the usage of many new taxa of plants. True, half, 74/148 (50%), of the genera and one third, 16/51(31%), of the plant families of the plants with flowers used by the bee were not previously recorded as being utilized by Euglossine bees. (2) Like other naturalized bees, it would use relatively more plants from its native range or congeners of these plants. True, 113/148 (76%) of genera with species bearing collected floral rewards are native or congeners with species native to the bee's native range. (3) Given the bee's long tongue, ability to buzz pollen from poricidal anthers, and ability to collect and use specialized rewards, it would disproportionately use plants with protected or highly specialized floral rewards. True, 180/247 (72%) utilized species bear rewards which were protected and unavailable to, or of no interest to, most other flower visitors.

Wood cookstove use is associated with gastric cancer in Central America and mediated by host genetics

Biomass cookstove food preparation is linked to aero-digestive cancers, mediated by ingested and inhaled carcinogens (e.g., heterocyclic amines, and polycyclic aromatic hydrocarbons). We investigated the association between gastric adenocarcinoma, wood cookstove use, H. pylori CagA infection and risk modification by variants in genes that metabolize and affect the internal dose of carcinogens. We conducted a population-based, case–control study (814 incident cases, 1049 controls) in rural Honduras, a high-incidence region with a homogeneous diet and endemic H. pylori infection, primarily with the high-risk CagA genotype. We investigated factors including wood cookstove use, H. pylori CagA serostatus, and 15 variants from 7 metabolizing genes, and the interactions between wood stove use and the genetic variants. Male sex (OR 2.0, 1.6–2.6), age (OR 1.04, 1.03–1.05), wood cookstove use (OR 2.3, 1.6–3.3), and CagA serostatus (OR 3.5, 2.4–5.1) and two SNPs in CYP1B1 (rs1800440 and rs1056836) were independently associated with gastric cancer in multivariate analysis. In the final multivariate model, a highly significant interaction (OR 3.1, 1.2–7.8) was noted between wood cookstove use and the rs1800440 metabolizing genotype, highlighting an important gene-environment interaction. Lifetime wood cookstove use associates with gastric cancer risk in the high-incidence regions of Central America, and the association is dependent on the rs1800440 genotype in CYP1B1. H. pylori CagA infection, wood cookstove use and the rs1800440 genotype, all of which are highly prevalent, informs who is at greatest risk from biomass cookstove use.