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Background. Fresh pasta filata cheese is considered as one of the most important foods in the Venezuelan diet. It is typically produced by small-scale producers using raw milk. The objective of this research was to molecularly characterize the pathogenic potential of Escherichia coli strains isolated from pasta filata cheese manufactured and marketed in Venezuela. Methodology. In the period between January and March of 2019, a total of 36 strains of E. coli were isolated from a variety of pasta filata cheeses including 17 samples of mozzarella, 16 of telita, and 3 of guayanés. These strains were isolated according to the Venezuelan Commission of Industrial Standards (COVENIN) and identified by conventional methods (biochemical and phenotypic tests). Antimicrobial susceptibility was determined using the disk diffusion technique. Phylogenetic grouping and detection of virulence genes were performed by Polymerase Chain Reaction amplification. Diversity and genetic relationships were determined by Rep-PCR. Results: All strains were susceptible to the tested antibiotics. Phylogroup A (n=19) was the most frequent (52.8%), followed by groups D (n=11; 30.6%), and B1 (n=2; 5.6%). The majority of isolates carried at least two virulence genes, one coding for adhesion mechanisms (fimH) and the other for iron uptake (fyuA). Only one strain of phylogroup A presented a profile consisting of four virulence genes (fimH, fyuA, kpsMT II, and papAH). Four strains that could not be classified according to Clermont's scheme carried resistance genes as well. A heterogeneous population structure was observed by Rep-PCR of the strains. Conclusion: Results support the hypothesis that the E. coli strains isolated from the three types of pasta filata cheeses manufactured and marketed in Venezuela have identical characteristics and virulence factors to Extraintestinal Pathogenic E. coli strains observed in animals and humans, posing a potential health risk. Therefore, it is essential to improve hygienic and sanitary controls at all stages of cheese production and to implement measures for epidemiological surveillance of potentially pathogenic bacterial strains present in Venezuelan, artisanal pasta filata cheeses. DOI: 10.18502/jfqhc.11.3.16589

An experimental demonstration for generating harmonics in the optical Vernier effect (OVE) by cascading tapered single-mode fibres (SMF28) is presented. The tapered optical fibres conformed to a pair of in-series Mach-Zehnder fibre interferometers (MZFI), in which one MZFI was a reference while the other was a sensor. The first-order harmonic was achieved by increasing the distance between tapers of the sensor MZFI by a multiple of (i + 1) times the distance between tapers of the reference MZFI plus a mismatch factor. A series of experiments using an individual MZFI and two MZFIs with traditional and harmonic OVE as displacement sensors were performed to compare their sensitivities and magnification factors and demonstrate the improving the sensitivity. The displacement sensor with the first-order harmonic exhibited a maximum sensitivity of −33.3 nm/mm with an M-factor of 8.53 in the mm range.

Anastrepha ludens is a pestiferous tephritid fly species exhibiting extreme polyphagy. It develops optimally in hosts rich in sugar but low nitrogen content. We studied the geographical influence on the composition of A. ludens 's larval and newly emerged adult gut microbiota in altitudinal (0-2,000 masl) and latitudinal (ca. 800 km from 17° to 22°N latitude) transects along the coastline of the state of Veracruz, Mexico. In the 16 collection sites, we only collected Citrus x aurantium fruit (238 samples of A. ludens larvae and adults, plus 73 samples of pulp) to control for host effect, hypothesizing that there exists a conserved core microbiota that would be dominated by nitrogen-fixing bacteria. We found that latitude triggered more significant changes in the gut microbiota than altitude. Northern and southernmost samples differed the most in microbiota composition, with a trade-off between Acetobacteraceae and Rhizobiaceae driving these differences. As hypothesized, the core microbiota in each sampling site, contained the functional group of nitrogen-fixing bacteria. We conclude that A. ludens larvae can acquire multiple diazotrophic symbionts along its wide distribution range where it infests fruit with a high C:N ratio in the pulp., Competing Interests: The authors declare that they have no competing interests., (© 2024 Aluja et al.)

Introduction: Artisanal raw milk cheese can be an important source of bacteria potentially harmful to humans, such as pathogenic Escherichia coli. The objective of this study was to determine the genetic diversity, pathogenicity, and antimicrobial resistance of 45 E. coli strains isolated from artisanal raw milk cheese in Venezuela., Methods: These strains were isolated according to the procedures established by the Venezuelan Commission of Industrial Standards (COVENIN) and identified by conventional methods. Antimicrobial resistance was determined by the disk diffusion method, while phylogenetic grouping and detection of 6 virulence genes (fimH, kpsMT II, papAH, PAI, fyuA and usp) were performed by PCR amplification. Strain typing was performed by Rep-PCR., Results: Of the 45 isolates, 73.3% were susceptible, while 26.7% were resistant to at least one of the tested antibiotics. Phylogenetic grouping revealed a relatively homogeneous distribution. Phylogenetic group A dominated in 82.2% of the strains followed by B1 and D (8.9% each). Three major virulence factors, fimH, fyuA, and kpsMTII, were genetically encoded in most strains. Rep-PCR typing of E. coli strains revealed a heterogeneous population structure., Conclusions: E. coli isolated from artisanal dairy products share characteristics and virulence genes with extraintestinal pathogenic E. coli (ExPEC) strains from animals and humans, which represents a public health risk. Thus, it is necessary to increase hygienic and sanitary controls, especially those involved in the production stages, and emphasize the epidemiological surveillance of potentially pathogenic bacterial strains present in unpasteurized artisanal cheese marketed in the city of Mérida, Venezuela., Competing Interests: No Conflict of Interest is declared, (Copyright (c) 2024 Leidys Guillén, María Araque.)

Anastrepha ludens (Mexican fruit-fly) is a highly polyphagous fruit fly species (Tephritidae) attacking wild and commercial fruit from Mexico to Panama. Here we report on a recent habitat and host range expansion as A. ludens lately started to attack apples (Malus domestica) in Mexico, a phenomenon likely influenced by global warming. We document natural infestations in apple-growing regions in the States of Nuevo León and Hidalgo, Mexico where A. ludens has started to attack the cultivars 'Golden Delicious', 'Rayada' and 'Criolla'. No infestations were found in the apple-growing region of Zacatlán, Puebla. To determine apple cultivar susceptibility to the attack of this emerging pest, we ran forced infestation assays in enclosed fruit-bearing branches in all three apple-growing regions and studied the metabolome of all fruit. A clear pattern emerged indicating that the cultivar 'Golden Delicious' was the most susceptible, with 'Criolla' exhibiting complete resistance in one location (Puebla). Although A. ludens can develop in this new host, development rates (egg-adult) and adult emergence were affected when compared with the performance in the natural host 'Marsh' grapefruit. Warmer temperatures and specific secondary metabolites of some apple cultivars are likely contributing to the territorial and host expansion of A. ludens., Competing Interests: Competing interests The authors declare no competing interests. Ethics declarations The authors declare that only insects were used and that special care was taken to only use the necessary amount. Grower approval for apple collections We worked in commercial apple orchards with a commercially significant pest. We obtained verbal permissions from all orchard owners under a gentleman´s agreements as that is the local custom. Growers or their administrators supervised our work in all cases. No official permissions were needed also in the case of the fruit fly pest., (© 2024. The Author(s).)

Background: In the Americas, deaths by diseases avoidable with vaccines are a significant contributor to child mortality. An essential means of reducing this is through broad vaccine coverage. The COVID-19 pandemic has posed a potential disruption to vaccine coverage due to its effects on the healthcare system., Objectives: this study aims to evaluate the impact of the COVID-19 pandemic on DTP3 vaccination coverage in the Americas, investigating trends from 2012 to 2022 to identify significant changes, regional disparities, and the overall effect of the pandemic on progress towards global immunization targets., Methods: This study used the coverage data for the third dose of the diphtheria, tetanus, and pertussis vaccine (DTP3) pulled from UNICEF databases spanning 2012 to 2022. We conducted a Joinpoint regression to identify points of significant trend changes. The annual percentage change (APC) and 95% confidence intervals (95% CIs) were calculated for America and its regions. We also used segmented regression analysis. Using the Chi-square test, we compared DTP3 vaccination coverage for each country between 2019 and 2022., Results: Overall, America saw a decrease in vaccine coverage during this period, with an APC of -1.4 (95% CI -1.8; -1.0). This trend varied across regions. In North America, the decrease was negligible (-0.1% APC). South America showed the steepest decrease, with an APC of -2.5%. Central America also declined, with an APC of -1.3%. Our findings suggest a concerning trend of declining DTP-vaccination rates in the Americas, exacerbated in certain regions, in the wake of the COVID-19 pandemic. The absolute decrease in vaccine coverage in the Americas was -4% between 2019 and 2022, with the most important drop being in Central America (-7%). However, six countries reported increased vaccination rates post-COVID-19, led by Brazil, with a 7% increase. Conversely, twenty-two countries registered a decline in DTP3 vaccine coverage, with the average decrease being -7.37%. This decline poses an important challenge to achieving the WHO's target of 90% coverage for the third dose of DTP by 2030, as evidenced by the reduction in the number of countries meeting this target from 2019 to 2022., Conclusions: The COVID-19 pandemic has impacted vaccine coverage in America, leading to a decrease, especially across Central America.

Research on larval rearing and nutrition of tephritid flies on artificial diets is key for the sterile insect technique. Here, we examined the effects of the type of gel (calcium alginate, agar, or carrageenan), at varying percentages in artificial diets for the polyphagous pest Anastrepha ludens , on the physicochemical and nutritional traits of the diets, and the effects of the type of gel, the gel content and the larval density (larvae/g of diet) used in production, quality parameters for mass-reared tephritids, diet removal (an indirect estimation of diet consumption), and nutritional traits of flies. Regardless of the gel content, calcium alginate diets were firmer and more resistant to penetration than the agar and carrageenan diets. The larval recovery, pupation, pupal weight, and flight ability of A. ludens were lower in calcium alginate diets than in agar and carrageenan diets. Diet removal was higher in calcium alginate diets; however, low levels of ammonium and high levels of uric acid in excretions from larvae on these diets suggest an alteration in protein metabolism. The firmness and penetration resistance characteristics of calcium alginate diets may have limited movement and feeding of larvae, but this could be overcome by the collective feeding of large groups of larvae. Our findings provide insights into the mechanism governing gel-diet rearing systems for A. ludens .

Using light, transmission, scanning electron, and confocal microscopy, we carried out a morphological study of antennal sensilla and their ultrastructures of the Mexican Fruit Fly Anastrepha ludens (Loew), an economically important species that is a pest of mangos and citrus in Mexico and Central America. Our goal was to update the known information on the various sensilla in the antennae of A. ludens , involved in the perception of odors, temperature, humidity, and movement. Based on their external shape, size, cuticle-thickness, and presence of pores, we identified six types of sensilla with 16 subtypes (one chaetica in the pedicel, four clavate, two trichoid, four basiconic, one styloconic, and one campaniform-like in the flagellum, and three additional ones in the two chambers of the sensory pit (pit-basiconic I and II, and pit-styloconic)), some of them described for the first time in A. ludens . We also report, for the first time, two types of pores in the sensilla (hourglass and wedge shapes) that helped classify the sensilla. Additionally, we report a campaniform-like sensillum only observed by transmission electronic microscopy on the flagellum, styloconic and basiconic variants inside the sensory pit, and an "hourglass-shaped" pore in six sensilla types. We discuss and suggest the possible function of each sensillum according to their characteristics and unify previously used criteria in the only previous study on the topic.

Under uncertainty, leaders who possess dark triad personality traits seem able to attain leadership positions. We draw on uncertainty-identity theory and dark triad research to explore the effect of self-uncertainty on leadership motivation. Uncertainty-identity theory predicts that people can reduce self-uncertainty by identifying with groups and following their leaders, which suggests that self-uncertainty reduces people's own leadership motivation. However, individuals high in dark triad traits (Machiavellianism, narcissism, and psychopathy) have such a powerful drive for dominance over others that their leadership motivation may be unaffected by self-uncertainty. To test these predictions, we conducted four studies ( N s = 2,641, 421, 513, and 400). We found that self-uncertainty reduced leadership motivation for individuals low in the dark triad. In contrast, those high in the dark triad had an elevated leadership motivation that remained unaltered when they were self-uncertain. These effects were mediated by participants' negative affect. We discuss the implications of these findings.

Anastrepha ludens is a polyphagous frugivorous tephritid that infests citrus and mango. Here, we report the establishment of a laboratory colony of A. ludens reared on a larval medium that is a waste for the citrus industry, specifically, orange ( Citrus × sinensis ) fruit bagasse. After 24 generations of rearing on a nutritionally poor orange bagasse diet, pupae weighed 41.1% less than pupae from a colony reared on a nutritionally rich artificial diet. Larvae from the orange bagasse diet had 6.94% less protein content than larvae from the artificial diet, although their pupation rate was similar. Males from the orange bagasse diet produced a scent bouquet with 21 chemical compounds and were sexually competitive, but they had significantly shorter copulations when compared to males from the artificial diet and from the wild host, Casimiroa edulis , which had relatively simple scent bouquets. The chemical complexity in the odors of males from the orange bagasse diet might initially have attracted females to novel scent combinations, but, once in the copula, they may have been able to sense negative characteristics in males, leading them to terminate copulations soon after they began. We conclude that A. ludens can adjust morphological, life history, nutritional, and chemical traits when adapted to a larval environment consisting of fruit bagasse.

Climate change, particularly global warming, is disturbing biological processes in unexpected ways and forcing us to re-study/reanalyze the effects of varying temperatures, among them extreme ones, on insect functional traits such as lifespan and fecundity/fertility. Here we experimentally tested, under both laboratory and field conditions, the effects of an extreme range of temperatures (5, 10, 15, 20, 30, 40, and 45 °C, and the naturally varying conditions experienced in the field), on survivorship/lifespan, fecundity, and fertility of four pestiferous fruit fly species exhibiting contrasting life histories and belonging to two phylogenetic groups within the genus Anastrepha : A. ludens, A. obliqua, A. striata , and A. serpentina . In the field, we also measured the length of the entire life cycle (egg to adult), and in one species ( A. ludens ), the effect on the latter of the host plant (mango and grapefruit). Under laboratory conditions, none of the adults, independent of species, could survive a single day when exposed to a constant temperature of 45 °C, but A. striata and A. serpentina females/males survived at the highly contrasting temperatures of 5 and 40 °C at least 7 days. Maximum longevity was achieved in all species at 15 °C (375, 225, 175 and 160 days in A. ludens, A. serpentina, A. striata and A. obliqua females, respectively). Anastrepha ludens layed many eggs until late in life (368 days) at 15 °C, but none eclosed. Eclosion was only observed in all species at 20 and 30 °C. Under natural conditions, flies lived ca. 100 days less than in the laboratory at 15 °C, likely due to the physiological cost of dealing with the highly varying environmental patterns over 24 h (minimum and maximum temperatures and relative humidity of ca. 10-40 °C, and 22-100%, respectively). In the case of A. ludens , the immature's developmental time was shorter in mango, but adult survival was longer than in grapefruit. We discuss our results considering the physiological processes regulating the traits measured and tie them to the increasing problem of global warming and its hidden effects on the physiology of insects, as well as the ecological and pest management implications., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Guillén, Pascacio-Villafán, Osorio-Paz, Ortega-Casas, Enciso-Ortíz, Altúzar-Molina, Velázquez and Aluja.)

Chemical ecology studies on ambrosia beetles are typically conducted with either wild or laboratory-reared specimens. Unlike laboratory-reared insects, important aspects that potentially influence behavioral responses, such as age, physiological state, and prior experience are unknown in wild specimens. In this study, we compared the electroantennographic (EAG) responses of laboratory-reared and wild X. affinis and X. ferrugineus to 70% ethanol and bark odors (host kairomones) of Bursera simaruba , Mangifera indica , and Persea schiedeana aged for 2, 24, and 48 h. Chemical analyses of each odor treatment (bark species x length of aging) were performed to determine their volatilome composition. EAG responses were different between laboratory-reared and wild X. ferrugineus when exposed to ethanol, whereas wild X. affinis exhibited similar EAG responses to the laboratory-reared insects. Ethanol elicited the strongest olfactory responses in both species. Among the bark-odors, the highest responses were triggered by B. simaruba at 48 h in X. affinis , and P. schiedeana at 24 and 48 h in X. ferrugineus . Volatile profiles varied among aged bark samples; 3-carene and limonene were predominant in B. simaruba , whereas α-copaene and α-cubebene were abundant in P. schiedeana. Further studies are needed to determine the biological function of B. simaruba and P. schiedeana terpenes on X. affinis and X. ferrugineus, and their potential application for the development of effective lures.

Objectives: To analyze the frequencies of 3 types of hospital revisits by patients after treatment for COVID-19 in the emergency department., Material and Methods: Retrospective observational study of consecutive patients who came to the emergency department in March and April 2020 and were discharged alive with a diagnosis of COVID-19. Baseline and acute episode data were collected and the patients were followed for 1 year. We analyzed variables associated with revisits for any reason, revisits related to COVID-19, and early COVID-19-related revisits (within 30 days)., Results: A total of 1352 patients with a mean age of 62.1 years (52.9% male) were studied. A total of 553 revisits were made by 342 patients (25.3%) for any reason; 132 (9.8%) revisited in relation to COVID-19 at least once. Of those, 103 (7.6%) revisited within 30 days (early) and 29 (2.2%) came later. COVID-19-related revisits were associated with thrombotic events (odds ratio [OR], 7.58; 95% CI, 1.75-32.81) and pulmonary fibrosis (OR, 4.95; 95% CI, 1.27-19.24); early revisits were inversely associated with follow-up management by a contracted health care support service (OR, 0.18; 95% CI, 0.03-0.92). Hospital admission during the initial visit was significantly associated with fewer revisits for any reason or related to COVID-19 at any time., Conclusion: Fewer than half the total number of emergency department revisits after initial care for COVID-19 were related to the novel coronavirus infection. Revisits occurred more often in the first 30 days after discharge. Later COVID-19-related revisits were uncommon, but given the large number of patients with this infection, such visits can be expected.

With the aim of identifying key factors that determine oviposition decisions by Anastrepha obliqua for management purposes, we conducted a behavioral study under natural/semi-natural field conditions to identify where exactly in the fruit (upper, middle, or lower sections) females preferred to lay eggs in a highly susceptible mango cultivar ("Criollo"), and whether sunlight incidence and fruit chemical compounds influenced oviposition site selection by this pestiferous fly. Females oviposited in shaded, upper fruit sections where pulp had higher total carbohydrate concentrations but similar total protein, lipid, and polyphenol concentrations than non-oviposited sections. Peel had higher overall nutrient and mangiferin/quercetin-3-D-galactoside (polyphenols) concentrations. An untargeted metabolomic analysis of oviposited and non-oviposited fruit sections identified abscisic acid (ABA) and dihydrophaseic acid glucoside, a by-product of ABA catabolism, as potential chemical markers that could play a role in fruit acceptance behaviors by female flies. We conclude that females preferentially oviposit in fruit sections with optimal chemical and environmental conditions for larval development: more carbohydrates and antioxidants such as mangiferin and ferulic acid and lesser sunlight exposure to avoid lethal egg/larval desiccation/overheating. We make specific recommendations for A . obliqua management based on female host selection behavior, a tree pruning scheme exposing fruit to direct sunlight, application of a host marking pheromone, and the use of egg sinks in the orchard.