Implications of migratory and exotic birds and the mosquito community on West Nile virus transmission.

BACKGROUND: Vector-borne diseases like West Nile virus (WNV) pose a global health challenge, with rising incidence and distribution. Culex mosquitoes are crucial WNV vectors. Avian species composition and bird community diversity, along with vector communities, influence WNV transmission patterns. However, limited knowledge exists on their impact in southwestern Spain, an area with active WNV circulation in wild birds, mosquitoes, and humans. METHODS: To address this, we conducted a comprehensive study investigating the contributions of migratory and exotic bird species to WNV transmission and the influence of mosquito community composition. RESULTS: Analysing 1194 serum samples from 44 avian species, we detected WNV antibodies in 32 samples from 11 species, four for the first time in Europe. Migratory birds had higher WNV exposure likelihood than native and exotic species, and higher phylogenetic diversity in bird communities correlated with lower exposure rates. Moreover, in 5859 female mosquitoes belonging to 12 species, we identified WNV competent vectors like Cx. pipiens s.l. and the Univittatus subgroup. Birds with WNV antibodies were positively associated with competent vector abundance, but negatively with overall mosquito species richness. CONCLUSIONS: These findings highlight the complex interactions between bird species, their phylogenetics, and mosquito vectors in WNV transmission. Understanding these dynamics will help to implement effective disease control strategies in southwestern Spain.

Changes in Morphology, Metabolism and Composition of Cuticular Wax in Zucchini Fruit During Postharvest Cold Storage.

Cuticle composition is an important economic trait in agriculture, as it is the first protective barrier of the plant against environmental conditions. The main goal of this work was to study the role of the cuticular wax in maintaining the postharvest quality of zucchini fruit, by comparing two commercial varieties with contrasting behavior against low temperatures; the cold-tolerant variety 'Natura', and the cold-sensitive 'Sinatra', as well as 'Sinatra' fruit with induced-chilling tolerance through a preconditioning treatment (15°C for 48 h). The freshly-harvested 'Natura' fruit had a well-detectable cuticle with a significant lower permeability and a subset of 15 up-regulated cuticle-related genes. SEM showed that zucchini epicuticular waxes mainly consisted of round-shaped crystals and clusters of them, and areas with more dense crystal deposition were found in fruit of 'Natura' and of preconditioned 'Sinatra'. The cuticular wax load per surface was higher in 'Natura' than in 'Sinatra' fruit at harvest and after 14 days at 4°C. In addition, total cuticular wax load only increased in 'Natura' and preconditioned 'Sinatra' fruit with cold storage. With respect to the chemical composition of the waxes, the most abundant components were alkanes, in both 'Natura' and 'Sinatra', with similar values at harvest. The total alkane content only increased in 'Natura' fruit and in the preconditioned 'Sinatra' fruit after cold storage, whereas the amount of total acids decreased, with the lowest values observed in the fruit that showed less chilling injury (CI) and weight loss. Two esters were detected, and their content also decreased with the storage in both varieties, with a greater reduction observed in the cold-tolerant variety in response to low temperature. Gene expression analysis showed significant differences between varieties, especially in CpCER1-like and CpCER3-like genes, involved in alkane production, as well as in the transcription factors CpWIN1-like and CpFUL1-like, associated with cuticle development and epidermal wax accumulation in other species. These results suggest an important role of the alkane biosynthetic pathway and cuticle morphology in maintaining the postharvest quality of zucchini fruit during the storage at low temperatures.

West Nile and Usutu virus infections in wild birds admitted to rehabilitation centres in Extremadura, western Spain, 2017-2019.

West Nile virus (WNV) is an emerging flavivirus transmitted generally by mosquitoes of Culex genus. It is maintained in an enzootic life cycle where birds act as reservoir hosts. Humans and horses are also susceptible to infection, and occasionally, they suffer from neurological complications. However, they do not transmit the virus to other vectors, behaving as dead-end hosts. Sporadic WNV outbreaks observed in horses and wild birds from Extremadura (western Spain) during 2016 and 2017 seasons prompted to carry out this survey in wild birds, focused on specimens coming from two wildlife rehabilitation centres. Between October 2017 and December 2019, samples from 391 wild birds, belonging to 56 different species were collected and analysed in search of evidence of WNV infection. The analysis of serum samples for WNV-specific antibodies by ELISA, whose specificity was subsequently confirmed by virus-neutralisation test (VNT) showed positive results in 18.23 % birds belonging to 18 different species. Pelecaniformes (33.33 %), Accipitriformes (25.77 %) and Strigiformes (22.92 %) orders had the higher seroprevalences. Remarkably, WNV-specific antibodies were found in a black stork for the first time in Europe. Analysis by real time RT-PCR in symptomatic birds confirmed the presence of WNV lineage 1 RNA in griffon vulture and little owls. Specificity analysis of ELISA positive and doubtful sera was performed by differential VNT titration against WNV and two other cross-reacting avian flaviviruses found in Spain: Usutu virus (USUV) and Bagaza virus (BAGV). Only four samples showed USUV-specific antibodies (1.04 %) corresponding to three species: Eurasian eagle-owl, griffon vulture and great bustard (first detection in Europe) whereas no samples were found reactive to BAGV. Differential VNT yielded undetermined flavivirus result in 16 samples (4.17 %). This is the first study carried out on wild birds from Extremadura (western Spain). It highlights the widespread circulation of WNV in the region and its co-circulation with USUV.

Serological evidence of co-circulation of West Nile and Usutu viruses in equids from western Spain.

West Nile virus (WNV) is a mosquito-borne emerging virus in Europe with capacity to cause neurological complications such as encephalitis or meningoencephalitis in humans, birds or equids. In Spain, WNV is actively circulating in mosquitoes, birds and horses in different regions, but never has been deeply studied in Extremadura. Therefore, the aim of this study was to evaluate the seroprevalence of WNV in equids of those areas and to analyse the risk factors associated with exposure to the virus. A total of 199 out of 725 equids presented antibodies against WNV by competition ELISA (27.45%), while 22 were doubtful (3.03%). Anti-WNV IgM antibodies were detected in 16 equids (2.21%), and 3 animals were doubtful (0.41%). All ELISA-reactive positive/doubtful sera (N = 226) were further tested by micro-virus neutralization test (VNT), and a total of 143 horses were confirmed as positive for WNV, obtaining a seroprevalence of 19.72% in equids of western Spain. In addition, specific antibodies against USUV were confirmed in 11 equids. In 24 equids, a specific flavivirus species (detected by ELISA test) could not be determined. The generalized linear mixed-effects models showed that the significant risk factors associated with individual WNV infection in equids were the age (adults) and hair coat colour (light), whereas in USUV infections, it was the breed (pure). Data demonstrated that WNV and USUV are circulating in regions of western Spain. Given the high WNV seroprevalence found in equids from the studied areas, it is important to improve the surveillance programmes of public health to detect undiagnosed human cases and to establish a vaccination programme in equid herds in these regions.

Exogenous γ-aminobutyric acid treatment improves the cold tolerance of zucchini fruit during postharvest storage.

This work examines the effect of a treatment with 1 mM of γ-aminobutyric acid (GABA) on zucchini fruit during postharvest cold storage. Specifically, the effect of GABA on postharvest quality was measured, as well as its implication in the GABA shunt and other related metabolic pathways. The treatments were performed in Sinatra, a variety of zucchini highly sensitive to low-temperature storage. The application of GABA improved the quality of zucchini fruit stored at 4 °C, with a reduction of chilling-injury index, weight loss, and cell death, as well as a lower rate of electrolyte leakage. GABA content was significantly higher in the treated fruit than in the control fruit at all times analyzed. At the end of the storage period, GABA-treated fruit had higher contents of both proline and putrescine. The catabolism of this polyamine was not affected by exogenous GABA. Also, over the long term, the treatment induced the GABA shunt by increasing the activities of the enzymes GABA transaminase (GABA-T) and glutamate decarboxylase (GAD). GABA-treated fruit contained higher levels of fumarate and malate than did non-treated fruit, as well as higher ATP and NADH contents. These results imply that the GABA shunt is involved in providing metabolites to produce energy, reduce power, and help the fruit to cope with cold stress over the long term.

Quality of life in persons with Human Immunodeficiency Virus infection in Mexico / Calidad de vida en personas infectadas con virus de la inmunodeficiencia humana en México

Background: The evaluation of quality of life related to health (HRQOL) has become an important prognostic indicator in HIV/AIDS. The aim of this study was to determine the impact of socio-demographic, clinical and psychological factors in HRQOL in a group of subjects with HIV/AIDS in northwestern Mexico and determine which variables best predict HRQOL. Methods: In a cross-sectional study with a sample of 87% of patients receiving care at a clinic for HIV/AIDS in northwestern Mexico between November 2010 to June 2011, we measure the HRQOL using the Tool Medical Outcomes Study HIV Health Survey (MOS-HIV). A model of multiple linear regression was performed to identify variables that allow us to predict HRQOL in this population. Results: In a sample of 54 subjects with HIV/AIDS. Patients had an average age of 43 ± 9 years, 83% were men with a mean time of 6.5 ± 4.5 years from diagnosis. HRQOL scores of physical and mental health of the participants were 57 ± 6 and 57 ± 13 respectively. In multivariate analysis, the variables that influenced the physical health punctuation were gender, marital status, sexual orientation, time since diagnosis and viral load (log). Conclusions: Prospective studies are needed to better explain the influence of the factors that predict changes or trends in HRQOL in patients with HIV/AIDS.

Introducción: la evaluación de la calidad de vida relacionada con la salud (CVRS) se ha convertido en un importante indicador pronóstico en el enfermo con VIH/SIDA. El objetivo de este estudio fue determinar el impacto de los factores sociodemográficos, clínicos y psicológicos en la CVRS de un grupo de pacientes portadores de VIH/SIDA del noroeste de México, así como determinar qué variables predicen mejor la CVRS. Métodos: estudio transversal con una muestra del 87% de los pacientes que recibían atención en una clínica de VIH/SIDA en el noroeste de México, entre noviembre del 2010 y junio del 2011, se midió la CVRS utilizando el instrumento Medical Outcomes Study HIV Health Survey (MOS-HIV). Se realizó un modelo de regresión lineal múltiple para identificar aquellas variables que permiten predecir la CVRS en esta población. Resultados: en una muestra de 54 sujetos con VIH/SIDA que tenían una edad de 43 ± 9 años, 83% eran hombres con un tiempo de 6.5 ± 4.5 años desde el diagnóstico. Las puntuaciones de CVRS de salud mental y física de los participantes fueron de 57 ± 6 y 57 ± 13 respectivamente. En el análisis multivariado, las variables que influyeron en la puntuación de salud física fueron el género, el estado civil, la orientación sexual, el tiempo transcurrido desde el diagnóstico y la carga viral (log). Conclusiones: es necesario realizar estudios prospectivos para explicar mejor la influencia de los factores que predicen cambios o tendencias en la CVRS en pacientes con VIH/SIDA.

Oxidative Stress Associated with Chilling Injury in Immature Fruit: Postharvest Technological and Biotechnological Solutions.

Immature, vegetable-like fruits are produced by crops of great economic importance, including cucumbers, zucchini, eggplants and bell peppers, among others. Because of their high respiration rates, associated with high rates of dehydration and metabolism, and their susceptibility to chilling injury (CI), vegetable fruits are highly perishable commodities, requiring particular storage conditions to avoid postharvest losses. This review focuses on the oxidative stress that affects the postharvest quality of vegetable fruits under chilling storage. We define the physiological and biochemical factors that are associated with the oxidative stress and the development of CI symptoms in these commodities, and discuss the different physical, chemical and biotechnological approaches that have been proposed to reduce oxidative stress while enhancing the chilling tolerance of vegetable fruits.

Contribution of polyamines and other related metabolites to the maintenance of zucchini fruit quality during cold storage.

In order to investigate the contribution of polyamines and related amino acids in the maintenance of zucchini fruit quality during cold storage, two varieties of Cucurbita pepo with different degrees of chilling tolerance were used, Natura (more tolerant) and Sinatra (moresensitive). After harvest, free putrescine levels decreased during storage at 20 °C, whereas in fruit kept at 4 °C this polyamine accumulated in both varieties, but with higher levels in the sensitive variety (Sinatra). This behavior suggests that putrescine is accumulated as a response to low temperature in zucchini fruit by stress-induced chilling injury, and not due to the postharvest storage itself. ADC activity responds quickly to chilling but sharply decreases after 14 days, whereas its expression remains high in both varieties. ODC activity takes over when the cold stress is relatively severe, as this activity was found to be much higher in Sinatra. ODCexpression also correlated with ODC activity. DAO activity increased in Natura fruit, and conversely decreased in Sinatra fruit during storage at 4 °C, whereas the proline content was higher in Natura and lower in Sinatra. Therefore, we suggest that putrescine degradation and proline accumulation contribute to the acquisition of chilling tolerance in zucchini fruit. GABA content decreased in both varieties, with a greater reduction in Natura fruit and less in Sinatra fruit. In addition, GABA transaminase showed a higher activity in Natura fruit than in Sinatra fruit during cold storage, suggesting that GABA catabolism could be involved in the tolerance to postharvest cold storage in zucchini fruit.

Changes in carbohydrate content in zucchini fruit (Cucurbita pepo L.) under low temperature stress.

The postharvest handling of zucchini fruit includes low-temperature storage, making cold stress unavoidable. We have investigated the changes of soluble carbohydrates under this stress and its relation with weight loss and chilling injury in zucchini fruit during postharvest storage at 4 °C and 20 °C for up to 14 days. Two varieties with different degrees of chilling tolerance were compared: Natura, the more tolerant variety, and Sinatra, the variety that suffered more severe chilling-injury symptoms and weight loss. In both varieties, total soluble carbohydrates, reducing soluble carbohydrates and polyols content was generally higher during storage at 4 °C than at 20 °C, thus these parameters are related to the physiological response of zucchini fruit to cold stress. However, the raffinose content increased in Natura and Sinatra fruits during storage at 4 °C and 20 °C, although at 20 °C the increase in raffinose was more remarkable than at 4 °C in both varieties, so that the role of raffinose could be more likely related to dehydration than to chilling susceptibility of zucchini fruit. Glucose, fructose, pinitol, and acid invertase activity registered opposite trends in both varieties against chilling, increasing in Natura and decreasing in Sinatra. The increase in acid invertase activity in Natura fruit during cold storage could contribute in part to the increase of these reducing sugars, whose metabolism could be involved in the adaptation to postharvest cold storage.

Knowledge and attitudes of low back pain in physicians based in clinical practice guidelines / Conhecimento e conduta em casos de lombalgia com base nas diretivas de prática clínica / Conocimientos y actitudes sobre lumbalgia de médicos basados en la guía práctica clínica

Objective: To determine the level of knowledge and attitudes of physicians in Tijuana based on Clinical Practice Guidelines (CPG) for the prevention, diagnosis and treatment of Nonspecific Low Back Pain (NLBP). Methods: Prospective, cross-sectional, descriptive study. Data were obtained from doctors who practice in clinics, private surgeries, and/or government institutions. Results: Of a total of 56 doctors surveyed, 37 were men and 19 women. None of the doctors said they had not seen a patient with Back Pain. 49% knew the GPC, and 51% did not know of its existence. Conclusions: Although some physicians reported knowledge of the GPC, according to the results, there was a lack of full knowledge of, and adherence to these guidelines. Not knowing the GPC did not make it impossible to complete the questionnaire. The doctors felt more connected to the health system, but with less confidence in the management of cases of NLBP.

Objetivo: Determinar o nível de conhecimentos e a conduta dos médicos de Tijuana, com base nas Diretivas de Prática Clínica (DPC) para prevenção, diagnóstico e tratamento da dor lombar não específica (DLNE). Métodos: Estudo prospectivo, transversal e descritivo. Os dados foram obtidos junto a médicos que prestam serviços em clínicas, consultórios particulares e/ou instituições governamentais. Resultados: Atingiu-se um total de 56 médicos entrevistados, dos quais 37 eram homens e 19 mulheres. Nenhum médico disse que não atende um paciente com dor lombar. Do total, 49% conhecem as DPC e 51% não sabiam da sua existência. Conclusões: Apesar de alguns médicos relatarem conhecer as DPC, de acordo com os resultados obtidos, falta-lhes maior domínio e conformidade com relação a essas diretivas. Não conhecer as DPC não impossibilita responder ao questionário. Os médicos sentem-se mais conectados ao sistema de saúde, mas com menos confiança na conduta em casos DLI.

Objetivo: Determinar el nivel de conocimientos y las actitudes de los médicos en Tijuana, con base en la Guía de Práctica Clínica (GPC) para la prevención, diagnóstico y tratamiento del Dolor Lumbar Inespecífico (DLI). Métodos: Estudio prospectivo, transversal y descriptivo. Los datos fueron obtenidos de los médicos que prestan sus servicios en clínicas, consultorios privados y/o instituciones de gobierno. Resultados: Se obtuvo un total de 56 médicos encuestados, 37 hombres y 19 mujeres. Ningún médico contestó que no atiende un paciente con dolor lumbar. El 49% conocen la GPC y el 51% no saben de su existencia. Conclusiones: A pesar de que algunos médicos refieren conocer la GPC, según los resultados obtenidos falta mayor dominio y apego de la misma. El no conocer la GPC no hace imposible contestar el cuestionario. Los médicos se sienten más conectados con el sistema de salud, pero con menor autoconfianza en el manejo del DLI.