Transcriptional response of laboratory-reared Mexican fruit flies (Anastrepha ludens Loew) to desiccation.

Confronting environments with low relative humidity is one of the main challenges faced by insects with expanding distribution ranges. Anastrepha ludens (the Mexican fruit fly) has evolved to cope with the variable conditions encountered during its lifetime, which allows it to colonise a wide range of environments. However, our understanding of the mechanisms underpinning the ability of this species to confront environments with low relative humidity is incomplete. In this sense, omic approaches such as transcriptomics can be helpful for advancing our knowledge on how this species copes with desiccation stress. Considering this, in this study, we performed transcriptomic analyses to compare the molecular responses of laboratory-reared A. ludens exposed and unexposed to desiccation. Data from the transcriptome analyses indicated that the responses to desiccation are shared by both sexes. We identified the up-regulation of transcripts encoding proteins involved in lipid metabolism and membrane remodelling, as well as proteases and cuticular proteins. Our results provide a framework for understanding the response to desiccation stress in one of the most invasive fruit fly species in the world.

Accelerating sexual maturation of male Anastrepha ludens (Diptera: Tephritidae) fruit flies by adding two juvenile hormone analogues.

BACKGROUND: Improving the mating competitiveness and survival of sterile males are direct means to increase the effectiveness of the sterile insect technique (SIT). Some insecticide growth regulators, such as the juvenile hormone analogue (JHA) methoprene, have been used to improve the mating competitiveness of male tephritid flies by reducing their sexual maturation period. However, the application of methoprene reduces fly resistance to stress and decreases survival. Here, we compared the effects of methoprene and pyriproxyfen (PPF), another JHA, in Anastrepha ludens males. PPF is an insect growth regulator that exhibits higher negative effects on the larval molting process than methoprene or natural juvenile hormone. Both compounds were administered at two doses (0.05% and 0.10%) via the male diet immediately after emergence. RESULTS: Our results show that both PPF and methoprene reduced male sexual maturation. However, PPF-treated males exhibited a shorter maturation period and obtained more matings at a given age than methoprene-treated males. No significant differences were observed between the two PPF doses tested (0.05% and 0.10%). Male survival was equally reduced by the two compounds. CONCLUSION: Our results demonstrate that PPF accelerated sexual development without reducing the mating propensity of sterile male flies and can be used as a suitable alternative for methoprene. © 2023 Society of Chemical Industry.

Calidad del sueño y sus alteraciones durante la Pandemia por COVID-19 en una región del norte de Chile

Introducción: Las alteraciones del sueño son prevalentes en la población. La pandemia por SARSCoV-2 y la implementación de medidas de confinamiento para combatir su propagación podrían favorecer el desarrollo de trastornos del sueño o empeorar los preexistentes. Objetivo: Evaluar la calidad de sueño y somnolencia diurna durante la pandemia en la región de Coquimbo, Chile mediante la aplicación de encuesta validada. Metodología: Estudio observacional, descriptivo y transversal de carácter analítico. Tamaño muestral de 1.074 participantes. Intervalo de confianza 95%, margen de error 3%. Recopilación a través de un cuestionario online que incluye el Índice de Pittsburgh (PSQI), y Escala de Epworth (ESEp), ambos autoaplicables y validados al español. Análisis con programa SPSS-26. Aprobado por Comité de Ética. Resultados: 80,1% presentó alteraciones en calidad de sueño (PSQI), y 50,2% tuvo algún grado de somnolencia diurna según ESEp. Las mujeres presentaron peor calidad de sueño y mayor somnolencia diurna que los hombres con una diferencia estadísticamente significativa. Discusión/conclusión: El sueño es una función de gran relevancia para los seres vivos y sus alteraciones pueden ocasionar consecuencias importantes para la salud, lo cual preocupa en un sistema sanitario ya sobrecargado, más aún en pandemia, por lo que resulta importante incentivar la toma de medidas como una buena higiene del sueño para mejorar la calidad de vida de la población.

Background: Sleep disorders are prevalent in the general population. The SARS-CoV-2 pandemic and the implementation of sanitary measures to combat its spread, could worst sleep disorders or worsen preexisting ones. Objective: Evaluate the quality of sleep and daytime sleepiness during the pandemic in the Coquimbo region, Chile through the application of a validated sleep survey. Methodology: Observational, descriptive and cross-sectional study. Sample size of 1,074 participants. Confidence interval 95%, error range 3%. The survey was performed through an online questionnaire, that includes the Pittsburgh Index (PSQI) and the Epworth Scale (ESEp), both self-applied and validated in Spanish. Analysis with SPSS-26 program. Approved by the Ethics Committee. Results: 80.1% presented alterations in sleep quality (PSQI), and 50.2% had daytime sleepiness according to ESSep. The women presented worse quality of sleep and more daytime sleepiness than the men, with a statistically significant difference. Discussion/conclusion: Sleep is a important function for humans and other beings, and its alterations can cause important consequences for health. It is an important factor for the already overloaded health system, even more so in a pandemic. It is important to taking of measures such as good sleep hygiene to improve the quality of life of the population.

Aquiluscidin, a Cathelicidin from Crotalus aquilus, and the Vcn-23 Derivative Peptide, Have Anti-Microbial Activity against Gram-Negative and Gram-Positive Bacteria.

Anti-microbial peptides play a vital role in the defense mechanisms of various organisms performing functions that range from the elimination of microorganisms, through diverse mechanisms, to the modulation of the immune response, providing protection to the host. Among these peptides, cathelicidins, a well-studied family of anti-microbial peptides, are found in various animal species, including reptiles. Due to the rise in anti-microbial resistance, these compounds have been suggested as potential candidates for developing new drugs. In this study, we identified and characterized a cathelicidin-like peptide called Aquiluscidin (Aq-CATH) from transcripts obtained from the skin and oral mucosa of the Querétaro's dark rattlesnake, Crotalus aquilus. The cDNA was cloned, sequenced, and yielded a 566-base-pair sequence. Using bioinformatics, we predicted that the peptide precursor contains a signal peptide, a 101-amino-acid conserved cathelin domain, an anionic region, and a 34-amino-acid mature peptide in the C-terminal region. Aq-CATH and a derived 23-amino-acid peptide (Vcn-23) were synthesized, and their anti-microbial activity was evaluated against various species of bacteria in in vitro assays. The minimal inhibitory concentrations against bacteria ranged from 2 to 8 µg/mL for both peptides. Furthermore, at concentrations of up to 50 µM, they exhibited no significant hemolytic activity (<2.3% and <1.2% for Aquiluscidin and Vcn-23, respectively) against rat erythrocytes and displayed no significant cytotoxic activity at low concentrations (>65% cell viability at 25 µM). Finally, this study represents the first identification of an antimicrobial peptide in Crotalus aquilus, which belongs to the cathelicidin family and exhibits the characteristic features of these peptides. Both Aq-CATH and its derived molecule, Vcn-23, displayed remarkable inhibitory activity against all tested bacteria, highlighting their potential as promising candidates for further antimicrobial research.

Edaphic properties as pieces of evidence of tailings deposit on soils.

Mine tailings are one of the primary contaminant sources of heavy metals and metalloids in the soil. Besides increasing the concentration of potentially toxic elements (PTEs), tailings may modify the edaphic conditions and decrease the buffer capacity of impacted soils. The influence of tailings may reach distances far from the impoundments depending on the transport path and the specific transport mean: air, rain (runoff and infiltration), or acid mine drainage. In this study, soil samples from various horizons were collected in trial pits along a transect, at different distances from sulfide tailings. Soil analysis included texture, organic matter, alkalinity, porous space, carbonates, pH, electrical conductivity, real density, apparent density, total sulfur, main mineralogy, and total concentrations of As, Cd, Pb, Fe, and Zn. Graphical and statistical interpretation of the results showed that real density and porous space are the leading indicators of the tailings dispersion and accumulation and that pH is not a significant parameter (all values were above the neutrality) due to the limestone abundance in the area. However, Zn and Cd concentrations had an inverse relation with pH. Differences in the concentrations of PTEs between the superficial and deep layers that increased toward the tailings were also observed. Gypsum was only present in the closest samples to the tailings and may also be an indicator of tailings' influence on soils. This study allowed us to identify general edaphic parameters as a first and quick means to determine the tailings contamination of soils.

Vasodilator activity of Poecilotheria ornata venom involves activation of the NO/cGMP pathway and inhibition of calcium influx to vascular smooth muscle cells.

Tarantula venoms may be a natural source of new vasodilator components useful in pharmacological research. Moreover, biological function data of the venoms are important to enhance the knowledge about the biodiversity and evolution of these species. The present study aims to describe the vasodilatory activity induced by the venom of Poecilotheria ornata on isolated rat aortic rings. This venom induced a vasodilator activity that was significantly reduced after incubation with L-NAME or ODQ. Measurements of nitrite concentrations on rat aorta homogenates showed that the venom significantly increased the basal levels. Moreover, the venom attenuates the contraction induced by calcium. These results suggest that P. ornata venom contains a mixture of vasodilator components that act through the activation of the nitric oxide/cGMP pathway, as well as, through an endothelium-independent mechanism that involves the calcium influx into vascular smooth muscle cells.

Molecular basis of Q-length selectivity for the MW1 antibody-huntingtin interaction.

Huntington's disease is caused by a polyglutamine (polyQ) expansion in the huntingtin protein. Huntingtin exon 1 (Httex1), as well as other naturally occurring N-terminal huntingtin fragments with expanded polyQ are prone to aggregation, forming potentially cytotoxic oligomers and fibrils. Antibodies and other N-terminal huntingtin binders are widely explored as biomarkers and possible aggregation-inhibiting therapeutics. A monoclonal antibody, MW1, is known to preferentially bind to huntingtin fragments with expanded polyQ lengths, but the molecular basis of the polyQ length specificity remains poorly understood. Using solution NMR, electron paramagnetic resonance, and other biophysical methods, we investigated the structural features of the Httex1-MW1 interaction. Rather than recognizing residual α-helical structure, which is promoted by expanded Q-lengths, MW1 caused the formation of a new, non-native, conformation in which the entire polyQ is largely extended. This non-native polyQ structure allowed the formation of large mixed Httex1-MW1 multimers (600-2900 kD), when Httex1 with pathogenic Q-length (Q46) was used. We propose that these multivalent, entropically favored interactions, are available only to proteins with longer Q-lengths and represent a major factor governing the Q-length preference of MW1. The present study reveals that it is possible to target proteins with longer Q-lengths without having to stabilize a natively favored conformation. Such mechanisms could be exploited in the design of other Q-length specific binders.

Hydrochemistry and stable isotopes revealed focused and diffuse recharge processes in the Sonora River basin, Mexico.

A hydro-geochemical characterization was conducted in the northern part of the Sonora River basin, covering an area of 9400 km2. Equipotential lines indicated that groundwater circulation coincided with the surface water flow direction. Based on the groundwater temperature measured (on average ∼21 °C), only one spring exhibited thermalism (51 °C). Electrical conductivity (160-1750 µS/cm), chloride and nitrate concentrations (>10 and >45 mg/L) imply highly ionized water and anthropogenic pollution. In the river network, δ18O values revealed a clear modern meteoric origin. Focused recharge occurred mainly from the riverbeds during the rainy season. During the dry season, diffuse recharge was characterized by complex return flows from irrigation, urban, agricultural, mining, and livestock. Drilled wells (>50 m) exhibited a strong meteoric origin from higher elevations during the rainy season with minimal hydrochemical anomalies. Our results contribute to the knowledge of mountain-front and mountain-block recharge processes in a semi-arid and human-altered landscape in northern Mexico, historically characterized by limited hydrogeological data.

Association Between Achieved Low-Density Lipoprotein Cholesterol Levels and Long-Term Cardiovascular and Safety Outcomes: An Analysis of FOURIER-OLE.

BACKGROUND: Low-density lipoprotein cholesterol (LDL-C) is a well-established risk factor for atherosclerotic cardiovascular disease. However, the optimal achieved LDL-C level with regard to efficacy and safety in the long term remains unknown. METHODS: In FOURIER (Further Cardiovascular Outcomes Research With PCSK9 Inhibition in Subjects With Elevated Risk), 27 564 patients with stable atherosclerotic cardiovascular disease were randomized to evolocumab versus placebo, with a median follow-up of 2.2 years. In the open-label extension (FOURIER-OLE), 6635 of these patients were transitioned to open-label evolocumab regardless of initial treatment allocation in the parent trial and were followed for an additional median of 5 years. In this prespecified analysis, we examined the relationship between achieved LDL-C levels (an average of the first 2 LDL-C levels measured) in FOURIER-OLE (available in 6559 patients) and the incidence of subsequent cardiovascular and safety outcomes. We also performed sensitivity analyses evaluating cardiovascular and safety outcomes in the entire FOURIER and FOURIER-OLE patient population. Multivariable modeling was used to adjust for baseline factors associated with achieved LDL-C levels. RESULTS: In FOURIER-OLE, 1604 (24%), 2627 (40%), 1031 (16%), 486 (7%), and 811 (12%) patients achieved LDL-C levels of <20, 20 to <40, 40 to <55, 55 to <70, and ≥70 mg/dL, respectively. There was a monotonic relationship between lower achieved LDL-C levels-down to very low levels <20 mg/dL-and a lower risk of the primary efficacy end point (composite of cardiovascular death, myocardial infarction, stroke, hospital admission for unstable angina or coronary revascularization) and the key secondary efficacy end point (composite of cardiovascular death, myocardial infarction, or stroke) that persisted after multivariable adjustment (adjusted Ptrend<0.0001 for each end points). No statistically significant associations existed in the primary analyses between lower achieved LDL-C levels and increased risk of the safety outcomes (serious adverse events, new or recurrent cancer, cataract-related adverse events, hemorrhagic stroke, new-onset diabetes, neurocognitive adverse events, muscle-related events, or noncardiovascular death). Similar findings were noted in the entire FOURIER and FOURIER-OLE cohort up to a maximum follow-up of 8.6 years. CONCLUSIONS: In patients with atherosclerotic cardiovascular disease, long-term achievement of lower LDL-C levels, down to <20 mg/dL (<0.5 mmol/L), was associated with a lower risk of cardiovascular outcomes with no significant safety concerns. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT01764633.

Fluoride presence in drinking water along the southeastern part of El Bajío Guanajuatense, Guanajuato, Mexico: sources and health effects.

Drinking water with a high natural concentration of fluoride (F-) has serious consequences for the health of the rural population in the state of Guanajuato, Mexico, where the water contains levels of F- that are not allowed by national and international regulations (1.5 mg/L). This health problem is very common in multiple states throughout Mexico where drinking water is generally extracted from aquifers that are hosted in fractured volcanic rocks of the Tertiary. These aquifers show similar geological characteristics: deep basins that formed as a result of felsic eruptive events and the extensional deformation of the Basin and Range and are now filled with unconsolidated sediments. In this study, we assessed the occurrence of F in volcanic rocks collected at 11 sampling sites along the Sierra de Codornices in Guanajuato (ranging between 0.01299 and 0.146 wt%, average 0.039 wt%, and SD = 0.039 wt%; n = 10), a region where both rural and urban communities consume drinking water with a high F- content (up to 7.1 (mg/L). The F content is dispersed in volcanic rocks, and the highest levels are present in felsic rocks. The statistical and hydrogeochemical results of a sampling campaign of 32 wells in the Juventino Rosas (JR) and Villagran (Vill) municipalities in 2019 suggest that F- mobilization in groundwater is the product of silicate weathering and the dissolution of volcanic glass, alkaline desorption in the surfaces of F-containing minerals, and possibly ion exchange of minerals and clays or deep fluids enriched with F-, in addition to the precipitation of carbonates that decrease the Ca2+ concentration in groundwater. All of these processes can be accelerated by groundwater geothermal characteristics within the study area. The hydrogeochemical, fluoride exposure risk, and fluoride pollution index (FPI) results, as well as the epidemiological survey, indicate that teenagers and older adults from Praderas de la Venta are at risk of exposure to F- due to the high concentrations ingested over a long period, the toxicity of the element, and its ability to accumulate in the bones. Extended exposure to elevated levels increases the risk. This work allows us to observe how the populations of JR and Vill can be exposed to high F- contents in drinking water due to the geological characteristics of the region.