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1.
BMC Public Health ; 24(1): 2057, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39085807

RESUMEN

BACKGROUND: The COVID-19 pandemic has significantly impacted education systems worldwide, with Brazil being one of the countries with the longest school closures. Over a million children and teenagers have been affected, leading to increased hunger and nutritional deficiencies. This study aimed to implement long-term surveillance of SARS-CoV-2 infections in public and private schools in Campo Grande, Brazil, after returning to in-person classes. METHODS: The study involved testing and genomic surveillance at 23 public and private schools in Campo Grande, Mato Grosso do Sul, Brazil, from October 18, 2021 to November 21, 2022. The participants eligible for enrollment were students aged 6-17 years and staff members from school institutions. At the time of collection, participants were asked if they had symptoms in the last two weeks. Whole-genome sequencing of SARS-CoV-2 was conducted to identify circulating variants and to compare them with those detected in the municipality. The demographic data and clinical history of the participants were described, and a logistic regression model was used to understand how the RT-qPCR results could be related to different characteristics. RESULTS: The study included 999 participants, most of whom were women. A total of 85 tests were positive, with an overall positivity rate of 3.2%. The dynamics of case frequency were consistent with those observed in the municipality during the study period. The most common symptoms reported were cough, rhinorrhea, headache, and sore throat. Symptoms were significantly associated with SARS-CoV-2 infection. Eleven lineages were identified in school community samples, with a frequency of occurrence per period similar to that found in the sequences available for the municipality. The most prevalent lineages within the sampling period were BA.2 (59.3%) and BA.5 (29.6%). CONCLUSIONS: Our findings demonstrate that schools can play a crucial role in epidemiological surveillance, helping trigger rapid responses to pathogens such as SARS-CoV-2. Long-term surveillance can be used to track outbreaks and assess the role of children and adults in transmission. It can also contribute to pandemic preparedness, enabling a rapid response to emergencies, such as COVID-19.


Asunto(s)
COVID-19 , SARS-CoV-2 , Instituciones Académicas , Humanos , COVID-19/epidemiología , COVID-19/diagnóstico , Brasil/epidemiología , Adolescente , Niño , Masculino , Femenino , Secuenciación Completa del Genoma
2.
Reprod Domest Anim ; 59(1): e14510, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38013657

RESUMEN

While sperm migrate within the reproductive tract of cows experiencing negative energy balance (NEB), they come into contact with elevated concentrations of non-esterified fatty acids (NEFA). For this reason, this study aimed to investigate the effects of three different NEFA - palmitic acid (PA), stearic acid (SA), and oleic acid (OA) - on bovine sperm motility, kinetic parameters, oxidative status, and morphology. Frozen thawed semen samples from Bos taurus bulls were incubated with varying concentrations of each fatty acid, and the sperm's characteristics were analysed at different time points. Computer-Assisted Sperm Analysis (CASA) was employed to assess sperm motility and kinetic parameters. Concurrently, the production of the reactive oxygen species (ROS) and total antioxidant capacity were measured to determine the oxidative status. Additionally, sperm morphology was evaluated. In Experiment 1, different concentrations of PA did not show significant effects on total motility, progressive motility, or any kinetic parameters analysed. Similarly, PA did not have a significant impact on the oxidative status or sperm morphology. In Experiment 2, SA at various concentrations did not lead to significant changes in total motility, progressive motility, or any kinetic parameters evaluated. Furthermore, SA did not affect oxidative status or sperm morphology. In Experiment 3, the concentrations of OA used did not result in significant changes in total motility, progressive motility, or any kinetic parameters studied. Likewise, OA did not induce any alterations in oxidative status or sperm morphology. Overall, the results from all three experiments indicate that PA, SA and OA, at the in vitro conditions and tested concentrations, do not exert detrimental effects on bovine sperm function and morphology. These results provide insights that contribute to our understanding of how fatty acids can impact the reduction of fertility rates in cows facing NEB. This, in turn, lays the foundation for additional critical investigations in this area. Further studies are necessary to validate these findings in vivo.


Asunto(s)
Preservación de Semen , Semen , Femenino , Bovinos , Masculino , Animales , Ácidos Grasos , Motilidad Espermática , Ácidos Grasos no Esterificados , Espermatozoides , Preservación de Semen/veterinaria , Estrés Oxidativo
3.
Inflamm Res ; 72(10-11): 1933-1940, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36416944

RESUMEN

OBJECTIVE AND DESIGN: The heterogeneity of response to SARS-CoV-2 infection is directly linked to the individual genetic background. Genetic variants of inflammasome-related genes have been pointed as risk factors for several inflammatory sterile and infectious disease. In the group of inflammasome receptors, NLRP1 stands out as a good novel candidate as severity factor for COVID-19 disease. METHODS: To address this question, we performed an association study of NLRP1, DPP9, CARD8, IL1B, and IL18 single nucleotide variants (SNVs) in a cohort of 945 COVID-19 patients. RESULTS: The NLRP1 p.Leu155His in the linker region, target of viral protease, was significantly associated to COVID-19 severity, which could contribute to the excessive cytokine release reported in severe cases. CONCLUSION: Inflammasome genetic background contributes to individual response to SARS-CoV-2.


Asunto(s)
COVID-19 , Inflamasomas , Humanos , Inflamasomas/genética , Inflamasomas/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , COVID-19/genética , Proteínas NLR/genética , SARS-CoV-2/metabolismo , Proteínas de Neoplasias/genética , Proteínas Adaptadoras de Señalización CARD/genética
4.
Proc Biol Sci ; 289(1982): 20220980, 2022 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-36100020

RESUMEN

Although numerous studies about camouflage have been conducted in the last few decades, there is still a significant gap in our knowledge about the magnitude of protective value of different camouflage strategies in prey detection and survival. Furthermore, the functional significance of several camouflage strategies remains controversial. Here we carried out a comprehensive meta-analysis including comparisons of different camouflage strategies as well as predator and prey types, considering two response variables: mean predator search time (ST) (63 studies) and predator attack rate (AR) of camouflaged prey (28 studies). Overall, camouflage increased the predator ST by 62.56% and decreased the AR of prey by 27.34%. Masquerade was the camouflage strategy that most increased predator ST (295.43%). Background matching and disruptive coloration did not differ from each other. Motion camouflage did not increase ST but decreases AR on prey. We found no evidence that eyespot increases ST and decreases AR by predators. The different types of predators did not differ from each other, but caterpillars were the type of prey that most influenced the magnitude of camouflage's effect. We highlight the potential evolutionary mechanisms that led camouflage to be a highly effective anti-predatory adaptation, as well as potential discrepancies or redundancies among strategies, predator and prey types.


Asunto(s)
Evolución Biológica , Conducta Predatoria , Adaptación Fisiológica , Animales , Movimiento (Física) , Conducta Predatoria/fisiología
5.
Glob Chang Biol ; 28(11): 3694-3710, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35243726

RESUMEN

Current climate change is disrupting biotic interactions and eroding biodiversity worldwide. However, species sensitive to aridity, high temperatures, and climate variability might find shelter in microclimatic refuges, such as leaf rolls built by arthropods. To explore how the importance of leaf shelters for terrestrial arthropods changes with latitude, elevation, and climate, we conducted a distributed experiment comparing arthropods in leaf rolls versus control leaves across 52 sites along an 11,790 km latitudinal gradient. We then probed the impact of short- versus long-term climatic impacts on roll use, by comparing the relative impact of conditions during the experiment versus average, baseline conditions at the site. Leaf shelters supported larger organisms and higher arthropod biomass and species diversity than non-rolled control leaves. However, the magnitude of the leaf rolls' effect differed between long- and short-term climate conditions, metrics (species richness, biomass, and body size), and trophic groups (predators vs. herbivores). The effect of leaf rolls on predator richness was influenced only by baseline climate, increasing in magnitude in regions experiencing increased long-term aridity, regardless of latitude, elevation, and weather during the experiment. This suggests that shelter use by predators may be innate, and thus, driven by natural selection. In contrast, the effect of leaf rolls on predator biomass and predator body size decreased with increasing temperature, and increased with increasing precipitation, respectively, during the experiment. The magnitude of shelter usage by herbivores increased with the abundance of predators and decreased with increasing temperature during the experiment. Taken together, these results highlight that leaf roll use may have both proximal and ultimate causes. Projected increases in climate variability and aridity are, therefore, likely to increase the importance of biotic refugia in mitigating the effects of climate change on species persistence.


Asunto(s)
Artrópodos , Animales , Biodiversidad , Cambio Climático , Ecosistema , Hojas de la Planta
6.
Biol Sport ; 39(3): 745-749, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35959322

RESUMEN

Capillary dried blood spot (DBS) samples facilitate field-based collection without venipuncture. This pilot study aims to evaluate the viability of creatine (Cr) and creatinine (Crt) quantification using fresh capillary serum (CrS/CrtS) and DBS samples (CrDBS/CrtDBS), using Flow Injection Analysis Mass Spectrometry (FIA - MS). Nine Olympic Athletes provided a capillary blood sample to assess CrS/CrtS and CrDBS/CrtDBS quantified by FIA - MS. No difference between CrtS (mean ± SD: 813.6 ± 102.4 µmol/L) and CrtDBS (812.4 ± 108.1 µmol/L) was observed with acceptable variance [SEM 88.7; CV 10.7%; ICC 0.57 (CI 95% 0.06 - 0.84)] and agreement [very strong (Spearman: r = 0.77; p < 0.01) or strong (Pearson: r = 0.56; p = 0.04); Bland Altman: lower (-193) and upper (+196) limits of agreement]. CrS (mean ± SD: 691.8 ± 165.2 µmol/L) was significantly different to CrDBS (2911 ± 571.4 µmol/L) with unacceptable variance [SEM 171.6; CV 27%; ICC 0.002 (CI 95% -0.02 - 0.07)] and 'weak' agreement [Spearman: r = 0.21, p = 0.47 and Pearson: r = 0.06, p = 0.84; Bland Altman lower (-3367) and upper (-1072) limits of agreement]. Crt quantification is viable using both CrtS and CrtDBS (but not for Cr and CrS/CrDBS), with the DBS tissue handling technique offering several methodological and practice facing advantages. Future work should expand upon the sample size, explore sport/discipline relevant analytes across a full competitive season, including key training, recovery and performance blocks of their periodized performance plan.

7.
Oecologia ; 192(3): 745-753, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32016526

RESUMEN

Biotic and abiotic factors may individually or interactively disrupt plant-pollinator interactions, influencing plant fitness. Although variations in temperature and precipitation are expected to modify the overall impact of predators on plant-pollinator interactions, few empirical studies have assessed if these weather conditions influence anti-predator behaviors and how this context-dependent response may cascade down to plant fitness. To answer this question, we manipulated predation risk (using artificial spiders) in different years to investigate how natural variation in temperature and precipitation may affect diversity (richness and composition) and behavioral (visitation) responses of flower-visiting insects to predation risk, and how these effects influence plant fitness. Our findings indicate that predation risk and an increase in precipitation independently reduced plant fitness (i.e., seed set) by decreasing flower visitation. Predation risk reduced pollinator visitation and richness, and altered species composition of pollinators. Additionally, an increase in precipitation was associated with lower flower visitation and pollinator richness but did not alter pollinator species composition. However, maximum daily temperature did not affect any component of the pollinator assemblage or plant fitness. Our results indicate that biotic and abiotic drivers have different impacts on pollinator behavior and diversity with consequences for plant fitness components. Even small variation in precipitation conditions promotes complex and substantial cascading effects on plants by affecting both pollinator communities and the outcome of plant-pollinator interactions. Tropical communities are expected to be highly susceptible to climatic changes, and these changes may have drastic consequences for biotic interactions in the tropics.


Asunto(s)
Polinización , Conducta Predatoria , Animales , Flores , Insectos , Plantas
8.
Skin Pharmacol Physiol ; 32(1): 32-42, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30380537

RESUMEN

AIM: We evaluated the effects of the incorporation of zinc oxide (ZnO) nanoparticles in a mesoporous matrix, aiming to improve the textural, structural and morphological properties and verify their safety so that they can be applied in sunscreen cosmetics. MATERIALS AND METHODS: ZnO nano-particles were incorporated into an ordered mesoporous silica matrix known as Santa Barbara Amorphous-15 (SBA-15), using post-synthesis methodology. The resulting nanocomposites were characterized using X-ray diffraction, small angle X-ray scattering, N2 adsorption-desorption isotherms, Fourier transform infrared spectroscopy, scanning electron microscopy and predicted in vitro sun protector factor (SPF) estimation. Effectiveness and safety were evaluated by antimicrobial activity, in vitro cell toxicity and non-invasive multi-photon tomography with fluorescence lifetime imaging. RESULTS: The structure of the nanocomposites was similar to that of SBA-15, with little perturbation caused by ZnO incorporation. Nanocomposites had an increased in vitro SPF, reduced cytotoxic activity and favourable antimicrobial properties compared to ZnO. ZnO:SBA-15 nanocomposites exhibited no measurable toxicity when applied to human skin in vivo. CONCLUSION: Due to their suitable physicochemical properties and improved safety compared to bare ZnO nanoparticles, the ZnO:SBA-15 nanocomposites show promise for use in cosmetic applications.


Asunto(s)
Composición de Medicamentos/métodos , Nanocompuestos/administración & dosificación , Dióxido de Silicio/administración & dosificación , Absorción Cutánea/efectos de los fármacos , Protectores Solares/administración & dosificación , Óxido de Zinc/administración & dosificación , Adulto , Animales , Células 3T3 BALB , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Relación Dosis-Respuesta a Droga , Portadores de Fármacos/administración & dosificación , Portadores de Fármacos/síntesis química , Portadores de Fármacos/metabolismo , Combinación de Medicamentos , Humanos , Ratones , Nanocompuestos/química , Dióxido de Silicio/síntesis química , Dióxido de Silicio/metabolismo , Absorción Cutánea/fisiología , Protectores Solares/síntesis química , Protectores Solares/metabolismo , Pruebas de Toxicidad Aguda/métodos , Difracción de Rayos X/métodos , Adulto Joven , Óxido de Zinc/síntesis química , Óxido de Zinc/metabolismo
9.
J Sep Sci ; 41(21): 4047-4054, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30168667

RESUMEN

In this study, the viability of applying cork and montmorillonite clay modified with ionic liquid as biosorbents in the rotating-disk sorptive extraction technique was investigated. Specifically, this was aimed at the determination of methyl paraben, ethyl paraben, propyl paraben, and isobutyl paraben, with separation/determination by high-performance liquid chromatography coupled with mass spectrometry. The optimization of the method for both biosorbents was performed using multivariate procedures. The extraction efficiencies for the target compounds in aqueous matrices were compared to those obtained using the commercial sorbent Octadecil Silano-C18. The optimum extraction conditions for both natural sorbents were the use of an ammonia solution (pH 10) as desorption solvent and an extraction time of 30 min. The proposed methods show limits of quantification of 0.8 µg/L for cork, 3.0 µg/L for montmorillonite clay and 6.0 µg/L for Octadecil Silano-C18. The relative recoveries from river water and tap water samples ranged from 80.3 to 118.7% and 80.0 to 119.9% for cork and montmorillonite clay modified with ionic liquid, respectively. Relative standard deviations were obtained for intra- and interday precisions of <15% and <19% for cork and <19% and <17% for montmorillonite clay modified with ionic liquid.

10.
J Craniofac Surg ; 29(2): e209-e211, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29227411

RESUMEN

BACKGROUND: Intraoral pleomorphic adenoma (PA) is rare in young individuals, with only single clinical reports or small patient series reported previously. AIM: The aim of this study was to describe the clinicopathological features of PA in 4 patients under 18 years of age, and to discuss the differential diagnosis of pediatric patients presenting with intraoral submucosal nodules. METHODS: Between 2000 and 2015, all patients of intraoral PA in patients aged ≤18 years diagnosed in the Oral Pathology Laboratory of the Universidade Federal de Pernambuco, Brazil, were retrieved for the study. Clinical data were recorded from the clinical charts. Histopathological slides stained with hematoxylin and eosin were reviewed to confirm the diagnosis. RESULTS: There were 4 cases of PA in patients aged ≤18 years. All patients in this patient series were males, with a mean age of 16.7 years. Three cases occurred in the palate, and in 1 case, the upper lip was affected. All PAs appeared as a painless, smooth surface, well-circumscribed, and submucosal nodule. All patients were surgically excised and subsequent histopathological analysis revealed well-circumscribed tumors composed of cells that were arranged in ducts within a fibromyxoid stroma. No signs of recurrence were observed in 3 patients after a mean follow-up of 30 months. One patient is lost to follow-up. CONCLUSION: Although PAs are unusual in young patients, they should be considered in the differential diagnosis of oral submucosal nodules.


Asunto(s)
Adenoma Pleomórfico/cirugía , Neoplasias de la Boca/cirugía , Adenoma Pleomórfico/patología , Adolescente , Femenino , Humanos , Labio , Masculino , Neoplasias de la Boca/patología , Hueso Paladar
11.
J Environ Manage ; 221: 10-19, 2018 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-29787968

RESUMEN

Quality reference values (QRV) for potentially toxic elements (PTE) in soils are established as a tool for prevention and monitoring of soil pollution. These values should be periodically revised in order to ensure soil safety for agricultural purposes. Brazil is market leader for several commodities; therefore, the safety of Brazilian soils is of worldwide strategic importance. The objective of this study was to determine the natural background concentrations and the QRV for As, Ba, Cd, Cr, Ni, Pb, Se, and Zn by investigating 30 representative pedotypes in the São Paulo State, one of the most important agro-industry economy at worldwide level. Multivariate statistical analysis was applied to determine the sources of PTE and their variability. The mean natural background concentrations of PTE in the soils were generally lower to those reported in literature. QRV, calculated for each element as the 75th and 90th percentiles, were lower (75th for As, Cd, Pb, and Zn), similar (75th for Ba, Cr, and Se) or above (90th for Ba, Cr, and Se and 75-90th for Ni) those previously proposed by the Brazilian environmental protection agencies. The results indicate that 75th percentile may be too restrictive. The PTE in the investigated soils appear to have comes mainly from two primary natural sources: a prevalent one of geogenic and a secondary of pedogenic origin. These results confirm the predominant natural source of selected PTE in the investigated soils, thus sustaining the possibility of using the data set to develop QRV for the State of São Paulo.


Asunto(s)
Metales Pesados/análisis , Contaminantes del Suelo/análisis , Brasil , Monitoreo del Ambiente , Valores de Referencia , Suelo
12.
AAPS PharmSciTech ; 18(5): 1739-1749, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27757922

RESUMEN

In this study, non-aqueous microemulsions were developed because of the challenges associated with finding pharmaceutically acceptable solvents for topical delivery of drugs sparingly soluble in water. The formulation irritation potential and ability to modulate the penetration of lipophilic compounds (progesterone, α-tocopherol, and lycopene) of interest for topical treatment/prevention of skin disorders were evaluated and compared to solutions and aqueous microemulsions of similar composition. The microemulsions (ME) were developed with BRIJ, vitamin E-TPGS, and ethanol as surfactant-co-surfactant blend and tributyrin, isopropyl myristate, and oleic acid as oil phase. As polar phase, propylene glycol (MEPG) or water (MEW) was used (26% w/w). The microemulsions were isotropic and based on viscosity and conductivity assessment, bicontinuous. Compared to drug solutions in lipophilic vehicles, MEPG improved drug delivery into viable skin layers by 2.5-38-fold; the magnitude of penetration enhancement mediated by MEPG into viable skin increased with drug lipophilicity, even though the absolute amount of drug delivered decreased. Delivery of progesterone and tocopherol, but not lycopene (the most lipophilic compound), increased up to 2.5-fold with MEW, and higher amounts of these two drugs were released from MEW (2-2.5-fold). Both microemulsions were considered safe for topical application, but MEPG-mediated decrease in the viability of reconstructed epidermis was more pronounced, suggesting its higher potential for irritation. We conclude that MEPG is a safe and suitable nanocarrier to deliver a variety of lipophilic drugs into viable skin layers, but the use of MEW might be more advantageous for drugs in the lower range of lipophilicity.


Asunto(s)
Sistemas de Liberación de Medicamentos/métodos , Absorción Cutánea/efectos de los fármacos , Tensoactivos/administración & dosificación , Administración Cutánea , Administración Tópica , Animales , Carotenoides/administración & dosificación , Carotenoides/metabolismo , Emulsiones/administración & dosificación , Metabolismo de los Lípidos/efectos de los fármacos , Metabolismo de los Lípidos/fisiología , Lípidos/administración & dosificación , Licopeno , Propilenglicol/administración & dosificación , Propilenglicol/metabolismo , Piel/metabolismo , Absorción Cutánea/fisiología , Tensoactivos/metabolismo , Porcinos , Viscosidad , alfa-Tocoferol/administración & dosificación , alfa-Tocoferol/metabolismo
13.
Biomedicines ; 12(1)2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38255318

RESUMEN

Leishmaniasis remains a significant global health concern, with current treatments relying on outdated drugs associated with high toxicity, lengthy administration, elevated costs, and drug resistance. Consequently, the urgent need for safer and more effective therapeutic options in leishmaniasis treatment persists. Previous research has highlighted selenium compounds as promising candidates for innovative leishmaniasis therapy. In light of this, a library of 10 selenium-containing diverse compounds was designed and evaluated in this study. These compounds included selenium-substituted indole, coumarin, chromone, oxadiazole, imidazo[1,2-a]pyridine, Imidazo[2,1-b]thiazole, and oxazole, among others. These compounds were screened against Leishmania amazonensis promastigotes and intracellular amastigotes, and their cytotoxicity was assessed in peritoneal macrophages, NIH/3T3, and J774A.1 cells. Among the tested compounds, MRK-106 and MRK-108 displayed the highest potency against L. amazonensis promastigotes with reduced cytotoxicity. Notably, MRK-106 and MRK-108 exhibited IC50 values of 3.97 µM and 4.23 µM, respectively, and most of the tested compounds showed low cytotoxicity in host cells (CC50 > 200 µM). Also, compounds MRK-107 and MRK-113 showed activity against intracellular amastigotes (IC50 18.31 and 15.93 µM and SI 12.55 and 10.92, respectively). In conclusion, the identified selenium-containing compounds hold potential structures as antileishmanial drug candidates to be further explored in subsequent studies. These findings represent a significant step toward the development of safer and more effective therapies for leishmaniasis, addressing the pressing need for novel and improved treatments.

14.
Ecology ; 94(7): 1510-8, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23951711

RESUMEN

Ecosystem engineering is a process by which organisms change the distribution of resources and create new habitats for other species via non-trophic interactions. Leaf-rolling caterpillars can act as ecosystem engineers because they provide shelter to secondary users. In this study, we report the influence of leaf-rolling caterpillars on speciose tropical arthropod communities along both spatial scales (leaf-level and plant-level effects) and temporal scales (dry and rainy seasons). We predict that rolled leaves can amplify arthropod diversity at both the leaf and plant levels and that this effect is stronger in dry seasons, when arthropods are prone to desiccation. Our results show that the abundance, richness, and biomass of arthropods within several guilds increased up to 22-fold in naturally and artificially created leaf shelters relative to unaltered leaves. These effects were observed at similar magnitudes at both the leaf and plant scales. Variation in the shelter architecture (funnel, cylinders) did not influence arthropod parameters, as diversity, abundance, orbiomass, but rolled leaves had distinct species composition if compared with unaltered leaves. As expected, these arthropod parameters on the plants with rolled leaves were on average approximately twofold higher in the dry season. Empty leaf rolls and whole plants were rapidly recolonized by arthropods over time, implying a fast replacement of individuals; within 15-day intervals the rolls and plants reached a species saturation. This study is the first to examine the extended effects of engineering caterpillars as diversity amplifiers at different temporal and spatial scales. Because shelter-building caterpillars are ubiquitous organisms in tropical and temperate forests, they can be considered key structuring elements for arthropod communities on plants.


Asunto(s)
Artrópodos/fisiología , Conducta Animal/fisiología , Ecosistema , Hojas de la Planta , Animales , Demografía , Larva/fisiología , Factores de Tiempo
15.
Sci Rep ; 13(1): 19985, 2023 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-37968331

RESUMEN

Background matching and disruptive coloration are common camouflage strategies in nature, but few studies have accurately measured their protective value in living organisms. Amazon's Bark praying mantises exhibit colour patterns matching whitish and greenish-brown tree trunks. We tested the functional significance of background matching and disruptive coloration of different praying mantis morphospecies (white, grey and green) detected by DNA barcoding. Through image analysis, avian visual models and field experiments using humans as potential predators, we explored whether the background occupation of mantises provides camouflage against predation. Data were obtained for individuals against their occupied tree trunks (whitish or greenish-brown) and microhabitats (lichen or bryophyte patches), compared to non-occupied trunks. White and grey mantises showed lower colour contrasts against occupied trunks at the scale of tree trunk, with no differences in luminance contrasts. Conversely, green mantises showed lower colour and luminance contrasts against microhabitats and also exhibited high edge disruption against greenish-brown trunks. The camouflage of white and green mantis models against colour-matching trunks increased search time and reduced encounter distance of human predators. We highlight the importance of camouflage strategies at different spatial scales to enhance individual survival against predators. Specifically, we present a stunning study system to investigate the relationship of phylogenetically related species that use camouflage in sympatry.


Asunto(s)
Mantódeos , Animales , Humanos , Corteza de la Planta , Simpatría , Color , Visión Ocular , Conducta Predatoria , Pigmentación
16.
Virus Res ; 318: 198850, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35750131

RESUMEN

The human Respiratory Syncytial Virus (hRSV) is the main causative agent of acute respiratory infections (ARI), such as pneumonia and bronchiolitis. One of the factors that lead to success in viral replication is the interaction of the M2-2 protein with the ribosomal complex. This interaction is responsible for the phase change of viral activity, acting as an inhibitor or inducer of viral replication, according to the concentration of mRNA. Based on the importance of M2-2 gene and protein have to viral physiology, we performed here evaluations of genetic diversity, phylogenetic reconstructions, phylodynamics, and selection test. Our results suggested an alternative way of classifying this virus in clades A and B, based on a new phylogenetic marker, the M2-2 gene. Therefore, our study is the first one to investigate the dynamics of the evolutionary diversification process of hRSV from the perspective of the M2-2 viral gene. In our study was also identified that the M2-2 gene is under the effect of purifying selection originated by population genetic bottlenecks. Therefore, the M2-2 gene demonstrated an interesting potential to be applied in evolutionary studies involving hRSV, recovering phylogenetic signals and traits of natural selection under the evolution of this virus.


Asunto(s)
Filogenia , Infecciones por Virus Sincitial Respiratorio , Virus Sincitial Respiratorio Humano , Genes Virales , Humanos , Infecciones por Virus Sincitial Respiratorio/epidemiología , Infecciones por Virus Sincitial Respiratorio/genética , Virus Sincitial Respiratorio Humano/genética , Selección Genética , Proteínas Virales
17.
Anim Reprod Sci ; 243: 107033, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35816934

RESUMEN

Metabolic stress conditions caused by negative energy balance (NEB) have been associated with reduced fertility in cows. ß-hydroxybutyrate (BHBA) is the main circulating ketone body, which accumulates within follicular fluid. The aim of this study was to evaluate the effects of BHBA on follicle growth and on ovulatory mechanisms in cattle. At 72 h after intrafollicular injection, there was a decrease in follicular diameter in BHBA group compared to control (P = 0.02). Furthermore, follicle growth rate was reduced post-treatment with BHBA in comparison to the control group (P < 0.03). The BHBA intrafollicular injection in follicles ≥ 12 mm, however, did not affect E2 and P4 concentrations in the follicular fluid. In addition, the relative abundance of genes involved in the ovulatory cascade (ADAM 17, AREG, EREG, PTGS2), steroidogenesis (CYP19A1, 3BHSD, STAR), cellular stress (SOD1, CAT, GPX1, HSPA5, XBP1s, XBP1u, ATF4, ATF6), monocarboxylic acid transporters (SLC16A1, SLC16A7) and apoptosis (XIAP) was similar between groups. In conclusion, the results of this study indicate that the increase in intrafollicular concentrations of BHBA affects follicular growth, but it does not compromise the ovulatory cascade and cellular homeostasis in bovine granulosa cells.


Asunto(s)
Células de la Granulosa , Folículo Ovárico , Ácido 3-Hidroxibutírico/metabolismo , Animales , Bovinos , Femenino , Fertilidad , Líquido Folicular , Células de la Granulosa/metabolismo
18.
Ecology ; 103(4): e3639, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35060615

RESUMEN

The construction of shelters on plants by arthropods might influence other organisms via changes in colonization, community richness, species composition, and functionality. Arthropods, including beetles, caterpillars, sawflies, spiders, and wasps often interact with host plants via the construction of shelters, building a variety of structures such as leaf ties, tents, rolls, and bags; leaf and stem galls, and hollowed out stems. Such constructs might have both an adaptive value in terms of protection (i.e., serve as shelters) but may also exert a strong influence on terrestrial community diversity in the engineered and neighboring hosts via colonization by secondary occupants. Although different traits of the host plant (e.g., physical, chemical, and architectural features) may affect the potential for ecosystem engineering by insects, such effects have been, to a certain degree, overlooked. Further analyses of how plant traits affect the occurrence of shelters may therefore enrich our understanding of the organizing principles of plant-based communities. This data set includes more than 1000 unique records of ecosystem engineering by arthropods, in the form of structures built on plants. All records have been published in the literature, and span both natural structures (91% of the records) and structures artificially created by researchers (9% of the records). The data were gathered between 1932 and 2021, across more than 50 countries and several ecosystems, ranging from polar to tropical zones. In addition to data on host plants and engineers, we aggregated data on the type of constructs and the identity of inquilines using these structures. This data set highlights the importance of these subtle structures for the organization of terrestrial arthropod communities, enabling hypotheses testing in ecological studies addressing ecosystem engineering and facilitation mediated by constructs. There are no copyright restrictions and please cite this paper when using the data in publications.


Asunto(s)
Artrópodos , Animales , Biodiversidad , Ecosistema , Insectos , Hojas de la Planta , Plantas
19.
Behav Processes ; 193: 104536, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34728314

RESUMEN

Orb-webs show diversity in several traits, including silk types, architecture, physical properties, locale, and period of exposition. The investigation of how they determine the identity of intercepted prey is important to functional ecology and to the evaluation of trophic niche partitioning within communities. However, the influence of several of these variables on the composition of intercepted insects remains to be determined. In this study, we evaluated the effects of web architectural traits, height, and daily periods of exposition on the interception of different insects in terms of sizes, masses, and taxa. We conducted observations of prey intercepted by the orb webs of 16 sympatric spider species and artificial webs. We found that all orb webs mainly intercepted small and light insects, sharing the most abundant insect families found in the study area. However, spiders that show nocturnal activity, more radii in their webs, large and high webs captured heavier insects. Other orb-web traits, such as the density of capture threads did not influence the kind of intercepted insects. We discuss why some variables affected prey interceptions in terms of mass. Finally, we discuss the implications of these influential variables to functional ecology, niche differentiation, and how behavioral assessments can complete this investigation in future studies.


Asunto(s)
Conducta Predatoria , Arañas , Animales , Humanos , Fenotipo , Seda
20.
Talanta ; 235: 122820, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34517675

RESUMEN

This paper presents the Outer Plug Standardization - OPS, a novel technique as an alternative for the classic internal standardization using multiple injection in capillary zone electrophoresis is proposed herein. This technique was applied in a new method for the determination of chloride, nitrate and sulfate in rainwater samples. After the injection accuracy was tested and proved to be a minor error source (average 1.26% RSD), the OPS was applied and it improved the intra-day and inter-day precision of the analytical method by 32.5% and 24.7%, respectively. Using a capillary with effective length of 23.5 cm the electrophoretic separation of the three inorganic anions could be achieved in <1 min, with detection limits of 0.05, 0.09 and 0.11 mg L-1 for chloride, nitrate and sulfate, respectively. Also, the statistical t-test was applied to the results obtained for 82 rainwater samples that were collected and analyzed applying both the method developed in this study and the official APHA 4140 method where no statistical difference was noted within a 95% confidence level.


Asunto(s)
Cloruros , Proyectos de Investigación , Aniones , Calibración , Estándares de Referencia
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