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1.
Nature ; 572(7771): 651-654, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31413362

RESUMO

The origins of endothermy in birds and mammals are important events in vertebrate evolution. Endotherms can maintain their body temperature (Tb) over a wide range of ambient temperatures primarily using the heat that is generated continuously by their high basal metabolic rate (BMR)1. There is also an important positive feedback loop as Tb influences BMR1-3. Owing to this interplay between BMRs and Tb, many ecologists and evolutionary physiologists posit that the evolution of BMR and Tb must have been coupled during the radiation of endotherms3-5, changing with similar trends6-8. However, colder historical environments might have imposed strong selective pressures on BMR to compensate for increased rates of heat loss and to keep Tb constant9-12. Thus, adaptation to cold ambient temperatures through increases in BMR could have decoupled BMR from Tb and caused different evolutionary routes to the modern diversity in these traits. Here we show that BMR and Tb were decoupled in approximately 90% of mammalian phylogenetic branches and 36% of avian phylogenetic branches. Mammalian BMRs evolved with rapid bursts but without a long-term directional trend, whereas Tb evolved mostly at a constant rate and towards colder bodies from a warmer-bodied common ancestor. Avian BMRs evolved predominantly at a constant rate and without a long-term directional trend, whereas Tb evolved with much greater rate heterogeneity and with adaptive evolution towards colder bodies. Furthermore, rapid shifts that lead to both increases and decreases in BMRs were linked to abrupt changes towards colder ambient temperatures-although only in mammals. Our results suggest that natural selection effectively exploited the diversity in mammalian BMRs under diverse, often-adverse historical thermal environments.


Assuntos
Metabolismo Basal/fisiologia , Evolução Biológica , Temperatura Corporal/fisiologia , Animais , Aves/classificação , Aves/metabolismo , Regulação da Temperatura Corporal/fisiologia , Mamíferos/classificação , Mamíferos/metabolismo , Filogenia
2.
Wound Repair Regen ; 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38794912

RESUMO

Wound healing is a complex physiological process that requires precise control and modulation of many parameters. Therapeutic ion and biomolecule delivery has the capability to regulate the wound healing process beneficially. However, achieving controlled delivery through a compact device with the ability to deliver multiple therapeutic species can be a challenge. Bioelectronic devices have emerged as a promising approach for therapeutic delivery. Here, we present a pro-reparative bioelectronic device designed to deliver ions and biomolecules for wound healing applications. The device incorporates ion pumps for the targeted delivery of H+ and zolmitriptan to the wound site. In vivo studies using a mouse model further validated the device's potential for modulating the wound environment via H+ delivery that decreased M1/M2 macrophage ratios. Overall, this bioelectronic ion pump demonstrates potential for accelerating wound healing via targeted and controlled delivery of therapeutic agents to wounds. Continued optimization and development of this device could not only lead to significant advancements in tissue repair and wound healing strategies but also reveal new physiological information about the dynamic wound environment.

3.
Am J Gastroenterol ; 118(1): 129-137, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36114773

RESUMO

INTRODUCTION: Children with inflammatory bowel disease (IBD) may respond differently to COVID-19 immunization as compared with healthy children or adults with IBD. Those younger than 12 years receive a lower vaccine dose than adults. We sought to describe the safety and humoral immune response to COVID-19 vaccine in children with IBD. METHODS: We recruited children with IBD, ages 5-17 years, who received ≥ 2 doses of the BNT162b2 vaccine by a direct-to-patient outreach and at select sites. Patient demographics, IBD characteristics, medication use, and vaccine adverse events were collected. A subset of participants had quantitative measurement of anti-receptor binding domain IgG antibodies after 2-part immunization. RESULTS: Our study population included 280 participants. Only 1 participant required an ED visit or hospitalization because of an adverse event. Of 99 participants who underwent anti-receptor binding domain IgG antibody measurement, 98 had a detectable antibody, with a mean antibody level of 43.0 µg/mL (SD 67) and a median of 22 µg/mL (interquartile range 12-38). In adjusted analyses, older age ( P = 0.028) and antitumor necrosis factor monotherapy compared with immunomodulators alone ( P = 0.005) were associated with a decreased antibody level. Antibody response in patients treated with antitumor necrosis factor combination vs monotherapy was numerically lower but not significant. DISCUSSION: Humoral immune response to COVID-19 immunization in children with IBD was robust, despite a high proportion of this pediatric cohort being treated with immunosuppressive agents. Severe vaccine-related AEs were rare. Overall, these findings provide a high level of reassurance that pediatric patients with IBD respond well and safely to SARS-CoV-2 vaccination.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Doenças Inflamatórias Intestinais , Adolescente , Adulto , Criança , Pré-Escolar , Humanos , Anticorpos , Anticorpos Antivirais , Vacina BNT162 , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Imunidade Humoral , Doenças Inflamatórias Intestinais/tratamento farmacológico , Necrose , SARS-CoV-2 , Vacinação
4.
Virol J ; 20(1): 205, 2023 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-37679808

RESUMO

Bovine viral diarrhea virus (BVDV) affects cattle worldwide causing severe productive and economic loss. In this study, we investigated the subgenotypes of BVDV circulating in cattle samples from the Aysén region, an active cattle breeding area located in southern Chile. Partial amplification of the 5' untranslated region (UTR) was performed by polymerase chain reaction (PCR), and twelve samples were analyzed by Sanger sequencing and phylogenetic analysis. Eight samples were identified as belonging to Pestivirus bovis subgenotype 1e, three to 1-b, and one to 1-d. The phylogenetic analyses performed revealed a marked distance between these now-identified strains and those previously reported in the country. These findings support the need to continually expand the analysis of the variability of the viral phylogeny for the currently circulating BVDV strains and to update the vaccines recommended for this livestock area and surrounding areas.


Assuntos
Vírus da Diarreia Viral Bovina , Animais , Bovinos , Chile/epidemiologia , Filogenia , Vírus da Diarreia Viral Bovina/genética , Regiões 5' não Traduzidas , Diarreia
5.
J Opt Soc Am A Opt Image Sci Vis ; 40(10): 1959-1968, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37855552

RESUMO

Birefringence of elliptical polarization eigenmodes can be conceptualized as a composite system comprising two distinct media: one with linear polarization eigenmodes and the other with circular polarization eigenmodes. However, the practical realization of such a system often involves the combination of two birefringent quarter-wave plates (QWPs). In this study, our objective is to characterize the variable retardation and variable elliptical polarization eigenmodes exhibited by a biplate consisting of two quarter-wave plates. Additionally, we aim to analyze the geometric properties of the transformation of one state of polarization on the Poincaré sphere, employing the emerging state's curve. This curve corresponds to the intersection between the Poincaré sphere and a cone. The outcomes of our study are presented as a function of the angle between the fast axes of the two QWPs. The findings have the potential to contribute to the configuration of q-plates and facilitate the development of quantum communication protocols.

6.
Int J Mol Sci ; 24(8)2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37108662

RESUMO

Huanglongbing (HLB) is a vascular disease of Citrus caused by three species of the α-proteobacteria "Candidatus Liberibacter", with "Candidatus Liberibacter asiaticus" (CLas) being the most widespread and the one causing significant economic losses in citrus-producing regions worldwide. However, Persian lime (Citrus latifolia Tanaka) has shown tolerance to the disease. To understand the molecular mechanisms of this tolerance, transcriptomic analysis of HLB was performed using asymptomatic and symptomatic leaves. RNA-Seq analysis revealed 652 differentially expressed genes (DEGs) in response to CLas infection, of which 457 were upregulated and 195 were downregulated. KEGG analysis revealed that after CLas infection, some DEGs were present in the plant-pathogen interaction and in the starch and sucrose metabolism pathways. DEGs present in the plant-pathogen interaction pathway suggests that tolerance against HLB in Persian lime could be mediated, at least partly, by the ClRSP2 and ClHSP90 genes. Previous reports documented that RSP2 and HSP90 showed low expression in susceptible citrus genotypes. Regarding the starch and sucrose metabolism pathways, some genes were identified as being related to the imbalance of starch accumulation. On the other hand, eight biotic stress-related genes were selected for further RT-qPCR analysis to validate our results. RT-qPCR results confirmed that symptomatic HLB leaves had high relative expression levels of the ClPR1, ClNFP, ClDR27, and ClSRK genes, whereas the ClHSL1, ClRPP13, ClPDR1, and ClNAC genes were expressed at lower levels than those from HLB asymptomatic leaves. Taken together, the present transcriptomic analysis contributes to the understanding of the CLas-Persian lime interaction in its natural environment and may set the basis for developing strategies for the integrated management of this important Citrus disease through the identification of blanks for genetic improvement.


Assuntos
Citrus , Rhizobiaceae , Citrus/genética , Citrus/microbiologia , Transcriptoma , Perfilação da Expressão Gênica , Liberibacter , Sacarose , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Rhizobiaceae/fisiologia
7.
Mol Ecol ; 30(5): 1223-1236, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33342039

RESUMO

Investigating historical gene flow in species complexes can indicate how environmental and reproductive barriers shape genome divergence during speciation. The processes influencing species diversification under environmental change remain one of the central focal points of evolutionary biology, particularly for marine organisms with high dispersal potential. We investigated genome-wide divergence, introgression patterns and inferred demographic history between species pairs of all six extant rock lobster species (Jasus spp.), which have a long larval duration of up to two years and have populated continental shelf and seamount habitats around the globe at approximately 40o S. Genetic differentiation patterns reflected geographic isolation and the environment (i.e. habitat structure). Eastern Pacific species (J. caveorum and J. frontalis) were geographically more distant and genetically more differentiated from the remaining four species. Species associated with continental shelf habitats shared a common ancestry, but are geographically distant from one another. Similarly, species associated with island/seamount habitats in the Atlantic and Indian Oceans shared a common ancestry, but are also geographically distant. Benthic temperature was the environmental variable that explained most of the genetic differentiation (FST ), while controlling for the effects of geographic distance. Eastern Pacific species retained a signal of strict isolation following ancient migration, whereas species pairs from Australia and Africa, and seamounts in the Indian and Atlantic oceans, included events of introgression after secondary contact. Our results reveal important effects of habitat and demographic processes on the recent divergence of species within the genus Jasus, providing one of the first empirical studies of genome-wide drivers of diversification that incorporates all extant species in a marine genus with long pelagic larval duration.


Assuntos
Filogenia , África , Oceano Atlântico , Austrália , Oceano Índico , Ilhas
8.
Synapse ; 75(3): e22187, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32810328

RESUMO

Diabetes is a metabolic disorder resulting in long-term hyperglycemia that could induce oxidative stress as well as neural modifications in the central nervous system. Periodontal disease is highly comorbid with diabetes and in some cases, with exacerbated pain responses. Periodontal tissue is innervated by trigeminal afferents which extend to the nucleus oralis (NO) that sends input to the ventral posterior lateral thalamic nuclei (VPL). The present study aimed to evaluate the consequences of periodontitis, diabetes and both conditions on the dendritic morphology, spine type, and density in neurons of the NO and VPL in male and female rats. A quantitative neuromorphological analysis was performed using the Cox-Golgi staining in male and female rats in four groups: naïve control, after a periodontitis procedure, diabetic, and diabetic with periodontitis. Periodontitis decreased the total dendritic length (TDL) in the NO of the male rat but no change in the female rat and no neuronal alterations were observed in the VPL of both male and female rats. In contrast, diabetes increased the number of spines in the NO and VPL and decreased TDL in the NO in both male and female rats. We observed that periodontitis induced a dimorphic effect in the NO, whereas diabetes induced a strong neuromorphological effect regardless of sex. Moreover, while periodontitis had a limited effect on the neuronal morphology, it dramatically modified the neural consequences in the VPL and NO when comorbid with diabetes. In conclusion, these neuroplastic modifications may be relevant to understand how diabetes exacerbates the outcome of periodontitis in humans, particularly in the female population.


Assuntos
Diabetes Mellitus , Periodontite , Animais , Feminino , Masculino , Plasticidade Neuronal , Neurônios/fisiologia , Ratos , Tálamo
9.
Mar Drugs ; 19(11)2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34822460

RESUMO

C-phycoerythrin (C-PE) is a phycobiliprotein that prevents oxidative stress and cell damage. The aim of this study was to evaluate whether C-PE also counteracts endoplasmic reticulum (ER) stress as a mechanism contributing to its nephroprotective activity. After C-PE was purified from Phormidium persicinum by using size exclusion chromatography, it was characterized by spectrometry and fluorometry. A mouse model of HgCl2-induced acute kidney injury (AKI) was used to assess the effect of C-PE treatment (at 25, 50, or 100 mg/kg of body weight) on oxidative stress, the redox environment, and renal damage. ER stress was examined with the same model and C-PE treatment at 100 mg/kg. C-PE diminished oxidative stress and cell damage in a dose-dependent manner by impeding the decrease in expression of nephrin and podocin normally caused by mercury intoxication. It reduced ER stress by preventing the activation of the inositol-requiring enzyme-1α (IRE1α) pathway and avoiding caspase-mediated cell death, while leaving the expression of protein kinase RNA-like ER kinase (PERK) and activating transcription factor 6α (ATF6α) pathways unmodified. Hence, C-PE exhibited a nephroprotective effect on HgCl2-induced AKI by reducing oxidative stress and ER stress.


Assuntos
Cianobactérias , Ficoeritrina/farmacologia , Substâncias Protetoras/farmacologia , Rodófitas , Injúria Renal Aguda/prevenção & controle , Animais , Organismos Aquáticos , Modelos Animais de Doenças , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Humanos , Masculino , Cloreto de Mercúrio , Camundongos , Ficoeritrina/química , Ficoeritrina/uso terapêutico , Substâncias Protetoras/química , Substâncias Protetoras/uso terapêutico
10.
Molecules ; 26(9)2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34062841

RESUMO

We synthesized twelve hybrids based on curcumin and resveratrol, and their structures were elucidated by spectroscopic analysis. The chemopreventive potential of these compounds was evaluated against SW480 human colon adenocarcinoma cells, its metastatic derivative SW620, along with the non-malignant CHO-K1 cell line. Among the tested compounds, hybrids 3e and 3i (for SW480) and 3a, 3e and 3k (for SW620) displayed the best cytotoxic activity with IC50 values ranging from 11.52 ± 2.78 to 29.33 ± 4.73 µM for both cell lines, with selectivity indices (SI) higher than 1, after 48 h of treatment. Selectivity indices were even higher than those reported for the reference drug, 5-fluorouracil (SI = 0.96), the starting compound resveratrol (SI = 0.45) and the equimolar mixture of curcumin plus resveratrol (SI = 0.77). The previous hybrids showed good antiproliferative activity.


Assuntos
Antineoplásicos/síntese química , Neoplasias Colorretais/patologia , Curcumina/farmacologia , Resveratrol/farmacologia , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Células CHO , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Cricetinae , Cricetulus , Curcumina/síntese química , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Fluoruracila/farmacologia , Humanos , Resveratrol/síntese química , Rodaminas/farmacologia
11.
Cochrane Database Syst Rev ; 8: CD012328, 2020 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-32746500

RESUMO

BACKGROUND: About half of patients with Crohn's disease (CD) require surgery within 10 years of diagnosis. Resection of the affected segment is highly effective, however the majority of patients experience clinical recurrence after surgery. Most of these patients have asymptomatic endoscopic recurrence weeks or months before starting with symptoms. This inflammation can be detected by colonoscopy and is a good predictor of poor prognosis.Therapy guided by colonoscopy could tailor the management and improve the prognosis of postoperative CD. OBJECTIVES: To assess the effects of prophylactic therapy guided by colonoscopy in reducing the postoperative recurrence of CD in adults. SEARCH METHODS: The following electronic databases were searched up to 17 December 2019: MEDLINE, Embase, CENTRAL, Clinical Trials.gov, WHO Trial Registry and Cochrane IBD specialized register. Reference lists of included articles, as well as conference proceedings were handsearched. SELECTION CRITERIA: Randomised controlled trials (RCTs), quasi-RCTs and cohort studies comparing colonoscopy-guided management versus management non-guided by colonoscopy. DATA COLLECTION AND ANALYSIS: Two review authors independently considered studies for eligibility, extracted the data and assessed study quality. Methodological quality was assessed using both the Cochrane 'Risk of bias' tool for RCTs and Newcastle-Ottawa scale (NOS) for cohort studies. The primary outcome was clinical recurrence. Secondary outcomes included: endoscopic, surgical recurrence and adverse events. We calculated the risk ratio (RR) for each dichotomous outcome and extracted the hazard ratio (HR) for time-to-event outcomes. All estimates were reported with their corresponding 95% confidence interval (CI). Data were analysed on an intention-to-treat (ITT) basis. The overall quality of the evidence was evaluated using GRADE criteria. MAIN RESULTS: Two RCTs (237 participants) and five cohort studies (794 participants) met the inclusion criteria. Meta-analysis was not conducted as the studies were highly heterogeneous. We included two comparisons. Intensification of prophylactic-therapy guided by colonoscopy versus intensification guided by clinical recurrence One unblinded RCT and four retrospective cohort studies addressed this comparison. All participants received the same prophylactic therapy immediately after surgery. In the colonoscopy-based management group the therapy was intensified in case of endoscopic recurrence; in the control group the therapy was intensified only in case of symptoms. In the RCT, clinical recurrence (defined as Crohn's Disease Activity Index (CDAI) > 150 points) in the colonoscopy-based management group was 37.7% (46/122) compared to 46.1% (21/52) in the control group at 18 months' follow up (RR 0.82, 95% CI: 0.56 to 1.18, 174 participants, low-certainty evidence). There may be a reduction in endoscopic recurrence at 18 months with colonoscopy-based management (RR 0.73, 95% CI 0.56 to 0.95, 1 RCT, 174 participants, low-certainty evidence). The certainty of the evidence for surgical recurrence was very low, due to only four cohort studies with inconsistent results reporting this outcome. Adverse events at 18 months were similar in both groups, with 82% in the intervention group (100/122) and 86.5% in the control group (45/52) (RR 0.95, 95% CI:0.83 to 1.08, 1 RCT, 174 participants, low-certainty of evidence).The most common adverse events reported were alopecia, wound infection, sensory symptoms, systemic lupus, vasculitis and severe injection site reaction. Perforations or haemorrhages secondary to colonoscopy were not reported. Initiation of prophylactic-therapy guided by colonoscopy versus initiation immediately after surgery An unblinded RCT and two retrospective cohort studies addressed this comparison. The control group received prophylactic therapy immediately after surgery, and in the colonoscopy-based management group the therapy was delayed up to detection of endoscopic recurrence. The effects on clinical and endoscopic recurrence are uncertain (clinical recurrence until week 102: RR 1.16, 95% CI 0.73 to 1.84; endoscopic recurrence at week 102: RR 1.16, 95% CI 0.73 to 1.84; 1 RCT, 63 participants, very low-certainty evidence). Results from one cohort study were similarly uncertain (median follow-up 32 months, 199 participants). The effects on surgical recurrence at a median follow-up of 50 to 55 months were also uncertain in one cohort study (RR 0.79, 95% CI 0.38 to 1.62, 133 participants, very low-certainty evidence). There were fewer adverse events with colonoscopy-based management (54.8% (17/31)) compared with the control group (93.8% (30/32)) but the evidence is very uncertain (RR 0.58, 95% CI 0.42 to 0.82; 1 RCT, 63 participants). Common adverse events were infections, gastrointestinal intolerance, leukopenia, pancreatitis and skin lesions. Perforations or haemorrhages secondary to colonoscopy were not reported. AUTHORS' CONCLUSIONS: Intensification of prophylactic-therapy guided by colonoscopy may reduce clinical and endoscopic postoperative recurrence of CD compared to intensification guided by symptoms, and there may be little or no difference in adverse effects. We are uncertain whether initiation of therapy guided by colonoscopy impacts postoperative recurrence and adverse events when compared to initiation immediately after surgery, as the certainty of the evidence is very low. Further studies are necessary to improve the certainty of the evidence of this review.


Assuntos
Colonoscopia , Doença de Crohn/prevenção & controle , Doença de Crohn/cirurgia , Prevenção Secundária/métodos , Adalimumab/efeitos adversos , Adalimumab/uso terapêutico , Adulto , Antibacterianos/uso terapêutico , Anti-Inflamatórios não Esteroides/efeitos adversos , Anti-Inflamatórios não Esteroides/uso terapêutico , Doenças Assintomáticas , Azatioprina/efeitos adversos , Azatioprina/uso terapêutico , Viés , Estudos de Coortes , Doença de Crohn/diagnóstico por imagem , Humanos , Imunossupressores/efeitos adversos , Imunossupressores/uso terapêutico , Mesalamina/efeitos adversos , Mesalamina/uso terapêutico , Metronidazol/efeitos adversos , Metronidazol/uso terapêutico , Purinas/efeitos adversos , Purinas/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Recidiva , Estudos Retrospectivos , Fator de Necrose Tumoral alfa/antagonistas & inibidores
12.
Mol Ecol ; 28(12): 3089-3100, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31055860

RESUMO

Recent studies show that soil eukaryotic diversity is immense and dominated by micro-organisms. However, it is unclear to what extent the processes that shape the distribution of diversity in plants and animals also apply to micro-organisms. Major diversification events in multicellular organisms have often been attributed to long-term climatic and geological processes, but the impact of such processes on protist diversity has received much less attention as their distribution has often been believed to be largely cosmopolitan. Here, we quantified phylogeographical patterns in Hyalosphenia papilio, a large testate amoeba restricted to Holarctic Sphagnum-dominated peatlands, to test if the current distribution of its genetic diversity can be explained by historical factors or by the current distribution of suitable habitats. Phylogenetic diversity was higher in Western North America, corresponding to the inferred geographical origin of the H. papilio complex, and was lower in Eurasia despite extensive suitable habitats. These results suggest that patterns of phylogenetic diversity and distribution can be explained by the history of Holarctic Sphagnum peatland range expansions and contractions in response to Quaternary glaciations that promoted cladogenetic range evolution, rather than the contemporary distribution of suitable habitats. Species distributions were positively correlated with climatic niche breadth, suggesting that climatic tolerance is key to dispersal ability in H. papilio. This implies that, at least for large and specialized terrestrial micro-organisms, propagule dispersal is slow enough that historical processes may contribute to their diversification and phylogeographical patterns and may partly explain their very high overall diversity.


Assuntos
Amoeba/genética , Variação Genética/genética , Filogenia , Animais , Borboletas/genética , Ecossistema , Eucariotos/genética , Especiação Genética , América do Norte , Plantas/genética , Sphagnopsida/crescimento & desenvolvimento
13.
J Hered ; 110(6): 651-661, 2019 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-31420661

RESUMO

In this study, we quantified the 3 pivotal genetic processes (i.e., genetic diversity, spatial genetic structuring, and migration) necessary for a better biological understanding and management of the singular "living-fossil" and near-threatened mouse opossum marsupial Dromiciops gliroides, the "Monito del Monte," in south-central Chile. We used 11 microsatellite loci to genotype 47 individuals distributed on the mainland and northern Chiloé Island. Allelic richness, observed and expected heterozygosity, inbreeding coefficient, and levels of genetic differentiation were estimated. The genetic structure was assessed based on Bayesian clustering methods. In addition, potential migration scenarios were evaluated based on a coalescent theory framework and Bayesian approach to parameter estimations. Microsatellites revealed moderate to high levels of genetic diversity across sampled localities. Moreover, such molecular markers suggested that at least 2 consistent genetic clusters could be identified along the D. gliroides distribution ("Northern" and "Southern" cluster). However, general levels of genetic differentiation observed among localities and between the 2 genetic clusters were relatively low. Migration analyses showed that the most likely routes of migration of D. gliroides occurred 1) from the Southern cluster to the Northern cluster and 2) from the Mainland to Chiloé Island. Our results could represent critical information for future conservation programs and for a recent proposal about the taxonomic status of this unique mouse opossum marsupial.


Assuntos
Migração Animal , Variação Genética , Genética Populacional , Marsupiais/genética , Alelos , Animais , Chile , Genótipo , Repetições de Microssatélites
15.
iScience ; 27(3): 109236, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38487019

RESUMO

HIV-associated neurological compromise is observed in more than half of all people with HIV (PWH), even under antiretroviral therapy (ART). The mechanism has been associated with the early transmigration of HIV-infected monocytes across the BBB in a CCL2 and HIV replication-dependent manner. However, the mechanisms of chronic brain damage are unknown. We demonstrate that all PWH under ART have elevated circulating ATP levels that correlate with the onset of cognitive impairment even in the absence of a circulating virus. Serum ATP levels found in PWH with the most severe neurocognitive impairment trigger the transcellular migration of HIV-infected leukocytes across the BBB in a JAM-A and LFA-1-dependent manner. We propose that targeting transcellular leukocyte transmigration could reduce or prevent the devastating consequences of HIV within the brains of PWH under ART.

16.
Biodivers Data J ; 12: e117275, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38469223

RESUMO

Background: The digital inventory of paleontological material stored in Chilean museums is highly relevant as it increases accessibility to information, both locally and over long distances, while reducing wear and tear on specimens caused by physical manipulation. The Fossil Collection database of the Museum of Zoology of the University of Concepción (UCC_MZUC_FOS) includes 144 records, with the main representatives being marine invertebrates of the Bivalvia, Echinoidea and Gastropoda classes. Notable species include Encopecalderensis, Hemiasterwayensis, Zygochlamyspatagonica and Retrotapesexalbidus, most of which come from important Chilean fossil sites. Material was collected between 1970 and 2017, with a large portion of it being donated and identified by Professor Emeritus Hugo I. Moyano and Dr. Alberto Larraín. Although the specimens contained in the resource offer basic collecting information, they substantially contribute to sharing knowledge on the fossils kept in the museums throughout the country, while providing data on their distribution. New information: This resource corresponds to the first publication of data on faunal fossils from a museum collection in Chile on the Global Biodiversity Information Facility (GBIF) platform, thereby enhancing the understanding and documentation of Chile's paleontological heritage and its national biodiversity.

17.
Biol Psychiatry Glob Open Sci ; 4(1): 155-164, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38298801

RESUMO

Background: Safety signal learning (SSL), based on conditioned inhibition of fear in the presence of learned safety, can effectively attenuate threat responses in animal models and humans. Difficulty regulating threat responses is a core feature of anxiety disorders, suggesting that SSL may provide a novel mechanism for fear reduction. Cross-species evidence suggests that SSL involves functional connectivity between the anterior hippocampus and the dorsal anterior cingulate cortex. However, the neural mechanisms supporting SSL have not been examined in relation to trait anxiety or while controlling for the effect of novelty. Methods: Here, we investigated the neural mechanisms involved in SSL and associations with trait anxiety in a sample of 64 healthy (non-clinically anxious) adults (ages 18-30 years; 43 female, 21 male) using physiological, behavioral, and neuroimaging (functional magnetic resonance imaging) data collected during an SSL task. Results: During SSL, compared with individuals with lower trait anxiety, individuals with higher trait anxiety showed less fear reduction as well as altered hippocampal activation and hippocampal-dorsal anterior cingulate cortex functional connectivity, and lower inferior frontal gyrus and ventrolateral prefrontal cortex activation. Importantly, the findings show that SSL reduces threat responding, across learning and over and above the effect of novelty, and involves hippocampal activation. Conclusions: These findings provide new insights into the nature of SSL and suggest that there may be meaningful variation in SSL and related neural correlates as a function of trait anxiety, with implications for better understanding fear reduction and optimizing interventions for individuals with anxiety disorders.

18.
Cell Rep Methods ; 4(1): 100686, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38218190

RESUMO

Precise modulation of brain activity is fundamental for the proper establishment and maturation of the cerebral cortex. To this end, cortical organoids are promising tools to study circuit formation and the underpinnings of neurodevelopmental disease. However, the ability to manipulate neuronal activity with high temporal resolution in brain organoids remains limited. To overcome this challenge, we introduce a bioelectronic approach to control cortical organoid activity with the selective delivery of ions and neurotransmitters. Using this approach, we sequentially increased and decreased neuronal activity in brain organoids with the bioelectronic delivery of potassium ions (K+) and γ-aminobutyric acid (GABA), respectively, while simultaneously monitoring network activity. This works highlights bioelectronic ion pumps as tools for high-resolution temporal control of brain organoid activity toward precise pharmacological studies that can improve our understanding of neuronal function.


Assuntos
Córtex Cerebral , Neurônios , Neurônios/fisiologia , Organoides/fisiologia , Encéfalo , Neurotransmissores
19.
PLoS One ; 19(6): e0303692, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38875291

RESUMO

Electrical signaling plays a crucial role in the cellular response to tissue injury in wound healing and an external electric field (EF) may expedite the healing process. Here, we have developed a standalone, wearable, and programmable electronic device to administer a well-controlled exogenous EF, aiming to accelerate wound healing in an in vivo mouse model to provide pre-clinical evidence. We monitored the healing process by assessing the re-epithelization rate and the ratio of M1/M2 macrophage phenotypes through histology staining. Following three days of treatment, the M1/M2 macrophage ratio decreased by 30.6% and the re-epithelization in the EF-treated wounds trended towards a non-statically significant 24.2% increase compared to the control. These findings provide point towards the effectiveness of the device in shortening the inflammatory phase by promoting reparative macrophages over inflammatory macrophages, and in speeding up re-epithelialization. Our wearable device supports the rationale for the application of programmed EFs for wound management in vivo and provides an exciting basis for further development of our technology based on the modulation of macrophages and inflammation to better wound healing.


Assuntos
Modelos Animais de Doenças , Inflamação , Macrófagos , Cicatrização , Animais , Camundongos , Inflamação/terapia , Inflamação/patologia , Masculino , Dispositivos Eletrônicos Vestíveis
20.
Cell Host Microbe ; 32(4): 606-622.e8, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38479396

RESUMO

Chikungunya virus (CHIKV) is a mosquito-borne alphavirus that causes acute, subacute, and chronic human arthritogenic diseases and, in rare instances, can lead to neurological complications and death. Here, we combined epidemiological, virological, histopathological, cytokine, molecular dynamics, metabolomic, proteomic, and genomic analyses to investigate viral and host factors that contribute to chikungunya-associated (CHIK) death. Our results indicate that CHIK deaths are associated with multi-organ infection, central nervous system damage, and elevated serum levels of pro-inflammatory cytokines and chemokines compared with survivors. The histopathologic, metabolite, and proteomic signatures of CHIK deaths reveal hemodynamic disorders and dysregulated immune responses. The CHIKV East-Central-South-African lineage infecting our study population causes both fatal and survival cases. Additionally, CHIKV infection impairs the integrity of the blood-brain barrier, as evidenced by an increase in permeability and altered tight junction protein expression. Overall, our findings improve the understanding of CHIK pathophysiology and the causes of fatal infections.


Assuntos
Febre de Chikungunya , Vírus Chikungunya , Animais , Humanos , Febre de Chikungunya/complicações , Proteômica , Vírus Chikungunya/genética , Citocinas/metabolismo
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