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1.
Cell ; 176(4): 816-830.e18, 2019 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-30595451

RESUMO

The temporal order of DNA replication (replication timing [RT]) is highly coupled with genome architecture, but cis-elements regulating either remain elusive. We created a series of CRISPR-mediated deletions and inversions of a pluripotency-associated topologically associating domain (TAD) in mouse ESCs. CTCF-associated domain boundaries were dispensable for RT. CTCF protein depletion weakened most TAD boundaries but had no effect on RT or A/B compartmentalization genome-wide. By contrast, deletion of three intra-TAD CTCF-independent 3D contact sites caused a domain-wide early-to-late RT shift, an A-to-B compartment switch, weakening of TAD architecture, and loss of transcription. The dispensability of TAD boundaries and the necessity of these "early replication control elements" (ERCEs) was validated by deletions and inversions at additional domains. Our results demonstrate that discrete cis-regulatory elements orchestrate domain-wide RT, A/B compartmentalization, TAD architecture, and transcription, revealing fundamental principles linking genome structure and function.


Assuntos
Período de Replicação do DNA/fisiologia , Replicação do DNA/genética , Replicação do DNA/fisiologia , Animais , Fator de Ligação a CCCTC/genética , Fator de Ligação a CCCTC/metabolismo , Cromatina , DNA/genética , Período de Replicação do DNA/genética , Células-Tronco Embrionárias , Elementos Facilitadores Genéticos/genética , Mamíferos/genética , Mamíferos/metabolismo , Camundongos , Proteínas Repressoras/metabolismo , Análise Espaço-Temporal
2.
Mol Cell Proteomics ; : 100809, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38936775

RESUMO

Microglia are resident immune cells of the brain and regulate its inflammatory state. In neurodegenerative diseases, microglia transition from a homeostatic state to a state referred to as disease associated microglia (DAM). DAM express higher levels of proinflammatory signaling molecules, like STAT1 and TLR2, and show transitions in mitochondrial activity toward a more glycolytic response. Inhibition of Kv1.3 decreases the proinflammatory signature of DAM, though how Kv1.3 influences the response is unknown. Our goal was to identify the potential proteins interacting with Kv1.3 during transition to DAM. We utilized TurboID, a biotin ligase, fused to Kv1.3 to evaluate potential interacting proteins with Kv1.3 via mass spectrometry in BV-2 microglia following TLR4-mediated activation. Electrophysiology, western blotting, and flow cytometry were used to evaluate Kv1.3 channel presence and TurboID biotinylation activity. We hypothesized that Kv1.3 contains domain-specific interactors that vary during a TLR4-induced inflammatory response, some of which are dependent on the PDZ-binding domain on the C-terminus. We determined that the N-terminus of Kv1.3 is responsible for trafficking Kv1.3 to the cell surface and mitochondria (e.g. NUDC, TIMM50). Whereas, the C-terminus interacts with immune signaling proteins in an LPS-induced inflammatory response (e.g. STAT1, TLR2, and C3). There are 70 proteins that rely on the C-terminal PDZ-binding domain to interact with Kv1.3 (e.g. ND3, Snx3, and Sun1). Furthermore, we used Kv1.3 blockade to verify functional coupling between Kv1.3 and interferon-mediated STAT1 activation. Overall, we highlight that the Kv1.3 potassium channel functions beyond conducting the outward flux of potassium ions in an inflammatory context and that Kv1.3 modulates the activity of key immune signaling proteins, such as STAT1 and C3.

3.
Cell Mol Life Sci ; 80(6): 140, 2023 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-37149825

RESUMO

The COVID-19 pandemic spread around the world is due to the enormous capacity of the SARS-CoV-2 coronavirus to be transmitted between humans, causing a threat to global public health. It has been shown that the entry of this virus into cells is highly facilitated by the presence of angiotensin-converting enzyme 2 (ACE2) in the cell membrane. Currently, we have no precise knowledge of how this receptor expresses in the brain of human fetus and, as a consequence, we do not know how susceptible the neural cells in the developing brain are to being infected through the vertical transmission of this virus, from mother to fetus. In this work, we describe the expression of ACE2 in the human brain at 20 weeks of gestation. This stage corresponds to the period of neuronal generation, migration, and differentiation in the cerebral cortex. We describe the specific expression of ACE2 in neuronal precursors and migratory neuroblasts of the dentate gyrus in the hippocampus. This finding implies that SARS-CoV-2 infection during the fetal period may affect neuronal progenitor cells and alter the normal development of the brain region where memory engrams are generated. Thus, although vertical transmission of SARS-CoV-2 infection was reported in few cases, the massive infection rate of young people in terms of the new variants leads to the possibility of increasing the ratio of congenital infections and originating cognitive alterations, as well as neuronal circuit anomalies that may represent vulnerability to mental problems throughout life.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Adolescente , SARS-CoV-2/metabolismo , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/metabolismo , Pandemias , Peptidil Dipeptidase A , Hipocampo/metabolismo , Giro Denteado/metabolismo
4.
J Am Pharm Assoc (2003) ; : 102056, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38401839

RESUMO

BACKGROUND: Non-medical use of psychoactive medication is a public health problem. Studies in other contexts indicate that individual sociodemographic characteristics are associated with non-medical use, but these associations have not been assessed in the Mexican context. OBJECTIVES: To estimate the prevalence non-medical and medical use of psychoactive medication among Mexican adolescents and adults' medication users and to estimate the associations between sociodemographic characteristics and non-medical use of psychoactive medication, using data from a nationally representative sample. METHODS: Secondary analysis of data collected from the National Survey of Drug, Alcohol, and Tobacco Consumption (ENCODAT) 2016 to 2017. The analytical sample included people aged 12 to 65 years. The sample was stratified into two age categories: adolescents (12-17 years) and adults (18-65 years). Sub-analyses were performed to describe prevalence of use and non-medical use of psychoactive medication at the state-level. Descriptive statistics and multinomial logistic regression models were used to estimate associations between sociodemographic characteristics and medical, non-medical, and non-use of psychoactive medication in adolescents and adults. RESULTS: Among Mexican medication users in 2016, the national prevalence of non-medical use of psychoactive drugs was 19.6%; 22.2% among adolescents and 19.4% among adults. States adjacent to the US-Mexico border reported the highest levels of non-medical use of psychoactive medication. Illicit drug consumption was associated with non-medical use. Sociodemographic characteristics associated with non-medical use varied between adolescents and adults. CONCLUSIONS: There is a high proportion of non-medical use of psychoactive drugs among Mexican medication users, especially among young people. Understanding factors associated with the misuse of psychoactive medications in Mexico can inform policy for prevention and treatment.

5.
Radiology ; 307(4): e223351, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37129492

RESUMO

Background Most low- and middle-income countries lack access to organized breast cancer screening, and women with lumps may wait months for diagnostic assessment. Purpose To demonstrate that artificial intelligence (AI) software applied to breast US images obtained with low-cost portable equipment and by minimally trained observers could accurately classify palpable breast masses for triage in a low-resource setting. Materials and Methods This prospective multicenter study evaluated participants with at least one palpable mass who were enrolled in a hospital in Jalisco, Mexico, from December 2017 through May 2021. Orthogonal US images were obtained first with portable US with and without calipers of any findings at the site of lump and adjacent tissue. Then women were imaged with standard-of-care (SOC) US with Breast Imaging Reporting and Data System assessments by a radiologist. After exclusions, 758 masses in 300 women were analyzable by AI, with outputs of benign, probably benign, suspicious, and malignant. Sensitivity, specificity, and area under the receiver operating characteristic curve (AUC) were determined. Results The mean patient age ± SD was 50.0 years ± 12.5 (range, 18-92 years) and mean largest lesion diameter was 13 mm ± 8 (range, 2-54 mm). Of 758 masses, 360 (47.5%) were palpable and 56 (7.4%) malignant, including six ductal carcinoma in situ. AI correctly identified 47 or 48 of 49 women (96%-98%) with cancer with either portable US or SOC US images, with AUCs of 0.91 and 0.95, respectively. One circumscribed invasive ductal carcinoma was classified as probably benign with SOC US, ipsilateral to a spiculated invasive ductal carcinoma. Of 251 women with benign masses, 168 (67%) imaged with SOC US were classified as benign or probably benign by AI, as were 96 of 251 masses (38%, P < .001) with portable US. AI performance with images obtained by a radiologist was significantly better than with images obtained by a minimally trained observer. Conclusion AI applied to portable US images of breast masses can accurately identify malignancies. Moderate specificity, which could triage 38%-67% of women with benign masses without tertiary referral, should further improve with AI and observer training with portable US. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Slanetz in this issue.


Assuntos
Neoplasias da Mama , Carcinoma Ductal , Feminino , Humanos , Inteligência Artificial , Triagem , Estudos Prospectivos , Ultrassonografia Mamária/métodos , Neoplasias da Mama/patologia
6.
Proc Biol Sci ; 290(2000): 20230215, 2023 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-37312552

RESUMO

The study of ecological mechanisms influencing organisms' phenotypic variation is a central subject of evolutionary biology. In this study, we characterized morphological, plumage colour and acoustic variation in cactus wrens Campylorhynchus brunneicapillus throughout its distribution. We assessed whether Gloger's, Allen's and Bergmann's ecogeographical rules, and the acoustic adaptation hypothesis relate to geographical trait variation. We analysed specimen coloration in belly and crown plumage, beak shape and structural song characteristics. We tested whether the subspecific classification or the peninsular/mainland groups mirrored the geographical variation in phenotypes and whether ecological factors were associated with patterns of trait variation. Our results suggest that colour, beak shape and acoustic traits varied across the range, in agreement with two lineages described by genetics. The simple versions of Gloger's and Allen's rules are related to variations in colour traits and morphology. Conversely, patterns of phenotypic variation did not support Bergmann's rule. The acoustic adaptation hypothesis supported song divergence for frequency-related traits. Phenotypic variation supports the hypothesis of two taxa: C. affinis in the Baja California peninsula and C. brunneicapillus in the mainland. The ecological factors are associated with phenotypic trait adaptations, suggesting that divergence between lineages could result from ecological divergence.


Assuntos
Cactaceae , Aves Canoras , Animais , Aves Canoras/genética , Cor , México , Fenótipo
7.
Mol Pharm ; 20(12): 6090-6103, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-37963105

RESUMO

Short-interfering RNA (siRNA) oligonucleotide therapeutics that modify gene expression by accessing RNA-interference (RNAi) pathways have great promise for the treatment of a range of disorders; however, their application in clinical settings has been limited by significant challenges in cellular delivery. Herein, we report a structure-function study using a series of modified cyclic amphipathic cell-penetrating peptides (CAPs) to determine the impact of peptide sequence on (1) siRNA-binding efficiency, (2) cellular delivery and knockdown efficiency, and (3) the endocytic uptake mechanism. Nine cyclic peptides of the general sequence Ac-C[XZ]4CG-NH2 in which X residues are hydrophobic/aromatic (Phe, Tyr, Trp, or Leu) and Z residues are charged/hydrophilic (Arg, Lys, Ser, or Glu) are assessed along with one acyclic peptide, Ac-(WR)4G-NH2. Cyclization is enforced by intramolecular disulfide bond formation between the flanking Cys residues. Binding analyses indicate that strong cationic character and the presence of aromatic residues that are competent to participate in CH-π interactions lead to CAP sequences that most effectively interact with siRNA. CAP-siRNA binding increases in the following order as a function of CAP hydrophobic/aromatic content: His < Phe < Tyr < Trp. Both cationic charge and disulfide-constrained cyclization of CAPs improve uptake of siRNA in vitro. Net neutral CAPs and an acyclic peptide demonstrate less-efficient siRNA translocation compared to the cyclic, cationic CAPs tested. All CAPs tested facilitated efficient siRNA target gene knockdown of at least 50% (as effective as a lipofectamine control), with the best CAPs enabling >80% knockdown. Significantly, gene knockdown efficiency does not strongly correlate with CAP-siRNA internalization efficiency but moderately correlates with CAP-siRNA-binding affinity. Finally, utilization of small-molecule inhibitors and targeted knockdown of essential endocytic pathway proteins indicate that most CAP-siRNA nanoparticles facilitate siRNA delivery through clathrin- and caveolin-mediated endocytosis. These results provide insight into the design principles for CAPs to facilitate siRNA delivery and the mechanisms by which these peptides translocate siRNA into cells. These studies also demonstrate the nature of the relationships between peptide-siRNA binding, cellular delivery of siRNA cargo, and functional gene knockdown. Strong correlations between these properties are not always observed, which illustrates the complexity in the design of optimal next-generation materials for oligonucleotide delivery.


Assuntos
Peptídeos Penetradores de Células , Peptídeos Cíclicos , Peptídeos Cíclicos/química , RNA Interferente Pequeno/química , Técnicas de Silenciamento de Genes , Peptídeos Penetradores de Células/química , Oligonucleotídeos , Dissulfetos
8.
Chromosome Res ; 30(4): 401-414, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35781769

RESUMO

The human genome is divided into functional units that replicate at specific times during S-phase. This temporal program is known as replication timing (RT) and is coordinated with the spatial organization of the genome and transcriptional activity. RT is also cell type-specific, dynamically regulated during development, and alterations in RT are observed in multiple diseases. Thus, the precise measure of RT is critical to understand the role of RT in gene function regulation. Distinct methods for assaying the RT program exist; however, conventional methods require thousands of cells as input, prohibiting its applicability to samples with limited cell numbers such as those from disease patients or from early developing embryos. Although single-cell RT analyses have been developed, these methods are low throughput, require generation of numerous libraries, increased sequencing costs, and produce low resolution data. Here, we developed an improved method to measure RT genome-wide that enables high-resolution analysis of low input samples. This method incorporates direct cell sorting into lysis buffer, as well as DNA fragmentation and library preparation in a single tube, resulting in higher yields, increased quality, and reproducibility with decreased costs. We also performed a systematic data processing analysis to provide standardized parameters for RT measurement. This optimized method facilitates RT analysis and will enable its application to a broad range of studies investigating the role of RT in gene expression, nuclear architecture, and disease.


Assuntos
Período de Replicação do DNA , Genoma Humano , Humanos , Reprodutibilidade dos Testes , Biblioteca Gênica , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Replicação do DNA
9.
Int J Geriatr Psychiatry ; 38(7): e5965, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37430439

RESUMO

OBJECTIVES: More people with dementia live in low- and middle-income countries (LMICs) than in high-income countries, but best-practice care recommendations are often based on studies from high-income countries. We aimed to map the available evidence on dementia interventions in LMICs. METHODS: We systematically mapped available evidence on interventions that aimed to improve the lives of people with dementia or mild cognitive impairment (MCI) and/or their carers in LMICs (registered on PROSPERO: CRD42018106206). We included randomised controlled trials (RCTs) published between 2008 and 2018. We searched 11 electronic academic and grey literature databases (MEDLINE, EMBASE, PsycINFO, CINAHL Plus, Global Health, World Health Organization Global Index Medicus, Virtual Health Library, Cochrane CENTRAL, Social Care Online, BASE, MODEM Toolkit) and examined the number and characteristics of RCTs according to intervention type. We used the Cochrane risk of bias 2.0 tool to assess the risk of bias. RESULTS: We included 340 RCTs with 29,882 (median, 68) participants, published 2008-2018. Over two-thirds of the studies were conducted in China (n = 237, 69.7%). Ten LMICs accounted for 95.9% of included RCTs. The largest category of interventions was Traditional Chinese Medicine (n = 149, 43.8%), followed by Western medicine pharmaceuticals (n = 109, 32.1%), supplements (n = 43, 12.6%), and structured therapeutic psychosocial interventions (n = 37, 10.9%). Overall risk of bias was judged to be high for 201 RCTs (59.1%), moderate for 136 (40.0%), and low for 3 (0.9%). CONCLUSIONS: Evidence-generation on interventions for people with dementia or MCI and/or their carers in LMICs is concentrated in just a few countries, with no RCTs reported in the vast majority of LMICs. The body of evidence is skewed towards selected interventions and overall subject to high risk of bias. There is a need for a more coordinated approach to robust evidence-generation for LMICs.


Assuntos
Disfunção Cognitiva , Demência , Humanos , China , Disfunção Cognitiva/terapia , Bases de Dados Factuais , Demência/terapia , Países em Desenvolvimento , Ensaios Clínicos Controlados Aleatórios como Assunto
10.
Salud Publica Mex ; 65(5, sept-oct): 475-484, 2023 Sep 15.
Artigo em Espanhol | MEDLINE | ID: mdl-38060918

RESUMO

OBJECTIVE: To analyze, from the perspective of intersectionality, the association of social inequality dimensions (occupation, poverty, and educational level) and socio-demographic and health characteristics with the proportion of depressive symptoms among males and females aged 50 years and older who participated in the 2001 and 2012 waves of the Mexican Health and Aging Study (MHAS). MATERIALS AND METHODS: Descriptive analysis and logistic regression models stratified by sex were performed, including interaction terms between poverty, educational level, and employment conditions on the presence of depressive symptoms. RESULTS: The proportion of females with depressive symptoms was significantly higher than that of males in both waves. A high proportion of older females in poverty, with five years or less of education and manual occupational activities, reported depressive symptoms in the MHAS-2001. The interactions evaluated between occupation, poverty, and educational level were not statistically significant under adjusted models; however, disability and comorbidities were associated with depressive symptoms in both sexes. CONCLUSION: A higher proportion of females have depressive symptoms under conditions of inequality; however, the effect of the intersection between employment and socio-demographic characteristics on depressive symptoms was not observed under adjusted models.

11.
Salud Publica Mex ; 65(1, ene-feb): 1-9, 2023 Jan 02.
Artigo em Espanhol | MEDLINE | ID: mdl-36750082

RESUMO

OBJETIVO: Estimar la prevalencia de la ideación suicida (IS) y su asociación con los determinantes sociales (DS) en la pobla-ción mexicana durante la pandemia de Covid-19. Material y métodos. Datos de la encuesta de Atención Psicológica a Distancia para la Salud Mental debido a la Contingencia por Covid-19 obtenidos durante 2020. La muestra fue de 79 665. Se realizaron modelos de regresión logística obteniendo razones de momios (RM) con intervalos de confianza del 95% (IC95%). RESULTADOS: La prevalencia de IS fue de 17.1% (mujeres:18.8% y hombres: 14.4%). Principales DS asociados fueron: ser mujer (RM=1.11; IC95% 1.06,1.13), mujeres jóvenes (RM=1.30; IC95% 1.09,1.54), escolaridad (RM=1.89; IC95% 1.14,3.12), soltera(o) (RM= 1.31; IC95% 1.24,1.38), desempleo (RM= 2.33; IC95% 2.21,2.45), distanciamiento social (RM 1.81; IC95%1.68,1.96), vivir solo (RM 1.18; IC95% 1.10,1.27), pérdida de familiar por Covid-19 (RM= 1.41; IC95%1.30,1.54), tener un diagnóstico de depresión (RM= 5.72; IC95% 5.41,6.05), ser víctima de violencia física (RM=2.71; IC95% 2.49,2.95), consumo excesivo de alcohol (RM=1.68; IC95%1.58,1.79) y drogas (RM= 3.13; IC95% 2.88,3.41), y sospecha o diagnóstico de Covid-19 (RM=1.79; IC95% 1.67,1.89). CONCLUSIONES: La prevalencia de IS durante la pandemia por Covid-19 fue elevada; se discute la relevancia de los DS estructurales e intermedios que influyen en la IS.


Assuntos
COVID-19 , Ideação Suicida , Humanos , México , Pandemias , Determinantes Sociais da Saúde , Estudos Retrospectivos
12.
Salud Publica Mex ; 65(4, jul-ago): 344-352, 2023 Jul 15.
Artigo em Espanhol | MEDLINE | ID: mdl-38060901

RESUMO

OBJETIVO: Analizar la estructura factorial, la validez convergente y divergente de la Escala Columbia de Severidad Suicida (CSSRS) y el Cuestionario de Eventos de Vida Estresantes (EVE) y medir la asociación entre EVE y conducta suicida (CS) en mujeres mexicanas durante la pandemia por Covid-19. Material y métodos. Se usaron datos de 2 398 mujeres que participaron en un estudio multicéntrico, realizado en México entre mayo y octubre de 2021. La información se recolectó mediante un cuestionario en línea que incluyó la CSSRS y el EVE. Se hizo un análisis factorial confirmatorio para valorar el ajuste de los modelos. RESULTADOS: El modelo final mostró asociación entre los EVE y la CS, y tuvo a la violencia como variable central. Dicho modelo presentó un ajuste adecuado (CFI = 0.950, IFI = 0.950, MFI = 0.975, RMSEA = 0.031, CI RMSEA = 0.026-0.036). CONCLUSIONES: La pandemia por Covid-19 evidenció la necesidad de crear e implementar estrategias que promuevan el cuidado de la salud mental, reduzcan la exposición a la violencia y faciliten los procesos de duelo para prevenir la CS en mujeres mexicanas.

13.
Commun Math Phys ; 402(2): 1167-1204, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37581014

RESUMO

The existence of a local curve of corotating and counter-rotating vortex pairs was proven by Hmidi and Mateu (in Commun Math Phys 350(2):699-747, 2017) via a desingularization of a pair of point vortices. In this paper, we construct a global continuation of these local curves. That is, we consider solutions which are more than a mere perturbation of a trivial solution. Indeed, while the local analysis relies on the study of the linear equation at the trivial solution, the global analysis requires on a deeper understanding of topological properties of the nonlinear problem. For our proof, we adapt the powerful analytic global bifurcation theorem due to Buffoni and Toland to allow for the singularity at the bifurcation point. For both the corotating and the counter-rotating pairs, along the global curve of solutions either the angular fluid velocity vanishes or the two patches self-intersect.

14.
Int J Mol Sci ; 25(1)2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38203628

RESUMO

Psittacanthus calyculatus parasitizes mesquite trees through a specialized structure called a haustorium, which, in the intrusive process, can cause cellular damage in the host tree and release DAMPs, such as ATP, sugars, RNA, and DNA. These are highly conserved molecules that primarily function as signals that trigger and activate the defense responses. In the present study, we generate extracellular DNA (exDNA) from mesquite (P. laevigata) tree leaves (self-exDNA) and P. calyculatus (non-self exDNA) mistletoe as DAMP sources to examine mesquite trees' capacity to identify specific self or non-self exDNA. We determined that mesquite trees perceive self- and non-self exDNA with the synthesis of O2•-, H2O2, flavonoids, ROS-enzymes system, MAPKs activation, spatial concentrations of JA, SA, ABA, and CKs, and auxins. Our data indicate that self and non-self exDNA application differs in oxidative burst, JA signaling, MAPK gene expression, and scavenger systems. This is the first study to examine the molecular biochemistry effects in a host tree using exDNA sources derived from a mistletoe.


Assuntos
Erva-de-Passarinho , Prosopis , Alarminas , DNA , Peróxido de Hidrogênio , Árvores
15.
Exp Appl Acarol ; 91(1): 111-121, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37468804

RESUMO

The microbiome represents a complex network among the various members of the community of microorganisms that are associated with a host. The composition of the bacterial community is essential to supplement multiple metabolic pathways that the host lacks, particularly in organisms with blood-sucking habits such as ticks. On the other hand, some endosymbionts showed some competence with potentially pathogenic microorganisms. Francisella-like endosymbionts (FLEs) encompass a group of gamma-proteobacterias that are closely related to Francisella tularensis, but are usually apathogenic, which brings nutrients like vitamin B and other cofactors to the tick. It has been postulated that the main route of transmission of FLE is vertical; however, evidence has accumulated regarding the possible mechanism of horizontal transmission. Despite growing interest in knowledge of endosymbionts in the Neotropical region, the efforts related to the establishment of their inventory for tick communities are concentrated in South and Central America, with an important gap in knowledge in Mesoamerican countries such as Mexico. For this reason, the aim of this work was to evaluate the presence and diversity of endosymbionts in the highly host-specialized tick Amblyomma nodosum collected from the anteater Tamandua mexicana in Mexico. We analysed 36 A. nodosum for the presence of DNA of endosymbiont (Coxiella and Francisella) and pathogenic (Anaplasma, Borrelia, Ehrlichia and Rickettsia) bacteria. The presence of a member of the genus Francisella and Candidatus Anaplasma brasiliensis was demonstrated. Our findings provide information on the composition of A. nodosum's microbiome, increasing the inventory of bacterial species associated with this hard tick on the American continent.


Assuntos
Amblyomma , Gammaproteobacteria , Amblyomma/microbiologia , Animais , Vermilingua/parasitologia , México , Gammaproteobacteria/classificação , Gammaproteobacteria/isolamento & purificação , Masculino , Feminino , Filogenia
16.
Rural Remote Health ; 23(3): 7695, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37666503

RESUMO

INTRODUCTION: This article analyzes risk discourses around dengue, zika and chikungunya constructed by lay people, community leaders and disease control experts from the fields of medical anthropology, medical sociology, and public health. METHODS: A qualitative ethnographic study was conducted in a municipality in Colombia (December 2016 and January 2018) with semistructured and open-ended interviews, informal dialogues, and fieldwork journal observations. RESULTS: This study found a mismatch in risk discourse about vector-borne diseases among health officials, lay people, and community leaders. These discourses are linked to the sociocultural contexts in which people live, and offer particular ways of giving meaning and acting in the face of disease prevention. CONCLUSION: The findings show a multisituated risk that refers to the inside and outside of homes; and the prevention practices mentioned by different actors, in which a continuity of tensions between lay people, leaders and government officials can be observed.


Assuntos
Aedes , Doenças Transmitidas por Vetores , Infecção por Zika virus , Zika virus , Animais , Humanos , Colômbia , Mosquitos Vetores , Saúde Pública , Infecção por Zika virus/epidemiologia , Infecção por Zika virus/prevenção & controle
17.
J Neurosci ; 41(5): 1105-1117, 2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33293358

RESUMO

A multidimensional inflammatory response ensues after status epilepticus (SE), driven partly by cyclooxygenase-2-mediated activation of prostaglandin EP2 receptors. The inflammatory response is typified by astrocytosis, microgliosis, erosion of the blood-brain barrier (BBB), formation of inflammatory cytokines, and brain infiltration of blood-borne monocytes. Our previous studies have shown that inhibition of monocyte brain invasion or systemic administration of an EP2 receptor antagonist relieves multiple deleterious consequences of SE. Here we identify those effects of EP2 antagonism that are reproduced by conditional ablation of EP2 receptors in immune myeloid cells and show that systemic EP2 antagonism blocks monocyte brain entry in male mice. The induction of hippocampal IL-6 after pilocarpine SE was nearly abolished in EP2 conditional KO mice. Serum albumin levels in the cortex, a measure of BBB breakdown, were significantly higher after SE in EP2-sufficient mice but not in EP2 conditional KOs. EP2 deficiency in innate immune cells accelerated the recovery from sickness behaviors following SE. Surprisingly, neurodegeneration was not alleviated in myeloid conditional KOs. Systemic EP2 antagonism prevented monocyte brain infiltration and provided broader rescue of SE-induced effects than myeloid EP2 ablation, including neuroprotection and broader suppression of inflammatory mediators. Reporter expression indicated that the cellular target of CD11b-driven Cre was circulating myeloid cells but, unexpectedly, not microglia. These findings indicate that activation of EP2 receptors on immune myeloid cells drives substantial deficits in behavior and disrupts the BBB after SE. The benefits of systemic EP2 antagonism can be attributed, in part, to blocking brain recruitment of blood-borne monocytes.SIGNIFICANCE STATEMENT Unabated seizures reduce quality of life, promote the development of epilepsy, and can be fatal. We previously identified activation of prostaglandin EP2 receptors as a driver of undesirable consequences of seizures. However, the relevant EP2-expressing cell types remain unclear. Here we identify peripheral innate immune cells as a driver of the EP2-related negative consequences of seizures. Removal of EP2 from peripheral immune cells was beneficial, abolishing production of a key inflammatory cytokine, accelerating weight regain, and limiting behavioral deficits. These findings provide evidence that EP2 engagement on peripheral immune and brain endothelia contributes to the deleterious effects of SE, and will assist in the development of beneficial therapies to enhance quality of life in individuals who suffer prolonged seizures.


Assuntos
Imunidade Inata/fisiologia , Células Mieloides/metabolismo , Receptores de Prostaglandina E Subtipo EP2/biossíntese , Estado Epiléptico/metabolismo , Animais , Citometria de Fluxo/métodos , Hipocampo/citologia , Hipocampo/imunologia , Hipocampo/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Células Mieloides/imunologia , Receptores de Prostaglandina E Subtipo EP2/genética , Receptores de Prostaglandina E Subtipo EP2/imunologia , Estado Epiléptico/genética , Estado Epiléptico/imunologia
18.
Toxicol Appl Pharmacol ; 454: 116242, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36108929

RESUMO

Nephrotoxicity is an important adverse effect of oxidative stress induced by hexavalent chromium [Cr(VI)]. The effect of ellagic acid, a dietary polyphenolic compound with potent antioxidant activity, was investigated in Cr(VI)-induced kidney injury. Six groups of male Wistar rats were treated intragastrically with vehicle or ellagic acid (15 and 30 mg/kg) for 10 days. On day 10, rats received saline or Cr(VI) (K2Cr2O7 15 mg/kg) subcutaneously. Cr(VI) significantly increased kidney weight, affected kidney function assessed by biomarkers in blood and urine (protein, creatinine and urea nitrogen), caused histological changes (tubular injury and glomerular capillary tuft damage), increased markers of oxidative stress and reduced the activity of antioxidant enzymes. In addition, Cr(VI) altered mitochondrial ultrastructure, impaired mitochondrial respiration, increased lipid peroxidation, and inhibited the function of mitochondrial enzymes. Pretreatment with ellagic acid (30 mg/kg) attenuated all the aforementioned alterations. Furthermore, we explored whether ellagic acid might regulate the tumor necrosis factor-alpha (TNF-α)/receptor-interacting protein kinase 3 (RIPK3) pathway, reducing Cr(VI)-induced tubular necrosis. Cr(VI) upregulated both TNF-α and RIPK3, but ellagic acid only decreased TNF-α levels, having no effect on RIPK3 content. Therefore, understanding the mechanisms through which Cr(VI) promotes necroptosis is crucial for future studies, in order to design strategies to mitigate kidney damage. In conclusion, ellagic acid attenuated Cr(VI)-induced renal alterations by preventing oxidative stress, supporting enzymatic activities, suppressing TNF-α, and preserving mitochondrial ultrastructure and function, most likely due to its antioxidant properties.


Assuntos
Antioxidantes , Fator de Necrose Tumoral alfa , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Biomarcadores/metabolismo , Cromo/metabolismo , Cromo/toxicidade , Creatinina , Ácido Elágico/metabolismo , Ácido Elágico/farmacologia , Rim , Masculino , Mitocôndrias/metabolismo , Nitrogênio/metabolismo , Estresse Oxidativo , Proteínas Quinases/metabolismo , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa/metabolismo , Ureia/metabolismo
19.
Virus Genes ; 58(6): 501-514, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36085536

RESUMO

Respiratory syncytial virus (RSV) causes lower respiratory tract infections and bronchiolitis, mainly affecting children under 2 years of age and immunocompromised patients. Currently, there are no available vaccines or efficient pharmacological treatments against RSV. In recent years, tremendous efforts have been directed to understand the pathological mechanisms of the disease and generate a vaccine against RSV. Although RSV is highly infectious, not all the patients who get infected develop bronchiolitis and severe disease. Through various sequencing studies, single nucleotide polymorphisms (SNPs) have been discovered in diverse receptors, cytokines, and transcriptional regulators with crucial role in the activation of the innate immune response, which is implicated in the susceptibility to develop or protect from severe forms of the infection. In this review, we highlighted how variations in the key genes affect the development of innate immune response against RSV. This data would provide crucial information about the mechanisms of viral infection, and in the future, could help in generation of new strategies for vaccine development or generation of the pharmacological treatments.


Assuntos
Bronquiolite , Infecções por Vírus Respiratório Sincicial , Vírus Sincicial Respiratório Humano , Criança , Humanos , Lactente , Infecções por Vírus Respiratório Sincicial/genética , Vírus Sinciciais Respiratórios , Imunidade Inata/genética , Polimorfismo de Nucleotídeo Único/genética , Vírus Sincicial Respiratório Humano/genética
20.
BMC Med Inform Decis Mak ; 22(1): 290, 2022 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-36352381

RESUMO

BACKGROUND: Epilepsy is the fourth-most common neurological disorder, affecting an estimated 50 million patients globally. Nearly 40% of patients have uncontrolled seizures yet incur 80% of the cost. Anti-epileptic drugs commonly result in resistance and reversion to uncontrolled drug-resistant epilepsy and are often associated with significant adverse effects. This has led to a trial-and-error system in which physicians spend months to years attempting to identify the optimal therapeutic approach. OBJECTIVE: To investigate the potential clinical utility from the context of optimal therapeutic prediction of characterizing cellular electrophysiology. It is well-established that genomic data alone can sometimes be predictive of effective therapeutic approach. Thus, to assess the predictive power of electrophysiological data, machine learning strategies are implemented to predict a subject's genetically defined class in an in silico model using brief electrophysiological recordings obtained from simulated neuronal networks. METHODS: A dynamic network of isogenic neurons is modeled in silico for 1-s for 228 dynamically modeled patients falling into one of three categories: healthy, general sodium channel gain of function, or inhibitory sodium channel loss of function. Data from previous studies investigating the electrophysiological and cellular properties of neurons in vitro are used to define the parameters governing said models. Ninety-two electrophysiological features defining the nature and consistency of network connectivity, activity, waveform shape, and complexity are extracted for each patient network and t-tests are used for feature selection for the following machine learning algorithms: Neural Network, Support Vector Machine, Gaussian Naïve Bayes Classifier, Decision Tree, and Gradient Boosting Decision Tree. Finally, their performance in accurately predicting which genetic category the subjects fall under is assessed. RESULTS: Several machine learning algorithms excel in using electrophysiological data from isogenic neurons to accurately predict genetic class with a Gaussian Naïve Bayes Classifier predicting healthy, gain of function, and overall, with the best accuracy, area under the curve, and F1. The Gradient Boosting Decision Tree performs the best for loss of function models indicated by the same metrics. CONCLUSIONS: It is possible for machine learning algorithms to use electrophysiological data to predict clinically valuable metrics such as optimal therapeutic approach, especially when combining several models.


Assuntos
Epilepsia , Aprendizado de Máquina , Humanos , Teorema de Bayes , Algoritmos , Máquina de Vetores de Suporte , Epilepsia/diagnóstico , Epilepsia/genética , Simulação por Computador , Neurônios , Mutação
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