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1.
Reproduction ; 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38941180

RESUMO

This study investigated the methylation patterns of H3K4me3 and H3K9me3, as well as the mRNA expression of genes encoding the epigenetic regulators KDM1AX1, KDM1AX2, and KDM3A in goat preantral follicles developed in vivo (Uncultured control) or after in vitro culture for 7 days in either the absence (α-MEM+) or presence of conditioned medium (α-MEM+ + CM) from Wharton's jelly mesenchymal stem cells (WJ-MSCs). In the in vivo setting, all follicular categories exhibited similar H3K4me3 and H3K9me3 patterns, and transcripts of KDM1AX1, KDM1AX2, and KDM3A were detected in all samples. During in vitro culture, α-MEM+ + CM enhanced several important aspects. It increased the percentage of normal growing follicles, oocyte diameters across all categories, stromal cell density, and the H3K4me3 methylation pattern in preantral follicles. Simultaneously, it decreased the levels of reduced thiols and reactive oxygen species in the spent media, diminished the presence of lipofuscin aggresomes, lowered granulosa cell apoptotic rates, and reduced the H3K9me3 methylation pattern in preantral follicles. In conclusion, the findings from this study provide compelling evidence that supplementing the in vitro culture medium (α-MEM+) with CM from WJ-MSCs has a protective effect on goat preantral follicles. Notably, CM supplementation preserved follicular survival, as evidenced by enhanced follicular and oocyte growth and increased stromal cell density when compared to the standard culture conditions in the α-MEM+ medium. Furthermore, CM reduced oxidative stress and apoptosis and promoted alterations in H3K4me3 and H3K9me3 patterns.

2.
Discov Oncol ; 15(1): 224, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38865024

RESUMO

The rapidly aging population in industrialized countries comes with an increased incidence of intrahepatic cholangiocarcinoma (iCC) which presents new challenges for oncological treatments especially in elderly patients. Thus, the question arises to what extent the benefit of surgical resections, as the only curative treatment option, outweighs possible perioperative risks in patients ≥ 80 years of age (octogenarians). We therefore retrospectively analyzed 311 patients who underwent resection for iCC at Hannover Medical School between January 1996 and December 2022. In total, there were 11 patients older than 80 years in our collective. Despite similar tumor size, octogenarians underwent comparatively less extensive surgery (54.5% major resections in octogenarians vs. 82.7% in all other patients; p = 0.033) with comparable rates of lymphadenectomy and tumor-free resection margins. Furthermore, we did not observe increased major postoperative morbidity (Clavien-Dindo ≥ IIIa complications: 27.3% vs. 34.3% in all other patients; p = 0.754) or mortality (estimated 1-year OS of 70.7% vs. 72.5% in all other patients, p = 0.099). The length of intensive care unit (ICU) or intermediate care unit (IMC) stay was significantly longer in octogenarians, however, with a comparable length in total hospital stay. The estimated overall survival (OS) did also not differ significantly, although a trend towards reduced long-term survival was observed (14.5 months vs. 28.03 months in all other patients; p = 0.099). In conclusion, primary resection is a justifiable and safe therapeutic option even in octogenarians but requires an even more thorough preoperative patient selection.

4.
Chem Asian J ; 19(11): e202400168, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38578726

RESUMO

Controlled insertion into a single P-P bond of white phosphorus (P4) was achieved by employing a diaryl stabilized stannylene, Ar*2Sn (Ar*=2,6-bis(benzhydryl)-4-iPr-phenyl). Conversions of the stannylene with P4 gave a non-pyrophoric, air-stable storage compound, which releases P4 quantitively upon irradiation with light (354 or 455 nm). Alternatively, the phosphorus cage is detached by reacting the storage compound with PhChChPh (Ch=Se, Te). Despite the recent advances in the directed conversion of P4 using main group element compounds, Ar*2Sn constitutes only the second structurally characterized example of a stannylene capable of performing controlled, reversible addition and release of white phosphorus.

5.
Nat Commun ; 15(1): 2639, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38531844

RESUMO

Asymmetry between the left and right hemisphere is a key feature of brain organization. Hemispheric functional specialization underlies some of the most advanced human-defining cognitive operations, such as articulated language, perspective taking, or rapid detection of facial cues. Yet, genetic investigations into brain asymmetry have mostly relied on common variants, which typically exert small effects on brain-related phenotypes. Here, we leverage rare genomic deletions and duplications to study how genetic alterations reverberate in human brain and behavior. We designed a pattern-learning approach to dissect the impact of eight high-effect-size copy number variations (CNVs) on brain asymmetry in a multi-site cohort of 552 CNV carriers and 290 non-carriers. Isolated multivariate brain asymmetry patterns spotlighted regions typically thought to subserve lateralized functions, including language, hearing, as well as visual, face and word recognition. Planum temporale asymmetry emerged as especially susceptible to deletions and duplications of specific gene sets. Targeted analysis of common variants through genome-wide association study (GWAS) consolidated partly diverging genetic influences on the right versus left planum temporale structure. In conclusion, our gene-brain-behavior data fusion highlights the consequences of genetically controlled brain lateralization on uniquely human cognitive capacities.


Assuntos
Variações do Número de Cópias de DNA , Estudo de Associação Genômica Ampla , Humanos , Lateralidade Funcional , Mapeamento Encefálico , Encéfalo , Imageamento por Ressonância Magnética
6.
Transl Psychiatry ; 14(1): 171, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38555309

RESUMO

There is widespread overlap across major psychiatric disorders, and this is the case at different levels of observations, from genetic variants to brain structures and function and to symptoms. However, it remains unknown to what extent these commonalities at different levels of observation map onto each other. Here, we systematically review and compare the degree of similarity between psychiatric disorders at all available levels of observation. We searched PubMed and EMBASE between January 1, 2009 and September 8, 2022. We included original studies comparing at least four of the following five diagnostic groups: Schizophrenia, Bipolar Disorder, Major Depressive Disorder, Autism Spectrum Disorder, and Attention Deficit Hyperactivity Disorder, with measures of similarities between all disorder pairs. Data extraction and synthesis were performed by two independent researchers, following the PRISMA guidelines. As main outcome measure, we assessed the Pearson correlation measuring the degree of similarity across disorders pairs between studies and biological levels of observation. We identified 2975 studies, of which 28 were eligible for analysis, featuring similarity measures based on single-nucleotide polymorphisms, gene-based analyses, gene expression, structural and functional connectivity neuroimaging measures. The majority of correlations (88.6%) across disorders between studies, within and between levels of observation, were positive. To identify a consensus ranking of similarities between disorders, we performed a principal component analysis. Its first dimension explained 51.4% (95% CI: 43.2, 65.4) of the variance in disorder similarities across studies and levels of observation. Based on levels of genetic correlation, we estimated the probability of another psychiatric diagnosis in first-degree relatives and showed that they were systematically lower than those observed in population studies. Our findings highlight that genetic and brain factors may underlie a large proportion, but not all of the diagnostic overlaps observed in the clinic.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Transtorno do Espectro Autista , Transtorno Bipolar , Transtorno Depressivo Maior , Transtornos Mentais , Esquizofrenia , Humanos , Transtorno Depressivo Maior/genética , Transtorno do Espectro Autista/genética , Transtornos Mentais/genética , Transtornos Mentais/psicologia , Transtorno Bipolar/genética , Transtorno Bipolar/epidemiologia , Esquizofrenia/genética , Esquizofrenia/epidemiologia , Transtorno do Deficit de Atenção com Hiperatividade/genética , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia
7.
Br J Anaesth ; 132(5): 1041-1048, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38448274

RESUMO

BACKGROUND: Regional anaesthesia use is growing worldwide, and there is an increasing emphasis on research in regional anaesthesia to improve patient outcomes. However, priorities for future study remain unclear. We therefore conducted an international research prioritisation exercise, setting the agenda for future investigators and funding bodies. METHODS: We invited members of specialist regional anaesthesia societies from six continents to propose research questions that they felt were unanswered. These were consolidated into representative indicative questions, and a literature review was undertaken to determine if any indicative questions were already answered by published work. Unanswered indicative questions entered a three-round modified Delphi process, whereby 29 experts in regional anaesthesia (representing all participating specialist societies) rated each indicative question for inclusion on a final high priority shortlist. If ≥75% of participants rated an indicative question as 'definitely' include in any round, it was accepted. Indicative questions rated as 'definitely' or 'probably' by <50% of participants in any round were excluded. Retained indicative questions were further ranked based on the rating score in the final Delphi round. The final research priorities were ratified by the Delphi expert group. RESULTS: There were 1318 responses from 516 people in the initial survey, from which 71 indicative questions were formed, of which 68 entered the modified Delphi process. Eleven 'highest priority' research questions were short listed, covering themes of pain management; training and assessment; clinical practice and efficacy; technology and equipment. CONCLUSIONS: We prioritised unanswered research questions in regional anaesthesia. These will inform a coordinated global research strategy for regional anaesthesia and direct investigators to address high-priority areas.


Assuntos
Anestesia por Condução , Pesquisa Biomédica , Humanos , Técnica Delphi , Inquéritos e Questionários , Projetos de Pesquisa
8.
Transl Psychiatry ; 14(1): 95, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38355713

RESUMO

Reciprocal Copy Number Variants (CNVs) at the 16p11.2 locus confer high risk for autism spectrum disorder (ASD) and other neurodevelopmental disorders (NDDs). Morphometric MRI studies have revealed large and pervasive volumetric alterations in carriers of a 16p11.2 deletion. However, the specific neuroanatomical mechanisms underlying such alterations, as well as their developmental trajectory, are still poorly understood. Here we explored differences in microstructural brain connectivity between 24 children carrying a 16p11.2 deletion and 66 typically developing (TD) children between 2 and 8 years of age. We found a large pervasive increase of intra-axonal volume widespread over a high number of white matter tracts. Such microstructural alterations in 16p11.2 deletion children were already present at an early age, and led to significant changes in the global efficiency and integration of brain networks mainly associated to language, motricity and socio-emotional behavior, although the widespread pattern made it unlikely to represent direct functional correlates. Our results shed light on the neuroanatomical basis of the previously reported increase of white matter volume, and align well with analogous evidence of altered axonal diameter and synaptic function in 16p11.2 mice models. We provide evidence of a prevalent mechanistic deviation from typical maturation of brain structural connectivity associated with a specific biological risk to develop ASD. Future work is warranted to determine how this deviation contributes to the emergence of symptoms observed in young children diagnosed with ASD and other NDDs.


Assuntos
Transtorno do Espectro Autista , Substância Branca , Criança , Humanos , Animais , Camundongos , Pré-Escolar , Deleção Cromossômica , Transtorno do Espectro Autista/diagnóstico por imagem , Transtorno do Espectro Autista/genética , Encéfalo/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Imageamento por Ressonância Magnética , Cromossomos Humanos Par 16/genética , Variações do Número de Cópias de DNA
9.
iScience ; 27(1): 108727, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38235324

RESUMO

The quiescent state is the prevalent mode of cellular life in most cells. Saccharomyces cerevisiae is a useful model for studying the molecular basis of the cell cycle, quiescence, and aging. Previous studies indicate that heterogeneous ribosomes show a specialized translation function to adjust the cellular proteome upon a specific stimulus. Using nano LC-MS/MS, we identified 69 of the 79 ribosomal proteins (RPs) that constitute the eukaryotic 80S ribosome during quiescence. Our study shows that the riboproteome is composed of 444 accessory proteins comprising cellular functions such as translation, protein folding, amino acid and glucose metabolism, cellular responses to oxidative stress, and protein degradation. Furthermore, the stoichiometry of both RPs and accessory proteins on ribosome particles is different depending on growth conditions and among monosome and polysome fractions. Deficiency of different RPs resulted in defects of translational capacity, suggesting that ribosome composition can result in changes in translational activity during quiescence.

10.
J Biol Chem ; 300(3): 105675, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38272223

RESUMO

The O-glycoprotein Mucin-2 (MUC2) forms the protective colon mucus layer. While animal models have demonstrated the importance of Muc2, few studies have explored human MUC2 in similar depth. Recent studies have revealed that secreted MUC2 is bound to human feces. We hypothesized human fecal MUC2 (HF-MUC2) was accessible for purification and downstream structural and functional characterization. We tested this via histologic and quantitative imaging on human fecal sections; extraction from feces for proteomic and O-glycomic characterization; and functional studies via growth and metabolic assays in vitro. Quantitative imaging of solid fecal sections showed a continuous mucus layer of varying thickness along human fecal sections with barrier functions intact. Lectin profiling showed HF-MUC2 bound several lectins but was weak to absent for Ulex europaeus 1 (α1,2 fucose-binding) and Sambucus nigra agglutinin (α2,6 sialic acid-binding), and did not have obvious b1/b2 barrier layers. HF-MUC2 separated by electrophoresis showed high molecular weight glycoprotein bands (∼1-2 MDa). Proteomics and Western analysis confirmed the enrichment of MUC2 and potential MUC2-associated proteins in HF-MUC2 extracts. MUC2 O-glycomics revealed diverse fucosylation, moderate sialylation, and little sulfation versus porcine colonic MUC2 and murine fecal Muc2. O-glycans were functional and supported the growth of Bacteroides thetaiotaomicron (B. theta) and short-chain fatty acid (SCFA) production in vitro. MUC2 could be similarly analyzed from inflammatory bowel disease stools, which displayed an altered glycomic profile and differential growth and SCFA production by B. theta versus healthy samples. These studies describe a new non-invasive platform for human MUC2 characterization in health and disease.


Assuntos
Colo , Fezes , Proteômica , Animais , Humanos , Camundongos , Colo/metabolismo , Glicoproteínas/metabolismo , Mucosa Intestinal/metabolismo , Mucina-2/genética , Mucina-2/metabolismo , Muco/metabolismo , Suínos , Masculino , Camundongos Endogâmicos C57BL , Microbioma Gastrointestinal
11.
Environ Microbiol ; 26(1): e16557, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38173306

RESUMO

Marine snow and other particles are abundant in estuaries, where they drive biogeochemical transformations and elemental transport. Particles range in size, thereby providing a corresponding gradient of habitats for marine microorganisms. We used standard normalized amplicon sequencing, verified with microscopy, to characterize taxon-specific microbial abundances, (cells per litre of water and per milligrams of particles), across six particle size classes, ranging from 0.2 to 500 µm, along the main stem of the Chesapeake Bay estuary. Microbial communities varied in salinity, oxygen concentrations, and particle size. Many taxonomic groups were most densely packed on large particles (in cells/mg particles), yet were primarily associated with the smallest particle size class, because small particles made up a substantially larger portion of total particle mass. However, organisms potentially involved in methanotrophy, nitrite oxidation, and sulphate reduction were found primarily on intermediately sized (5-180 µm) particles, where species richness was also highest. All abundant ostensibly free-living organisms, including SAR11 and Synecococcus, appeared on particles, albeit at lower abundance than in the free-living fraction, suggesting that aggregation processes may incorporate them into particles. Our approach opens the door to a more quantitative understanding of the microscale and macroscale biogeography of marine microorganisms.


Assuntos
Baías , Microbiota , Tamanho da Partícula , Salinidade , Oxigênio/análise , Estuários
12.
Appetite ; 193: 107129, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38008189

RESUMO

Calorie overconsumption has been proposed as a critical contributing factor to rising obesity rates. To combat this health issue, governments and policymakers have suggested implementing numerical caloric content labels. Alternatively, physical activity calorie equivalent (PACE) labels are being proposed as an easier-to-understand metric, representing the amount of physical activity required to burn off calorie content. This study examined individuals' ability to correctly estimate either the numerical caloric content or the PACE values of food images in an associative learning task. Moreover, it assessed whether this knowledge was learned and retained over time. One hundred and ninety-one participants were instructed to estimate either the numerical caloric content or PACE values of thirty food images. To facilitate learning, feedback on the correct number of calories or PACE values was provided during the first session (Time 1). To assess retention, people re-estimated numerical caloric content or PACE values of the same food pictures three days later (Time 2) and seven days later (Time 3), where feedback was not provided. Results showed that participants in both groups improved their estimations using feedback, with people being consistently more accurate when estimating numerical calorie content. Yet, our results also suggest that participants consolidated their knowledge of PACE values over time. Finally, our findings show that hunger moderates individuals' estimation ability, where hungrier people are less accurate than satiated ones. The results contribute to our understanding of how consumers process, estimate, and learn PACE labels versus numerical caloric content, and provide valuable information for researchers and policymakers to develop and implement nutritional labels as a health strategy.


Assuntos
Ingestão de Energia , Alimentos , Humanos , Aprendizagem , Preferências Alimentares , Exercício Físico , Rotulagem de Alimentos/métodos
13.
Vet Surg ; 53(2): 254-263, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37822110

RESUMO

OBJECTIVE: To compare vertebral implant placement in the canine thoracolumbar spine between 3D-printed patient-specific drill guides (3DPG) and the conventional freehand technique (FH). STUDY DESIGN: Ex vivo study. ANIMALS: Cadaveric canine spines (n = 24). METHODS: Implant trajectories were established for the left and right sides of the T10 through L6 vertebrae based on computed tomography (CT) imaging. Customized drill guides were created for each vertebra of interest. Each cadaver was randomly assigned to one of six veterinarians with varying levels of experience placing vertebral implants. Vertebrae were randomly assigned a surgical order and technique (3DPG or FH) for both sides. Postoperative CT images were acquired. A single, blinded observer assessed pin placement using a modified Zdichavsky classification. RESULTS: A total of 480 implants were placed in 240 vertebrae. Three sites were excluded from the analysis; therefore, a total of 238 implants were evaluated using the FH technique and 239 implants using 3DPG. When evaluating implant placement, 152/239 (63.6%) of 3DPG implants were considered to have an acceptable placement in comparison with 115/248 (48.32%) with FH. Overall, pin placement using 3DPG was more likely to provide acceptable pin placement (p < .001) in comparison with the FH technique for surgeons at all levels of experience. CONCLUSION: The use of 3DPG was shown to be better than the conventional freehand technique regarding acceptable placement of implants in the thoracolumbar spine of canine cadavers. CLINICAL SIGNIFICANCE: Utilizing 3DPG can be considered better than the traditional FH technique when placing implants in the canine thoracolumbar spine.


Assuntos
Doenças do Cão , Fusão Vertebral , Cirurgia Assistida por Computador , Animais , Cães , Cadáver , Doenças do Cão/cirurgia , Fusão Vertebral/instrumentação , Fusão Vertebral/métodos , Fusão Vertebral/veterinária , Cirurgia Assistida por Computador/instrumentação , Cirurgia Assistida por Computador/métodos , Cirurgia Assistida por Computador/veterinária , Tomografia Computadorizada por Raios X/veterinária , Tomografia Computadorizada por Raios X/métodos , Distribuição Aleatória , Pinos Ortopédicos
14.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1535436

RESUMO

Introducción: A consecuencia de la emergencia sanitaria por el virus SARS-CoV2, las actividades académicas migraron de forma repentina a un entorno de trabajo remoto; esto provocó que los hogares de todo el mundo se convirtieran en el asentamiento urgente de las estaciones de trabajo académico. La ergonomia como disciplina científica cobra relevancia al ser un aliado subsanador para mitigar los riesgos asociados con la aparición de lesiones musculoesqueléticas. De acuerdo con la memoria estadística del Instituto Mexicano de Seguridad Social, IMSS1, en el primer año de pandemia de COVID-19 se registraron 30 860 atenciones por lesiones en la región de manos y muñecas, 9696 en la zona de cabeza y cuello, 6251 dorsopatías y 1673 atenciones por astenopia a jóvenes de entre 18 a 29 años que desarrollaban actividades escolares. Objetivo: En este sentido, se aborda la presente investigación para conocer la composición de los espacios de trabajo académico en casa y analizar si existen factores o elementos que incidan en el riesgo de lesiones musculoesqueléticas en los estudiantes del nivel superior. Metodología: A través de un modelo de ecuaciones estructurales que cuenta con el constructo latente de las posibles lesiones (PL) en manos, espalda, piernas, cabeza, vista, oído, agotamiento físico y la respiración, las variables observables se atribuyen a los espacios utilizados para las actividades académicas en casa, muebles y equipos, Condiciones y Medio Ambiente (CyMAT). Resultados y discusión: Se encontró que un mal diseño de la estación de trabajo académico en casa, aunado a la utilización inadecuada de los muebles y equipos, aumenta la posibilidad de presentar síntomas asociados con las LMEs y, por tanto, daños en la salud del estudiante. Conclusión: La mediación de las estaciones de trabajo a través de la implementación de elementos ergonómicos mejora de forma sustancial la calidad de trabajo académico en casa, y hace evidente la importancia de la ergonomía como disciplina científica.


Introduction: As a result of the health emergency of the SARS-CoV2 virus, academic activities suddenly migrated to a remote work environment, causing homes around the world to become the urgent settlement of academic workstations. Ergonomics as a scientific discipline becomes relevant as it is a healing ally to mitigate the risks associated with the appearance of musculoskeletal injuries. According to the statistical report of the Mexican Institute of Social Security, IMSS1, in the first year of the COVID 19 pandemic, 30,860 care for injuries in the hands and wrists region, 9,696 in the head and neck area, 6,251 dorsopathies and 1,673 care for asthenopia were registered to young people between 18 and 29 years old who develop school activities. Objective: In this sense, this research is addressed to know the composition of academic workspaces at home and analyze if some factors or elements affect the risk of musculoskeletal injuries in students of the higher level. Methodology: Through a structural equations model that has the latent construct of possible injuries (PL) in the hands, back, legs, head, eyesight, hearing, physical exhaustion, and breathing; the observable variables are attributed to the spaces used for academic activities at home, furniture and equipment, conditions and environment (CyMAT) Results and discussion: It is explored that a bad design of the academic workstation at home coupled with the inappropriate use of furniture and equipment increases the possibility of presenting symptoms associated with SCI and therefore, damage to the student's health. Conclusion: The mediation of workstations through the implementation of ergonomic elements substantially improves the quality of academic work at home, making evident the importance of ergonomics as a scientific discipline

15.
Environ Microbiol ; 25(12): 3349-3363, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37861083

RESUMO

Picocyanobacteria contribute greatly to offshore primary production with cells extending through the deep euphotic zone. Literature indicates high viral infection of cyanobacteria in ocean transition zones. We postulate that the bottom of the euphotic zone is a transition zone, where communities transition from phototrophic to aphotic processes. We use single-copy core genes to examine cyanophage to cyanobacteria ratios in cellular metagenomes in the subtropical North Atlantic and Pacific. Cyanophage to cyanobacteria terL/rpoB ratios generally increase to >10 in the deep euphotic zone. As light levels decrease in the fall, Prochlorococcus in the deep euphotic zone experience reduced light levels. We find clear differences between spring (Geotraces GA02) and fall (GA03) in the North Atlantic, with terL/rpoB ratios increasing to >40 in the fall. When examining 23 months of the North Pacific Hawaii Ocean Timeseries, the depth of elevated cyanophage to cyanobacteria ratios in cellular metagenomes negatively correlated with surface photosynthetic radiation (PAR), particularly with the change in PAR, which reflected the season. In fall, all picocyanobacteria ecotypes were found at depths enriched with viruses, while in summer, only low light ecotypes were affected. Thus, we find high cyanophage infection both in the deep euphotic zone and during seasonal transitions.


Assuntos
Cianobactérias , Prochlorococcus , Estações do Ano , Água do Mar/microbiologia , Fotossíntese , Cianobactérias/genética , Oceano Pacífico , Prochlorococcus/genética
16.
J Biomech ; 160: 111826, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37826956

RESUMO

Assessing the mechanical properties of tendons in vivo allows for quantifying the degree of pathology and tracking functional improvements. The Supersonic Shearwave Imaging (SSI) technique is a state-of-the-art method for analyzing musculoskeletal tissues in vivo. This technique estimates tissue stiffness as the shear elastic modulus µ [kPa]. However, only a few studies have validated the accuracy of SSI-estimated shear modulus against the gold standard for in vitro material testing, the tensile test. This study compared the SSI-measured shear elastic modulus (µ) with the tangent modulus (Etan) obtained from mechanical tensile tests for human Achilles (AT) and patellar tendons (PT). The sample comprised eleven fresh-frozen human Achilles tendons and five fresh-frozen human patellar tendons from cadavers that were not degraded by formalin or ionizing radiation. The tendons were tested in a tensile machine, and elastography videos were collected and segmented every 5% of the total experiment time. The absolute µ values estimated from both instruments presented an up to 20-fold difference. However, a strong significant positive correlation was found between µ and Etan for both tendons (range AT: R = 0.9765-0.9972 and PT: R = 0.8719-0.9782). The two resulting curves (µ and Etan) as a function of strain (ε) were normalized by their maxima for visually comparing stiffness × strain profiles. In conclusion, despite the inaccurate absolute values, SSI has been shown to measure relative changes in human Achilles and patellar tendon stiffness. This study endorses future clinical use of SSI to provide in vivo estimations of human tendons' mechanical properties.

17.
Genes (Basel) ; 14(10)2023 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-37895241

RESUMO

Indoor residual spray (IRS), mainly employing pyrethroid insecticides, is the most common intervention for preventing malaria transmission in many regions of Latin America; the use of long-lasting insecticidal nets (LLINs) has been more limited. Knockdown resistance (kdr) is a well-characterized target-site resistance mechanism associated with pyrethroid and DDT resistance. Most mutations detected in acetylcholinesterase-1 (Ace-1) and voltage-gated sodium channel (VGSC) genes are non-synonymous, resulting in a change in amino acid, leading to the non-binding of the insecticide. In the present study, we analyzed target-site resistance in Nyssorhynchus darlingi, the primary malaria vector in the Amazon, in multiple malaria endemic localities. We screened 988 wild-caught specimens of Ny. darlingi from three localities in Amazonian Peru and four in Amazonian Brazil. Collections were conducted between 2014 and 2021. The criteria were Amazonian localities with a recent history as malaria hotspots, primary transmission by Ny. darlingi, and the use of both IRS and LLINs as interventions. Fragments of Ace-1 (456 bp) and VGSC (228 bp) were amplified, sequenced, and aligned with Ny. darlingi sequences available in GenBank. We detected only synonymous mutations in the frequently reported Ace-1 codon 280 known to confer resistance to organophosphates and carbamates, but detected three non-synonymous mutations in other regions of the gene. Similarly, no mutations linked to insecticide resistance were detected in the frequently reported codon (995) at the S6 segment of domain II of VGSC. The lack of genotypic detection of insecticide resistance mutations by sequencing the Ace-1 and VGSC genes from multiple Ny. darlingi populations in Brazil and Peru could be associated with low-intensity resistance, or possibly the main resistance mechanism is metabolic.


Assuntos
Anopheles , Inseticidas , Malária , Piretrinas , Canais de Sódio Disparados por Voltagem , Animais , Acetilcolinesterase/genética , Anopheles/genética , Resistência a Inseticidas/genética , Brasil , Peru/epidemiologia , Mosquitos Vetores/genética , Inseticidas/farmacologia , Mutação , Piretrinas/farmacologia , Canais de Sódio Disparados por Voltagem/genética , Códon
18.
Mucosal Immunol ; 16(6): 801-816, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37659724

RESUMO

Cluster of differentiation (CD4+) T cells consist of multiple subtypes, defined by expression of lineage-specific transcription factors, that contribute to the control of infectious diseases by providing help to immune and nonimmune target cells. In the current study, we examined the role of B cell lymphoma (Bcl)-6, a transcriptional repressor and master regulator of T follicular helper cell differentiation, in T cell-mediated host defense against intestinal and systemic parasitic infections. We demonstrate that while Bcl-6 expression by CD4+ T cells is critical for antibody-mediated protective immunity against secondary infection with the nematode Heligmosoides polygyrus bakeri, it paradoxically compromises worm expulsion during primary infection by limiting the generation of interleukin-10 (IL-10)-producing Gata3+ T helper 2 cells. Enhanced worm expulsion in the absence of Bcl-6 expressing T cells was associated with amplified intestinal goblet cell differentiation and increased generation of alternatively activated macrophages, effects that were reversed by neutralization of IL-10 signals. An increase in IL-10 production by Bcl-6-deficient CD4+ T cells was also evident in the context of systemic Leishmania donovani infection, but in contrast to Heligmosoides polygyrus bakeri infection, compromised T helper 1-mediated liver macrophage activation and increased susceptibility to this distinct parasitic challenge. Collectively, our studies suggest that host defense pathways that protect against parasite superinfection and lethal systemic protozoal infections can be engaged at the cost of compromised primary resistance to well-tolerated helminths.


Assuntos
Nematoides , Doenças Parasitárias , Animais , Interleucina-10 , Células Th2
19.
JAMA Netw Open ; 6(8): e2325387, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37581893

RESUMO

Importance: Postdural puncture headache (PDPH) can follow unintentional dural puncture during epidural techniques or intentional dural puncture during neuraxial procedures, such as a lumbar puncture or spinal anesthesia. Evidence-based guidance on the prevention, diagnosis, and management of this condition is, however, currently lacking. Objective: To fill the practice guidelines void and provide comprehensive information and patient-centric recommendations for preventing, diagnosing, and managing PDPH. Evidence Review: With input from committee members and stakeholders of 6 participating professional societies, 10 review questions that were deemed important for the prevention, diagnosis, and management of PDPH were developed. A literature search for each question was performed in MEDLINE on March 2, 2022. Additional relevant clinical trials, systematic reviews, and research studies published through March 2022 were also considered for practice guideline development and shared with collaborator groups. Each group submitted a structured narrative review along with recommendations that were rated according to the US Preventive Services Task Force grading of evidence. Collaborators were asked to vote anonymously on each recommendation using 2 rounds of a modified Delphi approach. Findings: After 2 rounds of electronic voting by a 21-member multidisciplinary collaborator team, 47 recommendations were generated to provide guidance on the risk factors for and the prevention, diagnosis, and management of PDPH, along with ratings for the strength and certainty of evidence. A 90% to 100% consensus was obtained for almost all recommendations. Several recommendations were rated as having moderate to low certainty. Opportunities for future research were identified. Conclusions and Relevance: Results of this consensus statement suggest that current approaches to the treatment and management of PDPH are not uniform due to the paucity of evidence. The practice guidelines, however, provide a framework for individual clinicians to assess PDPH risk, confirm the diagnosis, and adopt a systematic approach to its management.


Assuntos
Consenso , Cefaleia Pós-Punção Dural , Humanos , Cefaleia Pós-Punção Dural/diagnóstico , Cefaleia Pós-Punção Dural/prevenção & controle , Medição de Risco , Medicina Baseada em Evidências , Sociedades Médicas , Cooperação Internacional , Literatura de Revisão como Assunto
20.
Analyst ; 148(15): 3650-3658, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37424451

RESUMO

Phosphite, the anion of phosphorus acid, is an important metabolite in the global biogeochemical phosphorus cycle and a phosphorus species with unique agricultural properties. As such, methods for detecting phosphite quantitatively and selectively are critical to evidencing phosphorus redox chemistry. Here, we present a fluorescence-based assay for phosphite, utilizing the NAD+-dependent oxidation of phosphite by phosphite dehydrogenase and the subsequent reduction of resazurin to resorufin. With the application of a thermostable phosphite dehydrogenase, a medium-invariant analytical approach, and novel sample preparation methods, the assay is capable of rapid and accurate phosphite quantification with a 3 µM limit of detection in a wide array of biologically- and environmentally-relevant matrices, including bacterial and archaeal cell lysate, seawater, anaerobic digester sludge, and plant tissue. We demonstrate the utility of the assay by quantitating phosphite uptake in a model crop plant in the presence or absence of a phosphite-oxidising strain of Pseudomonas stutzeri as a soil additive, establishing this bacterium as an efficient phosphite converting biofertilizer.


Assuntos
Fosfitos , Fosfitos/metabolismo , Bactérias/metabolismo , Oxirredução , Fósforo
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