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1.
ISME Commun ; 4(1): ycae035, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38562261

RESUMO

The anaerobic cultivation of fecal microbiota is a promising approach to investigating how gut microbial communities respond to specific intestinal conditions and perturbations. Here, we describe a flexible protocol using 96-deepwell plates to cultivate stool-derived gut microbiota. Our protocol aims to address gaps in high-throughput culturing in an anaerobic chamber. We characterized the influence of the gas phase on the medium chemistry and microbial physiology and introduced a modular medium preparation process to enable the testing of several conditions simultaneously. Furthermore, we identified a medium formulation that maximized the compositional similarity of ex vivo cultures and donor microbiota while limiting the bloom of Enterobacteriaceae. Lastly, we validated the protocol by demonstrating that cultivated fecal microbiota responded similarly to dietary fibers (resistant dextrin, soluble starch) and drugs (ciprofloxacin, 5-fluorouracil) as reported in vivo. This high-throughput cultivation protocol has the potential to facilitate culture-dependent studies, accelerate the discovery of gut microbiota-diet-drug-host interactions, and pave the way to personalized microbiota-centered interventions.

2.
bioRxiv ; 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38562822

RESUMO

Single-cell genomics is a powerful tool for studying heterogeneous tissues such as the brain. Yet, little is understood about how genetic variants influence cell-level gene expression. Addressing this, we uniformly processed single-nuclei, multi-omics datasets into a resource comprising >2.8M nuclei from the prefrontal cortex across 388 individuals. For 28 cell types, we assessed population-level variation in expression and chromatin across gene families and drug targets. We identified >550K cell-type-specific regulatory elements and >1.4M single-cell expression-quantitative-trait loci, which we used to build cell-type regulatory and cell-to-cell communication networks. These networks manifest cellular changes in aging and neuropsychiatric disorders. We further constructed an integrative model accurately imputing single-cell expression and simulating perturbations; the model prioritized ~250 disease-risk genes and drug targets with associated cell types.

3.
Curr Res Neurobiol ; 6: 100128, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38577062

RESUMO

Investigating frontal EEG asymmetry as a possible biomarker of cognitive control abilities is especially important in ecological contexts such as school and work. We used a novel approach combining judgment performance and hemispheric frontal event-related potential (ERP) P300 asymmetry (fP3As) to evaluate aspects of cognitive control (i.e., repetition and switching) in adolescent females over a two-week ordinary school period. While undergoing electroencephalographic recording, students performed a word-colour "Stroop-like" congruence judgment task during morning and afternoon sessions, on Mondays and Wednesdays. Proportion of incongruence and congruence trials was 75% and 25%, respectively. ERP analysis revealed larger "novelty" right hemispheric fP3As amplitude for infrequent congruence but equivalent or significantly smaller than left hemispheric fP3As amplitude for frequent incongruence. RTs increased with extent of right fP3As shift. Behaviorally, repeat trial pairs (i.e., congruent followed by congruent, incongruent followed by incongruent) generally did not differ by time or day and were associated with near-ceiling accuracy. In contrast, switch trial pairs (i.e., congruent followed by incongruent, incongruent followed by congruent) in the afternoon were slower and associated with lower accuracy at the expected 75% criterion rate (i.e., judging incongruence by default), dropping significantly below 75% in the mornings. Crucially, compared to afternoon, morning fP3As patterns did not change adaptively with switch trial pairs. Although retroactive switching during congruence judgment was affected at all testing times, we conclude it was most impaired in the mornings of both early and mid school weeks, supporting misalignment between adolescent circadian cycle and school start time. We discuss some implications for optimal learning of adolescents at school.

5.
Hum Immunol ; : 110788, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38519405

RESUMO

The intestines have been considered the "forbidden organ" for years, and intestinal failure became the last organ failure recognized as such in the medical field. The impossibility of providing adequate nutritional support, turned these patients into recipients of just palliative comfort. In the 1960's, parenteral nutrition appeared as the most reasonable replacement therapy, but the initial success obtained with clinical kidney, heart, liver, lung and pancreas transplantation served as background to explore intestinal transplantation. The first clinical report of an isolated intestinal transplant was done by Richard Lillihei in 1967; in 1983, Thomas Starzl, performed the first multi visceral transplant, and in 1990, David Grant performed the first combined liver-intestinal transplant in an adult recipient in Canada. Since then, advances in immunosuppressive therapies and surgical innovations have allowed not only a continuous increase in indications, but also a worldwide application of all procedures, bringing clinical intestinal transplantation to reality. In this historical account, the most important contributions have been summarized, thus describing the steady progress, expansion and novelties developed over the last 56 years, since the first attempt. Clinical intestinal transplantation remains a complex and evolving field; ongoing research and technological advancements will continue shaping its future.

6.
bioRxiv ; 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38496510

RESUMO

Vibrations are ubiquitous in nature, shaping behavior across the animal kingdom. For mammals, mechanical vibrations acting on the body are detected by mechanoreceptors of the skin and deep tissues and processed by the somatosensory system, while sound waves traveling through air are captured by the cochlea and encoded in the auditory system. Here, we report that mechanical vibrations detected by the body's Pacinian corpuscle neurons, which are unique in their ability to entrain to high frequency (40-1000 Hz) environmental vibrations, are prominently encoded by neurons in the lateral cortex of the inferior colliculus (LCIC) of the midbrain. Remarkably, most LCIC neurons receive convergent Pacinian and auditory input and respond more strongly to coincident tactile-auditory stimulation than to either modality alone. Moreover, the LCIC is required for behavioral responses to high frequency mechanical vibrations. Thus, environmental vibrations captured by Pacinian corpuscles are encoded in the auditory midbrain to mediate behavior.

7.
Ann Hepatol ; 29(3): 101498, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38479458

RESUMO

The understanding of the mechanisms for the development of ascites has evolved over the years, involving the liver, peritoneum, heart, and kidneys as key responsible for its formation. In this article, we review the pathophysiology of ascites formation, introducing the role of the intestine as a major responsible for ascites production through "a game changer" case.

8.
Shock ; 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38526148

RESUMO

BACKGROUND: Critical care management of shock is a labor-intensive process. Precision automated critical care management (PACC-MAN) is an automated closed-loop system incorporating physiologic and hemodynamic inputs to deliver interventions while avoiding excessive fluid or vasopressor administration. To understand PACC-MAN efficacy, we compared PACC-MAN to provider-directed management (PDM). We hypothesized that PACC-MAN would achieve equivalent resuscitation outcomes to PDM while maintaining normotension with lower fluid and vasopressor requirements. METHODS: Twelve swine underwent 30% controlled hemorrhage over 30 minutes, followed by 45 minutes of aortic occlusion to generate a vasoplegic shock state, transfusion to euvolemia, and randomization to PACC-MAN or PDM for 4.25 hours. Primary outcomes were total crystalloid volume, vasopressor administration, total time spent at hypotension (MAP <60 mmHg), and total number of interventions. RESULTS: Weight-based fluid volumes were similar between PACC-MAN and PDM, median and IQR are reported (73.1 mL/kg [59.0-78.7] vs. 87.1 mL/kg [79.4-91.8] p = 0.07). There was no statistical difference in cumulative norepinephrine (PACC-MAN: 33.4 mcg/kg [27.1-44.6] vs. PDM: 7.5 [3.3-24.2] mcg/kg, p = 0.09). The median percentage of time spent at hypotension was equivalent (PACC-MAN: 6.2% [3.6-7.4] and PDM: 3.1% [1.3-6.6], p = 0.23). Urine outputs were similar between PACC-MAN and PDM (14.0 mL/kg vs. 21.5 mL/kg, p = 0.13). CONCLUSION: Automated resuscitation achieves equivalent resuscitation outcomes to direct human intervention in this shock model. This study provides the first translational experience with the PACC-MAN system versus PDM.

9.
Soft Matter ; 20(13): 2978-2985, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38470374

RESUMO

Nitrile rubber (i.e., NBR) is a crosslinked copolymer of butadiene and acrylonitrile that finds widespread use in the automotive and aerospace industry as it sustains large, reversible deformations while resisting swelling by petrochemical fuels. We recently demonstrated that this material has a drift in composition due to the difference in reactivity between acrylonitrile and butadiene monomers during emulsion copolymerisation. Thus, although NBR is often thought of as a random copolymer, it does experience thermodynamic driving forces for self-assembly and kinetic barriers for processing like those of block copolymers.1 Here, we illustrate how such drift in composition hinders interdiffusion and prevents self-adhesion. The key result is that contacting uncrosslinked NBR (i) in the melt, (ii) in the presence of tackifiers, or (iii) in the presence of organic solvents promotes interdiffusion and enables self-adhesion. However, the contact times required for self-adhering, tc ∼ O(100 h), are orders of magnitude above those needed for non-polar synthetic rubbers like styrene-butadiene rubber (i.e., SBR) of comparable molecular weights and glass transition temperatures, tc ∼ O(100 s), unveiling the dramatic effect of compositional inhomogeneities and physical associations on polymer interdiffusion and large-strain mechanical properties. For example, when welded with organic solvents, the self-adhesion energy of NBR continues to increase after the solvent has evaporated because of polymer nanostructuring.

10.
Chemosphere ; 355: 141760, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38537710

RESUMO

A significant and pressing issue revolves around the potential human exposure to endocrine disrupting chemicals (EDCs), which pose a substantial risk primarily through contaminated beverages. However, a comprehensive review for comparison of the migration rates of EDCs into these matrixes is currently lacking. This study reviews the beverages contamination with EDCs, including phthalates (PAEs), bisphenol A (BPA), hormone-like compounds, elements, and other organic EDCs. Also, the EDCs migration into milk and other dairy products, coffee, tea, and cold beverages related to their release from contact materials, preparation components, and storage conditions are briefly summarized. The data illustrates that besides the contamination of raw materials, the presence of EDCs associated with the type of food contact materials (FCMs)and their migration rate is increased with acidity, temperature, and storage time. The highest concentration of PAEs was detected from plastic and synthetic polymer films, while BPA strongly leaches from epoxy resins and canned metal. Furthermore, the presence of elements with endocrine disrupting characteristics was confirmed in cold beverages, soft drinks, hot drink and milk. Moreover, hormone-like compounds have been found to be released from coffee preparation components. Despite the few data about the migration rate of other EDCs including UV-stabilizers, surfactants, and antibacterial compounds into beverages, their presence was reported into milk, coffee, and different beverages, especially in packed samples. Studies on the EDCs leaching have primarily focused on PAEs and BPA, while other compounds require further investigation. Regardless, the possible risk that EDCs pose to humans through beverage consumption cannot be overlooked.


Assuntos
Café , Disruptores Endócrinos , Humanos , Animais , Disruptores Endócrinos/análise , Bebidas/análise , Leite/química , Hormônios , Compostos Benzidrílicos/análise
11.
Proc Natl Acad Sci U S A ; 121(9): e2316469121, 2024 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-38354254

RESUMO

Diversity-generating retroelements (DGRs) are used by bacteria, archaea, and viruses as a targeted mutagenesis tool. Through error-prone reverse transcription, DGRs introduce random mutations at specific genomic loci, enabling rapid evolution of these targeted genes. However, the function and benefits of DGR-diversified proteins in cellular hosts remain elusive. We find that 82% of DGRs from one of the major monophyletic lineages of DGR reverse transcriptases are encoded by multicellular bacteria, which often have two or more DGR loci in their genomes. Using the multicellular purple sulfur bacterium Thiohalocapsa sp. PB-PSB1 as an example, we characterized nine distinct DGR loci capable of generating 10282 different combinations of target proteins. With environmental metagenomes from individual Thiohalocapsa aggregates, we show that most of PB-PSB1's DGR target genes are diversified across its biogeographic range, with spatial heterogeneity in the diversity of each locus. In Thiohalocapsa PB-PSB1 and other bacteria hosting this lineage of cellular DGRs, the diversified target genes are associated with NACHT-domain anti-phage defenses and putative ternary conflict systems previously shown to be enriched in multicellular bacteria. We propose that these DGR-diversified targets act as antigen sensors that confer a form of adaptive immunity to their multicellular consortia, though this remains to be experimentally tested. These findings could have implications for understanding the evolution of multicellularity, as the NACHT-domain anti-phage systems and ternary systems share both domain homology and conceptual similarities with the innate immune and programmed cell death pathways of plants and metazoans.


Assuntos
Bactérias , Bacteriófagos , Bactérias/genética , Archaea/genética , Metagenoma , Retroelementos , Bacteriófagos/genética
12.
J Hazard Mater ; 468: 133839, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38402681

RESUMO

The contamination of coastal ecosystems by personal protective equipment (PPE) emerged as a significant concern immediately following the declaration of the COVID-19 pandemic by the World Health Organization (WHO). Hence, numerous studies have assessed PPE occurrence on beaches worldwide. However, no predictors on PPE contamination was so far pointed out. The present study investigated social and landscape drivers affecting the PPE density in coastal environments worldwide using a meta-analysis approach. Spatial variables such as urban modification levels, coastal vegetation coverage, population density (HPD), distance from rivers (DNR), and poverty degree (GGRDI) were derived from global satellite data. These variables, along with the time elapsed after WHO declared the pandemic, were included in generalized additive models as potential predictors of PPE density. HPD consistently emerged as the most influential predictor of PPE density (p < 0.00001), exhibiting a positive effect. Despite the presence of complex non-linear relationships, our findings indicate higher PPE density in areas with intermediate GGRDI levels, indicative of emerging economies. Additionally, elevated PPE density was observed in areas located further away from rivers (p < 0.001), and after the initial months of the pandemic. Despite the uncertainties associated with the varied sampling methods employed by the studies comprising our database, this study offers a solid baseline for tackling the global problem of PPE contamination on beachesguiding monitoring assessments in future pandemics.


Assuntos
COVID-19 , Pandemias , Humanos , Pandemias/prevenção & controle , Ecossistema , Transmissão de Doença Infecciosa do Paciente para o Profissional , Pessoal de Saúde , COVID-19/epidemiologia , COVID-19/prevenção & controle , Equipamento de Proteção Individual
13.
Environ Sci Pollut Res Int ; 31(14): 22145-22157, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38403824

RESUMO

Plastic contamination is widely recognized as a major environmental concern due to the entry of small plastic particles into the food chain, thereby posing potential hazards to human health. However, the current understanding of microplastic (MP; < 5 mm) particles in livestock, which serve as an important food source, is limited. This study aims to investigate the concentration and characteristics of MPs in edible tissues of cow and sheep, namely liver, meat, and tripe, obtained from butcher shops in five areas of Bushehr port, Iran. The mean concentration of MPs in different tissues of cow and sheep were 0.14 and 0.13 items/g, respectively. Among the examined tissues, cow meat exhibited the highest concentration of MPs, with a concentration of 0.19 items/g. Nylon and fiber were identified as the predominant polymer types and shapes of MPs found in cow and sheep tissues, respectively. Furthermore, no statistically significant difference was observed in MP concentration across different tissues of cow and sheep. Significantly, this study highlights the elevated hazards associated with exposure to MPs through the consumption of edible cow and sheep tissues, particularly for children who consume meat. The results underscore the potential transfer of MPs from the environment to livestock bodies through their food, contamination during meat processing, and subsequent health hazards for consumers.


Assuntos
Microplásticos , Plásticos , Criança , Animais , Bovinos , Ovinos , Humanos , Gado , Carne , Fígado
14.
Biomimetics (Basel) ; 9(2)2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38392156

RESUMO

Loss of an upper limb exerts a negative influence on an individual's ability to perform their activities of daily living (ADLs), reducing quality of life and self-esteem. A prosthesis capable of performing basic ADLs functions has the capability of restoring independence and autonomy to amputees. However, current technologies present in robotic prostheses are based on rigid actuators with several drawbacks, such as high weight and low compliance. Recent advances in robotics have allowed for the development of flexible actuators and artificial muscles to overcome the limitations of rigid actuators. Dielectric elastomer actuators (DEAs) consist of a thin elastomer membrane arranged between two compliant electrodes capable of changing dimensions when stimulated with an electrical potential difference. In this work, we present the design and testing of a finger prosthesis driven by two DEAs arranged as agonist-antagonist pairs as artificial muscles. The soft actuators are designed as fiber-constrained dielectric elastomers (FCDE), enabling displacement in just one direction as natural muscles. The finger prosthesis was designed and modeled to show bend movement using just one pair of DEAs and was made of PLA in an FDM 3D printer to be lightweight. The experimental results show great agreement with the proposed model and indicate that the proposed finger prosthesis is promising in overcoming the limitations of the current rigid based actuators.

15.
Mol Microbiol ; 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38323722

RESUMO

The diarrheal disease cholera is caused by the versatile and responsive bacterium Vibrio cholerae, which is capable of adapting to environmental changes. Among others, the alternative sigma factor RpoS activates response pathways, including regulation of motility- and chemotaxis-related genes under nutrient-poor conditions in V. cholerae. Although RpoS has been well characterised, links between RpoS and other regulatory networks remain unclear. In this study, we identified the ArcAB two-component system to control rpoS transcription and RpoS protein stability in V. cholerae. In a manner similar to that seen in Escherichia coli, the ArcB kinase not only activates the response regulator ArcA but also RssB, the anti-sigma factor of RpoS. Our results demonstrated that, in V. cholerae, RssB is phosphorylated by ArcB, which subsequently activates RpoS proteolysis. Furthermore, ArcA acts as a repressor of rpoS transcription. Additionally, we determined that the cysteine residue at position 180 of ArcB is crucial for signal recognition and activity. Thus, our findings provide evidence linking RpoS response to the anoxic redox control system ArcAB in V. cholerae.

17.
Am Surg ; : 31348241227198, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38215041

RESUMO

Laparoscopic common bile duct exploration (LCBDE) utility in management of choledocholithiasis may decrease length of stay and patient cost, but postoperative management remains widely debated. We examined periprocedural LFTs for patients undergoing LCBDE and endoscopic retrograde cholangiopancreatography (ERCP) speculating for trend existence after successful LCBDE. We hypothesized that postoperative LCBDE LFTs would not downtrend even after successful ductal clearance. We identified 99 patients under 18 who underwent ERCP or LCBDE with at least one pre- and post-procedural LFT. Periprocedural LFTs between groups were compared using Wilcoxon signed-rank tests. The 22 ERCP patients demonstrated a significant downtrend across Tbili (P < .001), AST (P = .001), ALT (P = .002), and ALP (P < .001). The 27 LCBDE patients demonstrated a significant downtrend in Tbili (P = .002) only, while AST (P > .05), ALT (P > .05), and ALP (P > .05) were nonsignificant. Lack of consistent downtrend in the LCBDE group raises doubt regarding the utility of postoperative LFTs for post-procedural management.

18.
J Anat ; 244(3): 537-539, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38063239

RESUMO

Boyde et al. (2023) stated that Moura et al. (2021) did not explain how fleas generated cavities in armadillo osteoderms, which is wrongly stated, also presenting a misrepresentation of what is written about this in Moura et al. (2021).


Assuntos
Tatus , Sifonápteros , Animais
19.
J Pediatr Surg ; 59(3): 389-392, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37957103

RESUMO

BACKGROUND: Patients with choledocholithiasis are often treated with endoscopic retrograde cholangiopancreatography (ERCP) followed by laparoscopic cholecystectomy (LC). Upfront LC, intraoperative cholangiogram (IOC), and possible transcystic laparoscopic common bile duct exploration (LCBDE) could potentially avoid the need for ERCP. We hypothesized that upfront LC + IOC ± LCBDE will decrease length of stay (LOS) and the total number of interventions for children with suspected choledocholithiasis. METHODS: A multicenter, retrospective cohort study was performed on pediatric patients (<18 years) between 2018 and 2022 with suspected choledocholithiasis. Demographic and clinical data were compared for upfront LC + IOC ± LCBDE and possible postoperative ERCP (OR1st) versus preoperative ERCP prior to LC (OR2nd). Complications were defined as postoperative pancreatitis, recurrent choledocholithiasis, bleeding, or abscess. RESULTS: Across four centers, 252 children with suspected choledocholithiasis were treated with OR1st (n = 156) or OR2nd (n = 96). There were no differences in age, gender, or body mass index. Of the LCBDE patients (72/156), 86% had definitive intraoperative management with the remaining 14% requiring postoperative ERCP. Complications were fewer and LOS was shorter with OR1st (3/156 vs. 15/96; 2.39 vs 3.84 days, p < 0.05). CONCLUSION: Upfront LC + IOC ± LCBDE for children with choledocholithiasis is associated with fewer ERCPs, lower LOS, and decreased complications. Postoperative ERCP remains an essential adjunct for patients who fail LCBDE. Further educational efforts are needed to increase the skill level for IOC and LCBDE in pediatric patients with suspected choledocholithiasis. LEVEL OF EVIDENCE: Level III.


Assuntos
Colecistectomia Laparoscópica , Coledocolitíase , Humanos , Criança , Coledocolitíase/cirurgia , Estudos Retrospectivos , Colangiopancreatografia Retrógrada Endoscópica , Tempo de Internação , Ducto Colédoco/cirurgia
20.
Mar Pollut Bull ; 198: 115825, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38029669

RESUMO

Transport of ballast water is considered a significant vector for dispersion of different pollutants, including microplastics (MPs), throughout the world's oceans. However, there is limited information on MPs in ballast water. Size distribution, polymer type, and ecological risks of MPs in ballast water were investigated for the first time in this study. The mean levels of MPs in ballast water and seawater samples were 12.53 and 11.80 items/L, respectively. MPs with a size category of 50-300 µm was the most abundant. Fiber, black, and polycarbonate (PC) were the predominant shape, color, and polymer type of identified MPs in ballast water and seawater, respectively. The pollution load index (PLI), hazard index (HI), and risk quotient (RQ) indicated high levels of MP pollution, potentially indicating an ecological risk. These findings increase our understanding of the major sources (such as ballast water), transportation routes, and related ecological risks of MPs to marine ecosystems.


Assuntos
Microplásticos , Poluentes Químicos da Água , Microplásticos/análise , Plásticos/análise , Água/análise , Ecossistema , Oceano Índico , Navios , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Polímeros/análise , Medição de Risco
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