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3.
J Am Chem Soc ; 146(13): 9326-9334, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38529806

RESUMO

Recognition-encoded melamine oligomers (REMO) are synthetic polymers that feature an alternating 1,3,5-triazine-piperazine backbone and side-chains equipped with either a phenol or phosphine oxide recognition unit. An automated method for the solid-phase synthesis (SPS) of REMO of any specified sequence has been developed starting from dichlorotriazine monomer building blocks. Complementary homo-oligomers with either six phenols or six phosphine oxides were synthesized and shown to form a stable duplex in nonpolar solvents by NMR denaturation experiments. The duplex was covalently trapped by equipping the ends of the oligomers with an azide and an alkyne group and using a copper-catalyzed alkyne-azide cycloaddition (CuAAC) reaction. The SPS methodology was adapted to synthesize mixed sequence libraries by using a mixture of two different dichlorotriazine building blocks in each coupling cycle of an oligomer synthesis. The resulting libraries contain statistical mixtures of all possible sequences. The self-assembly properties of these libraries were screened by using the CuAAC reaction to trap any duplexes present. In mixed sequence libraries of 6-mers, the trapping experiments showed that only sequence-complementary oligomers formed duplexes at micromolar concentrations in dichloromethane. The automated synthesis approach developed here provides access to large libraries of mixed sequence synthetic polymers, and the covalent trapping experiment provides a convenient tool for screening functional properties of mixtures. The results suggest high-fidelity sequence-selective duplex formation in mixtures of 6-mer sequences of the REMO architecture.

4.
Mov Ecol ; 12(1): 21, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38491373

RESUMO

BACKGROUND: Ecological and physical conditions vary with depth in aquatic ecosystems, resulting in gradients of habitat suitability. Although variation in vertical distributions among individuals provides evidence of habitat selection, it has been challenging to disentangle how processes at multiple spatio-temporal scales shape behaviour. METHODS: We collected thousands of observations of depth from > 300 acoustically tagged adult Chinook salmon Oncorhynchus tshawytscha, spanning multiple seasons and years. We used these data to parameterize a machine-learning model to disentangle the influence of spatial, temporal, and dynamic oceanographic variables while accounting for differences in individual condition and maturation stage. RESULTS: The top performing machine learning model used bathymetric depth ratio (i.e., individual depth relative to seafloor depth) as a response. We found that bathymetry, season, maturation stage, and spatial location most strongly influenced Chinook salmon depth. Chinook salmon bathymetric depth ratios were deepest in shallow water, during winter, and for immature individuals. We also identified non-linear interactions among covariates, resulting in spatially-varying effects of zooplankton concentration, lunar cycle, temperature and oxygen concentration. CONCLUSIONS: Our results suggest Chinook salmon vertical habitat use is a function of ecological interactions, not physiological constraints. Temporal and spatial variation in depth distributions could be used to guide management decisions intended to reduce fishery impacts on Chinook salmon. More generally, our findings demonstrate how complex interactions among bathymetry, seasonality, location, and life history stage regulate vertical habitat selection.

5.
Life Sci Alliance ; 7(5)2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38467420

RESUMO

Kinases are key players in endothelial barrier regulation, yet their temporal function and regulatory phosphosignaling networks are incompletely understood. We developed a novel methodology, Temporally REsolved KInase Network Generation (TREKING), which combines a 28-kinase inhibitor screen with machine learning and network reconstruction to build time-resolved, functional phosphosignaling networks. We demonstrated the utility of TREKING for identifying pathways mediating barrier integrity after activation by thrombin with or without TNF preconditioning in brain endothelial cells. TREKING predicted over 100 kinases involved in barrier regulation and discerned complex condition-specific pathways. For instance, the MAPK-activated protein kinase 2 (MAPKAPK2/MK2) had early barrier-weakening activity in both inflammatory conditions but late barrier-strengthening activity exclusively with thrombin alone. Using temporal Western blotting, we confirmed that MAPKAPK2/MK2 was differentially phosphorylated under the two inflammatory conditions. We further showed with lentivirus-mediated knockdown of MAPK14/p38α and drug targeting the MAPK14/p38α-MAPKAPK2/MK2 complex that a MAP3K20/ZAK-MAPK14/p38α axis controlled the late activation of MAPKAPK2/MK2 in the thrombin-alone condition. Beyond the MAPKAPK2/MK2 switch, TREKING predicts extensive interconnected networks that control endothelial barrier dynamics.


Assuntos
Células Endoteliais , Proteína Quinase 14 Ativada por Mitógeno , Células Endoteliais/metabolismo , Trombina/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Inibidores de Proteínas Quinases
6.
Int J Mol Sci ; 25(3)2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38338692

RESUMO

The infectious agent for African trypanosomiasis, Trypanosoma brucei, possesses a unique and essential translocase of the mitochondrial inner membrane, known as the TbTIM17 complex. TbTim17 associates with six small TbTims (TbTim9, TbTim10, TbTim11, TbTim12, TbTim13, and TbTim8/13). However, the interaction patterns of these smaller TbTims with each other and TbTim17 are not clear. Through yeast two-hybrid (Y2H) and co-immunoprecipitation analyses, we demonstrate that all six small TbTims interact with each other. Stronger interactions were found among TbTim8/13, TbTim9, and TbTim10. However, TbTim10 shows weaker associations with TbTim13, which has a stronger connection with TbTim17. Each of the small TbTims also interacts strongly with the C-terminal region of TbTim17. RNAi studies indicated that among all small TbTims, TbTim13 is most crucial for maintaining the steady-state levels of the TbTIM17 complex. Further analysis of the small TbTim complexes by size exclusion chromatography revealed that each small TbTim, except for TbTim13, is present in ~70 kDa complexes, possibly existing in heterohexameric forms. In contrast, TbTim13 is primarily present in the larger complex (>800 kDa) and co-fractionates with TbTim17. Altogether, our results demonstrate that, relative to other eukaryotes, the architecture and function of the small TbTim complexes are specific to T. brucei.


Assuntos
Trypanosoma brucei brucei , Trypanosoma brucei brucei/metabolismo , Membranas Mitocondriais/metabolismo , Proteínas de Membrana Transportadoras/análise , Saccharomyces cerevisiae/metabolismo , Proteínas de Protozoários/química
7.
J Environ Manage ; 354: 120286, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38354613

RESUMO

The threat of bioterrorism has spurred research on the decontamination and containment of different agents. Anthrax [causative agent Bacillus anthracis (Ba)] is a disease that can lead to severe infections within human and animals, particularly when inhaled. This research investigated the use of spore-contaminated simulated runoff events into stormwater control measures (SCMs), which are designed to retain and improve the quality of runoff and may have the potential to filter and contain the spores. In this study, the effectiveness of a bioretention cell (BRC) and high flow media filter (HFMF) in Huron, Ohio, were evaluated for removal of Bacillus globigii (Bg) spores (a harmless cognate of Ba). Three 4-8 mm simulated runoff events were created for each SCM using a fire hydrant and Bg spores were injected into the runoff upstream of the SCM inlets. The BRC significantly (p < 0.001) outperformed the HFMF in reducing Bg concentrations and loads, with an average load reduction of 1.9 log (∼99% reduction) compared to 0.4 (∼60% reduction), respectively. A probable critical design factor leading to these differences was the infiltration rate of the media and subsequent retention time within the filters, which was supported by similar disparities in suspended solids reductions. Differences in spore removal may also have been due to particle size distribution of the HFMF, which was more gravelly than the bioretention cell. At 3 and 6 months after the-simulated runoff tests, soil samples taken from both SCMs, yielding detectable Bg spores within the top 15 cm of media, with increased spore concentrations where ponding occurred for longer durations during the tests. This suggests that forebays and areas near inlets may be hotspots for spore cleanup in a real-world bioterrorism incident.


Assuntos
Bacillus anthracis , Bacillus , Animais , Humanos , Esporos Bacterianos , Bacillus subtilis
8.
Urol Pract ; 11(2): 271-275, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38215012

RESUMO

INTRODUCTION: Following the COVID-19 pandemic, telehealth usage increased. Virtual visits minimize exposure risk while also addressing barriers to care. Telehealth offers the ability to increase patient access and provider efficiency. However, patient satisfaction with telehealth has not been fully determined. This study evaluated patient-perceived quality and satisfaction of virtual vs face-to-face visits during consultation with a dietician in the management of nephrolithiasis. METHODS: Ninety-six patients with previous diagnosis of nephrolithiasis underwent an initial, in-person nutrition consultation between May 2019 to February 2021. A follow-up with a dietician was randomized to in-person or telehealth. The telehealth group used an application called MDLive. The telehealth group used MDLive on a hospital computer during their follow-up with the urologist, whereas the in-person group had a separate appointment scheduled at a different location. Patient satisfaction following telehealth visits was assessed by the Telemedicine Satisfaction Questionnaire. Patient satisfaction following in-person visits was assessed with an 8-question modified Telemedicine Satisfaction Questionnaire, which lacked technology-related questions. RESULTS: Fifty patients were randomized to in-person follow-up and 46 to virtual follow-up. Within the virtual follow-up group more than 90% "agreed" or "strongly agreed" that they were satisfied with the quality of service provided through telemedicine. Greater than 82% reported intention to use telemedicine services again. There was no significant difference in patient satisfaction between telemedicine and face-to-face visits. Sixty-seven percent of patients in the telemedicine group reported better access to health care services and time saved and 89% reported independence accessing the telehealth system without assistance. CONCLUSIONS: This study supports the idea that telemedicine may be a successful alternative in the follow up of patients undergoing nutritional counseling for stone prevention. Future studies regarding telehealth use should evaluate which other urologic conditions are amenable to virtual management.


Assuntos
Nefrolitíase , Telemedicina , Humanos , Satisfação do Paciente , Pandemias/prevenção & controle , Aconselhamento
9.
bioRxiv ; 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38260544

RESUMO

Acetyl-coenzyme A is a central metabolite that participates in many cellular pathways. Evidence suggests that acetyl-CoA production and consumption are highly compartmentalized in mammalian cells. Yet methods to measure acetyl-CoA in living cells are lacking. In this work, we engineer an acetyl-CoA biosensor from the bacterial protein PanZ and circularly permuted green fluorescent protein (cpGFP). We biochemically characterize the sensor and demonstrate its selectivity for acetyl-CoA over other CoA species. We then deploy the biosensor in E. coli and HeLa cells to demonstrate its utility in living cells. In E. coli, we show that the biosensor enables detection of rapid changes in acetyl-CoA levels. In human cells, we show that the biosensor enables subcellular detection and reveals the compartmentalization of acetyl-CoA metabolism.

10.
Int J Pharm ; 649: 123630, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38040394

RESUMO

Viable cell density (VCD) and cell viability (CV) are key performance indicators of cell culture processes in biopharmaceutical production of biologics and vaccines. Traditional methods for monitoring VCD and CV involve offline cell counting assays that are both labor intensive and prone to high variability, resulting in sparse sampling and uncertainty in the obtained data. Process analytical technology (PAT) approaches offer a means to address these challenges. Specifically, in situ probe-based measurements of dielectric spectroscopy (also commonly known as capacitance) can characterize VCD and CV continuously in real time throughout an entire process, enabling robust process characterization. In this work, we propose in situ dielectric spectroscopy as a PAT tool for real time analysis of live-virus vaccine (LVV) production. Dielectric spectroscopy was collected across 25 discreet frequencies, offering a thorough evaluation of the proposed technology. Correlation of this PAT methodology to traditional offline cell counting assays was performed, in which VCD and CV were both successfully predicted using dielectric spectroscopy. Both univariate and multivariate data analysis approaches were evaluated for their potential to establish correlation between the in situ dielectric spectroscopy and offline measurements. Univariate analysis strategies are presented for optimal single frequency selection. Multivariate analysis, in the form of partial least squares (PLS) regression, produced significantly higher correlations between dielectric spectroscopy and offline VCD and CV data, as compared to univariate analysis. Specifically, by leveraging multivariate analysis of dielectric information from all 25 spectroscopic frequencies measured, PLS models performed significantly better than univariate models. This is particularly evident during cell death, where tracking VCD and CV have historically presented the greatest challenge. The results of this work demonstrate the potential of both single and multiple frequency dielectric spectroscopy measurements for enabling robust LVV process characterization, suggesting that broader application of in situ dielectric spectroscopy as a PAT tool in LVV processes can provide significantly improved process understanding. To the best of our knowledge, this is the first report of in situ dielectric spectroscopy with multivariate analysis to successfully predict VCD and CV in real time during live virus-based vaccine production.


Assuntos
Espectroscopia Dielétrica , Vacinas , Cricetinae , Animais , Sobrevivência Celular , Células CHO , Contagem de Células , Espectroscopia Dielétrica/métodos , Tecnologia
11.
Heart Lung ; 63: 167-174, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37925749

RESUMO

BACKGROUND: Seeing patients in an ambulatory clinic generates electronic medical record (EMR) inbox tasks. Little is known about the standard baseline message turnaround time to EMR inbox task completion and whether electronic reminders improve turnaround time. OBJECTIVE: 1) Obtain baseline message type and mean message turnaround time (MTT) to EMR inbox task completion data, 2) Standardize EMR workflow education, 3) Disseminate bi-weekly electronic reminders to fellows in their continuity clinic and measure MTT. METHODS: Prospective, non-randomized, unblinded, cross-over pre- and post-intervention pilot study in an ambulatory pulmonary clinic at a large, urban, academic referral health system. Sixteen pulmonary and critical care fellows affiliated with the Indiana University School of Medicine Pulmonary and Critical Care Fellowship were divided equally into two groups, with the study period from October of 2021 to May of 2022, and were given bi-weekly calendar reminders in Microsoft Outlook with measurement of EMR messages and MTT. RESULTS: 2554 messages were acknowledged with result notes (n = 1676, 59.16 %) being the most common. There was a 40 % decrease in overall MTT from the pre- to the post-intervention period (MTT = 33 days in pre-intervention period for whole cohort, MTT = 19 days in post-intervention period). CONCLUSIONS: MTT for EMR inbox tasks at a large, academic center with fellowship trainees is roughly 2.5 weeks. These findings should prompt other institutions to investigate their own trainees' inbox handling habits and validates the benefit of EMR training and reminders on fellowship trainee's in-basket task turnaround time.


Assuntos
Registros Eletrônicos de Saúde , Pacientes Ambulatoriais , Humanos , Projetos Piloto , Estudos Prospectivos , Fluxo de Trabalho
12.
J Asthma ; : 1-12, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38054593

RESUMO

OBJECTIVES: The purpose of this study was to examine the number of exacerbations, counts of eosinophils, and asthma-related symptoms 1 year before and after initiating benralizumab for the treatment of severe eosinophilic asthma. METHODS: Patients with prior exacerbations and newly initiating benralizumab were identified in the claims-based Healthcare Integrated Research Database. Claims were used to assess benralizumab treatment patterns, exacerbations, healthcare resource utilization, and other asthma medication used. Among a subset of patients, medical records were abstracted for Asthma Control Test (ACT) scores and asthma symptoms. RESULTS: There were 506 patients meeting inclusion/exclusion criteria for claims-based analyses and 123 for medical-record analyses. The number of patients experiencing exacerbations significantly decreased from baseline to follow-up (40% reduction, McNemar's χ2 = 204.00, p < .001). The mean number of exacerbations also decreased from 3.2 (1.5) to 1.2 (1.4) (paired t = 24.45, p < .001; Cohen's D = 1.09). The effects were larger among patients with eosinophils ≥300 cells/µL. Among patients with an ACT available for baseline and follow-up (n = 47), there was a significant reduction in the number of patients with scores <19 (72% vs. 45%, p < .01). CONCLUSIONS: Treatment with benralizumab resulted in fewer exacerbations, reduced utilization, and improved ACT scores. This study demonstrates that benralizumab is an effective treatment option for patients with severe eosinophilic asthma.

13.
Front Sports Act Living ; 5: 1210880, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38155751

RESUMO

Disuse is associated with reduced muscle oxygen saturation (SmO2). Improving oxygen delivery to tissues is important for healing, preventing muscle atrophy, and reducing the risk of deep vein thrombosis. Mobility devices are used during disuse periods to ambulate and protect the injured limb. This study examined SmO2 in walking and ambulation with various mobility devices. Thirty-eight participants randomly completed four, ten-minute trials which included: (1) walking, (2) medical kneeling scooter (MKS), (3) hands-free crutch (HFC), and (4) axillary crutch (AC). During each trial, near infrared spectroscopy sensors were placed on the vastus lateralis (VL), biceps femoris (BF), and lateral gastrocnemius (LG) of the right limb. Compared to walking, all mobility devices showed a decline in SmO2 in the VL of ∼10% (mean ± SD; 75% ± 12%-65% ± 17%, P < 0.05). In the BF, SmO2 declined ∼9% in AC compared to walking (76% ± 12%-67% ± 17%, P = 0.025). In the LG, SmO2 declined in AC (64% ± 16%) compared to MKS (70% ± 15%, P = 0.005). There were no differences in LG SmO2 compared to walking (69% ± 13%) in MKS (P > 0.05) or HFC (65% ± 15%, P > 0.05). In young, healthy volunteers, the use of mobility devices altered muscle oxygenation in several muscles. AC reduced muscle oxygenation in the VL, BF, and LG; while MKS and HFC maintained BF and LG muscle oxygenation at a level consistent with ambulatory walking.

14.
Artigo em Inglês | MEDLINE | ID: mdl-37803241

RESUMO

BACKGROUND AND OBJECTIVE: Persistent prostatic specific antigen (PSA) represents a poor prognostic factor for recurrence after radical prostatectomy (RP). However, the impact of persistent PSA on oncologic outcomes in patients undergoing salvage RP is unknown. To investigate the impact of persistent PSA after salvage RP on long-term oncologic outcomes. MATERIAL AND METHODS: Patients who underwent salvage RP for recurrent prostate cancer between 2000 and 2021 were identified from twelve high-volume centers. Only patients with available PSA after salvage RP were included. Kaplan-Meier analyses and multivariable Cox regression models were used to test the effect of persistent PSA on biochemical recurrence (BCR), metastasis and any death after salvage RP. Persistent PSA was defined as a PSA-value ≥ 0.1 ng/ml, at first PSA-measurement after salvage RP. RESULTS: Overall, 580 patients were identified. Of those, 42% (n = 242) harbored persistent PSA. Median follow-up after salvage RP was 38 months, median time to salvage RP was 64 months and median time to first PSA after salvage RP was 2.2 months. At 84 months after salvage RP, BCR-free, metastasis-free, and overall survival was 6.6 vs. 59%, 71 vs. 88% and 77 vs. 94% for patients with persistent vs. undetectable PSA after salvage RP (all p < 0.01). In multivariable Cox models persistent PSA was an independent predictor for BCR (HR: 5.47, p < 0.001) and death (HR: 3.07, p < 0.01). CONCLUSION: Persistent PSA is common after salvage RP and represents an independent predictor for worse oncologic outcomes. Patients undergoing salvage RP should be closely monitored after surgery to identify those with persistent PSA.

15.
Cell Rep ; 42(10): 113253, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37819760

RESUMO

Sequestration of Plasmodium falciparum-infected erythrocytes (IEs) in the brain microcirculation is a hallmark of cerebral malaria (CM), which leads to endothelial activation, brain swelling, and death. Here, we probed CM inflammation in a perfusable 3D human brain microvessel model. 3D brain microvessels supported in vivo-like capacities for parasite binding and maturation in situ, leading to a distinct inflammatory response from the pro-inflammatory cytokine tumor necrosis factor α (TNF-α). By combining transcriptional analysis, imaging, and leukocyte perfusion, we showed that whereas TNF-α promotes a reversible inflammatory phenotype with widespread leukocyte recruitment, parasites induce unique stress response pathways and cause localized cell adhesivity changes, focal endothelial disruptions, and apoptosis. Furthermore, parasites modified the temporal kinetics of the TNF transcriptional response, suggesting augmented inflammatory damage with the two sequential stimuli. Our findings offer mechanistic insights into CM biology in a 3D brain microvessel mimetic platform and suggest that multiple events intersect to promote brain barrier inflammation in CM.


Assuntos
Malária Cerebral , Malária Falciparum , Humanos , Fator de Necrose Tumoral alfa , Encéfalo/patologia , Plasmodium falciparum/genética , Inflamação/patologia , Microvasos/patologia , Eritrócitos/parasitologia , Malária Falciparum/parasitologia
16.
ACS Cent Sci ; 9(10): 1913-1926, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37901174

RESUMO

Biocatalysis is an established technology with significant application in the pharmaceutical industry. Immobilization of enzymes offers significant benefits for commercial and practical purposes to enhance the stability and recyclability of biocatalysts. Determination of the spatial and chemical distributions of immobilized enzymes on solid support materials is essential for an optimal catalytic performance. However, current analytical methodologies often fall short of rapidly identifying and characterizing immobilized enzyme systems. Herein, we present a new analytical methodology that combines non-negative matrix factorization (NMF)-an unsupervised machine learning tool-with Raman hyperspectral imaging to simultaneously resolve the spatial and spectral characteristics of all individual species involved in enzyme immobilization. Our novel approach facilitates the determination of the optimal NMF model using new data-driven, quantitative selection criteria that fully resolve all chemical species present, offering a robust methodology for analyzing immobilized enzymes. Specifically, we demonstrate the ability of NMF with Raman hyperspectral imaging to resolve the spatial and spectral profiles of an engineered pantothenate kinase immobilized on two different commercial microporous resins. Our results demonstrate that this approach can accurately identify and spatially resolve all species within this enzyme immobilization process. To the best of our knowledge, this is the first report of NMF within hyperspectral imaging for enzyme immobilization analysis, and as such, our methodology can now provide a new powerful tool to streamline biocatalytic process development within the pharmaceutical industry.

17.
Nat Commun ; 14(1): 6688, 2023 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-37865645

RESUMO

Femtosecond-laser-assisted material restructuring employs extreme optical intensities to localize the ablation regions. To overcome the minimum feature size limit set by the wave nature of photons, there is a need for new approaches to tailored material processing at the nanoscale. Here, we report the formation of deeply-subwavelength features in silicon, enabled by localized laser-induced phase explosions in prefabricated silicon resonators. Using short trains of mid-infrared laser pulses, we demonstrate the controllable formation of high aspect ratio (>10:1) nanotrenches as narrow as [Formula: see text]. The trench geometry is shown to be scalable with wavelength, and controlled by multiple parameters of the laser pulse train, such as the intensity and polarization of each laser pulse and their total number. Particle-in-cell simulations reveal localized heating of silicon beyond its boiling point and suggest its subsequent phase explosion on the nanoscale commensurate with the experimental data. The observed femtosecond-laser assisted nanostructuring of engineered microstructures (FLANEM) expands the nanofabrication toolbox and opens exciting opportunities for high-throughput optical methods of nanoscale structuring of solid materials.

18.
mBio ; 14(5): e0185423, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37795988

RESUMO

IMPORTANCE: Trypanosoma brucei is the unicellular parasite that causes African sleeping sickness and nagana disease in livestock. The parasite has a complex life cycle consisting of several developmental forms in the human and tsetse fly insect vector. Both the mammalian and insect hosts provide different nutritional environments, so T. brucei must adapt its metabolism to promote its survival and to complete its life cycle. As T. brucei is transmitted from the human host to the fly, the parasite must regulate its mitochondrial gene expression through a process called uridine insertion/deletion editing to achieve mRNAs capable of being translated into functional respiratory chain proteins required for energy production in the insect host. Therefore, it is essential to understand the mechanisms by which T. brucei regulates mitochondrial gene expression during transmission from the mammalian host to the insect vector.


Assuntos
Trypanosoma brucei brucei , Tripanossomíase Africana , Moscas Tsé-Tsé , Animais , Humanos , Complexo IV da Cadeia de Transporte de Elétrons/genética , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Temperatura , Moscas Tsé-Tsé/parasitologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Trypanosoma brucei brucei/metabolismo , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Mamíferos/metabolismo
19.
Am J Physiol Gastrointest Liver Physiol ; 325(6): G556-G569, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37753583

RESUMO

Parenteral nutrition (PN) prevents starvation and supports metabolic requirements intravenously when patients are unable to be fed enterally. Clinically, infants are frequently provided PN in intensive care settings along with exposure to antibiotics (ABX) to minimize infection during care. Unfortunately, neonates experience extremely high rates of hepatic complications. Adult rodent and piglet models of PN are well-established but neonatal models capable of leveraging the considerable transgenic potential of the mouse remain underdeveloped. Utilizing our newly established neonatal murine PN mouse model, we administered ABX or controlled drinking water to timed pregnant dams to disrupt the maternal microbiome. We randomized mouse pups to PN or sham surgery controls +/- ABX exposure. ABX or short-term PN decreased liver and brain organ weights, intestinal length, and mucosal architecture (vs. controls). PN significantly elevated evidence of hepatic proinflammatory markers, neutrophils and macrophage counts, bacterial colony-forming units, and evidence of cholestasis risk, which was blocked by ABX. However, ABX uniquely elevated metabolic regulatory genes resulting in accumulation of hepatocyte lipids, triglycerides, and elevated tauro-chenoxycholic acid (TCDCA) in serum. Within the gut, PN elevated the relative abundance of Akkermansia, Enterococcus, and Suterella with decreased Anaerostipes and Lactobacillus compared with controls, whereas ABX enriched Proteobacteria. We conclude that short-term PN elevates hepatic inflammatory stress and risk of cholestasis in early life. Although concurrent ABX exposure protects against hepatic immune activation during PN, the dual exposure modulates metabolism and may contribute toward early steatosis phenotype, sometimes observed in infants unable to wean from PN.NEW & NOTEWORTHY This study successfully established a translationally relevant, murine neonatal parenteral nutrition (PN) model. Short-term PN is sufficient to induce hepatitis-associated cholestasis in a neonatal murine model that can be used to understand disease in early life. The administration of antibiotics during PN protects animals from bacterial translocation and proinflammatory responses but induces unique metabolic shifts that may predispose the liver toward early steatosis.


Assuntos
Colestase , Fígado Gorduroso , Suínos , Adulto , Lactente , Feminino , Gravidez , Animais , Humanos , Camundongos , Antibacterianos/farmacologia , Modelos Animais de Doenças , Nutrição Parenteral Total , Homeostase , Animais Geneticamente Modificados
20.
RNA ; 29(12): 1881-1895, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37730435

RESUMO

Trypanosoma brucei occupies distinct niches throughout its life cycle, within both the mammalian and tsetse fly hosts. The immunological and biochemical complexity and variability of each of these environments require a reshaping of the protein landscape of the parasite both to evade surveillance and face changing metabolic demands. In kinetoplastid protozoa, including T. brucei, posttranscriptional control mechanisms are the primary means of gene regulation, and these are often mediated by RNA-binding proteins. DRBD18 is a T. brucei RNA-binding protein that reportedly interacts with ribosomal proteins and translation factors. Here, we tested a role for DRBD18 in translational control. We validate the DRBD18 interaction with translating ribosomes and the translation initiation factor, eIF3a. We further show that DRBD18 depletion by RNA interference leads to altered polysomal profiles with a specific depletion of heavy polysomes. Ribosome profiling analysis reveals that 101 transcripts change in translational efficiency (TE) upon DRBD18 depletion: 41 exhibit decreased TE and 60 exhibit increased TE. A further 66 transcripts are buffered, that is, changes in transcript abundance are compensated by changes in TE such that the total translational output is expected not to change. In DRBD18-depleted cells, a set of transcripts that codes for procyclic form-specific proteins is translationally repressed while, conversely, transcripts that code for bloodstream form- and metacyclic form-specific proteins are translationally enhanced. RNA immunoprecipitation/qRT-PCR indicates that DRBD18 associates with members of both repressed and enhanced cohorts. These data suggest that DRBD18 contributes to the maintenance of the procyclic state through both positive and negative translational control of specific mRNAs.


Assuntos
Trypanosoma brucei brucei , Animais , Trypanosoma brucei brucei/genética , Imunoprecipitação , Reação em Cadeia da Polimerase , Polirribossomos/genética , RNA , Proteínas de Protozoários/genética , Mamíferos
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