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1.
J Biomech ; 170: 112160, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38824704

RESUMO

A single depth camera provides a fast and easy approach to performing biomechanical assessments in a clinical setting; however, there are currently no established methods to reliably determine joint angles from these devices. The primary aim of this study was to compare joint angles as well as the between-day reliability of direct kinematics to model-constrained inverse kinematics recorded using a single markerless depth camera during a range of clinical and athletic movement assessments.A secondary aim was to determine the minimum number of trials required to maximize reliability. Eighteen healthy participants attended two testing sessions one week apart. Tasks included treadmill walking, treadmill running, single-leg squats, single-leg countermovement jumps, bilateral countermovement jumps, and drop vertical jumps. Keypoint data were processed using direct kinematics as well as in OpenSim using a full-body musculoskeletal model and inverse kinematics. Kinematic methods were compared using statistical parametric mapping and between-day reliability was calculated using intraclass correlation coefficients, mean absolute error, and minimal detectable change. Keypoint-derived inverse kinematics resulted in significantly smaller hip flexion (range = -9 to -2°), hip abduction (range = -3 to -2°), knee flexion (range = -5° to -2°), and greater dorsiflexion angles (range = 6-15°) than direct kinematics. Both markerless kinematic methods had high between-day reliability (inverse kinematics ICC 95 %CI = 0.83-0.90; direct kinematics ICC 95 %CI = 0.80-0.93). For certain tasks and joints, keypoint-derived inverse kinematics resulted in greater reliability (up to 0.47 ICC) and smaller minimal detectable changes (up to 13°) than direct kinematics. Performing 2-4 trials was sufficient to maximize reliability for most tasks. A single markerless depth camera can reliably measure lower limb joint angles, and skeletal model-constrained inverse kinematics improves lower limb joint angle reliability for certain tasks and joints.


Assuntos
Articulação do Quadril , Humanos , Masculino , Feminino , Adulto , Fenômenos Biomecânicos , Reprodutibilidade dos Testes , Articulação do Quadril/fisiologia , Articulação do Joelho/fisiologia , Amplitude de Movimento Articular/fisiologia , Extremidade Inferior/fisiologia , Modelos Biológicos , Movimento/fisiologia , Adulto Jovem
2.
Mar Environ Res ; 199: 106611, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38936260

RESUMO

Reef fish communities are shaped by historical and ecological factors, including abiotic and biotic mechanisms at different spatial scales, determining species composition, abundance and biomass. The oceanic islands in the Mid-Atlantic Ridge (St. Peter and St. Paul's Archipelago - SPSPA, Ascension, and St. Helena), exhibiting differences in community structure along a 14-degree latitudinal and a 10 °C thermal gradient. We investigate the influence of sea surface temperature, area, age, isolation and phosphate on reef fish community structures. Reef fish trophic structure varies significantly across the islands, with planktivores and herbivore-detritivores showing the highest abundances in SPSPA and Ascension, while less abundant in St. Helena, aligning with the thermal gradient. Variations in reef fish community structures were predominantly influenced by thermal regimes, corroborating the expansion of species' thermal niche breadth at higher latitudes and lower temperatures. This study highlights that in addition to biogeographic factors, temperature is pivotal on shaping oceanic island reef fish community structure.

4.
J Glob Antimicrob Resist ; 38: 49-65, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38789083

RESUMO

OBJECTIVES: The COVID-19 pandemic disrupted antimicrobial stewardship and infection prevention operations worldwide, raising concerns for an acceleration of antimicrobial resistance (AMR). Therefore, we aimed to define the scope of peer reviewed research comparing AMR in inpatient bacterial clinical cultures before and after the start of the COVID-19 pandemic. METHODS: We conducted a scoping review and searched PubMed, Scopus, and Web of Science through 15 June 2023. Our inclusion criteria were: (1) English language, (2) primary evidence, (3) peer-reviewed, (4) clinical culture data from humans, (5) AMR data for at least one bacterial order/species, (6) inpatient setting, (7) use of statistical testing to evaluate AMR data before and during the COVID-19 pandemic. Reviewers extracted country, study design, type of analysis, study period, setting and population, number of positive cultures or isolates, culture type(s), method of AMR analysis, organisms, and AMR results. Study results were organised by organism and antibiotic class or resistance mechanism. AMR results are also summarised by individual study and across all studies. RESULTS: In total, 4805 articles were identified with 55 papers meeting inclusion criteria. Acinetobacter baumannii, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Staphylococcus aureus were the most commonly studied organisms. There were 464 bacterial AMR results across all studies with 82 (18%) increase, 71 (15%) decrease, and 311 (67%) no change results. CONCLUSIONS: The literature examining the impact of COVID-19 on AMR among inpatients is diverse with most results reflecting no change pre/post pandemic. Ongoing inquiry is needed into evolving patterns in AMR post COVID-19.

5.
Emerg Infect Dis ; 30(6): 1296-1298, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38781986

RESUMO

Cetacean morbillivirus is an etiologic agent associated with strandings of live and dead cetacean species occurring sporadically or as epizootics worldwide. We report 2 cases of cetacean morbillivirus in humpback whales (Megaptera novaeangliae) in Brazil and describe the anatomopathological, immunohistochemical, and molecular characterization findings in the specimens.


Assuntos
Jubarte , Infecções por Morbillivirus , Morbillivirus , Filogenia , Animais , Morbillivirus/isolamento & purificação , Morbillivirus/genética , Morbillivirus/classificação , Brasil , Infecções por Morbillivirus/veterinária
6.
Aging Cell ; 23(5): e14113, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38708778

RESUMO

Chronic conditions associated with aging have proven difficult to prevent or treat. Senescence is a cell fate defined by loss of proliferative capacity and the development of a pro-inflammatory senescence-associated secretory phenotype comprised of cytokines/chemokines, proteases, and other factors that promotes age-related diseases. Specifically, an increase in senescent peripheral blood mononuclear cells (PBMCs), including T cells, is associated with conditions like frailty, rheumatoid arthritis, and bone loss. However, it is unknown if the percentage of senescent PBMCs associated with age-associated orthopedic decline could be used for potential diagnostic or prognostic use in orthopedics. Here, we report senescent cell detection using the fluorescent compound C12FDG to quantify PBMCs senescence across a large cohort of healthy and osteoarthritic patients. There is an increase in the percent of circulating C12FDG+ PBMCs that is commensurate with increases in age and senescence-related serum biomarkers. Interestingly, C12FDG+ PBMCs and T cells also were found to be elevated in patients with mild to moderate osteoarthritis, a progressive joint disease that is strongly associated with inflammation. The percent of C12FDG+ PBMCs and age-related serum biomarkers were decreased in a small subgroup of study participants taking the senolytic drug fisetin. These results demonstrate quantifiable measurements in a large group of participants that could create a composite score of healthy aging sensitive enough to detect changes following senolytic therapy and may predict age-related orthopedic decline. Detection of peripheral senescence in PBMCs and subsets using C12FDG may be clinically useful for quantifying cellular senescence and determining how and if it plays a pathological role in osteoarthritic progression.


Assuntos
Biomarcadores , Senescência Celular , Osteoartrite , Fenótipo , Humanos , Osteoartrite/diagnóstico por imagem , Osteoartrite/patologia , Osteoartrite/metabolismo , Biomarcadores/metabolismo , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Leucócitos Mononucleares/metabolismo , Envelhecimento/patologia , Idoso de 80 Anos ou mais
7.
Am J Infect Control ; 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38719159

RESUMO

OBJECTIVE: Blood cultures (BCx) are important for selecting appropriate antibiotic treatment. Ordering BCx for conditions with a low probability of bacteremia has limited utility, thus improved guidance for ordering BCx is needed. Inpatient studies have implemented BCx algorithms, but no studies examine the intervention in an Emergency Department (ED) setting. METHODS: We performed a quasi-experimental pre and postintervention study from January 12, 2020, to October 31, 2023, at a single academic adult ED and implemented a BCx algorithm. The primary outcome was the blood culture event rates (BCE per 100 ED admissions) pre and postintervention. Secondary outcomes included adverse event rates (30-day ED and hospital readmission and antibiotic days of therapy). Seven ED physicians and APP reviewed BCx for appropriateness, with monthly feedback provided to ED leadership and physicians. RESULTS: After the BCx algorithm implementation, the BCE rate decreased from 12.17 BCE/100 ED admissions to 10.50 BCE/100 ED admissions. Of the 3,478 reviewed BCE, we adjudicated 2,153 BCE (62%) as appropriate, 653 (19%) as inappropriate, and 672 (19%) as uncertain. Adverse safety events were not statistically different pre and postintervention. CONCLUSIONS: Implementation of an ED BCx algorithm demonstrated a reduction in BCE, without increased adverse safety events. Future studies should compare outcomes of BCx algorithm implementation in a community hospital ED without intensive chart review.

8.
J Intensive Care Med ; : 8850666241254736, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38751351

RESUMO

Background: Despite high negative predictive values (NPVs) seen with methicillin-resistant Staphylococcus aureus (MRSA) nares polymerase chain reaction (PCR) assays, utilization of both respiratory sample Gram stain and MRSA nares PCR in patients with pneumonia may contribute to overuse of laboratory resources. The purpose of this study was to evaluate if a Gram stain demonstrating no Gram-positive organisms from a respiratory sample is sufficient to allow for de-escalation of vancomycin therapy. Methods: This single center study retrospectively identified intensive care unit (ICU) patients started on vancomycin for presumed pneumonia at University of Wisconsin (UW) Health in Madison, WI between August 2022 and March 2023. Patients with respiratory sample demonstrating no Gram-positives on Gram stain met inclusion criteria if the sample was ordered within 24 h of vancomycin initiation. The primary outcome was NPV of respiratory sample Gram stain demonstrating no Gram-positive organisms with respect to MRSA detection of the respiratory culture. Secondary outcomes included the NPV of combined MRSA nares PCR plus respiratory sample Gram stain, and difference in time to event in patients that had both a respiratory sample and MRSA nares PCR ordered. Results: A total of 370 patients were screened for study eligibility; of which 99 patients met inclusion criteria. NPV of respiratory sample Gram stain was 99% for MRSA culture. The combined NPV of respiratory sample Gram stain plus MRSA nares PCR was 98.9% for MRSA culture (n = 88). Respiratory sample was ordered 2.3 h faster compared to MRSA nares PCR (4.3 vs 6.6 h, P = .036). Respiratory sample Gram stain resulted 4.5 h faster compared to MRSA nares PCR (10.7 vs 15.2 h, P = .002). Conclusion: Respiratory sample Gram stains demonstrating no Gram-positive organisms may be used to de-escalate vancomycin and deprioritize the use of MRSA nares PCR.

9.
Diagn Microbiol Infect Dis ; 109(2): 116245, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38522368

RESUMO

Research and development of innovative antimicrobials is paramount to addressing the antimicrobial resistance threat. Although antimicrobial discovery and development has increased, difficulties have emerged in the pharmaceutical industry after market approval. In this minireview, we summarize clinical trial data on recently approved antibiotics, calculate incremental cost-effectiveness ratio (ICER) values, and explore ways to adapt ICER calculations to the limitations of antimicrobial clinical trial design. We provide a systematic review and analysis of randomized, controlled studies of antibiotics approved from 2014 - 2022 and extracted the relevant clinical data. Adapted-ICER (aICER) calculations were conducted using the primary condition-specific outcome that was reported in each study (percent mortality or percent cure rate). The literature search identified 18 studies for the 8 total antibiotics which met inclusion criteria and contained data required for aICER calculation. aICER values ranged from -$17,374 to $4,966 per percent mortality and -$43,931 to $2,529 per percent cure rate. With regards to mortality, ceftolozane/tazobactam and imipenem/cilastatin/relebactam proved cost efficacious, with aICER values of $4,965 per percent mortality and $1,955 per percent mortality respectively. Finding value in novel antibiotic agents is imperative to further justifying their development, and aICER values are the most common method of determining value in healthcare. The current outcomes of clinical trials are difficult to translate to aICER, which most effectively use Quality-Adjusted Life Years (QALY) as the quality standard in other fields such as oncology. Future antimicrobial trials should consider introducing methods of assessing measures of health gain such as QALY to better translate the value of novel antimicrobials in healthcare.


Assuntos
Antibacterianos , Análise Custo-Benefício , Humanos , Antibacterianos/uso terapêutico , Antibacterianos/economia , Doenças Transmissíveis/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto
10.
Curr Oncol Rep ; 26(3): 258-271, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38376626

RESUMO

PURPOSE OF REVIEW: This work consists in a literature review on the current state of knowledge regarding the oral management of patients with a history of head and neck cancer (HNC), corroborated by clinical cases and illustrated by clear infographic summaries. It aims to provide healthcare professionals with a comprehensive overview of the oral health status of HCN patients. RECENT FINDINGS: Head and neck cancers (HNCs) represent the seventh most common type of cancer worldwide, with over 660,000 annual new cases. Despite the significant negative impact of HNCs on oral health, patients often receive no or inappropriate oral care while the significant impact of oral pathologies on cancer prognosis is commonly underestimated. This work (i) describes the oral cavity during and after HNC through the prism of care complexity and (ii) highlights several potential key factors that could worsen long-time patients' prognosis and quality of life. By investigating the biological, microbiological, functional, and psychological dimensions of the interrelationships between HNCs and oral health, the authors explored the barriers and benefits of a targeted oral healthcare pathway. This article emphasizes the importance of multidisciplinary care and highlights the need for further research elucidating the intricate relationships between oral health and HNCs, particularly through the microbiota.


Assuntos
Neoplasias de Cabeça e Pescoço , Saúde Bucal , Humanos , Qualidade de Vida/psicologia , Neoplasias de Cabeça e Pescoço/terapia , Atenção à Saúde , Pessoal de Saúde
11.
J Vet Diagn Invest ; 36(2): 278-282, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38336609

RESUMO

We describe an unusual outbreak of mortality in suckling piglets following the misadministration of an oral vaccine against Salmonella Typhimurium and Salmonella Choleraesuis. Within 3-48 h of vaccination of a batch of ~700 piglets, ~300 developed marked swelling in the dorsal neck region, respiratory distress, fever, recumbency, and apathy. In total, ~100 died, and 4 were submitted for autopsy. Gross and microscopic lesions consisted of focally extensive areas of purple discoloration in the skin of the cervical region, associated with edema and hemorrhage in the subcutis and muscles. Additionally, there was interstitial pneumonia with marked interlobular edema and mild fibrinous pleuritis. Aerobic bacterial culture identified Salmonella Typhimurium (3 cases) and Salmonella Choleraesuis (1 case) in samples of skeletal muscle and lung and from pleural swab samples. Marked immunostaining against Salmonella spp. was observed in the skeletal muscle of the cervical region, as well as in blood vessels and macrophages from the lung, liver, spleen, and kidney. We concluded that inappropriate intramuscular administration of an oral vaccine against Salmonella resulted in septicemia and death in a batch of piglets.


Assuntos
Salmonelose Animal , Salmonella , Doenças dos Suínos , Suínos , Animais , Salmonelose Animal/microbiologia , Doenças dos Suínos/microbiologia , Salmonella typhimurium , Vacinas Atenuadas , Edema/veterinária , Administração Oral
12.
Transplant Proc ; 56(2): 434-439, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38355369

RESUMO

BACKGROUND: Cytomegalovirus (CMV) infections are common opportunistic infections in solid organ transplants (SOT) with increased health care resource USE and costs. Costs are further increased with ganciclovir-resistance (GR). This study aimed to evaluate the real-world impact of conversion to oral step-down therapy on duration of foscarnet and hospital length of stay (LOS) for treatment of GR-CMV infections in SOT. METHODS: This study included adult recipients of kidney or lung transplants who received foscarnet for genotypically documented GR-CMV while admitted at the University of Wisconsin Hospital from October 1, 2015, to January 31, 2022. Patients in the oral step-down group were converted from standard of care (SOC; foscarnet) to maribavir or letermovir; patients in the historical control group were treated with SOC. RESULTS: Twenty-six patients met the inclusion criteria: 5 in the intervention group and 21 in the SOC group. The median viral load at foscarnet initiation was 11,435 IU/mL. Patients who received oral step-down conversion had shorter mean foscarnet duration than those who received SOC (7 ± 4 vs 37 ± 25 days, P = .017). Mean hospital LOS in the oral step-down group (16 ± 3 days) was shorter than the SOC group (33 ± 21 days; P < .001). In the SOC group, 9 patients lost their graft, and 9 patients died; 2 deaths were attributed to CMV. There were 2 deaths in the oral step-down group, neither of which was attributed to CMV. CONCLUSION AND RELEVANCE: In this real-world case series of patients receiving treatment for GR-CMV infection, oral step-down conversion decreased foscarnet therapy duration and hospital LOS. Future studies are needed to evaluate better the effect of oral step-down in treating GR-CMV infection on treatment duration and cost-savings.


Assuntos
Infecções por Citomegalovirus , Transplante de Órgãos , Adulto , Humanos , Citomegalovirus , Foscarnet/uso terapêutico , Antivirais/uso terapêutico , Ganciclovir/uso terapêutico , Infecções por Citomegalovirus/diagnóstico , Infecções por Citomegalovirus/tratamento farmacológico , Infecções por Citomegalovirus/etiologia , Transplante de Órgãos/efeitos adversos , Transplantados
14.
Am J Health Syst Pharm ; 81(4): 120-128, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-37897218

RESUMO

PURPOSE: The fluoroquinolone restriction for the prevention of Clostridioides difficile infection (FIRST) trial is a multisite clinical study in which sites carry out a preauthorization process via electronic health record-based best-practice alert (BPA) to optimize the use of fluoroquinolone antibiotics in acute care settings. Our research team worked closely with clinical implementation coordinators to facilitate the dissemination and implementation of this evidence-based intervention. Clinical implementation coordinators within the antibiotic stewardship team (AST) played a pivotal role in the implementation process; however, considerable research is needed to further understand their role. In this study, we aimed to (1) describe the roles and responsibilities of clinical implementation coordinators within ASTs and (2) identify facilitators and barriers coordinators experienced within the implementation process. METHODS: We conducted a directed content analysis of semistructured interviews, implementation diaries, and check-in meetings utilizing the conceptual framework of middle managers' roles in innovation implementation in healthcare from Urquhart et al. RESULTS: Clinical implementation coordinators performed a variety of roles vital to the implementation's success, including gathering and compiling information for BPA design, preparing staff, organizing meetings, connecting relevant stakeholders, evaluating clinical efficacy, and participating in the innovation as clinicians. Coordinators identified organizational staffing models and COVID-19 interruptions as the main barriers. Facilitators included AST empowerment, positive relationships with staff and oversight/governance committees, and using diverse implementation strategies. CONCLUSION: When implementing healthcare innovations, clinical implementation coordinators facilitated the implementation process through their roles and responsibilities and acted as strategic partners in improving the adoption and sustainability of a fluoroquinolone preauthorization protocol.


Assuntos
COVID-19 , Medicina Baseada em Evidências , Humanos , Atenção à Saúde , Modelos Organizacionais , Fluoroquinolonas/uso terapêutico
15.
Infect Control Hosp Epidemiol ; 45(5): 667-669, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38151334

RESUMO

We evaluated diagnostic test and antibiotic utilization among 252 patients from 11 US hospitals who were evaluated for coronavirus disease 2019 (COVID-19) pneumonia during the severe acute respiratory coronavirus virus 2 (SARS-CoV-2) omicron variant pandemic wave. In our cohort, antibiotic use remained high (62%) among SARS-CoV-2-positive patients and even higher among those who underwent procalcitonin testing (68%).


Assuntos
COVID-19 , Pneumonia , Humanos , Pacientes Internados , SARS-CoV-2 , Técnicas e Procedimentos Diagnósticos , Antibacterianos , Teste para COVID-19
16.
Chem Sci ; 15(1): 213-219, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38131093

RESUMO

The methoxime group has emerged as a versatile directing group for a variety of C-H functionalizations. Despite its importance as a powerful functional handle, conversion of methoximes to the parent ketone, which is often desired, usually requires harsh and functional group intolerant reaction conditions. Therefore, the application of methoximes and their subsequent conversion to the corresponding ketone in a late-stage context can be problematic. Here, we present an alternative set of conditions to achieve mild and functional group tolerant conversion of methoximes to the parent ketones using photoexcited nitroarenes. The utility of this methodology is showcased in its application in the total synthesis of cephanolide D. Furthermore, mechanistic insight into this transformation obtained using isotope labeling studies as well as the analysis of reaction byproducts is provided.

17.
Acc Chem Res ; 56(23): 3515-3524, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37992288

RESUMO

Conspectus"Synthesis by design" is often considered to be the primary goal of chemists who make molecules and materials. Synthetic chemists usually have in mind a target they want to make, and they want to be able to design a pathway that can get them to that target as quickly and efficiently as possible. Chemists who synthesize refractory solids, which have melting points above 1000 °C and are often chemically inert at these high temperatures, have access to only a small number of synthetic strategies due to the need to overcome solid-state diffusion, which is the rate-limiting step in such reactions. The use of extremely high temperatures to facilitate diffusion among two or more refractory solids, which precedes any chemical reaction that must occur, generally drives the system to form only the product that is the most thermodynamically stable-the global minimum on an energy landscape-for a certain combination of elements. When trying to target a different product in the same system, one generally cannot rely on thermally driven reactions. Lower-temperature reactions that side step this diffusion limitation can succeed where high temperatures fail by providing access to local minima on an energy landscape. These local minima represent metastable phases that are primed for synthesis, but only if an appropriate pathway and set of reactions can be identified. It is therefore important to develop and understand low-temperature, or "soft", chemical reactions in "hard" refractory systems. These reactions allow us to apply the retrosynthetic framework that molecular chemists rely on to systems where chemists have not previously had such control over reactions, reactivities, and metastable product formation.In this Account, we discuss the development of soft chemical reactions of hard materials in the context of a class of layered, refractory metal borides that are precursors to an emerging family of two-dimensional nanomaterials. Layered ternary metal boride phases such as MoAlB have layers of metal borides, which are chemically unreactive, interleaved with layers of aluminum, which are reactive. Some of the interlayer aluminum can be deintercalated at room temperature in dilute aqueous sodium hydroxide, transforming stable MoAlB into destabilized MoAl1-xB. Mild thermal treatment of submicrometer grains of this destabilized MoAl1-xB sample allows it to traverse the energy landscape and crystallize as Mo2AlB2, a metastable compound. Further thermal treatment transforms Mo2AlB2 into a Mo2AlB2-alumina nanolaminate and ultimately mesoporous MoB, all through continued traversing of the energy landscape using mild chemical and thermal treatments. Similar topochemical manipulations, which maintain structure but change composition, are emerging for other MAB phases and are opening the door to new types of metastable compounds and nanostructured materials in traditionally refractory systems.

18.
Cell Rep ; 42(10): 113300, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37858472

RESUMO

All vertebrate genomes encode for three large histone H2A variants that have an additional metabolite-binding globular macrodomain module, macroH2A. MacroH2A variants impact heterochromatin organization and transcription regulation and establish a barrier for cellular reprogramming. However, the mechanisms of how macroH2A is incorporated into chromatin and the identity of any chaperones required for histone deposition remain elusive. Here, we develop a split-GFP-based assay for chromatin incorporation and use it to conduct a genome-wide mutagenesis screen in haploid human cells to identify proteins that regulate macroH2A dynamics. We show that the histone chaperone ANP32B is a regulator of macroH2A deposition. ANP32B associates with macroH2A in cells and in vitro binds to histones with low nanomolar affinity. In vitro nucleosome assembly assays show that ANP32B stimulates deposition of macroH2A-H2B and not of H2A-H2B onto tetrasomes. In cells, depletion of ANP32B strongly affects global macroH2A chromatin incorporation, revealing ANP32B as a macroH2A histone chaperone.


Assuntos
Cromatina , Histonas , Humanos , Histonas/metabolismo , Chaperonas de Histonas/metabolismo , Regulação da Expressão Gênica , Chaperonas Moleculares/metabolismo , Nucleossomos , Proteínas Nucleares/metabolismo
19.
Biochem Biophys Res Commun ; 683: 149090, 2023 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-37862779

RESUMO

Snake venoms are known to be major sources of peptides with different pharmacological properties. In this study, we comprehensively explored the venom peptidomes of three specimens of Lachesismuta, the largest venomous snake in South America, using mass spectrometry techniques. The analysis revealed 19 main chromatographic peaks common to all specimens. A total of 151 peptides were identified, including 69 from a metalloproteinase, 58 from the BPP-CNP precursor, and 24 from a l-amino acid oxidase. To our knowledge, 126 of these peptides were reported for the first time in this work, including a new SVMP-derived peptide fragment, Lm-10a. Our findings highlight the dynamic nature of toxin maturation in snake venoms, driven by proteolytic processing, post-translational modifications, and cryptide formation.


Assuntos
Bradicinina , L-Aminoácido Oxidase , L-Aminoácido Oxidase/química , Peptídeos/química , Venenos de Serpentes , Metaloproteases
20.
Nat Immunol ; 24(11): 1947-1959, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37845489

RESUMO

Age-associated changes in the T cell compartment are well described. However, limitations of current single-modal or bimodal single-cell assays, including flow cytometry, RNA-seq (RNA sequencing) and CITE-seq (cellular indexing of transcriptomes and epitopes by sequencing), have restricted our ability to deconvolve more complex cellular and molecular changes. Here, we profile >300,000 single T cells from healthy children (aged 11-13 years) and older adults (aged 55-65 years) by using the trimodal assay TEA-seq (single-cell analysis of mRNA transcripts, surface protein epitopes and chromatin accessibility), which revealed that molecular programming of T cell subsets shifts toward a more activated basal state with age. Naive CD4+ T cells, considered relatively resistant to aging, exhibited pronounced transcriptional and epigenetic reprogramming. Moreover, we discovered a novel CD8αα+ T cell subset lost with age that is epigenetically poised for rapid effector responses and has distinct inhibitory, costimulatory and tissue-homing properties. Together, these data reveal new insights into age-associated changes in the T cell compartment that may contribute to differential immune responses.


Assuntos
Subpopulações de Linfócitos T , Transcriptoma , Criança , Humanos , Idoso , Envelhecimento/genética , Epitopos/metabolismo , Análise de Célula Única
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