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1.
Nat Commun ; 15(1): 5394, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38918428

RESUMO

Adipose tissue macrophages (ATMs) influence obesity-associated metabolic dysfunction, but the mechanisms by which they do so are not well understood. We show that miR-6236 is a bona fide miRNA that is secreted by ATMs during obesity. Global or myeloid cell-specific deletion of miR-6236 aggravates obesity-associated adipose tissue insulin resistance, hyperglycemia, hyperinsulinemia, and hyperlipidemia. miR-6236 augments adipocyte insulin sensitivity by inhibiting translation of negative regulators of insulin signaling, including PTEN. The human genome harbors a miR-6236 homolog that is highly expressed in the serum and adipose tissue of obese people. hsa-MIR-6236 expression negatively correlates with hyperglycemia and glucose intolerance, and positively correlates with insulin sensitivity. Together, our findings establish miR-6236 as an ATM-secreted miRNA that potentiates adipocyte insulin signaling and protects against metabolic dysfunction during obesity.


Assuntos
Adipócitos , Hiperglicemia , Resistência à Insulina , Insulina , MicroRNAs , Obesidade , PTEN Fosfo-Hidrolase , Transdução de Sinais , MicroRNAs/metabolismo , MicroRNAs/genética , Obesidade/metabolismo , Obesidade/genética , Animais , Adipócitos/metabolismo , Hiperglicemia/metabolismo , Hiperglicemia/genética , Humanos , Insulina/metabolismo , Resistência à Insulina/genética , Camundongos , Masculino , PTEN Fosfo-Hidrolase/metabolismo , PTEN Fosfo-Hidrolase/genética , Camundongos Endogâmicos C57BL , Macrófagos/metabolismo , Tecido Adiposo/metabolismo , Células Mieloides/metabolismo , Camundongos Knockout , Hiperinsulinismo/metabolismo , Hiperinsulinismo/genética
2.
mSphere ; 9(6): e0008124, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38837404

RESUMO

In a healthy colon, the stratified mucus layer serves as a crucial innate immune barrier to protect the epithelium from microbes. Mucins are complex glycoproteins that serve as a nutrient source for resident microflora and can be exploited by pathogens. We aimed to understand how the intestinal pathogen, Clostridioides difficile, independently uses or manipulates mucus to its benefit, without contributions from members of the microbiota. Using a 2-D primary human intestinal epithelial cell model to generate physiologic mucus, we assessed C. difficile-mucus interactions through growth assays, RNA-Seq, biophysical characterization of mucus, and contextualized metabolic modeling. We found that host-derived mucus promotes C. difficile growth both in vitro and in an infection model. RNA-Seq revealed significant upregulation of genes related to central metabolism in response to mucus, including genes involved in sugar uptake, the Wood-Ljungdahl pathway, and the glycine cleavage system. In addition, we identified differential expression of genes related to sensing and transcriptional control. Analysis of mutants with deletions in highly upregulated genes reflected the complexity of C. difficile-mucus interactions, with potential interplay between sensing and growth. Mucus also stimulated biofilm formation in vitro, which may in turn alter the viscoelastic properties of mucus. Context-specific metabolic modeling confirmed differential metabolism and the predicted importance of enzymes related to serine and glycine catabolism with mucus. Subsequent growth experiments supported these findings, indicating mucus is an important source of serine. Our results better define responses of C. difficile to human gastrointestinal mucus and highlight flexibility in metabolism that may influence pathogenesis. IMPORTANCE: Clostridioides difficile results in upward of 250,000 infections and 12,000 deaths annually in the United States. Community-acquired infections continue to rise, and recurrent disease is common, emphasizing a vital need to understand C. difficile pathogenesis. C. difficile undoubtedly interacts with colonic mucus, but the extent to which the pathogen can independently respond to and take advantage of this niche has not been explored extensively. Moreover, the metabolic complexity of C. difficile remains poorly understood but likely impacts its capacity to grow and persist in the host. Here, we demonstrate that C. difficile uses native colonic mucus for growth, indicating C. difficile possesses mechanisms to exploit the mucosal niche. Furthermore, mucus induces metabolic shifts and biofilm formation in C. difficile, which has potential ramifications for intestinal colonization. Overall, our work is crucial to better understand the dynamics of C. difficile-mucus interactions in the context of the human gut.


Assuntos
Biofilmes , Clostridioides difficile , Regulação Bacteriana da Expressão Gênica , Muco , Clostridioides difficile/genética , Clostridioides difficile/fisiologia , Clostridioides difficile/metabolismo , Biofilmes/crescimento & desenvolvimento , Humanos , Muco/microbiologia , Muco/metabolismo , Células Epiteliais/microbiologia , Mucosa Intestinal/microbiologia , Mucosa Intestinal/metabolismo , Infecções por Clostridium/microbiologia
3.
EMBO J ; 43(14): 2878-2907, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38816652

RESUMO

In mice, γδ-T lymphocytes that express the co-stimulatory molecule, CD27, are committed to the IFNγ-producing lineage during thymic development. In the periphery, these cells play a critical role in host defense and anti-tumor immunity. Unlike αß-T cells that rely on MHC-presented peptides to drive their terminal differentiation, it is unclear whether MHC-unrestricted γδ-T cells undergo further functional maturation after exiting the thymus. Here, we provide evidence of phenotypic and functional diversity within peripheral IFNγ-producing γδ T cells. We found that CD27+ Ly6C- cells convert into CD27+Ly6C+ cells, and these CD27+Ly6C+ cells control cancer progression in mice, while the CD27+Ly6C- cells cannot. The gene signatures of these two subsets were highly analogous to human immature and mature γδ-T cells, indicative of conservation across species. We show that IL-27 supports the cytotoxic phenotype and function of mouse CD27+Ly6C+ cells and human Vδ2+ cells, while IL-27 is dispensable for mouse CD27+Ly6C- cell and human Vδ1+ cell functions. These data reveal increased complexity within IFNγ-producing γδ-T cells, comprising immature and terminally differentiated subsets, that offer new insights into unconventional T-cell biology.


Assuntos
Antígenos Ly , Receptores de Antígenos de Linfócitos T gama-delta , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral , Animais , Camundongos , Antígenos Ly/metabolismo , Antígenos Ly/genética , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismo , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/genética , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/imunologia , Humanos , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/genética , Interferon gama/metabolismo , Interferon gama/imunologia , Interleucina-27/metabolismo , Interleucina-27/genética , Diferenciação Celular/imunologia , Camundongos Endogâmicos C57BL , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismo
4.
BMJ Open ; 14(5): e083046, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38777590

RESUMO

INTRODUCTION: Knee osteoarthritis (OA) is the most prevalent arthritis type and a leading cause of chronic mobility disability. While pain medications provide only symptomatic pain relief; growing evidence suggests pentosan polysulfate sodium (PPS) is chondroprotective and could have anti-inflammatory effects in knee OA. This study aims to explore the efficacy and safety of oral PPS in symptomatic knee OA with dyslipidaemia. METHODS AND ANALYSIS: MaRVeL is a phase II, single-centre, parallel, superiority trial which will be conducted at Royal North Shore Hospital, Sydney, Australia. 92 participants (46 per arm) aged 40 and over with painful knee OA and mild to moderate structural change on X-ray (Kellgren and Lawrence grade 2 or 3) will be recruited from the community and randomly allocated to receive two cycles of either oral PPS or placebo for 5 weeks starting at baseline and week 11. Primary outcome will be the 16-week change in overall average knee pain severity measured using an 11-point Numeric Rating Scale. Main secondary outcomes include change in knee pain, patient global assessment, physical function, quality of life and other structural changes. A biostatistician blinded to allocation groups will perform the statistical analysis according to the intention-to-treat principle. ETHICS AND DISSEMINATION: The protocol has been approved by the NSLHD Human Research Ethics Committee (HREC) (2021/ETH00315). All participants will provide written informed consent online. Study results will be disseminated through conferences, social media and academic publications. TRIAL REGISTRATION NUMBERS: Australian New Zealand Clinical Trial Registry (ACTRN12621000654853); U1111-1265-3750.


Assuntos
Dislipidemias , Osteoartrite do Joelho , Poliéster Sulfúrico de Pentosana , Humanos , Osteoartrite do Joelho/tratamento farmacológico , Poliéster Sulfúrico de Pentosana/uso terapêutico , Poliéster Sulfúrico de Pentosana/administração & dosagem , Dislipidemias/tratamento farmacológico , Dislipidemias/complicações , Qualidade de Vida , Masculino , Resultado do Tratamento , Feminino , Pessoa de Meia-Idade , Ensaios Clínicos Fase II como Assunto , Austrália , Medição da Dor , Adulto
5.
Front Bioeng Biotechnol ; 12: 1386816, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38784769

RESUMO

Introduction: Bone tumors, characterized by diverse locations and shapes, often necessitate surgical excision followed by custom implant placement to facilitate targeted bone reconstruction. Leveraging additive manufacturing, patient-specific implants can be precisely tailored with complex geometries and desired stiffness, enhancing their suitability for bone ingrowth. Methods: In this work, a finite element model is employed to assess patient-specific lattice implants in femur bones. Our model is validated using experimental data obtained from an animal study (n = 9). Results: The results demonstrate the accuracy of the proposed finite element model in predicting the implant mechanical behavior. The model was used to investigate the influence of reducing the elastic modulus of a solid Ti6Al4V implant by tenfold, revealing that such a reduction had no significant impact on bone behavior under maximum compression and torsion loading. This finding suggests a potential avenue for reducing the endoprosthesis modulus without compromising bone integrity. Discussion: Our research suggests that employing fully lattice implants not only facilitates bone ingrowth but also has the potential to reduce overall implant stiffness. This reduction is crucial in preventing significant bone remodeling associated with stress shielding, a challenge often associated with the high stiffness of fully solid implants. The study highlights the mechanical benefits of utilizing lattice structures in implant design for enhanced patient outcomes.

6.
J Biomed Opt ; 29(4): 046004, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38690122

RESUMO

Significance: Assessing the nanostructure of polymer solutions and biofluids is broadly useful for understanding drug delivery and disease progression and for monitoring therapy. Aim: Our objective is to quantify bronchial mucus solids concentration (wt. %) during hypertonic saline (HTS) treatment in vitro via nanostructurally constrained diffusion of gold nanorods (GNRs) monitored by polarization-sensitive optical coherence tomography (PS-OCT). Approach: Using PS-OCT, we quantified GNR translational (DT) and rotational (DR) diffusion coefficients within polyethylene oxide solutions (0 to 3 wt. %) and human bronchial epithelial cell (hBEC) mucus (0 to 6.4 wt. %). Interpolation of DT and DR data is used to develop an assay to quantify mucus concentration. The assay is demonstrated on the mucus layer of an air-liquid interface hBEC culture during HTS treatment. Results: In polymer solutions and mucus, DT and DR monotonically decrease with increasing concentration. DR is more sensitive than DT to changes above 1.5 wt. % of mucus and exhibits less intrasample variability. Mucus on HTS-treated hBEC cultures exhibits dynamic mixing from cilia. A region of hard-packed mucus is revealed by DR measurements. Conclusions: The extended dynamic range afforded by simultaneous measurement of DT and DR of GNRs using PS-OCT enables resolving concentration of the bronchial mucus layer over a range from healthy to disease in depth and time during HTS treatment in vitro.


Assuntos
Ouro , Muco , Nanotubos , Tomografia de Coerência Óptica , Tomografia de Coerência Óptica/métodos , Humanos , Nanotubos/química , Ouro/química , Muco/química , Muco/metabolismo , Difusão , Brônquios/diagnóstico por imagem , Células Epiteliais/química , Células Epiteliais/metabolismo , Solução Salina Hipertônica/farmacologia , Solução Salina Hipertônica/química , Células Cultivadas
7.
J Burn Care Res ; 45(4): 822-827, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-38602153

RESUMO

Cultured epidermal autografts (CEA) have since become more prevalent in the treatment of burn-injured patients with limited available donor sites for adequate wound closure, resulting in decreased mortality rates and an increased number of these patients requiring burn therapy services to achieve optimal functional outcomes at discharge. However, the use and postoperative management of CEA continue to be controversial due large to the physiological fragility and expense of CEA, leading to variable postoperative treatment practices across burn centers. As such, minimal research is available regarding patient outcomes following CEA application, specifically related to burn therapy intervention. Thus, a retrospective chart review was conducted on a series of 10 patients, 18 years of age or older, admitted to a single, American Burn Association verified burn center, between April 2015 and April 2023, who required CEA and received pre- and postoperative treatment by burn therapists in accordance with center-specific burn rehabilitation guidelines. The resulting patient outcomes, in response to early implementation of therapy interventions post-CEA surgery, demonstrated optimal functional status for patients upon discharge and positive long-term implications.


Assuntos
Queimaduras , Transplante de Pele , Humanos , Queimaduras/cirurgia , Queimaduras/terapia , Estudos Retrospectivos , Masculino , Feminino , Adulto , Transplante de Pele/métodos , Pessoa de Meia-Idade , Autoenxertos , Epiderme/transplante , Resultado do Tratamento , Transplante Autólogo , Unidades de Queimados , Cicatrização
8.
Am J Respir Crit Care Med ; 210(1): 63-76, 2024 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-38626355

RESUMO

Rationale: Bronchiectasis is a pathological dilatation of the bronchi in the respiratory airways associated with environmental or genetic causes (e.g., cystic fibrosis, primary ciliary dyskinesia, and primary immunodeficiency disorders), but most cases remain idiopathic. Objectives: To identify novel genetic defects in unsolved cases of bronchiectasis presenting with severe rhinosinusitis, nasal polyposis, and pulmonary Pseudomonas aeruginosa infection. Methods: DNA was analyzed by next-generation or targeted Sanger sequencing. RNA was analyzed by quantitative PCR and single-cell RNA sequencing. Patient-derived cells, cell cultures, and secretions (mucus, saliva, seminal fluid) were analyzed by Western blotting and immunofluorescence microscopy, and mucociliary activity was measured. Blood serum was analyzed by electrochemiluminescence immunoassay. Protein structure and proteomic analyses were used to assess the impact of a disease-causing founder variant. Measurements and Main Results: We identified biallelic pathogenic variants in WAP four-disulfide core domain 2 (WFDC2) in 11 individuals from 10 unrelated families originating from the United States, Europe, Asia, and Africa. Expression of WFDC2 was detected predominantly in secretory cells of control airway epithelium and also in submucosal glands. We demonstrate that WFDC2 is below the limit of detection in blood serum and hardly detectable in samples of saliva, seminal fluid, and airway surface liquid from WFDC2-deficient individuals. Computer simulations and deglycosylation assays indicate that the disease-causing founder variant p.Cys49Arg structurally hampers glycosylation and, thus, secretion of mature WFDC2. Conclusions: WFDC2 dysfunction defines a novel molecular etiology of bronchiectasis characterized by the deficiency of a secreted component of the airways. A commercially available blood test combined with genetic testing allows its diagnosis.


Assuntos
Bronquiectasia , Pólipos Nasais , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Bronquiectasia/genética , Bronquiectasia/fisiopatologia , Pólipos Nasais/genética , Proteína 2 do Domínio Central WAP de Quatro Dissulfetos
9.
bioRxiv ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38617209

RESUMO

Most human Transcription factors (TFs) genes encode multiple protein isoforms differing in DNA binding domains, effector domains, or other protein regions. The global extent to which this results in functional differences between isoforms remains unknown. Here, we systematically compared 693 isoforms of 246 TF genes, assessing DNA binding, protein binding, transcriptional activation, subcellular localization, and condensate formation. Relative to reference isoforms, two-thirds of alternative TF isoforms exhibit differences in one or more molecular activities, which often could not be predicted from sequence. We observed two primary categories of alternative TF isoforms: "rewirers" and "negative regulators", both of which were associated with differentiation and cancer. Our results support a model wherein the relative expression levels of, and interactions involving, TF isoforms add an understudied layer of complexity to gene regulatory networks, demonstrating the importance of isoform-aware characterization of TF functions and providing a rich resource for further studies.

10.
Clin Plast Surg ; 51(2): 221-232, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38429045

RESUMO

Sustaining an inhalation injury increases the risk of severe complications and mortality. Current evidential support to guide treatment of the injury or subsequent complications is lacking, as studies either exclude inhalation injury or design limit inferences that can be made. Conventional ventilator modes are most commonly used, but there is no consensus on optimal strategies. Settings should be customized to patient tolerance and response. Data for pharmacotherapy adjunctive treatments are limited.


Assuntos
Queimaduras , Insuficiência Respiratória , Humanos , Ventiladores Mecânicos , Consenso , Cuidados Críticos , Insuficiência Respiratória/etiologia , Insuficiência Respiratória/terapia
11.
PLoS One ; 19(2): e0294120, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38394229

RESUMO

People with muco-obstructive pulmonary diseases such as cystic fibrosis (CF) and chronic obstructive pulmonary disease (COPD) often have acute or chronic respiratory infections that are difficult to treat due in part to the accumulation of hyperconcentrated mucus within the airway. Mucus accumulation and obstruction promote chronic inflammation and infection and reduce therapeutic efficacy. Bacterial aggregates in the form of biofilms exhibit increased resistance to mechanical stressors from the immune response (e.g., phagocytosis) and chemical treatments including antibiotics. Herein, combination treatments designed to disrupt the mechanical properties of biofilms and potentiate antibiotic efficacy are investigated against mucus-grown Pseudomonas aeruginosa biofilms and optimized to 1) alter biofilm viscoelastic properties, 2) increase mucociliary transport rates, and 3) reduce bacterial viability. A disulfide bond reducing agent (tris(2-carboxyethyl)phosphine, TCEP), a surfactant (NP40), a biopolymer (hyaluronic acid, HA), a DNA degradation enzyme (DNase), and an antibiotic (tobramycin) are tested in various combinations to maximize biofilm disruption. The viscoelastic properties of biofilms are quantified with particle tracking microrheology and transport rates are quantified in a mucociliary transport device comprised of fully differentiated primary human bronchial epithelial cells. The combination of the NP40 with hyaluronic acid and tobramycin was the most effective at increasing mucociliary transport rates, decreasing the viscoelastic properties of mucus, and reducing bacterial viability. Multimechanistic targeting of biofilm infections may ultimately result in improved clinical outcomes, and the results of this study may be translated into future in vivo infection models.


Assuntos
Depuração Mucociliar , Infecções por Pseudomonas , Humanos , Pseudomonas aeruginosa , Ácido Hialurônico/farmacologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Tobramicina/farmacologia , Tobramicina/uso terapêutico , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/microbiologia , Biofilmes
12.
Rev. bras. med. esporte ; 30: e2021_0311, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1441310

RESUMO

ABSTRACT Introduction: The severe exercise intensity domain can be defined as the range of work rates or speeds over which VO2max can be elicited. Objectives: Our purpose was to determine if critical speed (running analog of critical power) identifies the lower boundary of the severe domain and to identify the upper boundary of the domain. Methods: Twenty-five individuals performed five running tests to exhaustion, each lasting > 2.5 min and < 16 min. The two-parameter speed vs time-to-exhaustion relationship generated values for critical speed and the three-parameter speed vs time-to-reach-VO2max relationship generated values for the threshold speed above which VO2max can be elicited. The relationships were solved to calculate the minimum time needed to elicit VO2max. Results: Critical speed (3.00 ± 0.38 m·s−1) and the threshold speed above which VO2max can be elicited (2.99 ± 0.37 m·s−1) were correlated (r = 0.83, p < 0.01) and did not differ (p = 0.70), confirming critical speed as the lower boundary of the severe domain. The minimum time needed to elicit VO2max (103 ± 7 s) and the associated highest speed at which VO2max can be elicited (4.98 ± 0.52 m·s−1) identified the upper boundary of the severe domain for these participants. Conclusion: The critical power concept, which requires no metabolic measurements, can be used to identify the lowest speed at which VO2max can be elicited. With addition of metabolic measurements, mathematical modeling can also identify the highest speed and shortest exercise duration at which VO2max can be elicited. Evidence Level I; Validating cohort study with good reference standards.


RESUMEN Introducción: El dominio de la intensidad del ejercicio severo se puede definir como el rango de ritmos o velocidades de trabajo sobre las que se puede obtener el VO2max. Objetivos: Nuestro propósito fue determinar si la velocidad crítica (funcionamiento analógico de potencia crítica) identifica el límite inferior del dominio severo e identificar el límite superior del dominio. Métodos: Veinticinco personas realizaron cinco pruebas de carrera hasta el agotamiento, cada una con una duración de > 2,5 min y <16 min. La relación de dos parámetros de velocidad frente a tiempo de agotamiento generó valores para la velocidad crítica y la relación de tres parámetros de velocidad frente a tiempo de alcance de VO2max generó valores para la velocidad umbral por encima del cual se puede obtener el VO2max. Las relaciones se resolvieron para calcular el tiempo mínimo necesario para obtener el VO2max. Resultados: La velocidad crítica (3,00 ± 0,38 m·s−1) y la velocidad umbral por encima de la cual se puede obtener el VO2max (2,99 ± 0,37 m·s−1) se correlacionaron (r = 0,83, p < 0,01) y no difirieron (p = 0,70), lo que confirma la velocidad crítica como el límite inferior del dominio severo. El tiempo mínimo necesario para obtener el VO2max (103 ± 7 s) y la velocidad más alta asociada a la que se puede obtener el VO2max (4,98 ± 0,52 m·s−1) identificaron el límite superior del dominio severo para estos participantes. Conclusión: El concepto de potencia crítica, que no requiere mediciones metabólicas, se puede utilizar para identificar la velocidad más baja a la que se puede obtener el VO2max. Con la adición de mediciones metabólicas, el modelado matemático también puede identificar la velocidad más alta y la duración más corta del ejercicio a la que se puede obtener VO2max. Nivel de Evidencia I; Estudio de cohortes con alto estándar de referencia.


RESUMO Introdução: O domínio de intensidade de exercício severo pode ser definido como a faixa de taxas de trabalho ou velocidades sobre as quais o VO2max pode ser obtido. Objetivos: Nosso propósito foi determinar se a velocidade crítica (execução analógica da potência crítica) identifica o limite inferior do domínio severo e identificar o limite superior do domínio. Métodos: Vinte e cinco indivíduos realizaram cinco testes de corrida até a exaustão, cada um com duração > 2,5 min e < 16 min. A relação velocidade de dois parâmetros contra tempo até a exaustão gerou valores para a velocidade crítica e a relação velocidade de três parâmetros contra tempo para alcançar o VO2max valores gerados para a velocidade limite acima da qual o VO2max pode ser obtido. As relações foram resolvidas para calcular o tempo mínimo necessário para eliciar o VO2max. Resultados: A velocidade crítica (3,00 ± 0,38 m·s−1) e a velocidade limite acima da qual o VO2max pode ser eliciado (2,99 ± 0,37 m·s−1) foram correlacionadas (r = 0,83, p < 0,01) e não diferiram (p = 0,70), confirmando a velocidade crítica como o limite inferior do domínio grave. O tempo mínimo necessário para eliciar o VO2max (103 ± 7 s) e a maior velocidade associada na qual o VO2max pode ser eliciado (4,98 ± 0,52 m·s−1) identificou o limite superior do domínio severo para esses participantes. Conclusão: O conceito de potência crítica, que não requer medidas metabólicas, pode ser usado para identificar a velocidade mais baixa em que o VO2max pode ser eliciado. Com a adição de medidas metabólicas, a modelagem matemática também pode identificar a velocidade mais alta e a duração mais curta do exercício em que o VO2max pode ser obtido. Nível de Evidência I; Estudo de coorte com alto padrão de referência.

13.
bioRxiv ; 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-38045262

RESUMO

The mucus lining of the human airway epithelium contains two gel-forming mucins, MUC5B and MUC5AC. During progression of cystic fibrosis (CF), mucus hyper-concentrates as its mucin ratio changes, coinciding with formation of insoluble, dense mucus flakes. We explore rheological heterogeneity of this pathology with reconstituted mucus matching three stages of CF progression and particle-tracking of 200 nm and 1 micron diameter beads. We introduce statistical data analysis methods specific to low signal-to-noise data within flakes. Each bead time series is decomposed into: (i) a fractional Brownian motion (fBm) classifier of the pure time-series signal; (ii) high-frequency static and dynamic noise; and (iii) low-frequency deterministic drift. Subsequent analysis focuses on the denoised fBm classifier ensemble from each mucus sample and bead diameter. Every ensemble fails a homogeneity test, compelling clustering methods to assess levels of heterogeneity. The first binary level detects beads within vs. outside flakes. A second binary level detects within-flake bead signals that can vs. cannot be disentangled from the experimental noise floor. We show all denoised ensembles, within- and outside-flakes, fail a homogeneity test, compelling additional clustering; next, all clusters with sufficient data fail a homogeneity test. These levels of heterogeneity are consistent with outcomes from a stochastic phase-separation process, and dictate applying the generalized Stokes-Einstein relation to each bead per cluster per sample, then frequency-domain averaging to assess rheological heterogeneity. Flakes exhibit a spectrum of gel-like and sol-like domains, outside-flake solutions a spectrum of sol-like domains, painting a rheological signature of the phase-separation process underlying flake-burdened mucus.

14.
Health Promot Int ; 38(6)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38128084

RESUMO

Health promotion is conceived as a unifying concept for improving the health of populations. This means addressing the socio-cultural, economic and commercial causes of ill-health, which are necessarily informed by past policies and socio-cultural contexts. However, historical scholarship has rarely figured in health promotion practice or scholarship. This gap resides in the determinants of health, and notably in the analyses of tobacco control and skin cancer prevention, two long-running campaigns that have shaped modern health promotion in Australia. Both highlight a need for understanding the profound impact of history on the present and the value of learning from past successes and failures. Doing so requires integrating historical analyses into existing health promotion scholarship. To achieve this aim, we present a new 'public health humanities' methodology. This novel interdisciplinary framework is conceived as a spectrum in which historical studies integrate with existing health promotion disciplines to solve complex health problems. We draw on the many calls for more interdisciplinarity in health promotion and derive this methodology from proposals in the medical humanities and cognate fields that have wrestled with combining history and present-focused disciplines. Using tobacco control and skin cancer prevention as case studies, we demonstrate how public health humanities uses interdisciplinary teams and shared research questions to generate valuable new knowledge unavailable with traditional methods. Furthermore, we show how it creates evaluation criteria to consider the powerful impact of issues like colonialism on current inequities that hinder health promotion strategies, and from which lessons may be derived for the future.


Assuntos
Saúde Pública , Neoplasias Cutâneas , Humanos , Ciências Humanas , Promoção da Saúde , Currículo , Neoplasias Cutâneas/prevenção & controle
15.
Nat Commun ; 14(1): 6570, 2023 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-37853017

RESUMO

Cooperativity and antagonism between transcription factors (TFs) can drastically modify their binding to regulatory DNA elements. While mapping these relationships between TFs is important for understanding their context-specific functions, existing approaches either rely on DNA binding motif predictions, interrogate one TF at a time, or study individual TFs in parallel. Here, we introduce paired yeast one-hybrid (pY1H) assays to detect cooperativity and antagonism across hundreds of TF-pairs at DNA regions of interest. We provide evidence that a wide variety of TFs are subject to modulation by other TFs in a DNA region-specific manner. We also demonstrate that TF-TF relationships are often affected by alternative isoform usage and identify cooperativity and antagonism between human TFs and viral proteins from human papillomaviruses, Epstein-Barr virus, and other viruses. Altogether, pY1H assays provide a broadly applicable framework to study how different functional relationships affect protein occupancy at regulatory DNA regions.


Assuntos
Infecções por Vírus Epstein-Barr , Fatores de Transcrição , Humanos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Ligação Proteica , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/metabolismo , DNA/metabolismo , Sítios de Ligação
16.
Chem Biodivers ; 20(11): e202300602, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37798811

RESUMO

This study compared free and bound phenolic compounds in various marine microalgae species. It assessed total phenolic content (TPC), total flavonoid content (TFC) and total condensed tannin content (TCT) and their antioxidant capacities using 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS⋅+ ) radical cation-based assay and ferric ion reducing antioxidant power assay. Liquid chromatography-mass spectrometry (LC-MS) was also employed to characterize the phenolic profiling. Results showed that free phenolic compounds ranged from 1.83-6.45 mg GAE/g d. w., while bound phenolic compounds ranged from 4.03-26.03 mg GAE/g d. w., indicating significant differences. These variations were consistent across assays, highlining unique profiles in different species. A total 10 phenolics were found in these seven microalgae, including 1 phenolic acid, 6 flavonoids, 1 other polyphenol and 2 lignans. 4'-O-methyl-(-)-epigallocatechin 7-O-glucuronide and chrysoeriol 7-O-glucoside in microalgae were firstly reported in microalgal samples. These findings have implications for future applications in industries.


Assuntos
Antioxidantes , Microalgas , Antioxidantes/química , Flavonoides/química , Fenóis/química , Extratos Vegetais/química
17.
bioRxiv ; 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37645913

RESUMO

People with muco-obstructive pulmonary diseases such as cystic fibrosis (CF) and chronic obstructive pulmonary disease (COPD) often have acute or chronic respiratory infections that are difficult to treat due in part to the accumulation of hyperconcentrated mucus within the airway. Mucus accumulation and obstruction promote chronic inflammation and infection and reduce therapeutic efficacy. Bacterial aggregates in the form of biofilms exhibit increased resistance to mechanical stressors from the immune response (e.g., phagocytosis) and chemical treatments including antibiotics. Herein, combination treatments designed to disrupt the mechanical properties of biofilms and potentiate antibiotic efficacy are investigated against mucus-grown Pseudomonas aeruginosa biofilms and optimized to 1) alter biofilm viscoelastic properties, 2) increase mucociliary transport rates, and 3) reduce bacterial viability. A disulfide bond reducing agent (tris(2-carboxyethyl)phosphine, TCEP), a surfactant (NP40), a biopolymer (hyaluronic acid, HA), a DNA degradation enzyme (DNase), and an antibiotic (tobramycin) are tested in various combinations to maximize biofilm disruption. The viscoelastic properties of biofilms are quantified with particle tracking microrheology and transport rates are quantified in a mucociliary transport device comprised of fully differentiated primary human bronchial epithelial cells. The combination of the NP40 with hyaluronic acid and tobramycin was the most effective at increasing mucociliary transport rates, decreasing the viscoelastic properties of mucus, and reducing bacterial viability. Multimechanistic targeting of biofilm infections may ultimately result in improved clinical outcomes, and the results of this study may be translated into future in vivo infection models.

18.
Nucleic Acid Ther ; 33(5): 306-318, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37643307

RESUMO

Recent advances in the therapeutic potential of RNA-related treatments, specifically for antisense oligonucleotide (ASO)-based drugs, have led to increased numbers of ASO regulatory approvals. In this study, we focus on SPL84, an inhaled ASO-based drug, developed for the treatment of the pulmonary disease cystic fibrosis (CF). Pulmonary drug delivery is challenging, due to a variety of biological, physical, chemical, and structural barriers, especially when targeting the cell nucleus. The distribution of SPL84 throughout the lungs, penetration into the epithelial cells and nucleus, and structural stability are critical parameters that will impact drug efficacy in a clinical setting. In this study, we demonstrate broad distribution, as well as cell and nucleus penetration of SPL84 in mouse and monkey lungs. In vivo and in vitro studies confirmed the stability of our inhaled drug in CF patient-derived mucus and in lung lysosomal extracts. The mobility of SPL84 through hyperconcentrated mucus was also demonstrated. Our results, supported by a promising preclinical pharmacological effect of full restoration of cystic fibrosis transmembrane conductance regulator channel activity, emphasize the high potential of SPL84 as an effective drug for the treatment of CF patients. In addition, successfully tackling the lung distribution of SPL84 offers immense opportunities for further development of SpliSense's inhaled ASO-based drugs for unmet needs in pulmonary diseases.


Assuntos
Fibrose Cística , Humanos , Camundongos , Animais , Fibrose Cística/tratamento farmacológico , Fibrose Cística/genética , Oligonucleotídeos Antissenso/farmacologia , Preparações Farmacêuticas , Oligonucleotídeos/farmacologia , Oligonucleotídeos/uso terapêutico , Pulmão
19.
Front Physiol ; 14: 1233276, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37383143
20.
Cutis ; 111(1): E26-E30, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36947778

RESUMO

Fibroepithelioma of Pinkus (FeP) is a rare skin tumor with a clinical presentation similar to benign neoplasms such as acrochordons and seborrheic keratoses. Our study analyzed if there is an association between FeP and internal tumors, specifically gastrointestinal tract tumors. We retrospectively reviewed the medical records of patients with FeP for other tumors throughout their lives until 2020. Although the quality of documentation for each patient may have differed, this study suggests that the presence of FeP does not indicate the presence of gastrointestinal tract tumors, and there is no need for altered cancer screening recommendations for those with FeP.


Assuntos
Neoplasias Encefálicas , Carcinoma Basocelular , Neoplasias Fibroepiteliais , Neoplasias Cutâneas , Humanos , Estudos Retrospectivos , Neoplasias Fibroepiteliais/diagnóstico , Neoplasias Fibroepiteliais/patologia , Carcinoma Basocelular/patologia , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/patologia
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