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Ultraviolet (UV) light and incompletely understood genetic and epigenetic variations determine skin color. Here we describe an UV- and microphthalmia-associated transcription factor (MITF)-independent mechanism of skin pigmentation. Targeting the mitochondrial redox-regulating enzyme nicotinamide nucleotide transhydrogenase (NNT) resulted in cellular redox changes that affect tyrosinase degradation. These changes regulate melanosome maturation and, consequently, eumelanin levels and pigmentation. Topical application of small-molecule inhibitors yielded skin darkening in human skin, and mice with decreased NNT function displayed increased pigmentation. Additionally, genetic modification of NNT in zebrafish alters melanocytic pigmentation. Analysis of four diverse human cohorts revealed significant associations of skin color, tanning, and sun protection use with various single-nucleotide polymorphisms within NNT. NNT levels were independent of UVB irradiation and redox modulation. Individuals with postinflammatory hyperpigmentation or lentigines displayed decreased skin NNT levels, suggesting an NNT-driven, redox-dependent pigmentation mechanism that can be targeted with NNT-modifying topical drugs for medical and cosmetic purposes.
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Fator de Transcrição Associado à Microftalmia/metabolismo , NADP Trans-Hidrogenases/metabolismo , Pigmentação da Pele/efeitos da radiação , Raios Ultravioleta , Animais , Linhagem Celular , Estudos de Coortes , AMP Cíclico/metabolismo , Dano ao DNA , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Predisposição Genética para Doença , Humanos , Melanócitos/efeitos dos fármacos , Melanócitos/metabolismo , Melanossomas/efeitos dos fármacos , Melanossomas/metabolismo , Melanossomas/efeitos da radiação , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Monofenol Mono-Oxigenase/genética , Monofenol Mono-Oxigenase/metabolismo , NADP Trans-Hidrogenases/antagonistas & inibidores , Oxirredução/efeitos dos fármacos , Oxirredução/efeitos da radiação , Polimorfismo de Nucleotídeo Único/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise/efeitos dos fármacos , Proteólise/efeitos da radiação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Pigmentação da Pele/efeitos dos fármacos , Pigmentação da Pele/genética , Ubiquitina/metabolismo , Peixe-ZebraRESUMO
The physiological importance of cardiac myosin regulatory light chain (RLC) phosphorylation by its dedicated cardiac myosin light chain kinase has been established in both humans and mice. Constitutive RLC-phosphorylation, regulated by the balanced activities of cardiac myosin light chain kinase and myosin light chain phosphatase (MLCP), is fundamental to the biochemical and physiological properties of myofilaments. However, limited information is available on cardiac MLCP. In this study, we hypothesized that the striated muscle-specific MLCP regulatory subunit, MYPT2, targets the phosphatase catalytic subunit to cardiac myosin, contributing to the maintenance of cardiac function in vivo through the regulation of RLC-phosphorylation. To test this hypothesis, we generated a floxed-PPP1R12B mouse model crossed with a cardiac-specific Mer-Cre-Mer to conditionally ablate MYPT2 in adult cardiomyocytes. Immunofluorescence microscopy using the gene-ablated tissue as a control confirmed the localization of MYPT2 to regions where it overlaps with a subset of RLC. Biochemical analysis revealed an increase in RLC-phosphorylation in vivo. The loss of MYPT2 demonstrated significant protection against pressure overload-induced hypertrophy, as evidenced by heart weight, qPCR of hypertrophy-associated genes, measurements of myocyte diameters, and expression of ß-MHC protein. Furthermore, mantATP chase assays revealed an increased ratio of myosin heads distributed to the interfilament space in MYPT2-ablated heart muscle fibers, confirming that RLC-phosphorylation regulated by MLCP, enhances cardiac performance in vivo. Our findings establish MYPT2 as the regulatory subunit of cardiac MLCP, distinct from the ubiquitously expressed canonical smooth muscle MLCP. Targeting MYPT2 to increase cardiac RLC-phosphorylation in vivo may improve baseline cardiac performance, thereby attenuating pathological hypertrophy.
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Miócitos Cardíacos , Quinase de Cadeia Leve de Miosina , Animais , Humanos , Camundongos , Hipertrofia/metabolismo , Miócitos Cardíacos/metabolismo , Cadeias Leves de Miosina/genética , Cadeias Leves de Miosina/metabolismo , Quinase de Cadeia Leve de Miosina/genética , Quinase de Cadeia Leve de Miosina/metabolismo , Fosfatase de Miosina-de-Cadeia-Leve/metabolismo , Fosforilação , Camundongos Endogâmicos C57BLRESUMO
Microbes are found in nearly every habitat and organism on the planet, where they are critical to host health, fitness, and metabolism. In most organisms, few microbes are inherited at birth; instead, acquiring microbiomes generally involves complicated interactions between the environment, hosts, and symbionts. Despite the criticality of microbiome acquisition, we know little about where hosts' microbes reside when not in or on hosts of interest. Because microbes span a continuum ranging from generalists associating with multiple hosts and habitats to specialists with narrower host ranges, identifying potential sources of microbial diversity that can contribute to the microbiomes of unrelated hosts is a gap in our understanding of microbiome assembly. Microbial dispersal attenuates with distance, so identifying sources and sinks requires data from microbiomes that are contemporary and near enough for potential microbial transmission. Here, we characterize microbiomes across adjacent terrestrial and aquatic hosts and habitats throughout an entire watershed, showing that the most species-poor microbiomes are partial subsets of the most species-rich and that microbiomes of plants and animals are nested within those of their environments. Furthermore, we show that the host and habitat range of a microbe within a single ecosystem predicts its global distribution, a relationship with implications for global microbial assembly processes. Thus, the tendency for microbes to occupy multiple habitats and unrelated hosts enables persistent microbiomes, even when host populations are disjunct. Our whole-watershed census demonstrates how a nested distribution of microbes, following the trophic hierarchies of hosts, can shape microbial acquisition.
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Ecossistema , Microbiota , Plantas , Animais , Bactérias , Plantas/microbiologiaRESUMO
Research on mycorrhizal symbiosis has been slowed by a lack of established study systems. To address this challenge, we have been developing Suillus, a widespread ecologically and economically relevant fungal genus primarily associated with the plant family Pinaceae, into a model system for studying ectomycorrhizal (ECM) associations. Over the last decade, we have compiled extensive genomic resources, culture libraries, a phenotype database, and protocols for manipulating Suillus fungi with and without their tree partners. Our efforts have already resulted in a large number of publicly available genomes, transcriptomes, and respective annotations, as well as advances in our understanding of mycorrhizal partner specificity and host communication, fungal and plant nutrition, environmental adaptation, soil nutrient cycling, interspecific competition, and biological invasions. Here, we highlight the most significant recent findings enabled by Suillus, present a suite of protocols for working with the genus, and discuss how Suillus is emerging as an important model to elucidate the ecology and evolution of ECM interactions.
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Evolução Biológica , Modelos Biológicos , Micorrizas , Micorrizas/fisiologia , Micorrizas/genética , Ecologia , Simbiose/genética , Basidiomycota/fisiologia , Basidiomycota/genéticaRESUMO
Severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) is the causative pathogen of coronavirus disease-19 (COVID-19). The COVID-19 pandemic has resulted in millions of deaths and widespread socio-economic damage worldwide. Therefore, numerous studies have been conducted to identify effective measures to control the spreading of the virus. Among various potential targets, the 3 chymotrypsin-like protease (3CLpro), also known as Mpro, stands out as the key protease of SARS-CoV-2, playing an essential role in virus replication and assembly, is the most prospective. In this study, we modified the commercial vector, pETM33-Nsp5-Mpro (plasmid # 156475, Addgene, USA), by inserting an autocleavage site (AVLQ) of 3CLpro and 6 × His-tag encoding sequences before and after the Nsp5-Mpro sequence, respectively. This modification enabled the expression of 3CLpro as an authentic N terminal protease (au3CLpro), which was purified to electrophoretic homogeneity by a single-step chromatography using two tandem Glutathione- and Ni-Sepharose columns. The enzyme au3CLpro demonstrated significantly higher activity (3169 RFU/min/µg protein) and catalytic efficiency (Kcat/Km of 0.007 µM-1.s-1) than that of the 3CLpro (com3CLpro) expressed from the commercial vector (pETM33-Nsp5-Mpro) with specific activity 889 RFU/min/µg and Kcat/Km of 0.0015 µM-1.s-1, respectively. Optimal conditions for au3CLpro activity included a 50 mM Tris-HCl buffer at pH 7, containing 150 mM NaCl and 0.1 mg/ml BSA at 37 °C.
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COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Quimases , Pandemias , Estudos Prospectivos , Peptídeo Hidrolases/metabolismo , Inibidores de Proteases , Antivirais/uso terapêutico , Simulação de Acoplamento MolecularRESUMO
CRISPR-Cas genome-editing nucleases hold substantial promise for developing human therapeutic applications1-6 but identifying unwanted off-target mutations is important for clinical translation7. A well-validated method that can reliably identify off-targets in vivo has not been described to date, which means it is currently unclear whether and how frequently these mutations occur. Here we describe 'verification of in vivo off-targets' (VIVO), a highly sensitive strategy that can robustly identify the genome-wide off-target effects of CRISPR-Cas nucleases in vivo. We use VIVO and a guide RNA deliberately designed to be promiscuous to show that CRISPR-Cas nucleases can induce substantial off-target mutations in mouse livers in vivo. More importantly, we also use VIVO to show that appropriately designed guide RNAs can direct efficient in vivo editing in mouse livers with no detectable off-target mutations. VIVO provides a general strategy for defining and quantifying the off-target effects of gene-editing nucleases in whole organisms, thereby providing a blueprint to foster the development of therapeutic strategies that use in vivo gene editing.
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Proteínas Associadas a CRISPR/metabolismo , Sistemas CRISPR-Cas/genética , Edição de Genes/métodos , Edição de Genes/normas , Genoma/genética , Mutação , Especificidade por Substrato/genética , Animais , Proteínas Associadas a CRISPR/genética , Feminino , Humanos , Mutação INDEL , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pró-Proteína Convertase 9/genética , Transgenes/genéticaRESUMO
While durian shell is often discharged into landfills, this waste can be a potential and zero-cost raw material to synthesize carbon-based adsorbents with purposes of saving costs and minimizing environmental contamination. Indole (IDO) is one of serious organic pollutants that influence aquatic species and human health; hence, the necessity for IDO removal is worth considering. Here, we synthesized a magnetic composite, denoted as MFOAC, based on activated carbon (AC) derived from durian shell waste incorporated with MnFe2O4 (MFO) to adsorb IDO in water. MFOAC showed a microporous structure, along with a high surface area and pore volume, at 518.9 m2/g, and 0.106 cm3/g, respectively. Optimization of factors affecting the IDO removal of MFOAC were implemented by Box-Behnken design and response surface methodology. Adsorption kinetics and isotherms suggested a suitable model for MFOAC to remove IDO. MFOAC was recyclable with 3 cycles. Main interactions involving in the IDO adsorption mechanism onto MFOAC were clarified, including pore filling, n-π interaction, π-π interaction, Yoshida H-bonding, H-bonding.
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Carvão Vegetal , Compostos Férricos , Indóis , Compostos de Manganês , Poluentes Químicos da Água , Indóis/química , Poluentes Químicos da Água/química , Adsorção , Compostos de Manganês/química , Compostos Férricos/química , Carvão Vegetal/química , Animais , Purificação da Água/métodosRESUMO
By applying the hybrid molecular strategy, in this study, we reported the synthesis of fifteen quinolin-2-one hydrazones containing nitrophenyl or nicotinonyl/isonicotinoyl moiety, followed by in vitro and in silico evaluations of their potential antimicrobial and anticancer activities. In vitro antimicrobial evaluation of the target compounds on seven pathogenic strains, applying the broth microdilution method, revealed that compound 4a demonstrated the most potential antifungal activity against C. albicans (MIC 512 µg.mL-1) and C. krusei (MIC 128 µg.mL-1). In vitro cytotoxic evaluation of the target compounds on three human cancer cell lines, employing the MTT method, suggested that compound 5c exhibited the most potential cytotoxicities against HepG2 (IC50 10.19 µM), A549 (IC50 20.43 µM), and MDA-MB-231 (IC50 16.82 µM) cells. Additionally, molecular docking studies were performed to investigate the binding characteristics of compounds 4a and 5c with fungal lanosterol 14α-demethylase and human topoisomerase I-II, respectively, thereby contributing to the elucidation of their in vitro antifungal and cytotoxic properties. Furthermore, compounds 4a and 5c, via SwissADME prediction, could exhibit favorable physicochemical and pharmacokinetic properties. In conclusion, this study provides valuable insights into the potential of quinolin-2-one hydrazones as promising candidates for the development of novel antimicrobial and anticancer agents in the future.
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BACKGROUND: Kombucha is a widely consumed fermented beverage produced by fermenting sweet tea with a symbiotic culture of bacteria and yeast (SCOBY). The dynamic nature of microbial communities in SCOBY may pose challenges to production scale-up due to unpredictable variations in microbial composition. Using identified starter strains is a novel strategy to control microorganism composition, thereby ensuring uniform fermentation quality across diverse batches. However, challenges persist in the cultivation and maintenance of these microbial strains. This study examined the potential of microencapsulated kombucha fermentation starter cultures, specifically Komagataeibacter saccharivorans, Levilactobacillus brevis and Saccharomyces cerevisiae, through spray-drying and freeze-drying. RESULTS: Maltodextrin and gum arabic-maltodextrin were employed as carrier agents. Our results revealed that both spray-dried and freeze-dried samples adhered to physicochemical criteria, with low moisture content (2.18-7.75%) and relatively high solubility (65.75-87.03%) which are appropriate for food application. Freeze-drying demonstrated greater effectiveness in preserving bacterial strain viability (88.30-90.21%) compared to spray drying (74.92-78.66%). Additionally, the freeze-dried starter strains demonstrated similar efficacy in facilitating kombucha fermentation, compared to the SCOBY group. The observations included pH reduction, acetic acid production, α-amylase inhibition and elevated total polyphenol and flavonoid content. Moreover, the biological activity, including antioxidant potential and in vitro tyrosinase inhibition activity, was enhanced in the same pattern. The freeze-dried strains exhibited consistent kombucha fermentation capabilities over a three-month preservation, regardless of storage temperature at 30 or 4 °C. CONCLUSION: These findings highlight the suitability of freeze-dried starter cultures for kombucha production, enable microbial composition control, mitigate contamination risks and ensure consistent product quality. © 2024 Society of Chemical Industry.
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Cardiac muscle myosin regulatory light chain (RLC) is constitutively phosphorylated at â¼0.4 mol phosphate/mol RLC in normal hearts, and phosphorylation is maintained by balanced activities of dedicated cardiac muscle-specific myosin light chain kinase and myosin light chain phosphatase (MLCP). Previously, the identity of the cardiac-MLCP was biochemically shown to be similar to the smooth muscle MLCP, which is a well-characterized trimeric protein comprising the regulatory subunit (MYPT1), catalytic subunit PP1cß, and accessory subunit M20. In smooth muscles in vivo, MYPT1 and PP1cß co-stabilize each other and are both necessary for normal smooth muscle contractions. In the cardiac muscle, MYPT1 and MYPT2 are both expressed, but contributions to physiological regulation of cardiac myosin dephosphorylation are unclear. We hypothesized that the main catalytic subunit for cardiac-MLCP is PP1cß, and maintenance of RLC phosphorylation in vivo is dependent on regulation by striated muscle-specific MYPT2. Here, we used PP1cß conditional knockout mice to biochemically define cardiac-MLCP proteins and developed a cardiac myofibrillar phosphatase assay to measure the direct contribution of MYPT-regulated and MYPT-independent phosphatase activities toward phosphorylated cardiac myosin. We report that (1) PP1cß is the main isoform expressed in the cardiac myocyte, (2) cardiac muscle pathogenesis in PP1cß knockout animals involve upregulation of total PP1cα in myocytes and non-muscle cells, (3) the stability of cardiac MYPT1 and MYPT2 proteins in vivo is not dependent on the PP1cß expression, and (4) phosphorylated myofibrillar cardiac myosin is dephosphorylated by both myosin-targeted and soluble MYPT-independent PP1cß activities. These results contribute to our understanding of the cardiac-MLCP in vivo.
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Miosinas Cardíacas , Fosfatase de Miosina-de-Cadeia-Leve , Proteína Fosfatase 1 , Animais , Miosinas Cardíacas/metabolismo , Camundongos , Camundongos Knockout , Fosfatase de Miosina-de-Cadeia-Leve/metabolismo , Fosfatos/metabolismo , Fosforilação , Proteína Fosfatase 1/genética , Proteína Fosfatase 1/metabolismoRESUMO
BACKGROUND: Cancers of the head and neck region are often characterized by locally advanced, non-metastatic disease. Standard treatments for advanced cervico-facial cancers of the skin or primary head and neck squamous cell carcinoma (HNSCC) include combinations of surgery, radiation and chemotherapy, which are associated with high rates of acute toxicity and complications. Stereotactic body radiotherapy (SBRT) has been shown to be a promising modality of treatment for this patient population in retrospective studies; to our knowledge, there are no prospective clinical studies evaluating the safety and efficacy of SBRT in these patients. METHODS: This phase 2, single institution, single arm study aims to evaluate response rates to SBRT in older age patients with locally advanced HNSCC for whom primary surgery is not recommended or performed. The intervention is SBRT 45 Gy in 5 fractions given every 3-4 days. Toxicity, quality of life and patient outcomes will be recorded regularly up to 24 months after completion of SBRT. DISCUSSION: For this patient population, SBRT may offer a shorter and more effective treatment than the current standard of care palliative regimens. If the study demonstrates that SBRT is safe and effective, then this may lead to randomized studies comparing conventional radiotherapy to SBRT for selected head and neck cancer patients. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04435938 . Date registered: June 17, 2020.
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Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Radiocirurgia , Humanos , Carcinoma de Células Escamosas/patologia , Ensaios Clínicos Fase II como Assunto , Neoplasias de Cabeça e Pescoço/radioterapia , Qualidade de Vida , Radiocirurgia/efeitos adversos , Radiocirurgia/métodos , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço/radioterapiaRESUMO
BACKGROUND: Traffic-related air pollution (TRAP) problems are unlikely to be solved in the short term, making it imperative to educate children on protective measures to mitigate the negative impact on their health. Children and their caregivers may hold differing views on wearing a face mask as a safeguard against air pollution. While many studies have focused on predicting children's health-protective behaviours against air pollution, few have explored the differences in perceptions between children and their caregivers. OBJECTIVES: To examine this, we conducted a study that compared the health beliefs of two generations and evaluated the factors that influence the use of masks by children to reduce air pollution exposure. METHODS: The study was conducted in 24 secondary schools and involved 8420 children aged 13-14 and their caregivers. We used a Health Belief Model (HBM)-based instrument containing 17-item self-administered health beliefs questionnaires to gather data. The results were analysed using hierarchical logistic regression to determine the probability of children frequently wearing masks to protect against TRAP. RESULTS: Our study showed both children and caregivers recognised that several factors could influence mask-wearing among children: discomfort or difficulty breathing while wearing a mask and forgetting to bring a mask when going outside; perceived threats of the poor quality of air and children's respiratory health problems; and cues to mask use (i.e., seeing most of their friends wearing facemasks and ease of finding masks in local stores). However, only children were significantly concerned with public perception of their appearance while wearing a mask. Females were more likely to wear masks, and caregivers with higher levels of education were more likely to encourage their children to wear masks. Children who commuted to schools by walking, biking, or motorbiking were also more accepting of mask-wearing than those who travelled by car or bus. CONCLUSIONS: Children and their caregivers hold different perceptions of wearing masks to protect against air pollution. Children are more susceptible to social judgements regarding their appearance when wearing a mask.
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Poluição do Ar , Cuidadores , Feminino , Humanos , Criança , Vietnã , Instituições Acadêmicas , Saúde da CriançaRESUMO
OBJECTIVE: Lack of recognition of asthma in childhood results in unmet asthma treatment needs and leads to the risk of sub-optimal respiratory health. The present study assessed the prevalence of asthmatic under-recognition in middle school children in Vietnam. METHODS: We conducted a school-based survey among 15,112 Vietnamese children. Most of them are aged from 13 to 14. Schools and students were recruited using multi-stage sampling. Respiratory symptoms were collected via self-report using a standardized tool from the International Study of Asthma and Allergies in Childhood. Under-recognition of asthma was defined as a presence of at least one asthma-like symptom but a negative response to having ever asthma. Associations were investigated using logistic regression. RESULTS: Prevalence of asthma-like symptoms was 27.3% and prevalence of physician-diagnosed asthma was 8.5%. Over 80% of symptomatic children were not diagnosed with asthma. Under-recognition of asthma was found more in girls (adjusted odds ratio; aOR = 1.75; 95%CI: 1.54 to 1.98). CONCLUSIONS: Asthma is significantly under-recognized in Vietnamese middle-school children. Urgent action is required to improve the recognition of asthma in Vietnam.
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Asma , Criança , Feminino , Humanos , Masculino , Asma/diagnóstico , Asma/epidemiologia , Prevalência , População do Sudeste Asiático , Estudantes , Inquéritos e Questionários , Vietnã/epidemiologia , AdolescenteRESUMO
MnO2 nanoparticles have played a vital role in biomedical, catalysis, electrochemical and energy storage fields, but requiring toxic chemicals in the fabrication intercepts their applications. There is an increasing demand for biosynthesis of MnO2 nanoparticles using green sources such as plant species in accordance with the purposes of environmental mitigation and production cost reduction. Here, we review recent advancements on the use of natural compounds such as polyphenols, reducing sugars, quercetins, etc. Extracted directly from low-cost and available plants for biogenic synthesis of MnO2 nanoparticles. Role of these phytochemicals and formation mechanism of bio-medicated MnO2 nanoparticles are shed light on. MnO2 nanoparticles own small particle size, high crystallinity, diverse morphology, high surface area and stability. Thanks to higher biocompatibility, bio-mediated synthesized MnO2 nanoparticles exhibited better antibacterial, antifungal, and anticancer activity than chemically synthesized ones. In terms of wastewater treatment and energy storage, they also served as efficient adsorbents and catalyst. Moreover, several aspects of limitation and future outlook of bio-mediated MnO2 nanoparticles in the fields are analyzed. It is expected that the present work not only expands systematic understandings of synthesis methods, properties and applications MnO2 nanoparticles but also pave the way for the nanotechnology revolution in combination with green chemistry and sustainable development.
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Nanopartículas Metálicas , Nanopartículas , Compostos de Manganês/química , Óxidos/química , Química Verde , Nanopartículas/química , Nanotecnologia/métodos , Plantas , Nanopartículas Metálicas/químicaRESUMO
Regulation of quiescence is critical for the maintenance of adult hematopoietic stem cells (HSCs). Disruption of transcription factor gene Prdm16 during mouse embryonic development has been shown to cause a severe loss of fetal liver HSCs; however, the underlying mechanisms and the function of Prdm16 in adult HSCs remain unclear. To investigate the role of Prdm16 in adult HSCs, we generated a novel conditional knockout mouse model and deleted Prdm16 in adult mouse hematopoietic system using the IFN-inducible Mx1-Cre Our results show that Prdm16 deletion in the adult mouse hematopoietic system has a less severe effect on HSCs, causing a gradual decline of adult HSC numbers and a concomitant increase in the multipotent progenitor (MPP) compartment. Prdm16 deletion in the hematopoietic system following transplantation produced the same phenotype, indicating that the defect is intrinsic to adult HSCs. This HSC loss was also exacerbated by stress induced by 5-fluorouracil injections. Annexin V staining showed no difference in apoptosis between wild-type and knockout adult HSCs. In contrast, Bromodeoxyuridine analysis revealed that loss of Prdm16 significantly increased cycling of long-term HSCs (LT-HSCs) with the majority of the cells found in the S to G2/M phase. Consistently, RNA sequencing analysis of mouse LT-HSCs with and without Prdm16 deletion showed that Prdm16 loss induced a significant decrease in the expression of several known cell cycle regulators of HSCs, among which Cdkn1a and Egr1 were identified as direct targets of Prdm16 Our results suggest that Prdm16 preserves the function of adult LT-HSCs by promoting their quiescence.
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Células-Tronco Adultas/fisiologia , Ciclo Celular/genética , Proteínas de Ligação a DNA/metabolismo , Células-Tronco Hematopoéticas/fisiologia , Fatores de Transcrição/metabolismo , Ativação Transcricional , Animais , Inibidor de Quinase Dependente de Ciclina p21/genética , Proteínas de Ligação a DNA/genética , Proteína 1 de Resposta de Crescimento Precoce/genética , Feminino , Transplante de Células-Tronco Hematopoéticas , Camundongos , Camundongos Knockout , RNA-Seq , Fatores de Transcrição/genéticaRESUMO
Cardiovascular involvement has been described in acute and recovered COVID-19 patients. Here, we present a case of symptomatic pericarditis with persistent symptoms for at least six months after the acute infection and report 66 published cases of pericarditis in discharged COVID patients. Patient mean age ± SD was 49.7 ± 13.3 years, ranging from 15 to 75 years and 57.6% were female. A proportion of 89.4% patients reported at least one comorbidity, with autoimmune and allergic disorders, hypertension and dyslipidaemia, as the most frequent. Only 8.3% of patients experienced severe symptoms of acute COVID-19. The time between acute COVID and pericarditis symptoms varied from 14 to 255 days. Chest pain (90.9%), tachycardia (60.0%) and dyspnoea (38.2%) were the most frequent symptoms in post-acute pericarditis. A proportion of 45.5% and 87% of patients had an abnormal electrocardiogram and abnormal transthoracic ultrasound, respectively. Colchicine combined with non-steroidal anti-inflammatory drug (NSAID) or acetylsalicylic acid (aspirin) were prescribed to 39/54 (72%) patients. Of them, 12 were switched to corticosteroid therapy due to non-response to the first-line treatment. Only 6 patients had persisting symptoms and were considered as non-respondent to therapy.Our report highlights that pericarditis should be suspected in COVID-19 patients with persistent chest pain and dyspnoea when pulmonary function is normal. Treatment with non-steroidal anti-inflammatory and colchicine is usually effective but corticosteroids are sometimes required.
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COVID-19 , Pericardite , Humanos , Feminino , Masculino , COVID-19/complicações , Anti-Inflamatórios não Esteroides/uso terapêutico , Pericardite/diagnóstico , Pericardite/tratamento farmacológico , Pericardite/etiologia , Aspirina/uso terapêutico , Colchicina/uso terapêutico , Dor no Peito/complicações , Dor no Peito/tratamento farmacológicoRESUMO
In 2017, Global Initiative for Chronic Lung Disease (GOLD) made substantial changes to its ABCD group categorization. Although several studies had been conducted to assess the impact of the new GOLD category, there was no research on the change of the GOLD classification in Vietnam. This retrospective analysis was conducted at Asthma and COPD clinic at the University Medical Center in Ho Chi Minh City, Vietnam. Our study population comprised patients visiting Medical Center from January 2018 to January 2020. We categorized patients' demographic, clinical characteristics and pharmacotherapy based on GOLD 2011 and 2017 guidelines. A comparison between the two versions was also determined. A total of 457 patients were included in this study. The percentage of groups A, B, C and D according to GOLD 2011 was 5%, 20.8%, 13.1% and 61.1%; and according to GOLD 2017 was 6.1%, 34.1%, 12% and 47.8%, respectively. In terms of gender, male patients constituted nearly 95% of the study's population (433/457 patients). Regarding pharmacotherapy, approximately 20% of the low-risk group (group A-B) was overtreated with ICS components: LABA+ICS (15.8%) and LAMA+LABA+ICS (3.8%). There were 13.3% and 1.1% of patients transferred from D to B and from C to A, respectively. All of them had lower FVC% pred, FEV1% pred and FEV1/FVC than the patients remained in group B or A (p<0.005). This is the first research in Vietnam to show the distribution of COPD patients using both the GOLD 2011 and GOLD 2017 criteria. There was 14% of patients reclassified from high-risk groups to low-risk groups when changing from 2011 to 2017 version and discordance of medications between guidelines and real-life practice. Therefore, clinicians should use their clinical competence to consider patients' conditions before deciding the appropriate therapeutic approach. Consequently, further studies were required to evaluate the effect of the change in GOLD classification.
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We describe 188 patients in France who were successively infected with different SARS-CoV-2 Omicron subvariants, including BA.1, BA.2, and BA.5. Time between 2 infections was <90 days for 50 (26.6%) patients and <60 days for 28 (14.9%) patients. This finding suggests that definitions for SARS-CoV-2 reinfection require revision.
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COVID-19 , Reinfecção , Humanos , SARS-CoV-2 , França/epidemiologiaRESUMO
Sequence control in synthetic copolymers remains a tantalizing objective in polymer science due to the influence of sequence on material properties and self-organization. A greater understanding of sequence development throughout the polymerization process will aid the design of simple, generalizable methods to control sequence and tune supramolecular assembly. In previous simulations of solution-based step-growth copolymerizations, we have shown that weak, non-bonding attractions between monomers of the same type can produce a microphase separation among the lengthening nascent oligomers and thereby alter sequence. This work explores the phenomenon further, examining how effective attractive interactions, mediated by a solvent selective for one of the reacting species, impact the development of sequence and the supramolecular assembly in a simple A-B copolymerization. We find that as the effective attractions between monomers increase, an emergent self-organization of the reactants causes a shift in reaction kinetics and sequence development. When the solvent-mediated interactions are selective enough, the simple mixture of A and B monomers oligomerize and self-assemble into structures characteristic of amphiphilic copolymers. The composition and morphology of these structures and the sequences of their chains are sensitive to the relative balance of affinities between the comonomer species. Our results demonstrate the impact of differing A-B monomer-solvent affinities on sequence development in solution-based copolymerizations and are of consequence to the informed design of synthetic methods for sequence controlled amphiphilic copolymers and their aggregates.
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BACKGROUND: Long COVID-19 may affect patients after hospital discharge. AIMS: This study aims to describe the burden of the long-term persistence of clinical symptoms in COVID-19 patients. METHODS: We conducted a systematic review by using the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guideline. The PubMed and Google Scholar databases were searched for studies that included information on the prevalence of somatic clinical symptoms lasting at least 4 weeks after the onset of a PCR- or serology-confirmed diagnosis of COVID-19. The prevalence of persisting clinical symptoms was assessed and risk factors were described when investigated. Psychological symptoms and cognitive disorders were not evaluated in this study. RESULTS: Thirty-seven articles met the inclusion criteria. Eighteen studies involved in-patients only with a duration of follow-up of either less than 12 weeks, 12 weeks to 6 months, or more. In these studies, fatigue (16-64%), dyspnea (15-61%), cough (2-59%), arthralgia (8-55%), and thoracic pain (5-62%) were the most frequent persisting symptoms. In nineteen studies conducted in a majority of out-patients, the persistence of these symptoms was lower and 3% to 74% of patients reported prolonged smell and taste disorders. The main risk factors for persisting symptoms were being female, older, having comorbidities and severity at the acute phase of the disease. CONCLUSION: COVID-19 patients should have access to dedicated multidisciplinary healthcare allowing a holistic approach. Effective outpatient care for patients with long-COVID-19 requires coordination across multiple sub-specialties, which can be proposed in specialized post-COVID units.