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Of all known cultured stem cell types, pluripotent stem cells (PSCs) sit atop the landscape of developmental potency and are characterized by their ability to generate all cell types of an adult organism. However, PSCs show limited contribution to the extraembryonic placental tissues in vivo. Here, we show that a chemical cocktail enables the derivation of stem cells with unique functional and molecular features from mice and humans, designated as extended pluripotent stem (EPS) cells, which are capable of chimerizing both embryonic and extraembryonic tissues. Notably, a single mouse EPS cell shows widespread chimeric contribution to both embryonic and extraembryonic lineages in vivo and permits generating single-EPS-cell-derived mice by tetraploid complementation. Furthermore, human EPS cells exhibit interspecies chimeric competency in mouse conceptuses. Our findings constitute a first step toward capturing pluripotent stem cells with extraembryonic developmental potentials in culture and open new avenues for basic and translational research. VIDEO ABSTRACT.
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Técnicas de Cultura de Células/métodos , Células-Tronco Pluripotentes/citologia , Animais , Blastocisto/citologia , Linhagem Celular , Quimera/metabolismo , Dimetideno/farmacologia , Humanos , Indicadores e Reagentes/química , Camundongos , Minociclina/química , Minociclina/farmacologia , Células-Tronco Pluripotentes/efeitos dos fármacos , Poli(ADP-Ribose) Polimerase-1/metabolismoRESUMO
A fundamental and unresolved question in regenerative biology is how tissues return to homeostasis after injury. Answering this question is essential for understanding the aetiology of chronic disorders such as inflammatory bowel diseases and cancer1. We used the Drosophila midgut2 to investigate this and discovered that during regeneration a subpopulation of cholinergic3 neurons triggers Ca2+ currents among intestinal epithelial cells, the enterocytes, to promote return to homeostasis. We found that downregulation of the conserved cholinergic enzyme acetylcholinesterase4 in the gut epithelium enables acetylcholine from specific Egr5 (TNF in mammals)-sensing cholinergic neurons to activate nicotinic receptors in innervated enterocytes. This activation triggers high Ca2+, which spreads in the epithelium through Innexin2-Innexin7 gap junctions6, promoting enterocyte maturation followed by reduction of proliferation and inflammation. Disrupting this process causes chronic injury consisting of ion imbalance, Yki (YAP in humans) activation7, cell death and increase of inflammatory cytokines reminiscent of inflammatory bowel diseases8. Altogether, the conserved cholinergic pathway facilitates epithelial Ca2+ currents that heal the intestinal epithelium. Our findings demonstrate nerve- and bioelectric9-dependent intestinal regeneration and advance our current understanding of how a tissue returns to homeostasis after injury.
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Sinalização do Cálcio , Cálcio , Neurônios Colinérgicos , Drosophila melanogaster , Enterócitos , Intestinos , Animais , Humanos , Acetilcolina/metabolismo , Acetilcolinesterase/metabolismo , Cálcio/metabolismo , Neurônios Colinérgicos/metabolismo , Drosophila melanogaster/enzimologia , Drosophila melanogaster/metabolismo , Enterócitos/metabolismo , Homeostase , Inflamação/enzimologia , Inflamação/metabolismo , Doenças Inflamatórias Intestinais/metabolismo , Intestinos/citologia , Intestinos/metabolismo , Receptores Nicotínicos/metabolismo , Modelos Animais de DoençasRESUMO
Recent developments of sequencing-based spatial transcriptomics (sST) have catalyzed important advancements by facilitating transcriptome-scale spatial gene expression measurement. Despite this progress, efforts to comprehensively benchmark different platforms are currently lacking. The extant variability across technologies and datasets poses challenges in formulating standardized evaluation metrics. In this study, we established a collection of reference tissues and regions characterized by well-defined histological architectures, and used them to generate data to compare 11 sST methods. We highlighted molecular diffusion as a variable parameter across different methods and tissues, significantly affecting the effective resolutions. Furthermore, we observed that spatial transcriptomic data demonstrate unique attributes beyond merely adding a spatial axis to single-cell data, including an enhanced ability to capture patterned rare cell states along with specific markers, albeit being influenced by multiple factors including sequencing depth and resolution. Our study assists biologists in sST platform selection, and helps foster a consensus on evaluation standards and establish a framework for future benchmarking efforts that can be used as a gold standard for the development and benchmarking of computational tools for spatial transcriptomic analysis.
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Recent advances in single-cell sequencing provide a unique opportunity to gain novel insights into the diversity, lineage, and functions of cell types constituting a tissue/organ. Here, we performed a single-nucleus study of the adult Drosophila renal system, consisting of Malpighian tubules and nephrocytes, which shares similarities with the mammalian kidney. We identified 11 distinct clusters representing renal stem cells, stellate cells, regionally specific principal cells, garland nephrocyte cells, and pericardial nephrocytes. Characterization of the transcription factors specific to each cluster identified fruitless (fru) as playing a role in stem cell regeneration and Hepatocyte nuclear factor 4 (Hnf4) in regulating glycogen and triglyceride metabolism. In addition, we identified a number of genes, including Rho guanine nucleotide exchange factor at 64C (RhoGEF64c), Frequenin 2 (Frq2), Prip, and CG1093 that are involved in regulating the unusual star shape of stellate cells. Importantly, the single-nucleus dataset allows visualization of the expression at the organ level of genes involved in ion transport and junctional permeability, providing a systems-level view of the organization and physiological roles of the tubules. Finally, a cross-species analysis allowed us to match the fly kidney cell types to mouse kidney cell types and planarian protonephridia, knowledge that will help the generation of kidney disease models. Altogether, our study provides a comprehensive resource for studying the fly kidney.
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Proteínas de Drosophila , Drosophila melanogaster , Fator 4 Nuclear de Hepatócito , Túbulos de Malpighi , Proteínas do Tecido Nervoso , Fatores de Transcrição , Animais , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Fator 4 Nuclear de Hepatócito/genética , Rim/citologia , Rim/fisiologia , Túbulos de Malpighi/citologia , Túbulos de Malpighi/fisiologia , Camundongos , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Regeneração , Análise de Sequência de RNA/métodos , Análise de Célula Única , Células-Tronco/metabolismo , Células-Tronco/fisiologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
Alkaloids are a large group of plant secondary metabolites with various structures and activities. It is important to understand their functions in the interplay between plants and the beneficial and pathogenic microbiota. Amaryllidaceae alkaloids (AAs) are unique secondary metabolites in Amaryllidaceae plants. Here, we studied the interplay between AAs and the bacteriome in Lycoris radiata, a traditional Chinese medicinal plant containing high amounts of AAs. The relationship between AAs and bacterial composition in different tissues of L. radiata was studied. In vitro experiments revealed that AAs have varying levels of antimicrobial activity against endophytic bacteria and pathogenic fungi, indicating the importance of AA synthesis in maintaining a balance between plants and beneficial/pathogenic microbiota. Using bacterial synthetic communities with different compositions, we observed a positive feedback loop between bacteria insensitive to AAs and their ability to increase accumulation of AAs in L. radiata, especially in leaves. This may allow insensitive bacteria to outcompete sensitive ones for plant resources. Moreover, the accumulation of AAs enhanced by insensitive bacteria could benefit plants when challenged with fungal pathogens. This study highlights the functions of alkaloids in plant-microbe interactions, opening new avenues for designing plant microbiomes that could contribute to sustainable agriculture.
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Alcaloides , Alcaloides de Amaryllidaceae , Lycoris , Alcaloides de Amaryllidaceae/farmacologia , Alcaloides de Amaryllidaceae/química , Alcaloides de Amaryllidaceae/metabolismo , Lycoris/química , Lycoris/metabolismo , Alcaloides/metabolismo , Extratos Vegetais/químicaRESUMO
Bone consists of separate inner endosteal and outer periosteal compartments, each with distinct contributions to bone physiology and each maintaining separate pools of cells owing to physical separation by the bone cortex. The skeletal stem cell that gives rise to endosteal osteoblasts has been extensively studied; however, the identity of periosteal stem cells remains unclear1-5. Here we identify a periosteal stem cell (PSC) that is present in the long bones and calvarium of mice, displays clonal multipotency and self-renewal, and sits at the apex of a differentiation hierarchy. Single-cell and bulk transcriptional profiling show that PSCs display transcriptional signatures that are distinct from those of other skeletal stem cells and mature mesenchymal cells. Whereas other skeletal stem cells form bone via an initial cartilage template using the endochondral pathway4, PSCs form bone via a direct intramembranous route, providing a cellular basis for the divergence between intramembranous versus endochondral developmental pathways. However, there is plasticity in this division, as PSCs acquire endochondral bone formation capacity in response to injury. Genetic blockade of the ability of PSCs to give rise to bone-forming osteoblasts results in selective impairments in cortical bone architecture and defects in fracture healing. A cell analogous to mouse PSCs is present in the human periosteum, raising the possibility that PSCs are attractive targets for drug and cellular therapy for skeletal disorders. The identification of PSCs provides evidence that bone contains multiple pools of stem cells, each with distinct physiologic functions.
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Desenvolvimento Ósseo , Osso e Ossos/citologia , Periósteo/citologia , Células-Tronco/citologia , Animais , Catepsina K/metabolismo , Diferenciação Celular , Feminino , Fêmur/citologia , Consolidação da Fratura , Regulação da Expressão Gênica , Humanos , Masculino , Células-Tronco Mesenquimais/citologia , Camundongos , Osteoblastos/citologia , Crânio/citologiaRESUMO
INTRODUCTION: Community General Practitioners (CGPs) are crucial to primary healthcare worldwide. Their job satisfaction significantly impacts the quality and accessibility of healthcare. However, a comprehensive global perspective on this issue remains absent, necessitating this systematic review and meta-analysis. METHODS: This systematic review and meta-analysis sourced literature from PubMed, Web of Science, CNKI, and Wanfang, up to June 14, 2023. Of the 2,742 identified studies, 100 articles were selected for meta-analysis to assess satisfaction levels, and 97 studies were chosen for comparative analysis of influential factors. We employed both meta-analytic and comparative analytic methodologies, focusing on varying geographical, economic, and temporal contexts. RESULTS: The pooled rate and corresponding 95% confidence interval (CI) for job satisfaction among CGPs was 70.82% (95%CI: 66.62-75.02%) globally. Studies utilizing 5-point score scale obtained a random effect size of 3.52 (95%CI: 3.43-3.61). Diverse factors influenced satisfaction, with remuneration and working conditions being predominant. A noticeable decline in job satisfaction has been observed since the coronavirus disease 2019 outbreak, with satisfaction rates dropping from an average of 72.39% before 2009 to 63.09% in those published after 2020. CONCLUSIONS: The downward trend in CGPs' job satisfaction is concerning and warrants urgent attention from policymakers, especially in regions with an acute shortage of CGPs. The findings from this comprehensive review and meta-analysis provide essential insights for informed healthcare policy-making. It highlights the urgency of implementing strategies to enhance CGP satisfaction, thereby improving the effectiveness of primary healthcare systems globally.
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COVID-19 , Clínicos Gerais , Satisfação no Emprego , Humanos , Clínicos Gerais/psicologia , COVID-19/epidemiologia , COVID-19/psicologia , Atenção Primária à Saúde , SARS-CoV-2 , Saúde GlobalRESUMO
BACKGROUND: A global plan has been set to end human deaths from dog-mediated rabies by 2030 ("Zero-by-30"), but whether it could be achieved in some countries, such as China, remains unclear. Although elimination strategies through post-exposure prophylaxis (PEP) use, dog vaccination, and patient risk assessments with integrated bite case management (IBCM) were proposed to be cost-effective, evidence is still lacking in China. We aim to evaluate the future burdens of dog-mediated human rabies deaths in the next decade and provide quantitative evidence on the cost-effectiveness of different rabies-control strategies in China. METHODS: Based on data from China's national human rabies surveillance system, we used decision-analytic modelling to estimate dog-mediated human rabies death trends in China till 2035. We simulated and compared the expected consequences and costs of different combination strategies of the status quo, improved access to PEP, mass dog vaccination, and use of IBCM. RESULTS: The predicted human rabies deaths in 2030 in China will be 308 (95%UI: 214-411) and remain stable in the next decade under the status quo. The strategy of improved PEP access alone could only decrease deaths to 212 (95%UI: 147-284) in 2028, remaining unchanged till 2035. In contrast, scaling up dog vaccination to coverage of 70% could eliminate rabies deaths by 2033 and prevent approximately 3,265 (95%UI: 2,477-3,687) extra deaths compared to the status quo during 2024-2035. Moreover, with the addition of IBCM, the "One Health" approach through mass dog vaccination could avoid unnecessary PEP use and substantially reduce total cost from 12.53 (95%UI: 11.71-13.34) to 8.73 (95%UI: 8.09-9.85) billion US dollars. Even if increasing the total costs of IBCM from 100 thousand to 652.10 million US dollars during 2024-2035, the combined strategy of mass dog vaccination and use of IBCM will still dominate, suggesting the robustness of our results. CONCLUSIONS: The combined strategy of mass dog vaccination and IBCM requires collaboration between health and livestock/veterinary sectors, and it could eliminate Chinese rabies deaths as early as 2033, with more deaths averted and less cost, indicating that adding IBCM could reduce unnecessary use of PEP and make the "One Health" rabies-control strategy most cost-effective.
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Mordeduras e Picadas , Raiva , Humanos , Cães , Animais , Raiva/epidemiologia , Raiva/prevenção & controle , Raiva/veterinária , Objetivos , Vacinação , Profilaxia Pós-Exposição/métodosRESUMO
The FlyRNAi database at the Drosophila RNAi Screening Center and Transgenic RNAi Project (DRSC/TRiP) provides a suite of online resources that facilitate functional genomics studies with a special emphasis on Drosophila melanogaster. Currently, the database provides: gene-centric resources that facilitate ortholog mapping and mining of information about orthologs in common genetic model species; reagent-centric resources that help researchers identify RNAi and CRISPR sgRNA reagents or designs; and data-centric resources that facilitate visualization and mining of transcriptomics data, protein modification data, protein interactions, and more. Here, we discuss updated and new features that help biological and biomedical researchers efficiently identify, visualize, analyze, and integrate information and data for Drosophila and other species. Together, these resources facilitate multiple steps in functional genomics workflows, from building gene and reagent lists to management, analysis, and integration of data.
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Biologia Computacional/métodos , Bases de Dados Genéticas , Drosophila melanogaster/genética , Genoma de Inseto/genética , Genômica/métodos , Interferência de RNA , Animais , Animais Geneticamente Modificados , Proteínas de Drosophila/genética , Perfilação da Expressão Gênica/métodos , Armazenamento e Recuperação da Informação , InternetRESUMO
Studies of the adult Drosophila midgut have led to many insights in our understanding of cell-type diversity, stem cell regeneration, tissue homeostasis, and cell fate decision. Advances in single-cell RNA sequencing provide opportunities to identify new cell types and molecular features. We used single-cell RNA sequencing to characterize the transcriptome of midgut epithelial cells and identified 22 distinct clusters representing intestinal stem cells, enteroblasts, enteroendocrine cells (EEs), and enterocytes. This unbiased approach recovered most of the known intestinal stem cells/enteroblast and EE markers, highlighting the high quality of the dataset, and led to insights on intestinal stem cell biology, cell type-specific organelle features, the roles of new transcription factors in progenitors and regional variation along the gut, 5 additional EE gut hormones, EE hormonal expression diversity, and paracrine function of EEs. To facilitate mining of this rich dataset, we provide a web-based resource for visualization of gene expression in single cells. Altogether, our study provides a comprehensive resource for addressing functions of genes in the midgut epithelium.
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Sistema Digestório/metabolismo , Drosophila/metabolismo , Células-Tronco/metabolismo , Transcriptoma , Animais , Sistema Digestório/citologia , Drosophila/citologia , Drosophila/genética , Proteínas de Drosophila/metabolismo , Enterócitos/metabolismo , Células Enteroendócrinas/metabolismo , Células Epiteliais/metabolismo , Epitélio/metabolismo , Regulação da Expressão Gênica , Hormônios/metabolismo , Intestinos/citologia , Células-Tronco/citologia , Fatores de Transcrição/metabolismoRESUMO
A fuzzy PI controller was utilized to realize the modal matching between a driving and detecting model. A simulation model was built to study electrostatic decoupling controlling technology. The simulation results show that the modal matching can be gained by the fuzzy PI controller. The frequency difference between the driving mode and the detection mode is less than 1 Hz, and the offset of the input DC is smaller than 0.6 V. The optimal proportionality factor and integral coefficient are 1.5 and 20, respectively. The fuzzy PI controlling technology provides a good way for the parameter optimization to gain modal matching of micro gyro, via which the detecting accuracy and stability can be improved greatly.
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Graphene oxide (GO) has shown remarkable performance in the multiple-equilibrium-route adsorption (MER) process, which is characterized by further activation of GO through an in-situ reduction process based on single-equilibrium-route adsorption (SER), generating new adsorption sites and achieving an adsorption capacity increase. However, the effect of GO on MER adsorption in lateral size and thickness is still unclear. Here, GO sheets were sonicated for different lengths of time, and the adsorption of MER and SER was investigated at three temperatures to remove the typical cationic dye, acridine orange (AO). After sonication, we found that freshly prepared GO was greatly reduced in lateral size and thickness. In about 30 min, the thickness of GO decreased dramatically from several atomic layers to fewer atomic layers to a single atomic layer, which was completely stripped off; after that, the monolayer lateral size reduction dominated until it remained constant. Surface functional sites, such as hydroxyl groups, showed little change in the experiments. However, GO mainly reduces the C=O and C-O bonds in MER, except for the conjugated carbon backbone (C-C). The SER adsorption kinetics of all temperatures fitted the pseudo-first-order and pseudo-second-order models, yet room temperature preferred the latter. An overall adsorption enhancement appeared as sonication time, but the equilibrium capacity of SER GO generally increased with thickness and decreased with the single-layer lateral size, while MER GO conversed concerning the thickness. The escalated temperature facilitated the exfoliation of GO regarding the adsorption mechanism. Thus, the isotherm behaviors of the SER GO changed from the Freundlich model to Langmuir as size and temperature changed, while the MER GO were all of the Freundlich. A record capacity of ~4.3 g of AO per gram of GO was obtained from the MER adsorption with a sixty-minute ultrasonicated GO at 313.15 K. This work promises a cornerstone for MER adsorption with GO as an adsorbent.
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The pathophysiological effects of a number of metabolic and age-related disorders can be prevented to some extent by exercise and increased physical activity. However, the molecular mechanisms that contribute to the beneficial effects of muscle activity remain poorly explored. Availability of a fast, inexpensive, and genetically tractable model system for muscle activity and exercise will allow the rapid identification and characterization of molecular mechanisms that mediate the beneficial effects of exercise. Here, we report the development and characterization of an optogenetically-inducible muscle contraction (OMC) model in Drosophila larvae that we used to study acute exercise-like physiological responses. To characterize muscle-specific transcriptional responses to acute exercise, we performed bulk mRNA-sequencing, revealing striking similarities between acute exercise-induced genes in flies and those previously identified in humans. Our larval muscle contraction model opens a path for rapid identification and characterization of exercise-induced factors.
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Músculo Esquelético , Condicionamento Físico Animal , Animais , Drosophila/genética , Humanos , Larva/genética , Contração Muscular/fisiologia , Músculo Esquelético/metabolismoRESUMO
BACKGROUND AND AIMS: Noise exposure is a major public health challenge with important implications for cardiovascular health. However, the association between noise exposure and stroke risk remains controversial. Therefore, we aimed to evaluate the role of noise exposure on stroke incidence and mortality by conducting a dose-response meta-analysis of cohort studies. METHODS: The relevant publications were retrieved via PubMed, Embase, Web of Science, and Scopus up to June 26, 2022. The potential linear and curve relationship between noise and stroke were fitted using the generalized least squares method and restricted cubic spline. We estimated the pooled relative risk (RR) with 95% confidence interval (CI) by random-effect models. The Grading of Recommendations Assessment Development and Evaluation (GRADE) approach was used to evaluate the strength of the results. RESULTS: In total, 21 cohort studies with 16,075,204 participants and 311,878 cases were included in the analysis. The risk of stroke incidence increased up to 4% (95% CI:1.02-1.06) and stroke mortality increased up to 3% (95% CI:1.00-1.07), every 10 dB(A) increment in noise exposure. Moreover, each 10 dB(A) increment in noise exposure was associated with a 4% (95% CI:1.01-1.07) increase in ischemic stroke and a 2% (95% CI:1.00-1.04) increase in hemorrhagic stroke. According to GRADE criteria, the evidence level in this study was rated as moderate. CONCLUSIONS: The current findings provide further evidence of a dose-response relationship between exposure to noise and the risk of stroke incidence and mortality. Additionally, we update and fill a knowledge gap that the statistically significant increase in stroke incidence when noise decibels are >65 dB(A).
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Acidente Vascular Cerebral , Estudos de Coortes , Humanos , Incidência , Mortalidade , Ruído , Ruído Ocupacional , Acidente Vascular Cerebral/epidemiologiaRESUMO
With the increasingly serious air pollution and the rampant coronavirus disease 2019 (COVID-19), preparing high-performance air filter to achieve the effective personal protection has become a research hotspot. Electrospun nanofibrous membrane has become the first choice of air filter because of its small diameter, high specific surface area and porosity. However, improving the filtration performance of the filter only cannot meet the personal needs: it should be given more functions based on high filtration performance to maximize the personal benefits, called, multifunctional, which can also be easily realized by electrospinning technology, and has attracted much attention. In this review, the filtration mechanism of high-performance electrospun air filter is innovatively summarized from the perspective of membrane. On this basis, the specific preparation process, advantages and disadvantages are analyzed in detail. Furthermore, other functions required for achieving maximum personal protection benefits are introduced specifically, and the existing high-performance electrospun air filter with multiple functions are summarized. Finally, the challenges, limitations, and development trends of manufacturing high-performance air filter with multiple functions for personal protection are presented.
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Merkel cell carcinoma (MCC) is a rare but aggressive neuroendocrine carcinoma of the skin, often associated with polyomavirus and ultra-violet light exposure. Immunosuppression is associated with increased risk of development of MCC, including that associated with hematolymphoid disorders such as chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL). We sought to determine whether MCC arising in patients with hematologic disorders showed unique features. Searching archived material at three institutions, we identified 13 patients with MCC and at least one hematologic malignancy and 41 patients with MCC with no reported hematologic malignancy. CLL/SLL was the most common hematologic disorder in this setting (9/13 cases). Clinical history, variation in morphologic appearance, unusual site distribution and concern for progression of underlying hematologic disease all contributed to potential diagnostic challenges. Overlapping marker expression between MCC and hematologic neoplasms created potential diagnostic pitfalls (e.g. CD138, Pax5, TdT, Bcl2, CD56, and CD117). In addition, we newly identify expression of CD5 and LEF-1 in a subset of MCC, including in patients with CLL/SLL. MCC in patients with hematologic malignancy were more common in men (92% versus 59%, p < 0.05) and showed an unusual site predilection to non-sun exposed sites (3/13 on the buttocks) with none presenting on the face or scalp. By contrast, face or scalp lesions were common in MCC without an associated hematologic malignancy (17/41, p < 0.05). Our findings reaffirm the need for skin surveillance in the setting of immune deficiency and for vigilance to identify unusual presentations of MCC in patients with or without hematologic disorders.
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Carcinoma de Célula de Merkel/patologia , Doenças Hematológicas/patologia , Neoplasias Cutâneas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Célula de Merkel/complicações , Feminino , Doenças Hematológicas/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Cutâneas/complicaçõesRESUMO
OBJECTIVE: The bonding interface of dental filling therapy is the weak point in resisting secondary caries. Adhesives containing nanoparticles of amorphous calcium phosphate (NACP) and dimethylaminohexadecyl methacrylate (DMAHDM) have been demonstrated in vitro to prevent bacteria from producing acid and to promote tooth remineralization. The present study aimed to evaluate the efficacy of adhesive with NACP and DMAHDM to prevent secondary caries in vivo. MATERIALS AND METHODS: Artificial cavities were created on the first molar on both sides of the maxillary in a rat model. One side was treated with adhesive containing NACP + DMAHDM, while on the other side, a commercial adhesive served as control. After 24 days of cariogenic feeding, the degree of secondary caries was evaluated by micro-CT and a modified Keyes scoring method. Quantitative real-time PCR (qPCR) and colony-forming unit (CFU) counts were used to evaluate the antibacterial efficacy of the materials. Biocompatibility was also investigated. RESULTS: In the rat model, the adhesive with NACP + DMAHDM showed excellent biocompatibility and effectively decreased the amount of bacteria. The experimental group demonstrated excellent remineralization effectiveness, with a lower modified Keyes score and mineral loss of 34.16 ± 2.13 vol% µm, compared with 77.44 ± 7.22 vol% µm in the control group, according to micro-CT (P < 0.05), showing excellent capacity to inhibit secondary caries. CONCLUSIONS: The NACP-DMAHDM-containing adhesive exhibited good performance in preventing secondary caries in vivo. CLINICAL RELEVANCE: Adhesives containing NACP and DMAHDM have great potential for use in clinical dentistry to prevent secondary caries by inhibiting bacterial growth and promoting remineralization.
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Biofilmes , Suscetibilidade à Cárie Dentária , Animais , Antibacterianos/farmacologia , Fosfatos de Cálcio/farmacologia , Cimentos Dentários/farmacologia , Metacrilatos/farmacologia , Metilaminas , Ratos , Remineralização Dentária/métodosRESUMO
Quercetin is a plant-derived polyphenol flavonoid that has been proven to be effective for many diseases. However, the mechanism and in vivo metabolism of quercetin remains to be clarified. It achieves a wide range of biological effects through various metabolites, gut microbiota and its metabolites, systemic mediators produced by inflammation and oxidation, as well as by multiple mechanisms. The all-round disease treatment of quercetin is achieved through the organic combination of multiple channels. Therefore, this article clarifies the metabolic process of quercetin in the body, and explores the new pattern of action of quercetin in the treatment of diseases.
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Microbioma Gastrointestinal , Quercetina , Flavonoides/farmacologia , Estrutura Molecular , Quercetina/farmacologiaRESUMO
OBJECTIVES: Dental caries is closely associated with acid-producing bacteria, and Streptococcus mutans is one of the primary etiological agents. Bacterial accumulation and dental demineralization lead to destruction of bonding interface, thus limiting the longevity of composite. The present study investigated remineralization effectiveness of adhesive containing nanoparticles of amorphous calcium phosphate (NACP) in a stimulated oral biofilm environment. METHODS: The enamel blocks were immersed in demineralization solution for 72 h to imitate artificial initial carious lesion and then subjected to a Streptococcus mutans biofilm for 24 h. All the samples then underwent 4-h demineralization in brain heart infusion broth with sucrose (BHIS) and 20-h remineralization in artificial saliva (AS) for 7 days. The daily pH of BHIS after 4-h incubation, lactic acid production, colony-forming unit (CFU) count, and content of calcium (Ca) and phosphate (P) in biofilm were evaluated. Meanwhile, the remineralization effectiveness of enamel was analyzed by X-ray diffraction (XRD), surface microhardness testing, transverse microradiography (TMR) and scanning electron microscopy (SEM). RESULTS: The NACP adhesive released abundant Ca and P, achieved acid neutralization, reduced lactic acid production, and lowered CFU count (P < 0.05). Enamel treated with NACP adhesive demonstrated the best remineralization effectiveness with remineralization value of 52.29 ± 4.79% according to TMR. Better microhardness recovery of cross sections and ample mineral deposits were also observed in NACP group. CONCLUSIONS: The NACP adhesive exhibited good performance in remineralizing initial enamel lesion with cariogenic biofilm. SIGNIFICANCE: The NACP adhesive is promising to be applied for the protection of bonding interface, prevention of secondary caries, and longevity prolonging of the restoration.
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Cárie Dentária , Nanopartículas , Antibacterianos , Biofilmes , Fosfatos de Cálcio , Cárie Dentária/tratamento farmacológico , Suscetibilidade à Cárie Dentária , Cimentos Dentários , Humanos , Metacrilatos , Remineralização DentáriaRESUMO
The carbon-emission transfer between two representative developing economies - China and Africa - behind the international trade has aroused quite a few controversies, which have not been fully estimated and understood yet. In this paper, the Multiregional Input-Output (MRIO) method is applied to the participants of Forum on China-Africa Cooperation (FOCAC) from the global perspective to reveal the roles both China and Africa have played in the global supply chain as either the original emitter or the final consumer, and to depict the evolution pattern of carbon transfer via Sino-Africa trade from the year 2000-2015. The findings are as follows: 1) China has played the role of net exporter of embodied carbon-emission in Sino-Africa trade, for the amount of emitted carbon China had born yet resulted by consumption in Africa well surpassed that vice versa. 2) Compared to the carbon-emission flows embodied in EU-Africa and US-Africa trades, China has shouldered more carbon-emission derived from Africa's consumption. 3) The sectoral contribution and intensities of embodied carbon-emission correspond to the trading pattern between China and Africa, which stems from the two parties' comparative advantages and economic complementarity. 4) The intensities of embodied carbon-emission on both sides are declining towards a rosy prospect, which indicates an improving carbon-emission efficiency of both economies. From a global perspective, both China and Africa play a positive part in carbon-emission reduction. The results in this study can facilitate low-carbon and high-efficiency trading link between the two economies.