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Pathogen detection is growing in importance in the early stages of bacterial infection and treatment due to the significant morbidity and mortality associated with bloodstream infections. Although various diagnostic approaches for pathogen detection have been proposed, most of them are time-consuming, with insufficient sensitivity and limited specificity and multiplexing capability for clinical use. Here, we report a force-encoding DNA nanomachine for simultaneous and high-throughput detection of multiple pathogens in blood through force-induced remnant magnetization spectroscopy (FIRMS). The force-encoding DNA nanomachines coupled with DNA walkers enable analytical sensitivity down to a single bacterium via a cascade signal amplification strategy. More importantly, it allows for rapid and specific profiling of various pathogens directly in blood samples, without being affected by factors such as light color and solution properties. We expect that this magnetic sensing platform holds great promise for various applications in biomedical research and clinical diagnostics.
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Infecções Bacterianas , Técnicas Biossensoriais , Sepse , Humanos , DNA , Bactérias/genéticaRESUMO
Non-radiative recombination losses limit the property of perovskite solar cells (PSCs). Here, a synergistic strategy of SnSe2QDs doping into SnO2 and chlorhexidine acetate (CA) coating on the surface of perovskite is proposed. The introduction of 2D SnSe2QDs reduces the oxygen vacancy defects and increases the carrier mobility of SnO2. The optimized SnO2 as a buried interface obviously improves the crystallization quality of perovskite. The CA containing abundant active sites of âNH2/âNHâ, âCâN, CO, âCl groups passivate the defects on the surface and grain boundary of perovskite. The alkyl chain of CA also improves the hydrophobicity of perovskite. Moreover, the synergism of SnSe2QDs and CA releases the residual stress and regulates the energy level arrangement at the top and bottom interface of perovskite. Benefiting from these advantages, the bulk and interface non-radiative recombination loss is greatly suppressed and thereby increases the carrier transport and extraction in devices. As a result, the best power conversion efficiency (PCE) of 23.41% for rigid PSCs and the best PCE of 21.84% for flexible PSCs are reached. The rigid PSC maintains 89% of initial efficiency after storing nitrogen for 3100 h. The flexible PSCs retain 87% of the initial PCE after 5000 bending cycles at a bending radius of 5 mm.
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In this paper, the aluminium-doped carbon dots (Al-CDs) were developed for simultaneous selective detection of five tetracycline antibiotics (TCs), including minocycline (MC), tetracycline (TC), oxytetracycline (OTC), doxycycline (DOC) and chlortetracycline (CTC). With the bright blue fluorescence, Al-CDs displayed excellent stability and showed no obvious fluorescence intensity changes under different ionic strength, acidic or alkaline environment, continuous ultraviolet light illumination, and even longtime storage at room temperature. As adding different antibiotics, the fluorescence of Al-CDs was strongly quenched by five TCs and showed no distinguished changes with the addition of other kinds of antibiotics. The presence of interferential metal ions, anions and small organic molecules imposed no effect on the simultaneous selective detection of five TCs. A good linear relationship was achieved for five TCs in the range of 0-100 µM, and the limit of detection for MC, TC, OTC, DOC, and CTC were 13.91 (0-100 µM), 15.54 (0-100 µM), 14.26 (0-100 µM), 13.48 (0-100 µM) and 13.88 nM (0-100 µM), respectively. Moreover, Al-CDs was successfully used to the detection of five TCs in real samples with recovery ranging from 92.47% to 122.05%, confirming a bright future for the practical applications in the assays of foods, medicines, and environments.
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OBJECTIVES: Despite receiving cardiopulmonary resuscitation (CPR) training, over 50% of bystanders were unable to actually perform CPR. Understanding public willingness and attitudes toward bystander CPR is crucial in explaining whether people initiate CPR. This study aimed to develop a theoretical understanding of factors that influence the public's willingness and attitudes to perform CPR. DESIGN: This was a qualitative study using the grounded theory method. METHODS: The data were collected from semi-structured interviews with 28 participants between August 2022 and November 2022. Purposive sampling and theoretical sampling were used to recruit participants. Interviews were recorded and transcribed. Data were analyzed using open, axial, and selective coding. RESULTS: Nine categories and 24 subcategories were summarized from four aspects: willingness, attitudes, implementation, and training. Willingness included self-willingness, self-perception, and societal factors; attitudes covered personality traits, reactions to patients and environment; implementation comprised knowledge and skills, situational coping, and risk perception; training included CPR training accessibility and barriers to CPR training. A theoretical framework of public CPR willingness, attitudes, and their influencing factors was developed. CONCLUSION: The public's CPR willingness, attitudes, training, and implementation were interrelated and influential. The findings may have significant implications for the development of legislation and policy related to CPR popularization and training.
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Reanimação Cardiopulmonar , Parada Cardíaca Extra-Hospitalar , Humanos , Reanimação Cardiopulmonar/educação , Reanimação Cardiopulmonar/métodos , Teoria Fundamentada , Conhecimentos, Atitudes e Prática em Saúde , Inquéritos e Questionários , Pesquisa Qualitativa , Parada Cardíaca Extra-Hospitalar/terapiaRESUMO
BACKGROUND: The cardiopulmonary resuscitation (CPR) compression to ventilation strategy remains controversial. We conducted a meta-analysis to compare the outcomes between continuous chest compressions CPR with asynchronous ventilation (CCC-CPR) and interrupted chest compressions CPR with synchronous ventilation (ICC-CPR) in cardiac arrest. METHODS: PubMed, Web of Science, Embase, MEDLINE (Ovid/LWW) and the Cochrane Libraries were searched up from inception to July 31, 2022. Human and animal studies comparing CCC-CPR versus ICC-CPR were included. Outcome variables were return of spontaneous circulation (ROSC), time to ROSC, survival to discharge, 1-month survival, survival at 4 h, good neurological function, mean arterial pressure (MAP) and other clinical parameters. Jadad Scale and Newcastle-Ottawa Scale were used to assess the study quality and risk of bias. RESULTS: The systematic search identified eight studies on humans and twelve studies on animal trials. There were no significant differences in ROSC (odd ratios [OR] 1.07; 95% confidence interval [CI]: 0.86-1.32; P = 0.55), survival to hospital discharge (OR 1.04; 95%CI 0.77-1.42; P = 0.79), 1-month survival (OR 1.07; 95%CI 0.84-1.36; P = 0.57), and good neurological outcome (OR 0.92; 95%CI 0.84-1.01, P = 0.09) between CCC-CPR and ICC-CPR in human studies. In animal trials, CCC-CPR had significantly higher rate of ROSC (OR = 1.81; 95% CI: 0.94-3.49; P = 0.07), survival at 4 h (OR 2.57; 95% CI: 1.16-5.72; P = 0.02) and MAP (mean difference [MD] 0.79, 95% CI: 0.04-1.53; P = 0.04), even though no significant differences in ROSC time, arterial potential of hydrogen (pH) and partial tension of carbon dioxide (PaCO2). CONCLUSION: CCC-CPR did not show superiority in human outcomes compared with ICC-CPR, but its effect value was significantly increased in animal experiments. We should take the positive outcomes from animals and apply them to human models, and more physiological mechanisms need to be confirmed in CPR patients with different compression-ventilation strategies to improve the prognosis of cardiac arrest.
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Reanimação Cardiopulmonar , Parada Cardíaca , Animais , Humanos , Parada Cardíaca/terapia , Prognóstico , Alta do Paciente , PressãoRESUMO
Multiplexed simultaneous detection of various cancer markers is required for accurate diagnosis and treatment of early cancer. In this work, we present a force-coded strategy for the simultaneous detection of tumor-related proteins with tunable dynamic range via magnetic sensing. The multiplexing capability of this method is achieved by designing DNA devices that can recognize different biomarkers and code them with different binding forces measured by the force-induced remnant magnetization spectroscopy, which is not influenced by the color of the light and the solution. Moreover, the force-coded assay with high sensitivity and adjustable detection range is robust, which could be used for practical biological applications such as magnetic sensing, handheld miniaturized systems, and potential in vivo diagnosis.
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Técnicas Biossensoriais , Neoplasias , Biomarcadores , Técnicas Biossensoriais/métodos , DNA/química , Humanos , Neoplasias/diagnóstico , ProteínasRESUMO
BACKGROUND: The optimal airway management strategy for cardiac arrest remains unclear. This study aimed to compare the effects of different initial airway interventions on improving clinical outcomes based on the 2010 cardiopulmonary resuscitation (CPR) guidelines and later. METHODS: We searched PubMed, EMBASE, and the Cochrane Library for CPR articles tailored to each database from October 19, 2010, to July 31, 2021, to compare endotracheal intubation (ETI), supraglottic airway (SGA), or bag-valve-mask ventilation (BMV). The initial results and long-term results were investigated by meta-analysis. RESULTS: Twenty-five articles (n = 196,486) were included. The ROSC rate in the ETI group (ES = 0.49, 95% CI: 0.38-0.59) was significantly higher than that in the SGA group (ES = 0.27, 95% CI: 0.20-0.34) and BMV group (ES = 0.24, 95% CI: 0.17-0.31). The rate of ROSC upon admission to the hospital in the ETI group (ES = 0.27, 95% CI: 0.13-0.42) was significantly higher than that in the SGA group (ES = 0.18, 95% CI: 0.13-0.23) and BMV group (ES = 0.16, 95% CI: 0.10-0.22). Compared with the BMV group (ES = 0.09, 95% CI: 0.04-0.14) and the SGA group (ES = 0.08, 95% CI: 0.05-0.10), the ETI group (ES = 0.14, 95% CI: 0.10-0.17) had a higher discharge rate, but all of the groups had the same neurological outcome (ETI group [ES = 0.06, 95% CI: 0.04-0.08], BMV group [ES = 0.05, 95% CI: 0.03-0.08] and SGA group [ES = 0.04, 95% CI: 0.03-0.05]). CONCLUSIONS: Opening the airway is significantly associated with improved clinical outcomes, and the findings suggest that effective ETI based on mask ventilation should be implemented as early as possible once the patient has experienced cardiac arrest.
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Reanimação Cardiopulmonar , Serviços Médicos de Emergência , Parada Cardíaca Extra-Hospitalar , Adulto , Manuseio das Vias Aéreas/métodos , Reanimação Cardiopulmonar/métodos , Serviços Médicos de Emergência/métodos , Humanos , Intubação Intratraqueal/métodos , Respiração ArtificialRESUMO
Biomolecules participate in various physiological and pathological processes through intermolecular interactions generally driven by non-covalent forces. In the present review, the force-induced remnant magnetization spectroscopy (FIRMS) is described and illustrated as a novel method to measure non-covalent forces. During the FIRMS measurement, the molecular magnetic probes are magnetized to produce an overall magnetization signal. The dissociation under the interference of external force yields a decrease in the magnetic signal, which is recorded and collected by atomic magnetometer in a spectrum to study the biological interactions. Furthermore, the recent FIRMS development with various external mechanical forces and magnetic probes is summarized.
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Magnetismo , Fenômenos Mecânicos , Microscopia de Força Atômica/métodos , Sondas Moleculares , Análise EspectralRESUMO
OBJECTIVES: Most Vietnamese immigrants in the U.S. today arrived as political refugees due to the Vietnam War in the late 20th century. Refugees are disproportionally affected by health and mental health disparities as a result of experiencing distress and potentially traumatic experiences before, during, and after their migration processes. This study involved Vietnamese families facing dementia and used a qualitative approach to investigate participants' experiences before, during, and right after their resettlement in the U.S. METHODS: In-person interviews were conducted with 11 Vietnamese adults who cared for their family member with dementia. A descriptive analysis approach was used. RESULTS: Five major themes emerged from the interviews:1) immigrating separately from family members, 2) difficult and unsafe journeys, 3) experiences of loss, 4) lack of support systems in the U.S., and 5) feelings of unhappiness, sadness, or signs of depression. CONCLUSIONS: This study provides a close examination of Vietnamese refugees' unique backgrounds and how individuals with dementia and their caregivers from this population may be disproportionally impacted by stress. CLINICAL IMPLICATIONS: To reduce health disparities, we recommend that providers and policymakers allocate more resources for culturally appropriate routine assessment, treatment, and referrals of those with dementia and their caregivers.
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Demência , Refugiados , Povo Asiático , Demência/terapia , Humanos , Pesquisa Qualitativa , Refugiados/psicologia , VietnãRESUMO
Vaccinium dunalianum Wight, usually processed as a traditional folk tea beverage, is widely distributed in the southwest of China. The present study aimed to investigate the antioxidant, α-glucosidase and pancreatic lipase inhibitory activities of V.dunalianum extract and isolate the bioactive components. In this study, the crude extract (CE) from the buds of V. dunalianum was prepared by the ultrasound-assisted extraction method in 70% methanol and then purified with macroporous resin D101 to obtain the purified extract (PM). Five fractions (Fr. A-E) were further obtained by MPLC column (RP-C18). Bioactivity assays revealed that Fr. B with 40% methanol and Fr. D with 80% methanol had better antioxidant with 0.48 ± 0.03 and 0.62 ± 0.01 nM Trolox equivalent (TE)/mg extract for DPPH, 0.87 ± 0.02 and 1.58 ± 0.02 nM TE/mg extract for FRAP, 14.42 ± 0.41 and 19.25 ± 0.23 nM TE/mg extract for ABTS, and enzyme inhibitory effects with IC50 values of 95.21 ± 2.21 and 74.55 ± 3.85 for α-glucosidase, and 142.53 ± 11.45 and 128.76 ± 13.85 µg/mL for pancreatic lipase. Multivariate analysis indicated that the TPC and TFC were positively related to the antioxidant activities. Further phytochemical purification led to the isolation of ten compounds (1-10). 6-O-Caffeoylarbutin (7) showed significant inhibitory effects on α-glucosidase and pancreatic lipase enzymes with values of 38.38 ± 1.84 and 97.56 ± 7.53 µg/mL, and had the highest antioxidant capacity compared to the other compounds.
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Antioxidantes/isolamento & purificação , Arbutina/análogos & derivados , Ácidos Cafeicos/isolamento & purificação , Flavonoides/isolamento & purificação , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Lipase/química , Vaccinium/química , alfa-Glucosidases/química , Antioxidantes/química , Arbutina/química , Arbutina/isolamento & purificação , Benzotiazóis/antagonistas & inibidores , Benzotiazóis/química , Compostos de Bifenilo/química , Ácidos Cafeicos/química , Flavonoides/química , Inibidores de Glicosídeo Hidrolases/química , Lipase/antagonistas & inibidores , Lipase/metabolismo , Extração Líquido-Líquido/métodos , Metanol/química , Picratos/química , Extratos Vegetais/química , Folhas de Planta/química , Solventes/química , Sonicação , Ácidos Sulfônicos/antagonistas & inibidores , Ácidos Sulfônicos/química , alfa-Glucosidases/metabolismoRESUMO
Caring for a family member with Alzheimer's disease (AD) or a related dementia is stressful, and this may especially be the case for racial/ethnic minority caregivers. This study examined the feasibility and acceptability of a pilot intervention for Vietnamese American dementia caregivers. A secondary, exploratory aim was to examine post-intervention effects on AD knowledge and psychosocial outcomes. Of the 87 individuals contacted, 32 met inclusion criteria. Of this number, 14 enrolled in the study with 11 caregivers completing the intervention, and 10 of the 11 completing 3-month follow-up data. Caregivers provided positive feedback on the intervention and had higher scores on AD knowledge and self-efficacy in seeking support services post-intervention, with the effect on self-efficacy maintained at 3-month follow-up. Recruitment for the intervention was difficult; however, once caregivers came to the first session, they were engaged and found the classes informative. Recommendations for a future intervention are discussed.
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Doença de Alzheimer/enfermagem , Asiático/educação , Cuidadores/educação , Idoso , Idoso de 80 Anos ou mais , Asiático/psicologia , Cuidadores/psicologia , Efeitos Psicossociais da Doença , Demência/enfermagem , Estudos de Viabilidade , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Projetos PilotoRESUMO
As a type of novel noncoding RNAs, circular RNAs (circRNAs) have attracted great interest due to its different characteristics from linear RNAs. They are abundantly and stably present in the transcriptome of eukaryotic cells, with development stage specificity and high conservatism. Because circRNAs are not easily degraded by exonuclease RNase R, they can exist more stably in body fluids than linear RNAs. Based on these unique conditions, circRNAs have great potential value as clinical diagnostic and prognostic markers. As the research deepens, more and more evidences suggest that circRNAs may be closely associated with many diseases, especially cancer. Numerous studies have demonstrated the abnormal expression of circRNAs in cancer, and they can regulate the occurrence and progression of cancer by targeting key genes. Abundant circRNAs in tissues and cells can be released into saliva and blood. It is undeniable that circRNAs are a class of promising future biomarkers for cancer diagnosis and prognosis. Here we summarize the researches on circRNAs and cancer over the past few years. We expect this summary to be a stepping stone to further exploration of possible circRNAs as cancer biomarkers.
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Biomarcadores Tumorais/análise , Neoplasias/diagnóstico , RNA Neoplásico/análise , RNA/análise , Bases de Dados Genéticas , Detecção Precoce de Câncer , Feminino , Previsões , Humanos , Masculino , Neoplasias/química , Neoplasias/genética , RNA/genética , RNA Circular , RNA Neoplásico/genéticaRESUMO
Circular RNA (circRNA) is an important class of noncoding RNA characterized by covalently closed continuous loop structures. In recent years, the various functions of circRNAs have been continuously documented, including effects on cell proliferation and apoptosis and nutrient metabolism. The liver is the largest solid organ in mammals, and it also performs many functions in the body, which is considered to be the busiest organ in the body. At the same time, the liver is vulnerable to multiple pathogenic factors, causing various acute and chronic liver diseases. The pathogenesis of liver disease is still not fully understood. As a rising star for the past few years, circRNAs have been proven involved in the regulation of liver homeostasis and disease. This chapter will explain the role of circRNAs in liver health and diseases and sort out the confusion in the present study.
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Hepatopatias/genética , Fígado/metabolismo , RNA/genética , Biomarcadores Tumorais , Detecção Precoce de Câncer , Regulação da Expressão Gênica/genética , Humanos , Cirrose Hepática/genética , Cirrose Hepática/metabolismo , Hepatopatias/metabolismo , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Regeneração Hepática/genética , RNA/metabolismo , RNA Circular , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismoRESUMO
Sarcopenia is a common clinical symptom in aging and patients with wasting diseases, characterized by a decreased skeletal muscle mass. As a consequence of lifestyle change, the nonalcoholic fatty liver disease (NAFLD) presents a rising trend. In the past three decades, increasing evidence has proved that sarcopenia is related to NAFLD. In this chapter, we will summarize the emerging evidence of the predictive role of sarcopenia in NAFLD and review the diagnosis value, feasible mechanism, and therapy strategies of sarcopenia in NAFLD. Sarcopenia is a potential risk factor for NAFLD, and targeting sarcopenia can benefit NAFLD to some extent.
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Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Sarcopenia/fisiopatologia , Humanos , Fatores de RiscoRESUMO
While many seizure detection methods have demonstrated great accuracy, their training necessitates a substantial volume of labeled data. To address this issue, we propose a novel method for unsupervised seizure anomaly detection called SAnoDDPM, which uses denoising diffusion probabilistic models (DDPM). We designed a novel pipeline that uses a variable lower bound on Markov chains to identify potential values that are unlikely to occur in anomalous data. The model is first trained on normal data, then anomalous data is input to the trained model. The model resamples the anomalous data and converts it to normal data. Finally, the presence of seizures can be determined by comparing the before and after data. Moreover, the input 2D spectrograms are encoded into vector-quantized representations, which enables powerful and efficient DDPM while maintaining its quality. Experimental comparisons on the publicly available datasets, CHB-MIT and TUH, show that our method delivers better results, significantly reduces inference time, and is suitable for deployment in a clinical environments. As far as we are aware, this is the first DDPM-based method for seizure anomaly detection. This novel approach significantly contributes to the progression of seizure detection algorithms, thereby augmenting their practicality in clinical settings.
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Eletroencefalografia , Cadeias de Markov , Modelos Estatísticos , Convulsões , Humanos , Convulsões/diagnóstico , Convulsões/fisiopatologia , Eletroencefalografia/métodos , Aprendizado de Máquina não Supervisionado , Algoritmos , Processamento de Sinais Assistido por ComputadorRESUMO
Single-atom nanozymes (SAzymes), with well-defined and uniform atomic structures, are an emerging type of natural enzyme mimics. Currently, it is important but challenging to rationally design high-performance SAzymes and deeply reveal the interaction mechanism between SAzymes and substrate molecules. Herein, this work reports the controllable fabrication of a unique Cu-N1S2-centred SAzyme (Cu-N/S-C) via a chemical vapor deposition-based sulfur-engineering strategy. Benefiting from the optimized geometric and electronic structures of single-atom sites, Cu-N/S-C SAzyme shows boosted enzyme-like activity, especially in catalase-like activity, with a 13.8-fold increase in the affinity to hydrogen peroxide (H2O2) substrate and a 65.2-fold increase in the catalytic efficiency when compared to Cu-N-C SAzyme with Cu-N3 sites. Further theoretical studies reveal that the increased electron density around single-atom Cu is achieved through electron redistribution, and the efficient charge transfer between Cu-N/S-C and H2O2 is demonstrated to be more beneficial for the adsorption and activation of H2O2. The as-designed Cu-N/S-C SAzyme possesses an excellent antitumor effect through the synergy of catalytic therapy and oxygen-dependent phototherapy. This study provides a strategy for the rational design of SAzymes, and the proposed electron redistribution and charge transfer mechanism will help to understand the coordination environment effect of single-atom metal sites on H2O2-mediated enzyme-like catalytic processes.
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Peróxido de Hidrogênio , Neoplasias , Humanos , Engenharia , Engenharia Química , Fototerapia , Catálise , Gases , Neoplasias/terapiaRESUMO
The dysregulation of sex hormone levels is associated with metabolic disorders such as obesity. Inonotus obliquus polysaccharide (IOP) exhibits a promising therapeutic effect on conditions like obesity and diabetes, potentially linked to its influence on intestinal microbiota and metabolism. The exact cause and mechanisms that link sex hormones, gut microbiota and metabolism are still unknown. In this research, we examined the molecular weight, monosaccharide composition, and glycosidic bond type of IOP. We found that IOP mostly consists of alpha-structured 6carbon glucopyranose, with a predominant (1 â 4) linkage to monosaccharides and a uniform distribution. Following this, we administered two different concentrations of IOP to mice through gavage. The results of the enzyme-linked immunosorbent assay (ELISA) demonstrated a significant increase in testosterone (T) levels in the IOP group as compared to the control group. Additionally, the results of tissue immunofluorescence indicated that increased IOP led to a decrease in adiponectin content and an increase in SET protein expression. The study also revealed changes in the intestinal microbiota and metabolic changes in mice through 16S rRNA data and non-targeted LC-MS data, respectively. The study also found that IOP mainly affects pathways linked to glycerophospholipid metabolism. In addition, it has been observed that there is an increase in the number of beneficial bacteria, such as the Eubacterium coprostanoligenes group and g.Lachnospiraceae NK4A136 group, while the levels of metabolites that are linked to obesity or diabetes, such as 1,5-anhydrosorbitol, are reduced. Furthermore, biomarker screening has revealed that the main microorganism responsible for the differences between the three groups is g.Erysipelatoclostridiaceae. In summary, these findings suggest that IOP exerts its therapeutic effects through a synergistic interplay between sex hormones, gut microbiome composition, and metabolic processes.
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Diabetes Mellitus , Microbioma Gastrointestinal , Inonotus , Camundongos , Masculino , Animais , RNA Ribossômico 16S/genética , Polissacarídeos/farmacologia , Hormônios Esteroides Gonadais , ObesidadeRESUMO
The prevention of chronic wound formation has already been a primary subject in wound management, particularly for deep wounds. The electrospun nanofiber membranes hold tremendous potential in the prevention of chronic wounds due to their micro/nano pore structures. Currently, many natural and synthetic materials have been utilized in the fabrication of nanofiber membranes. However, striking a balance between the structural stability and the biocompatibility remains challenging. It is necessary not only to ensure the long-term durability of nanofiber membranes but also to enhance their biocompatibility for alleviating patients' suffering. In this study, we reported a nanofiber membrane dressing with excellent biocompatibility and mechanical properties, which is potential for the treatment of deep wounds. The basal material chosen for the preparation of the nanofiber membrane was a co-polyester (NI-LPGD5) synthesized by non-isocyanate polyurethane (NIPU) and polyglycolic acid with a dihydroxy structure (LPGD-synthesized from glycolic acid and neopentyl glycol). Moreover, curcumin was also added as a bioactive substance to enhance the pro-healing effect of dressings. The physicochemical properties of the prepared nanofiber membranes were characterized through various physicochemical tools. Our results demonstrated that the NI-LPGD5 co-polymer can be electrospun into smooth fibers. Meanwhile, curcumin-loaded nanofiber membranes (Cur/NI-LPGD5) also exhibited a favorable microscopic morphology. The fabricated membranes exhibited suitable mechanical properties, outstanding hygroscopic-swelling rate and water vapor transmittance. Besides, in vitro cell culturing, the cells on the NI-LPGD5 membrane maintained their maximum viability. The potential of in vivo wound healing was further demonstrated through animal experiments. The experimental results showed that the nanofiber membranes effectively prevented chronic wounds from forming and promoted granulation tissue growth without replacing the dressing throughout the healing process. We also found that these nanofiber membranes could effectively promote the expression of related biomarkers to accelerate wound healing, particularly the Cur/NI-LPGD5 membrane. In conclusion, the fabricated membranes possess suitable physicochemical properties and promising bioactivity. As a result, it effectively prevented the formation of chronic wounds and demonstrated significant potential in reducing the frequency of dressing changes.
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Introduction: and objectives: Extracellular vesicles (EVs) have emerged as key players in intercellular communication within the context of non-alcoholic fatty liver disease (NAFLD). This study aims to explore the intricate crosstalk between hepatocytes and hepatic stellate cells (HSCs) mediated by EVs in NAFLD. Materials and methods: EVs ferritin was detected in hepatocytes stimulated with free fatty acids (FFA) as well as in NAFLD mice. Deferoxamine (DFO) was employed to reduce ferritin levels, while GW4869 was utilized to inhibit EVs. The impact of EVs ferritin on the HSCs activation was evaluated both in vitro and in vivo. Additionally, serum EVs ferritin levels were compared between NAFLD patients and controls. Results: FFA treatment induces the formation and secretion of EVs and facilitates the release of ferritin from hepatocytes via EVs. Subsequently, EVs ferritin is hijacked by HSCs, prompting accelerated HSCs activation. Silencing ferritin with DFO and inhibiting EVs formation and secretion with GW4869 can reverse the effects of FFA treatment and disrupt the communication between hepatocytes and HSCs. Accumulation of ferritin leads to excessive reactive oxygen species (ROS) production, promoting HSCs fibrogenesis. Conversely, depleting EVs ferritin cargo restores liver function, concurrently mitigating NAFLD-associated fibrosis. Notably, NAFLD patients exhibit significantly elevated levels of serum EVs ferritin. Conclusions: This study unveils a previously underestimated role of ferritin in HSCs upon its release from hepatocytes, emphasizing DFO as a promising compound to impede NAFLD advancement.