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Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) have garnered extensive attention as natural product-based nanomedicines and potential drug delivery vehicles. However, the specific mechanism for regulating MSC-EVs secretion and delivery remains unclear. Here, we demonstrate that extracellular matrix (ECM) stiffness regulates the secretion and delivery of EVs by affecting MSCs' cargo sorting mechanically. Using multi-omics analysis, we found that a decrease in ECM stiffness impeded the sorting of vesicular transport-related proteins and autophagy-related lipids into MSC-EVs, impairing their secretion and subsequent uptake by macrophages. Hence, MSC-EVs with different secretion and uptake behaviors can be produced by changing the stiffness of culture substrates. This study provides new insights into MSC-EV biology and establishes a connection between MSC-EV behaviors and ECM from a biophysical perspective, providing a basis for the rational design of biomedical materials.
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Vesículas Extracelulares , Células-Tronco Mesenquimais , Vesículas Extracelulares/metabolismo , Comunicação Celular , Transporte Biológico , Transdução de SinaisRESUMO
OBJECTIVES: Cerebral venous sinus thrombosis (CVST) can cause sinus obstruction and stenosis, with potentially fatal consequences. High-resolution magnetic resonance imaging (HRMRI) can diagnose CVST qualitatively, although quantitative screening methods are lacking for patients refractory to anticoagulation therapy and who may benefit from endovascular treatment (EVT). Thus, in this study, we used radiomic features (RFs) extracted from HRMRI to build machine learning models to predict response to drug therapy and determine the appropriateness of EVT. MATERIALS AND METHODS: RFs were extracted from three-dimensional T1-weighted motion-sensitized driven equilibrium (MSDE), T2-weighted MSDE, T1-contrast, and T1-contrast MSDE sequences to build radiomic signatures and support vector machine (SVM) models for predicting the efficacy of standard drug therapy and the necessity of EVT. RESULTS: We retrospectively included 53 patients with CVST in a prospective cohort study, among whom 14 underwent EVT after standard drug therapy failed. Thirteen RFs were selected to construct the RF signature and CVST-SVM models. In the validation dataset, the sensitivity, specificity, and area under the curve performance for the RF signature model were 0.833, 0.937, and 0.977, respectively. The radiomic score was correlated with days from symptom onset, history of dyslipidemia, smoking, fibrin degradation product, and D-dimer levels. The sensitivity, specificity, and area under the curve for the CVST-SVM model in the validation set were 0.917, 0.969, and 0.992, respectively. CONCLUSIONS: The CVST-SVM model trained with RFs extracted from HRMRI outperformed the RF signature model and could aid physicians in predicting patient responses to drug treatment and identifying those who may require EVT.
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Metal nanostructures of chiral geometry interacting with light via surface plasmon resonances can produce tailorable optical activity with their structural alterations. However, bottom-up fabrication of arbitrary chiral metal nanostructures with precise size and morphology remains a synthetic challenge. Here we develop a DNA origami-enabled aqueous solution metallization strategy to prescribe the chirality of silver nanostructures in three dimensions. We find that diamine silver(I) complexes coordinate with the bases of prescribed single-stranded protruding clustered DNA (pcDNA) on DNA origami via synergetic interactions including coordination, hydrogen bonds, and ion-π interaction, which induce site-specific pcDNA condensation and local enrichment of silver precursors that lowers the activation energy for nucleation. Using tubular DNA origami-based metallization, we obtain helical silver patterns up to a micrometer in length with well-defined chirality and pitches. We further demonstrate tailorable plasmonic optical activity of metallized chiral silver nanostructures. This method opens new pathways to synthesize programmable inorganic materials with arbitrary morphology and chirality.
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DNA/química , Nanopartículas Metálicas/química , Prata/química , Ligação de Hidrogênio , Tamanho da PartículaRESUMO
DNA, a biological macromolecule, is a naturally evolved information material. From the structural point of view, an individual DNA strand can be considered as a chain of data with its bases working as single units. For decades, due to the high biochemical stability, large information storage capacity, and high recognition specificity, DNA has been recognized as an attractive material for information processing. Especially, the chemical synthesis strategies and DNA sequencing techniques have been rapidly developed recently, further enabling encoding information with synthetic DNA molecules. Herein, recent progresses are summarized on information processing based on synthetic DNA molecules from three aspects including information storage, computation, and encryption, and proposed the challenges and future development directions.
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DNA , Nanotecnologia , Sequência de BasesRESUMO
OBJECTIVE: To understand the status of health literacy and its influencing factors among the residents in Haidian District of Beijing, and to provide references for targeted health education intervention. METHODS: A multi-staged probability proportionate to size sampling(PPS) sampling method was used to collect 7034 residents that aged 15-69 years old in Haidian District in 2018. RESULTS: The standardized rate of health literacy among the residents of Haidian District was 28. 56%. The standardized health literacy rate of basic health knowledge and concept literacy, health lifestyle and behavior literacy, basic health skill were 35. 79%, 30. 90% and 36. 39%, respectively. The standardized health literacy rate of 6 health literacy issues from high to low were safety and first aid(66. 39%), scientific health perspectives(51. 24%), infectious diseases prevention and treatment(39. 78%), health information(30. 25%), chronic disease control and prevention(13. 33%), and basic medical care(11. 23%), respectively. The result of multiple logistic regression showed that aged between 30-39 years old, female, high school education and above, the teacher, medical and government staff, staff of other institutions, staff of other enterprises, other employees and the annual income of the family>45000 RMB were protective factors for health literacy. Aged between 50-69 years old was risk factor for health literacy. CONCLUSION: The level of health literacy in Haidian District was low. Various forms of intervention activities should be carried out to improve the residents' health literacy, especially focused on health lifestyle and behavior literacy, chronic disease control and prevention and basic medical care.
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Letramento em Saúde , Adulto , Idoso , Pequim , Cidades , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Pessoa de Meia-Idade , Inquéritos e QuestionáriosRESUMO
Females typically outlive males in animals, especially in species that provide long-term maternal care. However, life history theory predicts that investments in reproduction, such as lactation and offspring nursing, often shorten caretakers' longevity. Aiming to interpret this paradox, we selected the lactating jumping spider Toxeus magnus to investigate the effects of reproductive activities on longevity for two sexes. We found that: (1) although "milk" provisioning reduces female's longevity, mothers who cared for offspring (provisioned "milk" and nursing) lived the longest compared to virgins and those did not provide care; (2) copulation increased female's longevity but had no effects on males; and (3) the two sexes have comparable developmental duration, but the female adult's longevity was 2.1 times that of male's. This study suggests that the time requirement for offspring dispersal might act as a key selective force favoring females' adulthood extension, which ultimately generates the longer-lived females in maternal cared species.
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Bisphenol A (BPA) is a widely used plasticizer known to cause various disorders. Despite a global reduction in the use of BPA-containing products, prenatal exposure to low-dose BPA, even those below established safety limits, has been linked to neurological and behavioral deficits in childhood. The precise mechanisms underlying these effects remain unclear. In the present study, we observed a significant increase in the number of cortical neurons in offspring born to dams exposed to low-dose BPA during pregnancy. We also found that this prenatal exposure to low-dose BPA led to increased proliferation but reduced migration of cortical neurons. Transcriptomic analysis via RNA sequencing revealed an aberrant activation of the cAMP-PKA-CREB pathway in offspring exposed to BPA. The use of H89, a selective PKA inhibitor, effectively rescued the deficits in both proliferation and migration of cortical neurons. Furthermore, offspring from dams exposed to low-dose BPA exhibited manic-like behaviors, including hyperactivity, anti-depressant-like responses, and reduced anxiety. While H89 normalized hyperactivity, it didn't affect the other behavioral changes. These results suggest that the overactivation of PKA plays a causative role in BPA-induced changes in neuronal development. Our data also indicate that manic-like behaviors induced by prenatal low-dose BPA exposure may be influenced by both altered neuronal development and abnormal PKA signaling in adulthood.
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Ubiquitous humic substances usually exhibit strong interfering effects on target pollutant removal in advanced water purification. This work aims to develop a photochemical conversion system on the nonstoichiometric TiO2 for pollutant removal in environmentally relevant matrices. In this synergistic reaction system, the redox-reactive humic substances and defective oxygen vacancies can serve as the organic electron transfer mediator and the key surface reactive sites, respectively. This system achieves a superior pollutant degradation in real surface water at low oxidant concentrations. Reactive oxygen vacancies on the TiO2 surface and sub-surface are of considerable interest for this photochemical reaction system. By engineering defective oxygen vacancies on high-energy {001} polar facet, the surface and electronic interactions between tailored TiO2 and humic substances are greatly strengthened for the promoted electron transfer and oxidant activation. Rendered by the strong surface affinity and molecular activation, defective oxygen vacancies thermodynamically and dynamically promote reactive chain reactions for free radical formation, including the selective O2 reduction to ·O2- and the H2O2 activation to ·OH. Our findings take new insights into environmental geochemistry, and provide an effective strategy to in-situ boost the humic substances-mediated water purification without secondary pollution. ENVIRONMENTAL IMPLICATION: Humic substances are widely distributed in aquatic environment, thus playing important roles in environmental geochemistry. For example, humic substances can achieve good surface adsorption through electrostatic adsorption, ligand exchange and electronic interactions with typical TiO2 to form reactive ligand-metal charge transfer complexes for pollutant degradation. Inspired by the unique properties of surface and sub-surface oxygen vacancies, the defective TiO2 was designed to refine the humic substances-mediated photochemical reactions. A superior reactivity was measured for pollutant degradation. Our findings provide an effective strategy to boost naturally photochemical decontamination in environmentally relevant matrices.
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Transition metals are promising catalysts for environmental remediation. However, their low reactivity, poor stability and weak reusability largely limit practical applications. Herein, we report that the electron-rich dissolved black carbon (DBC) incorporated into the nanoscale zero-valent copper (nZVCu) can boost intrinsic reactivity, structural stability and cyclic reusability for superior peroxymonosulfate (PMS) activation and pollutant degradation. A series of refractory pollutants can be effectively removed on the DBC/nZVCu, in comparison with the nZVCu reference. Hydroxyl radical (â§OH) is identified as the dominant reactive oxygen species by electron spin resonance (ESR) and chemical quenching tests, mediated by the metastable Cu(III) as the key reactive intermediate. The electron-rich DBC protects nanoscale Cu from oxidative corrosion to slow down the surface formation of inert CuO layer, rendered by the thermodynamically and dynamically capacitive regulation of corrosive electron transfer from metallic core. By this refining way, the conducive DBC improves the neighboring utilization of reactive electron during metal corrosion, oxidant activation, radical generation and pollutant degradation in Fenton-like catalysis. Our findings suggest that the ubiquitous DBC can be an efficient chelating agent to refine transition metals by serving as the surface deactivator and electron mediator, and take new insights into their environmental and agricultural geochemistry.
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OBJECTIVE: To discuss the relevant predicative factors of dural arteriovenous fistula (dAVF) in intracranial hemorrhage. METHODS: A total of 144 consecutive patients with dAVFs were recruited for a retrospective analysis from 1996 to 2006. The relevant factors of gender, age, fistula flow rate, arterial supply, lesion and venous drainage pattern were analyzed to evaluate the outcome of intracranial hemorrhage. RESULTS: Univariate analysis showed that gender, lesion and venous drainage pattern were statistical significant for intracranial hemorrhage of DAVF (P < 0.05). However, only venous drainage pattern was significant in the predication of intracranial hemorrhage (P < 0.05). CONCLUSION: Only venous drainage pattern is significant in the predication of dural arteriovenous fistulas in intracranial hemorrhage. Both gender and lesion may be confounding factors.
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Malformações Vasculares do Sistema Nervoso Central/complicações , Hemorragias Intracranianas/etiologia , Adolescente , Adulto , Idoso , Drenagem/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Adulto JovemRESUMO
This study proposes the Sulphate reduction, mixed sulphide- and thiosulphate-driven Autotrophic denitrification, Nitrification, and Anammox integrated (SANIA) process for sustainable treatment of mainstream wastewater after organics capture. Three moving-bed biofilm reactors (MBBRs) were applied for developing sulphate reduction (SR), mixed sulphide- and thiosulphate-driven partial denitrification and Anammox (MSPDA), and NItrification (N), respectively. Typical mainstream wastewater after organics capture (e.g., chemically enhanced primary treatment, CEPT) was synthesized with chemical oxygen demand (COD) of 110 mg/L, sulphate of 50 mg S/L, ammonium of 30 mgN/L. The feasibility of SANIA was investigated with mimic nitrifying effluent supplied in MSPDA-MBBR (Period I), followed by the examination of the applicability of SANIA process with N-MBBR integrated (Period II), under moderate temperatures (25-27 â). In Period I, SANIA process was established with both SR- and MSPDA-MBBR continuously operated for over 300 days (no Anammox biomass inoculation). Specifically, in MSPDA-MBBR, high rates of denitratation (2.7 gN/(m2·d)) and Anammox (2.8 gN/(m2·d)) were achieved with Anammox contributing to 81 % of the total inorganic nitrogen removal. In Period II, the integrated SANIA system was continuously operated for over 130 days, achieving up to 90 % of COD, 93 % of ammonium, and 61 % of total inorganic nitrogen (TIN) removal, with effluent concentrations lower than 10 mg COD/L, 3 mg NH4+-N/L, and 13 mg TIN-N/L. The implementation of SANIA can ultimately reduce 75 % and 40 % of organics and aeration energy for biological nitrogen removal. Considering the combination of SANIA with CEPT for carbon capture and sludge digestion/incineration for energy recovery, the new integrated wastewater technology can be a promising strategy for sustainable wastewater treatment.
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Compostos de Amônio , Purificação da Água , Nitrificação , Águas Residuárias , Desnitrificação , Tiossulfatos , Biofilmes , Oxidação Anaeróbia da Amônia , Reatores Biológicos , Oxirredução , Esgotos , NitrogênioRESUMO
A novel tri-layer membrane consisting of polycaprolactone (PCL) fibrous sheets and structured nanofibers with a gelatin (Gt) shell and a simvastatin-containing PCL core (PCL-Gt/PCL-simvastatin membrane) was prepared. The soft external layer comprised of Gt/PCL-simvastatin, the external layer of PCL and the middle layer of both microfilaments, interwoven together. The membrane was designed to promote osteoinduction and act as a barrier against cells but not against water and molecules in order to promote guided bone regeneration. The structure of the membrane was characterized by scanning electronic microscopy. The in vitro release rates of simvastatin over 32 days were determined by high-performance liquid chromatography. For in vitro biological assays, bone marrow mesenchymal stem cells and human fibroblasts were cultured on the different surfaces of the membrane. Cell adhesion, proliferation, distribution, and differentiation were examined. For in vivo testing, cranial defects were created in rabbits to assess the amount of new bone formed for each membrane. The results revealed that membranes with multi-layered structures showed good cell viability and effective osteoinductive and barrier properties. These results suggest that the novel multi-layered PCL-Gt/PCL-simvastatin membranes have great potential for bone tissue engineering.
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Antimony tin oxide (ATO)/lead selenide (PbSe) composite was rationally designed and fabricated on fluorine doped tin oxide glass (FTO) for using as counter electrode (CE) of quantum dot sensitized solar cells (QDSSCs). The electrocatalytic activity of the CE is deeply investigated in the polysulfide electrolyte by employing the Tafel, electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) of the symmetrical cells. The results confirm that the ATO/PbSe CE has better electrocatalytic activity and stability than that of PbSe CE obtained by pulse voltage electrodeposition (PVD). The enhanced electrocatalytic performance of ATO/PbSe CE can be attributed to its high specific surface area, excellent permeability, conductivity and interface connectivity, which provide more electrocatalytic active sites for the reduction of polysulfide species, as well as fast channels for ions diffusion and electron transport. As a result, the CdS QDSSCs and CdS/CdSe co-sensitized QDSSCs assembled by the ATO/PbSe CE exhibits better power conversion efficiency (η) of 1.72% and 5.59%, respectively than that of PbSe CE obtained by PVD. Furthermore, photovoltaic property of the ATO/PbSe CE in CdS/CdSe co-sensitized QDSSCs keeps stable for over 200 min. This present work provides a simple and effective strategy for the construction of high-performance CE materials of QDSSCs.
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Antibiotic resistance is becoming one of the major crises, among which hydrolysis reaction is widely employed by bacteria to destroy the reactive pharmacophore. Correspondingly, antibiotic producer has canonically co-evolved this approach with the biosynthetic capability for self-resistance. Here we discover a self-defense strategy featuring with reductive inactivation of hemiaminal pharmacophore by short-chain dehydrogenases/reductases (SDRs) NapW and homW, which are integrated with the naphthyridinomycin biosynthetic pathway. We determine the crystal structure of NapW·NADPH complex and propose a catalytic mechanism by molecular dynamics simulation analysis. Additionally, a similar detoxification strategy is identified in the biosynthesis of saframycin A, another member of tetrahydroisoquinoline (THIQ) antibiotics. Remarkably, similar SDRs are widely spread in bacteria and able to inactive other THIQ members including the clinical anticancer drug, ET-743. These findings not only fill in the missing intracellular events of temporal-spatial shielding mode for cryptic self-resistance during THIQs biosynthesis, but also exhibit a sophisticated damage-control in secondary metabolism and general immunity toward this family of antibiotics.
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Bactérias/metabolismo , Proteínas de Bactérias/metabolismo , Vias Biossintéticas , Simulação de Dinâmica Molecular , Tetra-Hidroisoquinolinas/metabolismo , Antibacterianos/biossíntese , Antibacterianos/química , Bactérias/genética , Proteínas de Bactérias/genética , Biocatálise , Cromatografia Líquida de Alta Pressão , Resistência Microbiana a Medicamentos/genética , Humanos , Isoquinolinas/química , Isoquinolinas/metabolismo , Espectrometria de Massas/métodos , Estrutura Molecular , NADP/química , NADP/metabolismo , Naftiridinas/química , Naftiridinas/metabolismo , Oxirredução , Oxirredutases/genética , Oxirredutases/metabolismo , Tetra-Hidroisoquinolinas/químicaRESUMO
Human chorionic gonadotropin (hCG) is a membrane-associated protein highly expressed in several types of human cancer cells. The expression in the cancer cells indicates that hCG may be a potential target molecule for cancer immunotherapy. The objective of this study was to develop a novel immunogenic molecule, which can efficiently induce the neutralizing antibody against hCG and which is also suitable for mass production. The immunogenicity of the recombinant single chain chimeric protein of hCGß-oLHα expressed by yeast was examined. Additionally, the inhibitory effects of the anti-hCGß-oLHα antibody on the growth of hCG-positive cancer cells were determined. It was found that hCGß-oLHα yielded high titers of anti-hCG rabbit antibody that could effectively neutralize the bioactivity of hCG. The rabbit anti-hCGß-oLHα IgG inhibited the proliferation of hCG-expressing human colorectal cancer cells (LS-174, HCT-116, HCT-15 and KM-12) in a dose-dependent manner. Furthermore, an intact anti-tumor vaccine was prepared by conjugating hCGß-oLHα with tetanus toxoid (TT) and this was used to immunize Balb/c mice bearing hCG-expressing SP2/0 tumor cells. The progression of tumors in these immunized mice was remarkably inhibited. These results suggest that hCGß-oLHα is a new promising immunogenic molecule for the development of an anti-hCG-based cancer vaccine.
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Vacinas Anticâncer/imunologia , Gonadotropina Coriônica Humana Subunidade beta/imunologia , Subunidade alfa de Hormônios Glicoproteicos/imunologia , Neoplasias Experimentais/terapia , Proteínas Recombinantes de Fusão/imunologia , Animais , Linhagem Celular Tumoral , Gonadotropina Coriônica Humana Subunidade beta/análise , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias Experimentais/patologia , Coelhos , Toxoide Tetânico/administração & dosagem , VacinaçãoRESUMO
OBJECTIVE: To explore the prevalence of gastroesophageal reflux disease (GERD) and its symptoms in Haidian district of Beijing, identify its associated risk factors and analyze the relations between GERD and history of other diseases. METHODS: 2615 residents of 18-80 years old were selected to participate in the study by multi-stage sampling from Haidian district from June and September in 2008. Questionnaires were distributed to obtain the information on demographic characteristics, diseases history and the reflux disease questionnaire (RDQ). RESULTS: The prevalence of GERD in the population was 8.4% (220/2615), and the prevalence of heartburn, reflux, both heartburn and reflux were 1.0% (25/2615), 6.2% (163/2615) and 1.2% (32/2615), respectively. Multi-factor analysis showed rural area (OR = 2.237, 95%CI: 1.422 - 3.517), female (OR = 1.456, 95%CI: 1.085 - 1.955), high education (OR = 1.242, 95%CI: 1.001 - 1.542), pressure (OR = 1.277, 95%CI: 1.089 - 1.497), bad emotional status (OR = 1.320, 95%CI: 1.046 - 1.665), and family history of gastrointestinal disorders (OR = 1.594, 95%CI: 1.075 - 2.365) were significantly associated with GERD. Rural area (OR = 2.481, 95%CI: 1.278 - 4.818), female (OR = 1.747, 95%CI: 0.902 - 3.386), drinking (OR = 1.838, 95%CI: 0.916 - 3.690), no exercise (OR = 2.091; 95%CI: 1.131 - 3.867) and bad emotional status (OR = 1.657, 95%CI: 1.123 - 2.446) were significant risk factors for heartburn. Rural area (OR = 2.171, 95%CI: 1.326 - 3.556), female (OR = 1.505, 95%CI: 1.102 - 2.056), high education (OR = 1.347, 95%CI: 1.063 - 1.706), pressure (OR = 1.317, 95%CI: 1.113 - 1.558), bad emotional status (OR = 1.266, 95%CI: 0.992 - 1.616), and family history of gastrointestinal disorders (OR = 1.739, 95%CI: 1.163 - 2.600) were significantly associated with reflux symptom. History of diseases such as inflammatory bowel disease, anxiety, depression, peptic ulcer, gastritis, and renal diseases were found to be significantly related to GERD and its symptoms. CONCLUSION: This area has epidemic of GERD, which was related to mental problems and unhealthy life style, and should be paid more attention by conducting effective community-based interventions.
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Refluxo Gastroesofágico/epidemiologia , Adulto , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Inquéritos e QuestionáriosRESUMO
OBJECTIVE: To Evaluate four kits for screening HIV antibody by comparing and analyzing the HIV antibody screening positive results and Western Blot (WB) test results. METHODS: From January 2004 to June 2009, three ELISA kits (Zhongshan, Biomérieux and Livzon) were used for initial screening HIV antibody. The reactive positive samples were reexamed by initial ELISA kit and a rapid kit (Abbot Determine HIV-1/2). All repeatedly reactive positive screening results were followed by WB test. RESULTS: A total of 193 (0.094%) WB confirmed positive results were obtained from 206 151 specimens. The sensitivities and predictive values of negative test result (PVN) of three ELISA kits were all 100% and those of Abbot Determine HIV-1/2 were 93.93%, and 91.67% respectively. All false negative results from Abbot were WB indeterminate. The specificities of Zhongshan, Biomérieux, Livzon and Abbot were 99.88%, 99.89%, 99.96% and 89.38%; the study predictive values of a positive test result (PVP) were 35.58%, 46.46%, 76.61% and 92.20%; the efficiencies were 99.88%, 99.89%, 99.96% and 91.98%; the areas under ROC curve of the three ELISA kits were 0.93, 0.99, and 0.95 respectively. PVP of Livzon was obviously higher than those of Zhongshan (chi(2) = 45.804, P = 0.000), Biomérieux (chi(2) = 25.231, P = 0.000) and Biomérieux was higher than Zhongshan (chi(2) = 2.488, P = 0.115). PVP of Abbot was highest (chi(2) = 18.633, P = 0.000, vs Livzon). There were some specimens with S/CO (optical density of sample/cut off) ratio < 6 or > or = 6 in all three groups with positive, indeterminate and negative WB results. The S/CO ratio from Zhongshan in confirmed positive group (14.29 + or - 2.63) was higher than in positive-negative group (2.80 + or - 3.25) (t = 17.652, P = 0.000). The S/CO ratio from Biomérieux in confirmed positive group(16.09 + or - 2.35) was higher than in positive-negative group (2.14 + or - 1.91) (t = 31.622, P = 0.000). The S/CO ratio from Livzon in confirmed positive group (11.54 + or - 1.95) was higher than in positive-indeterminate group (5.54 + or - 3.57) (t = 6.386, P = 0.000), positive-negative group (3.25 + or - 2.41) (t = 21.772, P = 0.000) and positive-indeterminate group was higher than positive-negative group (t = 2.301, P = 0.033). CONCLUSION: The performances of four HIV antibody screening kits are good but estimating WB confirming result in line with S/CO ratio is not available. All repeated screening positive results should be followed by confirmatory tests.
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Ensaio de Imunoadsorção Enzimática/métodos , Anticorpos Anti-HIV/sangue , Soropositividade para HIV/diagnóstico , Programas de Rastreamento , Kit de Reagentes para Diagnóstico , Sorodiagnóstico da AIDS/métodos , Western Blotting/métodos , Ensaio de Imunoadsorção Enzimática/estatística & dados numéricos , Humanos , Indicadores e Reagentes , Sensibilidade e EspecificidadeRESUMO
Misperception of nutritional status is common and hinders the progress of childhood obesity prevention. This study aimed to examine the effectiveness of a smartphone-assisted intervention to improve student and parental perception of students' nutritional status (underweight, normal weight, overweight, obese). We conducted a parallel-group controlled trial with a non-randomized design in three junior middle schools of Beijing, China in 2019. One school was allocated to the intervention group and two schools to the control group. A total of 573 students (aged 13.1 ± 0.4 years) participated in the trial. The 3-month intervention included three components: health education sessions for students and parents, regular monitoring of students' weight, and the provision of feedback via a smartphone application. Schools in the control group continued their usual practice. Primary outcomes included the student and parental accurate perception of students' nutritional status. The percentage of students' accurate perception of their own nutritional status in the intervention group increased from 49.0% to 59.2% from baseline to three months, whereas it decreased from 64.1% to 58.1% in the control group; the adjusted odds ratio (OR) between the two groups was 1.71 (95% confidence interval (CI): 1.13, 2.59). The intervention did not significantly improve parental perception of students' nutritional status (p > 0.05). The study findings provided a brief approach for improving perception of nutritional status among middle school students.
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Estado Nutricional , Serviços de Saúde Escolar , Smartphone , Adolescente , Pequim , Criança , China , Feminino , Humanos , Masculino , Instituições Acadêmicas , EstudantesRESUMO
Natural products containing benzoheterocyclic skeletons are widely found in plants and exhibit various pharmacological activities. To address the current limited availability of these compounds, we herein demonstrate the production of benzopyran, furanocoumarins, and pyranocoumarins in Streptomyces xiamenensis by employing prenyltransferases and two substrate-promiscuous enzymes, XimD and XimE. To avoid the degradation in S. xiamenensis, furanocoumarins and pyranocoumarins were also successfully produced in Escherichia coli. The production of linear furanocoumarins (marmesin) and angular pyranocoumarins (decursinol) reached 3.6 and 3.7 mg/L in shake flasks, respectively. To the best of our knowledge, this is the first report of the microbial production of the plant metabolites furanocoumarins and pyranocoumarins. Our study complements the missing link in the biosynthesis of pyranocoumarins by leveraging the catalytic promiscuity of microbial enzymes.
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Compostos Heterocíclicos/química , Streptomyces/metabolismo , Benzopiranos/química , Benzopiranos/metabolismo , Biocatálise , Produtos Biológicos/química , Produtos Biológicos/metabolismo , Dimetilaliltranstransferase/genética , Dimetilaliltranstransferase/metabolismo , Escherichia coli/química , Escherichia coli/metabolismo , Furocumarinas/biossíntese , Furocumarinas/química , Engenharia Genética , Compostos Heterocíclicos/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Piranocumarinas/química , Piranocumarinas/metabolismo , Streptomyces/química , Streptomyces/genética , Especificidade por SubstratoRESUMO
High adsorption capacity, good biocompatibility and low cost are highly demanded for biofilter used in ammonium-rich wastewater treatment. In this study, we used SEM, BET, XRD and 16S rRNA to document the evidence for good performance in adsorption and biodegradation in aged refuse. Parallel experiment between raw and inert refuse showed ammonium adsorption occurred at the initial week, with the highest ammonium removal efficiency of 90.36%, but saturated during the subsequent long-term operation. Meanwhile, over 6months' operation of an aged refuse biofilter was conducted to confirm that nitrification was the main pathway of ammonium conversion. The maximum nitrogen loading rate could reach up to as high as 1.28kg/m3/d, with ammonium removal efficiency at 99%. Further, high nitrifier biodiversity were detected with 'Nitrosomonas' and 'Nitrospira' in domination in the refuse. However, Nitrospira would outcompete Nitrosomonas under the oxygen limiting condition and resulted in the failure of partial nitrification. The physicochemical and biological analysis show that biodegradation is the main ammonium conversion pathway, which is the critical finding of this work. This investigation would help to accelerate the application of the aged refuse process in ammonium-rich wastewater treatment.