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Single particle collision is an important tool for size analysis at the individual particle level; however, due to complex dynamic behaviors of nanoparticles on the surface of an electrode, the accuracy of size discrimination is limited. A silver (Ag) nanoparticle (NP) was chosen as the research target, and the dynamic behavior of Ag NPs was simplified by enhancing adsorption between Ag NP and Au ultramicroelectrode (UME) in alkaline media. Immediately after, accurate dynamic and thermodynamic information on single Ag NP was accurately extracted from collision events, including current intensity, transferred charge, and duration time. On the basis that there were differences between parameters of different-sized Ag NPs, multiparameter size discrimination was proposed, which improved the accuracy compared to single-parameter discrimination. More intriguingly, multiparameter analysis was combined with artificial intelligence, a tool adept at processing multidimensional data, for the first time. Finally, artificial intelligence-assisted multiparameter size discrimination was successfully used to intelligently distinguish mixed Ag NPs, with an optimal accuracy of more than 95%. To sum up, the artificial intelligence-assisted multiparameter method showed an excellent ability to quickly achieve the most accurate size discrimination of nanoparticles at the level of individual particle and provide an effective guidance for the application of nanoparticles.
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A new chemodosimeter SWJT-31 with an aggregation-induced emission (AIE) effect was designed and constructed. Upon increasing the water fraction in the solution, it exhibited typical AIE, which showed bright red fluorescence at 610 nm. SWJT-31 could sensitively and specifically recognize hydrazine by the TICT effect with an LOD of 33.8 nM, which was much lower than the standard of the USEPA. A portable test strip prepared using SWJT-31 was also developed for the visual detection of hydrazine. Eventually, it was successfully used for the detection of hydrazine in water samples and HeLa cells.
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Corantes Fluorescentes , Hidrazinas , Imidazóis , Hidrazinas/química , Humanos , Células HeLa , Imidazóis/química , Imidazóis/síntese química , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Imagem Óptica , Estrutura MolecularRESUMO
Ergot alkaloids (EAs) are a diverse group of indole alkaloids known for their complex structures, significant pharmacological effects, and toxicity to plants. The biosynthesis of these compounds begins with chanoclavine-I aldehyde (CC aldehyde, 2), an important intermediate produced by the enzyme EasDaf or its counterpart FgaDH from chanoclavine-I (CC, 1). However, how CC aldehyde 2 is converted to chanoclavine-I acid (CC acid, 3), first isolated from Ipomoea violacea several decades ago, is still unclear. In this study, we provide in vitro biochemical evidence showing that EasDaf not only converts CC 1 to CC aldehyde 2 but also directly transforms CC 1 into CC acid 3 through two sequential oxidations. Molecular docking and site-directed mutagenesis experiments confirmed the crucial role of two amino acids, Y166 and S153, within the active site, which suggests that Y166 acts as a general base for hydride transfer, while S153 facilitates proton transfer, thereby increasing the acidity of the reaction. KEY POINTS: ⢠EAs possess complicated skeletons and are widely used in several clinical diseases ⢠EasDaf belongs to the short-chain dehydrogenases/reductases (SDRs) and converted CC or CC aldehyde to CC acid ⢠The catalytic mechanism of EasDaf for dehydrogenation was analyzed by molecular docking and site mutations.
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Aldeídos , Alcaloides de Claviceps , Aldeídos/metabolismo , Aldeídos/química , Domínio Catalítico , Alcaloides de Claviceps/biossíntese , Alcaloides de Claviceps/química , Alcaloides de Claviceps/metabolismo , Simulação de Acoplamento Molecular , Mutagênese Sítio-Dirigida , Oxirredução , Oxirredutases/metabolismo , Oxirredutases/genética , Oxirredutases/químicaRESUMO
In situ monitoring of the agglomeration/aggregation process of nanoparticles (NPs) is crucial because it seriously affects cell entry, biosafety, catalytic performance of NPs, and so on. Nevertheless, it remains hard to monitor the solution phase agglomeration/aggregation of NPs via conventional techniques such as electron microscopy, which requires sample pretreatment and cannot represent native state NPs in solution. Considering that single-nanoparticle electrochemical collision (SNEC) is powerful to detect NPs in solution at the single-particle level, and the current lifetime, which refers to the time that current intensity decays to 1/e of the original value, is skilled in distinguishing different sized NPs, herein, a current lifetime-based SNEC has been developed to distinguish a single Au NP (d = 18 nm) from its agglomeration/aggregation. Based on this, the agglomeration/aggregation process of small-sized NPs and the discrimination of agglomeration vs aggregation have been carefully investigated at the single-particle level. Results showed that the agglomeration/aggregation of Au NPs (d = 18 nm) in 0.8 mM HClO4 climbed from 19% to 69% over two hours, whereas there was no visible granular sediment, and Au NPs tended to agglomerate rather than aggregate irreversibly under normal conditions. Hence, the proposed current lifetime-based SNEC could serve as a complementary method to in situ monitor the agglomeration/aggregation of small-sized NPs in solution at the single-particle level and provide effective guidance for the practical application of NPs.
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Background: To establish a modified Global Registry of Acute Coronary Events (GRACE) scoring system with an improved predictive performance compared with the traditional GRACE scoring system. Methods: We identified 5512 patients who were hospitalized with a definite diagnosis of acute myocardial infarction (AMI) from January 1, 2015, to December 31, 2020, at the Heart Center of the First Affiliated Hospital of Xinjiang Medical University through the hospital's electronic medical record system. A total of 4561 patients were enrolled after the inclusion and exclusion criteria were applied. The mean follow-up was 51.8 ± 23.4 months. The patients were divided into dead and alive groups by endpoint events. The differences between the two groups were compared using the two-sample t test and chi-square test. Adjusted traditional risk factors as well as LogBNP (B-type natriuretic peptide precursor, BNP) and the modified GRACE scoring system were included in a multifactorial COX regression model. The predictive performance of the traditional and modified GRACE scoring systems was compared by (Receiver Operating Characteristic) ROC curves. Results: Significant differences in age, heart rate, creatinine, uric acid, LogBNP, traditional GRACE score, and modified GRACE score were found between the dead and alive groups by the two-sample t test. Comparison of the two groups by the chi-square test revealed that the dead group had a higher incidence of males; higher cardiac function class; a previous history of hypertension, diabetes, coronary artery disease (CAD), or cerebrovascular disease; a history of smoking; the need for intra-aortic balloon pump (IABP) support; and more patients taking aspirin, clopidogrel, ticagrelor, and ß -blockers. The results were analyzed by a multifactorial COX regression model, and after adjusting for confounders, age, cardiac function class, history of CAD, use of aspirin and ß -blockers, and the modified GRACE scoring system were found to be associated with all-cause mortality (ACM) in patients with AMI. The ROC curve was used to compare the predictive performance of the conventional GRACE scoring system with that of the modified GRACE scoring system, and it was found that the modified GRACE scoring system (Area Under Curve (AUC) = 0.809, p < 0.001, 95% (Confidence Interval) CI (0.789-0.829)) was significantly better than the traditional GRACE scoring system (AUC = 0.786, p < 0.001, 95% CI (0.764-0.808)), the comparison between the two scores was statistically significant (p < 0.001). The change in the C statistic after 10-fold crossover internal validation of the modified GRACE score was not significant, and the integrated discrimination improvement (IDI) between the old and new models was calculated with IDI = 0.019 > 0, suggesting that the modified GRACE score has a positive improvement on the traditional GRACE score. Conclusions: The modified GRACE scoring system, established by combining B-type natriuretic peptide precursor (BNP) and the traditional GRACE scoring system, was independently associated with ACM in patients with AMI, with a larger AUC and higher predictive value than the traditional GRACE scoring system. Clinical Trial Registration: NCT02737956.
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Background: The ratio of fibrinogen to γ -glutamine transferase (FGR) was used to predict long-term prognosis in patients with coronary heart disease (CHD). Methods: A total of 5638 patients with CHD who were hospitalized from January 2008 to December 2016 were retrospectively enrolled in the study. The mean follow-up time was 35.9 ± 22.5 months. The follow-up endpoints were major cardiac and cerebrovascular adverse events (MACCE). The optimal FGR cut-off value was determined and divided into high- and low-FGR groups according to the receiver operating characteristic (ROC) curve. Statistical methods were used to compare the differences between the two groups and their prognoses to determine whether FGR can predict prognosis in patients with CHD. The traditional predictors were incorporated into the logistic regression model to observe the correlation between these indicators and all-cause mortality (ACM) events. We compared the prediction performance of FGR and traditional predictors on the occurrence of ACM events by ROC curves. Results: The optimal cut-off value was determined via a ROC analysis (FGR = 1.22, p = 0.002), and subjects were classified into high and low FGR groups. The follow-up found that the incidence of MACCE in the high FGR group was higher than that in the low FGR group. The COX multivariate regression model showed that high FGR was independently correlated with the occurrence of MACCE. In addition, the Kaplan-Meier survival curve showed that the risk of events was significantly increased in the group with high FGR. With increases in the FGR ratio, the risk of MACCE was increased. The ROC curve revealed that the risk of ACM was statistically different between the FGR and the traditional risk factor model (p = 0.002), (Fibrinogen (p = 0.008), γ -glutamine transferase (GGT) (p = 0.004), and N-terminal pro brain natriuretic peptide (NT-ProBNP) (p = 0.024)). The comparison between other different models were not statistically significant (p > 0.05). The area under the FGR model curve was larger than that of the traditional risk factors, fibrinogen, GGT and NT-ProBNP models. Conclusions: High FGR can increase the risk of MACCE in patients with CHD; additionally, it can be used as a new biomarker for long-term prognosis in CHD patients. Clinical Trial Registration: All details of this study are registered on the website (http://www.chictr.org.cn), registration number: ChiCTR-ORC-16010153.
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The onset of regular, strong, and progressive uterine contractions may result in both mechanical (compression of the fetal head and/or umbilical cord) and hypoxic (repetitive and sustained compression of the umbilical cord or reduction in uteroplacental oxygenation) stresses to a human fetus. Most fetuses are able to mount effective compensatory responses to avoid hypoxic-ischemic encephalopathy and perinatal death secondary to the onset of anaerobic metabolism within the myocardium, culminating in myocardial lactic acidosis. In addition, the presence of fetal hemoglobin, which has a higher affinity for oxygen even at low partial pressures of oxygen than the adult hemoglobin, especially increased amounts of fetal hemoglobin (ie, 180-220 g/L in fetuses vs 110-140 g/L in adults), helps the fetus to withstand hypoxic stresses during labor. Different national and international guidelines are currently being used for intrapartum fetal heart rate interpretation. These traditional classification systems for fetal heart rate interpretation during labor are based on grouping certain features of fetal heart rate (ie, baseline fetal heart rate, baseline variability, accelerations, and decelerations) into different categories (eg, category I, II, and III tracings, "normal, suspicious, and pathologic" or "normal, intermediary, and abnormal"). These guidelines differ from each other because of the features included within different categories and because of their arbitrary time limits stipulated for each feature to warrant an obstetrical intervention. This approach fails to individualize care because the "ranges of normality" for stipulated parameters apply to the population of human fetuses and not to the individual fetus in question. Moreover, different fetuses have different reserves and compensatory responses and different intrauterine environments (presence of meconium staining of amniotic fluid, intrauterine inflammation, and the nature of uterine activity). Pathophysiological interpretation of fetal heart rate tracing is based on the application of the knowledge of fetal responses to intrapartum mechanical and/or hypoxic stress in clinical practice. Both experimental animal studies and observational human studies suggest that, just like adults undertaking a treadmill exercise, human fetuses show predictable compensatory responses to a progressively evolving intrapartum hypoxic stress. These responses include the onset of decelerations to reduce myocardial workload and preserve aerobic metabolism, loss of accelerations to abolish nonessential somatic body movements, and catecholamine-mediated increases in the baseline fetal heart rate and effective redistribution and centralization to protect the fetal central organs (ie, the heart, brain, and adrenal glands), which are essential for intrauterine survival. Moreover, it is essential to incorporate the clinical context (progress of labor, fetal size and reserves, presence of meconium staining of amniotic fluid and intrauterine inflammation, and fetal anemia) and understand the features suggestive of fetal compromise in nonhypoxic pathways (eg, chorioamnionitis and fetomaternal hemorrhage). It is important to appreciate that the timely recognition of the speed of onset of intrapartum hypoxia (ie, acute, subacute, and gradually evolving) and preexisting uteroplacental insufficiency (ie, chronic hypoxia) on fetal heart rate tracing is crucial to improve perinatal outcomes.
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Cardiotocografia , Doenças do Recém-Nascido , Adulto , Animais , Feminino , Humanos , Gravidez , Hemoglobina Fetal , Frequência Cardíaca Fetal/fisiologia , Hipóxia , Inflamação , OxigênioRESUMO
Any acute and profound reduction in fetal oxygenation increases the risk of anaerobic metabolism in the fetal myocardium and, hence, the risk of lactic acidosis. On the contrary, in a gradually evolving hypoxic stress, there is sufficient time to mount a catecholamine-mediated increase in the fetal heart rate to increase the cardiac output and redistribute oxygenated blood to maintain an aerobic metabolism in the fetal central organs. When the hypoxic stress is sudden, profound, and sustained, it is not possible to continue to maintain central organ perfusion by peripheral vasoconstriction and centralization. In case of acute deprivation of oxygen, the immediate chemoreflex response via the vagus nerve helps reduce fetal myocardial workload by a sudden drop of the baseline fetal heart rate. If this drop in the fetal heart rate continues for >2 minutes (American College of Obstetricians and Gynecologists' guideline) or 3 minutes (National Institute for Health and Care Excellence or physiological guideline), it is termed a prolonged deceleration, which occurs because of myocardial hypoxia, after the initial chemoreflex. The revised International Federation of Gynecology and Obstetrics guideline (2015) considers the prolonged deceleration to be a "pathologic" feature after 5 minutes. Acute intrapartum accidents (placental abruption, umbilical cord prolapse, and uterine rupture) should be excluded immediately, and if they are present, an urgent birth should be accomplished. If a reversible cause is found (maternal hypotension, uterine hypertonus or hyperstimulation, and sustained umbilical cord compression), immediate conservative measures (also called intrauterine fetal resuscitation) should be undertaken to reverse the underlying cause. In reversible causes of acute hypoxia, if the fetal heart rate variability is normal before the onset of deceleration, and normal within the first 3 minutes of the prolonged deceleration, then there is an increased likelihood of recovery of the fetal heart rate to its antecedent baseline within 9 minutes with the reversal of the underlying cause of acute and profound reduction in fetal oxygenation. The continuation of the prolonged deceleration for >10 minutes is termed "terminal bradycardia," and this increases the risk of hypoxic-ischemic injury to the deep gray matter of the brain (the thalami and the basal ganglia), predisposing to dyskinetic cerebral palsy. Therefore, any acute fetal hypoxia, which manifests as a prolonged deceleration on the fetal heart rate tracing, should be considered an intrapartum emergency requiring an immediate intervention to optimize perinatal outcome. In uterine hypertonus or hyperstimulation, if the prolonged deceleration persists despite stopping the uterotonic agent, then acute tocolysis is recommended to rapidly restore fetal oxygenation. Regular clinical audit of the management of acute hypoxia, including the "the onset of bradycardia to delivery interval," may help identify organizational and system issues, which may contribute to poor perinatal outcomes.
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Bradicardia , Frequência Cardíaca Fetal , Gravidez , Feminino , Humanos , Bradicardia/terapia , Frequência Cardíaca Fetal/fisiologia , Desaceleração , Placenta , Hipóxia Fetal/terapiaRESUMO
OBJECTIVE: To clarify the effects of percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) on the clinical outcomes of patients with coronary heart disease (CHD) complicated with reduced ejection fraction heart failure (HFrEF) through meta-analysis. METHODS: Three major literature databases - PubMed, Web of Science, and Cochrane - were searched by search terms and the literature retrieval time was publications dating from January 2007 to December 2021. To search for observational studies and randomized controlled trials (RCT) comparing the efficacy of PCI and CABG in patients with CHD and HFrEF, the abstract or full text of the literature was read and the final included literature was determined, according to inclusion and exclusion criteria. The quality of the included literature was evaluated using the Ottawa scale and data extraction was further completed. Data analysis was made using RevMan5.4 and R4.1 software; relevant forest plots and funnel plots were made, according to the extracted data. Egger's test was used to evaluate whether the data had publication bias. Outcomes were the major adverse cardiovascular events (MACE). RESULTS: A total of 10 studies were included and 11,032 subjects were included, made up of 5,521 cases of PCI and 5,511 cases of CABG. The results showed no significant difference between the two groups in cardiac mortality (CM) (RR=1.13, 95% CI 0.98-1.30, P = 0.10) and in overall all-cause mortality (ACM) (RR=1.12, 95% CI 0.92-1.37, P = 0.25). In the subgroup analysis of ACM, in the subgroups with left ventricular ejection fraction (LVEF) less than 35% and exceeding 35% and less than 50% (RR=1.12, 95% CI 0.92-1.37, P = 0.25) between the two groups, there was no statistical difference. However, among other MACE, compared with the PCI group, the CABG group had a lower risk of MACE (RR=1.58, 95%CI 1.49-1.70, P < 0.00001), myocardial infarction (MI) (RR=1.99, 95% CI 1.02-3.88, P = 0.04), heart failure (HF) (RR=1.29, 95% CI 1.17-1.43, P < 0.00001) and revascularization (RR=2.74, 95% CI 1.93-3.90, P < 0.00001). Finally in the CABG group, the risk of stroke or transient ischemic attack (TIA) was higher (RR=0.71, 95% CI 0.58-0.86, P = 0.0006) than the PCI group. CONCLUSIONS: The mortality rates of PCI and CABG were similar in patients with CHD complicated with HFrEF. Compared with PCI, CABG had a lower incidence of MACE, MI, HF, and revascularization, and a higher incidence of stroke or TIA.
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Doença das Coronárias , Insuficiência Cardíaca , Ataque Isquêmico Transitório , Infarto do Miocárdio , Intervenção Coronária Percutânea , Acidente Vascular Cerebral , Humanos , Ponte de Artéria Coronária , Volume Sistólico , Estudos Observacionais como Assunto , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
BACKGROUND: Exploration of adaptive evolution of organisms in response to environmental change can help to understand the evolutionary history of species and the underlying mechanisms of adaptation to local environments, thus guiding future conservation programmes. Before the introduction of Apis mellifera in China, eastern honey bees (Apis cerana) were the only species used for beekeeping in this region. In the mountains of Changbai, populations of A. cerana are considered a distinct ecotype of the species which formed through the distinct selective pressures in this area over time. RESULT: We performed a measure of 300 wing specimens of eastern honey bees and obtained the geometric morphological variation in the wing of A. cerana in Changbai Mountain. A total of 3,859,573 high-quality SNP loci were yielded via the whole-genome resequencing of 130 individuals in 5 geographic regions. CONCLUSION: Corresponding geometric morphology and population genomics confirmed the particularity of the A. cerana in Changbai Mountain. Genetic differentiation at the subspecies level exists between populations in Changbai Mountain and remaining geographic regions, and a significant reduction in the effective population size and an excessive degree of inbreeding may be responsible for a substantial loss of population genetic diversity. Candidate genes potentially associated with cold environmental adaptations in populations under natural selection were identified, which may represent local adaptations in populations. Our study provided insights into the evolutionary history and adaptation of A. cerana in Changbai Mountain, as well as its conservation.
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Metagenômica , Seleção Genética , Adaptação Fisiológica/genética , Animais , Abelhas/genética , China , Análise de Sequência de DNARESUMO
Accurate size analysis of nanoparticles (NPs) is vital for nanotechnology. However, this cannot be realized based on conventional single-nanoparticle collision (SNC) because the current intensity, a thermodynamic parameter of SNC for sizing NPs, is always smaller than the theoretical value due to the effect of NP movements on the electrode surface. Herein, a size-dependent dynamic parameter of SNC, current lifetime, which refers to the time that the current intensity decays to 1/e of the original value, was originally utilized to distinguish differently sized NPs. Results showed that the current lifetime increased with NP size. After taking the current lifetime into account rather than the current intensity, the overlap rates for the peak-type current transients of differently sized Pt NPs (10 and 15 nm) and Au NPs (18 and 35 nm) reduced from 73 and 7% to 45 and 0%, respectively, which were closer to the theoretical values (29 and 0%). Hence, the proposed SNC dynamics-based method holds great potential for developing reliable electrochemical approaches to evaluate NP sizes accurately.
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Nanopartículas Metálicas , Nanopartículas , Eletrodos , NanotecnologiaRESUMO
Single-nanoparticle collision electrochemistry (SNCE) has gradually become an attractive analytical method due to its advantages in analytical detection, such as a fast response, low cost, low sample consumption, and in situ real-time detection of analytes. However, the biological analyte's direct detection based on the SNCE blocking mode has the problems of low sensitivity and specificity. In this work, an SNCE biosensor based on SNCE electrocatalytic strategy was used for the detection of H7N9 AIV. Nucleic acid aptamers were introduced to recognize the target virus (H7N9 AIV). After the recognition event, ssDNA1 was released and hybridized with another ssDNA2. Owing to the nicking endonuclease Nt.AlwI-mediated target nucleic acid cyclic amplification, one virus particle can indirectly induce the release of 4.2 × 106 Au NPs that can be counted by the SNCE electrocatalytic strategy. The high conversion efficiency greatly improved the detection sensitivity, and the detection limit was as low as 24.3 fg/mL. Therefore, the constructed biosensor can achieve a highly sensitive and specific detection of H7N9 AIV and show a great potential in bioanalytical application.
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Técnicas Biossensoriais , Subtipo H7N9 do Vírus da Influenza A , Influenza Aviária , Nanopartículas , Ácidos Nucleicos , Animais , Técnicas Biossensoriais/métodos , EletroquímicaRESUMO
MicroRNA-494 (miR-494) is a small non-coding RNA located in chromosome 14q32.31 and regulates post-transcriptional gene expression by promoting the degradation of its target mRNAs via binding to the 3' untranslated regions (3'UTR). It has been reported that miR-494 plays an important role in the occurrence, development and prognosis of various diseases. Several signaling pathways modulated by miR-494 including the PTEN/PI3K/AKT, nuclear factor κ-B (NF-κB), mitogen-activated protein kinase (MAPK), transforming growth factor-ß (TGF-ß)/SMAD, and Wnt/ß-catenin are associated with physiological regulation and pathological process in many diseases. The stably expression of miR-494 in the blood stream suggests its potential as a biological marker for disease diagnosis, treatment, and prognosis. Based on recent research, we summarize the role and molecular mechanism of miR-494 in disease development and progression. We also discuss its potential as a marker for clinical diagnosis and prognosis of various diseases.
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MicroRNAs , Fosfatidilinositol 3-Quinases , MicroRNAs/genética , MicroRNAs/metabolismo , NF-kappa B/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismoRESUMO
The present study designed and prepared near-infrared responsive sinomenine hydrochloride(SIN) reservoir microneedles and evaluated the feasibility of this type of microneedles in increasing the drug loading and transdermal absorption by characterizing their mechanical properties and in vitro release characteristics.SIN was selected as the model drug, and methoxy poly(ethylene glycol) poly(caprolactone)(mPEG-PCL) copolymers and indocyanine green(ICG) were employed as amphiphilic block copolymers and light inductor to prepare near-infrared responsive nanoparticles.Based on the preparation principle of bubble microneedles, near-infrared responsive SIN reservoir microneedles were designed and prepared.The features of the near-infrared responsive SIN reservoir microneedles were characterized by measuring the morphology, length, mechanical properties, and skin penetration of microneedles.Meanwhile, the drug release performance of reservoir microneedles was evaluated by in vitro release assay.The results showed that the prepared SIN microneedles were conical, with an exposed tip height of about 650 µm.Each needle could load about 0.5 mg of drugs per square centi-meter, and this type of microneedle showed good mechanical properties and performance in skin penetration.The results of the in vitro release assay showed that the 24 h cumulative release per unit area and release rate of the microneedle were 825.61 µg·cm~(-2) and 74.3%, respectively, which indicated that its release kinetics was in line with the first-order kinetic model.This study preliminarily proved that the reservoir microneedle could effectively increase the drug loading with good mechanical properties and release perfor-mance.
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Verde de Indocianina , Morfinanos , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Agulhas , PolietilenoglicóisRESUMO
An ultrasensitive electrochemiluminescence (ECL) biosensor was proposed based on a closed bipolar electrode (BPE) for the detection of alkaline phosphatase (ALP). For most of the BPE-ECL biosensors, an effective signal amplification strategy was the key to enhance the sensitivity of the system. Herein, the signal amplification strategy of the enzyme catalysis was utilized in the BPE-ECL system. Au nanoparticles (NPs) were electrodeposited on the cathode surface of the ITO electrode to improve the stability and sensitivity of the signal. Compared with the previous BPE-ECL biosensors, the sensitivity was increased by at least 3 orders of magnitude. The biosensor showed high sensitivity and specificity of ALP detection with a detection limit of as low as 3.7 aM. Besides, it was further applied to the detection of ALP in different types of cells and successfully realized ALP detection in single Hep G2 cell, which had a huge application prospect in single biomolecule detection or single cell analysis.
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Fosfatase Alcalina/análise , Técnicas Biossensoriais , Técnicas Eletroquímicas , Medições Luminescentes , Análise de Célula Única , Fosfatase Alcalina/metabolismo , Eletrodos , Ouro/química , Células Hep G2 , Humanos , Nanopartículas Metálicas/químicaRESUMO
Back and thigh skin of chickens showed significant differences in the thickness and the feather follicle density and size, which are important traits for slaughtered chickens' appearance. In the present study, global gene expression profiling was conducted in the back and thigh skin of chickens using Microarray technology. The results showed that 676 genes were differentially expressed between back and thigh skin. The expression of the differentially expressed genes (DEGs), including PPP1R3C, IGF1, PTCHD1, HOXB6, FGF9, CAMK4, SHH, BMP8B, FOXN1 and PTGER2, was validated by real-time quantitative polymerase chain reaction (RT-qPCR), and the results were consistent with microarray results. Functional analysis revealed that the DEGs were significantly involved in cell proliferation, differentiation, apoptosis, adhesion and transport process, and the pathways were significantly mapped into the ECM-receptor interaction, peroxisome, focal adhesion, Hedgehog and PPAR signalling pathways. Protein-protein interaction network analysis suggested that signalling pathways related to feathers morphogenesis and development, such as Wnt, FGF, MAPK, SHH and BMP signalling pathways, occupied important positions in the network. Genes involved in these signalling pathways and adhesion molecules might play a vital role in skin and feather follicle development. Further single nucleotide polymorphism (SNP) association analysis of Wnt3A showed that the AC genotype of SNP g.255361 C>A significantly increased the feather follicle density of thigh skin. Our findings may provide new insights on candidate genes and pathways related to skin and feather follicle formation of chickens.
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Galinhas , Plumas , Animais , Galinhas/genética , Perfilação da Expressão Gênica/veterinária , Morfogênese , PeleRESUMO
Pyridine acylhydrazone derivatives of isopimaric acid were synthesized and characterized. The minimum inhibitory concentrations of the compounds against five bacteria were determined and most of the compounds displayed some degree of antibacterial activity. The results showed that antimicrobial activity against Streptococcus pneumoniae improved when halogen atoms were introduced into the isopimaric acid, especially when one bromine atom was introduced in the para-position of isopimaric acid. Compound isopimaric acid (5-bromo pyridine-2-formaldehyde) acylhydrazone exhibited a significant antitumorial activity against hepatocarcioma cells (HepG-2) and breast cancer cells (MDA-MB-231), with inhibition degrees of 74.21% and 70.39%, respectively, at 100 µM.[Formula: see text].
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Fenantrenos , Antibacterianos/farmacologia , Ácidos Carboxílicos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Piridinas/farmacologia , Relação Estrutura-AtividadeRESUMO
BACKGROUND: This study seeks to elucidate the impact of COVID-19 on knowledge, attitude, and infection control behaviors among dentists. METHODS: Changes in knowledge, attitude, and infection control behaviors reported in 2020 (COVID-19 period) were compared to the historical control of the non-COVID-19 period in 2018. A proportional random sampling method was used to select the study samples from 400 dental institutions. The response rate was 69% in 2018 and 62.8% in 2020. A total of 276 dentists in 2018 and 251 dentists in 2020 responded to this questionnaire. Multiple logistic regression was used to assess the associations between factors and recommended infection control practices. RESULTS: High rates of correct COVID-19 knowledge (94.76%), fears of being infected with the virus (94%) and use of personal protective equipment (mask, glove and protection gown; 95%) were reported. We found that knowledge regarding environmental infection control, HIV transmission, and the window of HIV transmission were significantly higher in the post-COVID-19 period compared with the pre-COVID-19 period. High compliance rates of wearing mask, gloves and protection were reported. The number of dentists wearing a hair cap and a protective eye mask/face shield during the pandemic significantly increased compared with that noted before the COVID-19 pandemic. Factors associated with the use of a hair cap and an eye mask/face shield differed between the pre- and post-COVID-19 periods. The factors associated with compliance regarding environment infection control also differed between the pre- and post-COVID-19 periods. CONCLUSION: The significant impact of COVID-19 on the knowledge, attitude, and infection control behaviors among dental care workers was observed in the current study. In particular, the use of hair caps and protective eye mask or face shields as well as environmental disinfection protocols has significantly improved. Trial registration TMU-JIRB: N201804006.
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COVID-19 , Pandemias , Odontólogos , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Controle de Infecções , SARS-CoV-2 , Inquéritos e QuestionáriosRESUMO
Objective: To compare the efficiency of the target gene panel method and whole-exome sequencing (WES) in detecting idiopathic hypogonadotropic hypogonadism (IHH), and select a more suitable gene detection method. METHODS: We selected 24 genes closely related to the molecular pathogenesis of IHH to make up the gene panel, detected the mutation sites in 73 patients with IHH using the panel method, and verified the results of sequencing with the Sanger method. Using the key words "idiopathic hypogonadotropic hypogonadism", we searched databases for relevant literature, calculated the positive rate of IHH detected by WES and compared it with that detected with the panel method. RESULTS: Of the 73 cases of IHH detected with the panel method, 7 were found with pathogenic mutations, including 2 cases of FGFR1, 2 cases of CHD7, 2 cases of KISS1R, and 1 case of NR5A1 mutation. Sanger sequencing showed that the positive rate of the panel method was 9.7%. Of the 1 336 articles retrieved, 5 met the inclusion criteria and were included, in which WES revealed a positive rate of about 30%. CONCLUSIONS: For detection of the diseases with clear mutated genes, the panel method is relatively inexpensive and has a high sequencing depth, while for detection of the diseases with complicated genetic patterns and unclear mutated genes, WES is more efficient. Further studies are needed for choice of the two methods for different purpose of detection./.
Assuntos
Hipogonadismo , Humanos , Hipogonadismo/diagnóstico , Hipogonadismo/genética , Masculino , Sequenciamento do ExomaRESUMO
Scutellariae Radix is a commonly used Chinese medicinal first recorded in the Shennong's Classic of Materia Medica. In the ancient books of traditional Chinese medicine(TCM), Scutellariae Radix is used in two specifications, solid one(Ziqin) and hollow one(Kuqin). In the current rules and regulations of Chinese medicine, Scutellariae Radix is used without the specific requirements for the specifications applied. To clarify the evolution of Scutellariae Radix specifications and analyze the current specifications of Scutellariae Radix pieces, the present study reviews the Scutellariae Radix from ancient literature, modern rules and regulations, and differences between Ziqin and Kuqin in composition, efficacy, and transformation mechanism. According to the research on ancient books, Kuqin is effective in clearing the fire of the upper energizer, and Ziqin in purging the heat of the lower energizer. Modern studies have revealed that Kuqin and Ziqin are significantly different in chemical components, and Ziqin and Kuqin target the colon and lung, respectively, which are consistent with the relevant records in ancient books. The review study suggests that the two specifications of Scutellariae Radix are reasonable since they can facilitate the precise treatment of Scutellariae Radix.