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KEY MESSAGE: We demonstrated a short-cycle B. napus line, Sef1, with a highly efficient and fast transformation system, which has great potential in large-scale functional gene analysis in a controlled environment. Rapeseed (Brassica napus L.) is an essential oil crop that accounts for a considerable share of global vegetable oil production. Nonetheless, studies on functional genes of B. napus are lagging behind due to the complicated genome and long growth cycle, this is largely due to the limited availability of gene analysis and modern genome editing-based molecular breeding. In this study, we demonstrated a short-cycle semi-winter-type Brassica napus 'Sef1' with very early-flowering and dwarf phenotype, which has great potential in large-scale indoor planting. Through the construction of an F2 population of Sef1 and Zhongshuang11, bulked segregant analysis (BSA) combined with the rape Bnapus50K SNP chip assay method was used to identify the early-flowering genes in Sef1, and a mutation in BnaFT.A02 was identified as a major locus significantly affecting the flowering time in Sef1. To further investigate the mechanism of early flowering in Sef1 and discover its potential in gene function analysis, an efficient Agrobacterium-mediated transformation system was established. The average transformation efficiency with explants of hypocotyls and cotyledons was 20.37% and 12.8%, respectively, and the entire transformation process took approximately 3 months from explant preparation to seed harvest of transformed plants. This study demonstrates the great potential of Sef1 for large-scale functional gene analysis.
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Brassica napus , Brassica napus/genética , Genômica , Fenótipo , Análise de Sequência com Séries de Oligonucleotídeos , Ambiente ControladoRESUMO
BACKGROUND: Nuts have been found to have beneficial effects on some diseases, including cardiovascular disease and cancer, in several studies. However, there are few studies to show the effects of nuts on chronic kidney disease (CKD). Thus, we conducted this study to examine the association between the consumption frequency of nuts and the prevalence and mortality of CKD among adults in the USA. METHODS: We analyzed data from 6,072 individuals (aged ≥20 years) who participated in the NHANES 2003-2006 following the scheduled procedure. Data on death were provided by the CDC. A logistic regression model was used to evaluate the association between nut consumption frequency and the prevalence of CKD. A Cox proportional hazards regression model was performed to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between nut consumption frequency and all-cause mortality and cardiovascular mortality in the CKD and non-CKD populations. RESULTS: Consuming nuts 1-6 times per week was associated with a lower prevalence of CKD (model 3: OR: 0.67; 95% CI: 0.49-0.91). In addition, higher nut consumption was significantly associated with lower all-cause and cardiovascular mortality in the non-CKD population. For the CKD population, a consistently significant inverse association could be seen between consuming nuts 1-6 per week and all-cause mortality (model 3: HR: 0.63; 95% CI: 0.47-0.86). No groups showed a significant difference in cardiovascular mortality compared with the reference in the full model. CONCLUSION: We recommend the CKD population to have an adequate intake of nuts 1-6 times per week, while the consumption frequency can be more flexible for the non-CKD. Further prospective studies should be conducted to confirm this conclusion.
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Doenças Cardiovasculares , Insuficiência Renal Crônica , Adulto , Doenças Cardiovasculares/epidemiologia , Dieta , Humanos , Inquéritos Nutricionais , Nozes , Estudos Prospectivos , Insuficiência Renal Crônica/epidemiologia , Fatores de Risco , Estados Unidos/epidemiologiaRESUMO
BACKGROUND: Both simulation-based training and video-based training serve as educational adjuncts for learning TEE among medical students. In the present study, we hypothesized that simulation-based training would better enhance the performance of medical students in the interpretation of 20 cross-sectional views compared to video-based training. METHODS: A total of 120 4th-year undergraduate medical students were enrolled in the present study. The study began with a pre-test of all the participants, followed by a 90-min theoretical lecture and a post-test. Subsequently, the participants were randomly divided into the video-based group (Group V) and simulation-based group (Group S). Next, Group V received 60 min of TEE video learning, while Group S received 60 min of TEE simulator training. After the respective training, both the groups undertook the retention-test 1 and retention-test 2, 1 week and 1 month later, respectively. The performance for each test was evaluated by five views, which were selected randomly and, respectively, from a set of 20 cross-sectional views. The primary outcome was the performance of the retention-test 1. Secondary outcomes included: (1) comparison the performances of the pre-test, post-test, and retention-test 2 between two groups; (2) comparison the performances of pre-test and post-test in the same group; (3) comparison the performances of retention-test 1, and retention-test 2 in the same group. RESULTS: Better performances were observed in Group S in both retention-test 1 (Group V: 63.2 [52.6, 77.6] vs. Group S: 89.5 [68.4, 100.0], P < 0.001) and retention-test 2 (Group V: 58.0 [48.0, 72.0] vs. Group S: 74.0 [64.0, 80.0], P < 0.001) compared to Group V. No statistically significant differences were observed in the performances of pre-test (Group V: 8.3 [4.2, 12.5] vs. Group S: 8.3 [4.2, 12.5], P = 0.825) or post-test (Group V: 46.2 [38.5, 57.7] vs. Group S: 44.2 [38.5, 56.7], P = 0.694) between the two groups. The improvement had been observed in the post-test, compared with pre-test in the same group, respectively (Group V in post-test: 46.2 [38.5, 57.7] vs. Group V in pre-test: 8.3 [4.2, 12.5], P < 0.001; Group S in post-test: 44.2 [38.5, 56.7] vs. Group S in pre-test: 8.3 [4.2, 12.5], P < 0.001). However, the performance in retention-test 2 was significantly reduced, compared with retention-test 1 in the same group, respectively (Group V in retention-test 2: 58.0 [48.0, 72.0] vs. Group V in retention-test 1: 63.2 [52.6, 77.6] P = 0.005; Group S in retention-test 2: 74.0 [64.0, 80.0] vs. Group S in retention-test 1: 89.5 [68.4, 100.0], P < 0.001). CONCLUSIONS: Following a 90-min theoretical lecture, simulation-based training better enhanced the performance of medical students in the interpretation and short-term retention of 20 cross-sectional views compared to video-based training. TRIAL REGISTRATION: http://www.chictr.org.cn ( ChiCTR2000033519 , 3/June/2020).
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Treinamento por Simulação , Estudantes de Medicina , Competência Clínica , Estudos Transversais , Ecocardiografia , Avaliação Educacional , Humanos , Estudos ProspectivosRESUMO
A novel core-shell magnetic nano-adsorbent with surface molecularly imprinted polymer coating was fabricated and then applied to dispersive micro-solid-phase extraction followed by determination of rhodamine 6G using high-performance liquid chromatography. The molecularly imprinted polymer coating was prepared by copolymerization of dopamine and m-aminophenylboronic acid (functional monomers), in the presence of rhodamine 6G (template). The selection of the suitable functional monomers was based on the interaction between different monomers and the template using the density functional theory. The ratios of the monomers to template were further optimized by an OA9 (3(4) ) orthogonal array design. The binding performances of the adsorbent were evaluated by static, kinetic, and selective adsorption experiments. The results reveal that the adsorbent possesses remarkable affinity and binding specificity for rhodamine 6G because of the enhanced Lewis acid-base interaction between the B(Ш) embedded in the imprinted cavities and the template. The nano-adsorbent was successfully applied to dispersive micro-solid-phase extraction coupled to high-performance liquid chromatography for the trace determination of rhodamine 6G in samples with a detection limit of 2.7 nmol/L. Spiked recoveries ranged from 93.0-99.1, 89.5-92.7, and 86.9-105% in river water, matrimony vine and paprika samples, respectively, with relative standard deviations of less than 4.3%.
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Nanopartículas de Magnetita/química , Impressão Molecular , Polímeros/química , Teoria Quântica , Rodaminas/análise , Microextração em Fase Sólida , Cromatografia Líquida de Alta Pressão , Dióxido de Silício/químicaRESUMO
OBJECTIVES: To estimate the safety and effectiveness of emergent transjugular intrahepatic portosystemic shunt (TIPS) creation for acute variceal bleeding (AVB) in cirrhotic patients with hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Data of thirty-three patients with AVB and HCC undergoing emergent TIPS creation from January 2016 to January 2022 were enrolled and were retrospectively analyzed. The primary outcomes were the safety of emergent TIPS creation, the bleeding control rate, and the rebleeding rate. The secondary outcomes included overall survival (OS), liver function, overt hepatic encephalopathy (HE), and shunt dysfunction. RESULTS: Emergent TIPS creation was technically successful in 33 patients (100%) and one (3.0%) patient suffered a major procedure-related adverse event. The control rate of bleeding (within 5 days) was 100%. During a median follow-up period of 26.3 months, rebleeding occurred in 6 (18.2%) patients. The median OS was 20.0 months. The 6-week and 1-year survival rates were 87% and 65%, respectively. Laboratory tests showed no significant impairment of liver function following TIPS creation. The incidences of overt HE and shunt dysfunction were 24.2% and 6.1%, respectively. CONCLUSION: Emergent TIPS creation is feasible and effective for treatment of AVB in cirrhotic patients with HCC.
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Carcinoma Hepatocelular , Varizes Esofágicas e Gástricas , Neoplasias Hepáticas , Derivação Portossistêmica Transjugular Intra-Hepática , Humanos , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/cirurgia , Varizes Esofágicas e Gástricas/complicações , Varizes Esofágicas e Gástricas/cirurgia , Hemorragia Gastrointestinal/cirurgia , Hemorragia Gastrointestinal/complicações , Estudos Retrospectivos , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/cirurgia , Recidiva Local de Neoplasia , Cirrose Hepática/complicações , Resultado do TratamentoRESUMO
BACKGROUND: Renal tertiary lymphoid structures (TLSs) are involved in renal pathology and prognosis of IgA nephropathy (IgAN). CD30 and its ligands participate in the formation of renal TLSs. However, the relationship between circulating CD30 and renal prognosis is unclear. The objective of this study was to evaluate the relationship between circulating CD30 and prognosis in patients with IgAN. METHODS: We conducted a retrospective study including 351 patients with biopsy proved IgAN. We collected clinical and pathologic features at the time of biopsy and recorded renal follow-up outcomes. Circulating CD30 levels in IgAN patients at the time of biopsy were measured via enzyme-linked immunosorbent assay (ELISA). The association between elevated CD30 levels and the composite endpoint (defined as a ≥ 50 % decline in eGFR from baseline, end-stage renal disease, or death) was investigated using Cox regression analysis. RESULTS: During a median follow-up period of 5.12 years, 44 (12.5 %) patients in the cohort reached the composite endpoint. Kaplan-Meier survival curve analysis revealed a significant association between higher circulating CD30 levels and a poorer renal prognosis (log-rank P < 0.001). Cox regression analysis showed that high CD30 was an independent factor for the composite endpoints in multivariable-adjusted models (HR 3.397, 95 % CI: 1.230-9.384, P = 0.018). These associations were also observed in a subgroup of patients with concomitant renal TLSs formation (10.443, 95 % CI: 1.680-65.545, P = 0.012), proteinuria > 1 g/d (HR 12.287, 95 % CI: 1.499-100.711, P = 0.019), and female patients (HR 22.372, 95 % CI: 1.797-278.520, P = 0.016). CONCLUSION: Elevated level of circulating CD30 is an independent risk factor for renal disease progression in patients with IgAN.
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Glomerulonefrite por IGA , Estruturas Linfoides Terciárias , Humanos , Feminino , Glomerulonefrite por IGA/diagnóstico , Glomerulonefrite por IGA/patologia , Estudos Retrospectivos , Estruturas Linfoides Terciárias/patologia , Progressão da Doença , Rim/patologia , Prognóstico , Taxa de Filtração GlomerularRESUMO
Isoflurane (ISO) has been widely used in clinical anesthesia, and exposure to ISO leads to cognitive dysfunction. Our paper aimed to investigate the effect of miR-128-3p on cognitive impairment, inflammation, and oxidative stress elicited by ISO anesthesia in Sprague-Dawley (SD) rats. The SD rats were treated with ISO to mimic the ISO-injured situation, and the concentration of miR-128-3p was quantified utilizing real-time PCR. The miR-128-3p's impacts in ISO-engendered rat models on the respects of inflammatory condition and oxidative activities were measured by the commercial kits. The Morris water maze test was adopted to measure the neuro-function regarding miR-128-3p. Additionally, the target was tested by the alternation of luciferase activity. The irritation of ISO suppressed miR-128-3p expression in rats, which was enhanced by the injection of miR-128-3p agomir. The adverse roles of ISO on inflammation, oxidative stress, and cognitive disorders were partially abrogated by an increment of miR-128-3p. A miR-128-3p's interconnection with specificity protein 1 (SP1) was pinpointed, and aggrandized mRNA levels of SP1 were found under ISO state. MiR-128 acted as a regulator in ISO damage in the respects of cognition, inflammation, and oxidative stress. The SP1's link of miR-128-3p was showcased.
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Anestesia , Isoflurano , MicroRNAs , Síndromes Neurotóxicas , Animais , Apoptose , Inflamação/induzido quimicamente , Isoflurano/toxicidade , MicroRNAs/metabolismo , Síndromes Neurotóxicas/etiologia , Ratos , Ratos Sprague-DawleyRESUMO
Background: Chronic kidney disease (CKD) in women is often accompanied by hormone disorders such as sex hormones, and most women with CKD are in the post-menopausal age group. Due to the close relationship between menopause and sex hormones, we aimed to explore the association between early menopause and CKD in post-menopausal women, and the influence of early menopause on longevity in the CKD population. Methods: Information regarding 4,945 post-menopausal women was extracted from the database of the National Health and Nutrition Examination Survey (NHANES) 1999-2014, and then divided into 4 groups according to the type of menopause (natural or surgical) and early menopause (menopause at age <45) or not. The association between early menopause and CKD prevalence was examined using multivariable logistic regression, while we used multivariable Cox proportional hazards models to investigate the possible relationship between early menopause and all-cause mortality in CKD and non-CKD populations. The differences in the levels of sex hormones between women with and without CKD were also explored. Results: Compared with women with natural menopause at age ≥45, women experiencing early natural menopause had a higher risk of CKD [OR = 1.26 (1.01-1.56)]. Similarly, as compared to women with surgical menopause at age ≥ 45, women in the early surgical menopause group were more likely to have CKD [OR = 1.38 (1.05-1.81)]. In addition, early surgical menopause was associated with higher mortality in the non-CKD group [HR = 1.62 (1.06-2.49)], but not in the CKD group. Women with CKD had a higher level of luteinizing hormone and follicle-stimulating hormone, combined with a lower level of testosterone and estradiol than the non-CKD women. Conclusion: Both early natural and surgical menopause were associated with a higher risk of CKD. Early surgical menopause was a hazard factor for survival in the non-CKD group, but not in the CKD group. Further research is required to understand the mechanisms.
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The totally implantable venous access device (TIVAD) has been widely used in clinical nursing work in China. The use of TIVAD has significantly improved the safety of venous access and reduced the pain caused by a repeated puncture; however, it may also bring with it varying degrees of complications associated with the long-term insertion of TIVAD and the maintenance quality of the venous access. Standard maintenance of the venous access for TIVAD is very important for reducing complications and improving the efficacy and patient's quality of life. This consensus briefly describes the fundamental knowledge and operating procedures of TIVAD while focusing on the evaluation and management of perioperative nursing, the observation and treatment of complications, the operation methods, and precautions for maintenance of venous access, as well as health education. This agreement seeks to standardize the nursing care of TIVAD patients in China.
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Cateterismo Venoso Central , Cateteres de Demora , Consenso , Humanos , Próteses e Implantes , Qualidade de VidaRESUMO
BACKGROUND: At present, liver cancer deaths of China account for about half of the global liver cancer deaths. The most common physiological change in anesthesia surgery for liver cancer is liver ischemia-reperfusion injury (LIRI). METHODS: The Chinese and English medical databases were searched using a combination of the following search terms: "propofol", "liver cancer", "anesthesia surgery", and "ischemia reperfusion injury" in Chinese or English language, respectively. The articles taking patients received propofol intravenous anesthesia surgery for LIRI in the experimental group and patients received intravenous anesthesia with non-propofol drugs for LIRI in the control group were searched. Rev Man 5.3 software was used for meta-analysis. RESULTS: A total of 18 articles were included, and most were considered to have low-risk bias (that is, medium- and high-quality publications). The meta-analysis results indicated that the superoxide dismutase (SOD) levels from the blockage of the hepatic hilum (B-HH) to the 15-minute opening of the hepatic hilum (O-HH) showed a mean deviation (MD) of -0.33 nU/mL and 95% confidential interval (CI) of -1.81 to 1.15 nmol/L (P<0.05). The levels of malondialdehyde (MDA) from B-HH to O-HH showed a MD of 1.80 nmol/L and 95% CI of 1.53 to 2.07 nmol/l (P<0.05). The MD of alanine transaminase (ALT) levels from B-HH to O-HH was 8.24 IU/L with 95% CI 6.43 to 10.06 IU/L (P<0.05). The MD of aspartate transaminase (AST) levels from B-HH to O-HH was -11.73 IU/L with 95% CI -14.04 to -9.43 IU/L (P<0.05). The RevMan5.3 software was used to draw the funnel chart for each indicator from B-HH to OHH. The results revealed that the circles in some articles were concentrated on the midline and were basically symmetrical with the midline, indicating that the research accuracy was high and there was no bias in publication. DISCUSSION: This meta-analysis confirmed that propofol exerted a protective effect on LIRI during anesthesia surgery with hepatic hilar blockade.
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Anestesia , Carcinoma Hepatocelular , Neoplasias Hepáticas , Propofol , Traumatismo por Reperfusão , Carcinoma Hepatocelular/cirurgia , China , Humanos , Fígado , Neoplasias Hepáticas/cirurgia , Propofol/uso terapêutico , Traumatismo por Reperfusão/prevenção & controleRESUMO
BACKGROUND: This study aimed to compare the effects of general anesthesia (GA) combined with continuous paravertebral block (CPVB) in breast cancer surgery via systematic review and meta-analysis, in order to provide a theoretical basis for the clinical use of CPVB surgical analgesia. METHODS: A search of the PubMed, Embase, Medline, Ovid, Springer, and Web of Science databases was conducted to screen clinical trials on GA + CPVB for breast cancer surgery published before December 31, 2020. The Cochrane Handbook for Systematic Reviews of Intervention 5.0.2 was adopted for bias risk assessment, and Review Manager 5.3 software (RevMan, The Cochrane Collaboration, http://tech.cochrane.org/revman) was applied for meta-analysis of the literature. RESULTS: A total of 15 studies that satisfied the requirements were included, involving a total of 1,435 research subjects. The results of our meta-analysis showed the following: the visual analogue scale (VAS) score of the observation group (group A) was significantly reduced [mean difference (MD) =-0.68; 95% confidential interval (CI): -1.04 - -0.33; Z=3.80; P=0.0001]; the level of monocyte chemoattractant protein -1 (MCP-1) was notably decreased (MD =-18.64; 95% CI: -29.68 - -7.61; Z=3.31; P=0.0009); the level of tumor necrosis factor-α (TNF-α) was markedly lower (MD =-1.89; 95% CI: -2.66 - -1.13; Z=4.87; P<0.00001); the interleukin-6 (IL-6) level was obviously reduced (MD =-12.10; 95% CI: -19.22 - -4.99; Z=3.33; P=0.0009); and the incidence of postoperative adverse reactions was substantially decreased (MD = 0.16; 95% CI: 0.07-0.36; Z=4.47; P<0.00001). Compared with group B, the differences of the above five indicators showed statistical significance. In addition, the heart rate (HR) (MD =-1.56; 95% CI: -6.20 - 3.08; Z=0.66; P=0.51), mean arterial pressure (MAP) (MD = 4.66; 95% CI: -0.12 -9.43; Z=1.91; P=0.06), Ramsay score (MD =0.44; 95% CI: -0.06-0.93; Z=1.73; P=0.08) of patients in group A showed no statistical differences compared to group B. CONCLUSIONS: GA + CPVB applied to breast cancer surgery for analgesia can reduce the levels of MCP-1, TNF-α, and IL-6 in patients, thereby providing good postoperative analgesia. Therefore, GA + CPVB could effectively reduce the incidence of pain and adverse reactions in patients, and is effective for analgesia in breast cancer surgery.
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Background: Epicardial adipose tissue (EAT) has been linked with the pathogenesis of heart failure (HF). Limited data have been reported about the clinical value of EAT for cardiac resynchronization therapy (CRT) in non-ischemic systolic HF. We aimed to explore the values of EAT measured from CT to predict the response to CRT in patients with non-ischemic systolic HF. Methods: Forty-one patients with CRT were consecutively recruited for our study. All patients received both gated resting Single Photon Emission CT (SPECT) myocardial perfusion imaging (MPI) and dual-source multi-detector row CT scans. EAT thickness was assessed on both the parasternal short and horizontal long-axis views. The area of EAT was calculated at the left main coronary artery level. Left ventricular systolic mechanical dyssynchrony (LVMD) was measured by phase standard deviation (PSD) and phase histogram bandwidth (PBW). The definition of CRT response was an improvement of 5% in left ventricular ejection fraction (LVEF) at 6 months after CRT implantation. Results: After 6 months of follow-up, 58.5% (24 of 41) of patients responded to CRT. A greater total perfusion deficit (TPD) was observed in the left ventricle, and a narrower QRS complex was observed in the nonresponse group than in the response group (p < 0.05). Meanwhile, the systolic PSD and systolic PBW were statistically greater in the CRT group with no response than in the response group (p < 0.05). Meanwhile, the baseline QRS duration, TPD, systolic PSD, systolic PBW, EAT thicknesses of the left ventricular (LV) apex, right atrioventricular (AV) groove, and left AV groove were all significantly related to the CRT response in the univariate logistic regression analysis. Furthermore, the QRS duration and EAT thicknesses of the right AV groove and left AV groove were independent predictors of CRT response in the multivariate logistic regression analysis. Conclusions: The EAT thickness of the left AV groove in patients with non-ischemic systolic HF is associated with the TPD of LV and LV systolic dyssynchrony. The EAT thickness of the AV groove has a good predictive value for the CRT response in patients with non-ischemic systolic HF.
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BACKGROUND: The hepatotoxicity of Chinese herbal medicine (CHM) is an important reason for its restrictive application. Psoraleae Fructus (PF), a commonly used CHM for treatment of osteoporosis and vitiligo etc., has caused serious concern due to the frequent occurrence of liver injury incidents. To date, its hepatotoxic equivalent markers (HEMs) and potential mechanisms are still unclear. PURPOSE: To discover and validate the HEMs of PF and further explore the potential mechanisms of hepatotoxicity. METHODS: Multi-parametric cellular imaging was performed by high content screening, and multi-component quantitative profiling was conducted by ultra-high performance liquid chromatography coupled with triple-quadrupole mass spectrometry. The correlations between hepatotoxic features and component contents were modeled by chemometrics including partial least square regression, back propagation-artificial neural network, and hierarchical cluster analysis. Then the candidate HEMs of PF were screened out and subjected to hepatotoxic equivalence assessment in primary hepatocytes, zebrafish, and mice, and the hepatotoxic mechanisms of PF were investigated. RESULTS: The chemical combination of psoralen and isopsoralen was discovered as the HEMs of PF through pre-screening and verifying process. PF was demonstrated to induce oxidative stress, mitochondrial dysfunction and cellular apoptosis. CONCLUSIONS: This study not only provides a rational strategy for screening HEMs from CHMs like PF, but also contributes to understanding the underlying mechanisms of PF hepatotoxicity.
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Medicamentos de Ervas Chinesas , Animais , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/toxicidade , Frutas , Fígado , Camundongos , Peixe-ZebraRESUMO
A label-free and selective sensor was established for uranyl ion (UO22+) detection based on a UO22+-dependent DNAzyme and liquid crystals (LCs). In the presence of UO22+, the substrate chains can be cleaved at the rA site by the DNAzyme strands. The cleaved products released from the DNAzyme strand will hybridize with the capture probes that are fixed on the LC sensing substrate to form double strands. The formation of double strands would disturb the original orientation and induce the rearrangement of liquid crystal molecules, resulting in the polarization images changing from uniform black to bright. Attributed to the specificity of the DNAzyme and the optical signal of the LC, a highly selective and label-free method was established with a detection limit of 25 nM. This approach showed satisfactory analytical performance and offered an inspiring platform for detecting other radioactive elements.
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Técnicas Biossensoriais , DNA Catalítico , Cristais LíquidosRESUMO
BACKGROUND AND OBJECTIVE: Long-acting nociceptive-selective regional anesthesia has remained an elusive clinical goal. We aspired to identify a novel compound that would produce nociceptive-selective regional anesthesia through the transient receptor potential vanilloid 1 (TRPV1) channels. METHODS: We designed and synthesized a novel compound (LL-a) that penetrates the cell membrane through TRPV1 channels and binds to voltage-gated sodium channels. The regional anesthetic effect of LL-a was evaluated in a rodent sciatic nerve block model. Electrophysiological recording was applied to test the inhibition of LL-a on voltage-gated sodium channel currents. RESULTS: LL-a inhibited sodium channel currents on the dorsal root ganglion neurons of mice and this action was diminished by TRPV1 channel knockout. In a sciatic nerve block model of a rat, 0.2% and 0.4% (w/v) LL-a produced selective sensory block with median (IQR) durations of 42.0 (24.0, 48.0) and 72.0 (69.0, 78.0) hours, respectively. No motor block was found for 0.2% LL-a. 0.4% LL-a produced a motor block with a median (IQR) duration of 3.0 (0.0, 6.0) hours. This selective sensory block was not observed on TRPV1 knockout mice. As a positive control, 0.5% and 0.75% levobupivacaine produced a non-selective sciatic nerve block with median (IQR) durations of 2.8 (2.6, 2.8) and 3.8 (3.8, 4.8) hours, respectively. No systemic or local irritation was observed during injection of LL-a and sensory and motor function completely recovered for all the animals. CONCLUSIONS: LL-a is a potential novel local anesthetic for long-lasting nociceptive-selective analgesia.
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Anestesia por Condução , Canais de Potencial de Receptor Transitório , Anestésicos Locais/toxicidade , Animais , Camundongos , Nociceptividade , Ratos , Roedores , Nervo Isquiático , Canais de Cátion TRPV/genéticaRESUMO
Seeds are the basis for forest regeneration. To examine the composition and spatio-temporal dynamics of seed rains, a total of 150 seed traps of 0.5 m2 were installed in a 25 hm2 broad-leaved Korean pine (Pinus koraiensis) mixed forest plot in Changbai Mountains. With a total of 252 collections from May 2006 to September 2017, we collected 764299 mature and immature seeds which were belonged to 27 species, 17 genera, and 12 families. More than 90% of all collected seeds (704231 seeds) were from 13 canopy species. Seeds of four tree species, including Tilia amurensis, Fraxinus mandschurica, Acer mono, and Acer pseudo-sieboldianum could be collected every year from each trap. Mast-seeding was found in every canopy layer, but it happened one to two years earlier in the overstorey layer than midstorey and understorey layer. Almost all species produced seeds in autumn, with considerable spatiotemporal variation. Generally, the spatial variation of seeds was larger than temporal variation. Compared with annual variation coefficient of seeds in tropical forest of the Barro Colorado Island (BCI) and subtropical evergreen forest in the Gutianshan, annual variation coefficient of seeds in Changbai Mountains was higher, which supported the hypothesis that annual variation in seed rains would be lower in the tropics than that in higher latitudes.
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Florestas , Pinus , China , Ecossistema , Sementes , ÁrvoresRESUMO
An innovative electrochemical sensor was fabricated for the sensitive and selective determination of tinidazole (TNZ), based on a carbon paste electrode (CPE) modified with multi-walled carbon nanotubes (MWCNTs) and boron-embedded molecularly imprinted composite membranes (B-MICMs). Density functional theory (DFT) calculations were carried out to investigate the utility of template-monomer interactions to screen appropriate monomers for the rational design of B-MICMs. The distinct synergic effect of MWCNTs and B-MICMs was evidenced by the positive shift of the reduction peak potential of TNZ at B-MICMs/MWCNTs modified CPE (B-MICMs/MWCNTs/CPE) by about 200â¯mV, and the 12-fold amplification of the peak current, compared with a bare carbon paste electrode (CPE). Moreover, the coordinate interactions between trisubstituted boron atoms embedded in B-MICMs matrix and nitrogen atoms of TNZ endow the sensor with advanced affinity and specific directionality. Thereafter, a highly sensitive electrochemical analytical method for TNZ was established by different pulse voltammetry (DPV) at B-MICMs/MWCNTs/CPE with a lower detection limit (1.25â¯×â¯10-12â¯molâ¯L-1) (S/Nâ¯=â¯3). The practical application of the sensor was demonstrated by determining TNZ in pharmaceutical and biological samples with good precision (RSD 1.36% to 3.85%) and acceptable recoveries (82.40%-104.0%).
Assuntos
Antitricômonas/sangue , Antitricômonas/urina , Boro/química , Impressão Molecular , Nanotubos de Carbono/química , Tinidazol/sangue , Tinidazol/urina , Antitricômonas/análise , Carbono/química , Técnicas Eletroquímicas/métodos , Eletrodos , Humanos , Limite de Detecção , Membranas Artificiais , Polímeros/química , Tinidazol/análiseRESUMO
An innovative electrochemical sensor, based on a carbon paste electrode (CPE) modified with graphene (GR) and a boron-embedded duplex molecularly imprinted hybrid membrane (B-DMIHM), was fabricated for the highly sensitive and selective determination of lamotrigine (LMT). Density functional theory (DFT) was employed to study the interactions between the template and monomers to screen appropriate functional monomers for rational design of the B-DMIHM. The distinct synergic effect of GR and B-DMIHM was evidenced by the positive shift of the reduction peak potential of LMT at B-DMIHM/GR modified CPE (B-DMIHM/GR/CPE) by about 300mV, and the 13-fold amplification of the peak current, compared to a bare carbon paste electrode (CPE). The electrochemical reduction mechanism of lamotrigine was investigated by different voltammetric techniques. It was illustrated that square wave voltammetry (SWV) was more sensitive than different pulse voltammetry (DPV) for the quantitative analysis of LMT. Thereafter, a highly sensitive electroanalytical method for LMT was established by SWV at B-DMIHM/GR/CPE with a good linear relationship from 5.0×10-8 to 5.0×10-5 and 5.0×10-5 to 3.0×10-4molL-1 with a lower detection limit (1.52×10-9molL-1) based on the lower linear range(S/N=3). The practical application of the sensor was demonstrated by determining the concentration of LMT in pharmaceutical and biological samples with good precision (RSD 1.04-4.41%) and acceptable recoveries (92.40-107.0%).
Assuntos
Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Grafite/química , Triazinas/isolamento & purificação , Boro/química , Eletrodos , Lamotrigina , Limite de Detecção , Impressão Molecular , Polímeros/química , Triazinas/químicaRESUMO
A novel electrochemical sensor based on duplex molecularly imprinted polymer (DMIP) hybrid film modified carbon paste electrode (CPE) has been developed for highly sensitive and selective determination of metronidazole (MNZ). A conductive poly(anilinomethyltriethoxysilane) film is firstly electrodeposited on the surface of a CPE, and then a molecularly imprinted polysiloxane (MIPS) membrane is covalently covered on the film via sol-gel process. The as-constructed DMIP hybrid film, combining the advantages of MIPS and conducting MIP, can make feasible the direct and efficient signal transformation between the target analyte and the transducer, as well as enhance the imprinting recognition capability, mass transfer efficiency and the detection sensitivity. Under optimized conditions, the reduction peak currents of MNZ are linear to MNZ concentrations in the range from 4.0×10(-7) to 2.0×10(-4) molL(-1) with a detection limit of 9.1×10(-8)molL(-1). The RSD values vary from 2.9% to 4.7% for intra-day and from 3.4% to 4.2% for inter-day precision. The DMIP-based sensor has been successfully applied for the determination of MNZ in biological and pharmaceutical samples. The accuracy and reliability of the method is further confirmed by high performance liquid chromatography.
Assuntos
Anti-Infecciosos/sangue , Anti-Infecciosos/urina , Técnicas Biossensoriais/instrumentação , Metronidazol/sangue , Metronidazol/urina , Impressão Molecular , Siloxanas/química , Anti-Infecciosos/análise , Carbono/química , Técnicas Eletroquímicas/instrumentação , Eletrodos , Desenho de Equipamento , Humanos , Limite de Detecção , Metronidazol/análiseRESUMO
In arid and semi-arid areas, plant physiological responses to water availability depend largely on the intensity and frequency of rain events. Knowledge on the responses of xerophytic plants to rain events is important for predicting the structure and functioning of dryland ecosystems under changing climate. The sap flow of Hedysarum scoparium in the Mu Us Sand Land was continuously measured during the growing season of 2012 and 2013. The objectives were to quantify the dynamics of sap flow under different weather conditions, and to examine the responses of sap flow to rain events of different sizes. The results showed that the daily sap flow rates of H. scoparium were lower on rainy days than on clear days. On clear days, the sap flow of H. scoparium showed a midday plateau, and was positively correlated with solar radiation and relative humidity. On rainy days, the sap flow fluctuated at low levels, and was positively correlated with solar radiation and air temperature. Rain events not only affected the sap flow on rainy days through variations in climatic factors (e.g., solar radiation and air temperature), but also affected post-rainfall sap flow velocities though changes in soil moisture. Small rain events (<20 mm) did not change the sap flow, whereas large rain events (>20 mm) significantly increased the sap flow on days following rainfall. Rain-wetted soil conditions not only resulted in higher sap flow velocities, but also enhanced the sensitivity of sap flow to solar radiation, vapor pressure deficit and air temperature.