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1.
Respir Res ; 22(1): 94, 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33789673

RESUMO

BACKGROUND: Pneumonia is the most frequently encountered postoperative pulmonary complications (PPC) after orthotopic liver transplantation (OLT), which cause high morbidity and mortality rates. We aimed to develop a model to predict postoperative pneumonia in OLT patients using machine learning (ML) methods. METHODS: Data of 786 adult patients underwent OLT at the Third Affiliated Hospital of Sun Yat-sen University from January 2015 to September 2019 was retrospectively extracted from electronic medical records and randomly subdivided into a training set and a testing set. With the training set, six ML models including logistic regression (LR), support vector machine (SVM), random forest (RF), adaptive boosting (AdaBoost), extreme gradient boosting (XGBoost) and gradient boosting machine (GBM) were developed. These models were assessed by the area under curve (AUC) of receiver operating characteristic on the testing set. The related risk factors and outcomes of pneumonia were also probed based on the chosen model. RESULTS: 591 OLT patients were eventually included and 253 (42.81%) were diagnosed with postoperative pneumonia, which was associated with increased postoperative hospitalization and mortality (P < 0.05). Among the six ML models, XGBoost model performed best. The AUC of XGBoost model on the testing set was 0.734 (sensitivity: 52.6%; specificity: 77.5%). Pneumonia was notably associated with 14 items features: INR, HCT, PLT, ALB, ALT, FIB, WBC, PT, serum Na+, TBIL, anesthesia time, preoperative length of stay, total fluid transfusion and operation time. CONCLUSION: Our study firstly demonstrated that the XGBoost model with 14 common variables might predict postoperative pneumonia in OLT patients.

2.
Zhongguo Zhen Jiu ; 41(3): 288-92, 2021 Mar 12.
Artigo em Chinês | MEDLINE | ID: mdl-33798312

RESUMO

OBJECTIVE: To observe the efficacy of acupuncture combined with Heixiaoyao powder for children with cerebral palsy (liver-qi stagnation, spleen-kidney deficiency syndrome) and its effect on serum immune indexes and nerve growth related protein. METHODS: A total of 180 children with cerebral palsy were randomly divided into a combined group (60 cases, 2 cases dropped off), an acupuncture group (60 cases, 4 cases dropped off) and a Chinese medication group (60 cases, 5 cases dropped off). On the basis of conventional treatment, the children in the combined group were treated with acupuncture [Baihui (GV 20), Sishencong (EX-HN 1), Shenting (GV 24), Benshen (GB 13), 30 min each time, twice a day] and Heixiaoyao powder; the children in the acupuncture group were treated with acupuncture, and the children in the Chinese medication group were treated with Heixiaoyao powder, the treatment was same with the combined group. All the children were treated for 6 consecutive days and rest for 1 day, totaling for 8 weeks. The Gesell developmental schedules (GDS) and TCM symptom scores were recorded before treatment, after treatment and at 3-month, 6-month and 12-month follow-up visit; the serum immune indexes (IgA, IgG and IgM) and nerve growth related protein [myelin basic protein (MBP), high mobility group box-1 (HMGB1), neuronspecific enolase (NSE)] were detected before and after treatment. The clinical efficacy of each group was evaluated. RESULTS: The total effective rate was 91.4% (53/58) in the combined group, which was higher than 80.4% (45/56) in the acupuncture group and 78.2% (43/55) in the Chinese medication group (P<0.05). Compared before treatment, the GDS scores in the three groups were increased and the TCM symptom scores were reduced after treatment and at 3-month, 6-month and 12-month follow-up visit (P<0.05). The GDS score in the combined group was higher than that in the acupuncture group and the Chinese medication group, and the TCM symptom score was lower than that in the acupuncture group and Chinese medication group (P<0.05). After treatment, the serum levels of IgA, IgG and IgM in the combined group were increased (P<0.05), and the serum levels of MBP, HMGBl and NSE were decreased (P<0.05), and the improvements were superior to those in the acupuncture group and the Chinese medication group (P<0.05). CONCLUSION: Acupuncture combined with Heixiaoyao powder could effectively improve the development quotient in children with cerebral palsy (liver-qi stagnation, spleen-kidney deficiency syndrome), regulate the serum immune indexes and nerve growth related protein levels.


Assuntos
Terapia por Acupuntura , Paralisia Cerebral , Pontos de Acupuntura , Paralisia Cerebral/tratamento farmacológico , Criança , Humanos , Pós , Resultado do Tratamento
3.
Life (Basel) ; 11(3)2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33804020

RESUMO

Chloranthus japonicus has been heavily investigated for the treatment of various diseases. This paper attempts to show that Chloranthus japonicus can modulate adipocyte differentiation of preadipocytes. To establish this, we investigated the effects of Chloranthus japonicus extract in peroxisome proliferator-activated receptor γ (PPARγ) expression, adipogenesis, and the underlying molecular mechanisms in C3H10T1/2 and 3T3-L1 cells. Our data showed that Chloranthus japonicus methanol extract increased lipid accumulation and promoted adipocyte differentiation. Further studies on the fractionation with various solvents led to the identification of Chloranthus japonicus hexane extract (CJHE) as the most potent inducer of adipocyte differentiation. CJHE consistently increased lipid accumulation and adipocyte marker expression including Pparγ and it acted during the early stages of adipocyte differentiation. Mechanistic studies revealed that CJHE and a Wnt inhibitor similarly stimulated adipogenesis and were active in Wnt-selective reporter assays. The effects of CJHE were inhibited by Wnt3a protein treatment and were significantly blunted in ß-catenin-silenced cells, further suggesting that CJHE acted on Wnt pathways to promote adipogenesis. We also showed that Chloranthus japonicus extracts generated from different plant parts similarly promoted adipocyte differentiation. These results identified Chloranthus japonicus as a pro-adipogenic natural product and suggest its potential use in metabolic syndrome.

4.
Biomedicines ; 9(3)2021 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-33805692

RESUMO

Parkinson's disease (PD) is characterized by progressive dopaminergic neuron loss or dysfunction and is the second most prevalent neurodegenerative disorder after Alzheimer's disease. However, current therapeutic strategies for PD are limited to treating the outcomes of this disease rather than preventing it. Sinapic acid (SA) is a phenolic compound with potential antioxidant properties, which reportedly acts as a therapeutic agent against many diseases including cancer, as well as cardiac and liver diseases. However, little is known about the effects of SA against neurodegenerative disorders. Therefore, our study sought to evaluate the neuroprotective effects of non-cytotoxic concentrations of SA against 6-hydroxydopamine (6-OHDA)-induced neurotoxicity in SH-SY5Y human neuroblastoma cells, which we used as an in vitro PD model. SA increased cell viability and rescued the cells from 6-OHDA-induced apoptotic cell death. Additionally, oxidative stress responses were significantly blocked by SA, including reactive oxygen species (ROS) overproduction and decreased expression levels of antioxidant proteins. Notably, SA also attenuated mitochondrial dysfunction and endoplasmic reticulum (ER) stress. Moreover, SA dramatically inhibited the activation of mitogen-activated protein kinase (MAPK) proteins. Taken together, our findings highlight the potential PD prevention effects of SA, as well as its underlying mechanisms, making this compound a promising prevention and treatment agent for PD.

5.
Artigo em Inglês | MEDLINE | ID: mdl-33842953

RESUMO

AIMS: To evaluate the impact of coronary artery calcium (CAC) score, minimal lumen area (MLA), and length of coronary artery stenosis on the diagnostic performance of the machine-learning-based computed tomography-derived fractional flow reserve (ML-FFR). METHODS AND RESULTS: In 471 patients with coronary artery disease, computed tomography angiography (CTA) and invasive coronary angiography were performed with fractional flow reserve (FFR) in 557 lesions at a single centre. Diagnostic performances of ML-FFR, computational fluid dynamics-based CT-FFR (CFD-FFR), MLA, quantitative coronary angiography (QCA), and visual stenosis grading were evaluated using invasive FFR as a reference standard. Diagnostic performances were analysed according to lesion characteristics including the MLA, length of stenosis, CAC score, and stenosis degree. ML-FFR was obtained by automated feature selection and model building from quantitative CTA. A total of 272 lesions showed significant ischaemia, defined by invasive FFR ≤0.80. There was a significant correlation between CFD-FFR and ML-FFR (r = 0.99, P < 0.001). ML-FFR showed moderate sensitivity and specificity in the per-patient analysis. Diagnostic performances of CFD-FFR and ML-FFR did not decline in patients with high CAC scores (CAC > 400). Sensitivities of CFD-FFR and ML-FFR showed a downward trend along with the increase in lesion length and decrease in MLA. The area under the curve (AUC) of ML-FFR (0.73) was higher than those of QCA and visual grading (AUC = 0.65 for both, P < 0.001) and comparable to those of MLA (AUC = 0.71, P = 0.21) and CFD-FFR (AUC = 0.73, P = 0.86). CONCLUSION: ML-FFR showed comparable results to MLA and CFD-FFR for the prediction of lesion-specific ischaemia. Specificities and accuracies of CFD-FFR and ML-FFR decreased with smaller MLA and long lesion length.

6.
Acc Chem Res ; 2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33843190

RESUMO

ConspectusMetal-organic frameworks (MOFs) are a huge, rapidly growing class of crystalline, porous materials that consist of inorganic nodes linked by organic struts. Offering the advantages of thermal stability combined with high densities of accessible reactive sites, some MOFs are good candidate materials for applications in catalysis and separations. Such MOFs include those with nodes that are metal oxide clusters (e.g., Zr6O8, Hf6O8, and Zr12O22) and long rods (e.g., [Al(OH)]n). These nanostructured metal oxides are often compared with bulk metal oxides, but they are in essence different because their structures are not the same and because the MOFs have a high degree of uniformity, offering the prospect of a deep understanding of reactivity that is barely attainable for most bulk metal oxides because of their surface heterogeneity. This prospect is being realized as it has become evident that adventitious components on MOF node surfaces, besides the linkers, are crucial. These ligands arise from modulators, solvents, or products of solvent decomposition in MOF synthesis solutions, and because they are minor components that are often irregularly placed on defects, they may not show up in X-ray diffraction (XRD) crystal structures. Hydroxyl groups on the nodes (like those on bulk metal oxides) are regarded as native functional groups arising from solvent water, but they may barely be present initially, with common ligands instead being formate and acetate formed from modulators formic acid and acetic acid. (Formate also arises from the decomposition of dimethylformamide (DMF) solvent.) Replacement and control of the node ligands is facilitated by postsynthesis reactions (e.g., with alcohols or aqueous HCl/H2SO4 solutions) or as a result of high-temperature decomposition. In catalysis, adventitious node ligands can be (a) reaction inhibitors that block active sites on the nodes (e.g., formate blocking Zr, Hf, or Al Lewis acid sites); (b) reaction intermediates (e.g., ethoxy in ethanol dehydration); or (c) active sites themselves (e.g., terminal OH groups in tert-butyl alcohol (TBA) dehydration). Surprisingly, in view of the catalytic importance of such ligands on bulk metal oxides, their subtle chemistry on MOF nodes is only recently being determined. We describe (1) methods for identifying and quantifying node ligands (especially by IR spectroscopy and by 1H NMR spectroscopy of MOFs digested in NaOH/D2O solutions); (2) node ligand surface chemistry expressed as reaction networks; (3) catalysis, with mechanisms and energetics determined by density functional theory (DFT) and spectroscopy; and (4) MOF unzipping by reactions of linker carboxylate ligands with reactants such as alcohols that break node-linker bonds, a cause of catalyst deactivation and also an indicator of node-linker bond strength and MOF stability.

7.
Nano Lett ; 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33825482

RESUMO

Selective doping in semiconductors is essential not only for monolithic integrated circuity fabrications but also for tailoring their properties including electronic, optical, and catalytic activities. Such active dopants are essentially point defects in the host lattice. In atomically thin two-dimensional (2D) transition-metal dichalcogenides (TMDCs), the roles of such point defects are particularly critical in addition to their large surface-to-volume ratio, because their bond dissociation energy is relatively weaker, compared to elemental semiconductors. In this Mini Review, we review recent advances in the identifications of diverse point defects in 2D TMDC semiconductors, as active dopants, toward the tunable doping processes, along with the doping methods and mechanisms in literature. In particular, we discuss key issues in identifying such dopants both at the atomic scales and the device scales with selective examples. Fundamental understanding of these point defects can hold promise for tunability doping of atomically thin 2D semiconductor platforms.

8.
Sensors (Basel) ; 21(6)2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33799625

RESUMO

Wind action is one of the environmental actions that has significant static and dynamic effects on long-span bridges. The lateral wind speed is the main factor affecting the lateral displacement of the main girder of the bridge. The main objective of the paper is to use the improved multi-rate fusion method to correct the monitoring data so that accurate correlation modeling of wind speed-displacement can be achieved. Two Kalman gain coefficients are introduced to improve the traditional multi-rate fusion method. The fusion method is verified by the results of simulated data analysis in time domain and frequency domain. Then, the improved multi-rate fusion method is used to fuse the monitoring lateral displacement and acceleration data of a bridge under strong wind action. The corrected lateral wind speed and displacement data is further applied to establish the correlation model through the linear regression. The improved multi-rate fusion method can overcome the inaccuracy of the high frequency stage of a Global Positioning System (GPS) sensor and the low frequency stage of acceleration sensor. The correlation coefficient of wind speed-displacement after fusion increases and the confidence interval width of regression model decreases, which indicates that the accuracy of the correlation model between wind speed and displacement is improved.

9.
Pol J Microbiol ; 70(1): 3-11, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33815522

RESUMO

Aspergillus fumigatus is one of the ubiquitous fungi with airborne conidia, which accounts for most aspergillosis cases. In immunocompetent hosts, the inhaled conidia are rapidly eliminated. However, immunocompromised or immunodeficient hosts are particularly vulnerable to most Aspergillus infections and invasive aspergillosis (IA), with mortality from 50% to 95%. Despite the improvement of antifungal drugs over the last few decades, the therapeutic effect for IA patients is still limited and does not provide significant survival benefits. The drawbacks of antifungal drugs such as side effects, antifungal drug resistance, and the high cost of antifungal drugs highlight the importance of finding novel therapeutic and preventive approaches to fight against IA. In this article, we systemically addressed the pathogenic mechanisms, defense mechanisms against A. fumigatus, the immune response, molecular aspects of host evasion, and vaccines' current development against aspergillosis, particularly those based on AFMP4 protein, which might be a promising antigen for the development of anti-A. fumigatus vaccines.

10.
West J Nurs Res ; : 193945921996648, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33666119

RESUMO

Self-management is essential for patients who require regular hemodialysis treatment. This study aimed to explore the relationships between social support, sense of coherence (SOC), and self-management in hemodialysis patients and to examine whether SOC plays a mediating role. In a cross-sectional study, 402 hemodialysis patients from four tertiary hospitals were recruited. Data were analyzed using structural equation modeling. Social support, SOC, and self-management were significantly correlated with each other. The proposed model provided a good fit to the data. Social support had a direct effect on self-management and SOC, partially mediated the effect of social support on self-management (ß = 0.248, p = 0.001). Social support and SOC explained 69% of the variance in self-management. Our findings indicate that health care providers can enhance social support with an emphasis on strengthening SOC strategies to better improve self-management in hemodialysis patients.

11.
Clin Endosc ; 2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33657783

RESUMO

Colonic diffuse ganglioneuromatosis is an extremely rare disease in which multiple tumors derived from the ganglion cells, nerve fibers, and supporting cells are distributed in the colon. It is generally considered to be a benign neoplastic condition and is occasionally associated with rare hereditary conditions such as neurofibromatosis type I or multiple endocrine neoplasia type 2B. Here, we report a case of a patient in whom colon cancer developed 12 years after the initial diagnosis of colonic diffuse ganglioneuromatosis, which suggests a possible association between colonic diffuse ganglioneuromatosis and colorectal cancer.

12.
J Phys Chem A ; 2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33651628

RESUMO

Mass-analyzed threshold ionization (MATI) spectroscopy was used to measure the vibronic spectra of LnO (Ln = La and Ce). Single-reference coupled cluster and relativistic multireference configuration calculations were carried out to compare with the measured vibronic energies. The spectrum of LaO displays a single vibronic band system, while that of CeO shows multiple ones. The ionization energies of LaO and CeO are measured as 5.2446(6) and 5.3332(6) eV, respectively, which are a 100-fold improvement over the literature values. The vibrational energies of the neutral molecule and corresponding ion reveal the charge effect on the metal-oxygen bond of both species. The single band system in the spectrum of LaO arises from the transition of the ground state of the neutral molecule with the La(6s1)O(2p6) valence configuration to the ground state of the singly charged ion with the La(6s0)O(2p6) configuration. The multiple band systems in the spectrum of CeO are attributed to the spin-orbit coupling for the Ce(4f16s1)O(2p6) configuration of the neutral molecule and an excited state for the Ce(4f1)O(2p6) configuration of the ion.

13.
Sci Rep ; 11(1): 6284, 2021 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-33737711

RESUMO

We aimed to investigate the endoscopic features and clinical course of CMV gastroenterocolitis in immunocompetent patients. We reviewed the medical records and endoscopic images of 86 immunocompetent patients with CMV gastroenterocolitis. Immunocompetent patients were defined as those without congenital or acquired immunodeficiency syndrome, use of anti-cancer chemotherapeutic and immunosuppressive agents, and inflammatory bowel diseases. The mean age was 65.5 ± 11.8 years and 53 (61.6%) were male. Sixty-eight (79.1%) patients had comorbidities. Upper gastrointestinal-dominant, small bowel-dominant, and colon-dominant types were observed in 19, 7, and 60 patients, respectively. Endoscopic features could be classified into discrete ulcerative type with/without exudate and diffuse erythematous type with/without exudate. Antiviral treatment with ganciclovir was initiated in 51 patients (59.3%), 40 of whom improved and 1 improved after changing ganciclovir to foscarnet. Thirty-three patients (38.4%) improved without antiviral treatment. Surgery was necessary in two patients because of colon perforation before antiviral treatment. Another two patients underwent surgery because of sigmoid stricture and cecal perforation during antiviral treatment. Endoscopic type was not associated with clinical outcomes, such as surgery and death. CMV gastroenterocolitis in immunocompetent patients mostly occur in older patients with comorbidities, and the endoscopic features vary with no association with clinical outcomes.

14.
Artigo em Inglês | MEDLINE | ID: mdl-33783045

RESUMO

BACKGROUND AND AIM: Data comparing the outcomes of cyclosporin A (CsA) and infliximab (IFX) as rescue therapy for steroid-refractory acute severe ulcerative colitis (SR-ASUC) among Asians are scarce. METHODS: In this single-center study, we retrospectively reviewed 121 patients with SR-ASUC according to the Truelove and Witts' criteria who received CsA or IFX as rescue therapy between 1995 and 2015. The cumulative rates of treatment failure and colectomy at 3 months were compared. Treatment failure was defined as colectomy, switch to other medications, acute flare-up events requiring steroid treatment, and adverse events leading to drug interruption. RESULTS: Among 121 patients with SR-ASUC (male, 55.6%; median disease duration, 47.1 months; extensive colitis, 61.2%), 23 received CsA as the rescue therapy. Baseline characteristics (e.g., age at diagnosis, sex, disease duration, disease extent at rescue therapy, Mayo score at treatment initiation) were comparable between the two groups. During follow-up (median, 45 months; IQR 29.3-61.8), 84 patients (69.4%) experienced treatment failure and 25 patients (20.7%) underwent colectomy. The CsA group and the IFX group did not show significant differences in the cumulative rates of treatment failure (39.1% vs. 34.7%, P=0.714) and colectomy (26.1% vs. 13.3%, P=0.198) at 3 months. Previous use of azathioprine (OR=2.309, 95% CI=1.076-4.951, P=0.032) was associated with treatment failure at 3 months. Mayo score>10 at the time of rescue therapy was significantly associated with colectomy at 3 months (OR=8.444, 95% CI=2.592-27.506, P<0.001). CONCLUSION: Among Korean patients with SR-ASUC, the rates of treatment failure and colectomy at 3 months were not significantly different between the CSA and the IFX treatment groups.

15.
J Colloid Interface Sci ; 593: 125-132, 2021 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-33744523

RESUMO

Self-assembly of colloidal nanoparticles (NPs) into well-defined superstructures has been recognized as one of the most promising ways to fabricate rationally-designed functional materials for a variety of applications. Introducing hierarchical mesoporosity into NP superstructures will facilitate mass transport while simultaneously enhancing the accessibility of constituent NPs, which is of critical importance for widening their applications in catalysis and energy-related fields. Herein, we develop a colloidal co-assembly strategy to construct mesostructured, carbon-coated Co0.5Fe2.5O4 NP superstructures (M-C@CFOSs), which show great promise as highly efficient electrocatalysts for the oxygen evolution reaction (OER). Specifically, organically-stabilized SiO2 NPs are employed as both building blocks and sacrificial template, which co-assemble with Co0.5Fe2.5O4 NPs to afford binary NP superstructures through a solvent drying process. M-C@CFOSs are obtainable after in situ ligand carbonization followed by the selective removal of SiO2 NPs. The hierarchical mesoporous structure of M-C@CFOSs, combined with the conformal graphitic carbon coating derived from the native organic ligands, significantly improves their electrocatalytic performance as OER electrocatalysts when compared with nonporous Co0.5Fe2.5O4 NP superstructures. This work establishes a new and facile approach for designing NP superstructures with hierarchical mesoporosity, which may find wide applications in energy storage and conversion.

17.
J Med Chem ; 64(6): 3381-3391, 2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33688738

RESUMO

Nitroimidazoles are one of the most common radiosensitizers investigated to combat hypoxia-induced resistance to cancer radiotherapy. However, due to poor selectivity distinguishing cancer cells from normal cells, effective doses of radiosensitization are much closer to the doses of toxicity induced by nitroimidazoles, limiting their clinical application. In this work, a tumor-targeting near-infrared (NIR) cyanine dye (IR-808) was utilized as a targeting ligand and an NIR fluorophore tracer to chemically conjugate with different structures of hypoxia-affinic nitroimidazoles. One of the NIR fluorophore-conjugated nitroimidazoles (808-NM2) was identified to preferentially accumulate in hypoxic tumor cells, sensitively outline the tumor contour, and effectively inhibit tumor growth synergistically by chemotherapy and radiotherapy. More importantly, nitroimidazoles were successfully taken into cancer cell mitochondria via 808-NM2 conjugate to exert the synergistic effect of chemoradiotherapy. Regarding the important roles of mitochondria on cancer cell survival and metastasis under hypoxia, 808-NM2 may be hopeful to fight against hypoxic tumors.

18.
J Zhejiang Univ Sci B ; 22(3): 171-189, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33719223

RESUMO

The role of point-of-care (POC) diagnostics is important in public health. With the support of smartphones, POC diagnostic technologies can be greatly improved. This opportunity has arisen from not only the large number and fast spread of cell-phones across the world but also their improved imaging/diagnostic functions. As a tool, the smartphone is regarded as part of a compact, portable, and low-cost system for real-time POC, even in areas with few resources. By combining near-infrared (NIR) imaging, measurement, and spectroscopy techniques, pathogens can be detected with high sensitivity. The whole process is rapid, accurate, and low-cost, and will set the future trend for POC diagnostics. In this review, the development of smartphone-based NIR fluorescent imaging technology was described, and the quality and potential of POC applications were discussed.

19.
Ying Yong Sheng Tai Xue Bao ; 32(3): 951-958, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33754561

RESUMO

To solve the problem of uncoordinated source-sink relationship that limits the increase of peanut yield, we investigated the regulating effects of ethephon on the formation of source-sink in cultivar Shanhua 9 by spraying at 10, 20, and 30 d after anthesis in a field experiment. The results showed that spraying ethephon at 10 d and 20 d after anthesis significantly reduced the number of flowers, pegs and young pods, but increased the number of immature pods and mature pods. Spraying at 30 d after anthesis did not affect the number of flowers, pegs and young pods. Spraying ethephon could improve the leaf area per plant. Spraying at 10 d after anthesis achieved the highest leaf area per plant and the increment amplitude decreased with the delay of spraying stage. Spraying ethephon at 10 d and 20 d after anthesis significantly improved the photosynthetic performance of peanut, whereas spraying at 30 days after anthesis increased the photosynthesis only in the short-term and had no effect at late growth period. In terms of the comprehensive characters of source and sink, spraying ethephon at 20 d after anthesis achieved the most harmonious source-sink relationship, which could promote the transport of photosynthate to pods and increase the economic pods ratio, pod fullness, and the yield. Therefore, spraying ethephon is an effective practice to solve the problems of "more flowers but less pegs" and "more pods but less kernels" in peanut. The optimum spraying stage of ethephon to regulate flowering should be at 20 d after anthesis.


Assuntos
Arachis , Fotossíntese , Compostos Organofosforados/farmacologia , Folhas de Planta
20.
Huan Jing Ke Xue ; 42(4): 1939-1945, 2021 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-33742829

RESUMO

In order to study the effects of chlorine dioxide (ClO2) disinfection on the super antibiotic resistance genes (SARGs), the final effluents before and after chlorine dioxide were sampled throughout one year in a wastewater treatment plant (WWTP). The bacteria and extracellular nucleic acid were collected using microporous membrane filtration and nucleic acid adsorption particles, respectively. A total of 9 SARGs was detected through a quantitative real-time polymerase chain reaction (qPCR). The results revealed that both intracellular and extracellular NDM-1, MCR-1, and MEC-A could be positively detected in the samples. Overall, ClO2 disinfection enhanced the relative abundance of the iSARGs (P<0.05), exhibiting a seasonal pattern, and increasing in the spring, summer, and autumn. In spring, it improved the most, up to twice the abundance. No SARGs were detected positive in the winter, either intracellularly or extracellularly. There was no significant variation in the concentrations of eSARGs before and after ClO2 disinfection. Therefore, ClO2 disinfection cannot effectively remove iSARGs and eSARGs in the final effluent from the WWTP.


Assuntos
Compostos Clorados , Desinfetantes , Purificação da Água , Antibacterianos/farmacologia , Cloro , Compostos Clorados/farmacologia , Desinfetantes/farmacologia , Desinfecção , Resistência Microbiana a Medicamentos/genética , Óxidos/farmacologia
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