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1.
Carbohydr Polym ; 300: 120264, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36372515

RESUMO

After bone tumor resection, the severe complications including cancer recurrence, infection and extensive bone loss are still a challenge. To address this problem, a chitosan/hydroxypropyltrimethyl ammonium chloride chitosan/hydroxyapatite/black phosphorus (CS/HC/HA/BP) hybrid photothermal scaffold with a multistage photothermal strategy was developed. HC-stabilized BP endowed the scaffold with simultaneous antitumor/antibacterial properties under photothermal stimulation of <50 °C. Subsequently, excellent osteogenesis could be achieved with mild hyperthermia stimulation (∼42 °C) through up-regulating the expressions of heat shock proteins. Under NIR irradiation, the scaffold could eliminate 95 % of osteosarcoma cells as well as 97 % of E. coli and 92 % of S. aureus. The osteogenic gene expressions of ALP, COL 1A1, and OCN in photothermal group were 1.64, 1.31 and 1.27 folds higher than that of non-photothermal group in vivo, respectively. Therefore, the obtained scaffold synergized with multistage photothermal strategy was effective and a reference for the treatment of other complex diseases.


Assuntos
Neoplasias Ósseas , Quitosana , Humanos , Quitosana/uso terapêutico , Tecidos Suporte , Staphylococcus aureus , Escherichia coli , Osteogênese , Neoplasias Ósseas/terapia
2.
Microbiol Spectr ; : e0287122, 2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36350141

RESUMO

Marek's disease virus (MDV) induces immunosuppression and neoplastic disease in chickens. The virus is controllable via an attenuated meq deletion mutant virus, which has the disadvantage of retaining the ability to induce lymphoid organ atrophy. To overcome this deficiency and produce more vaccine candidates, a recombinant MDV was generated from the highly virulent Md5BAC strain, in which both meq and a cytolytic replication-related gene, pp38, were deleted. Replication of the double deletion virus, Md5BAC ΔmeqΔpp38, was comparable with that of the parental virus in vitro. The double deletion virus was shown to be fully attenuated and to reduce lymphoid organ atrophy in vivo. Crucially, Md5BAC ΔmeqΔpp38 confers superior protection against highly virulent virus compared with a commercial vaccine strain, CVI988/Rispens. Transcriptomic profiling indicated that Md5BAC ΔmeqΔpp38 induced a different host immune response from CVI988/Rispens. In summary, a novel, effective, and safe vaccine candidate for prevention and control of MD caused by highly virulent MDV is reported. IMPORTANCE MDV is a highly contagious immunosuppressive and neoplastic pathogen. The virus can be controlled through vaccination via an attenuated meq deletion mutant virus that retains the ability to induce lymphoid organ atrophy. In this study, we overcame the deficiency by generating meq and pp38 double deletion mutant virus. Indeed, the successfully generated meq and pp38 double deletion mutant virus had significantly reduced replication capacity in vivo but not in vitro. It was fully attenuated and conferred superior protection efficacy against very virulent MDV challenge. In addition, the possible immunological protective mechanism of the double deletion mutant virus was shown to be different from that of the gold standard MDV vaccine, CVI988/Rispens. Overall, we successfully generated an attenuated meq deletion mutant virus and widened the range of potential vaccine candidates. Importantly, this study provides for the first time the theoretical basis of vaccination induced by fully attenuated gene-deletion mutant virus.

3.
J Anim Sci Biotechnol ; 13(1): 120, 2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36336695

RESUMO

BACKGROUND: In rodents, research has revealed a role of liver X receptors (LXR) in controlling lipid homeostasis and regulating the synthesis of polyunsaturated fatty acids (PUFA). Recent data suggest that LXRB is the predominant LXR subtype in ruminant mammary cells, but its role in lipid metabolism is unknown. It was hypothesized that LXRB plays a role in lipid homeostasis via altering the synthesis of PUFA in the ruminant mammary gland. We used overexpression and knockdown of LXRB in goat primary mammary epithelial cells (GMEC) to evaluate abundance of lipogenic enzymes, fatty acid profiles, content of lipid stores and activity of the stearoyl-CoA desaturase (SCD1) promoter. RESULTS: Overexpression of LXRB markedly upregulated the protein abundance of LXRB while incubation with siRNA targeting LXRB markedly decreased abundance of LXRB protein. Overexpression of LXRB plus T0901317 (T09, a ligand for LXR) dramatically upregulated SCD1 and elongation of very long chain fatty acid-like fatty acid elongases 5-7 (ELOVL 5-7), which are related to PUFA synthesis. Compared with the control, cells overexpressing LXRB and stimulated with T09 had greater concentrations of C16:0, 16:1, 18:1n7,18:1n9 and C18:2 as well as desaturation and elongation indices of C16:0. Furthermore, LXRB-overexpressing cells incubated with T09 had greater levels of triacylglycerol and cholesterol. Knockdown of LXRB in cells incubated with T09 led to downregulation of genes encoding elongases and desaturases. Knockdown of LXRB attenuated the increase in triacylglycerol and cholesterol that was induced by T09. In cells treated with dimethylsulfoxide, knockdown of LXRB increased the concentration of C16:0 at the expense of C18:0, while a significant decrease in C18:2 was observed in cells incubated with both siLXRB and T09. The abundance of sterol regulatory element binding transcription factor 1 precursor (pSREBP1) and its mature fragment (nSREBP1) was upregulated by T09, but not LXRB overexpression. In the cells cultured with T09, knockdown of LXRB downregulated the abundance for pSREBP1 and nSREBP1. Luciferase reporter assays revealed that the activities of wild type SCD1 promoter or fragment with SREBP1 response element (SRE) mutation were decreased markedly when LXRB was knocked down. Activity of the SCD1 promoter that was induced by T09 was blocked when the SRE mutation was introduced. CONCLUSION: The current study provides evidence of a physiological link between the LXRB and SREBP1 in the ruminant mammary cell. An important role was revealed for the LXRB-SREBP1 network in the synthesis of PUFA via the regulation of genes encoding elongases and desaturases. Thus, targeting this network might elicit broad effects on lipid homeostasis in ruminant mammary gland.

4.
Mater Today Bio ; 17: 100474, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36425924

RESUMO

The application of circulating tumor cells (CTCs) in both clinical practice and research has been continuously limited by the rare number of targets that can be found in a tube of peripheral blood. Diagnostic leukapheresis (DLA) was used to increase the sampling volume. AdnaTest was used to process the whole leukopak, and the RNAs of captured CTCs was then profiled by NanoString nCounter platform. Spike-in experiments and leukopaks from patients with metastatic prostate cancer were used to validate this new strategy. The whole leukopak was further concentrated five times to reduce the total volume from 150 â€‹mL to 30 â€‹mL, which enabled it to be processed by 3 separate AdnaTest kits. The spike-in experiment demonstrated a reliable capture when there were more than 100 cancer cells/10 â€‹mL of concentrated leukopak. In 1 out of 5 real patient samples, CTCs were only detected in the leukopak, but not in peripheral blood. The RNA profiling of DLA CTCs indicated a more aggressive phenotype of CTCs occurred when the patient was experiencing a disease relapse, even when the serum prostate specific antigen (PSA) level was still relatively low and CTCs in peripheral blood were not detectable. We established a new protocol, integrating DLA, AdnaTest and NanoString nCounter technology, to profile RNAs from CTCs captured from a large blood screening volume. The new protocol can process the whole leukopak with sensitive CTC capture. The RNA profiling of CTCs can provide valuable information for disease monitoring.

5.
Front Neurol ; 13: 992396, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36353136

RESUMO

Objective: The aim of this study was to evaluate the effectiveness and safety of rescue therapy, a therapy in which rescue devices such as balloon angioplasty, Apollo stent, Wingspan stent, Solitaire stent, or other self-expanding stents are used after the failure of mechanical thrombectomy (MT) and to determine the most effective rescue measure for acute basilar artery occlusion (BAO) after the failure of MT. Methods: For this study, we recruited patients from the BASILAR registry. All participants were divided into three groups: the recanalized with rescue therapy group, the recanalized without rescue therapy group, and the non-recanalized group. Clinical outcomes at 90 days and 1 year were compared. The association of rescue measures with favorable outcomes (modified Rankin Scale [mRS] score of 0-3) in patients achieving successful recanalization via rescue therapy was estimated using multivariate logistic regression analyses. Results: Among the participants, recanalization failure was found in 112 patients and successful recanalization in 473 patients, with 218 patients receiving rescue therapy and 255 patients without rescue therapy. Of these, 111 (43.5%) patients in the recanalized without rescue therapy group, 65 (29.8%) patients in the recanalized with rescue therapy group, and nine (8.0%) patients in the non-recanalized group achieved favorable outcomes at 90 days. Both the recanalization with rescue therapy and the recanalization without rescue therapy groups were associated with favorable outcomes at 90 days and 1 year compared with the non-recanalized group. Moreover, in patients receiving rescue therapy, Wingspan stents, Apollo stents, and balloon angioplasty were associated with higher rates of favorable outcomes at 90 days and 1 year than Solitaire stents. Conclusion: Whether rescue therapy is administered or not, recanalization leads to favorable outcomes in patients with acute BAO. For acute BAO after MT failure, balloon angioplasty, Wingspan stenting, and Apollo stenting could be considered effective and safe rescue options but not Solitaire stenting.

6.
ISA Trans ; 2022 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-36357219

RESUMO

To well extract the early fault characteristics of rotating machines, a new fast sparsity-enabled feature-energy-ratio method is investigated in this paper. This method includes two stages. In the first stage, the spectrum is adaptively segmented through a coarse-to-fine strategy based on the ordered local maximums. Thus, the fault characteristic band can be divided automatically. A novel index based on sparsity, energy ratio, and kurtosis, is constructed to evaluate periodic impulses in each sub-signal, and it can evaluate the periodic impulses from the globality and locality. In the second stage, the Fourier spectrum from the first stage are refined by an improved sparse coding shrinkage denoising (SCSD) method whose parameters can be dynamically determined for each point. Within the improved SCSD approach, the differential result of the amplitude spectrum is used as input to improve the sparsity. Moreover, the ratios between the SCSD output and its input are applied to weigh the Fourier spectrum and maintain the phase information. Finally, the inverse fast Fourier transform and squared envelope spectra are applied to detect the fault characteristics. Bearing and gearbox vibration signals are used to validate the proposed methodology. The experimental results show that the proposed method is superior to some typical methods and the proposed index are robust to the interferences from aperiodic impulses. Therefore, the proposed method has great potential in the fault diagnosis of rotating machine.

7.
Front Public Health ; 10: 1018724, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36388309

RESUMO

Background: Female sex workers (FSWs) are considered highly vulnerable to sexually transmitted infections (STIs), but available data on the prevalence of STIs among FSWs in China is limited at a provincial level. This study aimed to evaluate the prevalence of STIs and risk factors among FSWs in Jiangsu, China. Methods: We conducted a multicenter cross-sectional study in seven cities of Jiangsu to investigate the prevalence and risk factors associated with HIV and other STIs. Blood and urine were collected to test for HIV, syphilis, Hepatitis C (HCV), Neisseria gonorrhoeae (NG) and Chlamydia trachomatis (CT) infections. Results: We enrolled 3,580 FSWs. The overall prevalence of bacterial STIs was 6.2% (5.4%-7.0%). The prevalence of HIV, syphilis infection, HCV, NG and CT were 0.1% (95%CI, 0.0-0.2), 1.8% (95%CI, 1.4-2.3), 0.3% (95%CI, 0.1-0.5), 0.3% (95%CI, 0.2-0.5) and 4.3% (95%CI, 3.6-5.0), respectively. Most FSWs (85.6%) reported consistent condom use with clients in the past month. Only 10.6% of FSWs reported group sex, and 68.3% self-reported HIV testing in the previous year. According to the multivariable model, having group sex in the past year (aOR, 2.521, 95%CI: 1.366-4.651) and HIV infection (aOR, 26.260, 95%CI: 2.432-283.563) were associated with a higher risk of syphilis infection. Migrants (aOR, 1.669, 95%CI: 1.163-2.395), having a history of STIs in the past year (aOR, 4.601, 95%CI: 1.003-21.118), and NG infection (aOR, 38.549, 95%CI: 11.214-132.514) were associated with a higher risk of CT infection. On the contrary, FSWs aged older than 25 were associated with lower risk of syphilis infection (25-34: aOR, 0.339, 95%CI: 0.151-0.763) and CT infection (25-34: aOR, 0.503, 95%CI: 0.316-0.802; ≥35: aOR, 0.578, 95%CI: 0.362-0.925). Conclusion: This study's prevalence rates of syphilis and CT infections show the need to promote comprehensive STIs control and prevention strategies, including behavioral intervention and STIs screening, especially in younger high-risk populations. With the increasing coverage of HIV testing, integrating other STIs screening with HIV testing may be a reasonable way to implement comprehensive STIs control and prevention.


Assuntos
Infecções por HIV , Hepatite C , Profissionais do Sexo , Infecções Sexualmente Transmissíveis , Sífilis , Feminino , Humanos , Idoso , Sífilis/epidemiologia , Estudos Transversais , Chlamydia trachomatis , Infecções por HIV/epidemiologia , Prevalência , Infecções Sexualmente Transmissíveis/epidemiologia , Hepatite C/epidemiologia , China/epidemiologia
8.
Cancer Res ; 2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36413141

RESUMO

Abiraterone is a standard treatment for metastatic castrate-resistant prostate cancer (mCRPC) that slows disease progression by abrogating androgen synthesis and antagonizing the androgen receptor (AR). Here we report that inhibitors of the mitotic regulator polo-like kinase-1 (Plk1), including the clinically active third-generation Plk1 inhibitor onvansertib, synergizes with abiraterone in vitro and in vivo to kill a subset of cancer cells from a wide variety of tumor types in an androgen-independent manner. Gene expression analysis identified an AR-independent synergy-specific gene set signature upregulated upon abiraterone treatment that is dominated by pathways related to mitosis and the mitotic spindle. Abiraterone treatment alone caused defects in mitotic spindle orientation, failure of complete chromosome condensation, and improper cell division independently of its effects on AR signaling. These effects, while mild following abiraterone monotherapy, resulted in profound sensitization to the anti-mitotic effects of Plk1 inhibition, leading to spindle assembly checkpoint-dependent mitotic cancer cell death and entosis. In a murine patient-derived xenograft model of abiraterone-resistant metastatic castration resistant prostate cancer (mCRPC), combined onvansertib and abiraterone resulted in enhanced mitotic arrest and dramatic inhibition of tumor cell growth compared to either agent alone. Overall, this work establishes a mechanistic basis for the phase 2 clinical trial (NCT03414034) testing combined onvansertib and abiraterone in mCRPC patients and indicates this combination may have broad utility for cancer treatment.

9.
Anal Bioanal Chem ; 2022 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-36370201

RESUMO

Cardiomyocyte-derived extracellular vesicles (EVs) are a promising class of biomarkers that can advance the diagnosis of many kinds of cardiovascular diseases. Herein, we develop a new electrochemical method for the feasible detection of cardiomyocyte-derived EVs in biological fluids. The core design of the method is the fabrication of a peptide-anchored biomimetic interface consisting of a lipid bilayer and peptide probes. On the one hand, the lipid bilayer provides excellent antifouling ability to the electrode interface and facilitates the anchoring of peptide probes. On the other hand, the peptide probes equip the electrode interface with excellent binding capability and affinity to CD172a, a specific marker of cardiomyocyte-derived EVs, thus enabling the efficient and selective detection of target EVs. Taking EVs derived from the heart myoblast cells H9C2 as the model target, the method displays a wide linear detection range from 1 × 103 to 1 × 108 particles/mL with a desirable detection limit of 132 particles/mL. Furthermore, the method shows good performance in biological fluids such as serum, and thus may have great potential for practical use in the diagnosis of cardiovascular diseases.

10.
Artigo em Inglês | MEDLINE | ID: mdl-36399156

RESUMO

Bioadhesives with immediate wound closure, efficient hemostasis, and antibacterial properties that can well integrate with tissue are urgently needed in wound management. Natural small biological molecule based bioadhesives hold great promise for manipulating wound healing by taking advantage of integrated functionalities, synthetic simplification, and accuracy, cost efficiency and biosafety. Herein, a natural small biological molecule based bioadhesive, composed of natural small biological molecules (α-lipoic acid and tannic acid) and a small amount of ferric chloride, was prepared via an extremely simple and green route for wound management. In this system, covalent and noncovalent interactions between each component resulted in the self-healing supramolecular bioadhesive. It possessed appropriate wet-tissue adhesion, efficient nonpressing hemostasis and free radical scavenging abilities. More importantly, the interaction between tannic acid and Fe3+ endowed the bioadhesive with innate and steady photothermal activity, which showed excellent photothermal bactericidal activity to both E. coli and S. aureus. The bioadhesive promoted wound healing for linear and circular wounds in vivo, especially for infectious wounds under near-infrared (NIR) irradiation. This bioadhesive will have promising value as a safe and effective antimicrobial adhesive for infectious wound management.

11.
Chemosphere ; 312(Pt 1): 137145, 2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36343739

RESUMO

The rapid recombination of photogenerated electrons and holes, low utilization of visible light and weak oxidation capacity significantly limit the photocatalytic activity for the degradation of organic pollutants. Doping is used as a conventional strategy for regulating the electronic structure of photocatalysts to obtain a wider light absorption, but also suffers from the problems of reduced charge mobility and oxidation capacity, which is not conducive to photocatalytic degradation of pollutants. To address this issue, a nitrogen self-doped hollow nanotubes g-C3N4 (N-PCN) was synthesized by synergistic self-doping and quantum confinement effects. The N-PCN exhibits excellent efficiency in photocatalytic degradation of TC compared to the pristine g-C3N4. The synthesized N-PCN has a more positive conduction band minimum and can generate more photogenerated electrons to reduce oxygen to superoxide radicals. In addition, experimental and theoretical evidence shows that N-self-doping not only suppresses the recombination of photogenerated charge carriers but also facilitates the adsorption of oxygen molecules. Consequently, more superoxide radicals and singlet oxygen are generated through oxygen activation process.

12.
Lancet ; 400(10366): 1847-1857, 2022 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-36351459

RESUMO

BACKGROUND: Previous randomised trials of bivalirudin versus heparin in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI) have reported conflicting results, in part because of treatment with different pharmacological regimens. We designed a large-scale trial examining bivalirudin with a post-PCI high-dose infusion compared with heparin alone, the regimens that previous studies have shown to have the best balance of safety and efficacy. METHODS: BRIGHT-4 was an investigator-initiated, open-label, randomised controlled trial conducted at 87 clinical centres in 63 cities in China. Patients with STEMI undergoing primary PCI with radial artery access within 48 h of symptom onset who had not received previous fibrinolytic therapy, anticoagulants, or glycoprotein IIb/IIIa inhibitors were randomly assigned (1:1) to receive bivalirudin with a post-PCI high-dose infusion for 2-4 h or unfractionated heparin monotherapy. There was no masking. Glycoprotein IIb/IIIa inhibitor use was reserved for procedural thrombotic complications in both groups. The primary endpoint was a composite of all-cause mortality or Bleeding Academic Research Consortium (BARC) types 3-5 bleeding at 30 days. This trial is registered with ClinicalTrials.gov (NCT03822975), and is ongoing. FINDINGS: Between Feb 14, 2019, and April 7, 2022, a total of 6016 patients with STEMI undergoing primary PCI were randomly assigned to receive either bivalirudin plus a high-dose infusion after PCI (n=3009) or unfractionated heparin monotherapy (n=3007). Radial artery access was used in 5593 (93·1%) of 6008 patients. Compared with heparin monotherapy, bivalirudin reduced the 30-day rate of the primary endpoint (132 events [4·39%] in the heparin group vs 92 events [3·06%] in the bivalirudin group; difference, 1·33%, 95% CI 0·38-2·29%; hazard ratio [HR] 0·69, 95% CI 0·53-0·91; p=0·0070). All-cause mortality within 30 days occurred in 118 (3·92%) heparin-assigned patients and in 89 (2·96%) bivalirudin-assigned patients (HR 0·75; 95% CI 0·57-0·99; p=0·0420), and BARC types 3-5 bleeding occurred in 24 (0·80%) heparin-assigned patients and five (0·17%) bivalirudin-assigned patients (HR 0·21; 95% CI 0·08-0·54; p=0·0014). There were no significant differences in the 30-day rates of reinfarction, stroke, or ischaemia-driven target vessel revascularisation between the groups. Within 30 days, stent thrombosis occurred in 11 (0·37%) of bivalirudin-assigned patients and 33 (1·10%) of heparin-assigned patients (p=0·0015). INTERPRETATION: In patients with STEMI undergoing primary PCI predominantly with radial artery access, anticoagulation with bivalirudin plus a post-PCI high-dose infusion for 2-4 h significantly reduced the 30-day composite rate of all-cause mortality or BARC types 3-5 major bleeding compared with heparin monotherapy. FUNDING: Chinese Society of Cardiology Foundation (CSCF2019A01), and a research grant from Jiangsu Hengrui Pharmaceuticals.


Assuntos
Infarto do Miocárdio , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Trombose , Humanos , Heparina/efeitos adversos , Intervenção Coronária Percutânea/efeitos adversos , Infarto do Miocárdio com Supradesnível do Segmento ST/tratamento farmacológico , Quimioterapia Combinada , Complexo Glicoproteico GPIIb-IIIa de Plaquetas , Hemorragia/tratamento farmacológico , Trombose/etiologia
13.
Pharmaceutics ; 14(11)2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36365098

RESUMO

Conventional photothermal therapy (PTT) irradiates the tumor tissues by elevating the temperature above 48 °C to exert thermal ablation, killing tumor cells. However, thermal ablation during PTT harmfully damages the surrounding normal tissues, post-treatment inflammatory responses, rapid metastasis due to the short-term mass release of tumor-cellular contents, or other side effects. To circumvent this limitation, mild-temperature photothermal therapy (MTPTT) was introduced to replace PTT as it exerts its activity at a therapeutic temperature of 42-45 °C. However, the significantly low therapeutic effect comes due to the thermoresistance of cancer cells as MTPTT figures out some of the side-effects issues. Herein, our current review suggested the mechanism and various strategies for improving the efficacy of MTPTT. Especially, heat shock proteins (HSPs) are molecular chaperones overexpressed in tumor cells and implicated in several cellular heat shock responses. Therefore, we introduced some methods to inhibit activity, reduce expression levels, and hinder the function of HSPs during MTPTT treatment. Moreover, other strategies also were emphasized, including nucleus damage, energy inhibition, and autophagy mediation. In addition, some therapies, like radiotherapy, chemotherapy, photodynamic therapy, and immunotherapy, exhibited a significant synergistic effect to assist MTPTT. Our current review provides a basis for further studies and a new approach for the clinical application of MTPTT.

14.
Artigo em Inglês | MEDLINE | ID: mdl-36429949

RESUMO

Rill erosion is one of the major environmental problems in the world; it is an important factor with regard to land degradation and has a serious impact on production and daily life in the region. The widely distributed Yuanmou group stratum promotes the development of rill erosion, whereby the strong time-concentrated rainfall and the alternating arid-humid climate prepare the ground for the development of rills in soils. Therefore, a study of the processes of slope rill erosion was carried out, and a gravel-soil slope in the Yuanmou dry-hot valley was chosen to simulate short-term heavy rainfall (25 mm/h) (No. 1 plot) and moderate rainfall (15 mm/h) (No. 2 plot), to study the erosion processes of soil and the dynamic characteristics of runoff involved in erosion. The study results showed that the width of runoff was significantly different between the two plots, while the depth of runoff was not significantly different. During the rill formation process, the width of the two plots first decreased and then increased with increasing washout duration, while its depth did not change significantly. Flow was the key factor in determining the hydraulic characteristics of runoff, and it had a significant or extremely significant positive correlation with hydraulic characteristics parameters, except in the case of Fr (Froude number) (r = 0.039). The total sediment content (CS) of plot No. 1 (0.158 g/cm3) was significantly different from that of plot No. 2 (0.153 g/cm3), and both CSs in the two plots decreased with increasing washout duration. The CS had an extremely significant negative correlation with τ (runoff shear force) (r = -0.863 **) and DW-f (Darcy-Weisbach drag coefficient) (r = -0.863 **) and a significant negative correlation with Re (Reynolds number) (r = -0.735 *) in the short-term heavy rainfall experiment, while the CS had a significant positive correlation with V (velocity) (r = 0.814 *), R (hydraulic radius) (r = 0.811 *) and P (unit stream power) (r = 0.811 *) in the moderate rainfall experiment. The results of this study will help guide further examination of the processes involved in the dynamic mechanisms of rill erosion on slopes under short-term heavy rainfall conditions.


Assuntos
Chuva , Movimentos da Água , Sedimentos Geológicos , Solo , Rios
15.
Water Res ; 227: 119324, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36368084

RESUMO

In this study, a novel and efficient heterogeneous electro-Fenton (EF) process with a potassium ferrate (K2FeO4) modified carbon felt (Fe-CF) cathode was developed for chloramphenicol (CAP) removal. The catalytic activity was assessed by the comparison of different systems and the effects of multiple operating parameters (K2FeO4 dosage, initial solution pH, applied current) and co-existing constituents. Results indicated that the Fe-CF cathode exhibited excellent performance for CAP degradation (almost 100% removal efficiency within 60 min) over a wide range of pH (pH 3-9) during heterogeneous EF ascribed to the synergistic effect of embedded iron species and porous graphitic carbon structure and effective utilization of the in-situ generated H2O2. Moreover, the Fe-CF cathode possessed good recyclability with low metal leaching (98.2% CAP removal efficiency after reused for 5 times) and outstanding real water application performance. The ∙OH and O2∙- were responsible for CAP degradation, while ∙OH played a main role. Moreover, the toxicity evaluation by E. coli growth experiments demonstrated an efficient toxicity reduction in this system. Overall, a novel heterogeneous EF functional cathode with superior performance was fabricated via a green, low-cost one-step method, which shows promising application potential for actual wastewater treatment.


Assuntos
Peróxido de Hidrogênio , Poluentes Químicos da Água , Fibra de Carbono , Peróxido de Hidrogênio/química , Carbono , Cloranfenicol , Escherichia coli , Poluentes Químicos da Água/química , Oxirredução , Ferro/química , Eletrodos
16.
Chin J Nat Med ; 20(11): 846-853, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36427918

RESUMO

Steroid saponins are secondary metabolites with multiple medicinal values that are found in large quantities in natural medicines, especially Vernonia amygdalina, a famous nature medicine for the treatment of tonsillitis, diabetes, pneumonia. The current study was designed to combine molecular networking (MN) with diagnostic ions for rapid identification of Δ7,9(11) stigmastane-type saponins which were the α-glucosidase inhibitory active substances in V. amygdalina. First, the α-glucosidase inhibitory activities of five Δ7,9(11) stigmastane-type steroid saponins that were previously isolated were screened, which indicated that the Δ7,9(11) stigmastane-type steroid saponin was one of the active constituents responsible for ameliorating diabetes. Furthermore, a strategy was proposed to identify stigmastane-type steroid saponins and verify the plausibility of derived fragmentation pathways by applying MN, MolNetEnhancer and unsupervised substructure annotation (MS2LDA). Based on this strategy, other seven Δ7,9(11) stigmastane-type steroid saponins were identified from this plant. Our research provide scientific evidence for the antidiabetic potential of the steroid saponin-rich extract of V. amygdalina leaf.


Assuntos
Diabetes Mellitus , Saponinas , Vernonia , alfa-Glucosidases/metabolismo , Vernonia/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Folhas de Planta/química , Saponinas/química , Esteroides/química
17.
Front Pharmacol ; 13: 992457, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36330099

RESUMO

Drug-induced pulmonary arterial hypertension (PAH) has been widely reported but PAH caused by leflunomide is very rare. Here we report the case of a young man with nephrotic syndrome treated with leflunomide for 5 years before being admitted to our hospital for dyspnea. After discontinuing leflunomide treatment for 4 months, both the dyspnea and pulmonary artery systolic pressure improved. Right heart catheterization showed in a significant decrease in pulmonary vascular resistance and pulmonary artery pressure 4 months later. Because persistent PAH can lead to right heart failure and even death, identifying and excluding the risk factors is critical; discontinuing leflunomide until a definite cause is identified is highly recommended.

18.
J Med Virol ; 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36401345

RESUMO

Dynamic alteration of the epitranscriptome exerts regulatory effects on the lifecycle of oncogenic viruses in vitro. However, little is known about these effects in vivo because of the general lack of suitable animal infection models of these viruses. Using a model of rapid-onset Marek's disease lymphoma in chickens, we investigated changes in viral and host mRNA N6-methyladenosine (m6 A) modification during Marek's disease virus (MDV) infection in vivo. We found that the expression of major epitranscriptomic proteins varies among viral infection phases, reprogramming both the viral and the host epitranscriptomes. Specifically, the METTL3/14 complex was suppressed during the lytic and reactivation phases of the MDV lifecycle, whereas its expression was increased during the latent phase and in MDV-induced tumors. METTL3/14 overexpression inhibits, whereas METTL3/14 knockdown enhances, MDV gene expression and replication. These findings reveal the dynamic features of the mRNA m6 A modification program during viral replication in vivo, especially in relation to key pathways involved in tumorigenesis. This article is protected by copyright. All rights reserved.

19.
Molecules ; 27(22)2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36432179

RESUMO

Halogen bonds play an important role in many fields, such as biological systems, drug design and crystal engineering. In this work, the structural characteristics of the halogen bond between heteronuclear halogen XD (ClF, BrCl, IBr, ICl, BrF and IF) and benzene were studied using density functional theory. The structures of the complexes between heteronuclear halogen and benzene have Cs symmetry. The interaction energies of the complexes between heteronuclear halogen XD (ClF, BrCl, IBr, ICl, BrF and IF) and benzene range from -27.80 to -37.18 kJ/mol, increasing with the increases in the polarity between the atoms of X and D, and are proportional to the angles of a between the Z axis and the covalent bond of heteronuclear halogen. The electron density (ρ) and corresponding Laplacian (∇2ρ) values indicate that the interaction of the heteronuclear halogen and benzene is a typical long-range weak interaction similar to a hydrogen bond. Independent gradient model analysis suggests that the van der Waals is the main interaction between the complexes of heteronuclear halogen and benzene. Symmetry-adapted perturbation theory analysis suggests that the electrostatic interaction is the dominant part in the complexes of C6H6⋯ClF, C6H6⋯ICl, C6H6⋯BrF and C6H6⋯IF, and the dispersion interaction is the main part in the complexes of C6H6⋯BrCl, C6H6⋯IBr.


Assuntos
Benzeno , Halogênios , Halogênios/química , Ligação de Hidrogênio , Eletricidade Estática , Modelos Moleculares
20.
Org Biomol Chem ; 20(46): 9222-9227, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36377705

RESUMO

Three novel lindenane-monoterpene heterodimers with different skeleton types (1-3), together with a known analogue (4), were obtained from the seeds of Sarcandra glabra. Their structures were elucidated on the basis of comprehensive spectroscopic analyses, single crystal X-ray diffraction, and calculations of ECD. Sarcaglarone A (1) displayed an unprecedented monocyclic monoterpene moiety formed by a free-radical-mediated C1'-C5' bond formation reaction. 6α-Hydroxysarglaperoxide A (2) and 7'-oxyisosarcaglabrin A (3) are C23 and C25 terpenes formed by [2 + 2 + 2] cycloaddition and the Diels-Alder reaction, respectively. Their inhibitory activities against nitric oxide (NO) production were evaluated.

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