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1.
Food Chem ; 372: 131143, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34601419

RESUMO

The frying process is an excellent way to obtain food with desirable sensory. However, some harmful substances, such as aldehydes and monoepoxy oleic acids, could also be produced. This study mainly explores the inhibition of polyphenols from the Camellia oleifera seed cake extract (CSCE) on the formation of polar compounds, core aldehydes, and monoepoxy oleic acids during deep-fat frying. The results showed that the CSCE could significantly decrease peroxide, p-anisidine, total polar, and monoepoxy oleic acids compared with other groups. In addition, the CSCE could significantly inhibit the generation of oxidized triacylglycerol polymer (TGP) and oxidized triacylglycerol (ox-TG), indicating its anti-polymerization activity. The total amount of core aldehydes and glycerol ester core aldehydes (9-oxo) in soybean oil was significantly reduced. Furthermore, CSCE had a better inhibitory effect on monoepoxy fatty acids than TBHQ. Our results might be helpful to provide a basis for the search for new natural antioxidants.


Assuntos
Camellia , Aldeídos , Temperatura Alta , Ácidos Oleicos , Extratos Vegetais , Óleos Vegetais , Sementes
2.
Eur J Med Chem ; 227: 113973, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34752955

RESUMO

On the basis of our previous work, a novel series of (4-(1,2,4-oxadiazol-5-yl)phenyl)-2-aminoacetamide derivatives were synthesized and evaluated as multifunctional ligands for the treatment of Alzheimer's disease (AD). Biological evaluations indicated that the derivatives can be used as anti-AD drugs that have multifunctional properties, inhibit the activity of butyrylcholinesterase (BuChE), inhibit neuroinflammation, have neuroprotective properties, and inhibit the self-aggregation of Aß. Compound f9 showed good potency in BuChE inhibition (IC50: 1.28 ± 0.18 µM), anti-neuroinflammatory potency (NO, IL-1ß, TNF-α; IC50: 0.67 ± 0.14, 1.61 ± 0.21, 4.15 ± 0.44 µM, respectively), and inhibited of Aß self-aggregation (51.91 ± 3.90%). Preliminary anti-inflammatory mechanism studies indicated that the representative compound f9 blocked the activation of the NF-κB signaling pathway. Moreover, f9 exhibited 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radical scavenging effect, and an inhibitory effect on the production of intracellular reactive oxygen species (ROS). In the bi-directional transport assay, f9 displayed proper blood-brain barrier (BBB) permeability. In addition, the title compound improved memory and cognitive functions in a mouse model induced by scopolamine. Hence, the compound f9 can be considered as a promising lead compound for further investigation in the treatment of AD.

3.
Front Pharmacol ; 12: 772386, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34925030

RESUMO

Background: Podocyte injury has a direct causal relationship with proteinuria and glomerulosclerosis and, on a chronic level, can lead to irreversible disease progression. Podocyte injury plays a critically decisive role in the development of proteinuric kidney disease. In recent years, the research on podocyte injury has developed rapidly all over the world. However, no report has summarized the field of podocyte injury as a whole to date. Using bibliometric analysis, this study aimed to evaluate the current state of worldwide podocyte injury research in the last 30 years and identify important achievements, primary research fields, and emerging trends. Methods: Publications related to podocyte injury were retrieved from Web of Science Core Collection. HistCite, VOSviewer, CiteSpace, and the Bibliometrix Package were used for bibliometric analysis and visualization, including the analysis of the overall distribution of annual outputs, leading countries, active institutions and authors, core journals, co-cited references, and keywords. Total global citation score and total local citation score were used to assess the quality and impact of publications. Results: A total of 2,669 publications related to podocyte injury were identified. Publications related to podocyte injury tended to increase continuously. A total of 10,328 authors from 2,171 institutions in 69 countries published studies related to podocyte injury. China (39.46%) was the most prolific country, and the number of citations of studies in the United States (cited 36,896 times) ranked first. Moin A Saleem, John Cijiang He, and Zhihong Liu were the top three contributing authors, and Journal of the American Society of Nephrology and Kidney International were the most popular journals in the field. "Diabetic nephropathy" is the primary focus area of podocyte injury research, and "autophagy," "microRNA," and "inflammation" were the top keywords of emerging research hotspots, and traditional Chinese medicine monomer may be a neglected research gap. Conclusion: Our research found that global publications on podocyte injury have increased dramatically. Diabetic nephropathy is the main research field of podocyte injury, whereas autophagy, microRNA, and inflammation are the top topics getting current attention from scholars and which may become the next focus in podocyte injury research.

4.
Front Bioeng Biotechnol ; 9: 764188, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34900961

RESUMO

Phosphorus (P) is a nonrenewable resource, which is one of the major challenges for sustainable agriculture. Although phosphite (Phi) can be absorbed by the plant cells through the Pi transporters, it cannot be metabolized by plant and unable to use as P fertilizers for crops. However, transgenic plants that overexpressed phosphite dehydrogenase (PtxD) from bacteria can utilize phosphite as the sole P source. In this study, we aimed to improve the catalytic efficiency of PtxD from Ralstonia sp.4506 (PtxDR4506), by directed evolution. Five mutations were generated by saturation mutagenesis at the 139th site of PtxD R4506 and showed higher catalytic efficiency than native PtxDR4506. The PtxDQ showed the highest catalytic efficiency (5.83-fold as compared to PtxDR4506) contributed by the 41.1% decrease in the K m and 2.5-fold increase in the k cat values. Overexpression of PtxDQ in Arabidopsis and rice showed increased efficiency of phosphite utilization and excellent development when phosphite was used as the primary source of P. High-efficiency PtxD transgenic plant is an essential prerequisite for future agricultural production using phosphite as P fertilizers.

5.
Artigo em Inglês | MEDLINE | ID: mdl-34936993

RESUMO

Polycythemia vera (PV) has multiple vascular risk factors and gradual onset and is an important risk factor for stroke. The first manifestation in some patients with PV is thrombotic cerebrovascular events. However, there are few reports on polycythemia vera with multiple cerebral infarctions and cerebral microhemorrhage. The clinical and imaging features of two PV patients with multiple cerebral infarctions complicated by cerebral microhemorrhage were analyzed retrospectively in order to improve the clinical understanding of the disease.

6.
Genes Genomics ; 2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34846696

RESUMO

BACKGROUND: Albeit a relatively stable epigenetic modification, DNA methylation in plants can be repatterned and play important roles in response to biotic and abiotic stresses. However, whether DNA methylation dynamics may contribute to cope with mercury (Hg) stress in plants remains to be fully investigated. OBJECTIVE: To probe the potential roles of DNA methylation dynamics in coping with Hg stress in rice. METHODS: Whole-genome bisulfite sequencing was used to profile the DNA methylation patterns of a rice Hg-resistant line (RHg) selected from a heterozygous mutant of the DNA methyltransferase 1 gene (OsMET1+/-), together with its Hg-sensitive wild-type plants of cv. Nipponbare (Nip) under both normal and Hg stress conditions. RESULTS: Genome-wide locus-specific differential methylation regions (DMRs) were detected between RHg and Nip under normal condition, the predominant DMR patterns were CG hypo-DMRs, CHG hypo-DMRs and CHH hyper-DMRs. In both lines, more hyper- than hypo-DMRs were detected at all three sequence contexts (CG, CHG and CHH) under Hg stress relative to normal condition. Comparison of DNA methylation changes in the two lines under Hg stress indicates that RHg had a more dynamic methylome than the control (Nip). Original DMRs in RHg trended to transform to opposite status (from hyper- to hypo- or vice versa) under Hg stress condition. Gene ontology analysis revealed that Hg-resistance-related DMGs were enriched in diverse biological processes. CONCLUSIONS: Our results suggest genome-wide locus-specific DNA methylation repatterning can facilitate rapid acquisition of Hg resistance in rice.

7.
J Sci Food Agric ; 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34596914

RESUMO

BACKGROUND: Several researchers have reported that the texture of fries is affected by the fatty acid composition of oil, although the mechanism of this effect is not clear. In this regard, fries were fried in refined rapeseed oil and fully hydrogenated rapeseed oil with diverse proportions (0%, 20%, 40%, 60%, 80% and 100%) and were analyzed based on the content of moisture and oil, texture, thermal properties, crystalline properties and microstructure. RESULTS: The outcomes presented that fries fried in fully hydrogenated oil had less oil absorption and moisture loss than those fried in refined oil. The results from the texture analyzer, differential scanning calorimetry and X-ray diffraction showed that hardness, enthalpy and relative crystallinity increased with an increase in the proportion of fully hydrogenated oil. However, the peaks of starch-lipid complexes were hardly observed during frying. Furthermore, scanning electron microscopy results displayed that some physically trapped fat was observed in fries fried in mixed hydrogenated oil. Stereomicroscope images showed that the crust thickness of the fries increased slightly with an increase in the proportion of fully hydrogenated oil. CONCLUSION: Overall, the upsurge in crust thickness and oil crystals was responsible for an increase in the hardness of the fries. This indicated that the texture of fries can be manipulated by altering the fatty acid composition of the oil. © 2021 Society of Chemical Industry.

8.
Ecotoxicol Environ Saf ; 227: 112896, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34673412

RESUMO

Tri-n-butyl phosphate (TnBP), a typical alkyl organophosphate ester is widely used as an emerging flame retardant for polybrominated diphenyl ethers alternatives, but the potential toxicity and mechanism are unclear. In this study, the reproductive toxicity of TnBP and its related mechanisms were explored using the Caenorhabditis elegans (C. elegans) model. After TnBP (100-1000 µg/L) exposure, brood size and the number of fertilized eggs in the uterus in C. elegans were significantly reduced, the relative area of gonad arm and the number of total germline cells in C. elegans were significantly reduced, germ cell apoptosis and germ cell DNA damage in C. elegans were significantly increased, the level of ROS in C. elegans was significantly increased. Furthermore, TnBP exposure caused abnormal gene expressions of cell apoptosis (ced-9, ced-4 and ced-3), DNA damage (hus-1, clk-2, cep-1 and egl-1) and oxidative stress (mev-1 and gas-1). TnBP exposure can lead to reproductive ability decreased and gonad development impaired in C. elegans, the mechanism of TnBP reduced reproductive ability may be related to germ cell apoptosis, germ cell DNA damage and oxidative stress. Environmental exposure to TnBP may have potential reproductive toxicity.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animais , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Feminino , Células Germinativas , Organofosfatos
10.
Aging (Albany NY) ; 13(20): 23442-23458, 2021 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-34714255

RESUMO

OBJECTIVE: Hyperamylasemia was found in a group of patients with COVID-19 during hospitalization. However, the evolution and the clinical significance of hyperamylasemia in COVID-19, is not well characterized. DESIGN: In this retrospective cohort study, the epidemiological, demographic, laboratory, treatment and outcome information of 1,515 COVID-19 patients with available longitudinal amylase records collected from electronic medical system were analyzed to assess the prevalence and clinical significance of hyperamylasemia in this infection. Associated variables with hyperamylasemia in COVID-19 were also analyzed. RESULTS: Of 1,515 patients, 196 (12.9%) developed hyperamylasemia, among whom 19 (1.3%) greater than 3 times upper limit of normal (ULN) and no clinical acute pancreatitis was seen. Multivariable ordered logistic regression implied older age, male, chronic kidney disease, several medications (immunoglobin, systemic corticosteroids, and antifungals), increased creatinine might be associated with hyperamylasemia during hospitalization. Restricted cubic spline analysis indicated hyperamylasemia had a J-shaped association with all-cause mortality and the estimated hazard ratio per standard deviation was 2.85 (2.03-4.00) above ULN. Based on the multivariable mixed-effect cox or logistic regression model taking hospital sites as random effects, elevated serum amylase during hospitalization was identified as an independent risk factor associated with in-hospital death and intensive complications, including sepsis, cardiac injury, acute respiratory distress syndrome, and acute kidney injury. CONCLUSIONS: Elevated serum amylase was independently associated with adverse clinical outcomes in COVID-19 patients. Since early intervention might change the outcome, serum amylase should be monitored dynamically during hospitalization.


Assuntos
Amilases/sangue , COVID-19/diagnóstico , Mortalidade Hospitalar , Hiperamilassemia/complicações , SARS-CoV-2/isolamento & purificação , Doença Aguda , Idoso , COVID-19/sangue , COVID-19/mortalidade , COVID-19/terapia , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Hiperamilassemia/sangue , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , SARS-CoV-2/genética
11.
Vet Sci ; 8(9)2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34564592

RESUMO

Fructus Ligustri Lucidi (FLL) is the fruit of Ligustrum lucidum Ait and is a component of many kidney-tonifying traditional Chinese medicine formulae for treating osteoporosis. Accumulating evidence has linked oxidative stress with the progression of bone diseases. The present study aimed to identify the effects of FLL on oxidative stress-related osteoporosis in vivo and in vitro. To construct animal models, we utilized d-galactose (D-gal) injection to induce oxidative stress combined with a low calcium (the exact percentage in the diet was 0.1%) diet. Thirteen-week-old Kunming female mice were gavaged with water extract of FLL for 20 days. Then, eight-month-old Kunming female mice were treated with FLL under standard administration and diet as the aged group. In vitro, MC3T3-E1 cells stimulated by H2O2 were treated with FLL for 24 h. The micro-CT results showed that the modeling approach combining oxidative stress with a low calcium diet caused low conversion type osteoporosis in mice. FLL exerted a prominent effect on preventing osteoporosis by inhibiting oxidative stress, increasing bone mineral density (BMD), improving bone microstructure, and promoting osteoblast proliferation and osteoprotegerin (OPG) protein expression; however, FLL had no therapeutic effect on bone loss in aged mice. In conclusion, FLL showed outstanding anti-bone loss ability both in vivo and in vitro and could probably be developed as a prophylactic agent for osteoporosis.

12.
J Neuroinflammation ; 18(1): 211, 2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34530836

RESUMO

BACKGROUND: Central post-stroke pain (CPSP) is a chronic and intolerable neuropathic pain syndrome following a cerebral vascular insult, which negatively impacts the quality of life of stroke survivors but currently lacks efficacious treatments. Though its underlying mechanism remains unclear, clinical features of hyperalgesia and allodynia indicate central sensitization due to excessive neuroinflammation. Recently, the crosslink between neuroinflammation and endoplasmic reticulum (ER) stress has been identified in diverse types of diseases. Nevertheless, whether this interaction contributes to pain development remains unanswered. Epoxyeicosatrienoic acids (EETs)/soluble epoxy hydrolase inhibitors (sEHi) are emerging targets that play a significant role in pain and neuroinflammatory regulation. Moreover, recent studies have revealed that EETs are effective in attenuating ER stress. In this study, we hypothesized that ER stress around the stroke site may activate glial cells and lead to further inflammatory cascades, which constitute a positive feedback loop resulting in central sensitization and CPSP. Additionally, we tested whether EETs/sEHi could attenuate CPSP by suppressing ER stress and neuroinflammation, as well as their vicious cycle, in a rat model of CPSP. METHODS: Young male SD rats were used to induce CPSP using a model of thalamic hemorrhage and were then treated with TPPU (sEHi) alone or in combination with 14,15-EET or 14,15-epoxyeicosa-5(Z)-enoic acid (14,15-EEZE, the EET antagonist), tunicamycin (Tm, ER stress inducer), or 4-PBA (ER stress inhibitor). Nociceptive behaviors, ER stress markers, JNK and p38 (two well-recognized inflammatory kinases of mitogen-activated protein kinase (MAPK) signaling) expression, and glial cell activation were assessed. In addition, some healthy rats were intrathalamically microinjected with Tm or lipopolysaccharide (LPS) to test the interaction between ER stress and neuroinflammation in central pain. RESULTS: Analysis of the perithalamic lesion tissue from the brain of CPSP rats demonstrated decreased soluble epoxy hydrolase (sEH) expression, which was accompanied by increased expression of ER stress markers, including BIP, p-IRE, p-PERK, and ATF6. In addition, inflammatory kinases (p-p38 and p-JNK) were upregulated and glial cells were activated. Intrathalamic injection of sEHi (TPPU) increased the paw withdrawal mechanical threshold (PWMT), reduced hallmarks of ER stress and MAPK signaling, and restrained the activation of microglia and astrocytes around the lesion site. However, the analgesic effect of TPPU was completely abolished by 14,15-EEZE. Moreover, microinjection of Tm into the thalamic ventral posterior lateral (VPL) nucleus of healthy rats induced mechanical allodynia and activated MAPK-mediated neuroinflammatory signaling; lipopolysaccharide (LPS) administration led to activation of ER stress along the injected site in healthy rats. CONCLUSIONS: The present study provides evidence that the interaction between ER stress and neuroinflammation is involved in the mechanism of CPSP. Combined with the previously reported EET/sEHi effects on antinociception and neuroprotection, therapy with agents that target EET signaling may serve as a multi-functional approach in central neuropathic pain by attenuating ER stress, excessive neuroinflammation, and subsequent central sensitization. The use of these agents within a proper time window could not only curtail further nerve injury but also produce an analgesic effect.

13.
J Med Chem ; 64(17): 12537-12547, 2021 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-34351142

RESUMO

Triple-negative breast cancer (TNBC) has been considered the most aggressive and mortal breast cancer. Thus far, it remains an important challenge to develop TNBC targeted therapy. As revealed from numerous recent studies, ANXA2 may be a potential target to treat TNBC. In the present study, a natural product 5α-epoxyalantolactone (5α-EAL) was discovered as an anti-breast cancer stem cells (BCSCs) lead compound. Furthermore, 5α-EAL was found to be able to notably suppress the function of ANXA2 by covalently targeting cysteine 9 (Cys9) of ANXA2. To the best of our knowledge, 5α-EAL was recognized as the first small molecule functional inhibitor of ANXA2. It could significantly inhibit the formation of the heterotetrameric complex of ANXA2 and S100A10, which is capable of transporting E-cadherin (E-Ca) to the membrane. The above findings may be used as a possible strategy to develop novel anti-TNBC therapies targeting ANXA2.

14.
Brain Struct Funct ; 226(8): 2629-2650, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34357438

RESUMO

The decreased efficiency of autophagic processing in the central nervous system during aging may be a contributing factor in neurodegenerative diseases. BAG3 (Bcl2 associated athanogene 3) is a major member of the BAG family of co-molecular chaperones that mediate selective macroautophagy. Therefore, we analyzed the expression and distribution of BAG3 in the brain at postnatal 0 day (P0), P15, 1-, 2-, 9-, 12-, and 18 month-old C57BL/6 mice, thus covering almost all ages. Except for a significant steep drop in mRNA and protein levels in the cortex and hippocampus soon after birth, there were minimal differences in the expression and distribution of BAG3 among P15, M1, M2, M9, and M12 mice; however, at 18 months, BAG3 expression was significantly higher. Immunohistochemical analyses showed that BAG3 is mainly located in the neuronal cytoplasm and processes in C57BL/6 the cerebral cortex and hippocampus from P0 to M18 postnatal development. These findings indicate that BAG3 might be stable in young and middle-aged mice, but unstable in aged mice.

15.
Int J Mol Sci ; 22(15)2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34360646

RESUMO

Diabetic nephropathy (DN) is one of the most common complications in diabetes mellitus and the leading cause of end-stage renal disease. TGF-ß is a pleiotropic cytokine and has been recognized as a key mediator of DN. However, anti-TGF-ß treatment for DN remains controversial due to the diverse role of TGF-ß1 in DN. Thus, understanding the regulatory role and mechanisms of TGF-ß in the pathogenesis of DN is the initial step towards the development of anti-TGF-ß treatment for DN. In this review, we first discuss the diverse roles and signaling mechanisms of TGF-ß in DN by focusing on the latent versus active TGF-ß1, the TGF-ß receptors, and the downstream individual Smad signaling molecules including Smad2, Smad3, Smad4, and Smad7. Then, we dissect the regulatory mechanisms of TGF-ß/Smad signaling in the development of DN by emphasizing Smad-dependent non-coding RNAs including microRNAs and long-non-coding RNAs. Finally, the potential therapeutic strategies for DN by targeting TGF-ß signaling with various therapeutic approaches are discussed.


Assuntos
Nefropatias Diabéticas/patologia , Fator de Crescimento Transformador beta/metabolismo , Animais , Nefropatias Diabéticas/metabolismo , Humanos , Transdução de Sinais
16.
Entropy (Basel) ; 23(7)2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34203339

RESUMO

Coronary heart disease (CHD) is the leading cause of cardiovascular death. This study aimed to propose an effective method for mining cardiac mechano-electric coupling information and to evaluate its ability to distinguish patients with varying degrees of coronary artery stenosis (VDCAS). Five minutes of electrocardiogram and phonocardiogram signals was collected synchronously from 191 VDCAS patients to construct heartbeat interval (RRI)-systolic time interval (STI), RRI-diastolic time interval (DTI), HR-corrected QT interval (QTcI)-STI, QTcI-DTI, Tpeak-Tend interval (TpeI)-STI, TpeI-DTI, Tpe/QT interval (Tpe/QTI)-STI, and Tpe/QTI-DTI series. Then, the cross sample entropy (XSampEn), cross fuzzy entropy (XFuzzyEn), joint distribution entropy (JDistEn), magnitude-squared coherence function, cross power spectral density, and mutual information were applied to evaluate the coupling of the series. Subsequently, support vector machine recursive feature elimination and XGBoost were utilized for feature selection and classification, respectively. Results showed that the joint analysis of XSampEn, XFuzzyEn, and JDistEn had the best ability to distinguish patients with VDCAS. The classification accuracy of severe CHD-mild-to-moderate CHD group, severe CHD-chest pain and normal coronary angiography (CPNCA) group, and mild-to-moderate CHD-CPNCA group were 0.8043, 0.7659, and 0.7500, respectively. The study indicates that the joint analysis of XSampEn, XFuzzyEn, and JDistEn can effectively capture the cardiac mechano-electric coupling information of patients with VDCAS, which can provide valuable information for clinicians to diagnose CHD.

17.
Pharmacol Res Perspect ; 9(4): e00825, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34310866

RESUMO

Bronchial pneumonia in children is a common infectious disease in toddlers and infants, which may cause hyperpyrexia, pulmonary moist rales, and even respiratory failure. Traditional drugs for bronchial pneumonia in children often lead to drug resistance and side effects. Recently, naringenin has been reported to be a potential treatment for several airway inflammatory diseases due to its anti-inflammatory and anti-microbial activities. The current clinical study aimed to evaluate the safety and therapeutic effect of naringenin in treating bronchial pneumonia in children. A total of 180 eligible patients were randomly assigned into naringenin (NAR) group and azithromycin (AZI) group. All participants were required to follow a 5-day oral administration, and their serum cytokine levels were measured during the clinical intervention. After the treatment, the disappearance time of clinical symptoms, and the incidences of complications and adverse reactions were compared between the two groups. Naringenin was able to inhibit inflammation, shorten the disappearance time of clinical symptoms, reduce the incidences of bronchial pneumonia complications and related adverse reactions, and improve the health conditions of the patients. Our results suggested that naringenin was safe and beneficial to children with bronchial pneumonia, providing new insights into the clinical application of naringenin.

18.
Angew Chem Int Ed Engl ; 60(40): 21899-21904, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34331724

RESUMO

The development of active and stable platinum (Pt)-based oxygen reduction reaction (ORR) electrocatalysts with good resistance to poisoning is a prerequisite for widespread practical application of fuel cells. An effective strategy for enhancing the electrocatalytic performance is to tune or control the physicochemical state of the Pt surface. Herein, we show a general surface-engineering approach to prepare a range of nanostructured Pt alloys by coating with alloy PtBi shells. FePt@PtBi core-shell nanoparticles showed the best ORR performance with a mass activity of 0.96 A mgPt -1 and a specific activity of 2.06 mA cm-2 , respectively 7 times and 11 times those of the corresponding values for benchmark Pt/C. Moreover, FePt@PtBi shows much better tolerance to methanol and carbon monoxide than conventional Pt-based electrocatalysts. The observed comprehensive enhancement in ORR performance of FePt@PtBi can be attributed to the increased compressive strain of the Pt surface due to in-plane shearing resulting from the presence of the large Bi atoms in the surface-structured PtBi overlayers, as well as charge displacement via Pt-Bi bonding which mitigates crossover issues.

19.
BMC Public Health ; 21(1): 1220, 2021 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-34167509

RESUMO

BACKGROUND: College students were the key group we should pay more attention for acquired immune deficiency syndrome (AIDS) prevention and control in recent years in China. Few studies of HIV non-occupational post-exposure prophylaxis (nPEP) knowledge and service acceptance had been conducted among them in China. This study conducted a cross-sectional survey to understand the service acceptance of nPEP and its influencing factors among college students in the three cities of China. METHODS: A questionnaire survey was conducted to collect information on socio-demographic, behavioral characteristic, HIV/AIDS knowledge, nPEP knowledge, acceptance of nPEP services among the college students in Beijing, Shenzhen, and Kunming of China from March to April of 2019. Each participant completed an anonymous questionnaire on line by computer-assisted or mobile phone-assisted self-interview with informed consent. Multivariable logistic regression analyses identified predictors for service acceptance of nPEP. RESULTS: A total of 4698 students were surveyed with the average age of 20 years old. 98.0% (4605/4698) of them were undergraduates, 21.8%(1022/4698) had sexual intercourse; 48.6% (2282/4698) heard of nPEP, among which 4.95%(113/2282) received nPEP services. The awareness rate of HIV/AIDS knowledge was 85.6% (5495/4698) with the differences statistically significant between the three cities. The awareness rate of nPEP knowledge was 16.5% (774/4698). There were significant differences in receiving nPEP services among students of different ages, genders, sexual behaviors, and knowledge of HIV/AIDS by univariate analysis. Multivariable analyses indicated that age group of 18 and under (OR = 2.551, 95% CI = 1.153-5.646), male (OR = 3.131, 95% CI = 1.866-5.253), homosexual behavior (OR = 4.661,95%CI = 2.658-8.172), heterosexual behavior (OR = 1.676, 95% CI = 1.040-2.947), no awareness of AIDS knowledge (OR = 3.882, 95% CI = 2.371-6.356) and nPEP (OR = 4.788, 95% CI = 2.50-9.169) knowledge, were associated with the service acceptance of nPEP among the college students. CONCLUSION: The low acceptance of nPEP services was mainly affected by low level of nPEP knowledge among the college students. Further publicity and education of nPEP knowledge were necessary, as well as promotion of knowledge of HIV/AIDS prevention and treatment. More attention should be paid to the factors associated with acceptance of nPEP services.


Assuntos
Infecções por HIV , Profilaxia Pós-Exposição , Adolescente , Adulto , China , Cidades , Estudos Transversais , Feminino , Infecções por HIV/prevenção & controle , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Comportamento Sexual , Estudantes , Inquéritos e Questionários , Adulto Jovem
20.
Neural Plast ; 2021: 8841720, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34188677

RESUMO

Objective: To analyze the pattern of intrinsic brain activity variability that is altered by acupuncture compared with conventional treatment in stroke patients with motor dysfunction, thus providing the mechanism of stroke treatment by acupuncture. Methods: Chinese and English articles published up to May 2020 were searched in the PubMed, Web of Science, EMBASE, and Cochrane Library databases, China National Knowledge Infrastructure, Chongqing VIP, and Wanfang Database. We only included randomized controlled trials (RCTs) using resting-state fMRI to observe the effect of acupuncture on stroke patients with motor dysfunction. R software was used to analyze the continuous variables, and Seed-based d Mapping with Permutation of Subject Images (SDM-PSI) was used to perform an analysis of fMRI data. Findings. A total of 7 studies comprising 143 patients in the treatment group and 138 in the control group were included in the meta-analysis. The results suggest that acupuncture treatment helps the healing process of motor dysfunction in stroke patients and exhibits hyperactivation in the bilateral basal ganglia and insula and hypoactivation in motor-related areas (especially bilateral BA6 and left BA4). Conclusion: Acupuncture plays a role in promoting neuroplasticity in subcortical regions that are commonly affected by stroke and cortical motor areas that may compensate for motor deficits, which may provide a possible mechanism underlying the therapeutic effect of acupuncture.

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