Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 4.388
Filtrar
1.
Anal Methods ; 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34476425

RESUMO

A key challenge for the discrete distribution-based Förster resonance energy transfer system (D-FRET) is the reduced intensity and stability of signal probes in complex biological matrices. Here, we present a spatially confined FRET (SC-FRET) probe with a stable structure and strong signal output. It consists of multivalent FRET pairs labeled with FAM or TAMRA. In this assay, p53 DNA was chosen as a model hairpin probe (HP), and two kinds of branched DNA probes (ssDNA-FAM, ssDNA-TAMRA) were involved. Under the action of p53 DNA, the unfolded HP acts as a primer to initiate polymerization extension of KFP polymerase and cleavage of Nb.BbvCI endonuclease, which produces plenty of ssDNA (primer-DNA). The branched DNA is designed to have the same binding core and different sticky ends, the core part of which can self-assemble to form X-shaped branched DNA (X-FAM or X-TAMRA), and the sticky ends of which are complementary to the primer-DNA. Therefore, the primer-DNAs released during the polymerization cleavage process will combine a large number of X-FAM and X-TAMRA in a limited space through complementary base pairing. Fluorescence was transferred from FAM to TAMRA, and a strong FRET response was generated by the locational effects. The proposed SC-FRET system based on the multivalent assembly of branched DNA exhibited a strong FRET response with an LOD of 0.01394 pM. Importantly, it also showed a high-contrast and stable FRET response in HeLa cells. Its superior biological stability is attributed to the large steric hindrance of the compact and rigid frame of the SC-FRET probe, which helps prevent intracellular degradation and provides a powerful tool for biomedical research.

3.
Lipids Health Dis ; 20(1): 106, 2021 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-34511134

RESUMO

BACKGROUND: Proprotein convertase subtilisin kexin type 9 (PCSK9) inhibitors have been demonstrated to produce significantly greater reduction in LDL cholesterol levels and cardiovascular events than standard statin therapy. However, evidence on the impact of PCSK9 inhibitors on coronary plaque composition and morphology is limited. METHODS: In this open-label randomized study, eligible patients with intermediate coronary lesions and elevated LDL cholesterol values were randomized to either alirocumab 75 mg Q2W plus statin (atorvastatin 20 mg/day or rosuvastatin 10 mg/day) therapy or standard care. Optical coherence tomography (OCT) assessments for target lesions were obtained at baseline and at 36 weeks of follow-up. RESULTS: LDL cholesterol levels were significantly decreased in both the alirocumab and standard care arms, whereas the absolute reduction in LDL cholesterol was significantly greater in patients treated with alirocumab (1.72 ± 0.51 vs. 0.96 ± 0.59, P < 0.0001). Compared with standard care, the addition of alirocumab to statins was associated with significantly greater increases in minimum fibrous cap thickness (18.0 [10.8-29.2] µm vs 13.2 [7.4-18.6] µm; P = 0.029), greater increases in minimum lumen area (0.20[0.10-0.33] mm2 vs 0.13 [0.12-0.24] mm2; P = 0.006) and a greater diminution in maximum lipid arc (15.1̊ [7.8-24.5] vs. 8.4̊ [2.0-10.5]; P = 0.008). CONCLUSIONS: The addition of alirocumab to statins can not only provide additional LDL cholesterol lowering effects but also have a potential role in promoting a more stable plaque phenotype. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04851769 . Registered 2 Mar 2019.

4.
Food Res Int ; 148: 110614, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34507758

RESUMO

A two-dimensional low-field nuclear magnetic resonance (LF-NMR) T1-T2 relaxation technique was developed to contrast the water status evolution during different cooking procedures (steam and boiling cooking). Meat quality, water distribution, microstructure and protein properties were determined. The results showed that steamed meats had lower cooking loss and shear force, but higher redness, proton relaxation intensity (T1 and T2) and proton density than boiled meats. The differences in water distribution between the two cooking procedures appeared at approximately 40 °C, with acceleration at 60 °C, and the most remarkable difference was shown at 80 °C. Boiling resulted in more damage to muscle structure and greater protein denaturation than steam cooking. Meanwhile, α-helixes and ß-turns increased, but ß-sheets and random coils decreased in steamed meats compared with boiled meats. Changes in microstructural and protein properties were closely associated with water status evolution in cooked meat during cooking.

7.
Environ Res ; : 112032, 2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34516980

RESUMO

A novel FeVO4/BiVO4 heterojunction photocatalyst was synthesized by hydrothermal method. The FeVO4/BiVO4 nanostructures were characterized by XRD, SEM, XPS, UV-vis, and photoluminescence spectroscopy. The effects of catalyst dosage, contaminant concentration, initial hydrogen peroxide (H2O2) concentration, and pH value on the degradation of levofloxacin were investigated and several repeated experiments were conducted to evaluate the stability and reproducibility. The optimized process parameters were used for mineralization experiments. Reactive oxygen species, degradation intermediates, and possible catalytic mechanisms were also investigated. The results showed that the sonophotocatalytic performance of the FeVO4/BiVO4 heterojunction catalyst was better than that of sonocatalysis and photocatalysis. In addition, the Type II heterojunction formed by the material still had good stability in the degradation of levofloxacin after 5 cycles. The possible degradation pathway and mechanism of levofloxacin by sonophotocatalysis were put forward. This work develops new sono-photo hybrid process for potential application in the field of wastewater treatment.

8.
Talanta ; 235: 122814, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34517670

RESUMO

Simple and sensitive detection of telomerase activity is of vital importance for both early diagnosis and therapy of malignant tumors. Inspired by DNA-biobarcode amplification reported by Chad A. Mirkin, we developed a facile DNA-biobarcode-like SERS-based copper-mediated signal amplification strategy for sensitive detection of telomerase activity. In this strategy, a duplex DNA constructed by hybridization of a copper oxide nanoparticle (CuO NP)-labeled reporting sequence (RS) with the telomerase primer sequence (TS) is ingeniously designed, and anchored on the magnetic bead (MB) to build the CuO NPs-encoded magnetic bead (MB-CuO NPs) detection probe. Upon selective sensing of telomerase, telomerase elongation reaction and structure change of TS products make the CuO NP-RS displace and separate from MB. The separated CuO NPs are dissolved into a mass of Cu2+, which prompt monodisperse dopamine-functionalized AgNPs (D-AgNPs) signal probe into aggregation, resulting in color changes and significantly enhancing of SERS signal. The SERS signal increases with the increase of Cu2+, which is directly proportional to the telomerase. Benefiting from the transformation of CuO NP to Cu2+ with a high amplification effect, this strategy could realize the telomerase activity measurement down to 3 HeLa cells and a dynamic range of 10-10000 cells. It shows a significant improvement of sensitivity without need for other enzymes and elaborate design, which escapes from the complicated manipulations and design in polymerase chain reaction (PCR) and DNA amplification techniques. Moreover, with this strategy, telomerase activities of different cell lines and telomerase inhibitors screening were successfully performed. Significantly, it can also be utilized for visual detection of telomerase, which validates the potential on-site application and its application as point-of-care testing (POCT) for efficient monitoring. Given the high-performance for telomerase analysis, the strategy has a promising application in biological detection and clinical diagnosis, as well as point-of-care tests.

9.
J Immunol Res ; 2021: 6149558, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34476262

RESUMO

N6-Methyladenosine (m6A) modification is one of the commonest chemical modifications in eukaryotic mRNAs, which has essential effects on mRNA translation, splicing, and stability. Currently, there is a rising concern on the regulatory role of m6A in tumorigenesis. As a known component in the m6A methyltransferase complex, METTL3 (methyltransferase-like 3) plays an essential role in m6A methylation. Till now, the functions of METTL3 in oral squamous cell carcinoma (OSCC) and its relative mechanism remain to be explored. In this research, through the GEPIA database, we found that high METTL3 expression has a correlation with poor prognosis of squamous cell carcinoma of head and neck. qRT-PCR displayed that METTL3 was highly expressed in OSCC cells. Functionally, METTL3 knockdown reduced the invasion, migration, and proliferation competence of OSCC cells and attenuated the activation of CD8+ T cells. In contrast, METTL3 overexpression resulted in opposite results. GEPIA, UALCAN, and SRAMP databases, PCR, western blot, and m6A RNA methylation assay confirmed the m6A modification of PRMT5 and PD-L1 mediated by METTL3. In conclusion, our results displayed that METTL3 intensified the metastasis and proliferation of OSCC by modulating the m6A amounts of PRMT5 and PD-L1, suggesting that METTL3 may be a therapeutic target for OSCC patients.

10.
Immunol Lett ; 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34480980

RESUMO

Leptin is over-secreted in many autoimmune diseases, which can promote dendritic cells (DCs) maturation and up-regulate the expression of inflammatory cytokines, but the underlying mechanisms are not fully elucidated. Considering the major role of leptin in maintaining energy balance and the significant role of glycolysis in DCs activation, our study aims to investigate whether leptin promotes the activation of DCs via glycolysis and its underlying mechanisms. We demonstrated that leptin promoted the activation of DCs, including up-regulating the expression of co-stimulatory molecules and inflammatory cytokines, enhancing the proliferation and T helper 17 (Th17) cell ratio in peripheral blood mononuclear cells (PBMC) co-cultured with leptin-stimulated DCs. Leptin also enhanced DCs glycolysis with increased glucose consumption, lactate production, and the expression of hexokinase 2 (HK2). In addition, the activation of DCs stimulated by leptin could be inhibited by the glycolysis inhibitor 2-deoxy-D-glucose (2-DG). To explore the signaling pathways involved in leptin-induced HK2 expression, we observed that the inhibitors of STAT3 (NSC74859) could repress the enhancement of HK2 triggered by leptin stimulation. Therefore, our results indicated that leptin promoted glycolytic metabolism to induce DCs activation via STAT3-HK2 pathway.

11.
Biol Res ; 54(1): 27, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34488902

RESUMO

BACKGROUND: Demethylzeylasteral (T-96) is a pharmacologically active triterpenoid monomer extracted from Tripterygium wilfordii Hook F (TWHF) that has been reported to exhibit anti-neoplastic effects against several types of cancer cells. However, the potential anti-tumour effects of T-96 against human Prostate cancer (CaP) cells and the possible underlying mechanisms have not been well studied. RESULTS: In the current study, T-96 exerted significant cytotoxicity to CaP cells in vitro and induced cell cycle arrest at S-phase in a dose-dependent manner. Mechanistically, T-96 promoted the initiation of autophagy but inhibited autophagic flux by inducing ROS-mediated endoplasmic reticulum (ER) stress which subsequently activated the extrinsic apoptosis pathway in CaP cells. These findings implied that T-96-induced ER stress activated the caspase-dependent apoptosis pathway to inhibit proliferation of CaP cells. Moreover, we observed that T-96 enhances the sensitivity of CaP cells to the chemotherapeutic drug, cisplatin. CONCLUSIONS: Taken together, our data demonstrated that T-96 is a novel modulator of ER stress and autophagy, and has potential therapeutic applications against CaP in the clinic.


Assuntos
Autofagia , Neoplasias da Próstata , Apoptose , Linhagem Celular Tumoral , Humanos , Masculino , Neoplasias da Próstata/tratamento farmacológico , Espécies Reativas de Oxigênio , Triterpenos
12.
J Immunol Res ; 2021: 6203759, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34497859

RESUMO

Background: Oral squamous cell carcinoma (OSCC) is the most common type of oral cancer, which remains a major cause of morbidity and mortality in patients with head and neck cancers. However, the critical immune-related signatures and their prognostic values have rarely been investigated. Materials and Methods: Gene differential analysis was used to measure the differences of gene expression between the groups. Correlation analysis was used to assess the association between the gene expression levels and immune-related risk score/DNA methylation levels. The gene set enrichment analysis (GSEA) was used to identify the pathways or cell types enriched by those identified differentially expressed genes (DEGs). Results: In this study, we identified four immune-related gene signatures, including CTSG, TNFRSF4, LCORL, and PLAU, that were significantly associated with the overall survival in OSCC patients from the Cancer Genome Atlas (TCGA) OSCC cohort. Moreover, these four immune-related signatures were differentially expressed between the OSCC and nontumor tissues. The two groups (high and low risk) stratified by the immune-related risk scores had significantly different OS and mortality rates. The gene expression patterns and prognostic values of these immune-related signatures were also verified in two independent validation cohorts. Furthermore, the downregulated genes in the high-risk group (which were also upregulated in the low-risk group) were significantly enriched in the cell type-specific signatures of type 2 T helper cell (Th2), plasmacytoid dendritic cell (pDC), and memory B cell. In contrast, the upregulated genes in the high-score group were enriched in growth factor receptor-related signaling pathways, such as the VEGFA-VEGFR2 signaling pathway, PI3K-Akt signaling pathway, focal adhesion-PI3K-Akt-mTOR signaling pathway, and PDGF pathway, suggesting that those pathways were inversely correlated with immune cell infiltration. Conclusion: In summary, the immune-related signatures had the potential for predicting the risk of OSCC patients. Moreover, the present study also improved our understanding of the association between the growth factor receptor pathways and immune cell infiltration in OSCC.

13.
JMIR Mhealth Uhealth ; 9(9): e29498, 2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34499047

RESUMO

BACKGROUND: Diabetes has placed heavy social and economic burdens on society and families worldwide. Insufficient knowledge and training of frontline medical staff, such as nurses, interns, and residents, may lead to an increase in acute and chronic complications among patients with diabetes. However, interns have insufficient knowledge about diabetes management. The factors that affect interns' current level of diabetes-related knowledge are still unclear. Therefore, understanding the behavioral intentions of interns is essential to supporting the development and promotion of the use of virtual simulation teaching applications. OBJECTIVE: This study aimed to identify the determinants of nursing interns' intentions to use simulation-based education applications. METHODS: From December 1, 2020, to February 28, 2021, the web-based survey tool Sojump (Changsha Xingxin Information Technology Co) was used to survey nursing interns in hospitals across China. Two survey links were sent to 37 partner schools in 23 major cities in China, and they were disseminated through participants' WeChat networks. Multiple regression analysis was used to determine the association between demographic information and basic disease information and the use of the application for treating adult patients. RESULTS: Overall, 883 nursing interns from 23 provinces in China responded to the survey. Among them, the virtual simulation utilization rate was 35.6% (314/883) and the awareness rate was 10.2% (90/883). In addition, among the interns, only 10.2% (90/883) correctly understood the concept of virtual simulation, and most of them (793/883, 89.8%) believed that scenario-simulation training or the use of models for teaching are all the same. Multiple regression analysis showed that the educational level, independent learning ability, and professional identity of the interns were related to use of the application (P<.05). Skills and knowledge that the interns most wanted to acquire included the treatment of hypoglycemia (626/883, 70.9%), functional test simulation (610/883, 69.1%), and blood glucose monitoring technology (485/883, 54.9%). A total of 60.5% (534/883) of the interns wanted to acquire clinical thinking skills, while 16.0% (141/883) wanted to acquire operational skills. Nursing trainees believed that the greatest obstacles to virtual simulation included limited time (280/883, 31.7%), the degree of simulation (129/883, 14.6%), the demand for satisfaction (108/883, 12.2%), and test scores (66/883, 7.5%). CONCLUSIONS: The understanding and usage rate of diabetes virtual simulation teaching applications by Chinese nursing interns is very low. However, they have high requirements regarding this teaching method. Conducting high-quality randomized controlled trials and designing applications that are suitable for the needs of different nurse trainees will increase students' interest in learning and help improve diabetes knowledge among nursing interns.

14.
BMC Med ; 19(1): 190, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34465315

RESUMO

BACKGROUND: Triple-negative breast cancer (TNBC) is a clinically aggressive disease with abundant variants that cause homologous recombination repair deficiency (HRD). Whether TNBC patients with HRD are sensitive to anthracycline, cyclophosphamide and taxane (ACT), and whether the combination of HRD and tumour immunity can improve the recognition of ACT responders are still unknown. METHODS: Data from 83 TNBC patients in The Cancer Genome Atlas (TCGA) was used as a discovery cohort to analyse the association between HRD and ACT chemotherapy benefits. The combined effects of HRD and immune activation on ACT chemotherapy were explored at both the genome and the transcriptome levels. Independent cohorts from the Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) and Gene Expression Omnibus (GEO) were adopted to validate our findings. RESULTS: HRD was associated with a longer ACT chemotherapy failure-free interval (FFI) with a hazard ratio of 0.16 (P = 0.004) and improved patient prognosis (P = 0.0063). By analysing both HRD status and ACT response, we identified patients with a distinct TNBC subtype (ACT-S&HR-P) that showed higher tumour lymphocyte infiltration, IFN-γ activity and NK cell levels. Patients with ACT-S&HR-P had significantly elevated immune inhibitor levels and presented immune activation associated with the increased activities of both innate immune cells and adaptive immune cells, which suggested treatment with immune checkpoint blockade as an option for this subtype. Our analysis revealed that the combination of HRD and immune activation enhanced the efficiency of identifying responders to ACT chemotherapy (AUC = 0.91, P = 1.06e-04) and synergistically contributed to the clinical benefits of TNBC patients. A transcriptional HRD signature of ACT response-related prognostic factors was identified and independently validated to be significantly associated with improved survival in the GEO cohort (P = 0.0038) and the METABRIC dataset (P < 0.0001). CONCLUSIONS: These findings highlight that HR deficiency prolongs FFI and predicts intensified responses in TNBC patients by combining HRD and immune activation, which provides a molecular basis for identifying ACT responders.

15.
Medicine (Baltimore) ; 100(35): e26201, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34477113

RESUMO

ABSTRACT: This retrospective study appraised the preventive effect of statin after carotid artery stenting (CAS).Records were extracted for 100 patients with CAS surgery indicator, aged between 20 and 75 years old, and treated for statin. The cohort study included treatment group (statin and routine treatment) and control group (routine treatment), each group 50 patients. Outcomes consisted of degree of nerve defect (as measured by National Institute of Health Stroke Scale), lipid profiles (mg/dL), and CAS complications within 30 days after surgery.After treatment, there were no significant differences in National Institute of Health Stroke Scale, lipid profiles, and mortality rate between 2 groups. However, significant differences in total cholesterol (mg/dL, P = .03), low-density lipoprotein (mg/dL, P = .01), transient ischemic attack (P = .03), ischemic stroke (P = .04), and cardiac complications (P = .03) were identified within 30 days after CAS between 2 groups.The results of this study showed that prior statin treatment may be effective for the prevention of CAS complications.


Assuntos
Artérias Carótidas/efeitos dos fármacos , Inibidores de Hidroximetilglutaril-CoA Redutases/normas , Stents/normas , Idoso , Artérias Carótidas/fisiopatologia , China/epidemiologia , Estudos de Coortes , Feminino , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Estatísticas não Paramétricas , Stents/estatística & dados numéricos , Resultado do Tratamento
16.
Molecules ; 26(17)2021 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-34500814

RESUMO

The investigation of the constituents of the rhizomes of Dioscorea collettii afforded one new dihydroisocoumarin, named (-)-montroumarin (1a), along with five known compounds-montroumarin (1b), 1,1'-oxybis(2,4-di-tert-butylbenzene) (2), (3R)-3'-O-methylviolanone (3a), (3S)-3'-O-methylviolanone (3b), and (RS)-sativanone (4). Their structures were elucidated using extensive spectroscopic methods. To the best of our knowledge, compound 1a is a new enantiomer of compound 1b. The NMR data of compound 2 had been reported but its structure was erroneous. The structure of compound 2 was revised on the basis of a reinterpretation of its NMR data (1D and 2D) and the assignment of the 1H and 13C NMR data was given rightly for the first time. Compounds 3a-4, three dihydroisoflavones, were reported from the Dioscoreaceae family for the first time. The cytotoxic activities of all the compounds were tested against the NCI-H460 cell line. Two dihydroisocoumarins, compounds 1a and 1b, displayed moderate cytotoxic activities, while the other compounds showed no cytotoxicity.

17.
Psychosom Med ; 2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34334732

RESUMO

OBJECTIVE: This study aimed to investigate whether patients with juvenile-onset type 1 diabetes mellitus (T1DM) have poorer sustained attention than their counterparts with adult-onset T1DM, and whether there is a relationship between diabetes-related variables and sustained attention. METHODS: This study included 76, 68, and 85 participants with juvenile-onset and adult-onset T1DM, and healthy controls (HCs), respectively. All participants completed the Sustained Attention to Response Task, Beck Depression Inventory-II, and the Chinese version of the Wechsler Adult Intelligence Scale. RESULTS: The juvenile-onset group showed more omission errors (p = .007) than the adult-onset group and shorter reaction time (p = .005) than HCs, while the adult-onset group showed no significant differences compared with HCs. Hierarchical linear regression analysis revealed that the age of onset was associated with omission errors in T1DM participants (ß = -0.275, t = -2.002, p = .047). In the juvenile-onset group, the omission error rate were associated with the history of severe hypoglycemia (ß = 0.225, t = 1.996, p = .050), while reaction time was associated with the age of onset (ß = -0.251, t = -2.271, p = .026). Fasting blood glucose levels were significantly associated with reaction time in both the juvenile-onset and adult-onset groups (ß = -0.236, t = -2.117, p = .038 and ß = 0.259, t = 2.041, p = .046, respectively). CONCLUSION: Adults with juvenile-onset T1DM have sustained attention deficits, in contrast to their adult-onset counterparts, suggesting that the disease adversely affects the developing brain. Both the history of severe hypoglycemia and fasting blood glucose levels are factors associated with sustained attention impairment. Early diagnosis and treatment in juvenile patients are required to prevent the detrimental effects of diabetes.

18.
Mol Med Rep ; 24(4)2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34396443

RESUMO

The ectopic proliferation, migration and invasion of vascular smooth muscle cells (VSMCs) contributes to the progression of various human vascular diseases. Accumulating evidence has demonstrated that microRNAs (miRs) exert vital functions in the proliferation and invasion of VSMCs. The current study aimed to elucidate the functions of miR­125a­5p and miR­7 in VSMCs and investigate the associated molecular mechanisms. The results of EdU and reverse transcription­quantitative PCR assays revealed that platelet­derived growth factor (PDGF)­BB enhanced the proliferation of VSMCs and significantly reduced the expression of miR­125a­5p and miR­7. miR­125a­5p or miR­7 overexpression significantly ameliorated PDGF­BB­induced proliferation, migration and invasion of VSMCs. Furthermore, the results demonstrated that epidermal growth factor receptor (EGFR) may be a target mRNA of miR­125a­5p and miR­7 in VSMCs. The results of western blot analysis indicated that co­transfection of miR­125a­5p mimics or miR­7 mimics distinctly decreased the protein expression of EGFR in EGFR­overexpressed VSMCs. Moreover, rescue experiments indicated that EGFR overexpression alleviated the suppressive impact of the miR­125a­5p and miR­7 s on the growth, migration and invasion of VSMCs. In conclusion, the current study identified that miR­125a­5p and miR­7 repressed the growth, migration and invasion of PDGF­BB­stimulated VSMCs by, at least partially, targeting EGFR. The current study verified that miR­125a­5p and miR­7 may be used as feasible therapeutic targets for cardiovascular diseases.

19.
Molecules ; 26(16)2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34443627

RESUMO

The importance of yeast old yellow enzymes is increasingly recognized for direct asymmetric reduction of (E/Z)-citral to (R)-citronellal. As one of the most performing old yellow enzymes, the enzyme OYE3 from Saccharomyces cerevisiae S288C exhibited complementary enantioselectivity for the reduction of (E)-citral and (Z)-citral, resulting in lower e.e. value of (R)-citronellal in the reduction of (E/Z)-citral. To develop a novel approach for the direct synthesis of enantio-pure (R)-citronellal from the reduction of (E/Z)-citral, the enzyme OYE3 was firstly modified by semi-rational design to improve its (R)-enantioselectivity. The OYE3 variants W116A and S296F showed strict (R)-enantioselectivity in the reduction of (E)-citral, and significantly reversed the (S)-enantioselectivity in the reduction of (Z)-citral. Next, the double substitution of OYE3 led to the unique variant S296F/W116G, which exhibited strict (R)-enantioselectivity in the reduction of (E)-citral and (E/Z)-citral, but was not active on (Z)-citral. Relying on its capability discriminating (E)-citral and (Z)-citral, a new cascade reaction catalyzed by the OYE3 variant S296F/W116G and glucose dehydrogenase was developed, providing the enantio-pure (R)-citronellal and the retained (Z)-citral after complete reduction of (E)-citral.

20.
Artigo em Inglês | MEDLINE | ID: mdl-34461084

RESUMO

OBJECTIVE: To evaluate the effectiveness of mirror therapy (MT) for phantom limb pain (PLP). DATA SOURCES: PubMed, EMBASE, Ovid MEDLINE, Scopus, Cochrane Library, Physiotherapy Evidence Database, CNKI, and WanFang Data were used to search for studies published up to March 31, 2021. STUDY SELECTION: Randomized controlled trials (RCTs) comparing the pain intensity of MT for PLP were performed. A total of 2094 articles were found. Among them, 10 were eligible for the final analysis. DATA EXTRACTION: The quality of the RCTs was assessed using the PEDro scale by two independent reviewers. Outcome data were pooled according to follow-up intervals (1, 3, 6, and 12 months). Duration times were used as a basis for distinguishing subgroups. The primary evaluation was by visual analog scale (VAS). The PEDro scale was used to assess the methodological quality of studies. DATA SYNTHESIS: Meta-analysis revealed a statistically significant decrease in pain in the MT group versus the control group within 1 month (I2 = 0%, SMD = -0.46, 95% CI: -0.79--0.13, p = 0.007). The patients with pain for longer than one year benefited more from MT (I2 = 0%, SMD = -0.46, 95% CI: -0.85--0.07, p = 0.02). CONCLUSIONS: MT has beneficial effects for patients suffering from PLP in the short-term, as evidenced by their improved pain scores. There was no evidence that MT had a long-term effect, but that may be a product of limited data. For patients with long-term PLP, MT may be an effective treatment.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...