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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 244: 118781, 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-32891898

RESUMO

By choosing C3 symmetric 2,4,6-tris-(4-carboxyphenyl)-1,3,5-triazine (TCTZ) as the ligand, a series of lanthanide metal-origanic complexes Tb1-xEux-TCTZ(DMF)·2H2O(x = 0, 0.01, 1) have been successfully synthesized via solvothermal reaction. The complexes present intense emission although with coordinationofwater molecules. The temperature-dependent photoluminescent (PL) properties of Tb-TCTZ is investigated both in terms of emission intensity and lifetime in order to establish their potentials as luminescent themometers. It shows excellent responseto temperature from 303 to 403 K and exhibits the maximum relative sensitivity(Sr) as high as 5.36% K-1 at 403 K. Tb0.99Eu0.01-TCTZ is evaluated for application as ratiometric luminescence thermometers, which exhibits high sensitivity to temperature in range of 303-403 K, with the maximum absolute sensitivity (Sa) and Sr as 5.16% and 3.22% K-1 respectively. The obtained maximum sensitivities in this study is superior to many materials reported. Moreover, the emission color changes from green at 303 K to red at 403 K, so that it is also suitable to act as colorimetric luminescent probes.

2.
Food Chem ; 336: 127672, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32771899

RESUMO

Endophytic bacteria are always related to the host different traits, including the secondary metabolites production. However, the effect and mechanism of endophytic bacteria in the mushrooms fruit body on mycelia are still not clear. In this study, we investigated the effect of endophytic bacterial metabolites on the quality of Lyophyllum decastes mycelia. Soluble sugars, starch, protein, free amino acids, 5'-Nucleotides, EUC, and organic acids contents of mycelia were analyzed. We found that endophytic bacterial metabolites significantly increased the contents of soluble sugars, starch, protein, free amino acids, organic acids, and EUC. The present study thus suggests that endophytic bacteria could promote the quality of Lyophyllum decastes by improving non-volatile taste components of mycelia.


Assuntos
Agaricales/química , Bactérias/metabolismo , Endófitos/fisiologia , Micélio/química , Paladar , Agaricales/fisiologia , Aminoácidos/análise , Bactérias/isolamento & purificação , Microbiologia de Alimentos , Qualidade dos Alimentos , Proteínas Fúngicas/análise , Micélio/fisiologia , Nucleotídeos/análise , Compostos Orgânicos Voláteis
3.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 37(5): 903-909, 2020 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-33140616

RESUMO

Cognitive enhancement refers to the technology of enhancing or expanding the cognitive and emotional abilities of people without psychosis based on relevant knowledge of neurobiology. The common methods of cognitive enhancement include transcranial direct current stimulation (tDCS) and cognitive training (CT). tDCS takes effect quickly, with a short effective time, while CT takes longer to work, requiring several weeks of training, with a longer effective time. In recent years, some researchers have begun to use the method of tDCS combined with CT to regulate the cognitive function. This paper will sort out and summarize this topic from five aspects: perception, attention, working memory, decision-making and other cognitive abilities. Finally, the application prospect and challenges of technology are prospected.

4.
Chem Biol Drug Des ; 2020 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-33219736

RESUMO

A novel series of hybrids designed on the basis of aurantiamide acetate and isopropylated genipin were synthesized and biologically evaluated as anti-inflammatory agents. Among them, compound 7o exhibited the best inhibitory activity against TNF-α secretion (IC50 = 16.90 µM), and was selected for further in vitro and in vivo functional study. The results demonstrated that 7o was capable of suppressing the expression of LPS-induced iNOS and COX-2, as well as reducing the production of NO at the concentration of 5 µM, which may be resulted from its regulation of NF-κB signaling and MAPK signaling. Moreover, compound 7o exhibited favourable in vivo anti-inflammatory activity with an inhibition rate of 53.32% against xylene-induced ear swelling in mice at the dose of 5 mg/kg.

5.
Eur Neurol ; : 1-10, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-33130678

RESUMO

Stroke is one of the leading causes of mortality and disability worldwide. Long noncoding RNAs (lncRNAs) including MALAT1 have been shown to have critical roles in cerebral ischemia reperfusion injury (CIRI). However, the underlying mechanism of MALAT1 in CIRI has not been elucidated. The present study aimed to investigate the function and potential regulatory mechanism of MALAT1 in cerebral ischemic reperfusion injury. We established the middle cerebral artery occlusion (MCAO) model and oxygen-glucose deprivation/reoxygenation (OGD/RX) model in vivo and in vitro, and then Cell Counting Kit-8 (CCK-8), RT-qPCR, flow cytometry analysis, lactate dehydrogenase (LDH) analysis, and 2,3,5-triphenyltetrazolium chloride (TTC) staining were used to examine cell viability, MALAT1, aquaporin-4 (AQP4) expression, LDH release, and infarct volume, respectively. The level of AQP4 was remarkably upregulated in CIRI 24 h/48 h or OGD/RX 24 h/48 h compared with the sham group. Knockdown of AQP4 could alleviate OGD/RX-induced injury through enhancing cell viability and reducing LDH release and the rate of apoptotic cells. Furthermore, we found that MALAT1 was also increased in OGD/RX 24 h/48 h and silencing of MALAT1 could decrease AQP4. Inhibition of MALAT1 could also protect OGD/RX-induced injury, while the protective effect of MALAT1 siRNA on cerebral ischemic reperfusion was disappeared after transfection with AQP4 plasmid, indicating that MALAT1 may play a protective role in brain stroke through regulating AQP4. Taken together, our study provides evidence that MALAT1 is involved in ischemic stroke by inhibiting AQP4. Therefore, MALAT1 may serve as a potential target for therapeutic intervention in ischemic brain injury.

6.
Ann Clin Lab Sci ; 50(5): 591-599, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33067205

RESUMO

Treatment-free remission (TFR) is emerging as a new therapy goal for chronic myeloid leukemia (CML) patients in the tyrosine kinase inhibitors (TKI) era. Data indicates the unfavorable success rate of TFR. This study aimed to compare and evaluate the clinical value of dd-PCR in predicting relapse in CML patients entering TFR. Using dd-PCR and RT-qPCR technology, dynamic BCR/ABL transcripts were detected in 13 CML patients who discontinued TKI treatment after sustaining undetectable BCR-ABL levels for a median time of 25 months. The results showed that in 13 patients, only 2 cases (22.2%) of 9 patients who executed planned discontinuation achieved TFR within 12 months. In the first 6 months, the detection rate of BCR/ABL transcripts by dd-PCR was higher than that by RT-qPCR and the two methods kept a positive correlation (r=0.9651, P=0.0349). Meanwhile, the time of detectable BCR/ABL by dd-PCR were significantly shorter (P<0.05), which was an average of 2.98 months earlier than RT-qPCR. The total TKI therapy and MR4.5 duration time related with TFR were longer in patients with intermediate or high Sokal risk scores (p<0.05). The dd-PCR could be more sensitive than RT-qPCR for monitoring BCR/ABL transcripts of CML patients with deep molecular response to TKI. The technique can be used as a preferred method to detect the transcripts in the first 6 months after TKI cessation.

7.
Sci Total Environ ; : 142191, 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-33097254

RESUMO

Diabetic patients often have a heightened risk of cardiomyopathy, even in the absence of traditional risk factors such as hypertension and atherosclerotic coronary artery disease. Diabetic cardiomyopathy is characterized by a typical cardiomyopathy specific to diabetes, the pathogenesis of which has yet to be fully elucidated. As a well-documented oncogenic long noncoding RNA (lncRNA), metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) has been implicated in a variety of pathological processes, including diabetic complications. This study aimed to evaluate the functional roles of MALAT1 in the pathogenesis of diabetic cardiomyopathy. Spontaneously diabetic (db/db) C57BL/Ks mice were employed to establish diabetic cardiomyopathy models in vivo and high glucose (HG)-cultured mouse cardiomyocytes for myocardial damage models in vitro. Mouse left ventricular volume and function were evaluated by echocardiography, while the myocyte cross-sectional area was calculated to evaluate the degree of myocardial hypertrophy. TUNEL staining and flow cytometric analysis were performed to evaluate myocardial damage and cardiomyocyte apoptosis. Silencing of MALAT1 was found to attenuate cardiac dysfunction and inhibit cardiomyocyte apoptosis in db/db mice and HG-cultured mouse cardiomyocytes. MALAT1 recruited the histone methyltransferase EZH2 to the miR-22 promoter region and inhibited its expression. EZH2 induced an increased in the expression of ATP-binding cassette transporter A1 (ABCA1), which was identified to be a target gene of miR-22. Silencing of EZH2 was found to improve cardiac function and prevent cardiomyocyte apoptosis in db/db mice and HG-cultured mouse cardiomyocytes in the presence of MALAT1, suggesting that MALAT1 mediated myocardial damage by recruiting EZH2 to the miR-22 promoter. Taken together, this study's findings provide evidence confirming our hypothesis, suggesting the involvement of MALAT1 in the processes of cardiac function and cardiomyocyte apoptosis via the EZH2/miR-22/ABCA1 signaling cascade, which has potential therapeutic implications for the understanding of diabetic cardiomyopathy.

8.
World J Surg Oncol ; 18(1): 275, 2020 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-33099304

RESUMO

BACKGROUND: Few studies have focused on the role of hepatectomy for colorectal liver-limited metastases in elderly patients compared to matched younger patients. METHODS: From January 2000 to December 2018, 724 patients underwent hepatectomy for colorectal liver-limited metastases. Based on a 1:2 propensity score matching (PSM) model, 64 elderly patients (≥ 70 years of age) were matched to 128 younger patients (< 70 years of age) to obtain two balanced groups with regard to demographic, therapeutic, and prognostic factors. RESULTS: There were 73 elderly and 651 younger patients in the unmatched cohort. Compared with the younger group (YG), the elderly group (EG) had significantly higher proportion of American Society of Anesthesiologists score III and comorbidities and lower proportion of more than 3 liver metastases and postoperative chemotherapy (p < 0.05). After PSM for these factors, rat sarcoma virus proto-oncogene/B-Raf proto-oncogene (RAS/BRAF) mutation status and primary tumor sidedness, the EG had significantly less median intraoperative blood loss than the YG (175 ml vs. 200 ml, p = 0.046), a shorter median postoperative hospital stay (8 days vs. 11 days, p = 0.020), and a higher readmission rate (4.7% vs.0%, p = 0.036). The EG also had longer disease-free survival (DFS), overall survival (OS), and cancer-specific survival (CSS) compared to the YG, but these findings were not statistically significant (p > 0.05). Old age was not an independent factor for DFS, OS, and CSS by Cox multivariate regression analysis (p > 0.05). CONCLUSIONS: Hepatectomy is safe for colorectal liver-limited metastases in elderly patients, and these patients may subsequently benefit from prolonged DFS, OS, and CSS.

9.
Microb Cell Fact ; 19(1): 187, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33008397

RESUMO

Mycobacterium neoaurum strains can transform phytosterols to 4-androstene-3,17-dione (4-AD), a key intermediate for the synthesis of advanced steroidal medicines. In this work, we presented the complete genome sequence of the M. neoaurum strain HGMS2, which transforms ß-sitosterol to 4-AD. Through genome annotation, a phytosterol-degrading pathway in HGMS2 was predicted and further shown to form a 9,10-secosteroid intermediate by five groups of enzymes. These five groups of enzymes included three cholesterol oxidases (ChoM; group 1: ChoM1, ChoM2 and Hsd), two monooxygenases (Mon; group 2: Mon164 and Mon197), a set of enzymes for side-chain degradation (group 3), one 3-ketosteroid-1,2-dehydrogenase (KstD; group 4: KstD211) and three 3-ketosteroid-9a-hydroxylases (Ksh; group 5: KshA226, KshA395 and KshB122). A gene cluster encoding Mon164, KstD211, KshA226, KshB122 and fatty acid ß-oxidoreductases constituted one integrated metabolic pathway, while genes encoding other key enzymes were sporadically distributed. All key enzymes except those from group 3 were prepared as recombinant proteins and their activities were evaluated, and the proteins exhibited distinct activities compared with enzymes identified from other bacterial species. Importantly, we found that the KstD211 and KshA395 enzymes in the HGMS2 strain retained weak activities and caused the occurrence of two major impurities, i.e., 1,4-androstene-3,17-dione (ADD) and 9-hydroxyl-4-androstene-3,17-dione (9OH-AD) during ß-sitosterol fermentation. The concurrence of these two 4-AD analogs not only lowered 4-AD production yield but also hampered 4-AD purification. HGMS2 has the least number of genes encoding KstD and Ksh enzymes compared with current industrial strains. Therefore, HGMS2 could be a potent strain by which the 4-AD production yield could be enhanced by disabling the KstD211 and KshA395 enzymes. Our work also provides new insight into the engineering of the HGMS2 strain to produce ADD and 9OH-AD for industrial application.

10.
Cell Death Differ ; 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33024274

RESUMO

Development of renal fibrosis is a hallmark of renal aging and chronic kidney disease of all etiologies and characterized by extensive renal cell injuries and subsequent myofibroblast transdifferentiations (MTDs), which are significantly influenced by aberrant histone deacetylase (HDAC) activities. However, the key HDAC isoforms and effectors that are causally involved in the processes remain poorly understood. Here, we report that aberrant HDAC3 induction and its inhibition of Klotho, a renal epithelium-enriched aging suppressor, contribute significantly to renal fibrogenesis. HDAC3 was preferentially elevated with concomitant Klotho suppression in fibrotic kidneys incurred by unilateral ureter obstruction (UUO) and aristolochic acid nephropathy (AAN), whereas Hdac3 knockout resisted the fibrotic pathologies. The HDAC3 elevation is substantially blocked by the inhibitors of TGFß receptor and Smad3 phosphorylation, suggesting that TGFß/Smad signal activates Hdac3 transcription. Consistently, an HDAC3-selective inhibitor RGFP966 derepressed Klotho and mitigated the renal fibrotic injuries in both UUO and AAN mice. Further, HDAC3 overexpression or inhibition in renal epithelia inversely affected Klotho abundances and HDAC3 was inducibly associated with transcription regulators NCoR and NF-kB and bound to Klotho promoter in fibrotic kidney, supporting that aberrant HDAC3 targets and transcriptionally inhibits Klotho under renal fibrotic conditions. More importantly, the antirenal fibrosis effects of RGFP966 were largely compromised in mice with siRNA-mediated Klotho knockdown. Hence, HDAC3 aberration and the subsequent Klotho suppression constitute an important regulatory loop that promotes MTD and renal fibrosis and uses of HDAC3-selective inhibitors are potentially effective in treating renal fibrotic disorders.

11.
Nucleic Acids Res ; 48(19): 11185-11198, 2020 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-33021674

RESUMO

Group II introns are the putative progenitors of nuclear spliceosomal introns and use the same two-step splicing pathway. In the cell, the intron RNA forms a ribonucleoprotein (RNP) complex with the intron-encoded protein (IEP), which is essential for splicing. Although structures of spliced group II intron RNAs and RNP complexes have been characterized, structural insights into the splicing process remain enigmatic due to lack of pre-catalytic structural models. Here, we report two cryo-EM structures of endogenously produced group II intron RNPs trapped in their pre-catalytic state. Comparison of the catalytically activated precursor RNP to its previously reported spliced counterpart allowed identification of key structural rearrangements accompanying splicing, including a remodeled active site and engagement of the exons. Importantly, altered RNA-protein interactions were observed upon splicing among the RNP complexes. Furthermore, analysis of the catalytically inert precursor RNP demonstrated the structural impact of the formation of the active site on RNP architecture. Taken together, our results not only fill a gap in understanding the structural basis of IEP-assisted group II intron splicing, but also provide parallels to evolutionarily related spliceosomal splicing.


Assuntos
Íntrons , Processamento de RNA , RNA/metabolismo , Ribonucleoproteínas/química , Éxons , Lactococcus lactis/metabolismo , Conformação de Ácido Nucleico , Ligação Proteica , Conformação Proteica , Spliceossomos/metabolismo
12.
BMC Cancer ; 20(1): 1044, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-33126868

RESUMO

BACKGROUND: The effect of tumor size on account of long-term survival results in perihilar cholangiocarcinoma (PCCA) patients has remained a controversial debate. It is urgent necessary to identify the optimal cutoff value of tumor size in PCCA and integrate tumor size with other prognostic factors into a nomogram to improve the predictive accuracy of prognosis of patients with PCCA. METHODS: Three hundred sixty-three PCCA patients underwent surgical resection were extracted from the Surveillance, Epidemiology and End Results (SEER) database. X-tile program was used to identify the optimal cutoff value of tumor size. A nomogram including tumor size was established to predict 1-, 3- and 5-year cancer-specific survival (CSS) based on the independent risk factors chosen by Kaplan-Meier methods and multivariable cox regression models. The precision of the nomogram for predicting survival was validated internally and externally. RESULTS: PCCA patients underwent surgical resection were classified into 1-19 mm, 20-33 mm and ≥ 34 mm subgroups based on the optimal cutoff for tumor size in terms of CSS. And we noticed that more larger tumor size group had worse tumor grade, advanced T stage, more positive regional lymph nodes and more frequent vascular invasion. The nomogram according to the independent factors was well calibrated and displayed better discrimination power than 7th Tumor-Node-Metastasis (TNM) stage systems. CONCLUSIONS: The results demonstrated that the larger tumor size of PCCA was, the worse survival would be. The proposed nomogram, which outperforms the conventional TNM staging system, showed relatively good performance and could be considered as convenient individualized predictive tool for prognosis of PCCA patients.

13.
Expert Rev Gastroenterol Hepatol ; : 1-10, 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33115276

RESUMO

Objectives: This study aimed to evaluate and update incidence trends of soft-tissue sarcoma (STS) and to develop a nomogram to predict cancer-specific survival (CSS) in patients diagnosed with primary STS of the liver. Methods: Patients with hepatic STS were extracted from the Surveillance, Epidemiology, and End Results (SEER) database. Joinpoint regression analyses were performed to assess the incidence trends of STS. A nomogram was developed based on the independent risk factors chosen by Cox regression models. The calibration curve, area under the receiver operating characteristic curve (AUC), C-index, and decision curve analysis (DCA) were used to assess the predictive performance of the nomogram. Results: The incidence of STS increased between 1994 and 2012. There was a sudden decline in the incidence of STS from 2013. The incidence of STS was different in distinct races and genders. The nomogram for predicting the CSS of hepatic STS according to the independent factors was well calibrated and it displayed optimal discrimination power. Conclusion: This study highlights that age, sex, tumor size, quality of surgery, and histologic subtypes may contribute to the prognosis of hepatic STS, and STS may be etiologically distinct and should be considered separately in different races and genders.

15.
Artigo em Inglês | MEDLINE | ID: mdl-32938156

RESUMO

Chronic refractory wounds are generally caused by local tissue defects and necrosis, and they are clinically characterized by difficult wound healing as well as high recurrence, which seriously affects the life quality of patients. However, specific medicine or acceptable therapeutics to treat these wounds are currently unavailable. Therapy primarily aims to accelerate generation of granulation tissue and decrease recurrence of wounds. The pathogenesis of chronic refractory wounds is closely related to multiple complex signaling pathways and a series of cytokines. Among these signaling pathways, the TGF-ß/Smad7 axis plays a critical role in the course of this disease. Specifically, Smad7 is an antagonist of TGF-ß that can inhibit activation of TGF-ß. Moreover, Smad7 helps to promote wound healing by regulating related cytokines and controlling growth, differentiation and apoptosis of cells, which may be exploited to prevent and treat the disease. This review aims to reveal and evaluate the exact functions and mechanisms of Smad7 in regulation of wound healing.

16.
Clin Neurol Neurosurg ; 197: 106169, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32905977

RESUMO

OBJECTIVES: The treatment safety and efficiency as well as the life quality of patients are still main concerns in gamma knife radiosurgery. In this study, the feasibility of applying diffusion tensor imaging (DTI) in gamma knife radiosurgery for the treatment of brain tumor in motor function areas was investigated, which aims to provide protection on the pyramidal tract and preserve the motor function in patients. PATIENTS AND METHODS: Total 74 patients with solid brain tumor were enrolled and divided into DTI group and control group. The tumor control rate was assessed at 3 months after surgery. The muscle strength of affected limb, KPS scores, ZEW scores and complications were evaluated at 3 and 6 months after gamma knife radiosurgery. RESULTS: Our results indicated that the tumor control rate, complication rate, the muscle strength of affected limb and KPS scores were not significantly different between the two groups at 3 months after surgery. At 6 months after gamma knife radiosurgery, the complication rate (0% vs 50 %, P = 0.044), KPS scores (64.9 % vs 37.8 %, P = 0.036) and ZEW scores (78.4 % vs 54.1 %, P = 0.044) of DTI group were better than the control group. Furthermore, the stability of muscle strength in patients with limb dysfunction was significantly improved in DTI group (86.4 % vs 50 %, P = 0.028). CONCLUSION: In summary, the application of DTI in gamma knife radiosurgery for the treatment of brain tumors in motor function areas can precisely define the tumor edge from pyramidal tract, which will support on designing individual treatment plan, reducing the incidence of complications, and improving long-term life quality in patients.

17.
J Clin Lab Anal ; : e23598, 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-32989838

RESUMO

OBJECTIVE: This study aims to investigate blood and biochemical laboratory findings in patients with coronavirus disease (COVID-19) and analyze the potential predictors of poor outcome in patients with COVID-19. METHODS: The clinical, laboratory, and outcome data of 87 patients with COVID-19 were collected and retrospectively analyzed. Only data collected at the time of admission were used in the analysis for predictors of poor outcome. These patients were divided into two groups: the adverse prognosis group (36 patients) and the non-adverse prognosis group (51 patients). The adverse prognosis of COVID-19 patients was defined as admission to the intensive care unit or death. RESULTS: On the univariate analysis, age, white blood cell (WBC) count, neutrophil counts, lymphocytes count, neutrophils-to-lymphocytes ratio (NLR), interleukin-6, albumin-to-globulin ratio (AGR), albumin, lactate dehydrogenase, glutamyl transpeptidase, and blood glucose were found to be the significant predictors. On the multivariate analysis, the predictors of poor outcome of patients with COVID-19 were NLR (OR = 2.741, [95% CI = 1.02 ~ 7.35], P = .045) and IL-6 (OR = 1.405, [95% CI = 1.04 ~ 1.89, P = .025]). The receiver operating characteristic (ROC) curve revealed that the AUC of NLR, interleukin-6, pneumonia severity index (PSI) score, and Confusion-Urea-Respiratory Rate-Blood pressure-65 (CURB-65) score were 0.883, 0.852, 0.824, and 0.782, respectively. CONCLUSION: High interleukin-6 (6 pg/mL, cuff value) and NLR (4.48, cuff value) can be used to predict poor outcomes in patients with COVID-19 on admission, thus can serve as a beneficial tool for timely identifying COVID-19 patients prone to poor outcome and reduce patient mortality through early intervention.

18.
J Am Chem Soc ; 142(41): 17557-17563, 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-32954726

RESUMO

When the size of nanomaterials reduces to the sub-1 nm scale, benefiting from size-induced mechanical flexibility and nearly 100% exposure of surface atoms, some new physical and chemical phenomena emerge, such as flexibility and polymer-like rheology. However, how to design and synthesize superflexible and high-performance hybrid sub-1 nm superstructures remains a great challenge. Herein, by incorporating four kinds of tungsten-based polyoxometallate (POM) clusters into the synthetic system of MoO3 during the nucleation step, we successfully prepared four kinds of super-flexible hybrid sub-1 nm nanobelt superstructures (HSNSs). Molecular dynamics (MD) simulations demonstrated that POM clusters interacted with MoO3 molecules and co-assembled into stable HSNSs, which could shrink, bend, curl and twist randomly in space and show super-flexible properties. These four kinds of MoO3-POM HSNSs not only performed high photothermal conversion but also showed excellent catalytic activity in the oxidation of thioethers at room temperature. This work paves the way for synthesis and broader applications of super-flexible cluster-inorganic-materials-based HSNSs.

19.
Neurochem Res ; 45(11): 2723-2731, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32902742

RESUMO

Blast-induced traumatic brain injury (bTBI) is a leading cause of disability and mortality in soldiers during the conflicts in Iraq and Afghanistan. Although substantial clinical and animal studies have investigated the pathophysiology and treatments of bTBI, few effective therapies have been found, especially for the early rescue in the battlefield. The aim of this study is to evaluate neuroprotective effects of early normobaric hyperoxia (NBO) on bTBI. We established a rat model of bTBI caused by explosion in the cabin. It exhibited typical changes of mild bTBI, like impaired neurological function, brain edema, minor intracranial hemorrhage and neuron necrosis. The rats were divided into 4 groups (n = 12): Sham, Vehicle, hyperbaric oxygen (HBO) and NBO. Neurological function of the rats was assessed by the Neurological Severity Scores (NSS) at 24 h and 72 h after explosion. Serum interleukin-6 (IL-6), neuron specific enolase (NSE) and tau protein were measured at 24 h and 72 h after explosion. Brain water content was measured and Aquaporin-4 (AQP4) immunostaining was performed. Neuronal apoptosis was analyzed by TUNEL staining. NBO demonstrated curative effects on protecting the neurological function. Serum levels of NSE and tau protein were reduced at 24 h and 72 h after explosion. But the levels of IL-6 were not reduced significantly at both time points. Cerebral edema was alleviated. Simultaneously, AQP4 immunostaining of the hippocampus showed remarkably decreased expression after treatment. The number of apoptotic cells in hippocampus was also decreased. Compared with HBO, NBO is simple and convenient, and can be administered in remote areas. It may be a promising therapy for early rescue of bTBI in the battlefield.

20.
Dalton Trans ; 49(32): 11163-11169, 2020 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-32747881

RESUMO

The cyclometalated Pt(ii) acetylide derivative with a 1,3-bis(N-octyl-benzimidazol-2-yl)benzene (N^C^N) ligand and a free terpyridine (TPY) receptor has been successfully synthesized and characterized. X-ray crystallography shows its inefficient conjugation degree between the [(N^C^N)Pt] and TPY planes. This bifunctional complex shows an enhanced 1MLCT/LLCT absorption band (ε = 3.30 × 104 dm3 mol-1 cm-1) centered at λmax = 365 nm, and the well-resolved vibronic-structured 3MLCT/LLCT emission bands (Φ = 0.08, τ = 3.43 µs) in the range of ca. 475-700 nm. Consecutive titrations show that added Zn2+ and Eu(HFA)3 bond to its free TPY receptor with 1 : 2 and 1 : 1 stoichiometry to form the heterotrinuclear Pt-Zn-Pt (Ka = 3.48 × 104 mol-1 dm3) and heterodinuclear Pt-Eu (Ka = 1.73 × 104 mol-1 dm3) complexes, respectively. A sensitizing effect of Zn2+ on the TPY unit, and the incomplete d → f energy transfer from the [(N^C^N)Pt(ii)] antenna donor to the Eu(iii) center with maximum efficiency of 51.8% are observed. Using an in situ mixed titration strategy, the R/G/B emission triads consisted of red [(TPY)Eu(HFA)3] and green [(N^C^N)Pt(ii)] dual phosphorescence and blue [(TPY)Zn(TPY)] fluorescence, which can be well balanced to realize the white-light-emission with CIE coordinates (x = 0.36, y = 0.36) by precisely controlling the molar ratio (9 : 1 : 2) of the parent complexes, Eu(HFA)3 and Zn(ClO4)2.

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