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1.
Inorg Chem ; 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33826306

RESUMO

The determination of active sites in metal nanoclusters is of great significance for the in-depth understanding of the structural evolution and the mechanism of physicochemical properties. In this work, the surface active Ag2(SR)3 units of the Ag48Cl14(S-Adm)30 nanocluster are determined, and the active-site tailoring of this nanocluster gives rise to two derivative nanoclusters, i.e., the structure-maintained Ag48Cl14(S-Adm)26(S-c-C6H11)4 and the structure-growth Ag50Cl16(S-Adm)28(DPPP)2. Both Ag48 and Ag50 nanoclusters exhibit almost the same cluster framework, but the Ag2(S-Adm)3 active units are regulated to Ag3(S-Adm)2(DPPP)1Cl1 with the transformation from Ag48 to Ag50. The surface active sites on Ag48 are rationalized by analyzing its crystal structure and the ligand-exchange-induced cluster transformation. This study provides some inspiration toward the active-site tailoring of nanocluster surface structures, which is significant for the preparation of new cluster-based nanomaterials with customized structures and enhanced performance.

2.
Disabil Rehabil ; : 1-6, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33826431

RESUMO

PURPOSE: Patients who adhere to their disease-modifying therapies (DMTs) have a lower rate of MS-related relapses and disability. We sought to determine the adherence rate to DMTs and the association between adherence to DMTs and employment in patients with multiple sclerosis (MS). METHOD: One hundred and forty-two patients with MS who were periodically followed in our clinic between January 2000 and January 2020. We compared three groups of patients, defined according to their adherence to DMTs (non-adherent; poorly adherent; adherent), on their obtaining paid employment. RESULTS: Forty-seven MS patients (33.1%) were non-adherent to any DMT medication, while 88 MS patients (62.0%) demonstrated good and 7 (4.9%) poor adherences. More patients in the good-adherence group were in paid employment 42.0% compared to 23.4% in the non-adherent group (p = 0.587) after controlling for potential co-founders. CONCLUSION: In this study veterans who adhered to their DMTs were 2.4 times more likely to be in paid-employment compared to non- or poorly-adherent patients. The clinical significance of this study is to encourage MS patients to adhere to their DMTs as a motivating factor of being in paid-employment.Implications for rehabilitationWhat is known about this subject? In the setting of a randomized controlled trial adherence rates reported for different injectable DMTs vary from 79-85% for once a week interferon beta-1a (IM IFNb-1a) to 49-78% for other injectable DMTs.•What are the new findings and/or impact on clinical practice?•Paid employment was more common among veterans whose adherence to DMTs was good (42.0% employed) or poor (42.9%) than among those who were non-adherent (23.4%). Veterans who adhered to DMTs were also younger, had less severe MS, and displayed less cognitive and physically impairment than those who did not adhere.•Being employed can act as a motivating factor to encourage adherence to treatment aimed at preventing accumulation of mental and physical disabilities.

3.
J Immunother Cancer ; 9(4)2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33820821

RESUMO

Multiple primary lung cancer (MPLC) remains a tough challenge to diagnose and treat. Although neoadjuvant immunotherapy has shown promising results in early stage non-small cell lung cancer, whether such modality can benefit all primary lesions remains unclear. Herein, we performed integrated multiomics analysis in one patient with early stage MPLC with remarkable tumor shrinkage in a solid nodule and no response in two subsolid nodules after treatment with three cycles of neoadjuvant pembrolizumab. Genomic heterogeneity was observed among responding nodules with high levels of infiltrating CD8+ and CD68+ immune cells. Substantially downregulated human leukocyte antigen (HLA)-related genes and impaired T lymphocyte function were observed in non-responding nodules. A larger proportion of infiltrating tissue resident memory T cells (Trm) along with high T cell receptor repertoire clonality in responding nodules were validated as predictive and prognostic biomarkers in multiple cancer types using external public datasets. These results suggested that neoadjuvant programmed death 1 (PD-1)/programmed death ligand 1 inhibitors alone may not be an optimal therapeutic strategy for MPLC due to disparities in genomic alterations and immune microenvironment among different lesions. Additionally, we postulate that increased infiltration of Trm may be a unique marker of early immune responses to PD-1 blockade.

4.
Inorg Chem ; 2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33769038

RESUMO

The extraction and complexation of trivalent americium (Am) and lanthanides (Ln) by four 2,9-diamide-1,10-phenanthroline (DAPhen) ligands with different alkyl substituent groups on the diamide moiety in an ionic liquid (IL), C4mimNTf2, were studied through a combination of batch extraction, spectroscopic, and calorimetric approaches. All four DAPhen ligands can achieve selective separation of Am(III) from Eu(III), but the detailed extractability and the extraction kinetics are affected significantly by the length of the alkyl substituent groups. UV-vis absorption spectrophotometric titrations indicate that Ln(III) coordinates with all four ligands in a 1:2 mode in the ionic liquid and the binding strength decreases with the increase of the alkyl chain length. The complexation of the DAPhen ligands with Ln(III) in the ionic liquid is driven by highly positive entropies and opposed by endothermic enthalpies. A luminescence spectroscopy study suggests that each DAPhen ligand coordinates in a tetradentate form with Eu(III). This work further unravels the unique extraction and coordination behavior in an ionic liquid system and offers additional guidelines to design more efficient DAPhen ligands for Ln(III)/An(III) separation.

5.
Biochem Biophys Res Commun ; 553: 187-190, 2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33774220

RESUMO

PIWI family proteins are important members of Argonaute family that play an essential role in spermatogenesis and development when loaded with piRNAs. Here we solved the crystal structure of the human PIWIL2 PAZ domain and found its PAZ domain adopts a canonical PAZ fold. We furhter built a homology model of PIWIL2 bound to 2 nt 3' overhangs. We found that PIWIL2 utilizes a deep hydrophobic concave to accommodate the 2 nt at 3'-end of RNAs. The recognition of 2 nt 3' overhangs by PIWIL2 is conserved in other human PIWIL proteins, implicating the evolutionarily conserved role of PAZ domain in binding to target RNAs.

6.
Br J Nutr ; : 1-38, 2021 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-33749571

RESUMO

A 12-week experiment was conducted to evaluate the influences of thiamine on growth performance and intestinal mitochondrial biogenesis and function of M. amblycephala fed a high-carbohydrate (HC) diet. Fish (24.73 ± 0.45 g) were randomly assigned one of four diets; two carbohydrate levels (30 and 45%) and two thiamine levels (0 and 1.5 mg kg-1). HC diets significantly decreased DGC, GRMBW, FIMBW, intestinal activities of amylase, lipase, Na+, K+-ATPase, CK, complex I, III and IV, intestinal microvilli length, number of mitochondrial per field, ΔΨm, the P-AMPK/T-AMPK ratio, PGC-1ß protein expression as well as the transcriptions of AMPKα1, AMPKα2, PGC-1ß, TFAM, Opa-1, ND-1 and COX-1 and 2, while the opposite was true for ATP, AMP and ROS, and the transcriptions of Drp-1, Fis-1 and Mff. Dietary thiamine concentrations significantly increased DGC, GRMBW, intestinal activities of amylase, Na+, K+-ATPase, CK, complex I and IV, intestinal microvilli length, number of mitochondrial per field, ΔΨm, the P-AMPK/T-AMPK ratio, PGC-1ß protein expression as well as the transcriptions of AMPKα1, AMPKα2, PGC-1ß, Opa-1, ND-1, COX-1 and 2, SGLT-1 and GLUT-2. Furthermore, a significant interaction between dietary carbohydrate and thiamine was observed in DGC, GRMBW, intestinal activities of amylase, CK, complex I and IV, ΔΨm, the AMP/ATP ratio, the P-AMPK/T-AMPK ratio, PGC-1ß protein expression as well as the transcriptions of AMPKα1, AMPKα2, PGC-1ß, Opa-1, COX-1 and 2, SGLT-1 and GLUT-2. Overall, thiamine supplementation improved growth performance, and intestinal mitochondrial biogenesis and function of M. amblycephala fed HC diets.

7.
Chin J Traumatol ; 2021 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-33678536

RESUMO

PURPOSE: This meta-analysis compared the clinical outcome of three-dimensional (3D) printing combined with open reduction and internal fixation (ORIF) to traditional ORIF in the treatment of acetabular fractures. METHODS: We searched the Cochrane Library, PubMed, Embase, VIP database, CNKI, and Wanfang database with keywords "acetabular fracture", "3D printing", "three-dimensional printing", "open reduction and internal fixation", "Acetabulum", "Acetabula" from January 2000 to March 2020. Two reviewers independently selected articles, extracted data, assessed the quality evidence and risk bias of included trials using the Cochrane Collaboration' s tools and/or Newcastle-Ottawa scale. When the two analysts had different opinions, they would ask the third analyst for their opinion. Randomized controlled trials or retrospective comparative studies of 3D printing combined with ORIF (3D printing group) versus traditional ORIF (conventional group) in the treatment of acetabular fractures were selected. The data of operation time, intraoperative blood loss, intraoperative fluoroscopy times, incidence of complications, excellent and good rate of Matta score for reduction, and excellent and good rate of hip function score were extracted. Stata14.0 statistical software was used for analysis. RESULTS: Altogether 9 articles were selected, including 5 randomized controlled trials and 4 retrospective studies. In total of 467 patients, 250 in the conventional group, and 217 in the 3D printing group. The operation time in the 3D printing group was less than that in the conventional group and the difference was statistically significant (standardized mean difference (SMD) = -1.19, 95% CI: -1.55 to -0.82, p < 0.05). The intraoperative bleeding volume of the 3D printing group was significantly lower than that of the conventional group (SMD = -1.08, 95% CI: -1.65 to -0.51, p < 0.05). The fluoroscopy times were less in the 3D printing group than in the conventional group and the difference was statistically significant (SMD = -1.64, 95% CI: -2.35 to -0.93, p < 0.05). The total incidence of complications in the 3D printing group was significantly lower than that in the conventional group (OR = 0.43, 95% CI: 0.24-0.79, p < 0.05). There was no significant difference in the excellent and good rate of Matta score for reduction between the two groups (OR = 0.60, 95% CI: 0.34-1.06, p > 0.05). There was no significant difference in the excellent and good rate of hip function score at the end of postoperative follow-up between the two groups (OR = 0.84, 95% CI: 0.46-1.56, p > 0.05), but the follow-up time varies from 6 months to 40 months. CONCLUSION: Compared with traditional ORIF, 3D printing combined with ORIF has certain advantages in terms that 3D printing not only helps surgeons to understand acetabular fractures more intuitively, but also effectively reduces operation time, intraoperative blood loss, intraoperative fluoroscopy times, and postoperative complications. However, there were no significant difference in the excellent and good rate of Matta score for reduction and the excellent and good rate of hip function score at the end of follow-up.

8.
Chemosphere ; 271: 129828, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33736216

RESUMO

Previous studies suggest arsenic exposure may increase the risk of gestational diabetes mellitus (GDM). However, prior assessments of total arsenic concentrations have not distinguished between toxic and nontoxic species. Our study aimed to investigate the relationships between inorganic arsenic exposure, arsenic methylation capacity, and GDM. Sixty-four cases of GDM and 237 controls were analyzed for urinary concentrations of inorganic arsenic species and their metabolites (arsenite (As3), arsenate (As5), monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA)), and organic forms of arsenic. Inorganic arsenic exposure was defined as the sum of inorganic and methylated arsenic species (iSumAs). Methylation capacity indices were calculated as the percentage of inorganic arsenic species [iAs% = (As3 + As5)/iSumAs, MMA% = MMA/iSumAs, and DMA% = DMA/iSumAs]. Multivariable logistic regression was performed to evaluate the association between inorganic arsenic exposure, methylation capacity indices, and GDM. We did not observe evidence of a positive association between iSumAs and GDM. However, women with GDM had an increased odds of inefficient methylation capacity when comparing the highest and lowest tertiles of iAs% (adjusted odds ratio (aOR) = 1.48, 95% CI 0.58-3.77) and MMA% (aOR = 1.95 (95% CI 0.81-4.70) and a reduced odds of efficient methylation capacity as indicated by DMA% (aOR = 0.62 (95% CI 0.25-1.52), though the confidence intervals included the null value. While the observed associations with arsenic methylation indices were imprecise and warrant cautious interpretation, the direction and magnitude of the relative measures reflected a pattern of lower detoxification of inorganic arsenic exposures among women with GDM.


Assuntos
Arsênico , Arsenicais , Diabetes Gestacional , Ácido Cacodílico , Estudos de Casos e Controles , Diabetes Gestacional/induzido quimicamente , Feminino , Humanos , Metilação , Gravidez
9.
Appl Opt ; 60(3): 763-772, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33690451

RESUMO

This paper presents a real-time measurement method for the skin temperature of the human arm. In this method, the air temperature close to the arm skin is measured via large lateral shearing interferometry, thus avoiding the possible influences of the different physical characteristics of different people, while maintaining the advantages of optical measurement, including its noncontact, noninvasive, and rapid features. The method captures the real-time fringe patterns generated using a parallel-sided plate when a collimated laser light beam transfers through the air surrounding the arm to be measured. Additionally, the phase difference distribution caused by the temperature difference is calculated in combination with the background fringe patterns. The phase difference in the light close to the arm skin is then estimated via a linear fitting method. Accordingly, based on the size parameters of the arm cross section and the ambient temperature monitored in real time, the air temperature close to the arm skin, which is considered equal to the arm skin temperature, is determined while considering the heat conduction effect. Experimental measurements of the temperature of human arm skin were conducted using the proposed method, and the axillary temperatures of the same person before and after the experiments were also measured using an electronic thermometer and a mercury thermometer. Good agreements were found, verifying the reliability of the proposed method. Moreover, based on this method, the possibility for the construction of a real-time body temperature measurement system is also discussed.

10.
Zhongguo Zhong Yao Za Zhi ; 46(2): 359-365, 2021 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-33645122

RESUMO

To compare the effect of hot or warm property of Chinese medicine(CM) on the skin toxicity of essential oils(EOs) as penetration enhancer in vitro and in vivo, and explore the mechanism. EOs were extracted from WIM of Bichengqie(Litseae Fructus), Dingxiang(Flos Syzygii Aromatici), Huajiao(Pericarpium Zanthoxyli Bungeani), and Xiaohuixiang(Fructus Foeniculi) with warm property, and Ganjiang(Rhizoma Zingiberis), Gaoliangjiang(Rhizoma Alpiniae Officinari), Hujiao(Fructus Piperis), and Wuzhuyu(Fructus Evodiae Rutaecarpae) with hot property, respectively. Then the in vitro toxicity was evaluated by human keratinocyte cytotoxicity. In vivo skin irritation potency was also evaluated through pathological observation after topical administration. The components, especially those located in stratum corneum, were analyzed by GC-MS. The main components, namely monoterpenes and sesquiterpenes, of EOs extracted from CM with hot property,were detected for the interaction with keratino-lipid ceramide 3 by molecular simulation technology; and the interaction energy value was calculated based on the optimal conformation. It was found that the skin cell toxicity of EOs from CM with hot property was significantly higher than that of EOs from CM with warm property. However, there was no significant difference between them by in vivo skin irritation evaluation. Whether from CM with hot property or warm property, EOs showed a significant reduced toxicity compared with azone. Sesquiterpenes(33.56%±19.38%) were found to be one of the main components in EOs from CM with hot property, while almost no sesquiterpenes was found in EOs from CM with warm property. After topical administration of EOs from CM with hot property, sesquiterpenes were demonstrated to be prone to locate in stratum corneum. The results of molecular simulation also revealed that the interaction between sesquiterpenes and ceramide 3 was significantly stronger than that of monoterpenes(P<0.01). In conclusion, the location of sesquiterpenes in stratum corneum resulted in the significant difference between in vitro skin cell toxicity and in vivo skin irritation potency. The EOs from CM with hot property shall be taken into account for further development of potent penetration enhancer.


Assuntos
Óleos Voláteis , Sesquiterpenos , Humanos , Monoterpenos/metabolismo , Óleos Voláteis/metabolismo , Óleos Voláteis/toxicidade , Sesquiterpenos/metabolismo , Pele/metabolismo , Absorção Cutânea
11.
Curr Microbiol ; 78(4): 1628-1635, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33686506

RESUMO

The microorganisms inhabiting the gastrointestinal tract play important roles in many host physiological processes, including the absorption and metabolism of nutrients and immune function. The Amur tiger (Panthera tigris altaica) is listed by the International Union for the Conservation of Nature (IUCN) as a threatened species. Efforts are underway to breed Amur tigers under artificial settings to preserve this rare species. To maximize the imitation of the diet that this species consumes in the wild, the diet in the present study was composed of a variety of raw meats and was administered with regular fasting. In view of the important roles that the microbiota play in the host, in the present study, the microbiota of Amur tigers at three different ages were investigated. The results showed that the microbial diversity and richness decreased with age. Principal coordinate analysis showed significant differences among the three age groups. Linear discriminant analysis (LDA) of effect size (LEfSe) demonstrated the enrichment of the genus unclassified_f__Ruminococcaceae, genus Coprococcus_1, genus Ruminococcus__gauvreauii_group, family unclassified_o__Clostridiales and genus unclassified_o__Clostridiales in the JB group (1- year old) and the enrichment of the genus Catenisphaera in the AB group (over 4-year old). The results of the present study demonstrated the adaptation of the microbiota in captive Amur tigers to a diet similar to the one they consume in the wild. Furthermore, these results may reflect the microbiota of wild Amur tigers to a certain extent.

12.
EBioMedicine ; 65: 103271, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33714027

RESUMO

BACKGROUND: N6-methyladenosine (m6A) is the most abundant mRNA modification. Whether m6A regulators can determine tumor aggressiveness and risk of immune evasion in pancreatic ductal adenocarcinoma (PDAC) remains unknown. METHODS: An integrated model named "m6Ascore" is constructed based on RNA-seq data of m6A regulators in PDAC. Association of m6Ascore and overall survival is validated across several different datasets. Overlaps of m6Ascore and established molecular classifications of PDAC is examined. Immune infiltration, enriched pathways, somatic copy number alterations (SCNAs), mutation profiles and response to immune checkpoint inhibitors are compared between m6Ascore-high and m6Ascore-low tumors. FINDINGS: m6Ascore is associated with dismal overall survival and increased tumor recurrence in PDAC as well as several other solid tumors including colorectal cancer and breast cancer. Basal-like (Squamous) PDAC has higher m6Ascore than that in the classical PDAC. Mechanism study showed m6Ascore-high tumors are characterized with reduced immune infiltration and T cells exhaustion. Meanwhile, m6Ascore is associated with genes regulating cachexia and chemoresistance in PDAC. Furthermore, distinct SCNAs patterns and mutation profiles of KRAS and TP53 are present in m6Ascore-high tumors, indicating immune evasion. m6Ascore-low tumors have higher response rates to immune checkpoint inhibitors (ICIs). INTERPRETATION: These findings indicate m6Ascore can predict aggressiveness and immune evasion in pancreatic cancer. This model has implications for pancreatic cancer prognosis and treatment response to ICIs. FUNDING: This work was supported in part by National Institutes of Health (NIH) grants to M. Li (R01 CA186338, R01 CA203108, R01 CA247234 and the William and Ella Owens Medical Research Foundation) and NIH/National Cancer Institute Q39 award P30CA225520 to Stephenson Cancer Center.

13.
Mol Genet Genomic Med ; : e1668, 2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33764685

RESUMO

BACKGROUND: Schmid-type metaphyseal chondrodysplasia (SMCD) is a rare autosomal dominant skeletal dysplasia caused by heterozygous mutations in COL10A1, the gene which encodes collagen type X alpha 1 chain. However, its genotype-phenotype relationship has not been fully determined. Subjects and Methods The proband is a 2-year-old boy, born of non-consanguineous Chinese parents. We conducted a systematic analysis of the clinical and radiological characteristics and a follow-up study of the proband. Whole-exome sequencing was applied for the genetic analysis, together with bioinformatic analysis of predicted consequences of the identified variant. A homotrimer model was built to visualize the affected region and predict possible outcomes of this variant. Furthermore, a literature review and genotype-phenotype analysis were performed by online searching all cases with SMCD. RESULTS: A novel heterozygous variant (NM_000493.4: c.1863_1866delAATG, NP_000484.2: p.(Met622 Thrfs*54)) was identified in COL10A1 gene in the affected child. And it was predicted to be pathogenic by in silico analysis. Protein modeling revealed that the variant was located in the NC1 domain, which was predicted to produce truncated collagen and impair the trimerization of collagen type X alpha 1 chain and combination with molecules in the matrix. Moreover, genotype-phenotype correlation analysis demonstrated that patients with truncating variants or variants in NC1 domain often presented earlier onset and severer symptoms compared with those with non-truncating or variants in non-NC1 domains. CONCLUSION: The NC1 domain of COL10A1 was proved to be the hotspot region underlying SMCD, patients with variants in NC1 domain were more likely to present severer manifestations at an earlier age.

14.
Ecotoxicol Environ Saf ; 214: 112019, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33639494

RESUMO

Cd is a common pollutant that contaminates the ecological environment of soil-crop systems and threatens food security and human health. Sorghum (Sorghum bicolor (L.) Moench) has a great potential for use as energy feedstock and Cd phytoremediation. Therefore, the identification of sorghum genotypes with high Cd accumulation is of great significance to Cd pollution remediation and production of bioenergy. A total of 126 biomass sorghum genotypes grown in a Cd-polluted field were investigated, and their agronomic traits were analyzed, including plant height, leaf number, shoot dry weight (SDW), soil and plant analyzer development (SPAD) value, and concentration of metal ions at seedling stage. Plant height was an important factor for screening potential biomass sorghum species because it presented a significant correlation with the Cd concentration in shoots and SDW (P < 0.01). The highest and lowest Cd concentration in sorghum shoots were 7.88 and 0.99 mg kg-1, respectively. The Cd concentration presented a negative and significant correlation with Mn in sorghum shoots (r = -0.303, P < 0.01), which was in agreement with the results that sorghum species with high Cd concentrations have lower Mn concentrations. In the mature stage, sorghum 12530 presented higher Cd concentration and dry weight in shoots compared with other genotypes. In summary, plant height, SDW, and concentration of Mn in sorghum shoots are critical parameters that synthetically influence the accumulation of Cd in sorghum shoots.


Assuntos
Cádmio/metabolismo , Poluentes do Solo/metabolismo , Biodegradação Ambiental , Biomassa , Cádmio/análise , Grão Comestível/química , Recuperação e Remediação Ambiental , Genótipo , Humanos , Fenótipo , Desenvolvimento Vegetal , Folhas de Planta/química , Plântula/química , Solo , Poluentes do Solo/análise , Sorghum/crescimento & desenvolvimento
15.
Phys Chem Chem Phys ; 23(9): 5236-5243, 2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33629668

RESUMO

Global switching on-the-fly trajectory surface hopping molecular dynamics simulation was performed on the accurate TD-B3LYP/6-31G* potential energy surfaces for E-to-Z and Z-to-E photoisomerization of dMe-OMe-NAIP up to S1(ππ*) excitation. The present TD(DFT) simulation provides accurate calculation for conical intersections between the first-excited and ground states. Thus, simulated quantum yield and lifetime of 0.23 and 620 fs (0.15 and 600 fs) for E-to-Z (Z-to-E) isomerization are in good (relatively good) agreement with experimental observation of 0.25 and 480 fs (0.24 and 430 fs), respectively. Simulated results reveal that photoisomerization pathways are initially uphill to conical intersection zones on the S1 potential energy surface and then downhill to product zones. Three types of representative conical intersections are found for determining photoisomerization mechanisms: one is the rotation type responsible for reactive isomerization and the other two are close to E and Z configurations, respectively, only for nonreactive isomerization. The present conclusions can be held in general for similar large NAIP systems of photoinduced isomerization based on E and Z configurations.

16.
J Mol Histol ; 2021 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-33555537

RESUMO

Nogo-A protein consists of two main extracellular domains: Nogo-66 (rat amino acid [aa] 1019-1083) and Nogo-A-Δ20 (extracellular, active 180 amino acid Nogo-A region), which serve as strong inhibitors of axon regeneration in the adult CNS (Central Nervous System). Although receptors S1PR2 and HSPGs have been identified as Nogo-A-Δ20 binding proteins, it remains at present elusive whether other receptors directly interacting with Nogo-A-Δ20 exist, and decrease cell death. On the other hand, the key roles of EphA4 in the regulation of glioblastoma, axon regeneration and NSCs (Neural Stem Cells) proliferation or differentiation are well understood, but little is known the relationship between EphA4 and Nogo-A-Δ20 in NSCs apoptosis. Thus, we aim to determine whether Nogo-A-Δ20 can bind to EphA4 and affect survival of NSCs. Here, we discover that EphA4, belonging to a member of erythropoietin-producing hepatocellular (Eph) receptors family, could be acting as a high affinity ligand for Nogo-A-Δ20. Trans-membrane protein of EphA4 is needed for Nogo-A-Δ20-triggered inhibition of NSCs apoptosis, which are mediated by balancing p38 inactivation and JNK MAPK pathway activation. Finally, we predict at the atomic level that essential residues Lys-205, Ile-190, Pro-194 in Nogo-A-Δ20 and EphA4 residues Gln-390, Asn-425, Pro-426 might play critical roles in Nogo-A-Δ20/EphA4 binding via molecular docking.

17.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(1): 248-252, 2021 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-33554829

RESUMO

OBJECTIVE: To study the impact of anticoagulant to the quality of umbilical cord blood (UCB). METHODS: 6060 cord blood units (CBUs) were classified into five groups, such as 28 ml: (10-29) ml, 28 ml: (30-69) ml, 28 ml: (70-109) ml, 28 ml: (110-150) ml and 28 ml: (>150) ml according to volume ratio of anticoagulant and CBVs. The count of pre-cryopreservation total nucleated cell (pre-TNC), the viability of nucleated cell (VNC), the amount of CFU-GM and the ratio changes of CD34+ were evaluated and analyzed statistically. RESULTS: It was found that pre-TNC increased with the growth of volume of CBUs (r=0.9937) under the certain volume of antico-agulant, and the TNC in the minimum UCB volume group was (2.57±0.89)×108; the VNC grew up with the increasing count viability of volume (r=0.9897), and the average viability of the minimum volume group remained over 95%; the CFU-GM climbed up with the increasing of volume (r=0.9024), and the number of CFV-GM in minimum volume group reached to of 89/×105; CD34+% grew up with the increase of volume of CBUs (r=0.9641), and the ratio was (0.30±0.19)% for the minimum volume group. CONCLUSION: In certain volume of anticoagulant in collection-bag, pre-TNC, VNC, CFU-GM and CD34+% are all dropped with the decrease of CBUs volume , however, all above-mentioned indexes in the minimun random group still meet the requirement for clinical administration.


Assuntos
Criopreservação , Sangue Fetal , Humanos
18.
ACS Nano ; 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33606517

RESUMO

Transition metal oxides for high-temperature lithium-ion batteries have captivated orchestrated efforts for next-generation high-energy-density anodes. However, due to inherent low tap density, poor conductivity, and structural instability, their poor cyclability capacity and rate performance at elevated temperatures hinder further implementation. Oxygen vacancies (Ov) engineered by manipulating the active sites and electrical conductivity is a promising method for superior lithium storage. Herein, hierarchical MnO/Co nanoparticle-embedded N-doped carbon nanotube (CNT)-assembled carbonaceous micropolyhedrons (Ov-MnO/Co NCPs) are constructed by a "4S" self-assembly, self-template, self-adaptive, and self-catalytic metal-organic framework template method with in situ oxygen vacancies introduced. Impressively, the internal nanoparticles with metallic Co and the external N-doped carbonaceous matrix entangled by fluffy self-generated CNTs synchronously constructed hierarchical micro/nano-secondary hybrids, facilitating highly compacted density, staggered conductive network, multidirectional diffusion pathways, and accelerated electrochemical kinetics. Experimental and density functional theory investigations systematically manifested that the Ov alongside the local built-in electric field within the crystal lattice induced the boosted electrical conductivity, additional active sites, and alleviated structural expansion, further achieving the exceptional diffusivity coefficient and pseudocapacitive capacity. Benefiting from the integrated structural and compositional optimization, the Ov-MnO/Co NCPs achieved distinguished "3C" performance with superior ultralong cyclability (a volumetric capacity of 1713.5 mAh cm-3 at 1 A g-1 up to 1000 cycles), good rate capacity (a well-maintained capacity of 670.2 mAh g-1 even at 10 A g-1), and considerable high-temperature capability at 60 °C.

19.
Nanoscale ; 13(7): 3967-3973, 2021 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-33576355

RESUMO

Porous organic frameworks (POFs) with predesigned structures and tunable porosities have been widely studied in adsorption and heterogeneous catalysis. Introducing ionic structure into the framework endows POFs with new functionalities that may extend their applications. Here, we report new applications for a guanidinium-based ionic POF (IPOF-Cl) in palladium scavenging and heterogeneous catalysis. Due to the ionic framework and the porous structure, the IPOF-Cl displays fast adsorption kinetics and high adsorption capacities (up to 754 mg g-1) of Na2PdCl4 in aqueous solutions via a chemisorption (ion exchange) process. Significantly, it shows excellent scavenging activity towards trace amount of [PdCl4]2- in aqueous solution. More importantly, the loaded [PdCl4]2- species on the IPOF substrate are further reduced into ultrafine Pd nanoparticles with size of ∼2-5 nm. The obtained IPOF-Pd(0) nanocomposite containing uniformly distributed Pd nanoparticles and hierarchical porous structure demonstrates high activity in catalyzing a range of Suzuki coupling reactions. This study provides new routes for the development of ionic porous organic materials for applications in metal scavenging and catalysis.

20.
Artigo em Inglês | MEDLINE | ID: mdl-33632707

RESUMO

INTRODUCTION: Although obesity and hyperinsulinemia are closely intercorrelated, their temporal sequence is still uncertain. This study aims to investigate the temporal relationship patterns between obesity measures and hyperinsulinemia in Chinese adults. RESEARCH DESIGN AND METHODS: The longitudinal cohort consisted of 2493 participants (860 males and 1633 female, mean age 56.71 years at follow-up) for whom measurements of obesity and hyperinsulinemia measures were collected twice between 2011 and 2014, with an average follow-up time of 3 years. Cross-lagged panel analysis was used to examine the temporal relationship between obesity measures (body mass index (BMI); waist circumference (WC); hip circumference (HC); waist-to-hip ratio (WHR)) and hyperinsulinemia (insulin, homeostasis model assessment of insulin resistance (HOMA-IR), or homeostasis model assessment of beta cell function (HOMA-%ß)). RESULTS: After the adjustment of age, sex, smoking, drinking and follow-up years, in the BMI-insulin model, the path coefficient (ß2=0.229; p<0.001) of baseline BMI to follow-up insulin was significantly greater than the path coefficient (ß1=0.073; p<0.001) of baseline insulin to follow-up BMI (p<0.001 for ß2>ß1). In the WHR-insulin model, the path coefficient (ß1=0.152; p<0.001) of baseline insulin to follow-up WHR was significantly greater than the path coefficient (ß2=0.077; p<0.001) of baseline WHR to follow-up insulin (p=0.007 for ß1>ß2). In the WC/HC-insulin model, the path coefficients of baseline insulin to follow-up WC or HC (ß1s) were also greater than the path coefficients of baseline WC or HC to follow-up insulin (ß2s), but the difference between ß1s and ß2s were not significant. The similar temporal patterns were founded between obesity measures with HOMA-IR or HOMA-%ß. CONCLUSIONS: These findings indicate that there is a bidirectional relationship between obesity and hyperinsulinemia, and abdominal obesity measures are more sensitive to hyperinsulinemia measures than BMI.

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