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1.
Ticks Tick Borne Dis ; 15(2): 102293, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38086248

RESUMO

Ticks are primary vectors for many tick-borne pathogens (TBPs) and pose a serious threat to veterinary and public health. Information on the presence of TBPs in Chinese Milu deer (Elaphurus davidianus) is limited. In this study, a total of 102 Chinese Milu deer blood samples were examined for Anaplasma spp., Theileria spp., Babesia spp., Rickettsia spp., and Borrelia spp., and three TBPs were identified: Anaplasma phagocytophilum (48; 47.1 %), Candidatus Anaplasma boleense (47; 46.1%), and Theileria capreoli (8; 7.8 %). Genetic and phylogenetic analysis of the 16S rRNA and 18S rRNA confirmed their identity with corresponding TBPs. To our knowledge, this is the first report on Candidatus A. boleense and T. capreoli detection in Chinese Milu deer. A high prevalence of A. phagocytophilum with veterinary and medical significance was identified in endangered Chinese Milu deer, which could act as potential zoonotic reservoirs. The identification of the TBPs in Chinese Milu deer provides useful information for the prevention and control of tick-borne diseases.


Assuntos
Cervos , Rickettsia , Theileria , Doenças Transmitidas por Carrapatos , Carrapatos , Animais , Carrapatos/microbiologia , Cervos/microbiologia , Filogenia , RNA Ribossômico 16S/genética , Rickettsia/genética , Anaplasma/genética , Doenças Transmitidas por Carrapatos/epidemiologia , Doenças Transmitidas por Carrapatos/veterinária , Doenças Transmitidas por Carrapatos/microbiologia , Theileria/genética , China/epidemiologia
2.
Iran J Immunol ; 20(4): 456-465, 2023 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-37865874

RESUMO

Background: Natural killer (NK) cells play a role in the pathogenesis of various metabolic diseases related to obesity. While our initial findings have indicated a potential involvement of NK cells in the pathogenesis of type 2 diabetes mellitus, the precise mechanism underlying NK cell-mediated development of this form of diabetes remains inadequately comprehended. Objective: To investigate the impact and the underlying mechanism of high glucose and elevated levels of free fatty acids (FFAs) on immune and inflammatory responses and oxidative stress in NK92 cells. Methods: In this experiment, the CCK8 cytotoxicity assay was used to select the 44.4 mM and 1.5 mM concentrations of high glucose and high FFAs, respectively, to treat NK92 cells for 4 days. The concentrations of superoxide dismutase (SOD) and glutathione (GSH) were determined using a biochemical analyzer. Intracellular reactive oxygen species (ROS) levels, cytokines concentrations (TNF-α, IFN-γ, IL-6, and IL-10), and the expression levels of intracellular molecules (perforin and granzyme B) were assessed by flow cytometry. Results: The number of NK92 cell clumps was significantly reduced in the high-FFA (HF) group. In addition, the production of ROS and levels of cytokines (TNF-α, IFN-γ, IL-6, and IL-10) significantly decreased in the HF group but showed no significant change in the high-glucose (HG) group. This observation was consistent with the expression levels of perforin and granzyme B that decreased in the HF group. Conclusion: High FFAs induced morphological changes and serious damage to oxidative stress and inflammatory response in NK92 cells.


Assuntos
Diabetes Mellitus Tipo 2 , Fator de Necrose Tumoral alfa , Humanos , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-10/metabolismo , Granzimas/metabolismo , Ácidos Graxos não Esterificados/metabolismo , Interleucina-6/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Perforina/metabolismo , Células Matadoras Naturais , Citocinas/metabolismo , Anti-Inflamatórios/farmacologia , Linhagem Celular , Glucose/metabolismo
3.
Angew Chem Int Ed Engl ; 62(45): e202311480, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37725404

RESUMO

Elaborately designed multifunctional electrocatalysts capable of promoting Li+ and CO2 transport are essential for upgrading the cycling stability and rate capability of Li-CO2 batteries. Hydrogen-bonded organic frameworks (HOFs) with open channels and easily functionalized surfaces hold great potential for applications in efficient cathodes of Li-CO2 batteries. Herein, a robust HOFS (HOF-FJU-1) is introduced for the first time as a co-catalyst in the cathode material of Li-CO2 batteries. HOF-FJU-1 with cyano groups located periodically in the pore can induce homogeneous deposition of discharge products and accommodate volumetric expansion of discharge products during cycling. Besides, HOF-FJU-1 enables effective interaction between Ru0 nanoparticles and cyano groups, thus forming efficient and uniform catalytic sites for CRR/CER. Moreover, HOF-FJU-1 with regularly arranged open channels are beneficial for CO2 and Li+ transport, enabling rapid redox kinetic conversion of CO2 . Therefore, the HOF-based Li-CO2 batteries are capable of stable operation at 400 mA g-1 for 1800 h and maintain a low overpotential of 1.96 V even at high current densities up to 5 A g-1 . This work provides valuable guidance for developing multifunctional HOF-based catalysts to upgrade the longevity and rate capability of Li-CO2 batteries.

4.
Nanomicro Lett ; 15(1): 165, 2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37386313

RESUMO

Lithium-sulfur (Li-S) batteries have received widespread attention, and lean electrolyte Li-S batteries have attracted additional interest because of their higher energy densities. This review systematically analyzes the effect of the electrolyte-to-sulfur (E/S) ratios on battery energy density and the challenges for sulfur reduction reactions (SRR) under lean electrolyte conditions. Accordingly, we review the use of various polar transition metal sulfur hosts as corresponding solutions to facilitate SRR kinetics at low E/S ratios (< 10 µL mg-1), and the strengths and limitations of different transition metal compounds are presented and discussed from a fundamental perspective. Subsequently, three promising strategies for sulfur hosts that act as anchors and catalysts are proposed to boost lean electrolyte Li-S battery performance. Finally, an outlook is provided to guide future research on high energy density Li-S batteries.

5.
Small ; 19(28): e2301685, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37010021

RESUMO

Li-CO2 batteries have attracted considerable attention for their advantages of CO2 fixation and high energy density. However, the sluggish dynamics of CO2 reduction/evolution reactions restrict the practical application of Li-CO2 batteries. Herein, a dual-functional Mo2 N-ZrO2 heterostructure engineering in conductive freestanding carbon nanofibers (Mo2 N-ZrO2 @NCNF) is reported. The integration of Mo2 N-ZrO2 heterostructure in porous carbons provides the opportunity to simultaneously accelerate electron transport, boost CO2 conversion, and stabilize intermediate discharge product Li2 C2 O4 . Benefiting from the synchronous advantages, the Mo2 N-ZrO2 @NCNF catalyst endows the Li-CO2 batteries with excellent cycle stability, good rate capability, and high energy efficiency even under high current densities. The designed cathodes exhibit an ultrahigh energy efficiency of 89.8% and a low charging voltage below 3.3 V with a potential gap of 0.32 V. Remarkably, stable operation over 400 cycles can be achieved even at high current densities of 50 µA cm-2 . This work provides valuable guidance for developing multifunctional heterostructured catalysts to upgrade longevity and energy efficiency of Li-CO2 batteries.

6.
Microb Drug Resist ; 29(7): 274-279, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37074067

RESUMO

Acinetobacter baumannii is a highly antibiotic-resistant pathogen causing nosocomial severe life-threatening infections, especially in critically ill patients. Capsular polysaccharide is a major virulence factor of A. baumannii both in vitro and in vivo. In this study, 220 isolates were collected in the hospital. The prevalent capsular types of A. baumannii were determined using polymerase chain reaction, and the clinical characteristics of infections were analyzed. The virulence of these strains was determined by serum-killing resistance, biofilm formation, and Galleria mellonella survival assays. Twenty-eight isolates (12.7%) carried KL2, and 22 isolates (10%) carried the types KL10, KL14, KL22, and KL52. Compared with non-KL2 (KL10, KL14, KL22, and KL52) isolates, KL2 isolates had significantly higher resistance to all antimicrobials except tigecycline, cefoperazone-sulbactam, or colistin. Seventy-five percent of KL2 A. baumannii and 72.7% of non-KL2 were highly virulent using a G. mellonella model. Biofilm formation was significantly different between the KL2 and non-KL2 groups. The biofilm production of non-KL2 A. baumannii was significantly stronger than that of KL2 A. baumannii. These findings highlight the role of KL2 as a powerful factor for drug resistance and virulence of A. baumannii.


Assuntos
Infecções por Acinetobacter , Acinetobacter baumannii , Humanos , Antibacterianos/farmacologia , Virulência , Infecções por Acinetobacter/tratamento farmacológico , Infecções por Acinetobacter/epidemiologia , Testes de Sensibilidade Microbiana , Resistência a Medicamentos , Farmacorresistência Bacteriana Múltipla/genética
8.
Nanoscale ; 14(40): 15073-15078, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36200835

RESUMO

Rechargeable Li-CO2 batteries are an innovative energy storage technology with broad application prospects owing to their superb energy density and ability to capture the greenhouse gas CO2. However, they are still suffering from severe challenges in the formation and decomposition of electrochemically sluggish Li2CO3 discharge products, resulting in poor battery performance. Development of an efficient cathodic electrocatalyst has the potential to address these issues by catalytically boosting the conversion of Li2CO3. Herein, we have designed a Ru-Cu nanoalloy decorated porous carbon (Ru-Cu@NPC) material derived from an anion-exchanged cationic MOF, and it can serve as an efficient cathode electrocatalyst for Li-CO2 batteries. Benefitting from the uniform distribution of ultrafine Ru-Cu nanoalloys with high catalytic performance, Ru-Cu@NPC displays excellent CO2 reduction and evolution activities. Impressively, the Li-CO2 battery with the Ru-Cu@NPC catalyst exhibits a remarkably low potential gap of 0.93 V at 100 mA g-1 and a stable discharge/charge cycling performance of more than 400 cycles at a high current density of 400 mA g-1 within a limiting capacity of 1000 mA h g-1. The study provides an opportunity for the research of cationic MOF derived bimetallic catalysts in the Li-CO2 battery field.

9.
ACS Appl Mater Interfaces ; 14(40): 45688-45696, 2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36191265

RESUMO

High sulfur loading is essential for achieving high energy density lithium-sulfur (Li-S) batteries. However, serious issues such as low sulfur utilization, poor cycling stability, and sluggish rate performance have been exposed when increasing the sulfur loading for freestanding cathodes. To solve these problems, the adsorption/catalytic ability of high-sulfur-loading cathode toward polysulfides must be improved. Herein, based on excellent properties of cationic MOFs, we proposed that Cu-Mo bimetallic nanoparticles embedded in multifunctional freestanding nitrogen-doped porous carbon nanofibers (Cu-Mo@NPCN) with efficient catalytic sites could be prepared by facile MoO42- anion exchange of cationic MOFs. And, the sulfur embedded in Cu-Mo@NPCN was directly used as self-supporting electrodes, enabling a high areal capacity, good rate performance, and decent cycling stability even under high sulfur loading. The freestanding Cu-Mo@NPCN/10.3S cathode achieves a high volumetric capacity of 1163 mA h cm-3 and a decent areal capacity of 9.3 mA h cm-2 at 0.2 C with a sulfur loading of 10.3 mg cm-2. This work provides an innovative approach for engineering a freestanding sulfur cathode and would forward the development of cationic MOF-derived bimetallic catalysts in various energy storage systems.

10.
JAMA ; 328(8): 728-736, 2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35997729

RESUMO

Importance: Concurrent chemoradiotherapy has been the standard treatment for stage II nasopharyngeal carcinoma (NPC) based on data using 2-dimensional conventional radiotherapy. There is limited evidence for the role of chemotherapy with use of intensity-modulated radiation therapy (IMRT). Objective: To assess whether concurrent chemotherapy can be safely omitted for patients with low-risk stage II/T3N0 NPC treated with IMRT. Design, Setting, and Participants: This multicenter, open-label, randomized, phase 3, noninferiority clinical trial was conducted at 5 Chinese hospitals, including 341 adult patients with low-risk NPC, defined as stage II/T3N0M0 without adverse features (all nodes <3 cm, no level IV/Vb nodes; no extranodal extension; Epstein-Barr virus DNA <4000 copies/mL), with enrollment between November 2015 and August 2020. The final date of follow-up was March 15, 2022. Interventions: Patients were randomly assigned to receive IMRT alone (n = 172) or concurrent chemoradiotherapy (IMRT with cisplatin, 100 mg/m2 every 3 weeks for 3 cycles [n = 169]). Main Outcomes and Measures: The primary end point was 3-year failure-free survival (time from randomization to any disease relapse or death), with a noninferiority margin of 10%. Secondary end points comprised overall survival, locoregional relapse-free survival, distant metastasis-free survival, adverse events, and health-related quality of life (QOL) measured by the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire (QLQ-C30; range, 0-100 points; minimum clinically important difference ≥10 for physical function, symptom control, or health-related QOL; higher score indicates better functioning and global health status or worse symptoms). Results: Among 341 randomized patients (mean [SD] age, 48 [10] years; 30% women), 334 (98.0%) completed the trial. Median follow-up was 46 months (IQR, 34-58). Three-year failure-free survival was 90.5% for the IMRT-alone group vs 91.9% for the concurrent chemoradiotherapy group (difference, -1.4%; 1-sided 95% CI, -7.4% to ∞; P value for noninferiority, <.001). No significant differences were observed between groups in overall survival, locoregional relapse, or distant metastasis. The IMRT-alone group experienced a significantly lower incidence of grade 3 to 4 adverse events (17% vs 46%; difference, -29% [95% CI, -39% to -20%]), including hematologic toxicities (leukopenia, neutropenia) and nonhematologic toxicities (nausea, vomiting, anorexia, weight loss, mucositis). The IMRT-alone group had significantly better QOL scores during radiotherapy including the domains of global health status, social functioning, fatigue, nausea and vomiting, pain, insomnia, appetite loss, and constipation. Conclusions and Relevance: Among patients with low-risk NPC, treatment with IMRT alone resulted in 3-year failure-free survival that was not inferior to concurrent chemoradiotherapy. Trial Registration: ClinicalTrials.gov Identifier: NCT02633202.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Quimiorradioterapia , Cisplatino , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Radioterapia de Intensidade Modulada , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimiorradioterapia/efeitos adversos , Quimiorradioterapia/métodos , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Infecções por Vírus Epstein-Barr/complicações , Feminino , Herpesvirus Humano 4 , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/tratamento farmacológico , Carcinoma Nasofaríngeo/etiologia , Carcinoma Nasofaríngeo/patologia , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/etiologia , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/radioterapia , Qualidade de Vida , Radioterapia de Intensidade Modulada/efeitos adversos , Radioterapia de Intensidade Modulada/métodos
11.
Animals (Basel) ; 12(12)2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35739875

RESUMO

Enterocytozoon bieneusi is the most prevalent microsporidian species that can cause zoonotic diseases in humans and animals. Despite receiving increasing attention in relation to domestic animals, there has been limited information on the infection burden of E. bieneusi in cervids. Altogether, 215 fecal samples collected from four deer species in Beijing, China were examined by nested- Polymerase Chain Reaction (PCR)targeting the internal transcribed spacer (ITS) region. The overall prevalence of E. bieneusi in deer was 21.9% (47/215), with 30.0% (24/80) in Pere David's deer, 27.3% (15/55) in fallow deer, 12.5% (5/40) in sika deer, and 7.5% (3/40) in Chinese water deer. Thirteen E. bieneusi genotypes were identified, including six known (HLJD-V, MWC_d1, BEB6, CGC2, JLD-XV, and HND-I) and seven novel genotypes (BJED-I to BJED-V, BJFD, and BJCWD). A phylogenetic analysis showed that 38.3% of the isolates belonged to zoonotic Group 1. In addition, E. bieneusi infection was first detected in fallow deer and Chinese water deer, which could act as potential zoonotic reservoirs. Our findings suggest that E. bieneusi circulates in deer and might be of importance to public health.

12.
J Clin Oncol ; 40(22): 2420-2425, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35709465

RESUMO

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically on the based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported.We previously reported significantly improved failure-free survival using gemcitabine plus cisplatin induction chemotherapy in locoregionally advanced nasopharyngeal carcinoma. Here, we present the final overall survival (OS) analysis. In this multicenter, randomized trial, patients were assigned to be treated with concurrent chemoradiotherapy alone (standard therapy, n = 238) or gemcitabine and cisplatin induction chemotherapy before concurrent chemoradiotherapy (n = 242). With a median follow-up of 69.8 months, the induction chemotherapy group had a significantly higher 5-year OS (87.9% v 78.8%, hazard ratio, 0.51 [95% CI 0.34 to 0.78]; P = .001) and a comparable risk of late toxicities (≥ grade 3, 11.3% v 11.4%). Notably, the depth of the tumor response to induction chemotherapy correlated significantly and positively with survival (complete response v partial response v stable/progressive disease, 5-year OS, 100% v 88.4% v 61.5%, P = .005). Besides, patients with a low pretreatment cell-free Epstein-Barr virus DNA load (< 4,000 copies/mL) might not benefit from induction chemotherapy (5-year OS, 90.6% v 91.4%, P = .77). In conclusion, induction chemotherapy before concurrent chemoradiotherapy improved OS significantly in patients with locally advanced nasopharyngeal carcinoma, without increasing the risk of late toxicities. Tumor response to induction chemotherapy and pretreatment cell-free Epstein-Barr virus DNA might be useful to guide individualized treatment.


Assuntos
Quimioterapia de Indução , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Quimiorradioterapia , Cisplatino/uso terapêutico , Desoxicitidina/análogos & derivados , Herpesvirus Humano 4 , Humanos , Quimioterapia de Indução/efeitos adversos , Carcinoma Nasofaríngeo/tratamento farmacológico , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/radioterapia , Análise de Sobrevida , Gencitabina
13.
Chemosphere ; 301: 134780, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35500633

RESUMO

Active samplers are widely used in the quantification of gaseous semi-volatile organic compounds (SVOCs). A sampling tube is often assembled upstream of the sampler, especially in the active samplers used for separating the particle-phase and gas-phase SVOCs and in the newly-designed active sampler based on solid-phase microextraction (SPME). However, gaseous SVOCs can be easily adsorbed by the sampling tube, which may induce significant errors to the quantitative results. Taking the SPME-based active sampler as an example, a mass-transfer model was developed to characterize the sampling-tube loss of gaseous SVOCs. Experiments involving six SVOCs were conducted. The model predictions (with a best-fit surface/air partition coefficient of SVOCs) were found to be consistent with the measurements. Both model predictions and experimental data indicated that the measured concentrations were significantly lower than the actual concentration (around 60% lower) due to the sampling-tube loss. The duration of sampling-tube loss (τe, minutes to days) varied with the volatility of SVOCs (vapor pressure, Vp), i.e., log τe linearly increased as increasing log Vp. The relationship could be helpful for determining the sampling strategies to eliminate (reduce) the effects of sampling-tube loss according to the volatility of SVOCs. The above conclusions may be also applicable for other active samplers of gaseous SVOCs. However, further studies are required to quantify the effects of sampling-tube loss for other active samplers due to the difference in the size and shape of the sampling tube between them and the SPME-based active sampler. The corresponding mass-transfer model and experimental procedure may require adjustment as appropriate.


Assuntos
Poluentes Atmosféricos , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Gases/análise , Microextração em Fase Sólida , Compostos Orgânicos Voláteis/análise
14.
Cancer Cell Int ; 21(1): 604, 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34772421

RESUMO

BACKGROUND: We aimed to comprehensively investigate the optimal cumulative cisplatin dose during concurrent chemoradiotherapy (CC-CCD) for locoregionally advanced nasopharyngeal carcinoma (CA-LANPC) with different tumor responses after neoadjuvant chemotherapy (NAC). METHODS: Patients with CA-LANPC who underwent NAC followed by cisplatin-based concurrent chemoradiotherapy were retrospectively analyzed. Evaluation of tumor response in patients was conducted by Response Evaluation Criteria for Solid Tumor (RECIST) 1.1 after two to four cycles NAC. Multivariate Cox proportional hazards models were used for prognosis. Recursive partitioning analysis (RPA) was conducted to classify participates and predict disease-free survival (DFS). RESULTS: One hundred and thirty-two patients with favorable response after NAC were included. The median CC-CCD was 163 mg/m2 (IQR, 145-194 mg/m2), and 160 mg/m2 was selected as the cutoff point to group patients into low and high CC-CCD groups (< 160 vs. ≥ 160 mg/m2). There was significant improvement in 5-year DFS (91.2% vs. 72.6%; P = 0.003) for patients receiving high CC-CCD compared to those receiving low CC-CCD. Multivariate analysis revealed that CC-CCD, T stage, and Epstein-Barr virus (EBV) DNA were independent prognostic factors for DFS (P < 0.05 for all). Patients were further categorized into two prognostic groups by RPA: the low-risk group (T1-3 disease with regardless of EBV DNA, and T4 disease with EBV DNA < 4000 copy/mL), and the high-risk group (T4 disease with EBV DNA ≥ 4000 copy/mL). Significant 5-year DFS improvement was observed for the high-risk group (P = 0.004) with high CC-CCD. However, DFS improvement was relatively insignificant in the low-risk group (P = 0.073). CONCLUSIONS: CC-CCD was a positive prognostic factor for responders after NAC in CA-LANPC. Furthermore, CC-CCD ≥ 160 mg/m2 could significantly improve DFS in the high-risk group with CA-LANPC, but the benefit of high CC-CCD in the low-risk group needs further study.

15.
Front Genet ; 12: 705337, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34557217

RESUMO

The reintroduction is an important conservation tool to restore a species in its historically distribution area, but the rate of reintroduction success varies across species or regions due to different reasons. Genetic evaluation is important to the conservation management of reintroduced species. Conservation concerns relate to genetic threats for species with a small population size or severely historically bottle-necked species, such as negative consequences associated with loss of genetic diversity and inbreeding. The last 40years have seen a rapid increasing of population size for Père David's deer (Elaphurus davidianus), which originated from a limited founder population. However, the genetic structure of reintroduced Père David's deer has not been investigated in terms of population genomics, and it is still not clear about the evolutionary history of Père David's deer and to what extent the inbreeding level is. Conservation genomics methods were used to reconstruct the demographic history of Père David's deer, evaluate genetic diversity, and characterize genetic structure among 18 individuals from the captive, free-ranging and wild populations. The results showed that 1,456,457 single nucleotide polymorphisms (SNPs) were obtained for Père David's deer, and low levels of genome-wide genetic diversity were observed in Père David's deer compared with Red deer (Cervus elaphus) and Sika deer (Cervus nippon). A moderate population genetic differentiation was detected among three populations of Père David's deer, especially between the captive population in Beijing Père David's deer park and the free-ranging population in Jiangsu Dafeng National Nature Reserve. The effective population size of Père David's deer started to decline ~25.8ka, and the similar levels of three populations' LD reflected the genetic impacts of long-term population bottlenecks in the Père David's deer. The findings of this study could highlight the necessity of individual exchange between different facilities, and genetic management should generally be integrated into conservation planning with other management considerations.

16.
Angew Chem Int Ed Engl ; 60(23): 12949-12954, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33759317

RESUMO

Ag nanoclusters have received increasing attention due to their atomically precise and diverse structures and intriguing optical properties. Nevertheless, the inherent instability of Ag nanoclusters has seriously hindered their practical application. In this work, for the first time, Ag clusters are collaboratively protected by hydrophobic Ti-oxo clusters and alkyne ligands. Initially, a pyramidal Ag5 cluster terminated with t BuC≡C- and CH3 CN was inserted into the cavity of a Ti8 -oxo nanoring to form Ag5 @Ti8 . To overcome the instability of acetonitrile-terminated silver site, such two Ag5 @Ti8 clusters could sandwich an Ag4 unit to form Ag14 -nanorod@Ti16 -oxo-nanoring (Ag14 @Ti16 ), which is peripherally protected by fluorophenyl groups and alkyne caps. This threefold protected (hydrophobic fluorinated organic layer, Ti-O shell, and terminal alkyne ligands) Ag14 @Ti16 exhibits superhydrophobicity and excellent ambient stability, endowing it with solid-state optical limiting characteristics.

17.
Nanoscale ; 13(10): 5292-5299, 2021 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-33660724

RESUMO

Transition metal nitrides are promising mediators for improving the electrochemical performance of lithium-sulfur (Li-S) batteries, but the synthesis of ultrafine and durable nanoparticles in the absence of ammonia gas is still a great challenge. Herein, we reported a new method for the fabrication of ultrafine vanadium nitride (VN) nanoparticles uniformly embedded into N-doped porous carbon using a main-chain imidazolium-based ionic polymer (ImIP) containing metavanadate anions as a precursor. ImIP not only serves as sole carbon and nitrogen sources, but also effectively inhibits the aggregation and coalescence of VN nanoparticles during pyrolysis. Benefiting from the ultrafine particle size, high polarity and good electrocatalytic effects of VN, both redox kinetics of sulfur species and chemical adsorbability toward polysulfides are greatly expedited. The resultant electrode exhibits superior cycling stability with a low average capacity decay rate of 0.035% for 1200 cycles at a high rate of 5 C. This work develops a facile ammonia-free approach to fabricate ultrafine VN nanoparticles for improving electrochemical behaviors of Li-S batteries.

19.
Nanoscale Adv ; 3(12): 3554-3562, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36133714

RESUMO

Due to the easy loss of ions during synthesis or usage, vacancies in perovskite film are ubiquitous, accelerating the degradation of perovskite materials and seriously hampering the stability of perovskite solar cells (PSCs). Herein, to simultaneously compensate for vacancies and reduce ammonium cation loss, a sustained release strategy was proposed by introducing multi-functional capsules consisting of zeolitic imidazolate framework-8 (ZIF-8) encapsulation agent and ammonium iodide salts as interlayer between the perovskite and hole transport layer. In the capsule interlayer, not only are ammonium iodide salts in ZIF-8 pores released to the perovskite layer, compensating for the vacancies, but the ZIF-8 also prevents the organic component of perovskite from evaporating and isolates the perovskite from moisture. As a consequence, decreased trap density, improved device efficiency, and enhanced stability of PSCs are obtained owing to the successful passivation of defects by the introduced capsules. ZIF-8@FAI shows the highest efficiency of 19.13% and a stabilized PCE over 93% of the initial efficiency at maximum power point for 150 h. This work provides a new strategy to improve efficiency and stability of PSCs based on the large family of porous materials.

20.
Onco Targets Ther ; 13: 11991-12001, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33244241

RESUMO

BACKGROUND AND AIM: Some studies have confirmed that miRNA-140 exhibits a suppressive role in gastric cancer, Wilms' tumor. However, the function of miRNA-140 in colorectal cancer has not been completely elucidated. The present study aims to verify TRAF6 as the targeted gene by miRNA-140 which was investigated in colorectal cancer tissues and cells, and its effects on the biological characteristics of colorectal cancer cells were determined, in order to provide an experimental and theoretical basis for the application of TRAF6 in the treatment of colorectal cancer. METHODS: qPCR analyzed miRNA-140 expression levels in colorectal cancer tissues, normal colorectal cancer tissues and colorectal cells including SW480 and HCT116 cancer cells and FHC normal colorectal epithetical cells. A serial biological experiment analyzed miRNA-140 effects on cell proliferation, migration and invasion capacities in SW480 and HCT116 cells. miRNA targeting gene prediction and a dual luciferase assay were used to analyze miRNA-140-targeted TRAF6. qPCR and Western blot analyzed miRNA-140 effects on the mRNA and protein expression of TRAF6. Western blot analyzed miRNA-140 effects on NF-κB/c-jun signaling pathways. Animal studies were performed to investigate the effects of miRNA-140 on colorectal cancer implantation tumor growth. Immunohistochemistry analyzed TRAF6 expression in animal experimentation tumors. RESULTS: miRNA-140 expression is lower in colorectal cancer tissues and colorectal cancer cells. Over-expression of miRNA-140 inhibited the proliferation, migration and invasion capacities of colorectal cancer cells. miRNA-140 targeted the TRAF6 mRNA 3'UTR area and decreased TRAF6 protein expression. miRNA-140 suppressed p-NF-κB/p-c-jun proteins expression. miRNA-140 inhibited colorectal cancer implantation tumor growth in the mice model. CONCLUSION: miRNA-140 targeting TRAF6 affects the progression and growth of colorectal cancer, the mechanism could be miRNA-140 decreasing the TRAF6 expression effects on the NF-κB/c-jun signaling pathways.

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