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1.
Chem Sci ; 15(20): 7586-7595, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38784730

RESUMO

Fabricating three dimensional (3D) supramolecular frameworks (SMFs) into stable crystalline nanosheets remains a great challenge due to the homogeneous and weak inter-building block interactions along 3D directions. Herein, crystalline nanosheets of a 3D SMF with a uniform thickness of 4.8 ± 0.1 nm immobilized with Pt nanocrystals on the surface (Q[8]/Pt NSs) were fabricated via the solid-liquid reaction between cucurbit[8]uril/H2PtCl6 single crystals and hydrazine hydrate with the help of gas and heat yielded during the reaction process. A series of experiments and theoretical calculations reveal the ultrahigh stability of Q[8]/Pt NSs due to the high density hydrogen bonding interaction among neighboring Q[8] molecules. This in turn endows Q[8]/Pt NSs with excellent photocatalytic and continuous thermocatalytic CO oxidation performance, representing the thus-far reported best Pt nano-material-based catalysts.

2.
Angew Chem Int Ed Engl ; : e202404156, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38619506

RESUMO

The synthesis and characterization of porphyrin center regulated three-dimensional covalent organic frameworks (COFs) with 2-fold interpenetrated scu or sqc topology have been investigated. These COFs exhibit unique structural features and properties, making them promising candidates for photocatalytic applications in CO2 reduction and artemisinin synthesis. The porphyrin center serves as an anchor for metal ions, allowing precise control over structures and functions of the frameworks. Furthermore, the metal coordination within the framework imparts desirable catalytic properties, enabling their potential use in photocatalytic reactions. Overall, these porphyrin center regulated metal-controlled COFs offer exciting opportunities for the development of advanced materials with tailored functionalities.

3.
Angew Chem Int Ed Engl ; 63(15): e202401014, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38334002

RESUMO

Developing high connectivity (>8) three-dimensional (3D) covalent organic frameworks (COFs) towards new topologies and functions remains a great challenge owing to the difficulty in getting high connectivity organic building blocks. This however represents the most important step towards promoting the diversity of COFs due to the still limited dynamic covalent bonds available for constructing COFs at this stage. Herein, highly connected phthalocyanine-based (Pc-based) 3D COFs MPc-THHI-COFs (M=H2, Ni) were afforded from the reaction between 2,3,9,10,16,17,23,24-octacarboxyphthalocyanine M(TAPc) (M=H2, Ni) and 5,5',5'',5''',5'''',5'''''-(triphenylene-2,3,6,7,10,11-hexayl)hexa(isophthalohydrazide) (THHI) with 12 connecting sites. Powder X-ray diffraction analysis together with theoretical simulations and transmission electron microscopy reveals their crystalline nature with an unprecedented non-interpenetrated shp topology. Experimental and theoretical investigations disclose the broadened visible light absorption range and narrow optical band gap of MPc-THHI-COFs. This in combination with their 3D nanochannels endows them with efficient photocatalysis performance for H2O2 generation from O2 and H2O via 2e- oxygen reduction reaction and 2e- water oxidation reaction under visible-light irradiation (λ >400 nm). This work provides valuable result for the development of high connectivity functional COFs towards diverse application potentials.

4.
Small ; : e2310147, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38377273

RESUMO

Fabricating COFs-based electrocatalysts with high stability and conductivity still remains a great challenge. Herein, 2D polyimide-linked phthalocyanine COF (denoted as NiPc-OH-COF) is constructed via solvothermal reaction between tetraanhydrides of 2,3,9,10,16,17,23,24-octacarboxyphthalocyaninato nickel(II) and 2,5-diamino-1,4-benzenediol (DB) with other two analogous 2D COFs (denoted as NiPc-OMe-COF and NiPc-H-COF) synthesized for reference. In comparison with NiPc-OMe-COF and NiPc-H-COF, NiPc-OH-COF exhibits enhanced stability, particularly in strong NaOH solvent and high conductivity of 1.5 × 10-3  S m-1 due to the incorporation of additional strong interlayer hydrogen bonding interaction between the O-H of DB and the hydroxy "O" atom of DB in adjacent layers. This in turn endows the NiPc-OH-COF electrode with ultrahigh CO2 -to-CO faradaic efficiency (almost 100%) in a wide potential range from -0.7 to -1.1 V versus reversible hydrogen electrode (RHE), a large partial CO current density of -39.2 mA cm-2 at -1.1 V versus RHE, and high turnover number as well as turnover frequency, amounting to 45 000 and 0.76 S-1 at -0.80 V versus RHE during 12 h lasting measurement.

5.
PLoS One ; 19(2): e0296757, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38306367

RESUMO

Ticks are important vectors of zoonotic diseases and play a major role in the circulation and transmission of many rickettsial species. The aim of this study was to investigate the carriage of Candidatus Rickettsia tarasevichiae (CRT) in a total of 1168 ticks collected in Inner Mongolia to elucidate the potential public health risk of this pathogen, provide a basis for infectious disease prevention, control and prediction and contribute diagnostic ideas for clinical diseases that present with fever in populations exposed to ticks. A total of four tick species, Haemaphysalis concinna (n = 21), Dermacentor nuttalli (n = 122), Hyalomma marginatum (n = 148), and Ixodes persulcatus (n = 877), were collected at nine sampling sites in Inner Mongolia, China, and identified by morphological and molecular biological methods. Reverse transcription PCR targeting the 16S ribosomal RNA (rrs), gltA, groEL, ompB and Sca4 genes was used to detect CRT DNA. Sequencing was used for pathogen species confirmation. The molecular epidemiological analysis showed that three species of ticks were infected with CRT, and the overall positive rate was as high as 42%. The positive rate of I. persulcatus collected in Hinggan League city was up to 96%, and that of I. persulcatus collected in Hulun Buir city was 50%. The pool positive rates of D. nuttalli and H. marginatum collected in Bayan Nur city and H. concinna collected in Hulun Buir city were 0%, 28% and 40%, respectively. This study revealed the high prevalence of CRT infection in ticks from Inner Mongolia and the first confirmation of CRT detected in H. marginatum in China. The wide host range and high infection rate in Inner Mongolia may dramatically increase the exposure of CRT to humans and other vertebrates. The role of H. marginatum in the transmission of rickettsiosis and its potential risk to public health should be further considered.


Assuntos
Ixodes , Ixodidae , Infecções por Rickettsia , Rickettsia , Humanos , Animais , Ixodidae/microbiologia , Rickettsia/genética , Ixodes/microbiologia , Infecções por Rickettsia/microbiologia , Zoonoses
6.
Nat Commun ; 15(1): 678, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38263147

RESUMO

Realization of stable and industrial-level H2O2 electroproduction still faces great challenge due large partly to the easy decomposition of H2O2. Herein, a two-dimensional dithiine-linked phthalocyaninato cobalt (CoPc)-based covalent organic framework (COF), CoPc-S-COF, was afforded from the reaction of hexadecafluorophthalocyaninato cobalt (II) with 1,2,4,5-benzenetetrathiol. Introduction of the sulfur atoms with large atomic radius and two lone-pairs of electrons in the C-S-C linking unit leads to an undulated layered structure and an increased electron density of the Co center for CoPc-S-COF according to a series of experiments in combination with theoretical calculations. The former structural effect allows the exposition of more Co sites to enhance the COF catalytic performance, while the latter electronic effect activates the 2e- oxygen reduction reaction (2e- ORR) but deactivates the H2O2 decomposition capability of the same Co center, as a total result enabling CoPc-S-COF to display good electrocatalytic H2O2 production performance with a remarkable H2O2 selectivity of >95% and a stable H2O2 production with a concentration of 0.48 wt% under a high current density of 125 mA cm-2 at an applied potential of ca. 0.67 V versus RHE for 20 h in a flow cell, representing the thus far reported best H2O2 synthesis COFs electrocatalysts.

7.
J Proteome Res ; 23(2): 797-808, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38212294

RESUMO

The objective of this study was to construct a prognostic model by utilizing serine/glycine metabolism-related genes (SGMGs), thus establishing a risk score for lung adenocarcinoma (LUAD). Based on the TCGA-LUAD and SGMG data set, two subtypes with different SGMG expression levels were identified by clustering analysis. Thirteen differential expression genes were used to construct RiskScore by Cox regression. GSE72094 data set was used for validation. The survival characteristics, immune features, and potential benefits of chemotherapy drugs were analyzed for two risk groups. RiskScore was constructed based on the genes ABCC12, RIC3, CYP4B1, SFTPB, CACNA2D2, IGF2BP1, NTSR1, DKK1, CREG2, PITX3, RGS20, FETUB, and IGFBP1. Patients in the low-risk (LR) group exhibited a superior overall survival. In addition, aDCs, iDSs, mast cells, neutrophils, HLA, and type II IFN were more abundant in the LR group with higher IPS scores and lower TIDE scores. In contrast, NK cells, APC coinhibition, and MHC-I were more common in the high-risk (HR) group, which may be more sensitive to chemotherapy drugs such as cisplatin, oxaliplatin, and nilotinib. RiskScore was a promising biomarker that can be used to distinguish LUAD prognosis, immune features, and sensitivity to chemotherapy drugs.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Prognóstico , Fatores de Risco , Adenocarcinoma de Pulmão/genética , Neoplasias Pulmonares/genética , Glicina , Proteínas Repressoras
8.
Sci Rep ; 13(1): 21963, 2023 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-38082032

RESUMO

Damage to lamellar keratinocytes, an essential cellular component of the epidermal layer of hoof tissue, can have a detrimental effect on hoof health and the overall production value of dairy cows. We isolated and cultured cow lamellar keratinocytes using the Dispase II and collagenase methods. We purified them by differential digestion and differential velocity adherent methods at each passaging and identified them by keratin 14 immunofluorescence. We established an in vitro model of inflammation in laminar keratinocytes using LPS and investigated whether chicoric acid protects against inflammatory responses by inhibiting the activation of the TLR4/MAPK/NF-κB signaling pathway. The results showed that cow lamellar keratinocytes were successfully isolated and cultured by Dispase II combined with the collagenase method. In the in vitro inflammation model established by LPS, the Chicoric acid decreased the concentration of inflammatory mediators (TNF-α, IL-1ß, and IL-6), down-regulated the mRNA expression of TLR4 and MyD88 (P < 0.01), down-regulated the expression of TLR4, MyD88, p-ERK, p-p38, IKKß, p-p65, p-p50 (P < 0.05), and increased the IκBα protein expression (P < 0.05). In conclusion, Chicoric acid successfully protected cow lamellar keratinocytes from LPS-induced inflammatory responses by modulating the TLR4/MAPK/NF-κB signaling pathway and downregulating inflammatory mediators.


Assuntos
Lipopolissacarídeos , NF-kappa B , Feminino , Bovinos , Animais , NF-kappa B/metabolismo , Lipopolissacarídeos/toxicidade , Receptor 4 Toll-Like/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Transdução de Sinais , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Queratinócitos/metabolismo , Mediadores da Inflamação/metabolismo , Colagenases/metabolismo
9.
Parasite ; 30: 58, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38084939

RESUMO

Ticks can carry multiple pathogens, and Inner Mongolia's animal husbandry provides excellent environmental conditions for ticks. This study characterized the microbiome of ticks from different geographical locations in Inner Mongolia; 905 Dermacentor nuttalli and 36 Ixodes persulcatus were collected from sheep in three main pasture areas and from bushes within the forested area. Mixed DNA samples were prepared from three specimens from each region and tick species. Microbial diversity was analyzed by 16S rRNA sequencing, and α and ß diversity were determined. The predominant bacterial genera were Rickettsia (54.60%), including Rickettsiales bacterium Ac37b (19.33%) and other Rickettsia (35.27%), Arsenophonus (11.21%), Candidatus Lariskella (10.84%), and Acinetobacter (7.17%). Rickettsia bellii was identified in I. persulcatus, while Rickettsiales bacterium Ac37b was found in D. nuttalli from Ordos and Chifeng. Potential Rickettsia and Anaplasma coinfections were observed in the Ordos region. Tick microbial diversity analysis in Inner Mongolia suggests that sheep at the sampling sites were exposed to multiple pathogens.


Title: Diversité microbienne des tiques et nouvelle espèce de Rickettsia du groupe du typhus (bactérie Rickettsiales Ac37b) en Mongolie intérieure, Chine. Abstract: Les tiques peuvent être porteuses de plusieurs agents pathogènes et l'élevage en Mongolie intérieure offre d'excellentes conditions environnementales pour les tiques. Cette étude a caractérisé le microbiome des tiques de différentes zones géographiques de Mongolie intérieure; 905 Dermacentor nuttalli et 36 Ixodes persulcatus ont été collectés sur des moutons dans trois principales zones de pâturage et dans des buissons de la zone forestière. Des échantillons d'ADN mixtes ont été préparés à partir de trois spécimens de chaque région et espèce de tique. La diversité microbienne a été analysée par séquençage de l'ARNr 16S et la diversité α et ß a été déterminée. Les genres bactériens prédominants étaient les Rickettsia (54,60 %), dont la bactérie Rickettsiales Ac37b (19,33 %) et d'autres Rickettsia (35,27 %), Arsenophonus (11,21 %), Candidatus Lariskella (10,84 %) et Acinetobacter (7,17 %). Rickettsia bellii a été identifiée chez I. persulcatus, tandis que la bactérie Rickettsiales Ac37b a été trouvée chez D. nuttalli d'Ordos et Chifeng. Des co-infections potentielles à Rickettsia et Anaplasma ont été observées dans la région d'Ordos. L'analyse de la diversité microbienne des tiques en Mongolie intérieure montre que les moutons présents sur les sites d'échantillonnage sont exposés à plusieurs agents pathogènes.


Assuntos
Ixodes , Rickettsia , Doenças dos Ovinos , Tifo Epidêmico Transmitido por Piolhos , Animais , Ovinos , Rickettsiales/genética , RNA Ribossômico 16S/genética , Rickettsia/genética , Ixodes/microbiologia , China/epidemiologia , Doenças dos Ovinos/epidemiologia
10.
Clin Respir J ; 17(9): 884-892, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37553792

RESUMO

BACKGROUND: Cancer stem cells are pivotal in cancer progression and therapy, including lung adenocarcinoma (LUAD). High NCAPG level is implicated in malignant tumorigenesis, but investigations on NCAPG and LUAD stem cells are warranted. Hence, projecting the impact of NCAPG on cell stemness and the targeted therapy for LUAD is of the essence. METHODS: Bioinformatics analyzed NCAPG expression in LUAD tissues. qRT-PCR assayed NCAPG expression in LUAD cells. CCK-8 assessed cell viability and cell sphere-forming assay measured sphere-forming ability. Western blot assessed expression of stem cell-related markers (CD133, CD44, Oct-4) and specific genes (HK2, PKM2, LDHA) related to glycolysis metabolism pathway. Cellular glycolytic capacity was assayed by glycolytic metabolites pyruvic acid, lactate, citrate, and malate assay kits, and extracellular acidification rate and oxygen consumption rate analyzers. RESULTS: NCAPG was upregulated in LUAD and enriched in the aerobic glycolysis pathway, and its expression was positively correlated with that of glycolytic marker genes. Cell function assays revealed that NCAPG stimulated proliferation, stemness, and glycolytic activity of LUAD cells. Rescue experiments unveiled that 2-DG (glycolysis inhibitor) was able to reverse the stimulative impact of NCAPG overexpression on proliferation, stemness, and glycolytic activity of LUAD cells. CONCLUSION: NCAPG stimulated LUAD cell stemness through activation of glycolysis pathway. NCAPG may be possible biomarker for diagnosis and target for treatment of LUAD.


Assuntos
Adenocarcinoma de Pulmão , Adenocarcinoma , Neoplasias Pulmonares , Humanos , Adenocarcinoma de Pulmão/genética , Adenocarcinoma/genética , Citratos , Western Blotting , Neoplasias Pulmonares/genética , Proliferação de Células , Linhagem Celular Tumoral , Proteínas de Ciclo Celular
11.
Angew Chem Int Ed Engl ; 62(33): e202305144, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37341154

RESUMO

Utilization of rigid, highly connected organic linkers is critical for the reticular synthesis of functional metal-organic frameworks (MOFs). However, highly-stable MOFs (e.g. Al/Cr/Zr-based MOFs) based on rigid ligands with more than 6 coordinating functions have been rarely achieved thus far. Herein, we describe the construction of two bcu Zr-based MOFs (named ZrMOF-1 and ZrMOF-2) from peripherally extended pentiptycene ligands (H8 PEP-1 and H8 PEP-2) with rigid quadrangular prism shape possessing 8 carboxylic groups at the prism vertices. Particularly, ZrMOF-1 exhibits microporous structure with large Bruno-Emmett-Teller surface area and high water stability, endowing it a promising water harvesting material with a high water uptake capacity of 0.83 gH2O gMOF -1 at P/P0 =0.90 and 25 °C, a steep uptake at a low P/P0 of 0.30, and excellent durability over 500 water adsorption-desorption cycles. Moreover, self-consistent charge density functional tight-binding calculations were carried out, rationalizing the water adsorbing process and amount in ZrMOF-1.

12.
J Vet Med Sci ; 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37258222

RESUMO

Damage to lamellar keratinocytes, an essential cellular component of the epidermal layer of hoof tissue, can have a detrimental effect on hoof health and the overall production value of dairy cows. In this study, we described four digestion methods: trypsin method, collagenase method, Dispase II combined with trypsin method, and Dispase II combined with collagenase method, compared their isolation and culture efficiency, observed primary cell and subculture cell growth, and according to the difference of digestion time and apposition time of fibroblasts and keratinocytes, lamellar keratinocytes were purified by differential digestion method as well as differential velocity adherent method at each passaging and identified specific keratin 14 of keratinocytes using immunofluorescence. The results revealed that the lamellar keratinocytes isolated using Dispase II combined with the collagenase method increased rapidly, the number of cells in the offspring 4 generation was high, and the cells demonstrated positive expression of keratin,which facilitated the subsequent purification.

13.
Angew Chem Int Ed Engl ; 62(18): e202302808, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-36890114

RESUMO

Rational regulation of electronic structures and functionalities of framework materials still remains challenging. Herein, reaction of 4,4',4''-nitrilo-tribenzhydrazide with tris(µ2 -4-carboxaldehyde-pyrazolato-N,N')-tricopper (Cu3 Py3 ) generates the crystalline copper organic framework USTB-11(Cu). Post-modification with divalent nickel ions affords the heterometallic framework USTB-11(Cu,Ni). Powder X-ray diffraction and theoretical simulations reveal their two-dimensional hexagonal structure geometry. A series of advanced spectroscopic techniques disclose the mixed CuI /CuII state nature of Cu3 Py3 in USTB-11(Cu,Ni) with a uniform bistable Cu3 4+ (CuI 2 CuII ) : Cu3 5+ (CuI CuII 2 ) (ca. 1 : 3) oxidation state, resulting in a significantly improved formation efficiency of the charge-separation state. This endows the Ni sites with enhanced activity and USTB-11(Cu,Ni) with outstanding photocatalytic CO2 to CO performance with a conversion rate of 22 130 µmol g-1 h-1 and selectivity of 98 %.

14.
J Am Chem Soc ; 145(14): 8141-8149, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-36989190

RESUMO

Lithium-sulfur batteries (LSBs) have been considered as a promising candidate for next-generation energy storage devices, which however still suffer from the shuttle effect of the intermediate lithium polysulfides (LiPSs). Covalent-organic frameworks (COFs) have exhibited great potential as sulfur hosts for LSBs to solve such a problem. Herein, a pentiptycene-based D2h symmetrical octatopic polyaldehyde, 6,13-dimethoxy-2,3,9,10,18,19,24,25-octa(4'-formylphenyl)pentiptycene (DMOPTP), was prepared and utilized as a building block toward preparing COFs. Condensation of DMOPTP with 4-connected tetrakis(4-aminophenyl)methane affords an expanded [8 + 4] connected network 3D-flu-COF, with a flu topology. The non-interpenetrated nature of the flu topology endows 3D-flu-COF with a high Brunauer-Emmett-Teller surface area of 2860 m2 g-1, large octahedral cavities, and cross-linked tunnels in the framework, enabling a high loading capacity of sulfur (∼70 wt %), strong LiPS adsorption capability, and facile ion diffusion. Remarkably, when used as a sulfur host for LSBs, 3D-flu-COF delivers a high capacity of 1249 mA h g-1 at 0.2 C (1.0 C = 1675 mA g-1), outstanding rate capability (764 mA h g-1 at 5.0 C), and excellent stability, representing one of the best results among the thus far reported COF-based sulfur host materials for LSBs and being competitive with the state-of-the-art inorganic host materials.

15.
J Am Chem Soc ; 144(46): 21328-21336, 2022 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-36350764

RESUMO

Artificial photosynthesis of H2O2 from O2 reduction provides an energy-saving, safe, and green approach. However, it is still critical to develop highly active and selective 2e- oxygen reduction reaction photocatalysts for efficient H2O2 production owing to the unsatisfactory photosynthesis productivity. Herein, two new two-dimensional piperazine-linked CoPc-based covalent organic frameworks (COFs), namely, CoPc-BTM-COF and CoPc-DAB-COF, were afforded from the nucleophilic substitution reaction of hexadecafluorophthalocyaninato cobalt(II) (CoPcF16) with 1,2,4,5-benzenetetramine (BTM) or 3,3'-diaminobenzidine (DAB). Powder X-ray diffraction analysis in combination with electron microscopy and a series of spectroscopic technologies reveals their crystalline porous framework with a fully conjugated structure and eclipsed π-stacking model. Ultraviolet-visible diffuse reflectance absorption spectra unveil their excellent light absorption capacity in a wide range of 400-1000 nm. This, together with their enhanced photo-induced charge separation and transport efficiency as disclosed by photocurrent response and photoluminescence measurements, endows the as-prepared piperazine-linked CoPc-based COFs with superior photocatalytic activity toward O2-to-H2O2 conversion under visible-light irradiation (λ > 400 nm). In particular, CoPc-BTM-COF exhibits a record-high H2O2 yield of 2096 µmol h-1 g-1 among the COF-based photocatalysts and an impressive apparent quantum yield of 7.2% at 630 nm. The present result should be helpful for fabricating high-performance and low-cost photocatalysts for visible-light-driven H2O2 photosynthesis.


Assuntos
Peróxido de Hidrogênio , Luz , Piperazina , Fotossíntese
16.
J Am Chem Soc ; 144(37): 17209-17218, 2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36084308

RESUMO

Developing conjugated three-dimensional (3D) covalent organic frameworks (COFs) still remains an extremely difficult task due to the lack of enough conjugated 3D building blocks. Herein, condensation between an 8-connected pentiptycene-based D2h building block (DMOPTP) and 4-connected square-planar linkers affords two 3D COFs (named 3D-scu-COF-1 and 3D-scu-COF-2). A combination of the 3D homoaromatic conjugated structure of the former building block with the 2D conjugated structure of the latter linking units enables the π-electron delocalization over the whole frameworks of both COFs, endowing them with excellent conductivities of 3.2-3.5 × 10-5 S cm-1. In particular, the 3D rigid quadrangular prism shape of DMOPTP guides the formation of a twofold interpenetrated scu 3D topology and high-connected permanent porosity with a large Brunauer-Emmett-Teller (BET) surface area of 2340 and 1602 m2 g-1 for 3D-scu-COF-1 and 3D-scu-COF-2, respectively, ensuring effective small molecule storage and mass transport characteristics. This, in combination with their good charge transport properties, renders them promising sulfur host materials for lithium-sulfur batteries (LSBs) with high capacities (1035-1155 mA h g-1 at 0.2 C, 1 C = 1675 mA g-1), excellent rate capabilities (713-757 mA h g-1 at 5.0 C), and superior cycling stability (71-83% capacity retention at 2.0 C after 500 cycles), surpassing the most of organic LSB cathodes reported thus far.

17.
Parasit Vectors ; 15(1): 286, 2022 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-35934699

RESUMO

BACKGROUND: The genus Rickettsia contains the lineages spotted fever group (SFG), typhus group (TG), and transitional group (TRG). The spotted fever group Rickettsia (SFGR) is transmitted by ticks. The tick species Dermacentor nuttalli is considered the main vector carrying SFGR in Inner Mongolia. Studying the genetic diversity and population structure of Rickettsia is essential for developing effective control strategies and predicting evolutionary trends of Rickettsia. METHODS: In 2019 we collected 408 D. nuttalli in the Inner Mongolia Autonomous Region, detected the percentage of Rickettsia-positive specimens, and characterized the haplotypes. From the Rickettsia-positive ticks, the gltA and ompA genes were extracted, amplified, and sequenced. RESULTS: Ten haplotypes of the gltA gene and 22 haplotypes of the ompA gene were obtained. The phylogenetic analysis showed that the haplotypes G1-G7 and G9 of the gltA gene cluster with Rickettsia raoultii, while G8 and G10 cluster with Rickettsia sibirica. Haplotypes O1-O15, O18 and O20-O22 of the ompA gene cluster with R. raoultii, while O16 and O19 cluster with R. sibirica. The average haplotype diversity was 0.3 for gltA and 0.7 for ompA. The average nucleotide diversity was greater than 0.05. Neutrality tests were nonsignificant for Tajima's D results and Fu's Fs results. The fixation index values (FST) showed that the degree of genetic differentiation between most sampled populations was small (FST < 0.05), whereas some populations showed a medium (FST > 0.05) or large (FST > 0.15) degree of differentiation. Analysis of molecular variance (AMOVA) revealed that the variation within populations was greater than that between populations. The mismatch analysis of Rickettsia showed double peaks. CONCLUSIONS: We found two Rickettsia spp. (R. raoultii and R. sibirica). The high genetic disparity of Rickettsia allows for easy adaption to different environments. Genetic differentiation between populations is small, and Rickettsia populations do not show a geographically differentiated structure. The high rates of retention and infection of Rickettsia in D. nuttalli together with the animal husbandry exchange in Inner Mongolia gradually led to the harmonization of genetic characteristics of Rickettsia across various regions. Overall, the significant genetic diversity and geographical structure of Rickettsia in D. nuttalli are critical for SFGR control.


Assuntos
Dermacentor , Ixodidae , Rickettsia , Rickettsiose do Grupo da Febre Maculosa , Animais , China/epidemiologia , Dermacentor/genética , Variação Genética , Ixodidae/microbiologia , Filogenia , Rickettsia/genética , Rickettsiose do Grupo da Febre Maculosa/epidemiologia
18.
Chem Sci ; 13(23): 7014-7020, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35774155

RESUMO

Chiral recognition and discrimination is not only of significance in biological processes but also a powerful method to fabricate functional supramolecular materials. Herein, a pair of heterochiral porous organic cages (HPOC-1), out of four possible enantiomeric products, with mirror stereoisomeric crystal structures were cleanly prepared by condensation occurring in the exclusive combination of cyclohexanediamine and binaphthol-based tetraaldehyde enantiomers. Nuclear magnetic resonance and luminescence spectroscopy have been employed to monitor the assembly process of HPOC-1, revealing the clean formation of heterochiral organic cages due to the enantioselective recognition of (S,S)-binaphthol towards (R,R)-cyclohexanediamine derivatives and vice versa. Interestingly, HPOC-1 exhibits circularly polarized luminescence and enantioselective recognition of chiral substrates according to the circular dichroism spectral change. Theoretical simulations have been carried out, rationalizing both the enantioselective assembly and recognition of HPOC-1.

19.
J Mater Chem B ; 10(28): 5487-5492, 2022 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-35792602

RESUMO

By combining an electron-rich triazatruxene unit (TAT) to an electron-deficient zinc porphyrin fluorophore (ZnPor) via an ethynyl bridge, a new two-photon fluorescent viscosity rotor (TAT-ZnPor) with typical donor-π-acceptor (D-π-A) electronic configuration was developed for the ratiometric two-photon fluorescent detection of intracellular viscosity. The TAT-ZnPor dyad exhibited highly improved fluorescence quantum yield (Φem = 0.40) and two-photon absorption cross-section (δTPA = 811 GM) in comparison to the individual components. In the methanol/glycerol system, TAT-ZnPor showed sensitive fluorescence responses toward the change of viscosity. Upon elevating the viscosity from 0.59 to 947 cp, the blue emission band around 410 nm gradually enhanced, while the red band at 647 nm concomitantly quenched, leading to a remarkable intensity ratio (I410/I647) change from 0.70 to 81 (116-fold). TAT-ZnPor also displayed good cell imaging performance under one- and two-photon excitation, and strong mitochondria targeting ability in living cells, thus was successfully applied in detecting the change of mitochondrial viscosity during the nystatin-induced degeneration.


Assuntos
Porfirinas , Carbazóis , Corantes Fluorescentes , Fótons , Viscosidade
20.
Chemistry ; 28(51): e202201125, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-35699688

RESUMO

A systematic investigation to arrange the typical anti-aromatic porphyrinoids in sequence was performed. Based on density functional theory calculations, six rules are summarized to obtain the high-performance anti-aromatic porphyrinoids: (1) when two atoms are deleted/added on the 18π electron current ring flowing pipe, we will immediately obtain a 16π/20π electron anti-aromatic system; (2) it is a good idea to increase the number of pyrrole/thiophen/furan units on the π-electron current ring flowing pipe; (3) the heteroatom selecting order is -O- (optimal choice), -NH- (second choice), and -S- (last choice); (4) it is worth noting that the C-C=C-C unit is not beneficial for the anti-aromatic properties; (5) it is very significant to avoid the crowded environment in the core space of an anti-aromatic molecule. In this view, -O- is much better than -S- and -NH-; (6) the "circular" skeleton is much better than an "ellipse-like", "rectangular", or "parallelogram-like" one.


Assuntos
Porfirinas , Elétrons , Estrutura Molecular , Pirróis
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