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1.
Proc Natl Acad Sci U S A ; 119(12): e2119588119, 2022 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-35290114

RESUMO

SignificanceAlthough most studies of the genetic regulation of genome stability involve an analysis of mutations within the coding sequences of genes required for DNA replication or DNA repair, recent studies in yeast show that reduced levels of wild-type enzymes can also produce a mutator phenotype. By whole-genome sequencing and other methods, we find that reduced levels of the wild-type DNA polymerase ε in yeast greatly increase the rates of mitotic recombination, aneuploidy, and single-base mutations. The observed pattern of genome instability is different from those observed in yeast strains with reduced levels of the other replicative DNA polymerases, Pol α and Pol δ. These observations are relevant to our understanding of cancer and other diseases associated with genetic instability.


Assuntos
DNA Polimerase II , Saccharomyces cerevisiae , DNA Polimerase II/metabolismo , Replicação do DNA/genética , Instabilidade Genômica/genética , Humanos , Mutação , Saccharomyces cerevisiae/metabolismo
2.
Inorg Chem ; 63(16): 7430-7441, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38605566

RESUMO

Most nonoxide catalysts based on transition metal elements will inevitably change their primitive phases under anodic oxidation conditions in alkaline media. Establishing a relationship between the bulk phase and surface evolution is imperative to reveal the intrinsic catalytic active sites. In this work, it is demonstrated that the introduction of Fe facilitates the phase transition of orthorhombic CoSe2 into its cubic counterpart and then accelerates the Co-Fe hydroxide layer generation on the surface during electrocatalytic oxygen evolution reaction (OER). As a result, the Fe-doped cubic CoSe2 catalyst exhibits a significantly enhanced activity with a considerable overpotential decrease of 79.9 and 66.9 mV to deliver 10 mA·cm-2 accompanied by a Tafel slope of 48.0 mV·dec-1 toward OER when compared to orthorhombic CoSe2 and Fe-doped orthorhombic CoSe2, respectively. Density functional theory (DFT) calculations reveal that the introduction of Fe on the surface hydroxide layers will tune electron density around Co atoms and raise the d-band center. These findings will provide deep insights into the surface reconstitution of the OER electrocatalysts based on transition metal elements.

3.
J Asian Nat Prod Res ; : 1-9, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38859556

RESUMO

Twenty 3-acyloxymaltol/ethyl maltol derivatives (7a-j and 8a-j) were synthesized and evaluated in vitro for their anti-oomycete activity against Phytophthora capsici, respectively. Among all of twenty derivatives, more than half of the compounds 7f, 7h, 8a-h and 8j had anti-oomycete activity higher than the positive control zoxamide (EC50 = 22.23 mg/L), and the EC50 values of 18.66, 20.32, 12.80, 16.18, 10.59, 14.98, 16.80, 10.36, 15.32, 12.64, and 13.59 mg/L, respectively. Especially, compounds 8c and 8f exhibited the best anti-oomycete activity against P. capsici with EC50 values of 10.59 and 10.36 mg/L, respectively. Overall, hydroxyl group of maltol/ethyl maltol is important active modification site.

4.
Angew Chem Int Ed Engl ; 63(13): e202314876, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38305641

RESUMO

The carbonate electrolyte chemistry is a primary determinant for the development of high-voltage lithium metal batteries (LMBs). Unfortunately, their implementation is greatly plagued by sluggish electrode interfacial dynamics and insufficient electrolyte thermodynamic stability. Herein, lithium trifluoroacetate-lithium nitrate (LiTFA-LiNO3 ) dual-salt additive-reinforced carbonate electrolyte (LTFAN) is proposed for stabilizing high-voltage LMBs. We reveal that 1) the in situ generated inorganic-rich electrode-electrolyte interphase (EEI) enables rapid interfacial dynamics, 2) TFA- preferentially interacts with moisture over PF6 - to strengthen the moisture tolerance of designed electrolyte, and 3) NO3 - is found to be noticeably enriched at the cathode interface on charging, thus constructing Li+ -enriched, solvent-coordinated, thermodynamically favorable electric double layer (EDL). The superior moisture tolerance of LTFAN and the thermodynamically stable EDL constructed at cathode interface play a decisive role in upgrading the compatibility of carbonate electrolyte with high-voltage cathode. The LMBs with LTFAN realize 4.3 V-NCM523/4.4 V-NCM622 superior cycling reversibility and excellent rate capability, which is the leading level of documented records for carbonate electrode.

5.
Angew Chem Int Ed Engl ; 63(14): e202319662, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38366812

RESUMO

Owing to their distinctive 1,3-dipolar structure, the catalytic asymmetric hydrogenation of nitrones to hydroxylamines has been a formidable and longstanding challenge, characterized by intricate enantiocontrol and susceptibility to N-O bond cleavage. In this study, the asymmetric hydrogenation and transfer hydrogenation of nitrones were accomplished with a tethered TsDPEN-derived cyclopentadienyl rhodium(III) catalyst (TsDPEN: p-toluenesulfonyl-1,2-diphenylethylene-1,2-diamine), the reaction proceeds via a novel 7-membered cyclic transition state, producing chiral hydroxylamines with up to 99 % yield and >99 % ee. The practical viability of this methodology was underscored by gram-scale catalytic reactions and subsequent transformations. Furthermore, mechanistic investigations and DFT calculations were also conducted to elucidate the origin of enantioselectivity.

6.
Angew Chem Int Ed Engl ; 63(22): e202403668, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38462892

RESUMO

The electrolyte chemistry is crucially important for promoting the practical application of lithium metal batteries (LMBs). Here, we demonstrate for the first time that 1,3-dimethylimidazolium dimethyl phosphate (DIDP) and trimethylsilyl trifluoroacetate (TMSF) can undergo in situ transesterification in carbonate electrolyte to generate dimethyl trimethylsilyl phosphate (DTMSP) and 1,3-dimethylimidazolium trifluoroacetate (DITFA) as multifunctional additives for LMBs. H2O and HF can be removed by the Si-O group in DTMSP to improve the moisture resistance of electrolyte and the stability of cathode. Furthermore, the dissolution of lithium nitrate (LiNO3) in carbonate electrolyte can be promoted by the trifluoroacetate anion (TFA-) in DITFA, thereby optimizing the solvation structure and transport kinetics of Li+. More importantly, both DTMSP and DITFA tend to preferential redox decomposition due to the low lowest unoccupied molecular orbital (LUMO) and high highest occupied molecular orbital (HOMO). Consequently, a thin and robust layer rich in P/N/Si on the cathode and an inorganic-rich layer (e.g. Li3N/Li3P) on the anode can be constructed and superior electrochemical performances are achieved. This artificial transesterification strategy to introduce favorable additives paves an efficient and ingenious route to high-performance electrolyte for LMBs.

7.
Artigo em Inglês | MEDLINE | ID: mdl-37589186

RESUMO

A Gram-negative, rod-shaped and aerobic bacterial strain B3.7T, was isolated from the sediment of Zhairuo Island, Zhoushan city, Zhejiang Province, PR China. Maximum growth of strain B3.7T was observed at 30 °C when cultured in a medium containing 0.5 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences demonstrated that strain B3.7T belonged to the genus Shinella; it showed the highest sequence similarity of 98.47 % to Shinella kummerowiae CCBAU 25048T. The average nucleotide identity and digital DNA-DNA hybridization values between strain B3.7T and its reference strains were 82.9-84.2 % and 26.1-27.3 %, respectively. Chemotaxonomic analysis indicated that the sole respiratory quinone was Q-10 and the predominant cellular fatty acids were C19 : 0 cyclo ω8c, C16 : 0, C18 : 1 ω7c 11-methyl and summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c). The polar lipid profile was composed of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, three unidentified phospholipids and two unidentified aminolipids. Collectively, strain B3.7T can be considered to represent a novel species, for which the name Shinella sedimenti sp. nov. is proposed. The type strain is B3.7T (=MCCC 1K07163T=LMG 32559T).


Assuntos
Ácidos Graxos , Ácidos Graxos/química , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Composição de Bases , China
8.
Antonie Van Leeuwenhoek ; 116(2): 97-107, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36222940

RESUMO

A novel bacterium designated A3.4T was isolated from the beach sediment of Zhairuo Island, which is located in the East China Sea. Strain A3.4T was found to be Gram-stain negative, cream coloured, rod-shaped, aerobic and motile via a single monopolar flagellum. The isolate grows at 20-37 °C (optimum 25-30 °C), at pH 6.0-8.0 (optimum pH 7.0-8.0), and in the presence of 0-5.0% (w/v) NaCl (optimum 0.5-1%). A3.4T has catalase and oxidase activity. The predominant fatty acids (≥ 10%) of the strain were identified as C16:0, summed feature 3 (C16:1 ω7c /C16:1 ω6c) and summed feature 8 (C18:1 ω7c /C18:1 ω6c). Q-9 was identified as the major isoprenoid quinone, with trace levels of Q-8 present. The major polar lipids were identified as diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol. The draft genome size is 3.55 Mb, with a DNA G + C content of 57.7 mol%. Analysis of the 16S rRNA gene sequence of strain A3.4T indicates that it belongs to the genus Atopomonas and shares high sequence similarity with Atopomonas hussainii JCM 19513T (97.60%). This classification was also supported by phylogenetic analysis using rpoB and several core genes. The genome of strain A3.4T shows an average nucleotide identity of 82.3%, an amino acid identity of 83.0%, and a digital DNA-DNA hybridization value of 22.1% with A. hussainii. In addition, 20 conserved signature indels (CSIs) were identified to be specific for A3.4T and A. hussainii, demonstrating that the strain A3.4T is closely related to A. hussainii rather than other species of family Pseudomonadaceae. Hundreds of unique genes were identified in the genomes of A3.4T and A. hussainii, which may underly multiple phenotypic differences between these strains. Based on phenotypic, chemotaxonomic, phylogenetic, and genomic investigations, strain A3.4T is concluded to represent a novel species of the genus Atopomonas, for which the name Atopomonas sediminilitoris sp. nov. is proposed. The type strain is A3.4T (= LMG 32563T = MCCC 1K07166T).


Assuntos
Ácidos Graxos , Fosfolipídeos , Fosfolipídeos/análise , Filogenia , RNA Ribossômico 16S/genética , Técnicas de Tipagem Bacteriana , Ácidos Graxos/análise , DNA , China , DNA Bacteriano/genética , DNA Bacteriano/química , Análise de Sequência de DNA
9.
Curr Microbiol ; 80(4): 113, 2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36823402

RESUMO

A novel Gram-staining negative, aerobic, rod-shaped bacterium, designated strain YIM DDC1T, was isolated from an estuary sediment sample of Dongda River flowing into Dianchi lake in Yunnan, southwest China. The strain displayed growth at 10-40 °C (optimum of 28 °C), pH 5.0-9.0 (optimum of 7.0-8.0) and in presence of 0-3% (w/v) NaCl (optimum of 0-1%). Strain YIM DDC1T comprised diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine and two unidentified aminolipids as the predominant polar lipids; the ubiquinone 10 as the major respiratory quinone; and summed feature 8 (C18:1ω6c and/or C18:1ω7c), summed feature 3 (C16:1ω7c and/or C16:1ω6c) and C18:1 2-OH as the major cellular fatty acids. Analysis of 16S rRNA showed that YIM DDC1T represents a member of the genus Azospirillum, and was closely related to A. brasilense ATCC 29145 T (98.9%), A. baldaniorum Sp245T (98.2%), A. argentinense Az39T (98.2%) and A. formosense CC-Nfb-7 T (98.2%). The draft genome size was 7.15 Mbp with a 68.4% G + C content. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between strain YIM DDC1T and the aforementioned closely related strains exhibited similarity in the range of 93.8-93.5% and 53.7-52.7%, respectively. nif gene cluster (nifHDK) and denitrification genes ((napA, nirS, nirK, norBC and nosZ) detected in the genome indicated its potential nitrogen fixation and full-fledged denitrifying function. Based on combined genotypic and phenotypic data, strain YIM DDC1T represents a novel species of the genus Azospirillum, for which the name Azospirillum aestuarii sp. nov. is proposed. The type strain is YIM DDC1T (= KCTC 42887 T = CGMCC 1.17325 T).


Assuntos
Azospirillum , Fosfolipídeos , Fosfolipídeos/química , Rios/microbiologia , Azospirillum/genética , Estuários , RNA Ribossômico 16S/genética , China , Ácidos Graxos/química , DNA , Filogenia , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Análise de Sequência de DNA
10.
BMC Public Health ; 23(1): 2378, 2023 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-38037037

RESUMO

BACKGROUND: Evidence on the role of physical activity (PA) on healthcare utilization and expenditure is limited in China. We aimed to examine the association between the total physical activity (TPA) per week, healthcare service use and expenditure. METHODS: We extracted the data from China Health and Retirement Longitudinal Study (CHARLS) 2011, 2013, and 2015. Participants more than 50 years old who completed the follow-up for the three waves were enrolled. We converted the volume of vigorous physical activity (VPA) into an equivalent volume of moderate physical activity (MPA) and calculated the TPA per week for each participant. 12,927 of the 17,708 participants in CHARLS were included in our analysis. More than one-third of participants over 50 years old never participate in any moderate or intensity activity, and the median of self-reported moderate or intensity PA was about 525 (IQR 0-1680) MET-minutes per week in 2015. RESULTS: Compared to inactive subjects, the highest level of TPA was significantly related to the decreased risk number of inpatient visits (IRR: 0.58; 95% CI:0.50-0.67, p < 0.001), inpatient hospital days (IRR: 0.60; 95% CI: 0.42-0.84, p < 0.01), healthcare expenditure (IRR: 0.71; 95% CI: 0.65-0.79, p < 0.001) and catastrophic health expenditures (OR: 0.57; 95% CI: 0.45-0.72, p < 0.001) after adjusting for covariates. CONCLUSIONS: Engaging in moderate-to-vigorous PA may drive a potential decrease in healthcare utilization, healthcare expenditure and household financial risk with a dose-response relationship in China, and some possible policy implications in public health may be considered to promote exercise in the middle-aged and elderly to reduce the medical burden on individuals and healthcare systems.


Assuntos
Exercício Físico , Gastos em Saúde , Aceitação pelo Paciente de Cuidados de Saúde , Idoso , Humanos , Pessoa de Meia-Idade , China , Estudos Longitudinais , Aposentadoria , Saúde Pública
11.
Adv Physiol Educ ; 47(2): 259-264, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36861765

RESUMO

Collaborative testing has been demonstrated the ability to improve students' performance, enhance students' learning, and aid in knowledge retention in many different courses. However, this examination mode lacks the process of teacher feedback. Herein, a short teacher feedback from was added immediately after the collaborative testing to improve the students' performance. A parasitology class of 121 undergraduates was randomized into two groups: group A and group B. Collaborative testing was carried out at the end of theoretical teaching. During the test, students would first answer questions as individuals for 20 minutes. Then, students from group A answered the same questions in groups (5 students in each group) for 20 minutes, while the group-testing duration was only 15 minutes in group B. Immediately after the group testing, teachers conducted a 5-minute feedback about the morphology identification according to the analysis of the answers by group B. Four weeks later, a final test was conducted in an individual test. The total scores and scores for each examination content were analyzed. The results showed that there was no significant difference in the final exam scores between both groups (t = -1.278, P = 0.204). However, the morphological and diagnostic test results of the final examination in group B were significantly higher than those of the midterm examination, while there was no significant change in group A (t = 4.333, P = 0.051). The results confirmed that the teacher feedback after the collaborative testing can effectively make up for the students' knowledge gaps.NEW & NOTEWORTHY This study found that collaborative group testing is helpful for teachers to grasp students' knowledge gaps more easily and the teacher feedback after the collaborative group testing can effectively make up for the knowledge gaps of students.


Assuntos
Estudantes , Humanos , Retroalimentação
12.
Sensors (Basel) ; 23(23)2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-38067779

RESUMO

Modern embedded systems have achieved relatively high processing power. They can be used for edge computing and computer vision, where data are collected and processed locally, without the need for network communication for decision-making and data analysis purposes. Face detection, face recognition, and pose detection algorithms can be executed with acceptable performance on embedded systems and are used for home security and monitoring. However, popular machine learning frameworks, such as MediaPipe, require relatively high usage of CPU while running, even when idle with no subject in the scene. Combined with the still present false detections, this wastes CPU time, elevates the power consumption and overall system temperature, and generates unnecessary data. In this study, a low-cost low-resolution infrared thermal sensor array was used to control the execution of MediaPipe's pose detection algorithm using single-board computers, which only runs when the thermal camera detects a possible subject in its field of view. A lightweight algorithm with several filtering layers was developed, which allowed the effective detection and isolation of a person in the thermal image. The resulting hybrid computer vision proved effective in reducing the average CPU workload, especially in environments with low activity, almost eliminating MediaPipe's false detections, and reaching up to 30% power saving in the best-case scenario.


Assuntos
Algoritmos , Carga de Trabalho , Humanos , Computadores , Aprendizado de Máquina
13.
Angew Chem Int Ed Engl ; 62(40): e202310577, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37578644

RESUMO

Aqueous rechargeable zinc-ion batteries (ARZBs) are impeded by the mutual problems of unstable cathode, electrolyte parasitic reactions, and dendritic growth of zinc (Zn) anode. Herein, a triple-functional strategy by introducing the tetramethylene sulfone (TMS) to form a hydrated eutectic electrolyte is reported to ameliorate these issues. The activity of H2 O is inhibited by reconstructing hydrogen bonds due to the strong interaction between TMS and H2 O. Meanwhile, the preferentially adsorbed TMS on the Zn surface increases the thickness of double electric layer (EDL) structure, which provides a shielding buffer layer to suppress dendrite growth. Interestingly, TMS modulates the primary solvation shell of Zn2+ ultimately to achieve a novel solvent co-intercalation ((Zn-TMS)2+ ) mechanism, and the intercalated TMS works as a "pillar" that provides more zincophilic sites and stabilizes the structure of cathode (NH4 V4 O10 , (NVO)). Consequently, the Zn||NVO battery exhibits a remarkably high specific capacity of 515.6 mAh g-1 at a low current density of 0.2 A g-1 for over 40 days. This multi-functional electrolytes and solvent co-intercalation mechanism will significantly propel the practical development of aqueous batteries.

14.
Angew Chem Int Ed Engl ; 62(5): e202215324, 2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36446732

RESUMO

The rampant dendrites and hydrogen evolution reaction (HER) resulting from the turbulent interfacial evolution at the anode/electrolyte are the main culprits of short lifespan and low Coulombic efficiency of Zn metal batteries. In this work, a versatile protective coating with excellent zincophilic and amphoteric features is constructed on the surface of Zn metal (ZP@Zn) as dendrite-free anodes. This kind of protective coating possesses the advantages of reversible proton storage and rapid desolvation kinetics, thereby mitigating the HER and facilitating homogeneous nucleation concomitantly. Furthermore, the space charge polarization effect promotes charge redistribution to achieve uniform Zn deposition. Accordingly, the ZP@Zn symmetric cell manifests excellent reversibility at an ultrahigh cumulative plating capacity of 4700 mAh cm-2 and stable cycling at 80 % depth of discharge (DOD). The ZP@Zn//V6 O13 pouch cell also reveals superior cycling stability with a high capacity of 326.6 mAh g-1 .

15.
Angew Chem Int Ed Engl ; 62(25): e202218672, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37083044

RESUMO

With ever-increasing pursuit for high-value output in recycling spent lithium-ion batteries (LIBs), traditional recycling methods of cathodes tend to be obsolete because of the complicated procedures. Herein, we first upcycle spent polycrystal LiNi0.88 Co0.095 Al0.025 O2 (S-NCA) to high value-added single-crystalline and Li-rich cathode materials through a simple but feasible LiOH-Na2 SO4 eutectic molten salt strategy. The in situ X-ray diffraction technique and a series of paratactic experiments record the evolution process of upcycling and prove that excessive Li occupies the transition metal (TM) layers. Beneficial from the single-crystalline and Li-rich nature, the regenerated NCA (R-NCA) exhibits remarkably enhanced electrochemical performances in terms of long-term cyclability, high-rate performance and low polarization. This approach can also be successfully extended to other cathode materials e.g., LiNix Coy Mnz O2 (NCM) and mixed spent NCAs with varied degree of Li loss.


Assuntos
Lítio , Cloreto de Sódio , Fontes de Energia Elétrica , Eletrodos , Íons
16.
J Am Chem Soc ; 144(39): 17763-17768, 2022 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-36166275

RESUMO

Due to their low reactivity, difficult enantiocontrol, and proneness to N-O bond cleavage, the catalytic asymmetric hydrogenation of oximes to hydroxylamines has remained a significant challenge. Herein, a Lewis and Brønsted acid cooperation strategy was established for the asymmetric hydrogenation of oximes, providing the corresponding hydroxylamines with up to 95% yield and up to 96% ee. Addition of Lewis and Brønsted acid was crucial to obtain high conversion and enantioselectivity. Mechanistic investigations indicates that the thiourea fragment of the ligand, Lewis acid (In(OTf)3 or Zn(OAc)2), as well as the Brønsted acid (l-CSA) played vital roles in the control of reactivity and enantioselectivity of the reaction. In addition, the synthetic elaboration of this transformation was demonstrated by gram scale experiment with retention of the yield and enantioselectivity.


Assuntos
Ácidos de Lewis , Oximas , Hidrogenação , Ligantes , Estereoisomerismo , Tioureia
17.
Small ; 18(43): e2106719, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35182009

RESUMO

Recycling spent lithium-ion batteries (LIBs) is an urgent task in view of the resource shortage and environmental concerns. Here, a facile ternary molten salt approach is presented for efficiently regenerating the LiNi0.5 Co0.2 Mn0.3 O2 (NCM523) cathode of spent LIBs. Such an approach involves the treatment of spent cathode powder in the ternary molten salt at a moderate temperature (400 °C) and subsequent annealing in oxygen. The Li loss and degraded phases in spent NCM that cause the capacity decay can be fully remedied after the regeneration process. As a result, the regenerated cathode delivers a reversible capacity of 160 mAh g-1 at 0.5 C with retention of 93.7% after 100 cycles and maintains a high capacity of 132 mAh g-1 at a high rate of 5 C. The electrochemical performance of regenerated NCM cathode is compared favorably to the fresh NCM cathode, which demonstrates the feasibility of the molten salt approach to directly regenerate spent NCM cathode.

18.
Microvasc Res ; 139: 104260, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34624308

RESUMO

OBJECTIVES: To explore whether minimally modified low-density lipoprotein (mmLDL) upregulates mesenteric arterial 5-hydroxytryptamine 1B (5-HT1B) receptor expression by activating the JAK2/STAT3 signaling pathway. METHODS: Mice were randomly divided into the following groups: the normal saline (NS), LDL, mmLDL, mmLDL+galiellactone (GL, a JAK2/STAT3 pathway inhibitor), and mmLDL+DMSO groups. The dose-response curve of mesenteric arterial ring constriction after administration of 5-carboxamidotryptamine (5-CT), an agonist of 5-HT1B, was recorded with a microvascular tensiometer. JAK2, p-JAK2, STAT3, p-STAT3, and 5-HT1B receptor protein expression levels were determined by Western blotting. 5-HT1B receptor mRNA levels were measured by RT-PCR. 5-HT1B receptor protein expression was determined by immunofluorescence. RESULTS: Injection of mmLDL into the tail vein significantly increased the contractile dose-response curve after 5-CT stimulation, as the Emax was 82.15 ±â€¯6.15% in the NS group and 171.88 ±â€¯5.78% in the mmLDL group (P < 0.01); significantly elevated 5-HT1B receptor mRNA and protein expression levels; and significantly increased p-JAK2 and p-STAT3 protein expression levels. After intraperitoneal injection of GL, the vasoconstrictive response was significantly reduced compared with that in the mmLDL group, as the Emax was decreased to 97.14 ±â€¯1.20% (P < 0.01); 5-HT1B receptor mRNA and protein expression levels were significantly reduced; STAT3 phosphorylation and p-JAK2 and p-STAT3 protein expression were not significantly changed; and 5-HT1B receptor expression was altered via inhibition of p-STAT3 binding to DNA, which suppressed transcription. CONCLUSIONS: mmLDL can upregulate 5-HT1B receptor expression in mouse mesenteric arteries by activating the JAK2/STAT3 signaling pathway.


Assuntos
Janus Quinase 2/metabolismo , Lipoproteínas LDL/farmacologia , Artérias Mesentéricas/efeitos dos fármacos , Receptor 5-HT1B de Serotonina/metabolismo , Fator de Transcrição STAT3/metabolismo , Vasoconstrição/efeitos dos fármacos , Animais , Ativação Enzimática , Feminino , Masculino , Artérias Mesentéricas/enzimologia , Camundongos , Fosforilação , Receptor 5-HT1B de Serotonina/genética , Transdução de Sinais , Regulação para Cima
19.
Arch Microbiol ; 204(7): 430, 2022 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-35759057

RESUMO

A Gram-negative, aerobic, non-motile, oxidase-positive, catalase-positive, methyl red-positive, and lipase-negative bacterium, designated A5.8T, was isolated from beach sediment of Zhairuo Island located in the East China Sea. Growth occurred at 10-40 °C (optimum, 30 °C), pH 5.5-9.5 (optimum, 7.5), and 0-2% NaCl (optimum, 1.5%). Based on 16S rRNA gene sequence analysis, strain A5.8T belongs to the genus Ancylobacter, sharing the highest similarity with Ancylobacter aquaticus JCM 20518T (98.0%). Its polar lipids mainly consist of phosphatidylethanolamine (PE) and phosphatidylcholine (PC). The predominant fatty acids are summed feature 8 (C18:1ω7c and/or C18:1ω6c, 91.0%), and the major respiratory quinone is Q-10. The DNA G + C content is 67.2 mol%. Based on above analysis, as well as digital DNA-DNA hybridization (22.5-22.9%) and average nucleotide identity (83.0-83.6%) of strain A5.8T with reference type strains of the genus Ancylobacter, strain A5.8T was suggested to represent a novel species of the genus Ancylobacter, for which the name Ancylobacter gelatini sp. nov. is proposed. The type strain is A5.8T (= MCCC 1K07167T = LMG 32566T).


Assuntos
Alphaproteobacteria , Filogenia , Alphaproteobacteria/classificação , Alphaproteobacteria/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Sedimentos Geológicos/microbiologia , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/análogos & derivados , Ubiquinona/química
20.
Int J Syst Evol Microbiol ; 72(11)2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36748468

RESUMO

A Gram-stain-negative, aerobic, non-motile, non-haemolytic, oxidase-negative, catalase-positive bacillus strain (A3.8T) was isolated from beach sediment from Zhairuo Island, PR China. The strain grew at pH 6.0-9.0 (optimum, 7.0), with 0-4.5 % NaCl (optimum, 2 %) and at 10-35 °C (optimum, 30 °C). Its whole-genome sequence was 2.5 Mb in size, with a DNA G+C content of 41.6 mol%. On the basis of the results of core genome phylogenetic analysis, A3.8T represents a separate branch within the clade formed by five species of the genus Acinetobacter with 'Acinetobacter marinus' as the most closely related species. The average nucleotide identity compared with the closely related species of the genus Acinetobacter was below 83.66 % and digital DNA-DNA hybridization values were less than 28.80 %. The predominant fatty acids included C18 : 1ω9c, C16 : 0 and summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c). Q-9 was the major respiratory quinone. The polar lipids are mainly composed of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, two phospholipids, an aminolipid and four unknown lipids. A3.8T cannot assimilate dl-lactate and weakly utilizes l-glutamate, l-leucine, l-phenylalanine and l-tartrate, which distinguishes it from other species of the genus Acinetobacter. On the basis of the genotype, phenotype and biochemical data, strain A3.8T represents a novel species of the genus Acinetobacter, for which the name Acinetobacter sedimenti sp. nov. is proposed. The type strain is A3.8T (=MCCC 1K07161T=LMG 32568T).


Assuntos
Acinetobacter , Ácidos Graxos , Ácidos Graxos/química , Filogenia , Composição de Bases , DNA Bacteriano/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Técnicas de Tipagem Bacteriana , Fosfolipídeos/química , China
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