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1.
J Exp Biol ; 227(19)2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39284689

RESUMO

Flight behaviours of birds have been extensively studied from different angles such as their kinematics, aerodynamics and, more generally, their migration patterns. Nevertheless, much is still unknown about the daily foraging flight activity and behaviour of breeding birds, and potential differences among males and females. The recent development of miniaturized accelerometers allows us a glimpse into the daily life of a songbird. Here, we tagged 13 male and 13 female pied flycatchers (Ficedula hypoleuca) with accelerometers and used machine learning approaches to analyse their flight activity and effort during the chick rearing period. We found that during 2 h of foraging, chick-rearing pied flycatchers were flying on average 13.7% of the time. Almost all flights (>99%) were short flights lasting less than 10 s. Flight activity changed throughout the day and was highest in the morning and lowest in the early afternoon. Male pied flycatchers had lower wing loading than females, and in-flight accelerations were inversely correlated with wing loading. Despite this, we found no significant differences in flight duration and intensity between sexes. This suggests that males possess a higher potential flight performance, which they did not fully utilize during foraging flights.


Assuntos
Acelerometria , Voo Animal , Aprendizado de Máquina , Animais , Voo Animal/fisiologia , Masculino , Feminino , Aves Canoras/fisiologia , Fenômenos Biomecânicos
2.
Yi Chuan ; 46(3): 256-262, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38632103

RESUMO

Hepatocyte nuclear factor 1α (HNF1α) is a transcription factor that is crucial for the regulation to maintain the function of pancreatic ß-cell, hepatic lipid metabolism, and other processes. Mature-onset diabetes of the young type 3 is a monogenic form of diabetes caused by HNF1α mutations. Although several mutation sites have been reported, the specific mechanisms remain unclear, such hot-spot mutation as the P291fsinsC mutation and the P112L mutation and so on. In preliminary studies, we discovered one MODY3 patient carrying a mutation at the c.493T>C locus of the HNF1α gene. In this study, we analyzed the pathogenic of the mutation sites by using the Mutation Surveyor software and constructed the eukaryotic expression plasmids of the wild-type and mutant type of HNF1α to detect variations in the expression levels and stability of HNF1α protein by using Western blot. The analyses of the Mutation Surveyor software showed that the c.493T>C site mutation may be pathogenic gene and the results of Western blot showed that both the amount and stability of HNF1α protein expressed by the mutation type plasmid were reduced significantly compared to those by the wild type plasmid (P<0.05). This study suggests that the c.493T>C (p.Trp165Arg) mutation dramatically impacts HNF1α expression, which might be responsible for the development of the disease and offers fresh perspectives for the following in-depth exploration of MODY3's molecular pathogenic process.


Assuntos
Diabetes Mellitus Tipo 2 , Fator 1-alfa Nuclear de Hepatócito , Células Secretoras de Insulina , Humanos , Diabetes Mellitus Tipo 2/genética , Fator 1-alfa Nuclear de Hepatócito/genética , Fator 1-alfa Nuclear de Hepatócito/metabolismo , Células Secretoras de Insulina/metabolismo , Mutação
3.
Angew Chem Int Ed Engl ; : e202417435, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39385458

RESUMO

Photocatalytic reduction of diluted CO2 from anthropogenic sources holds tremendous potential for achieving carbon neutrality, while the huge barrier to forming *COOH key intermediate considerably limits catalytic effectiveness. Herein, via coordination engineering of atomically scattered Ni sites in conductive metal-organic frameworks (CMOFs), we propose a facile strategy for tailoring the d­band center of metal active sites towards high-efficiency photoreduction of diluted CO2. Under visible-light irradiation in pure CO2, CMOFs with Ni-O4 sites (Ni-O4 CMOFs) exhibits an outstanding rate for CO generation of 13.3 µmol h-1 with a selectivity of 94.5%, which is almost double that of its isostructural counterpart with traditional Ni-N4 sites (Ni-N4 CMOFs), outperforming most reported systems under comparable conditions. Interestingly, in simulated flue gas, the CO selectivity of Ni-N4 CMOFs decreases significantly while that of Ni-O4 CMOFs is mostly unchanged, signifying the supremacy for Ni-O4 CMOFs in leveraging anthropogenic diluted CO2. In-situ spectroscopy and density functional theory (DFT) investigations demonstrate that O coordination can move the center of the Ni sites' d-band closer to the Fermi level, benefiting the generation of *COOH key intermediate as well as the desorption of *CO and hence leading to significantly boosted activity and selectivity for CO2-to-CO photoreduction.

4.
Small ; 19(47): e2303185, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37490550

RESUMO

Sn-based electrocatalysts have great economic potential in the reduction of CO2 to HCOOH, while they still suffer from low current density, dissatisfactory selectivity, and poor stability. Inspired by electronic modification engineering, boron-doped SnO2 nanospheres (B-SnO2 ) are successfully synthesized to achieve high-efficiency CO2 reduction reaction (CO2 RR). It is found that the introduction of boron dopants can increase the number of active sites and facilitate the formation of the electron-rich Sn sites in its structure, thus enhancing the activation of CO2 molecules and reducing the energy barrier of *OCHO intermediates on the SnO2 surface. Thus, the B-doped SnO2 electrocatalyst exhibits a remarkable FEHCOOH above 90% within a broad potential window of -0.7 to -1.3 V versus reversible hydrogen electrode (RHE) (600 mV) and obtains the maximum value of 95.1% (the partial current density of HCOOH is 42.35 mA cm-2 ) at -1 V versus RHE. In conclusion, this work provides a novel strategy for optimizing the intrinsic properties of electrocatalysts for CO2 RR by the method of tuning the electronic structure.

5.
Int J Mol Sci ; 24(9)2023 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-37175877

RESUMO

Salmonella enterica serovar typhimurium (S. Typhimurium) is a common Gram-negative foodborne pathogenic bacterium that causes gastrointestinal disease in humans and animals. It is well known that adhesins and invasins play crucial roles in the infection mechanism of S. Typhimurium. S. Typhimurium STM0306 has been denoted as a putative protein and its functions have rarely been reported. In this study, we constructed the STM0306 gene mutant strain of S. Typhimurium and purified the recombinant STM0306 from Escherichia coli. Deletion of the STM0306 gene resulted in reduced adhesion and invasion of S. Typhimurium to IPEC-J2, Caco-2, and RAW264.7 cells. In addition, STM0306 could bind to intestinal epithelial cells and induced F-actin modulation in IPEC-J2 cells. Furthermore, we found that STM0306 activated the nuclear factor kappa B (NF-κB) signaling pathway and increased the mRNA expression of pro-inflammatory cytokines such as IL-1ß, TNF-α, as well as chemokine CXCL2, thus resulting in cellular inflammation in host cells. In vivo, the deletion of the STM0306 gene led to reduced pathogenicity of S. Typhimurium, as evidenced by lower fecal bacterial counts and reduced body weight loss in S. Typhimurium infected mice. In conclusion, the STM0306 of S. Typhimurium is an important adhesin/invasin involved in the pathogenic process and cellular inflammation of the host.


Assuntos
Adesinas Bacterianas , Salmonella typhimurium , Humanos , Animais , Camundongos , Salmonella typhimurium/metabolismo , Sorogrupo , Células CACO-2 , Adesinas Bacterianas/genética , Adesinas Bacterianas/metabolismo , Inflamação/genética
6.
Small ; 16(38): e2002985, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32812346

RESUMO

Direct photoconversion of low-concentration CO2 into a widely tunable syngas (i.e., CO/H2 mixture) provides a feasible outlet for the high value-added utilization of anthropogenic CO2 . However, in the low-concentration CO2 photoreduction system, it remains a huge challenge to screen appropriate catalysts for efficient CO and H2 production, respectively, and provide a facile parameter to tune the CO/H2 ratio in a wide range. Herein, by engineering the metal sites on the covalent organic frameworks matrix, low-concentration CO2 can be efficiently photoconverted into tunable syngas, whose CO/H2 ratio (1:19-9:1) is obviously wider than reported systems. Experiments and density functional theory calculations indicate that Fe sites serve as the H2 evolution sites due to the much stronger binding affinity to H2 O, while Ni sites act as the CO production sites for the higher affinity to CO2 . Notably, the widely tunable syngas can also be produced over other Fe/Ni-based bimetal catalysts, regardless of their structures and supporting materials, confirming the significant role of the metal sites in regulating the selectivity of CO2 photoreduction and providing a modular design strategy for syngas production.

7.
Nano Lett ; 19(3): 1860-1866, 2019 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-30676748

RESUMO

Sn-based anode materials have become potential substitutes for commercial graphite anode due to their high specific capacity and good safety. In this paper, ultrafine Sn nanoparticles embedded in nitrogen and phosphorus codoped porous carbon nanorods (Sn@C) are obtained by carbonizing bacteria that adsorb the Sn electroplating sludge extracting solution. The as-prepared Sn@C rod-shaped composite exhibits superior electrochemical Li-storage performances, such as a reversible capacity of approximate 560 mAh/g at 1 A/g and an ultralong cycle life exceeding 1500 cycles, with approximately no capacity decay. The ultrastable structure of the Sn@C was revealed using in situ transmission electron microscope at the nanoscale and indicated that the Sn@C composite could restrict the volume expansion of Sn nanoparticles during the lithiation/delithiation cycles. This work provides a new insight into addressing the electroplating sludge and designing novel lithium ion battery anodes.

8.
Anim Nutr ; 14: 334-342, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37635927

RESUMO

This study aimed to investigate the potential mitigating effects of N-acyl homoserine lactonase (AHLase) on the virulence of Salmonella typhimurium and its induction of intestinal damages in broilers. In vitro study was firstly conducted to examine if AHLase treatment could attenuate the virulence of S. typhimurium. Then, an in vivo experiment was performed by allocating 240 broiler chicks at 1 d old into 3 groups (8 replicates per group): negative control (NC), positive control (PC), and PC supplemented with 10,000 U/kg AHLase. All chicks except those in NC were orally challenged by S. typhimurium from 8 to 10 d of age. Parameters were measured on d 11 and 21. The results showed that treatment with 1 U/mL AHLase suppressed the biofilm-forming ability (including biofilm biomass, extracellular DNA secretion and biofilm formation-related gene expression), together with swarming motility and adhesive capacity of S. typhimurium. Supplemental 10,000 U/kg AHLase counteracted S. typhimurium-induced impairments (P < 0.05) in broiler growth performance (including final body weight, average daily gain and average daily feed intake) during either 1-11 d or 12-21 d, and increases (P < 0.05) in the indexes of liver, spleen and bursa of Fabricius on d 11, together with reductions (P < 0.05) in ileal villus height and its ratio to crypt depth on both d 11 and 21. AHLase addition also normalized the increased (P < 0.05) mRNA expression of ileal occludin on both d 11 and 21 in S. typhimurium-challenged broilers. However, neither S. typhimurium challenge nor AHLase addition altered (P > 0.05) serum diamine oxidase activity of broilers. Noticeably, S. typhimurium challenge caused little change in the mRNA expression of ileal inflammatory cytokines except for an increase (P < 0.05) in interleukin-8 expression on d 11, whereas AHLase addition normalized (P < 0.05) this change. In conclusion, AHLase treatment could attenuate the virulence and pathogenicity of S. typhimurium, thus contributing to alleviate S. typhimurium-induced growth retardation and intestinal damages in broilers.

9.
ACS Nano ; 16(11): 19210-19219, 2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36255287

RESUMO

Using the electrochemical CO2 reduction reaction (CO2RR) with Cu-based electrocatalysts to achieve carbon-neutral cycles remains a significant challenge because of its low selectivity and poor stability. Modulating the surface electron distribution by defects engineering or doping can effectively improve CO2RR performance. Herein, we synthesize the electrocatalyst of Vo-CuO(Sn) nanosheets containing oxygen vacancies and Sn dopants for application in CO2RR-to-CO. Density functional theory calculations confirm that the incorporation of oxygen vacancies and Sn atoms substantially reduces the energy barrier for *COOH and *CO intermediate formation, which results in the high efficiency, low overpotential, and superior stability of the CO2RR to CO conversion. This electrocatalyst possesses a high Faraday efficiency (FE) of 99.9% for CO at a low overpotential of 420 mV and a partial current density of up to 35.22 mA cm-2 at -1.03 V versus reversible hydrogen electrode (RHE). The FECO of Vo-CuO(Sn) could retain over 95% within a wide potential area from -0.48 to -0.93 V versus RHE. Moreover, we obtain long-term stability for more than 180 h with only a slight decay in its activity. Therefore, this work provides an effective route for designing environmentally friendly electrocatalysts to improve the selectivity and stability of the CO2RR to CO conversion.

10.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(3): 865-868, 2021 Jun.
Artigo em Zh | MEDLINE | ID: mdl-34105485

RESUMO

OBJECTIVE: To understand the genotypes and distribution characteristics of thalassemia in Baise, Guangxi Zhuang Autonomous Region, to provide references for the prevention and diagnosis of thalassemia in the region and improve the quality of eugenics. METHODS: 3 482 pregnant women and their spouses from January 2019 to August 2019 in Baise Maternal and Child Health Hospital for prenatal genetic diagnosis were selected, α, ß- thalassemia genes were detected by Gap-PCR, PCR and DNA reverse dot hybridization, cases carrying thalassemia gene were confirmed and statistical analyzed. RESULTS: 2 260 samples (64.90%) carrying thalassemia gene were found, among which 1 459 cases (64.56%) were diagnosed as α- thalassemia, 617 cases (27.30%) as ß- thalassemia, 184 cases (8.14%) as α complex ß- thalassemia. Among 1 459 α- thalassemia genes, --SEA /αα(637 cases, 43.66%), -α3.7 /αα (306 cases, 20.97%), -αCS /αα(143 cases, 9.80%), -α4.2 /αα(124 cases, 8.50%) and -αWS /αα(77 cases, 5.27%) were the most common, while among 617 ß- thalassemia genes, CD17 (229 cases, 37.12%), CD41-42 (213 cases, 34.52%), IVS-I-1 (41 cases, 6.65%), ßE (38 cases, 6.16%) and CD71-72 (34 cases, 5.51%) were the most common. And --SEA /αα/ CD17 (24 cases, 13.04%), -α4.2 /αα/ CD17 (13 cases, 7.07%), -α3.7 /αα/ CD41-42 (12 cases, 6.52% ) and --SEA /αα/ CD41-42 (12 cases, 6.52%) were mainly found in 184 cases of α complex ß - thalassemia. CONCLUSION: Genotyes of thalassemia in Baise, Guangxi Zhuang Autonomous Region are complex and diverse. The prenatal screening and diagnosis of thalassemia in the region should be strengthened in accordance with the characteristics of genetypes in the region, in order to reduce birth defects and improve eugenics quality.


Assuntos
Talassemia alfa , Talassemia beta , Criança , China , Feminino , Genótipo , Humanos , Mutação , Gravidez , Diagnóstico Pré-Natal , Talassemia alfa/diagnóstico , Talassemia alfa/epidemiologia , Talassemia alfa/genética , Talassemia beta/diagnóstico , Talassemia beta/genética
11.
Front Cell Infect Microbiol ; 11: 758898, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34869065

RESUMO

Salmonella Typhimurium is a common pathogen infecting the gastrointestinal tract of humans and animals, causing host gastroenteritis and typhoid fever. Heat shock protein (HtpG) as a molecular chaperone is involved in the various cellular processes of bacteria, especially under environmental stress. However, the potential association of HtpG with S. Typhimurium infection remains unknown. In this study, we clarified that HtpG could also play a role as an effector in S. Typhimurium infection. RNA-seq indicated that the flagellar assembly pathway, infection pathway, and chemotaxis pathway genes of S. Typhimurium were downregulated after the mutation of HtpG, which resulted in compromises of S. Typhimurium motility, biofilm formation, adhesion, invasion, and inflammation-inducing ability. In addition, HtpG recombinant protein was capable of promoting the proliferation of S. Typhimurium in host cells and the resultant inflammation. Collectively, our results illustrated an important role of HtpG in S. Typhimurium infection.


Assuntos
Proteínas de Choque Térmico , Salmonella typhimurium , Animais , Proteínas de Bactérias/genética , Proliferação de Células , Humanos , Salmonella typhimurium/genética
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