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1.
Vet Res ; 55(1): 37, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38532498

RESUMO

In the last decade, prophages that possess the ability of lysogenic transformation have become increasingly significant. Their transfer and subsequent activity in the host have a significant impact on the evolution of bacteria. Here, we investigate the role of prophage phi456 with high spontaneous induction in the bacterial genome of Avian pathogenic Escherichia coli (APEC) DE456. The phage particles, phi456, that were released from DE456 were isolated, purified, and sequenced. Additionally, phage particles were no longer observed either during normal growth or induced by nalidixic acid in DE456Δphi456. This indicated that the released phage particles from DE456 were only phi456. We demonstrated that phi456 contributed to biofilm formation through spontaneous induction of the accompanying increase in the eDNA content. The survival ability of DE456Δphi456 was decreased in avian macrophage HD11 under oxidative stress and acidic conditions. This is likely due to a decrease in the transcription levels of three crucial genes-rpoS, katE, and oxyR-which are needed to help the bacteria adapt to and survive in adverse environments. It has been observed through animal experiments that the presence of phi456 in the DE456 genome enhances colonization ability in vivo. Additionally, the number of type I fimbriae in DE456Δphi456 was observed to be reduced under transmission electron microscopy when compared to the wild-type strain. The qRT-PCR results indicated that the expression levels of the subunit of I fimbriae (fimA) and its apical adhesin (fimH) were significantly lower in DE456Δphi456. Therefore, it can be concluded that phi456 plays a crucial role in helping bacterial hosts survive in unfavorable conditions and enhancing the colonization ability in DE456.


Assuntos
Bacteriófagos , Infecções por Escherichia coli , Animais , Escherichia coli/genética , Prófagos/genética , Galinhas/microbiologia , Adesinas Bacterianas/genética , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/veterinária
2.
Methods ; 213: 42-49, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37001685

RESUMO

A large amount of evidence shows that biomarkers are discriminant features related to disease development. Thus, the identification of disease biomarkers has become a basic problem in the analysis of complex diseases in the medical fields, such as disease stage judgment, disease diagnosis and treatment. Research based on networks have become one of the most popular methods. Several algorithms based on networks have been proposed to identify biomarkers, however the networks of genes or molecules ignored the similarities and associations among the samples. It is essential to further understand how to construct and optimize the networks to make the identified biomarkers more accurate. On this basis, more effective strategies can be developed to improve the performance of biomarkers identification. In this study, a multi-objective evolution algorithm based on sample similarity networks has been proposed for disease biomarker identification. Specifically, we design the sample similarity networks to extract the structural characteristic information among samples, which used to calculate the influence of the sample to each class. Besides, based on the networks and the group of biomarkers we choose in every iteration, we can divide samples into different classes by the importance for each class. Then, in the process of evolution algorithm population iteration, we develop the elite guidance strategy and fusion selection strategy to select the biomarkers which make the sample classification more accurate. The experiment results on the five gene expression datasets suggests that the algorithm we proposed is superior over some state-of-the-art disease biomarker identification methods.


Assuntos
Algoritmos , Biomarcadores
3.
Eur J Anaesthesiol ; 41(4): 305-313, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38298060

RESUMO

BACKGROUND: Tracheal injuries, vocal cord injuries, sore throat and hoarseness are common complications of double-lumen tube (DLT) intubation. OBJECTIVE: This study aimed to evaluate the effects of 'video double-lumen tubes' (VDLTs) on intubation complications in patients undergoing thoracic surgery. DESIGN: A randomised controlled study. SETTINGT: Xuzhou Cancer Hospital, Xuzhou, China, from January 2023 to June 2023. PATIENTS: One hundred eighty-two patients undergoing elective thoracic surgery with one-lung ventilation were randomised into two groups: 90 in the DLT group and 92 in the VDLT group. INTERVENTION: VDLT was selected for intubation in the VDLT group, and DLT was selected for intubation in the DLT group. A fibreoptic bronchoscope (FOB) was used to record tracheal and vocal cord injuries. MAIN OUTCOME MEASURES: The primary outcomes were the incidence of moderate-to-severe tracheal injury and the incidence of vocal cord injury. The secondary outcomes included the incidence and severity of postoperative 24 and 48 h sore throat and hoarseness. RESULTS: The incidence of moderate-to-severe tracheal injury was 32/90 (35.6%) in the DLT group, and 45/92 (48.9%) in the VDLT group ( P  = 0.077; relative risk 1.38, 95% CI, 0.97 to 1.95). The incidence of vocal cord injury was 31/90 (34.4%) and 34/92 (37%) in the DLT and VDLT groups, respectively ( P  = 0.449). The incidence of postoperative 24 h sore throat and hoarseness was significantly higher in the VDLT group than in the DLT group (for sore throat: P  = 0.032, relative risk 1.63, 95% CI, 1.03 to 2.57; for hoarseness: P  = 0.018, relative risk 1.48, 95% CI, 1.06 to 2.06). CONCLUSION: There was no statistically significant difference in the incidence of moderate-to-severe tracheal injury and vocal cord injury between DLTs and VDLTs. While improving the first-attempt success rate, intubation with VDLT increased the incidence of postoperative 24 h sore throat and hoarseness. TRIAL REGISTRATION: Chinese Clinical Trial Registry identifier: ChiCTR2300067348.


Assuntos
Faringite , Cirurgia Torácica , Procedimentos Cirúrgicos Torácicos , Humanos , Rouquidão/diagnóstico , Rouquidão/epidemiologia , Rouquidão/etiologia , Procedimentos Cirúrgicos Torácicos/efeitos adversos , Broncoscópios , Faringite/epidemiologia , Faringite/etiologia
4.
Foodborne Pathog Dis ; 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38484311

RESUMO

The foodborne pathogens have a serious threat to human health, especially Listeria monocytogenes. NADPH oxidase (NOX) is involved in cellular respiration and the production of reactive oxygen species (ROS), acting as messengers to host cells during the infection. However, the role of nox in the process of L. monocytogenes infection is unclear. In this study, we examined the impact of nox in L. monocytogenes by gene deletion. The results of cell experiment showed that knocking out nox from L. monocytogenes strain EGDe resulted in a twofold increase invasion ability to Caco-2 cells compared with that of wild-type strain (WT), but did not affect adhesion ability. Animal infection assays also showed that bacterial loads in the liver and spleen of mice challenged with EGDe-Δnox were approximately two times higher compared with those challenged with the WT strain. On the one hand, quantitative real-time polymerase chain reaction revealed that deletion of nox leads to upregulation of genes related to the internalization of L. monocytogenes (inlA, inlB, and inlC). More importantly, the expression of listeriolysin-positive regulatory (prfA) gene increased by three times in vivo compared with that of WT. On the other hand, the deletion of nox resulted in a reduction of the upregulation of proinflammatory factors in EGDe-Δnox compared with the WT and complementary strains. Thus, our study revealed that nox affected the virulence of L. monocytogenes by upregulating the expression of virulence genes and regulating the production of ROS and inflammatory factors in vivo.

5.
Angew Chem Int Ed Engl ; : e202406597, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38757727

RESUMO

Artificial interfaces provide a comprehensive approach to controlling zinc dendrite and surface corrosion in zinc-based aqueous batteries (ZABs). However, due to consistent volume changes during zinc plating/stripping, traditional interfacial layers cannot consistently adapt to the dendrite surface, resulting in uncontrolled dendrite growth and hydrogen evolution. Herein, dynamic covalent bonds exhibit the Janus effect towards zinc deposition at different current densities, presenting a holistic strategy for stabilizing zinc anode. The PBSC intelligent artificial interface consisting of dynamic B-O covalent bonds is developed on zinc anode to mitigate hydrogen evolution and restrict dendrite expansion. Owing to the reversible dynamic bonds, PBSC exhibits shape self-adaptive characteristics at low current rates, which rearranges the network to accommodate volume changes during zinc plating/stripping, resisting hydrogen evolution. Moreover, the rapid association of B-O dynamic bonds enhances mechanical strength at dendrite tips, presenting a shear-thickening effect and suppressing further dendrite growth at high current rates. Therefore, the assembled symmetrical battery with PBSC maintains a stable cycle of 4500 hours without significant performance degradation and the PBSC@Zn||V2O5 pouch cell demonstrates a specific capacity exceeding 170 mAh g-1. Overall, the intelligent interface with dynamic covalent bonds provides innovative approaches for zinc anode interfacial engineering and enhances cycling performance.

6.
Small ; 19(48): e2304290, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37525345

RESUMO

Developing stable silicon-based and lithium metal anodes still faces many challenges. Designing new highly practical silicon-based anodes with low-volume expansion and high electrical conductivity, and inhibiting lithium dendrite growth are avenues for developing silicon-based and lithium metal anodes, respectively. In this study, SiOx Cy microtubes are synthesized using a chemical vapor deposition method. As Li-ion battery anodes, the as-prepared SiOx Cy not only combines the advantages of nanomaterials and the practical properties of micromaterials, but also exhibits high initial Coulombic efficiency (80.3%), low volume fluctuations (20.4%), and high cyclability (98% capacity retention after 1000 cycles). Furthermore, SiOx Cy , as a lithium deposition substrate, can effectively promote the uniform deposition of metallic lithium. As a result, low nucleation overpotential (only 6.0 mV) and high Coulombic efficiency (≈98.9% after 650 cycles, 1.0 mA cm-2 and 1.0 mAh cm-2 ) are obtained on half cells, as well as small voltage hysteresis (only 9.5 mV, at 1.0 mA cm-2 ) on symmetric cells based on SiOx Cy . Full batteries based on both SiOx Cy and SiOx Cy @Li anodes demonstrate great practicality. This work provides a new perspective for the simultaneous development of practical SiOx Cy and dendrite-free lithium metal anodes.

7.
Microb Ecol ; 86(3): 1589-1603, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36717391

RESUMO

Terrestrial microbial consortia were reported to play fundamental roles in the global carbon cycle and renewable energy production through the breakdown of complex organic carbon. However, we have a poor understanding of how biotic/abiotic factors combine to influence consortia assembly and lignocellulose degradation in aquatic ecosystems. In this study, we used 96 in situ lignocellulose enriched, coastal intertidal zone-derived bacterial consortia as the initial inoculating consortia and developed 384 cultured consortia under different lignocellulose substrates (aspen, pine, rice straw, and purified Norway spruce lignin) with gradients of salinity and temperature. As coastal consortia, salinity was the strongest driver for assembly, followed by Norway spruce lignin, temperature, and aspen. Moreover, a conceptual model was proposed to demonstrate different succession dynamics between consortia under herbaceous and woody lignocelluloses. The succession of consortium under Norway spruce lignin is greatly related with abiotic factors, while its substrate degradation is mostly correlated with biotic factors. A discrepant pattern was observed in the consortium under rice straw. Finally, we developed four groups of versatile, yet specific consortia. Our study not only reveals that coastal intertidal wetlands are important natural resources to enrich lignocellulolytic degrading consortia but also provides insights into the succession and ecological function of coastal consortium.


Assuntos
Lignina , Oryza , Lignina/metabolismo , Ecossistema , Bactérias/metabolismo , Consórcios Microbianos , Oryza/metabolismo
8.
Angew Chem Int Ed Engl ; 62(29): e202304454, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37218359

RESUMO

Metallic Zinc (Zn) is considered as a remarkably promising anode for aqueous Zn-ion batteries due to its high volumetric capacity and low redox potential. Unfortunately, dendritic growth and severe side reactions destabilizes the electrode/electrolyte interface, and ultimately reduce the electrochemical performance. Here, an artificial protective layer (APL) with a regulated ion and electron-conducting interphase is constructed on the Zn-metal anode to provide excellent interfacial stability in high-rate cycling. The superior ionic and moderate electronic conductivity of the APL derives from the co-embedding of MXene and Zn(CF3 SO3 )2 salts into the polyvinyl alcohol hydrogel, which enables a synergistic effect of local current density reduction during plating and ion transport acceleration during stripping for Zn anode. Furthermore, the high Young's modulus of the protective layer and dendrite-free deposition morphology during cycling suppresses hydrogen evolution reactions (2.5 mmol h-1 cm-2 ) and passivation. As a result, in symmetrical cell tests, the modified battery presents a stable life of over 2000 cycles at ultra-high current density of 20 mA cm-2 . This research presents a new insight into the formation and regulation of stable electrode-electrolyte interface for the Zn-metal anode.

9.
Artigo em Inglês | MEDLINE | ID: mdl-35696264

RESUMO

A novel bacterium, designated NAS39T, was isolated from the interfacial sediment of Taihu Lake in PR China and its taxonomic position was investigated by using a polyphasic approach. Cells of the isolate were Gram-stain-negative, aerobic, non-motile, catalase-positive, yellow and rod-shaped. Phylogenetic analyses based on 16S rRNA gene sequences supported that strain NAS39T formed a cluster within the genus Flavobacterium, and was most closely related to Flavobacterium laiguense LB2P30T (98.4 %), followed by Flavobacterium tiangeerense 0563T (97.4 %). The average nucleotide identity values between strain NAS39T and F. laiguense LB2P30T and F. tiangeerense 0563T were 82.5 and 75.3 %, respectively. The digital DNA-DNA hybridization values between strain NAS39T and F. laiguense LB2P30T and F. tiangeerense 0563T were 40.9 and 18.6 %, respectively. The genomic DNA G+C content was 34.1 mol%. The major respiratory quinone was menaquinone-6. The dominant cellular fatty acids were iso-C15 : 0 and summed feature 3 comprising C16 : 1 ω7c/C16 : 1 ω6c. The polar lipids comprised phosphatidyl ethanolamine, two amino lipids, three amino phospholipids and two unidentified lipids. Based on the phenotypic, chemotaxonomic, genotypic and phylogenetic characteristics, strain NAS39T (=MCCC 1K06094T=KACC 22328T) represents a novel species of the genus Flavobacterium, for which the name Flavobacterium taihuense sp. nov. is proposed.


Assuntos
Flavobacterium , Lagos , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Lagos/análise , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análise
10.
Sensors (Basel) ; 21(21)2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34770459

RESUMO

Loran-C is the most essential backup and supplementary system for the global navigation satellite system (GNSS). Continuous wave interference (CWI) is one of the main interferences in the Loran-C system, which will cause errors in the measurement of the time of arrival, thereby affecting positioning performance. The traditional adaptive notch filter method needs to know the frequency of CWI when removing it, and the number is limited. This paper presents a method based on sparseness to suppress the CWI in the Loran-C signal. According to the different morphological characteristics of the Loran-C signal and the CWI, we construct dictionaries suitable for the two components, respectively. We use the tunable Q-factor wavelet transform and the discrete cosine transform to make the two components obtain a good sparse representation in their respective dictionaries. Then, the two components are separated using the morphological component analysis theory. We illustrate this method using both synthetic data and actual data. A huge advantage of the proposed method is that there is no need to know the frequencies of the CWI for it can better cope with frequency changes of the CWI in the actual environments. Compared with the adaptive notch filter method, the results of the proposed method show that our approach is more effective and convenient.

11.
BMC Plant Biol ; 20(1): 189, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32357837

RESUMO

BACKGROUND: Colletotrichum species are the causal agents of anthracnose, a major disease affecting the yield and quality of pepper (Capsicum spp.). Colletotrichum scovillei is widespread in China, has strong pathogenicity and drug resistance, and causes anthracnose disease in pepper fruits that severely reduces production. Previously, an anti-anthracnose locus AnRGO5 was mapped to the P5 chromosome on the basis of analyses of fruit at the green mature stage. The aim of this study was to narrow down the interval of this locus and identify the gene responsible for conferring resistance. RESULTS: On the basis of results of re-sequencing of Capsicum chinense 'PBC932' and C. annuum '77013', we developed Kompetitive allele-specific PCR (KASPar) markers and insertion-deletion (InDel) markers linked to AnRGO5 at the green mature fruit stage and used them to construct a genetic linkage map (42 markers, 24.4 cM in length). Using data obtained in phenotypic and genotypic analyses of BC4S1, BC4S2, and BC4S3 populations, AnRGO5 was located between the markers P5in-2266-404 and P5in-2268-978 within a physical distance of 164 kb. This region contained five genes, including CA05g17730. CA05g17730 encodes 'R1C-3-like' putative late blight resistance protein homologs. The transcript level of CA05g17730 differed between 'PBC932' and '77013'. The structure of the CA05g17730 gene also differed between 'PBC932' and '77013'. CONCLUSIONS: We narrowed down the QTL interval to a region containing five genes. These results will be useful for further research on the mechanisms of resistance to anthracnose, and for marker assisted selection for anthracnose-resistant capsicum lines.


Assuntos
Capsicum/microbiologia , Mapeamento Cromossômico , Cromossomos de Plantas , Colletotrichum , Genes de Plantas , Doenças das Plantas/genética , Capsicum/genética , Resistência à Doença/genética , Fenótipo , Doenças das Plantas/microbiologia , Locos de Características Quantitativas , Transcriptoma
12.
Opt Lett ; 45(14): 3889-3892, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32667311

RESUMO

An ultracompact twisted silica taper with an asymmetric structure is fabricated by fire-drawing two twisted single-mode fibers for broadband ultrasound sensing. A piezoelectric transducer (PZT), peaked at 3.7 MHz, is used as an ultrasound generator. A steel plate with a silica taper attached is adhered to the PZT and is used as the ultrasound propagation medium. The transmission spectrum of the silica taper has high contrast owing to multimode interference in this twisted silica structure. Specially, the taper waist length and waist diameter are optimized for the highest optical sensitivity with high contrast at high slope in the transmission spectrum. The ultrasound sensitivity is characterized by a different thickness of the steel plate from 0 to 2.36 mm to achieve the highest ultrasound frequency response. With the taper waist length of 5 mm, waist diameter of 5 µm, and steel thickness of 0 mm, a broadband ultrasound frequency of 20 kHz to 94.4 MHz can be detected at high harmonics of the PZT, verifying the high sensitivity of the compact twisted silica taper.

13.
Int J Syst Evol Microbiol ; 70(11): 5950-5957, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33048042

RESUMO

A taxonomic identification using a polyphasic approach was performed on strain NBS58-1T, which was isolated from the interfacial sediment of Taihu Lake in China. Strain NBS58-1T was Gram-stain-negative, aerobic, non-spore-forming and catalase-positive. Phylogenetic analyses based on 16S rRNA gene and three housekeeping genes (rpoB, gyrB and dnaK) sequences supported the position that strain NBS58-1T should be classified within the genus Rufibacter. The 16S rRNA gene sequence of strain NBS58-1T possessed the highest similarity to Rufibacter sediminis H-1T (96.60 %), followed by Rufibacter glacialis MDT1-10-3T (96.17 %). And the ANI value between strain NBS58-1T and R. glacialis MDT1-10-3T was 79.3 %. The respiratory quinone was menaquinone 7 (MK-7). The major cellular fatty acids comprised iso-C15 : 0 and summed feature 3. Phosphatidylethanolamine, two unidentified phospholipids and four unidentified lipids were the main polar lipids. The genomic DNA G+C content was 51.3 mol%. Based on phenotypic features and phylogenetic position, a novel species with the name Rufibacter hautae sp. nov. is proposed. The type strain is NBS58-1T=(KACC 21309T=MCCC 1K04037T). We also proposed Rufibacter quisquiliarum as a latter heterotypic synonym of Rufibacter ruber.


Assuntos
Bacteroidetes/classificação , Sedimentos Geológicos/microbiologia , Lagos/microbiologia , Filogenia , Técnicas de Tipagem Bacteriana , Bacteroidetes/isolamento & purificação , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
14.
Int J Syst Evol Microbiol ; 70(3): 1987-1992, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31999238

RESUMO

An aerobic, Gram-stain-negative, non-spore-forming and rod-shaped bacterial strain, designated N8T, was isolated from the interfacial sediment of Taihu Lake in PR China. The strain formed white to blue colonies on R2A agar. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain N8T represented a member of the genus Gemmobacter and was most closely related to Gemmobacter aquaticus A1-9T (97.97 %). The average nucleotide identity and digital DNA-DNAhybridization values between strain N8T and G. aquaticus A1-9T based on their whole genomes were 78.8 and 21.7 %, respectively. Q-10 was the main predominant ubiquinone. The major fatty acids were summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c), C18 : 0 and C16 : 0. The G+C content of the genomic DNA was 66.1 mol%. The polar lipids comprised phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, one unidentified phospholipid, two unidentified glycolipids and two unidentified lipids. Based on its physiological, biochemical and chemotaxonomic characteristics, strain N8T represents a novel species of the genus Gemmobacter, for which the name Gemmobacter caeruleus sp. nov. is proposed. The type strain is N8T=(KACC 21307T=MCCC 1K04036T).


Assuntos
Sedimentos Geológicos/microbiologia , Lagos/microbiologia , Filogenia , Rhodobacteraceae/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Rhodobacteraceae/isolamento & purificação , Análise de Sequência de DNA , Ubiquinona/análogos & derivados , Ubiquinona/química
15.
Int J Syst Evol Microbiol ; 69(4): 1231-1236, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30785393

RESUMO

An aerobic, motile, Gram-stain-negative bacterium, designated strain NS1T, was isolated from interfacial sediment from Taihu Lake, China. The strain formed yellow colonies on R2A medium. Cells were ovoid to rod-shaped and non-spore-forming. Growth occurred at 15-40 °C (optimum, 28 °C), at pH 5.0-10.5 (optimum, 6.5-7.5) and in the presence of 0-1 % (w/v) NaCl (optimum, 0 %). Phylogenetic trees based on 16S rRNA gene sequences showed that strain NS1T represented a member of the genus Altererythrobacter and had the highest sequence similarity to Altererythrobacter troitsensis CCTCC AB 2015180T (97.1 %). The average nucleotide identity value between strain NS1T and the closest related strain based on their genomes was 78.6 %. The predominant ubiquinone was Q-10. The major fatty acids were summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c), summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) and C16 : 0. The polar lipids comprised diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, an unidentified phospholipid, an unidentified glycolipid and six unidentified lipids. The genomic DNA G+C content was 66.6 mol%. On the basis of phenotypic and genotypic characteristics, strain NS1T represents a novel species of the genus Altererythrobacter, for which the name Altererythrobacter amylolyticus sp. nov. is proposed. The type strain is NS1T (=CGMCC 1.13679T=NBRC 113553T).


Assuntos
Alphaproteobacteria/classificação , Sedimentos Geológicos/microbiologia , Lagos/microbiologia , Filogenia , Alphaproteobacteria/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/análogos & derivados , Ubiquinona/química
16.
Opt Express ; 26(8): 11025-11033, 2018 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-29716030

RESUMO

A fringe visibility enhanced fiber-optic Fabry-Perot interferometer based ultrasonic sensor is proposed and experimentally demonstrated for seismic physical model imaging. The sensor consists of a graded index multimode fiber collimator and a PTFE (polytetrafluoroethylene) diaphragm to form a Fabry-Perot interferometer. Owing to the increase of the sensor's spectral sideband slope and the smaller Young's modulus of the PTFE diaphragm, a high response to both continuous and pulsed ultrasound with a high SNR of 42.92 dB in 300 kHz is achieved when the spectral sideband filter technique is used to interrogate the sensor. The ultrasonic reconstructed images can clearly differentiate the shape of models with a high resolution.

17.
Reproduction ; 154(4): 433-444, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28687593

RESUMO

Controlled ovarian hyperstimulation (COH) is widely used for the treatment of infertility, while the long-term effects of COH on the reproductive function in female offspring are currently unknown. Based on the fact that COH could cause high E2 levels in women throughout pregnancy and excess estrogenic exposure during fetal development is harmful to subsequent adult ovarian function, we assumed the hypothesis that COH disrupts reproductive function in female offspring. To test this hypothesis, COH was induced in mice to obtain female offspring by pregnant mare serum gonadotropin (PMSG) and HCG, and then we evaluated pubertal transition, serum levels of E2, anti-Mullerian hormone (AMH), FSH and LH, mRNA expressions of Esr1, Amhr2, Fshr and Lhcgr in ovaries, number of follicles and ovarian histology. We also investigated the apoptosis of follicles by TUNEL; the mRNA expressions of Fas, FasL, Bax, Bcl2, and caspase 3, 8 and 9 by quantitative real-time PCR; and the protein expressions of cleaved-caspase (CASP) 3, 8 and 9 by Western blot. Moreover, we further observed estrous cyclicity in young adult offspring, performed follicle counting and measured the level of AMH in both serum and ovary. COH could induce detrimental pregnancy outcomes, as well as delayed pubertal transition and irregular estrous cycle due to the aberrant growth and maturation of follicles in female offspring. Our novel findings add new evidence to better understand the potential risks of COH on the reproductive function in female offspring, raising the awareness that COH could exert adverse effects on female offspring, rather than just obtain more oocytes for fertilization.


Assuntos
Ciclo Estral/efeitos dos fármacos , Fármacos para a Fertilidade Feminina/toxicidade , Ovário/efeitos dos fármacos , Indução da Ovulação/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal , Desenvolvimento Sexual/efeitos dos fármacos , Fatores Etários , Animais , Hormônio Antimülleriano/sangue , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Estradiol/sangue , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Ciclo Estral/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Regulação da Expressão Gênica no Desenvolvimento , Hormônio Luteinizante/sangue , Camundongos , Ovário/metabolismo , Ovário/patologia , Gravidez , Receptores do FSH/genética , Receptores do FSH/metabolismo , Receptores do LH/genética , Receptores do LH/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/genética , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Medição de Risco , Transdução de Sinais/efeitos dos fármacos
18.
Med Sci Monit ; 22: 2656-63, 2016 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-27460133

RESUMO

BACKGROUND Vasa (a DEAD-box helicase, also known as Ddx4) is an ATP-dependent RNA helicase highly conserved among all animals. Research on the presence and function of DDX4 in female mammals is limited. To gain greater insight into its distribution and role in female mice, we detected the expression of DDX4 protein in the ovaries and analyzed its expression pattern. MATERIAL AND METHODS MVH was detected in the cytoplasm of oocytes in all non-apoptotic follicles. RESULTS In the present study, we found that higher expression levels of ~55-60 kDa MVH isoform in the ovaries were followed by the accumulations of preovulatory follicles. CONCLUSIONS Higher levels of MVH protein in the ovaries might prepare oocytes for the competence to resume meiosis.


Assuntos
RNA Helicases DEAD-box/biossíntese , Ovário/enzimologia , Animais , RNA Helicases DEAD-box/genética , Feminino , Perfilação da Expressão Gênica , Camundongos , Camundongos Endogâmicos C57BL , Oócitos/metabolismo , RNA Mensageiro/metabolismo
19.
Saudi Pharm J ; 24(3): 354-62, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27275127

RESUMO

This study is to establish a model of rat tibial osteocarcinoma pain, intrathecally inject specific ERK1/2 inhibitors SCH772984, observe the analgesic effect, and discuss the influence of ERK-P90RSK-Fos signal path in bone cancer pain. Forty female SD rats were randomly divided into 5 groups. Establish a bone cancer pain model after putting the intrathecal tube 5d and determine the rats' mechanical withdrawal threshold (MWT) after tube 5d; 40 SD rats with intrathecal tube back 5d were randomly divided into 5 groups. Sham Group receives no medication, the other four respectively receive 5% DMSO 10 µl, SCH 0.1, 1.0, 10 µg (SCH dissolved in 10 µl 5% DMSO) intrathecally. Determine the rats' mechanical withdrawal threshold (MWT) before and after giving medication 1, 3, 6, 9, 12, 15, 18, 24 h, and 2 min spontaneous paw withdrawal. Western blot and immuno-fluorescence determine the expression condition of spinal cord dorsal horn of p-ERK, p-p90RSK and Fos protein. Intrathecal injection of SCH772984 has analgesic effects on rats with bone cancer pain, and the effects enhance with increasing dose; intrathecal injection of SCH772984 10 µg could greatly reduce the expression of spinal dorsal horn Fos protein. Injecting walker 256 tumor cells into rats' tibia could cause behavior changes, such as idiopathic pain sensitivity and pain; the intrathecal tube almost has no effect on motor function of rats; ERK1/2 is involved in bone cancer pain, and intrathecal injection of ERK1/2 specific inhibitors SCH772984 10 µg may effectively relieve bone cancer pain.

20.
Biotechnol Lett ; 37(3): 609-17, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25376333

RESUMO

Corynebacterium glutamicum is well-established for industrial and biotechnological applications. However, its genetic manipulation has generally lagged behind traditional genetic models. In this study, a counter-selectable marker gene upp was firstly confirmed to be more efficient than traditional sacB. Furthermore, a markerless gene replacement system was developed by combining upp with double-strand break repair caused by the exogenous endonuclease I-SceI. Finally, genetic modification using a dsDNA PCR fragment was carried out with the expression of recombinase/exonuclease RecE/RecT. Our results show that the genetic modification system allows precise and markerless gene replacement without altering the chromosome, with a simplified screening procedure to generate its modification.


Assuntos
Corynebacterium glutamicum/genética , Genética Microbiana/métodos , Biologia Molecular/métodos , Recombinação Genética , Seleção Genética , Corynebacterium glutamicum/enzimologia , Enzimas de Restrição do DNA/genética , Enzimas de Restrição do DNA/metabolismo , Exodesoxirribonucleases/genética , Exodesoxirribonucleases/metabolismo , Recombinases/genética , Recombinases/metabolismo
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