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1.
Artigo em Inglês | MEDLINE | ID: mdl-38864839

RESUMO

A Gram-stain-positive, strictly anaerobic, endospore-forming and rod-shaped (0.6-0.8×2.7-13.1 µm) bacterium, designated as 5 N-1T, was isolated from a yellow water sample collected from the manufacturing process of Nongxiangxing baijiu in the Yibin region of Sichuan, PR China. Growth occurred at 15-40 °C (optimum growth at 37 °C), at pH 6.0-9.0 (optimum growth at pH 7.0) and in NaCl concentrations of 0-1 % (w/v) and ethanol concentrations of 0-2 % (v/v). The major fatty acids in strain 5 N-1T were C16 : 0, C18 : 0 and C14 : 0. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, four unidentified aminophospholipids and one unidentified lipid. Phylogenetic analysis of its 16S rRNA gene sequence indicated that strain 5 N-1T was most closely related to Clostridium weizhouense YB-6T (97.70 %) and Clostridium uliginosum DSM 12992T (97.56 %). The average nucleotide identity and digital DNA‒DNA hybridization values between strain 5 N-1T and the above two type strains were 80.89 and 80.05 % and 25.80 and 25.30 %, respectively, which were all below the species thresholds. The genome size of strain 5 N-1T was 3.5 Mbp and the DNA G+C content was 27.5 mol%. Based on the results of phenotypic and genotypic analyses, strain 5 N-1T represents a novel species of the genus Clostridium, for which the name Clostridium aquiflavi sp. nov. is proposed. The type strain is Clostridium aquiflavi 5 N-1T (=CICC 24886T=JCM 35355T).


Assuntos
Técnicas de Tipagem Bacteriana , Composição de Bases , Clostridium , DNA Bacteriano , Ácidos Graxos , Hibridização de Ácido Nucleico , Filogenia , RNA Ribossômico 16S , Análise de Sequência de DNA , China , RNA Ribossômico 16S/genética , Ácidos Graxos/análise , DNA Bacteriano/genética , Clostridium/genética , Clostridium/isolamento & purificação , Clostridium/classificação , Microbiologia da Água , Fosfolipídeos/análise
2.
Arterioscler Thromb Vasc Biol ; 43(4): 562-580, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36756879

RESUMO

BACKGROUND: Postprandial dyslipidemia is a causative risk factor for cardiovascular disease. The majority of absorbed dietary lipids are packaged into chylomicron and then delivered to circulation. Previous studies showed that Surf4 (surfeit locus protein 4) mediates very low-density lipoprotein secretion from hepatocytes. Silencing hepatic Surf4 markedly reduces the development of atherosclerosis in different mouse models of atherosclerosis without causing hepatic steatosis. However, the role of Surf4 in chylomicron secretion is unknown. METHODS: We developed inducible intestinal-specific Surf4 knockdown mice (Surf4IKO) using Vil1Cre-ERT2 and Surf4flox mice. Metabolic cages were used to monitor mouse metabolism. Enzymatic kits were employed to measure serum and tissue lipid levels. The expression of target genes was detected by qRT-PCR and Western Blot. Transmission electron microscopy and radiolabeled oleic acid were used to assess the structure of enterocytes and intestinal lipid absorption and secretion, respectively. Proteomics was performed to determine changes in protein expression in serum and jejunum. RESULTS: Surf4IKO mice, especially male Surf4IKO mice, displayed significant body weight loss, increased mortality, and reduced metabolism. Surf4IKO mice exhibited lipid accumulation in enterocytes and impaired fat absorption and secretion. Lipid droplets and small lipid vacuoles were accumulated in the cytosol and the endoplasmic reticulum lumen of the enterocytes of Surf4IKO mice, respectively. Surf4 colocalized with apoB and co-immunoprecipitated with apoB48 in differentiated Caco-2 cells. Intestinal Surf4 deficiency also significantly reduced serum triglyceride, cholesterol, and free fatty acid levels in mice. Proteomics data revealed that diverse pathways were altered in Surf4IKO mice. In addition, Surf4IKO mice had mild liver damage, decreased liver size and weight, and reduced hepatic triglyceride levels. CONCLUSIONS: Our findings demonstrate that intestinal Surf4 plays an essential role in lipid absorption and chylomicron secretion and suggest that the therapeutic use of Surf4 inhibition requires highly cell/tissue-specific targeting.


Assuntos
Aterosclerose , Mucosa Intestinal , Humanos , Masculino , Animais , Camundongos , Mucosa Intestinal/metabolismo , Células CACO-2 , Absorção Intestinal/fisiologia , Gorduras na Dieta , Quilomícrons/metabolismo , Metabolismo dos Lipídeos/genética , Triglicerídeos/metabolismo , Aterosclerose/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo
3.
Antonie Van Leeuwenhoek ; 116(2): 143-151, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36309905

RESUMO

A Gram-negative, non-motile rod and strictly aerobic bacterium, designated as 18B16333T, was isolated from vertebral puncture tissue of a patient at Peking union medical college hospital in China. Growth occurred in NaCl concentrations of 0-1% (w/v) (optimum growth at 0% NaCl), at temperatures of 25-40 °C (optimum growth at 37 °C) and at pH 6.0-9.0 (optimum growth at pH 8.0). Diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine were the predominant polar lipids, and the major fatty acids were C16:0, C18:1 ω7c/C18:1 ω6c and C16:1 ω7c/C16:1 ω6c. Phylogenetic analysis based on 16S rRNA gene sequence comparisons indicated that strain 18B16333T was most closely related to Kingella potus CCUG 49773 T (97.3%, 16S rRNA gene sequence identity) and Neisseria bacilliformis CCUG 50858 T (96.8%). The ANI values between strain 18B16333T and the type strains K. potus CCUG 49773 T, N. bacilliformis CCUG 50858 T, Kingella kingae CCUG 352 T and Neisseria gonorrhoeae CCUG 26876 T were 77.3%, 79.1%, 72.1% and 75.4%, respectively. The dDDH values between strain 18B16333T and the four reference strains mentioned above were 24.8%, 26.9%, 24.2% and 20.7%. Further core gene analysis distinctively clustered strain 18B16333T with four Kingella species but not with Neisseria species. Based on the phenotypic, chemotaxonomic, and phylogenetic properties, strain 18B16333T represents a novel species of the genus Kingella, for which the name Kingella pumchi sp. nov. is proposed. The type strain is Kingella pumchi 18B16333T (= CICC 24913 T = CCUG 75125 T).


Assuntos
Kingella , Filogenia , Punção Espinal , Humanos , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Ácidos Graxos/química , Kingella/classificação , Kingella/isolamento & purificação , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/química
4.
Int J Mol Sci ; 24(21)2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37958555

RESUMO

MYCN amplification occurs in approximately 20-30% of neuroblastoma patients and correlates with poor prognosis. The TH-MYCN transgenic mouse model mimics the development of human high-risk neuroblastoma and provides strong evidence for the oncogenic function of MYCN. In this study, we identified mitotic dysregulation as a hallmark of tumor initiation in the pre-cancerous ganglia from TH-MYCN mice that persists through tumor progression. Single-cell quantitative-PCR of coeliac ganglia from 10-day-old TH-MYCN mice revealed overexpression of mitotic genes in a subpopulation of premalignant neuroblasts at a level similar to single cells derived from established tumors. Prophylactic treatment using antimitotic agents barasertib and vincristine significantly delayed the onset of tumor formation, reduced pre-malignant neuroblast hyperplasia, and prolonged survival in TH-MYCN mice. Analysis of human neuroblastoma tumor cohorts showed a strong correlation between dysregulated mitosis and features of MYCN amplification, such as MYC(N) transcriptional activity, poor overall survival, and other clinical predictors of aggressive disease. To explore the therapeutic potential of targeting mitotic dysregulation, we showed that genetic and chemical inhibition of mitosis led to selective cell death in neuroblastoma cell lines with MYCN over-expression. Moreover, combination therapy with antimitotic compounds and BCL2 inhibitors exploited mitotic stress induced by antimitotics and was synergistically toxic to neuroblastoma cell lines. These results collectively suggest that mitotic dysregulation is a key component of tumorigenesis in early neuroblasts, which can be inhibited by the combination of antimitotic compounds and pro-apoptotic compounds in MYCN-driven neuroblastoma.


Assuntos
Antimitóticos , Neuroblastoma , Humanos , Camundongos , Animais , Proteína Proto-Oncogênica N-Myc/genética , Proteína Proto-Oncogênica N-Myc/metabolismo , Linhagem Celular Tumoral , Camundongos Transgênicos , Neuroblastoma/tratamento farmacológico , Neuroblastoma/genética , Neuroblastoma/patologia , Transformação Celular Neoplásica/genética , Regulação Neoplásica da Expressão Gênica
5.
Curr Microbiol ; 79(7): 193, 2022 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-35579721

RESUMO

Based on entire genome sequencing, this study focused on the classification of Aspergillus niger aggregation species and investigated their potential for fumonisin B2 (FB2) and ochratoxin A (OTA) production. In the current study, 22 strains were used, namely 17 A. niger strains, four A. welwitschiae strains, and one A. lacticoffeatus (a synonym of A. niger) strain. Traditional multigene phylogenetic analysis, average nucleotide identity analysis (ANI), and the whole-genome single-nucleotide polymorphism (SNP) analyses were used to reconfirm the taxonomic status of A. niger, A. welwitschiae, and A. lacticoffeatus. The ability of A. niger to produce FB2 and OTA on five culture substrates was determined, and the association between FB2 and OTA gene clusters and toxin-producing abilities was explored. The results revealed that the ANI method could distinguish A. niger from A. welwitschiae, with an ANI value of < 98%. The SNP-based phylogenetic analysis suggested that A. niger and A. welwitschiae were two independent phylogenetic species. The ANI, SNP, and multigene phylogenetic analysis supported previous findings that A. lacticoffeatus was a synonymous species of A. niger. Aspergillus niger strains exhibited the varied potential of producing FB2 and OTA on different culture media. The A. niger genome sequence analysis revealed no significant difference in fumonisin gene clusters between FB2-nonproducing isolates and FB2-producing isolates, and the integrity of the ochratoxin biosynthesis genes cluster was clearly associated with OTA production. In conclusion, gene sequencing can be useful in assessing A. niger's ability to produce OTA, but it cannot reliably predict its ability to produce FB2.


Assuntos
Fumonisinas , Ocratoxinas , Aspergillus , Aspergillus niger , Filogenia , Polimorfismo de Nucleotídeo Único
6.
Nanomedicine ; 41: 102530, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35104672

RESUMO

This project aimed to develop, optimize, and test an ultrasound-responsive targeted nanodroplet system for the delivery of osteoporosis-related silencing gene Cathepsin K small interfering RNA (CTSK siRNA) for osteoporosis treatment. The nanodroplet (ND) is composed of a gas core made from perfluorocarbon, stabilized with albumin, encapsulated with CTSK siRNA, and embedded with alendronate (AL) for bone targeting (CTSK siRNA-ND-AL). Following the development, the responsiveness of CTSK siRNA-ND-AL to a therapeutic ultrasound probe was examined. The results of biocompatibility tests with human bone marrow-derived mesenchymal stem cells proved no significant cell death (P > 0.05). When the CTSK siRNA-ND-AL was supplemented with human osteoclast precursors, they suppressed osteoclastogenesis. Thus, this project establishes the potential of nanotechnology and ultrasound to deliver genes into the osteoclasts. This research also presents a novel ultrasound responsive and targeted nanodroplet platform that can be used as a gene and drug delivery system for various diseases including cancer.


Assuntos
Osteoclastos , Osteoporose , Técnicas de Transferência de Genes , Humanos , Osteogênese/genética , Osteoporose/tratamento farmacológico , Osteoporose/genética , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo
7.
J Lipid Res ; 62: 100091, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34118252

RESUMO

Plasma LDL is produced from catabolism of VLDL and cleared from circulation mainly via the hepatic LDL receptor (LDLR). Proprotein convertase subtilisin/kexin type 9 (PCSK9) promotes LDLR degradation, increasing plasma LDL-C levels. Circulating PCSK9 is mainly secreted by the liver, whereas VLDL is exclusively secreted by hepatocytes. However, the mechanism regulating their secretion is not completely understood. Surfeit 4 (Surf4) is a cargo receptor localized in the ER membrane. It recruits cargos into coat protein complex II vesicles to facilitate their secretion. Here, we investigated the role of Surf4 in VLDL and PCSK9 secretion. We generated Surf4 liver-specific knockout mice and found that knockout of Surf4 did not affect PCSK9 secretion, whereas it significantly reduced plasma levels of cholesterol, triglyceride, and lipid-binding protein apolipoprotein B (apoB). In cultured human hepatocytes, Surf4 coimmunoprecipitated and colocalized with apolipoprotein B100, and Surf4 silencing reduced secretion of apolipoprotein B100. Furthermore, knockdown of Surf4 in LDLR knockout (Ldlr-/-) mice significantly reduced triglyceride secretion, plasma levels of apoB and non-HDL-C, and the development of atherosclerosis. However, Surf4 liver-specific knockout mice and Surf4 knockdown in Ldlr-/- mice displayed similar levels of liver lipids and plasma alanine aminotransferase activity as control mice, indicating that inhibition of Surf4 does not cause notable liver damage. Expression of stearoyl-CoA desaturase-1 was also reduced in the liver of these mice, suggesting a reduction in de novo lipogenesis. In summary, hepatic deficiency of Surf4 reduced VLDL secretion and the development of atherosclerosis but did not cause significant hepatic lipid accumulation or liver damage.


Assuntos
Aterosclerose/metabolismo , Lipoproteínas VLDL/metabolismo , Proteínas de Membrana/metabolismo , Animais , Células Cultivadas , Proteínas de Membrana/deficiência , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pró-Proteína Convertase 9/deficiência , Pró-Proteína Convertase 9/metabolismo , Receptores de LDL/deficiência , Receptores de LDL/metabolismo
8.
Extremophiles ; 25(1): 39-49, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33123748

RESUMO

Halomonas alkalicola CICC 11012s can grow at pH 12.5, the highest pH at which the organisms in the genus Halomonas can grow. Genomic analysis reveals that H. alkalicola adapts to alkaline stress using a variety of adaptive strategies; however, the detailed mechanism for its growth at high-alkaline conditions has not been elucidated. Therefore, in this study, the adaptations of H. alkalicola in response to extreme alkaline stress were investigated. A sharp decrease of alkaliphilic tolerance was observed in mutants E. coli ΔEctonB and H. alkalicola ΔHatonB. Expressions of the gene clusters encoding TonB-dependent transport system and iron complex transport system in H. alkalicola grown under extreme alkaline conditions were markedly up-regulated. We then compared the intracellular ionic iron content and iron-chelating ability of mutant strain with those of wild-type strain to understand the influence of TonB-dependent transport system on the alkaline responses. The results indicated that the presence of TonB-dependent transport system increased the alkaline tolerance of H. alkalicola grown at high-alkaline conditions, but had no effects when the strain was grown at neutral pH and low-alkaline conditions. Meanwhile, the presence of this system increased the transport and accumulation of ionic irons to maintain intracellular metabolic homeostasis, which in turn could increase the tolerance of the strain to extreme alkaline conditions. Based on the results, we established a model representing the interactions between TonB-dependent transport system, alkaline tolerance, and intracellular ionic iron that could help deepen the understanding of the alkaline response mechanism of alkaliphilic bacteria.


Assuntos
Proteínas de Bactérias/genética , Halomonas/metabolismo , Ferro/metabolismo , Proteínas de Membrana/genética , Estresse Fisiológico , Álcalis , Proteínas de Bactérias/metabolismo , Transporte Biológico , Escherichia coli/metabolismo , Halomonas/genética , Concentração de Íons de Hidrogênio , Proteínas de Membrana/metabolismo
9.
Br J Cancer ; 123(7): 1101-1113, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32684628

RESUMO

BACKGROUND: Epithelioid inflammatory myofibroblastic sarcoma (eIMS) is characterised by perinuclear ALK localisation, CD30 expression and early relapse despite crizotinib treatment. We aimed to identify therapies to prevent and/or treat ALK inhibitor resistance. METHODS: Malignant ascites, from an eIMS patient at diagnosis and following multiple relapses, were used to generate matched diagnosis and relapse xenografts. RESULTS: Xenografts were validated by confirmation of RANBP2-ALK rearrangement, perinuclear ALK localisation and CD30 expression. Although brentuximab-vedotin (BV) demonstrated single-agent activity, tumours regrew during BV therapy. BV resistance was associated with reduced CD30 expression and induction of ABCB1. BV resistance was reversed in vitro by tariquidar, but combination BV and tariquidar treatment only briefly slowed xenograft growth compared with BV alone. Combining BV with either crizotinib or ceritinib resulted in marked tumour shrinkage in both xenograft models, and resulted in prolonged tumour-free survival in the diagnosis compared with the relapse xenograft. CONCLUSIONS: CD30 is a therapeutic target in eIMS. BV efficacy is limited by the rapid emergence of resistance. Prolonged survival with combination ALK and CD30-targeted-therapy in the diagnosis model provides the rationale to trial this combination in eIMS patients at diagnosis. This combination could also be considered for other CD30-positive, ALK-rearranged malignancies.


Assuntos
Quinase do Linfoma Anaplásico/antagonistas & inibidores , Quinase do Linfoma Anaplásico/genética , Rearranjo Gênico , Antígeno Ki-1/antagonistas & inibidores , Chaperonas Moleculares/genética , Miofibroblastos/patologia , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Sarcoma/tratamento farmacológico , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Idoso de 80 Anos ou mais , Animais , Brentuximab Vedotin/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Humanos , Inflamação , Masculino , Camundongos , Sarcoma/genética , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Int J Syst Evol Microbiol ; 70(4): 2859-2866, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32195651

RESUMO

A Gram-stain-negative, catalase- and oxidase-positive, aerobic, rod-shaped, motile strain (PYC7WT) was isolated from Lake Pengyanco on the Tibetan Plateau. Comparisons based on 16S rRNA gene sequences showed that strain PYC7WT belongs to the genus Halomonas, with Halomonas malpeensis YU-PRIM-29T and Halomonas johnsoniae T68687T as its closest neighbours (96.8 and 96.6 % 16S rRNA gene sequence similarity, respectively), and only 93.1 % 16S rRNA gene sequence similarity to Halomonas elongata ATCC 33173T. The predominant respiratory quinone of strain PYC7WT is Q-9, with Q-8 as a minor component. The major fatty acids are C18 : 1 ω6c and / or C18 : 1 ω7c, C16 : 0, C16 : 1 ω6c and/or C16 : 1 ω7c, and C12 : 0 3OH. The polar lipids of strain PYC7WT include phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylinositol and two unidentified phospholipids. Genome sequencing revealed a genome size of 4.79 Mbp and a G+C content of 62.9 mol%. DNA-DNA hybridization values of strain PYC7WT showed 45, 30 and 38 % relatedness with Halomonas johnsoniae DSM 21197T, Halomonas hamiltonii DSM 21196T and Halomonas stevensii DSM 21198T, respectively. Combining phenotypic, biochemical, genotypic and DNA-DNA hybridization data, we propose that strain PYC7WT represents a novel species within the genus Halomonas and to have the name Halomonas montanilacus sp. nov.; PYC7WT (=CICC 24506T= KCTC 62529T) is the type strain.


Assuntos
Halomonas/classificação , Lagos/microbiologia , Filogenia , Águas Salinas , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Halomonas/isolamento & purificação , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Tibet , Vitamina K 2/análogos & derivados , Vitamina K 2/química
11.
Int J Syst Evol Microbiol ; 70(5): 3406-3412, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32375947

RESUMO

A Gram-stain-positive, strictly aerobic and rod-shaped bacterium, designated as 3 H-10T, was isolated from a yellow water sample collected from the manufacturing process of strong flavor Chinese baijiu in Yibin region of Sichuan province (PR China). Oval endospores were formed at the subtermini of cells with swollen sporangia. The isolate was able to grow at temperatures of 20-45 °C (optimum growth at 37 °C), at pH 6.0-10.0 (optimum growth at pH 8.0) and in the presence of 0-2 % (w/v) NaCl (optimum growth with 0 % NaCl). Ribose was the major cell-wall sugar, and meso-diaminopimelic acid (meso-DAP) was the diagnostic amino acid. The main polar lipids of 3 H-10T included diphosphatidylglycerol (DPG), phosphatidylglycerol (PG) and phosphatidylethanolamine (PE). MK-7 was predominant menaquinone and iso-C15 : 0 (60.7 %) was the major fatty acid. Comparisons of 16S rRNA gene sequence indicated that 3 H-10T was most closely related to Bacillus mesophilus SA4T (96.30 %), Bacillus ginsengihumi Gsoil 114T (96.27 %) and Bacillus shackletonii LMG 18435T (96.27 %). The average nucleotide identity (ANI) values between strain 3 H-10T and the three type strains mentioned above were 69.56, 70.19 and 70.67 %, respectively. The genomic DNA G+C content was 35.4 mol%. On the basis of its phenotypic, chemotaxonomic and phylogenetic properties, strain 3 H-10T represents a novel species of the genus Bacillus, for which the name Bacillus aquiflavi sp. nov. is proposed. The type strain is Bacillus aquiflavi 3 H-10T (=CICC 24755T=JCM 33703T).


Assuntos
Bebidas Alcoólicas/microbiologia , Bacillus/classificação , Filogenia , Bacillus/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , China , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Água
12.
Nano Lett ; 19(11): 7598-7607, 2019 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-31244238

RESUMO

Two-dimensional transition-metal dichalcogenide (2D TMD) layers are highly attractive for emerging stretchable and foldable electronics owing to their extremely small thickness coupled with extraordinary electrical and optical properties. Although intrinsically large strain limits are projected in them (i.e., several times greater than silicon), integrating 2D TMDs in their pristine forms does not realize superior mechanical tolerance greatly demanded in high-end stretchable and foldable devices of unconventional form factors. In this article, we report a versatile and rational strategy to convert 2D TMDs of limited mechanical tolerance to tailored 3D structures with extremely large mechanical stretchability accompanying well-preserved electrical integrity and modulated transport properties. We employed a concept of strain engineering inspired by an ancient paper-cutting art, known as kirigami patterning, and developed 2D TMD-based kirigami electrical conductors. Specifically, we directly integrated 2D platinum diselenide (2D PtSe2) layers of controlled carrier transport characteristics on mechanically flexible polyimide (PI) substrates by taking advantage of their low synthesis temperature. The metallic 2D PtSe2/PI kirigami patterns of optimized dimensions exhibit an extremely large stretchability of ∼2000% without compromising their intrinsic electrical conductance. They also present strain-tunable and reversible photoresponsiveness when interfaced with semiconducting carbon nanotubes (CNTs), benefiting from the formation of 2D PtSe2/CNT Schottky junctions. Moreover, kirigami field-effect transistors (FETs) employing semiconducting 2D PtSe2 layers exhibit tunable gate responses coupled with mechanical stretching upon electrolyte gating. The exclusive role of the kirigami pattern parameters in the resulting mechanoelectrical responses was also verified by a finite-element modeling (FEM) simulation. These multifunctional 2D materials in unconventional yet tailored 3D forms are believed to offer vast opportunities for emerging electronics and optoelectronics.

13.
Respir Res ; 20(1): 131, 2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31242908

RESUMO

BACKGROUND: Patients with acute lung injury (ALI) have increased levels of pro-inflammatory mediators, which impair endothelial progenitor cell (EPC) function. Increasing the number of EPC and alleviating EPC dysfunction induced by pro-inflammatory mediators play important roles in suppressing ALI development. Because the high density lipoprotein reverse-D-4F (Rev-D4F) improves EPC function, we hypothesized that it might repair lipopolysaccharide (LPS)-induced lung damage by improving EPC numbers and function in an LPS-induced ALI mouse model. METHODS: LPS was used to induce ALI in mice, and then the mice received intraperitoneal injections of Rev-D4F. Immunohistochemical staining, flow cytometry, MTT, transwell, and western blotting were used to assess the effect of Rev-D4F on repairment of lung impairment, and improvement of EPC numbers and function, as well as the signaling pathways involved. RESULTS: Rev-D4F inhibits LPS-induced pulmonary edema and decreases plasma levels of the pro-inflammatory mediators TNF-α and ET-1 in ALI mice. Rev-D4F inhibited infiltration of red and white blood cells into the interstitial space, reduced lung injury-induced inflammation, and restored injured pulmonary capillary endothelial cells. In addition, Rev-D4F increased numbers of circulating EPC, stimulated EPC differentiation, and improved EPC function impaired by LPS. Rev-D4F also acted via a PI3-kinase-dependent mechanism to restore levels of phospho-AKT, eNOS, and phospho-eNOS suppressed by LPS. CONCLUSIONS: These findings indicate that Rev-D4F has an important vasculoprotective role in ALI by improving the EPC numbers and functions, and Rev-D4F reverses LPS-induced EPC dysfuncion partially through PI3K/AKT/eNOS signaling pathway.


Assuntos
Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/tratamento farmacológico , Células Progenitoras Endoteliais/efeitos dos fármacos , Lipopolissacarídeos/toxicidade , Peptídeos/uso terapêutico , Lesão Pulmonar Aguda/metabolismo , Animais , Relação Dose-Resposta a Droga , Células Progenitoras Endoteliais/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Peptídeos/farmacologia
14.
Extremophiles ; 22(2): 221-231, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29270851

RESUMO

Halomonas alkalicola CICC 11012s is an alkaliphilic and halotolerant bacterium isolated from a soap-making tank (pH > 10) from a household-product plant. This strain can propagate at pH 12.5, which is fatal to most bacteria. Genomic analysis revealed that the genome size was 3,511,738 bp and contained 3295 protein-coding genes, including a complete cell wall and plasma membrane lipid biosynthesis pathway. Furthermore, four putative Na+/H+ and K+/H+ antiporter genes, or gene clusters, designated as HaNhaD, HaNhaP, HaMrp and HaPha, were identified within the genome. Heterologous expression of these genes in antiporter-deficient Escherichia coli indicated that HaNhaD, an Na+/H+ antiporter, played a dominant role in Na+ tolerance and pH homeostasis in acidic, neutral and alkaline environments. In addition, HaMrp exhibited Na+ tolerance; however, it functioned mainly in alkaline conditions. Both HaNhaP and HaPha were identified as K+/H+ antiporters that played an important role in high alkalinity and salinity. In summary, genome analysis and heterologous expression experiments demonstrated that a complete set of adaptive strategies have been developed by the double extremophilic strain CICC 11012s in response to alkalinity and salinity. Specifically, four antiporters exhibiting different physiological roles for different situations worked together to support the strain in harsh surroundings.


Assuntos
Proteínas de Bactérias/metabolismo , Genoma Bacteriano , Halomonas/genética , Antiportadores de Potássio-Hidrogênio/metabolismo , Trocadores de Sódio-Hidrogênio/metabolismo , Adaptação Fisiológica , Proteínas de Bactérias/genética , Ambientes Extremos , Antiportadores de Potássio-Hidrogênio/genética , Salinidade , Trocadores de Sódio-Hidrogênio/genética
15.
Int J Syst Evol Microbiol ; 67(9): 3150-3155, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28840813

RESUMO

A Gram-stain-negative, rod-shaped, bright-yellow-pigmented bacterium, designated 164T, was isolated from a used sponge for equipment cleaning at a household product plant in China. The 16S rRNA gene sequence comparisons indicated that strain 164T was most closely related to Novosphingobium panipatense DSM 22890T (98.28 % similarity) and shared sequence similarities of 97.73-98.27 % with other members of the genus Novosphingobium. In DNA-DNA hybridization studies the relatedness between strain 164T and its closest phylogenetic neighbours was <70 %, which indicated that strain 164T represented a novel species of the genus Novosphingobium. The DNA G+C content of strain 164T was 65.9 mol%. The major respiratory quinone was ubiquinone Q-10 (83.5 %) with minor amounts of Q-9 (16.5 %). The polar lipid profile included diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidyldimethylethanolamine, sphingoglycolipid, phosphatidylcholine, unidentified aminolipids and unidentified aminophospholipids. Spermidine was the major polyamine. The major fatty acids were summed feature 8 (consisting of C18 : 1ω7c and/or C18 : 1ω6c) and C14 : 0 2-OH. The results obtained from phylogenetic analysis, DNA-DNA hybridization, and chemotaxonomic and phenotypic analysis support the conclusion that strain 164T represents a novel species of the genus Novosphingobium, for which the name Novosphingobium clariflavum sp. nov. is proposed. The type strain is 164T (=CICC 11035sT=DSM 103351T).


Assuntos
Produtos Domésticos , Filogenia , Sphingomonadaceae/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Espermidina/química , Sphingomonadaceae/genética , Sphingomonadaceae/isolamento & purificação , Ubiquinona/química
16.
Int J Syst Evol Microbiol ; 67(5): 1546-1550, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28005522

RESUMO

A Gram-stain-negative, alkaliphilic and moderately halophilic bacterium, designated 56-L4-10aEnT, was isolated from a household product plant in China. Cells of the novel isolate were rod-shaped, non-spore-forming and non-motile. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain 56-L4-10aEnT belongs to the genus Halomonas, with the six closest neighbours being Halomonas mongoliensis Z-7009T (97.59 % 16S rRNA gene sequence similarity), Halomonas ventosae Al12T (97.35 %), Halomonas campaniensis 5AGT (97.22 %), Halomonas alimentaria YKJ-16T (97.22 %), Halomonas shengliensis SL014B-85T (97.12 %) and Halomonas fontilapidosi 5CRT (97.09 %). The main polar lipids of strain 56-L4-10aEnT contained diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. The predominant respiratory quinone was Q-9, with Q-8 as a minor component. The major fatty acids were C18 : 1ω7c/C18 : 1ω6c and C16 : 0. Strain 56-L4-10aEnT was clearly distinguished from the type strains mentioned above through phylogenetic analysis, DNA-DNA hybridization, fatty acid composition data and a range of physiological and biochemical characteristics comparisons. It is evident from the genotypic and phenotypic data that strain 56-L4-10aEnTcould be classified as a representative of a novel species of the genus Halomonas, for which the name Halomonas alkalicola sp. nov. is proposed. The type strain is 56-L4-10aEnT (=CICC 11012sT=DSM 103354T).


Assuntos
Halomonas/classificação , Produtos Domésticos , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , DNA Ribossômico/genética , Ácidos Graxos/química , Genótipo , Halomonas/genética , Halomonas/isolamento & purificação , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
17.
Ear Hear ; 38(6): 647-652, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28471842

RESUMO

Hearing loss (HL) is a common sensory impairment in humans, with significant economic and social impacts. With nearly 20% of the world's population, China has focused on economic development and health awareness to improve the care for its hearing-impaired population. Recently, the Chinese government has initiated national programs such as the China Disabled Persons Federation to fund prevention, treatment, and rehabilitation of hearing impairment. Newborn hearing screening and auditory rehabilitation programs in China have expanded exponentially with government support. While facing many challenges and overcoming obstacles, cochlear implantation (CI) programs in China have also experienced considerable growth. This review discusses the implementation of CI programs for HL in China and presents current HL data including epidemiology, newborn hearing screening, and determination of genetic etiologies. Sharing the experience in Chinese auditory rehabilitation and CI programs will shine a light on the developmental pathway of healthcare infrastructure to meet emerging needs of the hearing-impaired population in other developing countries.


Assuntos
Implante Coclear , Correção de Deficiência Auditiva , Perda Auditiva/reabilitação , China/epidemiologia , Implantes Cocleares , Perda Auditiva/diagnóstico , Perda Auditiva/epidemiologia , Testes Auditivos , Humanos , Recém-Nascido , Triagem Neonatal , Desenvolvimento de Programas
18.
Guang Pu Xue Yu Guang Pu Fen Xi ; 37(1): 267-72, 2017 Jan.
Artigo em Zh | MEDLINE | ID: mdl-30221890

RESUMO

Currently, increasing importance has been attached to heavy metal pollution of water environment. In order to help geologist and environmentalist to obtain on-site experimental data, there is an urgent need to develop portable analysis techniques of water quality, which can be used to give an timely and accurate assessment of water quality of the contaminated area with low cost and to monitor water environment conveniently in daily preventing and controlling work of water pollution. Based on adsorption with Purolite S930 chelating resin at pH 4 and thin-film sample preparation technique, a rapid and simple on-site-oriented analysis method of heavy metal ions, namely Mn, Fe, Ni, Cu, Zn and Pb in aqueous solutions, was developed utilizing a handheld energy-dispersive X-ray fluorescence in this paper. The correlation coefficients of the calibration curves were greater than 0.992 for all six metal ions, the lower limits of detection were between 5.8 and 18.6 µg·L-1. Precision tests carried out on multi-element mixed solutions showed that the relative standard deviations (RSD, n=10) were better than 15%. The method has been used on-site to analysis 21 water samples collected from different river or well sites near a mining area northeast China. Out of the five underground water samples one was found contaminated by Cu and Zn (Class Ⅲ), one by Zn and Fe (Class Ⅱ), and one by Fe(in between Class Ⅱ to Ⅲ). Surface water samples showed better qualities. But two out of the sixteen were found to be contaminated by Mn heavily (Class Ⅳ). Laboratory ICPMS was used to analyze the same samples. The results for Cu, Ni and Pb were coincident with the on-site data in general. But for Zn and Mn with higher concentrations, on-site data were lower than that by ICPMS. The reason for that might be the inclusion of the fine suspending particles in the samples by ICPMS. We conclude that the on-site data were effective. With the described method, an overall data acquisition time, including sampling, processing and measuring, can be within 12 hours for a batch of 10 samples. The pre-concentration device and the XRF instrument are both small, light, portable and can operate without external power supply. So, the method is suitable for on-site water sample analysis, especially in remote areas.

19.
Int J Syst Evol Microbiol ; 66(11): 4723-4728, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27515245

RESUMO

A Gram-stain-positive, facultatively anaerobic, thermophilic bacterium, designated ZQ18-1T, was isolated from a high temperature daqu sample collected from the sesame-flavour liquor-making process. Oval endospores were formed at the centre of cells with swollen sporangia. The isolate was able to grow at temperatures of 20-60 °C (optimum growth at 50 °C), at pH 4-9 (optimum growth at pH 8) and in the presence of 0-10 % (w/v) NaCl (optimum growth with 2 % NaCl). Glucose and galactose were major cell-wall sugars, and meso-diaminopimelic acid was the diagnostic amino acid. The major polar lipids consisted of phosphatidylglycerol, diphosphatidylglycerol and three glycolipids. The major cellular fatty acids were anteiso-C17 : 0 and iso-C16 : 0, and the predominant menaquinone was MK-7. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain ZQ18-1T was most closely related to Scopulibacillus darangshiensis DLS-06T, Pullulanibacillus pueri YN3T, Tuberibacillus calidus 607T, Pullulanibacillus naganoensis ATCC 53909T, Pullulanibacillus uraniitolerans UG-2T, Sporolactobacillus terrae DSM 11697T and Sporolactobacillus inulinus NRIC 1133T. Strain ZQ18-1T showed low DNA-DNA relatedness (40.7, 23.1, 46.5, 27.2, 45.6, 33.7 and 55.1 %) with the strains mentioned above. Based on morphological characteristics, chemotaxonomic characteristics, DNA-DNA hybridization data and physiological properties, strain ZQ18-1T represents a novel species of the genus Scopulibacillus, for which the name Scopulibacillus daqui sp. nov. is proposed. The type strain is Scopulibacillus daqui ZQ18-1T (=DSM 28236T=CICC 10824T). An emended description of the genus Scopulibacillus is provided.


Assuntos
Bacillales/classificação , Microbiologia de Alimentos , Filogenia , Bacillales/genética , Bacillales/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Temperatura Alta , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Esporos Bacterianos , Vitamina K 2/química
20.
Kidney Blood Press Res ; 41(1): 108-18, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26881856

RESUMO

BACKGROUND/AIMS: The mechanism by which angiotensin-converting enzyme inhibitors (ACEIs) attenuate renal fibrosis has not been fully uncovered. METHODS: Renal fibrosis in rats was triggered by unilateral ureteral obstruction (UUO) and treated with Enalapril. RESULTS: Enalapril attenuated renal fibrosis, as evidenced by the fibrosis scores (1.07±0.73 versus 2.18±0.75 for 200 mg/ml Enalapril versus control, p<0.01) of Enalapril-treated UUO rats compared to mock-treated UUO rats. The amelioration was mast cell dependent, as Enalapril exhibited no effects on mast cell-deficient Kit(wsh/wsh) mice developing renal fibrosis. We detected lower levels of transforming growth factor ß (TGF-ß) and alpha-smooth muscle actin (α-SMA, a fibroblast activation marker) in the kidney tissue of Enalapril-treated UUO rats relative to the control UUO rats. Enalapril-treated UUO rats exhibited far fewer mast cells infiltrating per area in the kidney tissue than the control UUO rats (8.00±0.65 versus 29.00±0.57, p<0.01). Electron microscopy images revealed that mast cell degranulation was inhibited by Enalapril treatment. Further, IgE-mediated passive cutaneous anaphylaxis demonstrated that Enalapril blocked mast cell degranulation in vivo. CONCLUSION: Enalapril attenuated renal fibrosis in UUO rats, possibly by a mechanism involving the suppression of mast cell degranulation.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Degranulação Celular/efeitos dos fármacos , Nefropatias/tratamento farmacológico , Nefropatias/patologia , Mastócitos/efeitos dos fármacos , Mastócitos/patologia , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Animais , Degranulação Celular/fisiologia , Fibrose , Masculino , Camundongos , Ratos , Ratos Sprague-Dawley
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