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1.
J Transl Med ; 21(1): 657, 2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37740205

RESUMO

BACKGROUND: Increasing evidence has linked the thyroid dysfunction to the pathogenesis of dementia. Evidence from clinical studies has demonstrated that hypothyroidism is related to an increased risk of dementia. But the association of hyperthyroidism with dementia is largely unknown. METHODS: We used the adenovirus containing thyrotropin receptor (TSHR) amino acid residues 1-289 (Ad-TSHR289)-induced Graves' disease (GD) phenotype in Alzheimer's disease (AD) model mice (APP/PS1 mice) to evaluate the effect of hyperthyroidism on the cognitive function and ß-amyloid (Aß) accumulation. RESULTS: GD mice exhibited a stable long-term hyperthyroidism and cognitive deficits. Single Cell RNA-sequencing analysis indicated that microglia function played a critical role in the pathophysiological processes in GD mice. Neuroinflammation and polarization of microglia (M1/M2 phenotype) and activated receptor-interacting serine/threonine protein kinase 3 (RIPK3)/mixed lineage kinase domain-like pseudo-kinase (MLKL)-mediated necroptosis contributed to the pathological process, including Aß deposition and neuronal loss. RIPK3 inhibitor could inhibit GD-mediated Aß accumulation and neuronal loss. CONCLUSIONS: Our findings reveal that GD hyperthyroidism aggravates cognitive deficits in AD mice and induces Aß deposition and neuronal loss by inducing neuroinflammation and RIPK3/MLKL-mediated necroptosis.


Assuntos
Doença de Alzheimer , Doença de Graves , Hipertireoidismo , Animais , Camundongos , Necroptose , Doenças Neuroinflamatórias , Hipertireoidismo/complicações , Cognição , Doença de Alzheimer/complicações
2.
Chem Sci ; 14(7): 1781-1786, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36819861

RESUMO

Organic-inorganic halide perovskites (OIHPs) are very eye-catching due to their chemical tunability and rich physical properties such as ferroelectricity, magnetism, photovoltaic properties and photoluminescence. However, no nickel-based OIHP ferroelectrics have been reported so far. Here, we designed an ABX3 OIHP ferroelectric (3-pyrrolinium)NiCl3, where the 3-pyrrolinium cations are located on the voids surrounded by one-dimensional chains composed of NiCl6-face-sharing octahedra via hydrogen bonding interactions. Such a unique structure enables the (3-pyrrolinium)NiCl3 with a high spontaneous polarization (P s) of 5.8 µC cm-2 and a high Curie temperature (T c) of 428 K, realizing dramatic enhancement of 112 and 52 K compared to its isostructural (3-pyrrolinium)MCl3 (M = Cd, Mn). To our knowledge, remarkably, (3-pyrrolinium)NiCl3 should be the first case of nickel(ii)-based OIHP ferroelectric to date, and its T c of 428 K (35 K above that of BaTiO3) is the highest among all reported one-dimensional OIHP ferroelectrics. This work offers a new structural building block for enriching the family of OIHP structures and will inspire the further exploration of new nickel(ii)-based OIHP ferroelectrics.

3.
Appl Biochem Biotechnol ; 195(3): 1644-1655, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36355336

RESUMO

Cisplatin broadly functions as a routine treatment for lung adenocarcinoma (LUAD) patients. However, primary and acquired cisplatin resistances frequently occur in the treatment of LUAD patients, seriously affecting the therapeutic effect of cisplatin in patients. We intended to illustrate the impact of let-7c-5p/cell division cycle 25A (CDC25A) axis on cisplatin resistance in LUAD. Expression of let-7c-5p and CDC25A was analyzed via quantitative real-time polymerase chain reaction. The interaction between the two was verified by dual-luciferase reporter detection. For detecting half-maximal inhibitory concentration value of cisplatin in LUAD cells and cell proliferation, we separately applied Cell Counting Kit-8 and colony formation assays. Furthermore, we measured cell apoptosis and cell cycle distribution via flow cytometry, as well as cell cycle-related protein expression via Western blot. Let-7c-5p was evidently downregulated in LUAD, while CDC25A was remarkably upregulated. Let-7c-5p upregulation arrested LUAD cells to proliferate, stimulated cell apoptosis, and arrested cell cycle in G0/G1 phase, thus enhancing sensitivity of LUAD cells to cisplatin. In terms of mechanism, CDC25A was directly targeted by let-7c-5p, and the influence of let-7c-5p overexpression on LUAD proliferation, apoptosis, cell cycle, and cisplatin resistance could be reversed by CDC25A upregulation. Let-7c-5p improved sensitivity of LUAD cells to cisplatin by modulating CDC25A, and let-7c-5p/CDC25A axis was an underlying target for the intervention of LUAD cisplatin resistance.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , MicroRNAs , Humanos , Cisplatino/farmacologia , MicroRNAs/genética , MicroRNAs/metabolismo , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/metabolismo , Proliferação de Células , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Fosfatases cdc25/genética , Fosfatases cdc25/metabolismo , Fosfatases cdc25/farmacologia
4.
Front Pharmacol ; 13: 1013218, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36438823

RESUMO

Accumulating evidence has demonstrated that metformin improved hypertriglyceridemia. The present study aim to investigate the molecular mechanism by which metformin improves hypertriglyceridemia via regulation of diacylglycerol O-acyltransferase 2 (DGAT2) and X-box binding protein 1 (XBP1) in the liver and whether AMP-activated protein kinase (AMPK) is involved. Mice were fed a high-fat diet (HFD) or high-fat diet with metformin for 5 weeks to evaluate the effect of metformin on triglyceride (TG) levels and expression of DGAT2 and XBP1 in the liver. In vitro HepG2 cells or XBP1 knockout AML12 hepatocytes were stimulated with metformin, palmitic acid or small interfering RNA inducing XBP1 knockdown, or dominant-negative mutant AMPK plasmid. Metformin treatment reduced hepatic TG levels in the liver of HFD-fed mice. Expression of nuclear and cytoplasmic XBP1 protein and its downstream target gene DGAT2 decreased in the liver of HFD-fed mice and HepG2 cells after metformin treatment. AMPK inactivation or overexpression of XBP1 attenuates this effect. Our preliminary results demonstrate that metformin activates AMPK to reduce TG synthesis by inhibiting the XBP1-mediated DGAT2 pathway, at least in part, suggesting that XBP1 is a new metabolic mediator for metformin treatment of hypertriglyceridemia and associated metabolic disease.

5.
Am J Transl Res ; 14(3): 1901-1908, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35422950

RESUMO

OBJECTIVE: To explore the therapeutic efficacy of the levonorgestrel-releasing intrauterine system combined with turtle shell decocted pills for endometriosis and their effect on cellular immune function. METHODS: Clinical data of 118 patients with endometriosis admitted to Taizhou First People's Hospital from January 2019 to January 2020 were retrospectively analyzed. The patients were assigned into a single-drug group (n=68) and a combined traditional Chinese medicine group (n=50) according to treatment methods. The single-drug group was treated with the levonorgestrel-releasing intrauterine system, and the combined traditional Chinese medicine group was treated with additional turtle shell decocted pills for three cycles for a total of 12 weeks. Enzyme-linked immunosorbent assay was adopted to measure the concentration of Th1 cytokines (tumor necrosis factor (TNF)-α and interferon (IFN)-γ) and Th2 cytokines (interleukin (IL)-6 and IL-10), and the protein level of programmed cell death 1 (PD-1) and programmed cell death ligand 1 (PD-L1). The levels of serum luteinizing hormone (LH), follicle stimulating hormone (FSH), and estradiol (E2) were compared between the two groups. The response rate of treatment, the control rate of blood pressure and the incidence of adverse reactions were recorded in both groups. RESULTS: The response rate of treatment in the combined traditional Chinese medicine group was higher than that in the single-drug group (P<0.05). Compared to before treatment, the TNF-α and IFN-γ increased in both groups after treatment, and the expressions were higher in the combined traditional Chinese medicine group than in the single-drug group (all P<0.05). After treatment, the levels of IL-6, IL-10, PD-1, and PD-L1 decreased, and the decreases in the combined traditional Chinese medicine group were greater than those in the single-drug group (all P<0.05). Serum LH, FSH and E2 levels before and after the treatment in the two groups were not statistically different (all P>0.05). The incidence of treatment-related adverse reactions between the two groups of patients was also not statistically different (P>0.05). CONCLUSION: Turtle shell decocted pills can increase the clinical efficacy of levonorgestrel-releasing intrauterine system in the treatment of endometriosis, reduce levels of PD-1, and PD-L1 and improve cellular immune function. The pills do not affect the secretion of ovarian hormones or increase adverse reactions.

6.
J Clin Endocrinol Metab ; 106(8): e2953-e2967, 2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-33822100

RESUMO

CONTEXT: Data quantifying the impact of metreleptin therapy on survival in non-human immunodeficiency virus (HIV)-related generalized lipodystrophy (GL) and partial lipodystrophy (PL) are unavailable. OBJECTIVE: This study aimed to estimate the treatment effect of metreleptin on survival in patients with GL and PL. DESIGN/SETTING/PATIENTS: Demographic and clinical characteristics were used to match metreleptin-treated and metreleptin-naïve patients with GL and PL. Differences in mortality risk were estimated between matched cohorts of metreleptin-treated and metreleptin-naïve patient cohorts using Cox proportional hazard models. Sensitivity analyses assessed the impact of study assumptions and the robustness of results. OUTCOME MEASURES: This study assessed time-to-mortality and risk of mortality. RESULTS: The analysis evaluated 103 metreleptin-naïve patients with characteristics matched to 103 metreleptin-treated patients at treatment initiation. Even after matching, some metabolic and organ abnormalities were more prevalent in the metreleptin-treated cohort due to bias toward treating more severely affected patients. A Cox proportional hazards model associated metreleptin therapy with an estimated 65% decrease in mortality risk (hazard ratio [HR] 0.348, 95% confidence interval (CI): 0.134-0.900; P = 0.029) even though the actual number of events were relatively small. Results were robust across a broad range of alternate methodological assumptions. Kaplan-Meier estimates of time-to-mortality for the metreleptin-treated and the matched metreleptin-naïve cohorts were comparable. CONCLUSIONS: Metreleptin therapy was associated with a reduction in mortality risk in patients with lipodystrophy syndromes despite greater disease severity in treated patients, supporting the view that metreleptin can have a positive disease-modifying impact. Confirmatory studies in additional real-world and clinical datasets are warranted.


Assuntos
Leptina/análogos & derivados , Lipodistrofia Generalizada Congênita/tratamento farmacológico , Lipodistrofia/tratamento farmacológico , Adolescente , Adulto , Criança , Estudos de Coortes , Feminino , Humanos , Leptina/uso terapêutico , Lipodistrofia/mortalidade , Lipodistrofia Generalizada Congênita/mortalidade , Masculino , Taxa de Sobrevida , Resultado do Tratamento , Adulto Jovem
8.
J Hazard Mater ; 393: 122394, 2020 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-32114135

RESUMO

The global expansion and intensification of toxic cyanobacterial blooms require effective algaecides. Algaecides should be selective, effective, fast-acting, and ideally suppress cyanotoxin production. In this study, whether both maximum growth suppression and minimal toxin production can be simultaneously achieved was tested with a selective algaecide H2O2, through its ability to induce apoptosis-like programmed cell death (AL PCD) in a common bloom species Microcystis aeruginosa. Under doses of 1-15 mg L-1, non-monotonic dose-response suppression of H2O2 on M. aeruginosa were observed, where maximal cell death and minimal microcystin production both occurred at a moderate dose of 10 mg L-1 H2O2. Maximal cell death was indeed achieved through AL PCD, as revealed by integrated biochemical, structural, physiological and transcriptional evidence; transcriptional profile suggested AL PCD was mediated by mazEF and lexA systems. Higher H2O2 doses directly led to necrosis in M. aeruginosa, while lower doses only caused recoverable stress. The integrated data showed the choice between the two modes of cell death is determined by the intracellular energy state under stress. A model was proposed for suppressing M. aeruginosa with AL PCD or necrosis. H2O2 was demonstrated to simultaneously maximize the suppression of both growth and microcystin production through triggering AL PCD.


Assuntos
Herbicidas/farmacologia , Peróxido de Hidrogênio/farmacologia , Microcystis/efeitos dos fármacos , Trifosfato de Adenosina/metabolismo , Apoptose/efeitos dos fármacos , Eutrofização , Toxinas Marinhas/biossíntese , Microcistinas/biossíntese , Microcystis/crescimento & desenvolvimento , Microcystis/metabolismo , Fotossíntese/efeitos dos fármacos
9.
Appl Opt ; 58(17): 4720-4725, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31251294

RESUMO

Surface-enhanced Raman scattering (SERS) has powerful capabilities in the field of environmental analysis and biological diagnostics because of its instinctive properties of high sensitivity and label-free detection. However, the fabrication of SERS substrate requires complicated processes and expensive equipment. This paper proposes a simple method approach to synthesize a 3D SERS substrate via electroless galvanic replacement reaction inside a microfluidic channel. Copper microparticles are assembled in a microfluidic channel, and silver nitrate solution is pumped into the channel to in situ produce the silver nanoparticles (Ag NPs) on the surface of copper microparticles. Because the copper particles occupy the channel by stack, the 3D Cu@AgNP SERS substrate can be obtained. The probing molecule (methylene blue) was utilized to investigate with the limit of detection (1×10-7 M). The biological molecules (urea and melamine) have been used to demonstrate its benefits in medical applications, and cancer cell detection has been implemented to demonstrate its benefits in cell biology. In addition, the device can filter and wash cells, forming a simple and fast filter. Our work on this simple fabrication method of active SERS substrate has great value for medical and biological applications.

10.
PLoS One ; 13(8): e0203129, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30153296

RESUMO

OBJECTIVE: We intended to establish the threshold for anti-Mullerian hormone (AMH) in the diagnosis of polycystic ovary syndrome (PCOS) in China. METHODS: A total of 771 women (653 with PCOS and 118 healthy controls) were enrolled. The serum AMH, follicle-stimulating hormone (FSH), luteinizing hormone (LH), FSH/LH, prolactin, estradiol, testosterone (T), dehydroepiandrosterone sulfate (DHEA-S), sex hormone-binding globulin (SHBG), 17α-OH progesterone (17α-OHP), fasting insulin (INS), fasting glucose, free androgen index (FAI%) and homeostasis model assessment for insulin resistance (HOMA-IR) index were analyzed, and the diagnostic utility of AMH, LH/FSH, T and INS was established using receiver operator characteristic (ROC) curves. With AMH, LH/FSH, T and INS as independent variables, a logistic regression model was established, and the ROC curve for combined detection was fitted with the probability value of the model. RESULTS: The serum level of FSH, LH, LH/FSH, AMH, FAI%, 17α-OHP, fasting INS, T, SHBG, DHEA-S and HOMA-IR were altered in the PCOS patients. The best compromise between sensitivity and specificity was found at an AMH cut-off level of 8.16 ng/ml and 5.89 ng/ml for the age groups 20-29 and 30-39 years, with the corresponding area under the curve being 0.846 and 0.865 respectively. The area under the ROC curve for combined detection was 0.951, which was significantly greater than that of each index. Finally, the concentration of AMH was associated with FSH, LH, LH/FSH, T, and ovarian volume in PCOS patients. CONCLUSION: The optimal AMH diagnostic threshold for PCOS was 8.16 ng/ml (20-29 years) and 5.89 ng/ml (30-39 years) in the Chinese population of this study. Moreover, serum AMH, LH/FSH, T and INS could be used in combination to improve the diagnostic specificity and sensitivity for the detection of PCOS.


Assuntos
Hormônio Antimülleriano/sangue , Síndrome do Ovário Policístico/sangue , Adulto , Fatores Etários , Área Sob a Curva , Biomarcadores/sangue , China , Feminino , Humanos , Modelos Biológicos , Síndrome do Ovário Policístico/diagnóstico por imagem , Probabilidade , Curva ROC , Estudos Retrospectivos , Adulto Jovem
11.
Int J Nanomedicine ; 10: 4309-19, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26170666

RESUMO

A novel biocompatible and biodegradable drug-delivery nanoparticle (NP) has been developed to minimize the severe side effects of the poorly water-soluble anticancer drug paclitaxel (PTX) for clinical use. PTX was loaded into the hydrophobic cavity of a hydrophilic cyclodextrin derivative, heptakis (2,6-di-O-methyl)-ß-cyclodextrin (DM-ß-CD), using an aqueous solution-stirring method followed by lyophilization. The resulting PTX/DM-ß-CD inclusion complex dramatically enhanced the solubility of PTX in water and was directly incorporated into chitosan (CS) to form NPs (with a size of 323.9-407.8 nm in diameter) using an ionic gelation method. The formed NPs had a zeta potential of +15.9-23.3 mV and showed high colloidal stability. With the same weight ratio of PTX to CS of 0.7, the loading efficiency of the PTX/DM-ß-CD inclusion complex-loaded CS NPs was 30.3-fold higher than that of the PTX-loaded CS NPs. Moreover, it is notable that PTX was released from the DM-ß-CD/CS NPs in a sustained-release manner. The pharmacokinetic studies revealed that, compared with reference formulation (Taxol(®)), the PTX/DM-ß-CD inclusion complex-loaded CS NPs exhibited a significant increase in AUC(0→24h) (the area under the plasma drug concentration-time curve over the period of 24 hours) and mean residence time by 2.7-fold and 1.4-fold, respectively. Therefore, the novel drug/DM-ß-CD inclusion complex-loaded CS NPs have promising applications for the significantly improved delivery and controlled release of the poorly water-soluble drug PTX or its derivatives, thus possibly leading to enhanced therapeutic efficacy and less severe side effects.


Assuntos
Quitosana/química , Nanopartículas/química , Paclitaxel , beta-Ciclodextrinas , Animais , Masculino , Paclitaxel/sangue , Paclitaxel/química , Paclitaxel/farmacocinética , Ratos , Ratos Wistar , beta-Ciclodextrinas/sangue , beta-Ciclodextrinas/química , beta-Ciclodextrinas/farmacocinética
12.
Phys Med Biol ; 59(13): 3373-88, 2014 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-24874943

RESUMO

We developed and investigated a positron emission tomography (PET) system for use with on-line (both in-beam and intra-fraction) image-guided adaptive proton therapy applications. The PET has dual rotating depth-of-interaction measurable detector panels by using solid-state photomultiplier (SSPM) arrays and LYSO scintillators. It has a 44 mm diameter trans-axial and 30 mm axial field-of-view (FOV). A 38 mm diameter polymethyl methacrylate phantom was placed inside the FOV. Both PET and phantom axes were aligned with a collimated 179.2 MeV beam. Each beam delivered ∼50 spills (0.5 s spill and 1.5 s inter-spill time, 3.8 Gy at Bragg peak). Data from each beam were acquired with detectors at a given angle. Nine datasets for nine beams with detectors at nine different angles over 180° were acquired for full-tomographic imaging. Each dataset included data both during and 5 min after irradiations. The positron activity-range was measured from the PET image reconstructed from all nine datasets and compared to the results from simulated images. A (22)Na disc-source was also imaged after each beam to monitor the PET system's performance. PET performed well except for slight shifts of energy photo-peak positions (<1%) after each beam, due mainly to the neutron exposure of SSPM that increased the dark-count noise. This minor effect was corrected offline with a shifting 350-650 keV energy window for each dataset. The results show a fast converging of activity-ranges measured by the prototype PET with high sensitivity and uniform resolution. Sub-mm activity-ranges were achieved with minimal 6 s acquisition time and three spill irradiations. These results indicate the feasibility of PET for intra-fraction beam-range verification. Further studies are needed to develop and apply a novel clinical PET system for on-line image-guided adaptive proton therapy.


Assuntos
Imagens de Fantasmas , Tomografia por Emissão de Pósitrons/instrumentação , Terapia com Prótons/instrumentação , Radioterapia Guiada por Imagem/instrumentação , Estudos de Viabilidade , Processamento de Imagem Assistida por Computador
13.
Antonie Van Leeuwenhoek ; 103(1): 23-36, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22843287

RESUMO

Bacterial and archaeal diversity in surface soils of three coal-fire vents was investigated by T-RFLP analysis and clone libraries of 16S rRNA genes. Soil analysis showed that underground coal fires significantly influenced soil pH, moisture and NO(3) (-) content but had little effect on other elements, organic matter and available nutrients. Hierarchical cluster analysis showed that bacterial community patterns in the soils were very similar, but abundance varied with geographic distance. A clone library from one soil showed that the bacterial community was mainly composed of Firmicutes, Proteobacteria, Acidobacteria, Bacteroidetes, Planctomycetes, Actinobacteria, and unidentified groups. Of these, Firmicutes was the most abundant, accounting for 71.4 % of the clones, and was mainly represented by the genera Bacillus and Paenibacillus. Archaeal phylotypes were closely related to uncultivated species of the phyla Crenarchaeota (97.9 % of clones) and Thaumarchaeota (2.1 %). About 28 % of archaeal phylotypes were associated with ammonia oxidization, especially phylotypes that were highly related to a novel, ammonia-oxidizing isolate from the phylum Thaumarchaeota. These results suggested that microbial communities in the soils were diverse and might contain a large number of novel cultivable species with the potential to assimilate materials by heterotrophic metabolism at high temperature.


Assuntos
Archaea/classificação , Archaea/isolamento & purificação , Bactérias/classificação , Bactérias/isolamento & purificação , Biodiversidade , Microbiologia do Solo , Archaea/genética , Bactérias/genética , China , Clonagem Molecular , Análise por Conglomerados , DNA Arqueal/química , DNA Arqueal/genética , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Genes de RNAr , Dados de Sequência Molecular , Filogenia , Polimorfismo de Fragmento de Restrição , RNA Arqueal/genética , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico , Solo/química
14.
Wei Sheng Wu Xue Bao ; 52(4): 505-11, 2012 Apr 04.
Artigo em Chinês | MEDLINE | ID: mdl-22799216

RESUMO

OBJECTIVE: Establishing a new method of microbial prospecting for oil and gas based on microbial community metabolic function. METHODS: In this study, 45 shallow reservoir soil samples and 25 non-reservoir soil samples were collected. Carbon catabolic activity of the microbial community was measured by biolog microplate, and microbial anomaly of reservoir was judged by discriminant function. RESULT: We screened 10 typical carbon sources of 95 carbon sources which could reflect the differences of reservoir and non-reservoir soil microbial community structure and made the validation test set to experimental zone and controlled zone samples using the discriminant function. The discriminate rate of reservoir and non-reservoir were 97.8% and 100% respectively and the overall accuracy was 98.6%. CONCLUSION: Biolog technology provided a highly efficient and precise method for preliminarily predicting oil and gas reservoir.


Assuntos
Carbono/análise , Carbono/metabolismo , Microbiologia do Solo , Gases/química , Óleos/química
15.
Appl Microbiol Biotechnol ; 94(6): 1521-32, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22391969

RESUMO

Violacein (Vio) is an important purple pigment with many potential bioactivities. Deoxyviolacein, a structural analog of Vio, is always synthesized in low concentrations with Vio in wild-type bacteria. Due to deoxyviolacein's low production and difficulties in isolation and purification, little has been learned regarding its function and potential applications. This study was the first effort in developing a stable and efficient biosynthetic system for producing pure deoxyviolacein. A recombinant plasmid with vioabce genes was constructed by splicing using an overlapping extension-polymerase chain reaction, based on the Vio-synthesizing gene cluster of vioabcde, originating from Duganella sp. B2, and was introduced into Citrobacter freundii. With the viod gene disrupted in the Vio synthetic pathway, Vio production was completely abolished and the recombinant C. freundii synthesized only deoxyviolacein. Interestingly, vioe gene expression was strongly stimulated in the viod-deleted recombinant strain, indicating that viod disruptions could potentially induce polar effects upon the downstream vioe gene within this small operon. Deoxyviolacein production by this strain reached 1.9 g/L in shaker flasks. The product exhibited significant acid/alkali and UV resistance as well as significant inhibition of hepatocellular carcinoma cell proliferation at low concentrations of 0.1-1 µM. These physical characteristics and antitumor activities of deoxyviolacein contribute to illuminating its potential applications.


Assuntos
Vias Biossintéticas , Citrobacter freundii/metabolismo , Indóis/metabolismo , Pigmentos Biológicos/biossíntese , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Citrobacter freundii/genética , Humanos , Indóis/química , Indóis/farmacologia , Estrutura Molecular , Família Multigênica , Pigmentos Biológicos/química , Pigmentos Biológicos/farmacologia
16.
Braz. j. microbiol ; 42(1): 41-45, Jan.-Mar. 2011. ilus
Artigo em Inglês | LILACS | ID: lil-571372

RESUMO

The succession and growth strategy of a spring microbial community under earthquake action were investigated. The majority of pre-earthquake isolates belonged to the Gammaproteobacteria, including two numerically dominant Stenotrophomonas sp. RB25 and Acinetobacter sp. RB11 (r-strategists). The predominant post-earthquake isolates were Alphaproteobacteria, with Rhizobium sp. RA42 (K-strategists) being dominant among these organisms.


Assuntos
Crescimento Bacteriano , Biota , Terremotos , Microbiologia Ambiental , Infecções por Bactérias Gram-Negativas , Gammaproteobacteria/isolamento & purificação , Rhizobium/isolamento & purificação , Stenotrophomonas/isolamento & purificação , Métodos , Estratégias de Saúde , Métodos
17.
Int J Syst Evol Microbiol ; 61(Pt 1): 194-200, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20190023

RESUMO

A halophilic, filamentous actinomycete strain, designated YIM 93246(T), was isolated from a salt lake in Xinjiang province, north-west China, and subjected to polyphasic taxonomic characterization. The isolate grew in the presence of 7-23 % (w/v) NaCl, but not in the absence of NaCl. Strain YIM 93246(T) had particular morphological properties, forming aerial mycelium that had long spore chains and pseudosporangium-like, rhiziform spore aggregates at maturity. LL-DAP was the cell-wall diamino acid and glucosamine, mannose, glucose, arabinose and galactose were the cell-wall sugars. The major fatty acids were iso-C(16 : 0), anteiso-C(15 : 0) and anteiso-C(17 : 0). MK-9 (H(4)) was the predominant menaquinone and the genomic DNA G+C content was 70.5 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain YIM 93246(T) clustered with the genus Jiangella. The sequence similarities between strain YIM 93246(T) and Jiangella alba, Jiangella gansuensis and Jiangella alkaliphila were 96.9, 96.9 and 96.6 %, respectively. Based on morphological, physiological and chemotaxonomic differences, and phylogenetic analysis, a novel genus and species, Haloactinopolyspora alba gen. nov., sp. nov., is proposed. The type strain of the species is YIM 93246(T) (=DSM 45211(T)=KCTC 19409(T)). Additionally, phylogenetic analysis placed the genus Jiangella together with strain YIM 93246(T) within the order Actinomycetales as an independent lineage, clearly distinguished from other described suborders of the class Actinobacteria. Hence, based on phylogenetic characteristics, the genus Jiangella together with the newly proposed genus Haloactinopolyspora are proposed to be classified as Jiangellaceae fam. nov. and Jiangellineae subord. nov.


Assuntos
Actinomycetales/classificação , Actinomycetales/isolamento & purificação , Microbiologia da Água , Actinomycetales/genética , Actinomycetales/fisiologia , Composição de Bases , Parede Celular/química , China , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Ácido Diaminopimélico/análise , Ácidos Graxos/análise , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Cloreto de Sódio/metabolismo , Esporos Bacterianos/citologia , Vitamina K 2/análise
18.
Int J Syst Evol Microbiol ; 61(Pt 7): 1693-1698, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20729305

RESUMO

Three actinomycetal strains, designated YIM 90479, YIM 90480(T) and YIM 90600(T), were isolated from a salt field in Xinjiang province, North-west China and subjected to polyphasic taxonomic study. All three strains were moderately halophilic and were able to grow on agar at NaCl concentrations of up to 20-25 % (w/v). No growth was observed in the absence of NaCl. Good growth occurred at 37 °C and 15 % (w/v) NaCl. The cell walls of the three strains were of the type IV variety and their phospholipid patterns were type PIII. MK-9 (H(4)) and MK-10 (H(4)) or MK-9 (H(4)) and MK-9 (H(2)) were the predominant menaquinones. iso-C(16 : 0) and anteiso-C(17 : 0) or anteiso-C(15 : 0) and anteiso-C(17 : 0) were the major fatty acids. The G+C contents of the genomic DNA were 66.4-68.3 mol%. Based on differential phenotypic, chemotaxonomic and phylogenetic characteristics and the results of DNA-DNA hybridization tests, the three novel stains represent two novel species, for which the names Actinopolyspora alba sp. nov. and Actinopolyspora erythraea sp. nov. are proposed. The type strains of the species are YIM 90480(T) ( = DSM 45004(T)  = KCTC 19119(T)) and YIM 90600(T) ( = CCTCC M 208247(T)  = KCTC 19372(T)). In addition, we propose that Actinopolyspora iraqiensis (Ruan et al., 1994) be transferred to the genus Saccharomonospora as a heterotypic synonym of Saccharomonospora halophila based on present research results.


Assuntos
Actinomycetales/classificação , Filogenia , Microbiologia do Solo , Actinomycetales/genética , Actinomycetales/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Sais/química , Análise de Sequência de DNA , Vitamina K 2/química
19.
Int J Syst Evol Microbiol ; 60(Pt 9): 2113-2119, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19854874

RESUMO

A Gram-staining-positive, facultatively anaerobic, non-motile and moderately halophilic actinobacterium, designated YIM 93306(T), was isolated from a salt lake in Xinjiang province, north-west China, and subjected to a polyphasic taxonomic study. Strain YIM 93306(T) grew in the presence of 2-16 % (w/v) NaCl and did not grow without NaCl. The peptidoglycan type was A4alpha with an l-Lys-l-Glu interpeptide bridge. The whole-cell sugars were glucosamine, arabinose, mannose and two unknown sugars. The predominant menaquinone was MK-8(H(4)). The major fatty acids were iso-C(15 : 0), anteiso-C(15 : 0) and anteiso-C(17 : 0). The polar lipids comprised diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, one unknown phosphoglycolipid and one unknown phospholipid. The DNA G+C content was 68.3 mol%. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain YIM 93306(T) fell within the radius of the suborder Micrococcineae. Its closest phylogenetic neighbour was the type strain of Ruania albidiflava (AS 4.3142(T); 96.2 % 16S rRNA gene sequence similarity), the sole recognized species of the genus Ruania. Sequence similarities between strain YIM 93306(T) and members of other genera of the suborder Micrococcineae were <95.2 %. On the basis of phylogenetic analysis, phenotypic characteristics and chemotaxonomic differences, a novel genus and species, Haloactinobacterium album gen. nov., sp. nov., is proposed. The type strain of the species is YIM 93306(T) (=DSM 21368(T) =KCTC 19413(T) =CCTCC AB 208069(T)). Based on phylogenetic characteristics and 16S rRNA gene signature nucleotide patterns, the genera Ruania and Haloactinobacterium gen. nov. are proposed to belong to a novel family, Ruaniaceae fam. nov.


Assuntos
Actinobacteria/classificação , Actinobacteria/isolamento & purificação , Cloreto de Sódio/metabolismo , Actinobacteria/genética , Actinobacteria/metabolismo , DNA Bacteriano/genética , DNA Ribossômico/genética , Ácidos Graxos/metabolismo , Água Doce/microbiologia , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética
20.
Int J Syst Evol Microbiol ; 60(Pt 9): 2154-2158, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19880632

RESUMO

A novel halophilic, filamentous actinomycete strain, designated YIM 93221(T), was isolated from a salt lake in Xinjiang province, north-west China, and subjected to a polyphasic taxonomic characterization. The isolate grew with 9-23 % (w/v) NaCl and did not grow without NaCl. The isolate formed spiny aerial mycelium and did not form spores at maturity. The isolate contained meso-diaminopimelic acid as the diagnostic diamino acid and glucose, glucosamine, mannose and an unknown sugar as the major whole-cell sugars. The phospholipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannosides and an unknown phospholipid. MK-8(H(4)) was the predominant menaquinone. The major fatty acid was iso-C(16 : 0). The DNA G+C content was 68.1 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain YIM 93221(T) formed a distinct lineage within the suborder Pseudonocardineae and showed 91.9-94.8 % 16S rRNA gene sequence similarity with members of the suborder Pseudonocardineae. On the basis of the evidence from this polyphasic study, a novel genus and species, Haloechinothrix alba gen. nov., sp. nov., are proposed. The type strain of Haloechinothrix alba is YIM 93221(T) (=DSM 45207(T) =CCTCC AB 208140(T)).


Assuntos
Actinomycetales/classificação , Actinomycetales/isolamento & purificação , Água Doce/microbiologia , Cloreto de Sódio/metabolismo , Actinobacteria/classificação , Actinobacteria/genética , Actinobacteria/isolamento & purificação , Actinobacteria/metabolismo , Actinomycetales/genética , Actinomycetales/metabolismo , Técnicas de Tipagem Bacteriana , China , DNA Bacteriano/genética , DNA Ribossômico/genética , Ácidos Graxos/metabolismo , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética
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