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1.
Plant J ; 114(5): 1001-1013, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36705504

RESUMEN

Chromatin modifications shape the epigenome and are essential for gene expression reprogramming during plant development and adaptation to the changing environment. Chromatin modification enzymes require primary metabolic intermediates such as S-adenosyl-methionine, acetyl-CoA, alpha-ketoglutarate, and NAD+ as substrates or cofactors. The availability of the metabolites depends on cellular nutrients, energy and reduction/oxidation (redox) states, and affects the activity of chromatin regulators and the epigenomic landscape. The changes in the plant epigenome and the activity of epigenetic regulators in turn control cellular metabolism through transcriptional and post-translational regulation of metabolic enzymes. The interplay between metabolism and the epigenome constitutes a basis for metabolic control of plant growth and response to environmental changes. This review summarizes recent advances regarding the metabolic control of plant chromatin regulators and epigenomes, which are involved in plant adaption to environmental stresses.


Asunto(s)
Epigénesis Genética , Epigenoma , Cromatina , Oxidación-Reducción
2.
Molecules ; 29(5)2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38474620

RESUMEN

Hyperlipidemia, characterized by elevated serum lipid concentrations resulting from lipid metabolism dysfunction, represents a prevalent global health concern. Ginsenoside Rb1, compound K (CK), and 20(S)-protopanaxadiol (PPD), bioactive constituents derived from Panax ginseng, have shown promise in mitigating lipid metabolism disorders. However, the comparative efficacy and underlying mechanisms of these compounds in hyperlipidemia prevention remain inadequately explored. This study investigates the impact of ginsenoside Rb1, CK, and PPD supplementation on hyperlipidemia in rats induced by a high-fat diet. Our findings demonstrate that ginsenoside Rb1 significantly decreased body weight and body weight gain, ameliorated hepatic steatosis, and improved dyslipidemia in HFD-fed rats, outperforming CK and PPD. Moreover, ginsenoside Rb1, CK, and PPD distinctly modified gut microbiota composition and function. Ginsenoside Rb1 increased the relative abundance of Blautia and Eubacterium, while PPD elevated Akkermansia levels. Both CK and PPD increased Prevotella and Bacteroides, whereas Clostridium-sensu-stricto and Lactobacillus were reduced following treatment with all three compounds. Notably, only ginsenoside Rb1 enhanced lipid metabolism by modulating the PPARγ/ACC/FAS signaling pathway and promoting fatty acid ß-oxidation. Additionally, all three ginsenosides markedly improved bile acid enterohepatic circulation via the FXR/CYP7A1 pathway, reducing hepatic and serum total bile acids and modulating bile acid pool composition by decreasing primary/unconjugated bile acids (CA, CDCA, and ß-MCA) and increasing conjugated bile acids (TCDCA, GCDCA, GDCA, and TUDCA), correlated with gut microbiota changes. In conclusion, our results suggest that ginsenoside Rb1, CK, and PPD supplementation offer promising prebiotic interventions for managing HFD-induced hyperlipidemia in rats, with ginsenoside Rb1 demonstrating superior efficacy.


Asunto(s)
Microbioma Gastrointestinal , Ginsenósidos , Hiperlipidemias , Sapogeninas , Ratas , Animales , Ginsenósidos/metabolismo , Dieta Alta en Grasa , Metabolismo de los Lípidos , Peso Corporal , Ácidos y Sales Biliares
3.
FASEB J ; 35(9): e21823, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34396581

RESUMEN

Exercise training exerts protective effects against diabetic nephropathy. This study aimed to investigate whether exercise training could attenuate diabetic renal injury via regulating endogenous hydrogen sulfide (H2 S) production. First, C57BL/6 mice were allocated into the control, diabetes, exercise, and diabetes + exercise groups. Diabetes was induced by intraperitoneal injection of streptozotocin (STZ). Treadmill exercise continued for four weeks. Second, mice was allocated into the control, diabetes, H2 S and diabetes + H2 S groups. H2 S donor sodium hydrosulfide (NaHS) was intraperitoneally injected once daily for four weeks. STZ-induced diabetic mice exhibited glomerular hypertrophy, tissue fibrosis and increased urine albumin levels, urine protein- and albumin-to-creatinine ratios, which were relieved by exercise training. Diabetic renal injury was associated with apoptotic cell death, as evidenced by the enhanced caspase-3 activity, the increased TdT-mediated dUTP nick-end labeling -positive cells and the reduced expression of anti-apoptotic proteins, all of which were attenuated by exercise training. Exercise training enhanced renal sirtuin 1 (SIRT1) expression in diabetic mice, accompanied by an inhibition of the p53-#ediated pro-apoptotic pathway. Furthermore, exercise training restored the STZ-mediated downregulation of cystathionine-ß-synthase (CBS) and cystathionine-γ-lyase (CSE) and the reduced renal H2 S production. NaHS treatment restored SIRT1 expression, inhibited the p53-mediated pro-apoptotic pathway and attenuated diabetes-associated apoptosis and renal injury. In high glucose-treated MPC5 podocytes, NaHS treatment inhibited the p53-mediated pro-apoptotic pathway and podocyte apoptosis in a SIRT1-dependent manner. Collectively, exercise training upregulated CBS/CSE expression and enhanced the endogenous H2 S production in renal tissues, thereby contributing to the modulation of the SIRT1/p53 apoptosis pathway and improvement of diabetic nephropathy.


Asunto(s)
Nefropatías Diabéticas/metabolismo , Sulfuro de Hidrógeno/metabolismo , Condicionamiento Físico Animal/fisiología , Sirtuina 1/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Animales , Apoptosis/fisiología , Caspasa 3/metabolismo , Línea Celular , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/fisiopatología , Nefropatías Diabéticas/fisiopatología , Riñón/metabolismo , Riñón/fisiopatología , Masculino , Ratones , Ratones Endogámicos C57BL , Podocitos/metabolismo , Transducción de Señal/fisiología
4.
Appl Microbiol Biotechnol ; 106(8): 3103-3112, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35389068

RESUMEN

Daptomycin is a new lipopeptide antibiotic for treatment of severe infection caused by multi-drug-resistant bacteria, but its production cost remains high currently. Thus, it is very important to improve the fermentation ability of the daptomycin producer Streptomyces roseosporus. Here, we found that the deletion of proteasome in S. roseosporus would result in the loss of ability to produce daptomycin. Therefore, transcriptome and 4D label-free proteome analyses of the proteasome mutant (Δprc) and wild type were carried out, showing 457 differential genes. Further, five genes were screened by integrated crotonylation omics analysis. Among them, two genes (orf04750/orf05959) could significantly promote the daptomycin synthesis by overexpression, and the fermentation yield in shake flask increased by 54% and 76.7%, respectively. By enhancing the crotonylation modification via lysine site mutation (K-Q), the daptomycin production in shake flask was finally increased by 98.8% and 206.3%, respectively. This result proved that the crotonylation modification of appropriate proteins could effectively modulate daptomycin biosynthesis. In summary, we established a novel strategy of gene screen for antibiotic biosynthesis process, which is more convenient than the previous screening method based on pathway-specific regulators. KEY POINTS: • Δprc strain has lost the ability of daptomycin production • Five genes were screened by multi-omics analysis • Two genes (orf04750/orf05959) could promote the daptomycin synthesis by overexpression.


Asunto(s)
Daptomicina , Streptomyces , Antibacterianos/farmacología , Complejo de la Endopetidasa Proteasomal , Proteoma/metabolismo , Streptomyces/metabolismo
5.
J Chem Phys ; 157(18): 184504, 2022 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-36379802

RESUMEN

Establishing the structure-property relationship is an important goal of glassy materials, but it is usually impeded by their disordered structure and non-equilibrium nature. Recent studies have illustrated that secondary (ß) relaxation is closely correlated with several properties in a range of glassy materials. However, it has been challenging to identify the pertinent structural features that govern it. In this work, we show that the so-called polyamorphous transition in metallic glasses offers an opportunity to distinguish the structural length scale of ß relaxation. We find that, while the glass transition temperature and medium-range orders (MROs) change rapidly across the polyamorphous transition, the intensity of ß relaxation and the short-range orders (SROs) evolve in a way similar to those in an ordinary reference glass without polyamorphous transition. Our findings suggest that the MRO accounts mainly for the global stiffening of the materials and the glass transition, while the SRO contributes more to ß relaxation per se.

6.
Curr Microbiol ; 79(12): 382, 2022 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-36329315

RESUMEN

BJC16-A38T, a Gram-negative, aerobic and non-motile rod-shaped strain was isolated from a permafrost wetland soil sample. BJC16-A38T was oxidase- and catalase-positive, and produced pale yellow colonies on modified R2A agar plates. The 16S rRNA gene sequence of BJC16-A38T shared the highest sequence similarity with those of Mucilaginibacter xinganensis BJC16-A31T (97.44%), Mucilaginibacter gotjawali SA3-7T (96.79%) and Mucilaginibacter frigoritolerans FT22T (96.14%). Phylogenetic analysis revealed that BJC16-A38T formed a separate lineage together with strain M. xinganensis BJC16-A31T in the genus Mucilaginibacter. BJC16-A38T contained menaquinone-7 (MK-7) as the predominant isoprenoid quinine. Major fatty acids in cells were iso-C15:0, summed feature 3 (16:1ω7c/16:1ω6c) and iso-C17:03-OH. BJC16-A38T contained phosphatidylethanolamine, two unknown polar lipids, six unidentified phospholipids and an unidentified aminolipid. The Genome of BJC16-A38T was sequenced using the Genome Analyzer IIx sequence platform and 38 contigs were produced in total with an average G + C percentage of 44.00%. The average nucleotide identity (ANI) of BJC16-A38T with respect to those of M. xinganensis BJC16-A31T, M. gotjawali SA3-7T and M. frigoritolerans FT22T were 79.60%, 77.24% and 77.58%, respectively. Digital DNA-DNA hybridization (DDH) values between BJC16-A38T and the tree reference strains were 21.30%, 19.60% and 19.70%, respectively. BJC16-A38T exhibited phenanthrene biodegradation activity that can degrade 88.02% phenanthrene in the MM medium after 7 days cultivation. Phenotypic, chemotaxonomic, phylogenetic and genomic characteristics concluded that strain BJC16-A38T represents a novel species of the genus Mucilaginibacter. Hence, the name Mucilaginibacter phenanthrenivorans sp. nov. is proposed. The type strain is BJC16-A38T (= CGMCC 1.12693T = NBRC 110383T).


Asunto(s)
Fenantrenos , Suelo , ARN Ribosómico 16S/genética , Filogenia , Humedales , Microbiología del Suelo , ADN Bacteriano/genética , Técnicas de Tipificación Bacteriana , Composición de Base , Análisis de Secuencia de ADN , Ácidos Grasos/metabolismo , Vitamina K 2
7.
Mar Drugs ; 20(2)2022 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-35200673

RESUMEN

In this review, we summarized the distribution of the chemically investigated Oceanapia sponges, including the isolation and biological activities of their secondary metabolites, covering the literature from the first report in 1989 to July 2019. There have been 110 compounds reported during this period, including 59 alkaloids, 33 lipids, 14 sterols and 4 miscellaneous compounds. Besides their unique structures, they exhibited promising bioactivities ranging from insecticidal to antibacterial. Their complex structural characteristics and diverse biological properties have attracted a great deal of attention from chemists and pharmaceuticals seeking to perform their applications in the treatment of disease.


Asunto(s)
Productos Biológicos/aislamiento & purificación , Poríferos/metabolismo , Alcaloides/química , Alcaloides/aislamiento & purificación , Alcaloides/farmacología , Animales , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Productos Biológicos/química , Productos Biológicos/farmacología , Humanos , Insecticidas/química , Insecticidas/aislamiento & purificación , Insecticidas/farmacología , Lípidos/química , Lípidos/aislamiento & purificación , Lípidos/farmacología , Metabolismo Secundario , Esteroles/aislamiento & purificación , Esteroles/farmacología
8.
World J Surg Oncol ; 20(1): 183, 2022 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-35668494

RESUMEN

BACKGROUND: Transforming growth factor (TGF)-ß signaling functions importantly in regulating tumor microenvironment (TME). This study developed a prognostic gene signature based on TGF-ß signaling-related genes for predicting clinical outcome of patients with lung adenocarcinoma (LUAD). METHODS: TGF-ß signaling-related genes came from The Molecular Signature Database (MSigDB). LUAD prognosis-related genes were screened from all the genes involved in TGF-ß signaling using least absolute shrinkage and selection operator (LASSO) Cox regression analysis and then used to establish a risk score model for LUAD. ESTIMATE and CIBERSORT analyzed infiltration of immune cells in TME. Immunotherapy response was analyzed by the TIDE algorithm. RESULTS: A LUAD prognostic 5-gene signature was developed based on 54 TGF-ß signaling-related genes. Prognosis of high-risk patients was significantly worse than low-risk patients. Both internal validation and external dataset validation confirmed a high precision of the risk model in predicting the clinical outcomes of LUAD patients. Multivariate Cox analysis demonstrated the model independence in OS prediction of LUAD. The risk model was significantly related to the infiltration of 9 kinds of immune cells, matrix, and immune components in TME. Low-risk patients tended to respond more actively to anti-PD-1 treatment, while high-risk patients were more sensitive to chemotherapy and targeted therapy. CONCLUSIONS: The 5-gene signature based on TGF-ß signaling-related genes showed potential for LUAD management.


Asunto(s)
Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/terapia , Biomarcadores de Tumor/metabolismo , Regulación Neoplásica de la Expresión Génica , Humanos , Inmunoterapia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , Pronóstico , Factor de Crecimiento Transformador beta/genética , Factor de Crecimiento Transformador beta/metabolismo , Microambiente Tumoral/genética
9.
Mar Drugs ; 20(9)2022 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-36135755

RESUMEN

Three unusual diterpenes with rare sarsolenane and capnosane skeletons, namely mililatensols A-C (1-3), were isolated from the South China Sea soft coral Sarcophyton mililatensis, leading to the first record of sarsolenane and capnosane diterpenes from the title animal. The structures of compounds 1-3 were established by extensive spectroscopic analysis and comparison with the literature data. Moreover, the absolute configuration of 2 was determined by TDDFT ECD calculations. In an in vitro bioassay, none of the isolated compounds showed obvious anti-inflammatory activity on LPS-induced TNF-α release in RAW264.7 macrophages. In the preliminary virtual screening of inhibitory potential against SARS-CoV-2 by molecular docking, the results showed these three diterpenes were potential SARS-CoV-2 Mpro inhibitors.


Asunto(s)
Antozoos , COVID-19 , Diterpenos , Animales , Antozoos/química , Antiinflamatorios/farmacología , Diterpenos/química , Lipopolisacáridos , Simulación del Acoplamiento Molecular , Estructura Molecular , SARS-CoV-2 , Factor de Necrosis Tumoral alfa
10.
Molecules ; 27(16)2022 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-36014541

RESUMEN

Ophiorrhiza japonica Bl. is a traditional Chinese materia medica widely used to treat several diseases. Chemical and pharmacological studies on O. japonica have been carried out; however, neither of them has been fully explored. In this study, an array of compounds was isolated from the title plant, including a new anthraquinone, ophiorrhizaquinone A (1), three alkaloids 2-4 and seven other compounds 5-11 with diverse structural types. Additionally, compounds 2, 5, 7, 8, 10 and 11 were isolated from the genus of Ophiorrhiza for the first time. Antioxidant bioassays in vitro using DPPH and ABTS were performed, and the results showed that compound 3 exhibited modest antioxidant activity with IC50 values of 0.0321 mg/mL and 0.0319 mg/mL, respectively. An in silico study of PPARα agonistic activities of compounds 2 and 3 was conducted by molecular docking experiments, revealing that both of them occupied the active site of PPARα via hydrogen bonds and hydrophobic interactions effectively. This study enriched both the phytochemical and pharmacological profiles of O. japonica.


Asunto(s)
Antioxidantes , Rubiaceae , Antioxidantes/química , Simulación del Acoplamiento Molecular , PPAR alfa , Fitoquímicos/farmacología , Extractos Vegetales/química , Rubiaceae/química
11.
Metab Eng ; 67: 198-215, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34166765

RESUMEN

Actinomycetes are recognized as excellent producers of microbial natural products, which have a wide range of applications, especially in medicine, agriculture and stockbreeding. The three main indexes of industrialization (titer, purity and stability) must be taken into overall consideration in the manufacturing process of natural products. Over the past decades, synthetic biology techniques have expedited the development of industrially competitive strains with excellent performances. Here, we summarize various rational engineering strategies for upgrading the performance of industrial actinomycetes, which include enhancing the yield of natural products, eliminating the by-products and improving the genetic stability of engineered strains. Furthermore, the current challenges and future perspectives for optimizing the industrial strains more systematically through combinatorial engineering strategies are also discussed.


Asunto(s)
Actinobacteria , Productos Biológicos , Actinobacteria/genética , Actinomyces , Ingeniería Metabólica , Biología Sintética
12.
Microb Cell Fact ; 19(1): 99, 2020 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-32375781

RESUMEN

BACKGROUND: Large-scale genome reduction has been performed to significantly improve the performance of microbial chassis. Identification of the essential or dispensable genes is pivotal for genome reduction to avoid synthetic lethality. Here, taking Streptomyces as an example, we developed a combinatorial strategy for systematic identification of large and dispensable genomic regions in Streptomyces based on multi-omics approaches. RESULTS: Phylogenetic tree analysis revealed that the model strains including S. coelicolor A3(2), S. albus J1074 and S. avermitilis MA-4680 were preferred reference for comparative analysis of candidate genomes. Multiple genome alignment suggested that the Streptomyces genomes embodied highly conserved core region and variable sub-telomeric regions, and may present symmetric or asymmetric structure. Pan-genome and functional genome analyses showed that most conserved genes responsible for the fundamental functions of cell viability were concentrated in the core region and the vast majority of abundant genes were dispersed in the sub-telomeric regions. These results suggested that large-scale deletion can be performed in sub-telomeric regions to greatly streamline the Streptomyces genomes for developing versatile chassis. CONCLUSIONS: The integrative approach of comparative genomics, functional genomics and pan-genomics can not only be applied to perform a multi-tiered dissection for Streptomyces genomes, but also work as a universal method for systematic analysis of removable regions in other microbial hosts in order to generate more miscellaneous and versatile chassis with minimized genome for drug discovery.


Asunto(s)
Genoma Bacteriano , Genómica/métodos , Streptomyces/genética , Proteínas Bacterianas/genética , Familia de Multigenes , Filogenia , Eliminación de Secuencia
13.
Microb Cell Fact ; 18(1): 16, 2019 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-30691531

RESUMEN

BACKGROUND: Streptomyces chattanoogensis L10 is the industrial producer of natamycin and has been proved a highly efficient host for diverse natural products. It has an enormous potential to be developed as a versatile cell factory for production of heterologous secondary metabolites. Here we developed a genome-reduced industrial Streptomyces chassis by rational 'design-build-test' pipeline. RESULTS: To identify candidate large non-essential genomic regions accurately and design large deletion rationally, we performed genome analyses of S. chattanoogensis L10 by multiple computational approaches, optimized Cre/loxP recombination system for high-efficient large deletion and constructed a series of universal suicide plasmids for rapid loxP or loxP mutant sites inserting into genome. Subsequently, two genome-streamlined mutants, designated S. chattanoogensis L320 and L321, were rationally constructed by depletion of 1.3 Mb and 0.7 Mb non-essential genomic regions, respectively. Furthermore, several biological performances like growth cycle, secondary metabolite profile, hyphae morphological engineering, intracellular energy (ATP) and reducing power (NADPH/NADP+) levels, transformation efficiency, genetic stability, productivity of heterologous proteins and secondary metabolite were systematically evaluated. Finally, our results revealed that L321 could serve as an efficient chassis for the production of polyketides. CONCLUSIONS: Here we developed the combined strategy of multiple computational approaches and site-specific recombination system to rationally construct genome-reduced Streptomyces hosts with high efficiency. Moreover, a genome-reduced industrial Streptomyces chassis S. chattanoogensis L321 was rationally constructed by the strategy, and the chassis exhibited several emergent and excellent performances for heterologous expression of secondary metabolite. The strategy could be widely applied in other Streptomyces to generate miscellaneous and versatile chassis with minimized genome. These chassis can not only serve as cell factories for high-efficient production of valuable polyketides, but also will provide great support for the upgrade of microbial pharmaceutical industry and drug discovery.


Asunto(s)
Ingeniería Genética , Genoma Bacteriano , Genómica , Streptomyces/genética , Proteínas Bacterianas/metabolismo , Productos Biológicos , Técnicas de Cultivo de Célula , Biología Computacional , Regulación Bacteriana de la Expresión Génica , Microbiología Industrial , Microorganismos Modificados Genéticamente , Familia de Multigenes , Natamicina/biosíntesis , Metabolismo Secundario
14.
J Org Chem ; 84(9): 5348-5356, 2019 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-30977647

RESUMEN

Lead was found to efficiently mediate the allylation reactions of carbonyl compounds with cyclic allylic halides in the presence of stoichiometric amounts of lithium chloride and a catalytic amount of GaCl3 (20 mol %), leading to the desired homoallylic alcohols in modest to high yields with excellent diastereocontrol (>99:1 syn/anti) and good functional group tolerance. In contrast, the use of either 2-pyridinecarboxaldehyde as the carbonyl substrate or ( E)-cinnamyl bromide as the allylating agent produced the corresponding product with reversed diastereoselectivity (>99:1 anti/syn).

15.
Appl Microbiol Biotechnol ; 103(18): 7583-7596, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31327020

RESUMEN

Fidaxomicin, an 18-membered macrolide antibiotic, is highly active against Clostridium difficile, the most common cause of diarrhea in hospitalized patients. Though the biosynthetic mechanism of fidaxomicin has been well studied, little is known about its regulatory mechanism. Here, we reported that FadR1, a LAL family transcriptional regulator in the fidaxomicin cluster of Actinoplanes deccanensis Yp-1, acts as an activator for fidaxomicin biosynthesis. The disruption of fadR1 abolished the ability to synthesize fidaxomicin, and production could be restored by reintegrating a single copy of fadR1. Overexpression of fadR1 resulted in an approximately 400 % improvement in fidaxomicin production. Electrophoretic mobility shift assays indicated that fidaxomicin biosynthesis is under the control of FadR1 through its binding to the promoter regions of fadM, fadA1-fadP2, fadS2-fadC, and fadE-fadF, respectively. And the conserved binding sites of FadR1 within the four promoter regions were determined by footprinting experiment. All results indicated that fadR1 encodes a pathway-specific positive regulator of fidaxomicin biosynthesis and upregulates the transcription levels of most of genes by binding to the four above intergenic regions. In summary, we not only clearly elucidate the regulatory mechanism of FadR1 but also provide strategies for the construction of industrial high-yield strain of fidaxomicin.


Asunto(s)
Actinoplanes/metabolismo , Antibacterianos/biosíntesis , Proteínas Bacterianas/metabolismo , Fidaxomicina/metabolismo , Proteínas Represoras/metabolismo , Actinoplanes/genética , Proteínas Bacterianas/genética , Vías Biosintéticas , Clostridioides difficile/efectos de los fármacos , Regulación Bacteriana de la Expresión Génica , Proteínas Represoras/genética
16.
Curr Microbiol ; 76(1): 95-99, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30421143

RESUMEN

Streptomyces are famed producers of secondary metabolites with diverse bioactivities and structures. However, biosynthesis of natural products will consume vast precursors from primary metabolism, and some secondary metabolites are toxic to the hosts. To overcome this circumstance and over-produce secondary metabolites, one of the strategies is to over-express biosynthetic genes under strong promoters specifically expressed during secondary metabolism. For this purpose, here based on Microarray and eGFP reporter assays, we obtained a promoter thlM4p, whose activity was undetectable in the first 2 days of fermentation, but sevenfold higher than the strong promoter ermE*p in the following days. Moreover, when the positive regulator gene scnRII was driven from thlM4p, natamycin yield increased 30% compared to ermE*p. Therefore, we provide a new way to identify promoters, which is silenced during primary metabolism while strongly expressed under secondary metabolism of Streptomyces.


Asunto(s)
Reactores Biológicos/microbiología , Natamicina/biosíntesis , Metabolismo Secundario/genética , Streptomyces/genética , Streptomyces/metabolismo , Fermentación/genética , Regulación Bacteriana de la Expresión Génica/genética , Metiltransferasas/genética , Familia de Multigenes/genética , Regiones Promotoras Genéticas/genética , Transcriptoma/genética
17.
Pak J Pharm Sci ; 31(6(Special)): 2869-2872, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30630801

RESUMEN

To investigate the efficaciousness of breast-conserving therapy in connection with neoadjuvant chemotherapy on breast cancer. 68 patients, who were confirmed going down with breast cancer and hospitalized from June 2015 and June 2017, were sampled and divided into two groups using the random digit table, i.e. the observation group (n=34) and the control group (n=34). Patients in the observation group experienced breast-conserving therapy integrated with neoadjuvant chemotherapy, but those in the control group received the radical resection of breast cancer. Patients' condition in surgery, incidence of post-surgery complications as well as patient survivals were compared and coded. In the observation group, surgical duration, intraoperative bleeding amount, length of stay in hospital and incidence rate of post-surgery complications were all lower than the patients with the similar conditions in the control group with evident distinctions in statistics (p<0.05). In the observation group, survival ratios of one-to-five-year living patients were evidently higher than those in the control group. The distinctions owned evident significance in calculations (p<0.05). In comparison of the recurrence ratio of disease and the rate of distant metastasis between the observation group (5.88% and 8.82%) and the control group (11.76% and 8.82%), differences had no statistical significance (p>0.05). Before treatment, compared with the score of life quality in the two groups, no evident distinction in statistical exists (p>0.05), however, after that, the life quality in the observation group evidently outweighs the quality in the control group, which shows the distinctions in statistics (p<0.05). Breast-conserving therapy in combination with neoadjuvant chemotherapy shows promising clinical value in ameliorating the life quality, decreasing the mortality rate and the incidence of adverse reaction, which is expected to be applied in clinical practices as a kind of safe and effective method.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/cirugía , Docetaxel/uso terapéutico , Epirrubicina/uso terapéutico , Mastectomía Segmentaria/métodos , Terapia Neoadyuvante/métodos , Adulto , Anciano , Neoplasias de la Mama/secundario , China/epidemiología , Femenino , Humanos , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Calidad de Vida , Recurrencia , Análisis de Supervivencia , Resultado del Tratamiento
18.
Ecotoxicol Environ Saf ; 141: 98-106, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28319865

RESUMEN

The concentrations of 16 priority polycyclic aromatic hydrocarbons (PAHs) were measured in 128 surface soil samples from Xiangfen County, northern China. The total mass concentration of these PAHs ranged from 52 to 10,524ng/g, with a mean of 723ng/g. Four-ring PAHs contributed almost 50% of the total PAH burden. A self-organizing map and positive matrix factorization were applied to investigate the spatial distribution and source apportionment of PAHs. Three emission sources of PAHs were identified, namely, coking ovens (21.9%), coal/biomass combustion (60.1%), and anthracene oil (18.0%). High concentrations of low-molecular-weight PAHs were particularly apparent in the coking plant zone in the region around Gucheng Town. High-molecular-weight PAHs mainly originated from coal/biomass combustion around Gucheng Town, Xincheng Town, and Taosi Town. PAHs in the soil of Xiangfen County are unlikely to pose a significant cancer risk for the population.


Asunto(s)
Monitoreo del Ambiente/métodos , Hidrocarburos Policíclicos Aromáticos/análisis , Contaminantes del Suelo/análisis , Suelo/química , Adulto , Antracenos/análisis , Niño , China , Carbón Mineral/análisis , Humanos , Neoplasias/inducido químicamente , Hidrocarburos Policíclicos Aromáticos/toxicidad , Medición de Riesgo , Contaminantes del Suelo/toxicidad
19.
J Tradit Chin Med ; 36(1): 45-50, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26946618

RESUMEN

OBJECTIVE: To assess the efficacy and safety of Yunxiangjing (YXJ), derived from Chinese herbal medicine, in the management of acute radiation-induced proctitis (ARIP) in patients with pelvic malignancy. METHODS: Forty-eight patients with grade 2 ARIP were administered YXJ as an enema (1 : 30 dilution) for 2 weeks and followed up for 2 years. All were assessed for response and ARIP grade. Quality of life (QOL) was assessed with the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30. RESULTS: Of the 48 patients, six (12.5%) achieved complete remission of ARIP and 28 (58.3%) showed a decrease from grade 2 to grade 1 ARIP. No patient experienced a grade ≥3 toxicity. At the end of radiotherapy, patients showed significant improvements in QOL (P < 0.05). Two years after treatment, 46 patients showed no late toxicity, with only two experiencing grade 1 late toxicity. CONCLUSION: YXJ can be used as an enema to manage acute radiation-induced proctitis in cancer patients undergoing radiotherapy. These findings suggest that YXJ enema may be an alternative treatment of ARIP.


Asunto(s)
Medicamentos Herbarios Chinos/administración & dosificación , Neoplasias Pélvicas/radioterapia , Proctitis/tratamiento farmacológico , Radioterapia/efectos adversos , Adulto , Medicamentos Herbarios Chinos/efectos adversos , Enema , Femenino , Humanos , Persona de Mediana Edad , Proctitis/etiología
20.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 38(5): 497-506, 2016 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-27825404

RESUMEN

Objective To compare the effecacy of human mesenchymal stromal cell (hMSC) with human mononuclear cell (hMNC) in treating rat cerebral infarct.Methods The SD rat models of cerebral infarct were established by distal middle cerebral artery occlusion (dMCAO). Rats were divided into four groups: sham,ischemia vehicle,MSC,and MNC transplantation groups. For the transplantation group,1×106 hMSCs or hMNCs were intravascularly transplanted into the tail vein 1 hour after the ischemia onset. The ischemia vehicle group received dMCAO surgery and intravascular saline injection 1,3,5,and 7 days after the ischemia onset,and then behavioral tests were performed. At 48 h after the ischemia onset,the abundance of Iba- 1,the symbol of activated microglia,was evaluated in the peri-ischemia striatum area; meanwhile,the neurotrophic factors such as glial cell line-derived neurotrophic factor (GDNF) and brain-derived neurotrophic factor (BDNF) in ipsilateral peri-ischemia striatum area were also measured. Results The relative infarct volume in ischemia vehicle group,hMSC group,and hMNC transplantation group were (37.85±4.40)%,(33.41±3.82)%,and (30.23±3.63)%,respectively. The infarct volumes of MSC group (t=2.100,P=0.034) and MNC group (t=2.109,P=0.0009) were significantly smaller than that of ischemia vehicle group,and that of MNC group was significantly smaller than that of MSC group (t=1.743,P=0.043). One day after transplantation,the score of ischemia vehicle group in limb placing test was (4.32±0.71)%,which was significantly lower than that in sham group (9.73±0.36)% (t=2.178,P=8.61×10-11). The scores of MSC and MNC group,which were (5.09±0.62)% (t=2.1009,P=0.024) and (5.90±0.68)% (t=2.1008,P=0.0001),respectively,were significantly higher than that of ischemia vehicle group; also,the score of MNC group was significantly higher than that of MSC group(t=2.1009,P=0.0165). The contralateral forelimb scores of MSC and MNC groups in beam walking test were (5.56±0.86)% (t=2.120,P=0.020) and (5.13±0.95)% (t=2.131,P=0.003),were both significantly lower than that of ischemia vehicle group [(6.47±0.61)%]. Three days after the transplantation,the limb placing test score of MNC group [(6.91±1.10)%] was significantly higher than that of ischemia vehicle group (5.80±0.82)% (t=2.110,P=0.027). The score of MSC group [(6.30±0.77)%] showed no statistic difference with that of ischemia vehicle group(t=2.101,P=0.199).The contralateral forelimb scores of MNC group in beam walking test [(4.34±0.58)%] was significantly lower than that of ischemia vehicle group [(5.31±0.65)%] (t=2.100,P=0.006) and MSC group [(4.92±0.53)%] (t=2.100,P=0.041); there was no statistic difference between MSC group and ischemia vehicle group (t=2.109,P=0.139). The relative abundance of Iba- 1 in sham,ischemia vehicle,MSC,and MNC groups was 1.00+0.00,1.72±0.21,1.23±0.08,and 1.48±0.06,respectively. The Iba-1 relative abundance of ischemia vehicle group was significantly higher than that of sham group (t=2.262,P=2.9×10-6). The Iba-1 relative abundances of both MSC (t=2.178,P=3.91×10-5)and MNC (t=2.200,P=0.007)groups were significantly lower than that of ischemia vehicle group. It was also significantly lower in MNC group than in MSC group also (t=2.120,P=7.09×10-6). Three days after transplantation,the BDNF and GDNF levels of MSC group,which were (531.127±73.176)pg/mg (t=2.109,P=0.003)and(127.780±16.733)pg/mg(t=2.100,P=2.76×10-5),respectively,were significantly higher than those of ischemia vehicle group,which were (401.988±89.006)pg/mg and (86.278±14.832) pg/mg,respectively. The BDNF and GDNF levels of MNC group,which were (627.429±65.646)pg/mg (t=2.144,P=0.017) and (153.117±20.443)pg/mg (t=2.109,P=0.010),respectively,were all significantly higher than that of MSC group. At day 7,the BDNF and GDNF levels of MSC group,which were (504.776±83.282)pg/mg (t=2.101,P=0.005) and (81.641±11.019)pg/mg (t=2.100,P=0.002),respectively,were significantly higher than those of ischemia vehicle group,which were (389.257±70.440)pg/mg and (64.322±9.855) pg/mg,respectively. The BDNF and GDNF levels of MNC group,which were (589.068±63.323)pg/mg (t=2.100,P=0.027) and (102.161±19.932)pg/mg (t=2.144,P=0.017),respectively,were all significantly higher than that of MSC group. Conclusions Both hMSC and hMNC are beneficial to the ischemia-damaged brain when they are intravascularly transplanted within 1 h after the onset of ischemia. The anti-inflammation ability and secretion of neurotrophic factors are the underlying mechanisms of the therapeutic effects. MNC is more effective than MSC in reducing infarct area and improving behaviors,which might be explained by the fact that MNC induces more GDNF and BDNF in brain than MSC.


Asunto(s)
Isquemia Encefálica/terapia , Infarto de la Arteria Cerebral Media/terapia , Leucocitos Mononucleares/citología , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/citología , Animales , Médula Ósea , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Modelos Animales de Enfermedad , Feto , Factor Neurotrófico Derivado de la Línea Celular Glial/metabolismo , Humanos , Masculino , Ratas , Ratas Sprague-Dawley
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