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1.
Front Mol Neurosci ; 17: 1400927, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38756705

RESUMEN

Valeriana jatamansi Jones (VJJ), renowned for its extensive history in traditional Chinese medicine and ethnomedicine within China, is prevalently utilized to alleviate ailments such as epigastric distension and pain, gastrointestinal disturbances including food accumulation, diarrhea, and dysentery, as well as insomnia and other diseases. Moreover, the Iridoid-rich fraction derived from Valeriana jatamansi Jones (IRFV) has demonstrated efficacy in facilitating the recuperation of motor functions after spinal cord injury (SCI). This study is aimed to investigate the therapeutic effect of IRFV on SCI and its underlying mechanism. Initially, a rat model of SCI was developed to assess the impact of IRFV on axonal regeneration. Subsequently, employing the PC12 cell model of oxidative damage, the role and mechanism of IRFV in enhancing axonal regeneration were explored using the phosphoinositide-3-kinase (PI3K)/protein kinase B (Akt) signaling pathway inhibitor LY294002. Ultimately, the same inhibitor was administered to SCI rats to confirm the molecular mechanism through which IRFV promotes axonal regeneration by activating the PI3K/Akt signaling pathway. The results showed that IRFV significantly enhanced motor function recovery, reduced pathological injury, and facilitated axonal regeneration in SCI rats. In vitro experiments revealed that IRFV improved PC12 cell viability, augmented axonal regeneration, and activated the PI3K/Akt signaling pathway. Notably, the inhibition of this pathway negated the therapeutic benefits of IRFV in SCI rats. In conclusion, IRFV promote promotes axonal regeneration and recovery of motor function after SCI through activation of the PI3K/Akt signaling pathway.

3.
J Leukoc Biol ; 115(6): 1042-1052, 2024 05 29.
Artículo en Inglés | MEDLINE | ID: mdl-38315633

RESUMEN

One of the difficulties in the treatment of hepatocellular carcinoma is that it is impossible to eliminate the inhibitory effect of the tumor microenvironment on immune response. Therefore, it is particularly important to understand the formation process of the tumor microenvironment. Chronic inflammation is the core factor of cancer occurrence and the leading stage of inflammation-cancer transformation, and the natural killer cell subsets play an important role in it. Our study confirmed that in the stage of chronic liver injury, the local immunosuppressive microenvironment of the liver (i.e. the damaged microenvironment) has been formed, but this inhibitory effect is only for peripheral natural killer cells and has no effect on tissue-resident natural killer subsets. The markers of damage microenvironment are the same as those of tumor microenvironment.


Asunto(s)
Inflamación , Células Asesinas Naturales , Células Asesinas Naturales/inmunología , Animales , Inflamación/inmunología , Inflamación/patología , Hígado/patología , Hígado/inmunología , Masculino , Humanos , Microambiente Tumoral/inmunología , Enfermedad Crónica
5.
Medicine (Baltimore) ; 102(50): e36434, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-38115366

RESUMEN

Spinal cord injury (SCI) is characterized by high rates of disability and death. Valeriana jatamansi Jones (VJJ), a Chinese herbal medicine, has been identified to improve motor function recovery in rats with SCI. The study aimed to analyze the potential molecular mechanisms of action of VJJ in the treatment of SCI. The main ingredients of VJJ were obtained from the literature and the SwissADME platform was used to screen the active ingredients. The Swiss TargetPrediction platform was used to predict the targets of VJJ, and the targets of SCI were obtained from the GeneCards and OMIM databases. The intersecting genes were considered potential targets of VJJ in SCI. The protein-protein interaction network was constructed using the STRING database and the hub genes of VJJ for SCI treatment were screened according to their degree values. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes enrichment analyses were performed using the Metascape database. Cytoscape software was used to construct the "herb-ingredient-target-pathway" network. Preliminary validation was performed using molecular docking via Auto Dock Vina software. A total of 56 active ingredients of VJJ, mainly iridoids, were identified. There were 1493 GO items (P < .01) and 173 signaling pathways (P < .01) obtained from GO and Kyoto Encyclopedia of Genes and Genomes enrichment, including the phosphoinositide-3-kinase (PI3K)-protein kinase B (Akt) signaling pathway, hypoxia-inducible factor 1 signaling pathway, and tumor necrosis factor signaling pathway. Molecular docking revealed that 12 hub genes enriched in the PI3K/Akt signaling pathway had a high binding affinity for the active ingredient of VJJ. VJJ may exert its therapeutic effects on SCI through the iridoid fraction, acting on signal transducer and activator of transcription 3, CASP3, AKT1, tumor necrosis factor, mammalian target of rapamycin, interleukin 6, and other hub genes, which may be related to the PI3K/Akt signaling pathway.


Asunto(s)
Medicamentos Herbarios Chinos , Valeriana , Animales , Ratas , Simulación del Acoplamiento Molecular , Proteínas Proto-Oncogénicas c-akt , Farmacología en Red , Fosfatidilinositol 3-Quinasas , Factor de Necrosis Tumoral alfa , Iridoides , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico , Mamíferos
6.
J Org Chem ; 88(21): 15507-15515, 2023 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-37862576

RESUMEN

The CF3 group attached to N-aryl hydrazone could be activated upon treatment with a suitable base, thus serving as an excellent C1 unit for the assembly of a series of 1,3,4-oxadiazoles by reaction with hydrazides. The transformation is proposed to proceed via the intermediate formation of a gem-difluorinated azoalkene. Furthermore, this reaction features simple conditions and a broad substrate scope with respect to both trifluoromethyl N-aryl hydrazones and hydrazides.

7.
Spectrochim Acta A Mol Biomol Spectrosc ; 285: 121872, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36152504

RESUMEN

Small molecular food contaminants, such as mycotoxins, pesticide residues and antibiotics, are highly probable to be passively introduced in food at all stages of its processing, including planting, harvest, production, transportation and storage. Owing to the high risks caused by the unknowing intake and accumulation in human, there is an urgent need to develop rapid, sensitive and efficient methods to monitor them. Fluorescence-based aptasensors provide a promising platform for this area owing to its simple operation, high sensitivity, wide application range and economical practicability. In this paper, the common sorts of small molecular contaminants in foods, namely mycotoxins, pesticides, antibiotics, etc, are briefly introduced. Then, we make a comprehensive review, from fluorescence resonance energy transfer (in turn-on, turn-off, and ratiometric mode, as well as energy upconversion) to fluorescence polarization, of the fluorescence-based aptasensors for the determination of these food contaminants reported in the last five years. The principle of signal generation, the advances of each sort of fluorescent aptasensors, as well as their applications are introduced in detail. Additionally, we also discussed the challenges and perspectives of the fluorescent aptasensors for small molecular food contaminants. This work will offer systematic overview and inspiration for amateurs, researchers and developers of fluorescence-based aptasensors for the detection of small molecules.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Micotoxinas , Humanos , Aptámeros de Nucleótidos/química , Técnicas Biosensibles/métodos , Transferencia Resonante de Energía de Fluorescencia , Antibacterianos
8.
J Leukoc Biol ; 112(6): 1649-1661, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36073777

RESUMEN

Due to the ability of γδ T cells to bridge adaptive and innate immunity, γδ T cells can respond to a variety of molecular cues and acquire the ability to induce a variety of cytokines such as IL-17 family, IFN-γ, IL-4, and IL-10. IL-17+ γδ T cells (γδ T17 cells) populations have recently received considerable interest as they are the major early source of IL-17A in many immune response models. However, the exact mechanism of γδ T17 cells is still poorly understood, especially in the context of cardiovascular disease (CVD). CVD is the leading cause of death in the world, and it tends to be younger. Here, we offer a review of the cardiovascular inflammatory and immune functions of γδ T17 cells in order to understand their role in CVD, which may be the key to developing new clinical applications.


Asunto(s)
Enfermedades Cardiovasculares , Células Th17 , Humanos , Enfermedades Cardiovasculares/inmunología , Inmunidad Innata , Interleucina-17 , Receptores de Antígenos de Linfocitos T gamma-delta , Subgrupos de Linfocitos T , Células Th17/inmunología
9.
Rapid Commun Mass Spectrom ; 36(20): e9363, 2022 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-35902380

RESUMEN

RATIONALE: Many methods have been reported for the production of rare ginsenosides, including heat treatment, acid hydrolysis, alkaline hydrolysis, enzymatic hydrolysis, and microbial transformation. However, the conversion of original ginsenosides to rare ginsenosides under the dual conditions of citric acid and high-pressure steam sterilization has rarely been reported. METHODS: In this study, a method involving ultrahigh-performance liquid chromatography coupled to ion mobility quadrupole time-of-flight mass spectrometry was developed for analysis of chemical transformation of protopanaxatriol (PPT)-type ginsenosides Rg1 and Re, protopanaxadiol (PPD)-type ginsenoside Rb1 , and total ginsenosides in the dual conditions of citric acid and high-pressure steam sterilization. An internal ginsenoside database containing 126 known ginsenosides and 18 ginsenoside reference compounds was established to identify the transformation products and explore possible transformation pathways and mechanisms. RESULTS: A total of 54 ginsenosides have been preliminarily identified in the transformation products of PPD-type ginsenosides Rg1 and Re, PPD-type ginsenoside Rb1 , and total ginsenosides, and the possible transformation pathways were as follows: Rg1 , Re → 20(S)-Rh12 , 20(R)-Rh12 ; Rg1 , Re → 20(S)-Rh1 , 20(R)-Rh1 → Rk3 , Rh4 , Rh5 ; Rb1 → gypenoside LXXV; Rb1 → 20(S)-Rg3 , 20(R)-Rg3 → Rk1 , Rg5 ; Re → 20(S)-Rg2 , 20(R)-Rg2 → 20(S)-Rf2 , 20(R)-Rf2 , Rg4 , F4 . CONCLUSIONS: The results elucidated the possible transformation pathways and mechanisms of ginsenosides in the dual conditions of citric acid and high-pressure steam sterilization, which were helpful for revealing the mechanisms of ginsenosides and enhanced safety and quality control of pharmaceuticals and nutraceuticals. Meanwhile, a simple, efficient, and practical method was developed for the production of rare ginsenosides, which has the potential to produce diverse rare ginsenosides on an industrial scale.


Asunto(s)
Ginsenósidos , Panax , Cromatografía Liquida , Ácido Cítrico , Ginsenósidos/química , Espectrometría de Masas , Panax/química , Saponinas , Vapor/análisis , Triterpenos
10.
Microb Cell Fact ; 21(1): 76, 2022 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-35525939

RESUMEN

BACKGROUND: Ergothioneine (ERG) is a potent histidine-derived antioxidant that confers health-promoting effects. Only certain bacteria and fungi can biosynthesize ERG, but the ERG productivity in natural producers is low. ERG overproduction through genetic engineering represents an efficient and cost-effective manufacturing strategy. RESULTS: Here, we showed that Trichoderma reesei can synthesize ERG during conidiogenesis and hyphal growth. Co-expression of two ERG biosynthesis genes (tregt1 and tregt2) from T. reesei enabled E. coli to generate 70.59 mg/L ERG at the shaking flask level after 48 h of whole-cell biocatalysis, whereas minor amounts of ERG were synthesized by the recombinant E. coli strain bearing only the tregt1 gene. By fed-batch fermentation, the extracellular ERG production reached 4.34 g/L after 143 h of cultivation in a 2-L jar fermenter, which is the highest level of ERG production reported thus far. Similarly, ERG synthesis also occurred in the E. coli strain engineered with the two well-characterized genes from N. crassa and the ERG productivity was up to 4.22 g/L after 143 h of cultivation under the above-mentioned conditions. CONCLUSIONS: Our results showed that the overproduction of ERG in E. coli could be achieved through two-enzymatic steps, demonstrating high efficiency of the fungal ERG biosynthetic pathway. Meanwhile, this work offers a more promising approach for the industrial production of ERG.


Asunto(s)
Ergotioneína , Vías Biosintéticas , Escherichia coli/genética , Escherichia coli/metabolismo , Fermentación , Histidina/genética , Ingeniería Metabólica
11.
Nat Prod Res ; 36(13): 3297-3302, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33930984

RESUMEN

Two new chroman-4-ones penicichromanone A (1) and penicichromanone B (2), together with three known compounds conioxepinol C (3), emodin (4) and moniliphenone (5), were obtained from the endophytic fungus Penicillium chrysogenum, which was isolated from the bark of Eucommia ulmoides Oliver. The structures of 1 and 2 were elucidated by detailed analysis of HRESIMS, 1D/2D NMR and ECD spectra. All the compounds were evaluated for their anti-inflammatory activities using HEK293 cells, and compounds 1, 3, 4 and 5 exhibited significant inhibitory effects on TNF-α-stimulated NF-κB activation.


Asunto(s)
Eucommiaceae , Penicillium chrysogenum , Penicillium , Antiinflamatorios/farmacología , Cromanos , Eucommiaceae/química , Células HEK293 , Humanos , Penicillium chrysogenum/química
12.
J Pharm Biomed Anal ; 206: 114385, 2021 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-34597841

RESUMEN

Kai-Xin-San (KXS) is a traditional Chinese medicine (TCM) formula containing four herbal medicines: Ginseng Radix Rhizoma, Polygalae Radix, Poria and Acori Tatarinowii Rhizoma. A large number of pharmacological studies in vitro and in vivo have shown that KXS is characterized by anti-depression, anti-Alzheimer's disease, anti-oxidation and other activities. However, the pharmacodynamic substance basis studies of KXS are hitherto quite limited. Here, KXS was identified and determined by ultra-performance liquid chromatography-quadrupole-Orbitrap mass spectrometry (UPLC-Q-Orbitrap MS) and gas chromatography-mass spectrometry (GC-MS). Firstly, the data-dependent acquisition mode (DDA) of UPLC-Q-Orbitrap MS combined with the inclusion list were used to collected the chemical composition. The chemical constituents of KXS were identified by local database on compound discoverer™ 3.1 software and Xcalibur 4.1 software. With the use of this approach, a total of 211 compounds were identified from KXS. Wherein 60 compounds were from Ginseng Radix Rhizoma, 40 compounds were from Poria, and 111 compounds were from Polygala Radix, respectively. Secondly, 105 volatile constituents were identified by GC-MS analysis, which were mainly derived from Acori Tatarinowii Rhizoma. Besides, an adjusted parallel reaction monitoring method was established and validated to quantify the seventeen major compounds in different herbal medicines of KXS, which were chosen as the benchmarked substances to evaluate the quality of KXS. In conclusion, this study provided a generally applicable strategy for global metabolite identification of the complicated components and determination of multi-component content in traditional Chinese medicines.


Asunto(s)
Medicamentos Herbarios Chinos , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , Cromatografía de Gases y Espectrometría de Masas , Espectrometría de Masas
13.
Artículo en Inglés | MEDLINE | ID: mdl-34457017

RESUMEN

Betel nut, the fruit of Areca catechu L, has a long medical history in Southeast Asia. It is native to Malaysia and is cultivated and processed extensively in subtropical regions, such as South China and India. Betel nut almost appears as a "snack" in various occasions in most parts of China. Clinically, betel nut can play a certain pharmacology role and was used in malaria, ascariasis, arthritis, enterozoic abdominalgia, stagnation of food, diarrhea, edema, and beriberi. The nervous excitement of betel nut chewing has made it gradually become popular. However, chewing betel nut can induce oral submucosal fibrosis (OSF) and oral cancer (OC). At the same time, long-term chewing of betel nut also causes inhaled asthma, sperm reducing, betel quid dependence (BQD), and uterine and esophageal cancers. The main components of processed betel nut are the goal of this review. This study will mainly start from the pharmacological activity and toxicology study of betel nut in recent years, aiming to seek its advantages and disadvantages. In the meantime, this study will analyze and emphasize that betel nut and arecoline are the high-risk factors for oral cancer, which should arouse attention and vigilance of the public.

14.
Microb Cell Fact ; 20(1): 170, 2021 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-34454478

RESUMEN

BACKGROUND: Melatonin has attracted substantial attention because of its excellent prospects for both medical applications and crop improvement. The microbial production of melatonin is a safer and more promising alternative to chemical synthesis approaches. Researchers have failed to produce high yields of melatonin in common heterologous hosts due to either the insolubility or low enzyme activity of proteins encoded by gene clusters related to melatonin biosynthesis. RESULTS: Here, a combinatorial gene pathway for melatonin production was successfully established in Escherichia coli by combining the physostigmine biosynthetic genes from Streptomyces albulus and gene encoding phenylalanine 4-hydroxylase (P4H) from Xanthomonas campestris and caffeic acid 3-O-methyltransferase (COMT) from Oryza sativa. A threefold improvement of melatonin production was achieved by balancing the expression of heterologous proteins and adding 3% glycerol. Further protein engineering and metabolic engineering were conducted to improve the conversion of N-acetylserotonin (NAS) to melatonin. Construction of COMT variant containing C303F and V321T mutations increased the production of melatonin by fivefold. Moreover, the deletion of speD gene increased the supply of S-adenosylmethionine (SAM), an indispensable cofactor of COMT, which doubled the yield of melatonin. In the final engineered strain EcMEL8, the production of NAS and melatonin reached 879.38 ± 71.42 mg/L and 136.17 ± 1.33 mg/L in a shake flask. Finally, in a 2-L bioreactor, EcMEL8 produced 1.06 ± 0.07 g/L NAS and 0.65 ± 0.11 g/L melatonin with tryptophan supplementation. CONCLUSIONS: This study established a novel combinatorial pathway for melatonin biosynthesis in E. coli and provided alternative strategies for improvement of melatonin production.


Asunto(s)
Escherichia coli/metabolismo , Melatonina/biosíntesis , Ingeniería Metabólica/métodos , Ingeniería de Proteínas/métodos , Escherichia coli/genética
15.
Enzyme Microb Technol ; 142: 109680, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33220868

RESUMEN

The microbial transglutaminase (mTGase) from Streptomyces mobaraense is widely used in the food industry. However, recombinant production of mTGase is challenging because the mTGase is synthesized as an inactive zymogen, and needs to be activated by proteolytic processing. In this study, self-cleaving intein Ssp DnaB was applied to activate the mTGase in Corynebacterium glutamicum. Premature cleavage of intein Ssp DnaB also occurred, but instead of suppressing premature cleavage, this phenomenon was used to produce active mTGase in C. glutamicum. Both SDS-PAGE analysis and mTGase activity assays indicated that the premature cleavage of intein Ssp DnaB activated the mTGase intracellularly in C. glutamicum. The subsequent N-terminal amino acid sequencing and site-directed mutagenesis studies further showed that the premature cleavage activated the mTGase intracellularly, in a highly specific manner. Moreover, the growth performance of C. glutamicum was not noticeably affected by the intracellular expression of active mTGase. Finally, the mTGase was produced in a 2 L bioreactor, with activity up to 49 U/mL, the highest intracellular mTGase activity ever reported. Using premature cleavage of intein Ssp DnaB to activate mTGase in C. glutamicum, we produced high levels of intracellular active mTGase. Moreover, this approach did not require any further processing steps, such as protease treatment or lengthy incubation, greatly simplifying the production of active mTGase. This efficient and simple approach has great potential for the large-scale industrial production of active mTGase.


Asunto(s)
Corynebacterium glutamicum , Streptomyces , Corynebacterium glutamicum/metabolismo , Inteínas , Empalme de Proteína , Streptomyces/metabolismo , Transglutaminasas/genética
16.
Molecules ; 24(18)2019 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-31500338

RESUMEN

Fritillariae Bulbus is a precious Chinese herbal medicine that is grown at high elevation and used to relieve coughs, remove phlegm, and nourish the lungs. Historically, Fritillariae Bulbus has been divided into two odourless crude drugs: Fritillariae Cirrhosae Bulbus and Fritillariae Thunbergii Bulbus. However, now the Chinese Pharmacopoeia has described five Fritillariae Bulbus-the new additions include Fritillariae Pallidiflorae Bulbus, Fritillariae Ussuriensis Bulbus, and Fritillariae Hupehensis Bulbus. Because the morphology of dried Fritillariae Bulbus is similar, it is difficult to accurately identify the different types of Fritillariae Bulbus. In the current study, we develop a method combining DNA barcoding and high-performance liquid chromatography (HPLC) to help distinguish Fritillariae Cirrhosae Bulbus from other Fritillariae Bulbus and guarantee species traceability of the five types of Fritillariae Bulbus. We report on the validation of an integrated analysis method for plant species identification using DNA barcoding that is based on genetic distance, identification efficiency, inter- and intra-specific variation, calculated nearest distance, neighbour-joining tree and barcoding gap. Our results show that the DNA barcoding data successfully identified the five Fritillariae Bulbus by internal transcribed spacer region (ITS) and ITS2, with the ability to distinguish the species origin of these Fritillariae Bulbus. ITS2 can serve as a potentially useful DNA barcode for the Fritillaria species. Additionally, the effective chemical constituents are identified by HPLC combined with a chemical identification method to classify Fritillaria. The HPLC fingerprint data and HCA (hierarchical clustering analysis) show that Fritillariae Cirrhosae Bulbus is clearly different from Fritillariae Thunbergii Bulbus and Fritillariae Hupehensis Bulbus, but there is no difference between Fritillariae Cirrhosae Bulbus, Fritillariae Ussuriensis Bulbus, and Fritillariae Pallidiflorae Bulbus. These results show that DNA barcoding and HPLC fingerprinting can discriminate between the five Fritillariae Bulbus types and trace species to identify related species that are genetically similar.


Asunto(s)
Código de Barras del ADN Taxonómico/métodos , Medicamentos Herbarios Chinos/química , Fritillaria/clasificación , Cromatografía Líquida de Alta Presión , Análisis por Conglomerados , ADN Mitocondrial/genética , ADN de Plantas/genética , Fritillaria/química , Fritillaria/genética , Filogenia , Análisis de Secuencia de ADN
17.
J Asian Nat Prod Res ; 19(10): 981-986, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28276764

RESUMEN

Two new malic acid derivatives, namely eucomic acid 1-methyl ester (2) and 6'''-acetylmilitaline (7), together with ten known compounds (1, 3-6, 8-12), were isolated from the dry tubers of Bletilla striata (Thunb.) Reichb. F., a perennial traditional Chinese medicinal herb, which was used for the treatment of pneumonophthisis, pneumonorrhagia, tuberculosis, and hemorrhage of the stomach or lung. Their structures were elucidated by spectroscopic analyses, including 1D-, 2D-NMR, and HR-ESI-MS.


Asunto(s)
Medicamentos Herbarios Chinos/aislamiento & purificación , Malatos/aislamiento & purificación , Orchidaceae/química , Fenoles/aislamiento & purificación , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Malatos/química , Malatos/farmacología , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Fenoles/química , Fenoles/farmacología , Tubérculos de la Planta/química
18.
J Bacteriol ; 199(1)2017 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-27795315

RESUMEN

Ectoine has osmoprotective effects on Sinorhizobium meliloti that differ from its effects in other bacteria. Ectoine does not accumulate in S. meliloti cells; instead, it is degraded. The products of the ehuABCD-eutABCDE operon were previously discovered to be responsible for the uptake and catabolism of ectoine in S. meliloti However, the mechanism by which ectoine is involved in the regulation of the ehuABCD-eutABCDE operon remains unclear. The ehuR gene, which is upstream of and oriented in the same direction as the ehuABCD-eutABCDE operon, encodes a member of the MocR/GntR family of transcriptional regulators. Quantitative reverse transcription-PCR and promoter-lacZ reporter fusion experiments revealed that EhuR represses transcription of the ehuABCD-eutABCDE operon, but this repression is inhibited in the presence of ectoine. Electrophoretic mobility shift assays and DNase I footprinting assays revealed that EhuR bound specifically to the DNA regions overlapping the -35 region of the ehuA promoter and the +1 region of the ehuR promoter. Surface plasmon resonance assays further demonstrated direct interactions between EhuR and the two promoters, although EhuR was found to have higher affinity for the ehuA promoter than for the ehuR promoter. In vitro, DNA binding by EhuR could be directly inhibited by a degradation product of ectoine. Our work demonstrates that EhuR is an important negative transcriptional regulator involved in the regulation of ectoine uptake and catabolism and is likely regulated by one or more end products of ectoine catabolism. IMPORTANCE: Sinorhizobium meliloti is an important soil bacterium that displays symbiotic interactions with legume hosts. Ectoine serves as a key osmoprotectant for S. meliloti However, ectoine does not accumulate in the cells; rather, it is degraded. In this study, we characterized the transcriptional regulation of the operon responsible for ectoine uptake and catabolism in S. meliloti We identified and characterized the transcription repressor EhuR, which is the first MocR/GntR family member found to be involved in the regulation of compatible solute uptake and catabolism. More importantly, we demonstrated for the first time that an ectoine catabolic end product could modulate EhuR DNA-binding activity. Therefore, this work provides new insights into the unique mechanism of ectoine-induced osmoprotection in S. meliloti.


Asunto(s)
Aminoácidos Diaminos/metabolismo , Proteínas Bacterianas/metabolismo , Regulación Bacteriana de la Expresión Génica/fisiología , Sinorhizobium meliloti/metabolismo , Secuencia de Aminoácidos , Proteínas Bacterianas/genética , Secuencia de Bases , ADN Bacteriano/genética , Eliminación de Gen , Osmorregulación , Regiones Promotoras Genéticas , Unión Proteica , ARN Bacteriano/genética , ARN Bacteriano/metabolismo
19.
Asian J Androl ; 19(3): 362-367, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-26975486

RESUMEN

This systematic review assessed the safety and efficacy of the disposable circumcision suture device (DCSD) and conventional circumcision (CC) in the treatment of redundant prepuce and phimosis. Two independent reviewers conducted a literature search for randomized controlled trials (RCTs) using the DCSD and CC for the treatment of redundant prepuce or phimosis in China and abroad. Nine RCTs (1898 cases) were included. Compared with the CC group, the DCSD group had a shorter operative time (standardized mean difference [SMD] = -21.44; 95% confidence intervals [95% CIs] [-25.08, -17.79]; P < 0.00001), shorter wound healing time (SMD = -3.66; 95% CI [-5.46, -1.85]; P < 0.0001), less intraoperative blood loss (SMD = -9.64; 95% CI [-11.37, -7.90]; P < 0.00001), better cosmetic penile appearance (odds ratio [OR] =8.77; 95% CI [5.90, 13.02]; P < 0.00001), lower intraoperative pain score, lower 24-h postoperative pain score, lower incidence of infection, less incision edema, and fewer adverse events. There were no differences between the CC and DCSD groups in the incidences of dehiscence, or hematoma. The results of this meta-analysis indicate that the DCSD appears to be safer and more effective than CC. However, additional high-quality RCTs with larger study populations are needed.


Asunto(s)
Circuncisión Masculina/instrumentación , Suturas , Equipos Desechables , Prepucio/cirugía , Humanos , Recién Nacido , Masculino , Dolor Postoperatorio , Pene/cirugía , Fimosis/cirugía
20.
Neural Plast ; 2016: 1923160, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27144032

RESUMEN

The intact crossed pathway via which the contralesional hemisphere responds to the ipsilesional somatosensory input has shown to be affected by unilateral stroke. The aim of this study was to investigate the plasticity of the intact crossed pathway in response to different intensities of stimulation in a rodent photothrombotic stroke model. Using optical intrinsic signal imaging, an overall increase of the contralesional cortical response was observed in the acute phase (≤48 hours) after stroke. In particular, the contralesional hyperactivation is more prominent under weak stimulations, while a strong stimulation would even elicit a depressed response. The results suggest a distinct stimulation-response pattern along the intact crossed pathway after stroke. We speculate that the contralesional hyperactivation under weak stimulations was due to the reorganization for compensatory response to the weak ipsilateral somatosensory input.


Asunto(s)
Isquemia Encefálica/diagnóstico por imagen , Lateralidad Funcional/fisiología , Plasticidad Neuronal/fisiología , Imagen Óptica/métodos , Accidente Cerebrovascular/diagnóstico por imagen , Animales , Isquemia Encefálica/fisiopatología , Modelos Animales de Enfermedad , Masculino , Ratas , Ratas Sprague-Dawley , Accidente Cerebrovascular/fisiopatología
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