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1.
Proc Natl Acad Sci U S A ; 120(22): e2221127120, 2023 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-37216515

RESUMO

CRISPR/Cas9 genome-editing tools have tremendously boosted our capability of manipulating the eukaryotic genomes in biomedical research and innovative biotechnologies. However, the current approaches that allow precise integration of gene-sized large DNA fragments generally suffer from low efficiency and high cost. Herein, we developed a versatile and efficient approach, termed LOCK (Long dsDNA with 3'-Overhangs mediated CRISPR Knock-in), by utilizing specially designed 3'-overhang double-stranded DNA (odsDNA) donors harboring 50-nt homology arm. The length of the 3'-overhangs of odsDNA is specified by the five consecutive phosphorothioate modifications. Compared with existing methods, LOCK allows highly efficient targeted insertion of kilobase-sized DNA fragments into the mammalian genomes with low cost and low off-target effects, yielding >fivefold higher knock-in frequencies than conventional homologous recombination-based approaches. This newly designed LOCK approach based on homology-directed repair is a powerful tool suitable for gene-sized fragment integration that is urgently needed for genetic engineering, gene therapies, and synthetic biology.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Animais , Sistemas CRISPR-Cas/genética , Sequência de Bases , Edição de Genes/métodos , DNA/genética , Recombinação Homóloga , Mamíferos/genética
2.
Nucleic Acids Res ; 51(19): 10428-10450, 2023 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-37739418

RESUMO

Arginine methylation, catalyzed by the protein arginine methyltransferases (PRMTs), is a common post-translational protein modification (PTM) that is engaged in a plethora of biological events. However, little is known about how the methylarginine-directed signaling functions in germline development. In this study, we discover that Prmt1 is predominantly distributed in the nuclei of spermatogonia but weakly in the spermatocytes throughout mouse spermatogenesis. By exploiting a combination of three Cre-mediated Prmt1 knockout mouse lines, we unravel that Prmt1 is essential for spermatogonial establishment and maintenance, and that Prmt1-catalyzed asymmetric methylarginine coordinates inherent transcriptional homeostasis within spermatogonial cells. In conjunction with high-throughput CUT&Tag profiling and modified mini-bulk Smart-seq2 analyses, we unveil that the Prmt1-deposited H4R3me2a mark is permissively enriched at promoter and exon/intron regions, and sculpts a distinctive transcriptomic landscape as well as the alternative splicing pattern, in the mouse spermatogonia. Collectively, our study provides the genetic and mechanistic evidence that connects the Prmt1-deposited methylarginine signaling to the establishment and maintenance of a high-fidelity transcriptomic identity in orchestrating spermatogonial development in the mammalian germline.


Assuntos
Epigenoma , Espermatogônias , Animais , Masculino , Camundongos , Arginina/metabolismo , Fertilidade/genética , Mamíferos/genética , Camundongos Knockout , Proteína-Arginina N-Metiltransferases/genética , Proteína-Arginina N-Metiltransferases/metabolismo , Espermatogônias/metabolismo
3.
J Med Virol ; 96(5): e29657, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38727035

RESUMO

The H1N1pdm09 virus has been a persistent threat to public health since the 2009 pandemic. Particularly, since the relaxation of COVID-19 pandemic mitigation measures, the influenza virus and SARS-CoV-2 have been concurrently prevalent worldwide. To determine the antigenic evolution pattern of H1N1pdm09 and develop preventive countermeasures, we collected influenza sequence data and immunological data to establish a new antigenic evolution analysis framework. A machine learning model (XGBoost, accuracy = 0.86, area under the receiver operating characteristic curve = 0.89) was constructed using epitopes, physicochemical properties, receptor binding sites, and glycosylation sites as features to predict the antigenic similarity relationships between influenza strains. An antigenic correlation network was constructed, and the Markov clustering algorithm was used to identify antigenic clusters. Subsequently, the antigenic evolution pattern of H1N1pdm09 was analyzed at the global and regional scales across three continents. We found that H1N1pdm09 evolved into around five antigenic clusters between 2009 and 2023 and that their antigenic evolution trajectories were characterized by cocirculation of multiple clusters, low-level persistence of former dominant clusters, and local heterogeneity of cluster circulations. Furthermore, compared with the seasonal H1N1 virus, the potential cluster-transition determining sites of H1N1pdm09 were restricted to epitopes Sa and Sb. This study demonstrated the effectiveness of machine learning methods for characterizing antigenic evolution of viruses, developed a specific model to rapidly identify H1N1pdm09 antigenic variants, and elucidated their evolutionary patterns. Our findings may provide valuable support for the implementation of effective surveillance strategies and targeted prevention efforts to mitigate the impact of H1N1pdm09.


Assuntos
Antígenos Virais , Vírus da Influenza A Subtipo H1N1 , Influenza Humana , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/imunologia , Humanos , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Influenza Humana/virologia , Influenza Humana/imunologia , Antígenos Virais/genética , Antígenos Virais/imunologia , Aprendizado de Máquina , Evolução Molecular , Epitopos/genética , Epitopos/imunologia , COVID-19/epidemiologia , COVID-19/prevenção & controle , COVID-19/virologia , COVID-19/imunologia , Pandemias/prevenção & controle , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , SARS-CoV-2/genética , SARS-CoV-2/imunologia
4.
Langmuir ; 40(18): 9688-9701, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38654502

RESUMO

Rubidium (Rb) and cesium (Cs) have important applications in highly technical fields. Salt lakes contain huge reserves of Rb and Cs with industrial significance, which can be utilized after extraction. In this study, a composite magnetic adsorbent (Fe3O4@ZIF-8@AMP, AMP = ammonium phosphomolybdate) was prepared and its adsorption properties for Rb+ and Cs+ were studied in simulated and practical brine. The structure of the adsorbent was characterized by SEM, XRD, N2 adsorption-desorption, FT-IR, and vibrating sample magnetometer (VSM). The adsorbent had good adsorption affinity for Rb+ and Cs+. The Langmuir model and pseudo-second-order dynamics described the adsorbing isotherm and kinetic dates, respectively. The adsorption capacity and adsorption rate of Fe3O4@ZIF-8@AMP were increased by 1.86- and 2.5-fold compared with those of powdered crystal AMP, owing to the large specific surface area and high dispersibility of the adsorbent in the solution. The adsorbent was rapidly separated from the solution within 17 s using an applied magnetic field owing to the good magnetic properties. The composite adsorbent selectively adsorbed Rb+ and Cs+ from the practical brine even in the presence of a large number of coexisting ions. The promising adsorbent can be used to extract Rb+ and Cs+ from aqueous solutions.

5.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 40(2): 202-207, 2023 Feb 10.
Artigo em Zh | MEDLINE | ID: mdl-36709941

RESUMO

OBJECTIVE: To analyze the correlation between the mRNA levels of breast cancer resistance protein (BCRP) and lung-specific X protein (LUNX) genes with pathological types and stages of patients with non-small cell lung cancer (NSCLC) and their significance for prognosis. METHODS: Eighty nine patients with NSCLC admitted to Huaihe Hospital of Henan University between June 2015 and June 2018 were recruited, with 55 patients with benign lung lesions admitted during the same period of time selected as the control group. The mRNA levels of BCRP and LUNX genes were detected in the peripheral blood samples from the two groups, and their correlation with the clinicopathological characteristics and prognosis of the patients was analyzed. RESULTS: The expression rates of BCRP and LUNX mRNA in the NSCLC group were significantly higher compared with the control group (P < 0.05). The level of BCRP mRNA of the NSCLC patients has correlated with the degree of differentiation and TNM staging (P < 0.05), but not with gender, age, smoking, pathological types and lymph node metastasis (P > 0.05). The level of LUNX mRNA of them has correlated with the degree of differentiation, TNM staging and lymph node metastasis (P < 0.05), but not with gender, age, smoking, and pathological types (P > 0.05). Compared with those with no expression, the overall survival rate of patients with BCRP and LUNX expression was significantly lower (P < 0.05). The degree of differentiation, TNM staging, lymph node metastasis, and expression of the BCRP and LUNX mRNA may all affect the prognosis of the patients. CONCLUSION: The levels of BCRP and LUNX mRNA in the peripheral blood of patients with NSCLC are significantly increased. The expression of BCRP mRNA is correlated with the degree of differentiation and TNM staging, whilst the expression of LUNX mRNA is correlated with the differentiation degree, TNM staging and lymph node metastasis. Both may be used as independent predictors for the prognosis of patients with NSCLC.


Assuntos
Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Carcinoma Pulmonar de Células não Pequenas , Glicoproteínas , Neoplasias Pulmonares , Fosfoproteínas , Humanos , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Glicoproteínas/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Metástase Linfática , Proteínas de Neoplasias/genética , Fosfoproteínas/genética , Prognóstico , RNA Mensageiro/genética
6.
Mar Policy ; 147: 105342, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36312743

RESUMO

The outbreak of COVID-19 pandemic all over the world has seriously affected seafarers' work and life. In this paper, we focus on the countermeasures of major countries and organizations on the seafarer shift matter during the pandemic period. And the target of this paper is to become useful in promoting the shift change of seafarers more smoothly. Policies are identified on the basis of a systematic review of importance in combination with a detailed analysis of the primary global and national policy initiatives. Findings suggest that the root cause of the international crew change crisis lies in the issues and deficiencies in the crew change system, economic security, seafarers' welfare, and seafarers' social security among other aspects. On this basis, this paper gives feasible suggestions in the respects of system innovation, economic security and welfare, social security system innovation and technical innovation.

7.
J Am Chem Soc ; 144(28): 12690-12697, 2022 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-35792375

RESUMO

Multi-module dCas9 engineering systems have been developed for controllable transcriptional manipulation such as chemical- or light-induced systems. However, there is still a need for a separate module that can be used for internal control over the CRISPR-dCas9 system. Here, we describe a multi-module CRISPR-dCas9 system in which a separate structured RNA was applied as a programmable component that could control dCas9-based gene regulation and achieved a higher activation efficiency than dCas9-VPR that is traditionally used. By introducing a microRNA sensor, we generated a dCas9-based transcriptional regulation platform that responded to endogenous microRNAs and allowed controllable activation of endogenous genes. Moreover, we applied the platform to selectively identify HCT116 cells in a cell mixture. This work provides a flexible platform for efficient and controllable gene regulation based on CRISPR-dCas9.


Assuntos
Sistemas CRISPR-Cas , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Sistemas CRISPR-Cas/genética , RNA/genética , Ativação Transcricional
8.
Analyst ; 147(9): 1892-1898, 2022 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-35348131

RESUMO

The development of a rapid and sensitive detection platform for DNA and DNA methylation in complex biological environments has attracted considerable attention. Herein, we describe a detection platform for p16 and p16 methylation in buffer and serum based on a single polymeric fluorescent microfiber waveguide with sandwich-structured hybridization designs. The target p16 could be captured by oligonucleotides conjugated on the surface of polymeric microfibers and oligonucleotides conjugated with gold nanoparticles, resulting in quenching the out-coupled tip emission of the microfiber waveguide. Then the restriction digestion enzyme HpaII was applied to specifically recognize the unmethylated 5'-CCGG-3' site and cut the formed sandwich structure. The gold nanoparticles could be removed from the surface of chitosan fiber so that the out-coupled tip emission of the polymeric fluorescent microfiber would be partially recovered. It is noteworthy that the proposed polymeric microfiber waveguide platform exhibited selective and sensitive detection of p16 with a low limit of 2 pM and excellent analytical performance of methylation as low as 5% difference. This strategy avoids the use of traditional PCR-based amplification and tedious operative processes, and we envisage that this technique could be extended to various DNA methylation analyses, which is meaningful for early clinical diagnosis of diseases.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Técnicas Biossensoriais/métodos , Metilação de DNA , Ouro/química , Nanopartículas Metálicas/química , Oligonucleotídeos , Polímeros/química
9.
Clin Exp Pharmacol Physiol ; 49(6): 686-695, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35320597

RESUMO

Diabetic nephropathy (DN), one of microvascular complications of diabetes mellitus, results in renal dysfunction and end-stage renal disease. Recently, endothelial-to-mesenchymal transition (EndMT) was reported to mediate glomerular endothelial dysfunction, therefore, participating in the progress of fibrosis in DN. As a special type of epithelial-to-mesenchymal transition, EndMT and epithelial-to-mesenchymal transition may share corporate modulators. It was reported that epidermal growth factor (EGF), latrophilin and seven transmembrane domain containing 1 (ELTD1) and signal transducer and activator of transcription 5A (STAT5A) participate in epithelial-to-mesenchymal transition in some situations. In this work, we proposed that STAT5A participated in high glucose-mediated EndMT via modulation of ELTD1 levels in DN. Our data indicated that hyperglycemia/high glucose-induced ELTD1 and EndMT in DN rats and hyperglycemic human glomerular endothelial cells (HGECs). Additionally, high glucose mediated STAT5A nuclear translocation in HGECs. High glucose-mediated EndMT was reversed by ELTD1 silencing. Moreover, STAT5A was found to be elevated in DN rats and hyperglycemic HGECs. The effect of high glucose-mediated increase of ELTD1 expression and EndMT was reversed by STAT5A silencing in vitro. Further, STAT5A overexpression enhanced ELTD1 levels and EndMT, which was inhibited by si-ELTD1. Chromatin immunoprecipitation (ChIP) and luciferase assay represented that STAT5A directly regulated ELTD1 transcription. Signal transducer and activator of transcription 5A directly regulated ELTD1 transcription, therefore, participating in high glucose-mediated EndMT in glomeruli of DN.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Animais , Diabetes Mellitus/metabolismo , Nefropatias Diabéticas/metabolismo , Células Endoteliais/metabolismo , Transição Epitelial-Mesenquimal/fisiologia , Glucose/metabolismo , Glucose/toxicidade , Ratos , Fator de Transcrição STAT5/metabolismo , Regulação para Cima
10.
Appl Opt ; 61(25): 7401-7408, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36256041

RESUMO

Streak tube imaging lidar (STIL) can obtain 4-D images of a target, and its performance is mainly determined by the streak tube sensor. To obtain a large field of view, we developed a streak tube with a photocathode length as large as 35.3 mm, which is larger than the commonly used ST-HDR (30 mm). At the same time, the temporal resolution and dynamic spatial resolution are 60 ps and 12 lp/mm, which are very suitable to obtain accurate target coordinates for 4-D imaging. In addition, the streak tube has a high detection sensitivity of 46 mA/W at 500 nm and, hence, prospects in remote imaging. To test the performance of the streak tube, an underwater STIL experiment was conducted. Echo signal processing was performed by means of a bandpass filter and a matched filter, and then the peak detection algorithm was used to reconstruct the image. The results indicate that a spatial resolution better than 9 mm is achieved in the limpid water with a depth of 20 m, and a range accuracy of 1 cm is achieved in the turbid water with a depth of 10 m. Such a performance suggests that the large-field streak tube is of great potential for underwater target imaging and other remote imaging applications.


Assuntos
Algoritmos , Tomografia Computadorizada por Raios X , Tomografia Computadorizada por Raios X/métodos , Processamento de Sinais Assistido por Computador , Água
11.
Water Sci Technol ; 86(12): 3051-3066, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36579869

RESUMO

The pure-MBBR process was applied to remove ammonia in a full-scale micro-polluted-water treatment plant with a daily treatment capacity of 260 × 104 m3/d, Guangdong, China. The relationship between treatment efficiency, physical and chemical properties and microbial diversity in the process of biofilm growth was explored, and the oxygen transfer model of biofilm was established. The results show that the effluent of two-stage pure MBBR process is stable and up to standard after 10 days' incubation. The nitrification loads of two-stage biofilm was stable on the 14th day. The biomass and biofilm thickness lagged behind the nitrification load, and reached a relatively stable level on the 28th day. The species richness of biofilm basically reached a stable level on the 21st day, and the microbial diversity of primary biofilm was higher. In the primary and secondary stage at different periods, the relative abundance of dominant nitrifying bacteria Nitrospira reaches 8.48-13.60%, 6.48-9.27%, and Nitrosomonas reaches 2.89-5.64%, 0.00-3.48%. The pure MBBR system mainly adopts perforated aeration. Through the cutting and blocking of bubbles by suspended carriers, the oxygen transfer rate of the system was greatly improved.


Assuntos
Biofilmes , Purificação da Água , Reatores Biológicos/microbiologia , Amônia/química , Nitrificação , Bactérias
12.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 39(11): 1283-1289, 2022 Nov 10.
Artigo em Zh | MEDLINE | ID: mdl-36317220

RESUMO

OBJECTIVE: To assess the association of polymorphisms of glutathione S-transferase P1 (GSTP1) and phospholipase C epsilon-1 (PLCE1) genes with the susceptibility of primary esophageal cancer and their interaction with environmental factors. METHODS: 162 patients with primary esophageal cancer and 162 healthy controls were recruited in this cross-sectional study. Basic information such as gender, age, history of smoking and alcohol consumption and family history of esophageal cancer were collected. Single nucleotide polymorphisms at A105G locus of GSTP1 gene and rs3765524, rs2274223 and rs3781264 loci of PLCE1 gene were detected. A logistic regression model was established to analyze the risk factors of esophageal cancer and the interaction among the factors. RESULTS: The proportions of individuals with smoking history, family history of esophageal cancer and hot diet in esophageal cancer group were higher than those in the control group (P<0.05). Conditional Logistic regression analysis showed that smoking, family history of esophageal cancer and GG genotype at the rs2274223 locus of PLCE1 gene were the risk factors for esophageal cancer (P<0.05), and AG/GG genotypes at the A105G locus of GSTP1 gene were the protective factors for esophageal cancer (P<0.05). In the two-factor interaction model, both AA genotype at A105G locus of GSTP1 gene and GG genotype at rs2274223 locus of PLCE1 gene had an interaction with smoking, and the risk of esophageal cancer has increased by 83.6% and 85.7%, respectively (P<0.05). AA genotype at A105G locus of GSTP1 gene, GG genotype at rs2274223 locus of PLCE1 gene and smoking constituted the best three-factor interaction model, and the risk of esophageal cancer has increased by 244.0% (P<0.05). Four-factor interaction model analysis showed that the risk of esophageal cancer among individuals with AA genotype at A105G locus of GSTP1 gene, GG genotype at rs2274223 locus of PLCE1 gene, smoking and family history of esophageal cancer has increased by 264.4% (P<0.05). CONCLUSION: The AG and GG genotypes at the A105G locus of GSTP1 gene are protective factors for esophageal cancer, and the GG genotype at rs2274223 locus of PLCE1 gene is a risk factor, both of them may interact with smoking and affect the susceptibility to esophageal cancer.


Assuntos
Neoplasias Esofágicas , Predisposição Genética para Doença , Humanos , Glutationa Transferase/genética , Estudos Transversais , Estudos de Casos e Controles , Neoplasias Esofágicas/genética , Polimorfismo de Nucleotídeo Único , Genótipo , Fatores de Risco , Glutationa S-Transferase pi/genética
13.
Med Sci Monit ; 27: e933454, 2021 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-34958655

RESUMO

BACKGROUND We aimed to evaluate the efficacy and safety of pneumatic trabeculoplasty (PNT) and selective laser trabeculoplasty (SLT) in the treatment of primary open-angle glaucoma (POAG) and ocular hypertension (OHT). MATERIAL AND METHODS We randomly divided 120 cases (120 eyes) of POAG or OHT into 2 groups: PNT and SLT. The changes in anterior chamber angle, intraocular pressure (IOP), treatment effect, macular retinal ganglion cell complex (GCC) thickness, visual field, adverse reactions, and complications were observed before and 3 months after treatment. RESULTS In the PNT group, the opening range of anterior chamber angle at 1 week, 2 weeks, 1 month, and 3 months after surgery was significantly larger than that before surgery. In the SLT group, the open range of anterior chamber angle was significantly less than that before surgery at 1 week and 2 weeks after surgery. The open range of anterior chamber angle in the PNT group was significantly larger than that in the SLT group at 1 week, 2 weeks, 1 month, and 3 months after surgery. The mean IOP of the 2 groups decreased significantly after surgery. The postoperative mean IOP of the SLT group was significantly higher than that of the PNT group, and the decrease of IOP in the PNT group was significantly greater than that of the SLT group. The effective rate of the PNT group was higher than that of the SLT group. CONCLUSIONS Both PNT and SLT can reduce the IOP of patients with POAG and OHT. PNT appears to have better short-term treatment efficiency than SLT.


Assuntos
Glaucoma de Ângulo Aberto/cirurgia , Hipertensão Ocular/cirurgia , Trabeculectomia/métodos , Adulto , Idoso , Feminino , Humanos , Terapia a Laser/métodos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
14.
J Am Chem Soc ; 142(27): 11857-11864, 2020 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-32476422

RESUMO

The use of low-intensity NIR light to operate molecular switches offers several potential advantages including enhanced penetration into bulk materials, in particular biological tissues, and reduced radiation damage due to the limited photon energies. The latter, however, pose a challenge for designing reasonably bistable systems. We have developed a general design strategy for direct one-photon NIR photoswitches based on negative photochromic dihydropyrenes carrying opposing strong donor-acceptor substituents either along the long axis of the molecule or across it. Thus, two series of 2,7- and 4,9-disubstituted dihydropyrenes were synthesized, and their photothermal properties investigated as a function of the type, strength, and position of the attached donor and acceptor substituents as well as the polarity of the environment. By shifting the excitation wavelength deep into the NIR, both NIR one-photon absorption cross-section and photoisomerization efficiency could be maximized while retaining a reasonable thermal stability of the metastable cyclophanediene isomer. Thus, the lowest optical transition was shifted beyond 900 nm, the NIR cross-section was enhanced by two orders of magnitude, and the thermal half-lives vary between milliseconds and hours. These unique features open up ample opportunities for noninvasive, optically addressable materials and material systems.

15.
Small ; 13(12)2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28084672

RESUMO

V2 O5 decorated carbon nanofibers (CNFs) are prepared and used as a multifunctional interlayer for a lithium-sulfur (Li-S) battery. V2 O5 anchored on CNFs can not only suppress the shuttle effect of polysulfide by the strong adsorption and redox reaction, but also work as a high-potential dam to restrain the self-discharge behavior in the battery. As a result, Li-S batteries with a high capacity and long cycling life can be stored and rested for a long time without obvious capacity fading.

16.
Appl Environ Microbiol ; 83(13)2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28432102

RESUMO

Species in the extremely thermophilic genus Caldicellulosiruptor can degrade unpretreated plant biomass through the action of multimodular glycoside hydrolases. To date, most focus with these bacteria has been on hydrolysis of glucans and xylans, while the biodegradation mechanism for arabinose-based polysaccharides remains unclear. Here, putative α-l-arabinofuranosidases (AbFs) were identified in Caldicellulosiruptor species by homology to less-thermophilic versions of these enzymes. From this screen, an extracellular XynF was determined to be a key factor in hydrolyzing α-1,2-, α-1,3-, and α-1,5-l-arabinofuranosyl residues of arabinose-based polysaccharides. Combined with a GH11 xylanase (XynA), XynF increased arabinoxylan hydrolysis more than 6-fold compared to the level seen with XynA alone, likely the result of XynF removing arabinofuranosyl side chains to generate linear xylans that were readily degraded. A second AbF, the intracellular AbF51, preferentially cleaved the α-1,5-l-arabinofuranosyl glycoside bonds within sugar beet arabinan. ß-Xylosidases, such as GH39 Xyl39B, facilitated the hydrolysis of arabinofuranosyl residues at the nonreducing terminus of the arabinose-branched xylo-oligosaccharides by AbF51. These results demonstrate the separate but complementary contributions of extracellular XynF and cytosolic AbF51 in processing the bioconversion of arabinose-containing oligosaccharides to fermentable monosaccharides.IMPORTANCE Degradation of hemicellulose, due to its complex chemical structure, presents a major challenge during bioconversion of lignocellulosic biomass to biobased fuels and chemicals. Degradation of arabinose-containing polysaccharides, in particular, can be a key bottleneck in this process. Among Caldicellulosiruptor species, the multimodular arabinofuranosidase XynF is present in only selected members of this genus. This enzyme exhibited high hydrolysis activity, broad specificity, and strong synergism with other hemicellulases acting on arabino-polysaccharides. An intracellular arabinofuranosidase, AbF51, occurs in all Caldicellulosiruptor species and, in conjunction with xylosidases, processes the bioconversion of arabinose-branched oligosaccharides to fermentable monosaccharides. Taken together, the data suggest that plant biomass degradation in Caldicellulosiruptor species involves extracellular XynF that acts synergistically with other hemicellulases to digest arabino-polysaccharides that are subsequently transported and degraded further by intracellular AbF51 to produce short-chain arabino sugars.


Assuntos
Arabinose/metabolismo , Proteínas de Bactérias/metabolismo , Firmicutes/enzimologia , Firmicutes/metabolismo , Glicosídeo Hidrolases/metabolismo , Polissacarídeos/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Firmicutes/química , Firmicutes/genética , Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/genética , Concentração de Íons de Hidrogênio , Peso Molecular , Especificidade por Substrato
17.
Molecules ; 22(5)2017 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-28445422

RESUMO

Qingwen Baidu Decoction (QBD) is an extraordinarily "cold" formula. It was traditionally used to cure epidemic hemorrhagic fever, intestinal typhoid fever, influenza, sepsis and so on. The purpose of this study was to discover relationships between the change of the constituents in different extracts of QBD and the pharmacological effect in a rat model of acute lung injury (ALI) induced by lipopolysaccharide (LPS). The study aimed to discover the changes in constituents of different QBD extracts and the pharmacological effects on acute lung injury (ALI) induced by LPS. The results demonstrated that high dose and middle dose of QBD had significantly potent anti-inflammatory effects and reduced pulmonary edema caused by ALI in rats (p < 0.05). To explore the underlying constituents of QBD, we assessed its influence of six different QBD extracts on ALI and analyzed the different constituents in the corresponding HPLC chromatograms by a Principal Component Analysis (PCA) method. The results showed that the pharmacological effect of QBD was related to the polarity of its extracts, and the medium polarity extracts E2 and E5 in particular displayed much better protective effects against ALI than other groups. Moreover, HPLC-DAD-ESI-MSn and PCA analysis showed that verbascoside and angoroside C played a key role in reducing pulmonary edema. In addition, the current study revealed that ethyl gallate, pentagalloylglucose, galloyl paeoniflorin, mudanpioside C and harpagoside can treat ALI mainly by reducing the total cells and infiltration of activated polymorphonuclear leukocytes (PMNs).


Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Anti-Inflamatórios/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Lesão Pulmonar Aguda/imunologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/química , Lipopolissacarídeos/farmacologia , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Pulmão/patologia , Masculino , Infiltração de Neutrófilos/efeitos dos fármacos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/metabolismo
18.
Acta Cardiol Sin ; 32(2): 194-204, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27122950

RESUMO

BACKGROUND: Impaired admission glucose (AG) is thought to significantly increase the risk of both early and late death with ST-segment elevation myocardial infarction (STEMI), especially for non-diabetic patients. However, several earlier studies contradict these relationships. Through our meta-analysis, we aimed to evaluate such a relation between impaired AG, the risk of death and STEMI. METHODS: We accessed PubMed, EMBASE, Web of Science, and the Cochrane Library and systematically searched their databases to identify all related prospective cohort studies. The relative risks (RRs) with their 95% confidence interval (CI) were pooled quantitatively. RESULTS: The pooled, unadjusted relative risks of early outcome events indicated that patients who had glucose concentrations ≥ the range of 6.1-11.1 mmol/L, had a 4.38-fold (95% CI, 3.23-5.94) higher early mortality. For late outcome events, the pooled unadjusted RR indicated patients who had glucose concentrations ≥ the range 7.8-11.1 mmol/L, and had a 2.69-fold (95% CI, 2.16-3.34) higher late mortality based on full participants, whereas patients had a 1.65-fold (95% CI, 1.33-2.04) higher late mortality based on based on in-hospital or 30-day survivors. CONCLUSIONS: In conclusion, the present meta-analysis demonstrated that impaired admission glucose may be an effective prognostic marker for significantly increased risk of early death. Regarding the long-term outcomes based on full population or early survival, high admission glucose also has a distinct but poorer prognostic impact on long-term mortality than early mortality. KEY WORDS: Admission glucose • Meta-analysis • Myocardial infarction • Non-diabetic.

19.
Transl Oncol ; 44: 101902, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38507924

RESUMO

OBJECTIVE: To investigate the vaginal and gut microbes changes during the carcinogenesis of cervical and the auxiliary diagnostic value. To investigate the effect of microbiome-specific metabolites butyric on cervical cancer cells. METHODS: We studied 416 vaginal 16S rRNA sequencing data and 116 gut sequencing data. Reads were processed using VSEARCH. We used Shannon index, Chao1 index, Simpson diversity index, ß diversity index, Linear discriminant analysis Effect Size (LEfSe), co-abundance network and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis to explore microbiome differences between groups. We constructed random forest models based on genus and verified its discriminant effect. Finally, we used the cell counting kit-8 (CCK-8) method to detect cell proliferation capacity and flow cytometry to detect apoptosis and induction of cell cycle progression. RESULTS: Compared to the non-cancerous population, patients with cervical cancer had unique microbial community characteristics in both vaginal and gut ecological niches. Our predictive model based on genus in two ecological regions achieved high accuracy in the diagnosis of cervical cancer (vaginal model AUC=91.58 %; gut model AUC=99.95 %). Butyric inhibited cervical cancer cell proliferation in a concentration-dependent manner and promoted apoptosis of cancer cells. CONCLUSION: Significant differences were found in vaginal and gut microbes in patients with cervical cancer compared to the non-cancerous population. The prediction models constructed at the genus level in both ecological sites have good diagnostic value. Microorganisms may be involved in cervical cancer progression in a metabolite-dependent way, and targeting butyric may provide therapeutic options for cervical cancer.

20.
Int J Oncol ; 65(1)2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38847233

RESUMO

Several studies have indicated that the gut microbiome and tumor microbiota may affect tumors. Emerging metabolomics research illustrates the need to examine the variations in microbial metabolite composition between patients with cancer and healthy individuals. Microbial metabolites can impact the progression of tumors and the immune response by influencing a number of mechanisms, including modulation of the immune system, cancer or immune­related signaling pathways, epigenetic modification of proteins and DNA damage. Microbial metabolites can also alleviate side effects and drug resistance during chemotherapy and immunotherapy, while effectively activating the immune system to exert tumor immunotherapy. Nevertheless, the impact of microbial metabolites on tumor immunity can be both beneficial and harmful, potentially influenced by the concentration of the metabolites or the specific cancer type. The present review summarizes the roles of various microbial metabolites in different solid tumors, alongside their influence on tumor immunity and treatment. Additionally, clinical trials evaluating the therapeutic effects of microbial metabolites or related microbes on patients with cancer have been listed. In summary, studying microbial metabolites, which play a crucial role in the interaction between the microbiota and tumors, could lead to the identification of new supplementary treatments for cancer. This has the potential to improve the effectiveness of cancer treatment and enhance patient prognosis.


Assuntos
Progressão da Doença , Microbioma Gastrointestinal , Imunoterapia , Neoplasias , Microambiente Tumoral , Humanos , Neoplasias/imunologia , Neoplasias/microbiologia , Neoplasias/terapia , Neoplasias/tratamento farmacológico , Microambiente Tumoral/imunologia , Microbioma Gastrointestinal/imunologia , Imunoterapia/métodos , Prognóstico
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