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1.
Am J Obstet Gynecol ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38642697

RESUMO

BACKGROUND: The gold-standard treatment for advanced pelvic organ prolapse is sacrocolpopexy. However, the preoperative features of prolapse that predict optimal outcomes are unknown. OBJECTIVE: This study aimed to develop a clinical prediction model that uses preoperative scores on the Pelvic Organ Prolapse Quantification examination to predict outcomes after minimally invasive sacrocolpopexy for stages 2, 3, and 4 uterovaginal prolapse and vaginal vault prolapse. STUDY DESIGN: A 2-institution database of pre- and postoperative variables from 881 cases of minimally invasive sacrocolpopexy was analyzed. Data from patients were analyzed in the following 4 groups: stage 2 uterovaginal prolapse, stage 3 to 4 uterovaginal prolapse, stage 2 vaginal vault prolapse, and stage 3 to 4 vaginal vault prolapse. Unsupervised machine learning was used to identify clusters and investigate associations between clusters and outcome. The k-means clustering analysis was performed with preoperative Pelvic Organ Prolapse Quantification points and stratified by previous hysterectomy status. The "optimal" surgical outcome was defined as postoperative Pelvic Organ Prolapse Quantification stage <2. Demographic variables were compared by cluster with Student t and chi-square tests. Odds ratios were calculated to determine whether clusters could predict the outcome. Age at surgery, body mass index, and previous prolapse surgery were used for adjusted odds ratios. RESULTS: Five statistically distinct prolapse clusters (phenotypes C, A, A>P, P, and P>A) were found. These phenotypes reflected the predominant region of prolapse (apical, anterior, or posterior) and whether support was preserved in the nonpredominant region. Phenotype A (anterior compartment prolapse predominant, posterior support preserved) was found in all 4 groups of patients and was considered the reference in the analysis. In 111 patients with stage 2 uterovaginal prolapse, phenotypes A and A>P (greater anterior prolapse than posterior prolapse) were found, and patients with phenotype A were more likely than those with phenotype A>P to have an optimal surgical outcome. In 401 patients with stage 3 to 4 uterovaginal prolapse, phenotypes C (apical compartment predominant, prolapse in all compartments), A, and A>P were found, and patients with phenotype A>P were more likely than those with phenotype A to have ideal surgical outcome. In 72 patients with stage 2 vaginal vault prolapse, phenotypes A, A>P, and P (posterior compartment predominant, anterior support preserved) were found, and those with phenotype A>P were less likely to have an ideal outcome than patients with phenotype A. In 297 patients with stage 3 to 4 vaginal vault prolapse, phenotypes C, A, and P>A (prolapse greater in posterior than in anterior compartment) were found, but there were no significant differences in rate of ideal outcome between phenotypes. CONCLUSION: Five anatomic phenotypes based on preoperative Pelvic Organ Prolapse Quantification scores were present in patients with stages 2 and 3 to 4 uterovaginal prolapse and vaginal vault prolapse. These phenotypes are predictive of surgical outcome after minimally invasive sacrocolpopexy. Further work needs to confirm the presence and predictive nature of these phenotypes. In addition, whether the phenotypes represent a progression of prolapse or discrete prolapse presentations resulting from different anatomic and life course risk profiles is unknown. These phenotypes may be useful in surgical counseling and planning.

2.
Soft Matter ; 20(9): 2024-2031, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38334705

RESUMO

Recently, colloids with an off-center fluorescent core and homogeneous composition have been developed to measure the rotational diffusivity of microparticles using 3D confocal microscopy in refractive index-matched suspensions. Here, we show that the same particles may be imaged using a standard fluorescence microscope to yield their rotational diffusion coefficients. Trajectories of the off-center core may be combined with known expressions for the correlation decay of particle orientations to determine an effective rotational diffusivity. For sedimented particles, we also find the rotational diffusivity about axes perpendicular and parallel to the interface by adding some bright field illumination and simultaneously tracking both the core and the particle. Trajectories for particles of different sizes yield excellent agreement with hydrodynamic models of rotational diffusion near flat walls, taking the sedimentation-diffusion equilibrium into account. Finally, we explore the rotational diffusivity of particles in crowded two-dimensional monolayers, finding a different reduction of the rotational motion about the two axes depending on the colloidal microstructure.

3.
Chem Biodivers ; : e202401165, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38973453

RESUMO

Bisindole compounds constitute a significant class of natural compounds distinguished by their characteristic bisindole structure and renowned for their anticancer properties. Over the past four decades, researchers have isolated 229 animal-derived bisindole compounds (ADBCs) from various animals. These compounds demonstrate a wide range of pharmacological properties, including cytotoxicity, antibacterial, antifungal, antiviral, and other activities. Notably, among these activities, cytotoxicity emerges as the most prominent characteristic of ADBCs. This review also summarizes the structureactivity relationship (SAR) studies associated with the cytotoxicity of these compounds and explores the druggability of these compounds. In summary, our objective is to provide an overview of the research progress concerning ADBCs, with the aim of fostering their continued development and utilization.

4.
Chem Biodivers ; 21(5): e202400098, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38462532

RESUMO

Curcumae Radix (CuR) is a traditional Chinese medicine that has been used in China for more than 1,000 years. It has the traditional efficacy of activating blood and relieving pain, promoting qi and relieving depression, clearing heart and cooling blood, and promoting gallbladder and removing jaundice. Based on this, many domestic and foreign scholars have conducted systematic studies on its chemical composition, pharmacological effects, toxicity and quality control. Currently, 250 compounds, mainly including terpenoids and curcuminoids, have been isolated and identified from CuR, which has pharmacological activities, including antitumor, anti-inflammatory and analgesic, antidepressant, hepatoprotective, hemostatic, hematopoietic, and treatment of diabetes mellitus. In modern clinical practice, CuR is widely used in the treatment of tumors, breast hyperplasia, hepatitis, and stroke. However, the generation of toxicity and clinical application of CuR and Caryophylli Flos, the determination of the concoction process of artifacts, the determination of specific Quality Marker, and the establishment of the quality control system of CuR, are problems that need to be solved urgently at present.


Assuntos
Curcuma , Controle de Qualidade , Humanos , Curcuma/química , Medicina Tradicional Chinesa , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/isolamento & purificação , Animais , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/isolamento & purificação
5.
J Basic Microbiol ; 64(6): e2300751, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38644586

RESUMO

NAD+-dependent (2 R,3 R)­2,3­butanediol dehydrogenase (BDH) from Neisseria gonorrhoeae (NgBDH) is a representative member of the medium-chain dehydrogenase/reductase (MDR) superfamily. To date, little information is available on the substrate binding sites and catalytic residues of BDHs from this superfamily. In this work, according to molecular docking studies, we found that conserved residues Phe120 and Val161 form strong hydrophobic interactions with both (2 R,3 R)­2,3­butanediol (RR-BD) and meso-2,3­butanediol (meso-BD) and that mutations of these residues to alanine or threonine impair substrate binding. To further evaluate the roles of these two residues, Phe120 and Val161 were mutated to alanine or threonine. Kinetic analysis revealed that, relative to those of wild type, the apparent KM values of the Phe120Ala mutant for RR-BD and meso-BD increased 36- and 369-fold, respectively; the catalytic efficiencies of this mutant with RR-BD and meso-BD decreased approximately 586- and 3528-fold, respectively; and the apparent KM values of the Val161Ala mutant for RR-BD and meso-BD increased 4- and 37-fold, respectively, the catalytic efficiencies of this mutant with RR-BD and meso-BD decreased approximately 3- and 28-fold, respectively. Additionally, the Val161Thr mutant slightly decreased catalytic efficiencies (twofold with RR-BD; 7.3-fold with meso-BD) due to an increase in KM (sixfold for RR-BD; 24-fold for meso-BD) and a slight increase (2.8-fold with RR-BD; 3.3-fold with meso-BD) in kcat. These findings validate the critical roles of Phe120 and Val161 of NgBDH in substrate binding and catalysis. Overall, the current study provides a better understanding of the substrate binding and catalysis of BDHs within the MDR superfamily.


Assuntos
Oxirredutases do Álcool , Butileno Glicóis , Simulação de Acoplamento Molecular , Mutagênese Sítio-Dirigida , Neisseria gonorrhoeae , Fenilalanina , Neisseria gonorrhoeae/enzimologia , Neisseria gonorrhoeae/genética , Neisseria gonorrhoeae/metabolismo , Oxirredutases do Álcool/genética , Oxirredutases do Álcool/metabolismo , Oxirredutases do Álcool/química , Cinética , Butileno Glicóis/metabolismo , Fenilalanina/metabolismo , Fenilalanina/genética , Sítios de Ligação , Especificidade por Substrato , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química , Valina/metabolismo , Valina/genética , Domínio Catalítico , Interações Hidrofóbicas e Hidrofílicas
6.
J Org Chem ; 88(11): 6633-6644, 2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37133412

RESUMO

Pyranones have raised great concerns owing to their considerable applications in a variety of sectors. However, the development of direct asymmetric allylation of 4-hydroxypyran-2-ones is still restricted. Herein, we present an effective iridium-catalyzed asymmetric functionalization technique for the synthesis of 4-hydroxypyran-2-one derivatives over direct and efficient catalytic asymmetric Friedel-Crafts-type allylation by using allyl alcohols. The allylation products could be obtained with good to high yields (up to 96%) and excellent enantioselectivities (>99% ee). Therefore, the disclosed technique provides a new asymmetric synthetic strategy to explore pyranone derivatives in depth, thus providing an interesting approach for global application and further utilization in organic synthesis and pharmaceutical chemistry.

7.
Chem Biodivers ; 20(12): e202301298, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37990607

RESUMO

Since ancient times, China has used natural medicine as the primary way to combat diseases and has a rich arsenal of natural medicines. With the progress of the times, the extraction of bioactive molecules from natural drugs has become the new development direction for natural medicines. Among the numerous natural drugs, Schisandrin C (Sch C), derived from Schisandra Chinensis (Turcz.) Baill. It has excellent potential for development and has been shown to possess various pharmacological properties, including hepatoprotective, antitumor and anti-inflammatory activities. Based on the biological properties of hepatoprotection, scholars have explored Sch C and its synthetic products in depth; some studies have shown that pentosidine has the effect of improving the symptoms of liver fibrosis and reducing the concentration of alanine transaminase (ALT) and aspartate aminotransferase (AST) in the serum of rats, which is an essential inspiration for the development of anti-liver fibrosis drugs. But more in vivo and ex vivo studies still need to be included. This paper focuses on Sch C's extraction and synthesis, biological activities and drug development progress. The future application prospects of Sch C are discussed to perfect its development work further.


Assuntos
Lignanas , Compostos Policíclicos , Schisandra , Ratos , Animais , Lignanas/farmacologia , Compostos Policíclicos/farmacologia , Ciclo-Octanos/farmacologia , Relação Estrutura-Atividade
8.
Zhongguo Zhong Yao Za Zhi ; 48(12): 3287-3293, 2023 Jun.
Artigo em Zh | MEDLINE | ID: mdl-37382013

RESUMO

This paper aimed to study the chemical constituents from the root bark of Schisandra sphenanthera. Silica, Sephadex LH-20 and RP-HPLC were used to separate and purify the 80% ethanol extract of S. sphenanthera. Eleven compounds were identified by ~1H-NMR, ~(13)C-NMR, ESI-MS, etc., which were 2-[2-hydroxy-5-(3-hydroxypropyl)-3-methoxyphenyl]-propane-1,3-diol(1), threo-7-methoxyguaiacylglycerol(2),4-O-(2-hydroxy-1-hydroxymethylethyl)-dihydroconiferylalcohol(3), morusin(4), sanggenol A(5), sanggenon I(6), sanggenon N(7), leachianone G(8),(+)-catechin(9), epicatechin(10), and 7,4'-dimethoxyisoflavone(11). Among them, compound 1 was a new compound, and compounds 2-9 were isolated from S. sphenanthera for the first time. Compounds 2-11 were subjected to cell viability assay, and the results revealed that compounds 4 and 5 had potential cytotoxicity, and compound 4 also had potential antiviral activity.


Assuntos
Catequina , Schisandra , Casca de Planta , Antivirais , Bioensaio , Fenóis
9.
Zhongguo Zhong Yao Za Zhi ; 48(24): 6676-6681, 2023 Dec.
Artigo em Zh | MEDLINE | ID: mdl-38212027

RESUMO

Nine compounds were isolated from the 90% ethanol extract of Salacia polysperma by silica gel, Sephadex LH-20 column chromatography, together with preparative HPLC methods. Based on HR-ESI-MS, MS, 1D and 2D NMR spectral analyses, the structures of the nine compounds were identified as 28-hydroxy wilforlide B(1), wilforlide A(2), 1ß,3ß-dihydroxyurs-9(11),12-diene(3),(-)-epicatechin(4),(+)-catechin(5),(-)-4'-O-methyl-ent-galloepicatechin(6), 3-hydroxy-1-(4-hydroxy-3-methoxy-phenyl)propan-1-one(7),(-)-(7S,8R)-4-hydroxy-3,3',5'-trimethoxy-8',9'-dinor-8,4'-oxyneoligna-7,9-diol-7'-aldehyde(8), and vanillic acid(9). Compound 1 is a new oleanane-type triterpene lactone. Compounds 1, 3, 4, 7-9 were isolated from the Salacia genus for the first time. All compounds were assayed for their α-glucosidase inhibitory activity. The results suggested that compound 8 exhibited moderate α-glucosidase inhibitory activity, with an IC_(50) value of 37.2 µmol·L~(-1), and the other compounds showed no α-glucosidase inhibitory activity.


Assuntos
Salacia , Triterpenos , Salacia/química , alfa-Glucosidases , Triterpenos/farmacologia , Espectroscopia de Ressonância Magnética , Etanol , Estrutura Molecular
10.
Zhongguo Zhong Yao Za Zhi ; 48(21): 5817-5821, 2023 Nov.
Artigo em Zh | MEDLINE | ID: mdl-38114177

RESUMO

Eight compounds were isolated from ethyl acetate fraction of 80% ethanol extract of the hulls of Garcinia mangostana by silica gel, Sephadex LH-20 column chromatography, as well as prep-HPLC methods. By HR-ESI-MS, MS, 1D and 2D NMR spectral analyses, the structures of the eight compounds were identified as 16-en mangostenone E(1), α-mangostin(2), 1,7-dihydroxy-2-(3-methy-lbut-2-enyl)-3-methoxyxanthone(3), cratoxyxanthone(4), 2,6-dimethoxy-para-benzoquinone(5), methyl orselinate(6), ficusol(7), and 4-(4-carboxy-2-methoxyphenoxy)-3,5-dimethoxybenzoic acid(8). Compound 1 was a new xanthone, and compound 4 was a xanthone dimer, compound 5 was a naphthoquinone. All compounds were isolated from this plant for the first time except compounds 2 and 3. Cytotoxic bioassay suggested that compounds 1, 2 and 4 possessed moderate cytotoxicity, suppressing HeLa cell line with IC_(50) va-lues of 24.3, 35.5 and 17.1 µmol·L~(-1), respectively. Compound 4 also could suppress K562 cells with an IC_(50) value of 39.8 µmol·L~(-1).


Assuntos
Antineoplásicos , Garcinia mangostana , Garcinia , Xantonas , Humanos , Garcinia mangostana/química , Células HeLa , Espectroscopia de Ressonância Magnética , Xantonas/farmacologia , Garcinia/química , Extratos Vegetais/química , Estrutura Molecular
11.
Gastroenterology ; 161(2): 653-668.e16, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33915173

RESUMO

BACKGROUND & AIMS: Pancreatic ductal adenocarcinoma (PDAC) is characterized by advanced disease stage at presentation, aggressive disease biology, and resistance to therapy, resulting in an extremely poor 5-year survival rate of <10%. PDAC is classified into transcriptional subtypes with distinct survival characteristics, although how these arise is not known. Epigenetic deregulation, rather than genetics, has been proposed to underpin progression, but exactly why is unclear and is hindered by the technical limitations of analyzing clinical samples. METHODS: We performed genome-wide epigenetic mapping of DNA modifications 5-methylcytosine and 5-hydroxymethylcytosine (5hmc) using oxidative bisulfite sequencing from formalin-embedded sections. We identified overlap with transcriptional signatures in formalin-fixed, paraffin-embedded tissue from resected patients, via bioinformatics using iCluster and mutational profiling and confirmed them in vivo. RESULTS: We found that aggressive squamous-like PDAC subtypes result from epigenetic inactivation of loci, including GATA6, which promote differentiated classical pancreatic subtypes. We showed that squamous-like PDAC transcriptional subtypes are associated with greater loss of 5hmc due to reduced expression of the 5-methylcytosine hydroxylase TET2. Furthermore, we found that SMAD4 directly supports TET2 levels in classical pancreatic tumors, and loss of SMAD4 expression was associated with reduced 5hmc, GATA6, and squamous-like tumors. Importantly, enhancing TET2 stability using metformin and vitamin C/ascorbic acid restores 5hmc and GATA6 levels, reverting squamous-like tumor phenotypes and WNT-dependence in vitro and in vivo. CONCLUSIONS: We identified epigenetic deregulation of pancreatic differentiation as an underpinning event behind the emergence of transcriptomic subtypes in PDAC. Our data showed that restoring epigenetic control increases biomarkers of classical pancreatic tumors that are associated with improved therapeutic responses and survival.


Assuntos
5-Metilcitosina/análogos & derivados , Biomarcadores Tumorais/genética , Carcinoma Ductal Pancreático/genética , Metilação de DNA , Proteínas de Ligação a DNA/metabolismo , Dioxigenases/metabolismo , Epigênese Genética , Fator de Transcrição GATA6/genética , Neoplasias Pancreáticas/genética , Transcrição Gênica , 5-Metilcitosina/metabolismo , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Ácido Ascórbico/farmacologia , Biomarcadores Tumorais/metabolismo , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/enzimologia , Carcinoma Ductal Pancreático/patologia , Diferenciação Celular , Linhagem Celular Tumoral , Metilação de DNA/efeitos dos fármacos , Proteínas de Ligação a DNA/genética , Dioxigenases/genética , Epigênese Genética/efeitos dos fármacos , Epigenoma , Epigenômica , Fator de Transcrição GATA6/metabolismo , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Metformina/farmacologia , Camundongos Nus , Camundongos Transgênicos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/enzimologia , Neoplasias Pancreáticas/patologia , Estudos Retrospectivos , Proteína Smad4/genética , Proteína Smad4/metabolismo , Transcrição Gênica/efeitos dos fármacos , Transcriptoma , Via de Sinalização Wnt/genética , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Sensors (Basel) ; 22(14)2022 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-35890828

RESUMO

Infrared images are robust against illumination variation and disguises, containing the sharp edge contours of objects. Visible images are enriched with texture details. Infrared and visible image fusion seeks to obtain high-quality images, keeping the advantages of source images. This paper proposes an object-aware image fusion method based on a deep residual shrinkage network, termed as DRSNFuse. DRSNFuse exploits residual shrinkage blocks for image fusion and introduces a deeper network in infrared and visible image fusion tasks than existing methods based on fully convolutional networks. The deeper network can effectively extract semantic information, while the residual shrinkage blocks maintain the texture information throughout the whole network. The residual shrinkage blocks adapt a channel-wise attention mechanism to the fusion task, enabling feature map channels to focus on objects and backgrounds separately. A novel image fusion loss function is proposed to obtain better fusion performance and suppress artifacts. DRSNFuse trained with the proposed loss function can generate fused images with fewer artifacts and more original textures, which also satisfy the human visual system. Experiments show that our method has better fusion results than mainstream methods through quantitative comparison and obtains fused images with brighter targets, sharper edge contours, richer details, and fewer artifacts.


Assuntos
Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Algoritmos , Artefatos , Humanos , Processamento de Imagem Assistida por Computador/métodos , Iluminação
13.
Curr Psychol ; : 1-14, 2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-35990203

RESUMO

This study investigats the relationships among positive emotions, perceived threats, protection motivation, coronavirus disease 2019 (COVID-19) vaccination intentions, quarantine-free travel intentions and COVID-19 protective behaviors in the context of quarantine-free travel. Data were collected from Singaporean tourists in Batam and Bintan of Indonesia using travel bubbles. A total of 387 respondents completed the questionnaires. The findings can help tourism managers create and implement market-driven service initiatives to increase positive emotions, protection motivation, and intentions to take quarantine-free travel and decrease perceived threats in order to enable tourists to have accurate COVID-19 protective behaviors.

14.
J Cell Physiol ; 236(8): 5921-5936, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33481281

RESUMO

Plant bugs (Miridae species) have become major agricultural pests that cause increasing and severe economic damage. Plant-mediated RNA interference (RNAi) is emerging as an eco-friendly, efficient, and reliable strategy for pest management. In this study, we isolated and characterized a lethal gene of Apolygus lucorum and named it Apolygus lucorum LIM (AlLIM), which produced A. lucorum mortality rates ranging from 38% to 81%. Downregulation of the AlLIM gene expression in A. lucorum by injection of a double-stranded RNA (dsRNA) led to muscle structural disorganization that resulted in metamorphosis deficiency and increased mortality. Then we constructed a plant expression vector that enabled transgenic cotton to highly and stably express dsRNA of AlLIM (dsAlLIM) by Agrobacterium-mediated genetic transformation. In the field bioassay, dsAlLIM transgenic cotton was protected from A. lucorum damage with high efficiency, with almost no detectable yield loss. Therefore, our study successfully provides a promising genetically modified strategy to overpower A. lucorum attack.


Assuntos
Gossypium/parasitologia , Heterópteros/genética , Insetos/genética , Interferência de RNA/imunologia , Animais , Plantas/parasitologia
15.
Protein Expr Purif ; 188: 105977, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34547433

RESUMO

Homoserine dehydrogenase (HSD), encoded by the hom gene, is a key enzyme in the aspartate pathway, which reversibly catalyzes the conversion of l-aspartate ß-semialdehyde to l-homoserine (l-Hse), using either NAD(H) or NADP(H) as a coenzyme. In this work, we presented the first characterization of the HSD from the symbiotic Polynucleobacter necessaries subsp. necessarius (PnHSD) produced in Escherichia coli. Sequence analysis showed that PnHSD is an ACT domain-containing monofunctional HSD with 436 amnio acid residues. SDS-PAGE and Western blot demonstrated that PnHSD could be overexpressed in E. coli BL21(DE3) cell as a soluble form by using SUMO fusion technique. It could be purified to apparent homogeneity for biochemical characterization. Size-exclusion chromatography revealed that the purified PnHSD has a native molecular mass of ∼160 kDa, indicating a homotetrameric structure. The oxidation activity of PnHSD was studied in this work. Kinetic analysis revealed that PnHSD displayed an up to 1460-fold preference for NAD+ over NADP+, in contrast to its homologs. The purified PnHSD displayed maximal activity at 35 °C and pH 11. Similar to its NAD+-dependent homolog, neither NaCl and KCl activation nor L-Thr inhibition on the enzymatic activity of PnHSD was observed. These results will contribute to a better understanding of the coenzyme specificity of the HSD family and the aspartate pathway of P. necessarius.


Assuntos
Ácido Aspártico/biossíntese , Proteínas de Bactérias/genética , Burkholderiaceae/enzimologia , Homosserina Desidrogenase/genética , NAD/metabolismo , Proteínas Recombinantes de Fusão/genética , Sequência de Aminoácidos , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/isolamento & purificação , Burkholderiaceae/química , Burkholderiaceae/genética , Cromatografia em Gel , Clonagem Molecular , Escherichia coli/genética , Escherichia coli/metabolismo , Euplotes/microbiologia , Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Homosserina/metabolismo , Homosserina Desidrogenase/biossíntese , Homosserina Desidrogenase/isolamento & purificação , Cinética , Peso Molecular , NADP/metabolismo , Multimerização Proteica , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/isolamento & purificação , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/genética , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/metabolismo , Simbiose/fisiologia
16.
Protein Expr Purif ; 186: 105909, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34022392

RESUMO

Gonorrhoea, caused by Neisseria gonorrhoeae, is a major global public health concern. Homoserine dehydrogenase (HSD), a key enzyme in the aspartate pathway, is a promising metabolic target against pathogenic infections. In this study, a monofunctional HSD from N. gonorrhoeae (NgHSD) was overexpressed in Escherichia coli and purified to >95% homogeneity for biochemical characterization. Unlike the classic dimeric structure, the purified recombinant NgHSD exists as a tetramer in solution. We determined the enzymatic activity of recombinant NgHSD for l-homoserine oxidation, which revealed that this enzyme was NAD+ dependent, with an approximate 479-fold (kcat/Km) preference for NAD+ over NADP+, and that optimal activity for l-homoserine oxidation occurred at pH 10.5 and 40 °C. At 800 mM, neither NaCl nor KCl increased the activity of NgHSD, in contrast to the behavior of several reported NAD+-independent homologs. Moreover, threonine did not markedly inhibit the oxidation activity of NgHSD. To gain insight into the cofactor specificity, site-directed mutagenesis was used to alter coenzyme specificity. The double mutant L45R/S46R, showing the highest affinity for NADP+, caused a shift in coenzyme preference from NAD+ to NADP+ by a factor of ~974, with a catalytic efficiency comparable with naturally occurring NAD+-independent homologs. Collectively, our results should allow the exploration of drugs targeting NgHSD to treat gonococcal infections and contribute to the prediction of the coenzyme specificity of novel HSDs.


Assuntos
Coenzimas , Homosserina Desidrogenase , NAD , Neisseria gonorrhoeae , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Coenzimas/química , Coenzimas/metabolismo , Escherichia coli/genética , Gonorreia/microbiologia , Homosserina Desidrogenase/genética , Homosserina Desidrogenase/metabolismo , Humanos , Mutagênese Sítio-Dirigida , NAD/química , NAD/metabolismo , NADP/química , NADP/metabolismo , Neisseria gonorrhoeae/enzimologia , Neisseria gonorrhoeae/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Especificidade por Substrato/genética
17.
J Clin Lab Anal ; 34(3): e23088, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31797450

RESUMO

BACKGROUND: Recently, several studies have investigated the relationship between Pre-miR-27a rs895819 polymorphism and risk of various cancers. However, the relationship between rs895819 and diffuse large B-cell lymphoma (DLBCL) has not been well known. METHODS: In this study, we conducted a case-control study to explore the role of Pre-miR-27a rs895819 in risk of DLBCL. The PCR-TaqMan and luciferase assays and in vitro experiments were used to evaluate polymorphism function. RESULTS: As a result, we found subjects carrying with rs895819 AG/GG genotype had a significantly decreased risk when compared with those carrying the AA genotype. Further qPCR assay showed that the DLBCL patients carrying AG/GG genotypes showed a lower level of mature miR-27a when compared with patients carrying AA genotype. Moreover, miR-27a levels were upregulated in DLBCL tissues compared with normal lymphoid tissues. Further in vitro experiments showed that miR-27a might function as an oncogene through target TGFBR1. In addition, TGFBR1 overexpression rescues effects of miR-27a inhibitor on DLBCL cells phenotypes. CONCLUSIONS: In conclusion, these findings indicate that rs895819 A > G might reduce the expression of mature miR-27a, and leading a higher level of TGFBR1, ultimately inhibiting the development of DLBCL.


Assuntos
Predisposição Genética para Doença , Linfoma Difuso de Grandes Células B/genética , MicroRNAs/genética , Polimorfismo de Nucleotídeo Único/genética , Precursores de RNA/genética , Sequência de Bases , Estudos de Casos e Controles , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Estudos de Associação Genética , Humanos , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Fenótipo , Precursores de RNA/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I/genética , Medição de Risco , Fatores de Risco
18.
Chemotherapy ; 64(3): 146-154, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31715603

RESUMO

OBJECTIVE: Colorectal cancer (CRC) remains a major cause of cancer-related death worldwide. Proteasome 26S subunit ATPase 2 (PSMC2) plays vital roles in regulating cell cycle and transcription and has been confirmed to be a gene potentially associated with some human tumors. However, the expression correlation and molecular mechanism of PSMC2 in CRC are still unclear. This study aimed to investigate the role of PSMC2 in malignant behaviors in CRC. METHODS: The high protein levels of PSMC2 in CRC samples were identified by tissue microarray analysis. Lentivirus was used to silence PSMC2 in HCT116 and RKO cells; MTT and colony formation assay were performed to determine cell proliferation. Wound healing and Transwell assay were used to detect cell migration and invasion. Flow cytometry assay was applied to detect cell cycle and apoptosis. RESULT: The results showed that, among the 96 CRC patients, the expression of PSMC2 was a positive correlation with the clinicopathological features of the patients with CRC. Furthermore, the low PSMC2 expression group showed a higher survival rate than the high PSMC2 expression group. The expression levels of PSMC2 in cancer tissue were dramatically upregulated compared with adjacent normal tissues. In vitro, shPSMC2 was designed to inhibit the expression of PSMC2 in CRC cells. Compared with shCtrl, silencing of PSMC2 significantly suppressed cell proliferation, decreased single cell colony formation, enhanced apoptosis, and accelerated G2 phase and/or S phase arrest. CONCLUSION: Survival analysis indicated that high expression of PSMC2 in the CRC samples was associated with poorer survival rate than low expression of PSMC2, while the anti-tumor effect of PSMC2 silencing was also confirmed at the cellular level in vitro. Our results suggested that PSMC2 potentially worked as a regulator for CRC, and the silencing of PSMC2 may be a therapeutic strategy for CRC.


Assuntos
ATPases Associadas a Diversas Atividades Celulares/metabolismo , Apoptose , Proliferação de Células , Neoplasias Colorretais/patologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Interferência de RNA , ATPases Associadas a Diversas Atividades Celulares/antagonistas & inibidores , ATPases Associadas a Diversas Atividades Celulares/genética , Idoso , Linhagem Celular Tumoral , Movimento Celular , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/mortalidade , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Prognóstico , Complexo de Endopeptidases do Proteassoma/genética , RNA Interferente Pequeno/metabolismo , Pontos de Checagem da Fase S do Ciclo Celular
19.
BMC Health Serv Res ; 18(1): 777, 2018 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-30326891

RESUMO

BACKGROUND: Problems of irrational antibiotic use by prescribers are ongoing and have escalated following reductions in the cost of essential drugs policy. In an attempt to improve prescribing practices for village doctors and rational use of essential drugs, a program designed to audit and monitor drug use was established. However, the effects of the program to control antibiotic resistance and changing the village doctors' prescribing behaviors remain largely unknown. This study measured the effect of the program on levels of antibiotic use. METHOD: Data was collected covering a 22-month period, before, during and after the program was implemented in rural clinics. Segmented regression analysis with interrupted time series (ITS) data was used to examine whether there had been a significant interaction with the onset of the program in September 2011 and levels of antibiotic use from November 2010 to August 2012. Both serial and 12-month lag autocorrelations were controlled for. RESULTS: A noticeable drop about 6.15% per month (95% CI: -13.36%; 1.06%, P = 0.089) for the antibiotic use in outpatients, which is lower of effect size assuming that the program has the immediate impact of the program were captured for the immediate effect of the program. Meanwhile, levels of antibiotic use would have continued to decrease by 1.12% per month (P = 0.034) as they did in the absence of the program. CONCLUSION: The central finding was that the prescription audit and feedback program was associated with significant decreases (P = 0.034) in antibiotic use after its implementation.


Assuntos
Antibacterianos/uso terapêutico , Revisão de Uso de Medicamentos , Uso Excessivo de Medicamentos Prescritos/prevenção & controle , Prescrições de Medicamentos/estatística & dados numéricos , Retroalimentação , Humanos , Análise de Séries Temporais Interrompida , Auditoria Médica , Padrões de Prática Médica , Uso Excessivo de Medicamentos Prescritos/estatística & dados numéricos , Análise de Regressão , Serviços de Saúde Rural/estatística & dados numéricos
20.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 38(6): 702-705, 2016 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-28065237

RESUMO

Objective To investigate the predictors for massive blood loss during posterior correction of congenital scoliosis in pre-school children. Methods Totally 124 children under six years of age,who received posterior correction of congenital scoliosis,were divided into two groups according to the ratio of intraoperative blood loss (BL) and estimated blood volume (EBV). Massive blood loss was defined as BL/EBV>0.15,and minor or moderate blood loss as BL/EBV≤0.15. All the records,including demographics,intraoperative fluids,pre- or postoperative laboratory parameters,and the length of hospital stay,were compared between these two groups. Results There were 57 children in the moderate or minor blood loss group and 67 children in the massive blood loss group. When compared with moderate or minor blood loss group,children in massive blood loss group had significantly lower body weight,shorter body height,longer anesthesia period,and more autologous or allogeneic transfusion (P<0.05). Binary Logistic regression analysis showed that body weight lower than 15 kg was the independent predictor for massive blood loss (OR=0.435,95% CI=0.197-0.962). Conclusions The incidence of massive blood loss is about 54% in children under six years of age who have received posterior correction of congenital scoliosis. The body weight of lower than 15 kg is an independent predictor for massive blood loss during the surgery.


Assuntos
Perda Sanguínea Cirúrgica , Escoliose/cirurgia , Fusão Vertebral/efeitos adversos , Criança , Humanos , Tempo de Internação , Estudos Retrospectivos , Resultado do Tratamento
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