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1.
Neurosurg Rev ; 47(1): 62, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38263482

RESUMO

At present, percutaneous surgery is widely used to treat thoracolumbar fractures. However, the actual safety, feasibility, and effectiveness of percutaneous surgery are not clear. Through systematic review and meta-analysis, we compared the efficacies of percutaneous pedicle screw fixation and open pedicle screw fixation in the treatment of thoracolumbar fractures without nerve root symptoms. We systematically searched the PubMed, Embase, and Cochrane libraries for articles published on or before June 2023. All results were evaluated by standard methods recommended for meta-analysis, continuous data were expressed by standard mean differences (SMDs), and binary variables were analyzed by odds ratios (ORs) and 95% confidence intervals (95% CIs). We also explored the main sources of heterogeneity and the stability of the results through sensitivity analysis, Begg's funnel plots, and Egger's test. Thirty-five cohort studies with a total of 3039 patients were included. The study found that patients who undergo percutaneous approaches have less intraoperative blood loss (IBL), shorter length of hospital stay (LOS), shorter operation time, and shorter incision. Moreover, percutaneous approaches had more advantages in terms of visual analog scale (VAS) scores, Oswestry Disability Index (ODI) scores, and infection rates. However, there was no significant difference in anterior vertebral body height (AVB), Cobb angle (CA), or screw errors between the two groups. In the long run, the clinical and surgical results of the percutaneous approach are better than those of the open approach, but the radiological results of both operations do not seem to show an advantage for any specific approach. Because of publication bias and heterogeneity, our findings must be interpreted with caution. However, this paper will provide some support for clinicians to choose suitable surgical methods for the treatment of thoracolumbar fractures.


Assuntos
Perda Sanguínea Cirúrgica , Parafusos Pediculares , Humanos , Estudos de Coortes , Tempo de Internação , Razão de Chances
2.
Neurosurg Rev ; 47(1): 140, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38578529

RESUMO

In recent years, nonsteroidal anti-inflammatory drug (NSAIDs), which are considered to affect the prognosis of spinal surgery, have been widely used in perioperative analgesia in spinal surgery, but the relationship between these two factors remains unclear. The purpose of this study was to explore the effect of perioperative use of NSAIDs on the prognosis of patients treated with spinal surgery. We systematically searched PubMed, Embase, and Cochrane Library for relevant articles published on or before July 14, 2023. We used a random-effect model for the meta-analysis to calculate the standardized mean difference (SMD) with a 95% confidence interval (CI). Sensitivity analyses were conducted to analyze stability. A total of 23 randomized clinical trials including 1457 participants met the inclusion criteria. Meta-analysis showed that NSAIDs were significantly associated with postoperative morphine use (mg) (SMD = -0.90, 95% CI -1.12 to -0.68) and postoperative pain (SMD = -0.71, 95% CI -0.85 to -0.58). These results were further confirmed by the trim-and-fill procedure and leave-one-out sensitivity analyses. The current study shows that perioperative use of NSAIDs appears to be an important factor in reducing postoperative pain and morphine use in patients undergoing spinal surgery. However, well-designed, high-quality randomized controlled trials (RCTs) are still required.


Assuntos
Anti-Inflamatórios não Esteroides , Dor Pós-Operatória , Coluna Vertebral , Humanos , Anti-Inflamatórios não Esteroides/uso terapêutico , Derivados da Morfina/uso terapêutico , Dor Pós-Operatória/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto , Coluna Vertebral/cirurgia
3.
Crit Rev Eukaryot Gene Expr ; 33(8): 31-39, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37606162

RESUMO

Zinc finger CCHC-type containing 4 (ZCCHC4), RNA binding protein, has been reported to mediate rRNA methylation and affect tumor cell proliferation. However, the role of ZCCHC4 in the regulation of osteosarcoma (OS) remains unknown. ZCCHC4 was highly expressed in OS tissues and cell lines. Overexpression or silencing of ZCCHC4 promoted or inhibited cell proliferation, epithelial-mesenchymal transition (EMT), and motility. Additionally, we proved that ZCCHC4 facilitates OS progression through upregulating integrin ß1 (ITGB1). In the animal model, ZCCHC4 knockdown reduced OS tumor growth and metastases in vivo. Our findings showed that ZCCHC4 promoted the progression of OS through upregulating ITGB1 and suggested that inhibition of ZCCHC4 could be a novel therapeutic strategy for OS.


Assuntos
Neoplasias Ósseas , Osteossarcoma , Animais , Integrina beta1/genética , Osteossarcoma/genética , Linhagem Celular , Proliferação de Células/genética , Neoplasias Ósseas/genética
4.
Microb Cell Fact ; 22(1): 127, 2023 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-37443029

RESUMO

BACKGROUND: Streptomyces are well known for their potential to produce various pharmaceutically active compounds, the commercial development of which is often limited by the low productivity and purity of the desired compounds expressed by natural producers. Well-characterized promoters are crucial for driving the expression of target genes and improving the production of metabolites of interest. RESULTS: A strong constitutive promoter, stnYp, was identified in Streptomyces flocculus CGMCC4.1223 and was characterized by its effective activation of silent biosynthetic genes and high efficiency of heterologous gene expression. The promoter stnYp showed the highest activity in model strains of four Streptomyces species compared with the three frequently used constitutive promoters ermEp*, kasOp*, and SP44. The promoter stnYp could efficiently activate the indigoidine biosynthetic gene cluster in S. albus J1074, which is thought to be silent under routine laboratory conditions. Moreover, stnYp was found suitable for heterologous gene expression in different Streptomyces hosts. Compared with the promoters ermEp*, kasOp*, and SP44, stnYp conferred the highest production level of diverse metabolites in various heterologous hosts, including the agricultural-bactericide aureonuclemycin and the antitumor compound YM-216391, with an approximately 1.4 - 11.6-fold enhancement of the yields. Furthermore, the purity of tylosin A was greatly improved by overexpressing rate-limiting genes through stnYp in the industrial strain. Further, the yield of tylosin A was significantly elevated to 10.30 ± 0.12 g/L, approximately 1.7-fold higher than that of the original strain. CONCLUSIONS: The promoter stnYp is a reliable, well-defined promoter with strong activity and broad suitability. The findings of this study can expand promoter diversity, facilitate genetic manipulation, and promote metabolic engineering in multiple Streptomyces species.


Assuntos
Produtos Biológicos , Streptomyces , Tilosina/metabolismo , Produtos Biológicos/metabolismo , Streptomyces/genética , Streptomyces/metabolismo , Regiões Promotoras Genéticas , Família Multigênica
5.
Neurosurg Rev ; 46(1): 159, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37392260

RESUMO

Recurrent lumbar disc herniation (rLDH) is one of the most serious complications and major causes of surgical failure and paralysis following percutaneous endoscopic lumbar discectomy (PELD). There are reports in the literature on the identification of risk factors associated with rLDH; however, the results are controversial. Therefore, we conducted a meta-analysis to identify risk factors for rLDH among patients following spinal surgery. PubMed, EMBASE, and the Cochrane Library were searched without language restrictions from inception to April 2018 for studies reporting risk factors for LDH recurrence after PELD. MOOSE guidelines were followed in this meta-analysis. We used a random effects model to aggregate odds ratios (ORs) with 95% confidence intervals (CIs). The evidence of observational studies was classified into high quality (class I), medium quality (class II/III), and low quality (class IV) based on the P value of the total sample size and heterogeneity between studies. Fifty-eight studies were identified with a mean follow-up of 38.8 months. Studies with high-quality (class I) evidence showed that postoperative LDH recurrence after PELD was significantly correlated with diabetes (OR, 1.64; 95% CI, 1.14 to 2.31), the protrusion type LDH (OR, 1.62; 95% CI, 1.02 to 2.61), and less experienced surgeons (OR, 1.54; 95% CI, 1.10 to 2.16). Studies with medium-quality (class II or III) evidence showed that postoperative LDH recurrence was significantly correlated with advanced age (OR, 1.11; 95% CI, 1.05 to 1.19), Modic changes (OR, 2.23; 95% CI, 1.53 to 2.29), smoking (OR, 1.31; 95% CI, 1.00 to 1.71), no college education (OR, 1.56; 95% CI, 1.05 to 2.31), obesity (BMI ≥ 25 kg/m2) (OR, 1.66; 95% CI, 1.11 to 2.47), and inappropriate manual labor (OR, 2.18; 95% CI, 1.33 to 3.59). Based on the current literature, eight patient-related and one surgery-related risk factor are predictors of postoperative LDH recurrence after PELD. These findings may help clinicians raise awareness of early intervention for patients at high risk of LDH recurrence after PELD.


Assuntos
Discotomia Percutânea , Deslocamento do Disco Intervertebral , Humanos , Deslocamento do Disco Intervertebral/cirurgia , Vértebras Lombares/cirurgia , Discotomia , Fatores de Risco , Estudos de Coortes
6.
Int J Mol Sci ; 24(19)2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37834300

RESUMO

Food-derived peptides have good antioxidant activity and are highly safe for humans; consequently, there has been continuous growth in research on antioxidants, with potential applications in food, medicine, cosmetics, and other fields. Among food-derived peptides, walnut-derived peptides have attracted increasing attention as food-derived peptides rich in eight essential amino acids. This review summarizes the progress made in the development and identification of antioxidant peptides in walnut proteins. This article mainly describes the interaction between reactive oxygen species and cellular antioxidant products, modulation of enzyme content and activity, and regulation of the redox signaling pathways and analyzes the mechanisms of reduction in oxidative stress. Finally, the complex structure-activity relationships of walnut-derived peptides are analyzed based on their amino acid composition and secondary structure of the polypeptides. This review provides a theoretical basis for the production of walnut-derived antioxidant peptides and could help promote the development of the walnut industry.


Assuntos
Antioxidantes , Juglans , Humanos , Antioxidantes/química , Juglans/química , Nozes/química , Estresse Oxidativo , Peptídeos/química
7.
Molecules ; 29(1)2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-38202799

RESUMO

Litsea cubeba is a characteristic woody oil resource in Hunan. As a solid waste of woody oil resources, Litsea cubeba kernels are rich in Litsea cubeba kernel oil with a carbon chain length of C10-12 fatty acid. In this work, aliphatic hydroxamic acids (AHAs) with carbon chain lengths of C10-12 were prepared from Litsea cubeba kernel oil via methylation and hydroximation reactions. The adsorption and hydrophobicity mechanism of AHA towards wolframite was explored by contact angle, zeta potential, Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The flotation results demonstrated that AHA was a superior collector than the traditional collector such as benzoyl hydroxamic acid (BHA). Zeta potential and contact angle results have shown that AHA was adsorbed on the surface of the Fe(III)-activated wolframite in its anionic form, which significantly improved the surface hydrophobicity of wolframite. FTIR and XPS revealed that AHA was chemically adsorbed on the surface of Fe(III)-activated wolframite in the form of a five-member ring, which made the hydrophobic chain reach into the solution, come in contact with bubbles, and achieve flotation separation.

8.
Environ Geochem Health ; 45(7): 5093-5107, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37069329

RESUMO

Several studies have assessed the influence of several often-ignored environmental factors on low back pain (LBP), but the effects of environmental polycyclic aromatic hydrocarbon (PAH) exposure on LBP are unclear. During the 2001-2004 cycle of the National Health and Nutrition Examination Survey (NHANES), our study was given to a representative sample of US participants older than 20 (N = 2743). Environmental PAH exposure was calculated using urinary PAH metabolite concentrations. Weighted logistic regression was performed to assess the connection between PAH levels and LBP, with mediation analysis utilised to explore the underlying mechanism. Levels of 1-hydroxynaphthalene (1-OHNa), 2-hydroxynaphthalene (2-OHNa) and total PAHs had a statistically significant positive association with LBP. The odds ratios per 1-unit increase for log-transformed levels of urinary 1-OHNa, 2-OHNa, and total PAHs with LBP were 1.01 (95% CI 1.02-1.19), 1.19 (95% CI 1.04-1.36) and 1.16 (95% CI 1.03-1.32), respectively. The results revealed a strong dose-response association between 1-OHNa, 2-OHNa, total PAHs, and LBP risk. Subgroup analysis indicated that 2&3-OHPh may increase the risk of LBP in the lower family income subgroup. Gamma-glutamyl transaminase (GGT), known as a biomarker of oxidative stress, was strongly related to PAHs. The relationship between total PAHs and LBP was mediated in part by GGT. Our study demonstrates associations between environmental PAH exposure and LBP that need more research to determine the precise effects of various PAH compounds on LBP.


Assuntos
Dor Lombar , Hidrocarbonetos Policíclicos Aromáticos , Humanos , Hidrocarbonetos Policíclicos Aromáticos/análise , Inquéritos Nutricionais , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Biomarcadores/urina
9.
J Biol Chem ; 296: 100655, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33901491

RESUMO

Highly conserved amino acids are generally anticipated to have similar functions across a protein superfamily, including that of the P2X ion channels, which are gated by extracellular ATP. However, whether and how these functions are conserved becomes less clear when neighboring amino acids are not conserved. Here, we investigate one such case, focused on the highly conserved residue from P2X4, E118 (rat P2X4 numbering, rP2X4), a P2X subtype associated with human neuropathic pain. When we compared the crystal structures of P2X4 with those of other P2X subtypes, including P2X3, P2X7, and AmP2X, we observed a slightly altered side-chain orientation of E118. We used protein chimeras, double-mutant cycle analysis, and molecular modeling to reveal that E118 forms specific contacts with amino acids in the "beak" region, which facilitates ATP binding to rP2X4. These contacts are not present in other subtypes because of sequence variance in the beak region, resulting in decoupling of this conserved residue from ATP recognition and/or channel gating of P2X receptors. Our study provides an example of a conserved residue with a specific role in functional proteins enabled by adjacent nonconserved residues. The unique role established by the E118-beak region contact provides a blueprint for the development of subtype-specific inhibitors of P2X4.


Assuntos
Trifosfato de Adenosina/metabolismo , Ativação do Canal Iônico , Receptores Purinérgicos P2X4/metabolismo , Sequência de Aminoácidos , Animais , Eletrofisiologia , Células HEK293 , Humanos , Modelos Moleculares , Conformação Proteica , Homologia de Sequência , Peixe-Zebra
10.
J Biol Chem ; 297(4): 101125, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34461094

RESUMO

Transient receptor potential canonical (TRPC) channels, as important membrane proteins regulating intracellular calcium (Ca2+i) signaling, are involved in a variety of physiological and pathological processes. Activation and regulation of TRPC are more dependent on membrane or intracellular signals. However, how extracellular signals regulate TRPC6 function remains to be further investigated. Here, we suggest that two distinct small molecules, M085 and GSK1702934A, directly activate TRPC6, both through a mechanism of stimulation of extracellular sites formed by the pore helix (PH) and transmembrane (TM) helix S6. In silico docking scanning of TRPC6 identified three extracellular sites that can bind small molecules, of which only mutations on residues of PH and S6 helix significantly reduced the apparent affinity of M085 and GSK1702934A and attenuated the maximal response of TRPC6 to these two chemicals by altering channel gating of TRPC6. Combing metadynamics, molecular dynamics simulations, and mutagenesis, we revealed that W679, E671, E672, and K675 in the PH and N701 and Y704 in the S6 helix constitute an orthosteric site for the recognition of these two agonists. The importance of this site was further confirmed by covalent modification of amino acid residing at the interface of the PH and S6 helix. Given that three structurally distinct agonists M085, GSK1702934A, and AM-0883, act at this site, as well as the occupancy of lipid molecules at this position found in other TRP subfamilies, it is suggested that the cavity formed by the PH and S6 has an important role in the regulation of TRP channel function by extracellular signals.


Assuntos
Sinalização do Cálcio , Ativação do Canal Iônico/efeitos dos fármacos , Simulação de Dinâmica Molecular , Canal de Cátion TRPC6/química , Canal de Cátion TRPC6/metabolismo , Células HEK293 , Humanos , Estrutura Secundária de Proteína , Canal de Cátion TRPC6/genética
11.
Appl Environ Microbiol ; 88(6): e0203521, 2022 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-35108072

RESUMO

Pyridomycin, a cyclodepsipeptide with potent antimycobacterial activity, specifically inhibits the InhA enoyl reductase of Mycobacterium tuberculosis. Structure-activity relationship studies indicated that the enolic acid moiety in the pyridomycin core system is an important pharmacophoric group, and the natural configuration of the C-10 hydroxyl contributes to the bioactivity of pyridomycin. The ring structure of pyridomycin was generated by the nonribosomal peptide synthetase (NRPS) and polyketide synthase (PKS) hybrid system (PyrE-PyrF-PyrG). Bioinformatics analysis reveals that short-chain dehydrogenase/reductase (SDR) family protein Pyr2 functions as a 3-oxoacyl acyl carrier protein (ACP) reductase in the pyridomycin pathway. Inactivation of pyr2 resulted in accumulation of pyridomycin B, a new pyridomycin analogue featured with enol moiety in pyridyl alanine moiety and a saturated 3-methylvaleric acid group. The elucidated structure of pyridomycin B suggests that rather than functioning as a post-tailoring enzyme, Pyr2 catalyzes ketoreduction to form the C-10 hydroxyl group in pyridyl alanine moiety and the double bond formation of the enolic acid moiety derived from isoleucine when the intermediate assembled by PKS-NRPS machinery is still tethered to the last NRPS module in a special energy-saving manner. Ser-His-Lys residues constitute the active site of Pyr2, which is different from the typically conserved Tyr-based catalytic triad in the majority of SDRs. Site-directed mutation identified that His154 in the active site is a critical residue for pyridomycin B production. These findings will improve our understanding of pyridomycin biosynthetic logic, identify the missing link for the double bound formation of enol ester in pyridomycin, and enable the creation of chemical diversity of pyridomycin derivatives. IMPORTANCE Tuberculosis (TB) is one of the world's leading causes of death by infection. Recently, pyridomycin, the antituberculous natural product from Streptomyces has garnered considerable attention for being determined as a target inhibitor of InhA enoyl reductase of Mycobacterium tuberculosis. In this study, we report a new pyridomycin analogue from mutant HTT12, demonstrate the essential role of a previously ignored gene pyr2 in pyridomycin biosynthetic pathway, and imply that Pyr2 functions as a trans ketoreductase (KR) contributing to the formation of functional groups of pyridomycin utilizing a distinct catalytic mechanism. As enol moiety are important for pharmaceutical activities of pyridomycin, our work would expand our understanding of the mechanism of SDR family proteins and set the stage for future bioengineering of new pyridomycin derivatives.


Assuntos
Mycobacterium tuberculosis , Streptomyces , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/metabolismo , Oligopeptídeos , Oxirredutases/metabolismo , Peptídeo Sintases/genética , Peptídeo Sintases/metabolismo , Policetídeo Sintases/genética , Policetídeo Sintases/metabolismo , Streptomyces/metabolismo
12.
Arch Pharm (Weinheim) ; 355(7): e2100465, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35415908

RESUMO

A series of novel pyrazolo[3,4-b]pyridine derivatives were designed, synthesized, and biologically evaluated for anti-lung cancer activity. Structure-activity relationship and AutoGPA models were constructed based on the in vitro antiproliferative potency of the compounds against a human lung adenocarcinoma cell line (A549). Compound 9d exhibits improved potency for A549 cell growth inhibition (3.06 ± 0.05 µM) compared with A-769662 (45.29 ± 2.14 µM). Compound 9d can elevate the phosphorylation levels of adenosine monophosphate-activated protein kinase (AMPK) and its substrate acetyl-CoA carboxylase and reduce the level of phosphorylated ribosomal S6 kinase (p-70S6K) at 1 µM, which is comparable to the activity of A-769662 at 20 µM. 9d induced G2/M cell cycle arrest, which was rescued when co-incubated with "Compound C," a potent AMPK inhibitor. Taken together, compound 9d showed potential anti-lung cancer activity via inducing cell cycle arrest by regulation of the AMPK/70S6K pathway in A549 cells, which could provide a new lead for the discovery of anti-lung cancer agents.


Assuntos
Proteínas Quinases Ativadas por AMP , Antineoplásicos , Proteínas Quinases Ativadas por AMP/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Estrutura Molecular , Piridinas/química , Relação Estrutura-Atividade
13.
Molecules ; 27(24)2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36558013

RESUMO

The aim of this study was to devise a method to protect Chinese cabbage (Brassica chinensis) and lettuce (Lactuca sativa) from bacterial-disease-induced damage during storage. Thus, the potential of rhapontigenin as a quorum sensing (QS) inhibitor against Pectobacterium carotovorum subsp. carotovorum (P. carotovorum) was evaluated. The QS inhibitory effects of rhapontigenin were confirmed by significant inhibition of the production of violacein in Chromobacterium violaceum CV026 (C. violaceum, CV026). The inhibitory effects of rhapontigenin on the motility, exopolysaccharide (EPS) production, biofilm formation and virulence−exoenzyme synthesis of P. carotovorum were investigated. Acyl-homoserine lactones (AHLs) were quantified using liquid chromatography−mass spectrometry (LC−MS). The inhibitory effects of rhapontigenin on the development of biofilms were observed using fluorescence microscopy and scanning electron microscopy (SEM). A direct-inoculation assay was performed to investigate the QS inhibitory effects of rhapontigenin on P. carotovorum in Chinese cabbage and lettuce. Our results demonstrated that rhapontigenin exhibited significant inhibition (p < 0.05) of the motility, EPS production, biofilm formation, virulence−exoenzyme synthesis and AHL production of P. carotovorum. Additionally, the result of the direct-inoculation assay revealed that rhapontigenin might provide vegetables with significant shelf-life extension and prevent quality loss by controlling the spread of soft-rot symptoms. Consequently, the study provided a significant insight into the potential of rhapontigenin as a QS inhibitor against P. carotovorum.


Assuntos
Brassica , Percepção de Quorum , Verduras , Pectobacterium carotovorum , Biofilmes , Chromobacterium , Antibacterianos/farmacologia
14.
Arch Pharm (Weinheim) ; 354(7): e2000458, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33683726

RESUMO

Adenosine monophosphate-activated protein kinase (AMPK) plays a key role in maintaining whole-body homeostasis and has been regarded as a therapeutic target for the treatment of diabetic nephropathy (DN). Herein, a series of 1,2,4-oxadiazole-containing pyrazolo[3,4-b]pyridinone derivatives is reported as AMPKɑ1ß1γ1 activators. The in vitro biological assay demonstrated that compounds 12k (EC50 [AMPKα1γ1ß1] = 180 nM) and 13q (EC50 [AMPKα1γ1ß1] = 2 nM) displayed significant enzyme activation. Mechanism studies indicated that both compounds reduced the levels of reactive oxygen species in a rat kidney fibroblast cell line (NRK-49F) stimulated by transforming growth factor-ß and induced early apoptosis of NRK-49F cells at 10 µM. Molecular docking studies suggested that 13q exhibited critical hydrogen-bond interactions with the critical amino acid residues Lys29, Lys31, Asn111, and Asp88 at the binding site of the AMPK protein. These results enrich the structure pool of AMPK activators and provide novel lead compounds for the subsequent development of compounds with a promising therapeutic potential against DN.


Assuntos
Ativadores de Enzimas/farmacologia , Oxidiazóis/farmacologia , Pirazóis/farmacologia , Piridonas/farmacologia , Proteínas Quinases Ativadas por AMP/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Desenho de Fármacos , Ativação Enzimática/efeitos dos fármacos , Ativadores de Enzimas/síntese química , Ativadores de Enzimas/química , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Humanos , Rim/citologia , Rim/efeitos dos fármacos , Simulação de Acoplamento Molecular , Oxidiazóis/síntese química , Oxidiazóis/química , Pirazóis/síntese química , Pirazóis/química , Piridonas/síntese química , Piridonas/química , Ratos , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-Atividade
15.
Appl Environ Microbiol ; 85(10)2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-30902851

RESUMO

Crude glycerol is largely generated as the main by-product of the biodiesel industry and is unprofitable for industrial application without costly purification. The direct bioconversion of crude glycerol into 1,3-propanediol (1,3-PDO) by microorganisms is a promising alternative for effective and economic utilization. In this study, Klebsiella pneumoniae 2e was newly isolated for the conversion of crude glycerol into 1,3-PDO. Batch fermentation analysis confirmed that crude glycerol and its main impurities had slight impacts on the growth, key enzyme activity, and 1,3-PDO production of K. pneumoniae 2e. The 1,3-PDO yield from crude glycerol by K. pneumoniae 2e reached 0.64 mol 1,3-PDO/mol glycerol, which was higher than that by most reported 1,3-PDO-producing Klebsiella strains. Genomic profiling revealed that K. pneumoniae 2e possesses 30 genes involved in glycerol anaerobic metabolism and 1,3-PDO biosynthesis. Quantitative real-time PCR analysis of these genes showed that the majority of the genes encoding the key enzymes for glycerol metabolism and 1,3-PDO biosynthesis were significantly upregulated during culture in crude glycerol relative to that in pure glycerol. Further comparative genomic analysis revealed a novel glycerol uptake facilitator protein in K. pneumoniae 2e and a higher number of stress response proteins than in other Klebsiella strains. This work confirms the adaptability of a newly isolated 1,3-PDO-producing strain, K. pneumoniae 2e, to crude glycerol and provides insights into the molecular mechanisms involved in its crude glycerol tolerance, which is valuable for industrial 1,3-PDO production from crude glycerol.IMPORTANCE The rapid development of the biodiesel industry has led to tremendous crude glycerol generation. Due to the presence of complex impurities, crude glycerol has low value for industry without costly purification. Obtaining novel microorganisms capable of direct and efficient bioconversion of crude glycerol to value-added products has great economic potential for industrial application. In this work, we characterized a newly isolated strain, Klebsiella pneumoniae 2e, with the capacity to efficiently produce 1,3-propanediol (1,3-PDO) from crude glycerol and demonstrated its adaptation to crude glycerol. Our work provides insights into the molecular mechanisms of K. pneumoniae 2e adaptation to crude glycerol and the expression patterns of its genes involved in 1,3-PDO biosynthesis, which will contribute to the development of industrial 1,3-PDO production from crude glycerol.


Assuntos
Glicerol/metabolismo , Klebsiella pneumoniae/metabolismo , Propilenoglicóis/metabolismo
16.
Appl Opt ; 58(18): 5107-5114, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31503832

RESUMO

The operational reliability directly affects the practical application of optical current transformers (OCTs) in smart substations. As the key component of the OCT, the reliability of the optical current sensor (OCS) largely determines the reliability level of the OCT. This paper proposes a reliability assessment method of the OCS based on accelerated aging tests. The failure modes and failure mechanisms of the OCS are analyzed, and the concept of OCS insertion loss variation is proposed. An allowable range of insertion loss variation is selected as the failure criterion of the OCS. From the viewpoint of the OCS measurement error generated by the quantization error of the analog-to-digital converter, the allowable range of insertion loss variation is obtained. By selecting a high temperature as the accelerated thermal stress, we design the accelerated aging test scheme of the OCS and analyze the sample test data to obtain the activation energy of the OCS insertion loss failure. Based on this activation energy, the median time to failure and instantaneous failure rate curve of the OCS at normal temperature are obtained. The results indicate that the designed OCS has an expected service life of 50 years and a low instantaneous failure rate at normal temperature. This paper provides basic critical reliability analysis data for the system reliability assessment of OCTs.

17.
Appl Opt ; 57(22): 6283-6289, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30117854

RESUMO

Inhomogeneous media are affected by a physical or an electromagnetic field, where the off-diagonal elements of the Jones matrix are complex numbers with both real and imaginary parts. Inhomogeneities of the electromagnetic field result in the eigenvalue coordinate system changing along the light path. In this study, we used the unitary transformation to propose a Jones matrix of the inhomogeneous-field-induced medium with three physical or electromagnetic parameters: the medium's phase delay, induction angle, and inhomogeneous angle. This Jones matrix and the integral formulas of its three parameters are applicable to not only remarkable optical effects but also for the light propagation process of inhomogeneous-field-induced media.

18.
Med Sci Monit ; 22: 2775-8, 2016 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-27495944

RESUMO

BACKGROUND Adrenomedullin, a recently identified myokine, has an anti-inflammatory effect. Therefore, we aimed to assess the correlation of adrenomedullin concentrations with the presence and grade of severity of knee osteoarthritis (OA). MATERIAL AND METHODS We recruited 187 knee OA patients and 109 healthy subjects. The severity of OA was evaluated using the Kellgren-Lawrence grading system. RESULTS Compared with the control group, the knee OA group revealed markedly higher adrenomedullin concentrations. Serum and synovial fluid (SF) adrenomedullin concentrations increased with increased KL grades. CONCLUSIONS Serum and SF adrenomedullin concentrations show a correlation with the severity of knee OA.


Assuntos
Adrenomedulina/metabolismo , Osteoartrite do Joelho/metabolismo , Adrenomedulina/sangue , Idoso , Biomarcadores/sangue , Biomarcadores/metabolismo , Estudos de Casos e Controles , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/sangue , Osteoartrite do Joelho/patologia , Índice de Gravidade de Doença , Líquido Sinovial/metabolismo
19.
Int J Biol Macromol ; 272(Pt 1): 132842, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38830490

RESUMO

Eco-friendly and renewable sodium alginate, as a potential alternative to fossil resources, has attracted considerable attention in wastewater treatment field. Herein, we develop a SA/PEI/PEG (sodium alginate/polyethyleneimine/polyethylene glycol diglycidyl ether) adsorbent in which SA was functionalized by PEI/PEG via a facile but effective strategy of one-pot gelation of aqueous SA/PEI/PEG solution. Systematic investigations were accomplished to explore the effects of adsorbent factors on the adsorption performances of the adsorbent towards the anionic dyes CR (congo red), AB-10B (amido black-10B), and AB-25 (acid blue-25). Strikingly, the SA/PEI/PEG exhibited exceptional adsorption performance to CR (2782 mg g-1, 90.6 %), AB-10B (1369 mg g-1, 90.9 %) and AB-25 (4221 mg g-1, 92.6 %) at 30 °C, pH = 3, 200 r min-1 and oscillated 24 h, and demonstrating exceptional reusability after six cycles of adsorption-desorption cycles. Furthermore, the three kinetic, four isothermic and one thermodynamic models were used to investigate the adsorption behaviors of the adsorbent towards these dyes. The possible adsorption mechanism is suggested: Hydrogen bond interactions and electrostatic attractions between SA/PEI/PEG and the dyes primarily contribute to exceptional adsorption capacity. The SA/PEI/PEG adsorbent endowed with easy fabrication, extraordinary adsorption capacity and excellent reusability promises potential application prospects in wastewater purification industry.


Assuntos
Alginatos , Corantes , Poluentes Químicos da Água , Purificação da Água , Alginatos/química , Adsorção , Corantes/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Ânions/química , Cinética , Polietilenoglicóis/química , Concentração de Íons de Hidrogênio , Polietilenoimina/química , Termodinâmica
20.
World Neurosurg ; 184: e417-e448, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38309653

RESUMO

OBJECTIVE: The purpose of this study was to compare the efficacy of the lateral approach and posterior approach in the treatment of lumbar degenerative diseases. METHODS: Through a systematic search of relevant articles published on or before July 20, 2023, in the Embase, PubMed, and Cochrane libraries, the 2 authors independently extracted data and used the Newcastle‒Ottawa scale to evaluate the quality of the included studies. Using Stata16 software, the continuous variables were presented as the standard mean deviation, and the bipartite variables were analyzed using the pooled odds ratio with 95% confidence interval. RESULTS: A total of 13,892 articles were screened and 10,908 studies were identified after deleting duplicates, of which 41 met the criteria and were included in the meta-analysis. The meta-analysis showed that the lateral approach was superior to the posterior approach in reducing blood loss, operation time, and hospital stay. At the same time, compared with the posterior approach, the lateral approach has more advantages in the long-term Japanese Orthopaedic Association score and Oswestry Disability Index score, adjusting mid- and long-term LL and short- and long-term disc height. CONCLUSIONS: Lateral and posterior surgery have similar clinical effects in the treatment of lumbar degenerative diseases and can significantly reduce pain and improve postoperative SL. At the same time, the lateral approach has more advantages in improving long-term quality of life, reducing the long-term disability index, adjusting mid- and long-term LL and short- and long-term disc height.


Assuntos
Qualidade de Vida , Fusão Vertebral , Humanos , Estudos de Coortes , Região Lombossacral/cirurgia , Dor , Vértebras Lombares/cirurgia , Resultado do Tratamento , Estudos Retrospectivos
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