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1.
Int J Hyperthermia ; 39(1): 490-496, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35285391

RESUMO

OBJECTIVE: To investigate the efficacy of radiofrequency ablation (RFA) as a treatment option for primary hyperparathyroidism (pHPT) and risk factors for postablative eucalcemic parathyroid hormone elevation (ePTH). METHODS: This retrospective study included 51 patients with pHPT who underwent RFA. The patients were divided into the ePTH and normal PTH groups, based on the serum intact parathyroid hormone (iPTH) level one month after ablation. Serum iPTH, calcium, and phosphorus levels, and the volume reduction rates (VRR) of the parathyroid glands were compared between the groups at each follow-up point. Risk factors for ePTH at one month after ablation were examined. RESULTS: After RFA, one (2%) patient had persistent pHPT, and 50 (98%) patients were cured. The incidence rates of ePTH at 1, 3, 6, and 12 months were 48%, 30%, 20%, and 16%, respectively. Serum iPTH levels in the ePTH group were higher than those in the normal PTH group at each follow-up point (all p < 0.05), except 1 day after ablation (p > 0.05). Serum calcium and phosphorus levels, and the VRR of the glands were comparable in both groups at each follow-up point (all p > 0.05), except for calcium levels 3 days after RFA (p < 0.05). Baseline iPTH (odds ratio, 1.067; p = 0.045) and calcium (odds ratio, 3.923; p = 0.038) levels were independent risk factors for ePTH 1 month after RFA. CONCLUSIONS: RFA is safe and effective for the treatment of pHPT. Moreover, ePTH occurrence after RFA was associated with baseline iPTH and calcium levels and did not increase the risk of recurrent pHPT.


Assuntos
Hiperparatireoidismo Primário , Ablação por Radiofrequência , Cálcio , Humanos , Hiperparatireoidismo Primário/cirurgia , Hormônio Paratireóideo , Paratireoidectomia , Ablação por Radiofrequência/efeitos adversos , Estudos Retrospectivos , Fatores de Risco
2.
J Fish Dis ; 45(11): 1711-1719, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35916773

RESUMO

Nervous necrosis virus (NNV) is one of the most destructive pathogens in marine fish aquaculture and is capable of infecting more than 50 fish species worldwide, which resulted in great economic losses. Effective drugs for managing NNV infection are urgently required. Medicinal plants have been known for thousands of years and benefit of medicinal plants against pathogens in aquaculture have emerged. Nowadays, the most commonly used method for detecting virus infection and assessing antiviral drugs efficacy is reverse transcription-quantitative real-time PCR. However, the application is limited on account of high reagent costs, complex time-consuming operations and long detection time. Aptamers have been widely applied in application of pathogens or diseases diagnosis and treatments because of high specificity, strong affinity, good stability, easy synthesized and low costs. This study aimed to establish an aptamer (GBN34)-based high-throughput screening (GBN34-AHTS) model for efficient selection and evaluation of natural ingredients against NNV infection. GBN34-AHTS is an expeditious rapid method for selecting natural ingredients against NNV, which is characterized with high-speed, dram, sensitive and accurate. AHTS strategy could reduce work intensity and experimental costs and shorten the whole screening cycle of effective ingredients. AHTS should be suitable for rapid selection of effective ingredients against other viruses, which is important for improving the prevention and controlling of aquatic diseases.


Assuntos
Doenças dos Peixes , Nodaviridae , Infecções por Vírus de RNA , Animais , Antivirais/farmacologia , Antivirais/uso terapêutico , Doenças dos Peixes/diagnóstico , Doenças dos Peixes/tratamento farmacológico , Doenças dos Peixes/prevenção & controle , Nodaviridae/fisiologia , Infecções por Vírus de RNA/tratamento farmacológico , Infecções por Vírus de RNA/prevenção & controle , Infecções por Vírus de RNA/veterinária
3.
J Ultrasound Med ; 39(4): 775-784, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31675129

RESUMO

OBJECTIVES: To evaluate the performance of fetal intelligent navigation echocardiography (FINE) applied to spatiotemporal image correlation (STIC) volumes in generating 3 specific abnormal cardiac views (left ventricular outflow tract, right ventricular outflow tract, and 3-vessel and trachea) used to screen for d-transposition of the great arteries (d-TGA). METHODS: In this prospective study, 1 or more STIC volumes were obtained from the 4-chamber view in 34 second- and third-trimester fetuses with d-TGA. Each appropriate STIC volume was evaluated by STICLoop (Samsung Medison, Seoul, Korea) before applying the FINE method. One optimal volume per fetus was selected by observers. The visualization rates of the 3 specific abnormal cardiac views of d-TGA and their diagnostic elements were calculated, and the reliability between 2 observers was verified by the intraclass correlation coefficient. RESULTS: Fetal intelligent navigation echocardiography applied to STIC volume data sets of fetuses with d-TGA successfully generated the 3 specific abnormal cardiac views in the following manner for 2 observers: 75.0% (n = 21) for the left ventricular outflow tract, 89.2% (n = 25) for the right ventricular outflow tract, and 85.7% (n = 24) for the 3-vessel and trachea view. Twenty-four (85.7%) of the STIC volume data sets showed 2 or 3 of the abnormal cardiac views. The interobserver intraclass correlation coefficients between the 2 observers ranged from 0.842 to 1.000 (95% confidence interval), indicating almost perfect reliability for the 2 observers. CONCLUSIONS: In cases of d-TGA, the FINE method has a high success rate in generating 3 specific abnormal cardiac views and therefore can be performed to screen for this congenital defect.


Assuntos
Ecocardiografia/métodos , Coração Fetal/diagnóstico por imagem , Transposição dos Grandes Vasos/diagnóstico por imagem , Transposição dos Grandes Vasos/embriologia , Ultrassonografia Pré-Natal/métodos , Feminino , Coração Fetal/embriologia , Humanos , Gravidez , Estudos Prospectivos , Reprodutibilidade dos Testes
4.
Appl Environ Microbiol ; 84(13)2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29703733

RESUMO

Although some bacteria, including Chromohalobacter salexigens DSM 3043, can use glycine betaine (GB) as a sole source of carbon and energy, little information is available about the genes and their encoded proteins involved in the initial step of the GB degradation pathway. In the present study, the results of conserved domain analysis, construction of in-frame deletion mutants, and an in vivo functional complementation assay suggested that the open reading frames Csal_1004 and Csal_1005, designated bmoA and bmoB, respectively, may act as the terminal oxygenase and the ferredoxin reductase genes in a novel Rieske-type oxygenase system to convert GB to dimethylglycine in C. salexigens DSM 3043. To further verify their function, BmoA and BmoB were heterologously overexpressed in Escherichia coli, and 13C nuclear magnetic resonance analysis revealed that dimethylglycine was accumulated in E. coli BL21(DE3) expressing BmoAB or BmoA. In addition, His-tagged BmoA and BmoB were individually purified to electrophoretic homogeneity and estimated to be a homotrimer and a monomer, respectively. In vitro biochemical analysis indicated that BmoB is an NADH-dependent flavin reductase with one noncovalently bound flavin adenine dinucleotide (FAD) as its prosthetic group. In the presence of BmoB, NADH, and flavin, BmoA could aerobically degrade GB to dimethylglycine with the concomitant production of formaldehyde. BmoA exhibited strict substrate specificity for GB, and its demethylation activity was stimulated by Fe2+ Phylogenetic analysis showed that BmoA belongs to group V of the Rieske nonheme iron oxygenase (RO) family, and all the members in this group were able to use quaternary ammonium compounds as substrates.IMPORTANCE GB is widely distributed in nature. In addition to being accumulated intracellularly as a compatible solute to deal with osmotic stress, it can be utilized by many bacteria as a source of carbon and energy. However, very limited knowledge is presently available about the molecular and biochemical mechanisms for the initial step of the aerobic GB degradation pathway in bacteria. Here, we report the molecular and biochemical characterization of a novel two-component Rieske-type monooxygenase system, GB monooxygenase (BMO), which is responsible for oxidative demethylation of GB to dimethylglycine in C. salexigens DSM 3043. The results gained in this study extend our knowledge on the catalytic reaction of microbial GB degradation to dimethylglycine.


Assuntos
Betaína/metabolismo , Chromohalobacter/enzimologia , Chromohalobacter/metabolismo , Desmetilação , Oxigenases de Função Mista/metabolismo , Oxigenases/metabolismo , Proteínas de Bactérias/genética , Catálise , Chromohalobacter/genética , Chromohalobacter/crescimento & desenvolvimento , Dinitrocresóis/farmacologia , Ácido Edético/farmacologia , Escherichia coli/genética , Escherichia coli/metabolismo , Deleção de Genes , Cinética , Metais/farmacologia , Oxigenases de Função Mista/efeitos dos fármacos , Oxigenases de Função Mista/genética , Peso Molecular , Mutação , Fases de Leitura Aberta , Oxirredução , Oxirredutases/genética , Oxigenases/efeitos dos fármacos , Oxigenases/genética , Sarcosina/análogos & derivados , Alinhamento de Sequência , Análise de Sequência de Proteína , Especificidade por Substrato
5.
J Food Sci Technol ; 55(6): 2310-2317, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29892131

RESUMO

Milkfish (Chanos chanos), which is resistant to water quality changes is the fourth largest aquaculture commodity. Abandoned wastes of fish scale and bones aggravate environmental pollution. In this study, the effect of collagen peptides isolated from milkfish scales (MSCP) by pepsin-soluble collagen method on cell viability was investigated. The antioxidant, anti-inflammatory, and DNA-protective activities of MSCP were also evaluated. Results revealed that more than 95% of viable cells were retained in human keratinocytes after addition of 100 mg/mL MSCP. Measurement of DPPH· and ABTS· + radical scavenging activities and cellular reactive oxygen species revealed the high antioxidant activities of MSCP. MSCP demonstrated anti-inflammatory activities by reducing lipoxygenase activity and nitric oxide (NO·) radicals. Moreover, DNA electrophoresis assay indicated that MSCP treatment can directly protect against cyclobutane di-pyrimidine production and DNA single-strand breaks, which are harmful effects of UV radiation and H2O2. Given its antioxidant, anti-inflammatory, and DNA-protective activities, MSCP has potential applications in cosmeceuticals and supplementary health food.

6.
Nanotechnology ; 28(36): 365301, 2017 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-28684661

RESUMO

Silver nanowires (Ag NWs) are a promising material for building various sensors and devices at the nanoscale. However, the fast and precise placement of individual Ag NWs is still a challenge today. Atomic force microscopy (AFM) has been widely used to manipulate nanoparticles, yet this technology encounters many difficulties when being applied to the movement of Ag NWs as well as other soft one-dimensional (1D) materials, since the samples are easily distorted or even broken due to friction and adhesion on the substrate. In this paper, two novel manipulation strategies based on the parallel pushing method are presented. This method applies a group of short parallel pushing vectors (PPVs) to the Ag NW along its longitudinal direction. Identical and proportional vectors are respectively proposed to translate and rotate the Ag NWs with a straight-line configuration. The rotation strategy is also applied to straighten flexed Ag NWs. The finite element method simulation is introduced to analyse the behaviour of the Ag NWs as well as to optimize the parameter setting of the PPVs. Experiments are carried out to confirm the efficiency of the presented strategies. By comprehensive application of the new strategies, four Ag NWs are continuously assembled in a rectangular pattern. This study improves the controllability of the position and configuration of Ag NWs on a flat substrate. It also indicates the practicability of automatic nanofabrication using common AFMs.

7.
Med Sci Monit ; 23: 4382-4390, 2017 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-28892468

RESUMO

BACKGROUND Leukocyte telomere length (LTL) is regarded as a potential marker of biological aging. Oxidative stress plays a major role in the rate of telomeric DNA loss. The aim of this study was to explore whether the LTL was shorter in Chinese patients with premature coronary artery disease (PCAD) than in non-CAD controls and to determine the relationship between oxidative stress and LTL shortening in this population. MATERIAL AND METHODS Patients for coronary angiography were recruited. In total, 128 patients with PCAD and 128 non-CAD controls were enrolled. Samples of circulating leukocytes and plasma were collected. The mean LTL was measured using a polymerase chain reaction-based assay and expressed as the ratio of telomere repeat copies to single-copy gene (SCG) copies (T/S ratio). Reactive oxygen species (ROS) levels and total antioxidant capacity (T-AOC) were determined in plasma. RESULTS Both the T/S ratio (0.88±0.86 vs. 1.10±0.57, P=0.015) and telomere base pairs (4.97±1.37 kb vs. 5.32±0.91 kb, P=0.015) were significantly shorter in the PCAD group than in non-CAD controls. The T-AOC levels of the PCAD group were significantly lower than those of the non-CAD controls (0.482 mM [0.279, 0.603 mM]) vs. 0.778 mM [0.421, 0.924 mM], P=0.000). The ratio of T-AOC to ROS in the PCAD patients was significantly decreased compared to that of the non-CAD controls (0.1026±0. 1587 [Mm*ml/ng] vs. 0.1435±0.1946 [Mm*ml/ng], P=0.013). CONCLUSIONS The results point to a potential link between reduced LTLs in patients with PCAD and early onset of atherosclerosis. The decline in antioxidant capacity may play an important role in accelerating the attrition of telomeres in PCAD patients.


Assuntos
Doença da Artéria Coronariana/genética , Estresse Oxidativo/genética , Telômero/fisiologia , Adulto , Idoso , Povo Asiático/genética , Aterosclerose/genética , Aterosclerose/fisiopatologia , Biomarcadores/sangue , China , Doença da Artéria Coronariana/fisiopatologia , Feminino , Humanos , Leucócitos/fisiologia , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/sangue , Espécies Reativas de Oxigênio/metabolismo , Telômero/genética , Homeostase do Telômero/genética , Homeostase do Telômero/fisiologia
8.
Ecotoxicol Environ Saf ; 138: 56-63, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28011421

RESUMO

Two metal-resistant Bacillus megaterium H3 and Neorhizobium huautlense T1-17 were investigated for their immobilization of Cd in solution and tissue Cd accumulation of rice (Oryza sativa wuyun-23) in the Cd-contaminated soil. Strains H3 and T1-17 decreased 79-96% of water-soluble Cd in solution and increased grain biomass in the high Cd-contaminated soil. Inoculation with H3 and T1-17 significantly decreased the root (ranging from 25% to 58%), above-ground tissue (ranging from 13% to 34%), and polished rice (ranging from 45% to 72%) Cd contents as well as Cd bioconcentration factor of the rice compared to the controls. Furthermore, H3 and T1-17 significantly reduced the exchangeable Cd content of the rhizosphere soils compared with the controls. Notably, strain T1-17 had significantly higher ability to reduce Cd bioconcentration factor and polished rice Cd uptake than strain H3. The results demonstrated that H3 and T1-17 decreased the tissue (especially polished rice) Cd uptake by decreasing Cd availability in soil and Cd bioconcentration factor and the effect on the reduced polished rice Cd uptake was dependent on the strains. The results may provide an effective synergistic bioremediation of Cd-contaminated soils in the bacteria and rice plants and bacterial-assisted safe production of rice in Cd-contaminated soils.


Assuntos
Bacillus megaterium/metabolismo , Cádmio/metabolismo , Metais Pesados/metabolismo , Oryza/metabolismo , Rhizobium/metabolismo , Poluentes do Solo/metabolismo , Biodegradação Ambiental , Biomassa , Cádmio/análise , Grão Comestível/química , Metais Pesados/análise , Raízes de Plantas/metabolismo , Rizosfera , Solo/química , Poluentes do Solo/análise
9.
PLoS Pathog ; 9(1): e1003132, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23341770

RESUMO

Rabbit hemorrhagic disease, first described in China in 1984, causes hemorrhagic necrosis of the liver. Its etiological agent, rabbit hemorrhagic disease virus (RHDV), belongs to the Lagovirus genus in the family Caliciviridae. The detailed molecular structure of any lagovirus capsid has yet to be determined. Here, we report a cryo-electron microscopic (cryoEM) reconstruction of wild-type RHDV at 6.5 Å resolution and the crystal structures of the shell (S) and protruding (P) domains of its major capsid protein, VP60, each at 2.0 Å resolution. From these data we built a complete atomic model of the RHDV capsid. VP60 has a conserved S domain and a specific P2 sub-domain that differs from those found in other caliciviruses. As seen in the shell portion of the RHDV cryoEM map, which was resolved to ~5.5 Å, the N-terminal arm domain of VP60 folds back onto its cognate S domain. Sequence alignments of VP60 from six groups of RHDV isolates revealed seven regions of high variation that could be mapped onto the surface of the P2 sub-domain and suggested three putative pockets might be responsible for binding to histo-blood group antigens. A flexible loop in one of these regions was shown to interact with rabbit tissue cells and contains an important epitope for anti-RHDV antibody production. Our study provides a reliable, pseudo-atomic model of a Lagovirus and suggests a new candidate for an efficient vaccine that can be used to protect rabbits from RHDV infection.


Assuntos
Capsídeo/ultraestrutura , Vírus da Doença Hemorrágica de Coelhos/ultraestrutura , Proteínas Estruturais Virais/ultraestrutura , Sequência de Aminoácidos , Animais , Infecções por Caliciviridae/veterinária , Infecções por Caliciviridae/virologia , Proteínas do Capsídeo , Microscopia Crioeletrônica , Cristalografia por Raios X , Modelos Moleculares , Ligação Proteica , Estrutura Terciária de Proteína , Coelhos/virologia , Alinhamento de Sequência , Proteínas Estruturais Virais/química
10.
J Org Chem ; 80(20): 10380-5, 2015 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-26402054

RESUMO

Under catalysis of 10 mol % of Et3N, the [3 + 2] cycloaddition of barbiturate-based olefins with 3-isothiocyanato oxindoles underwent smoothly and afforded the desired dispirobarbiturates in up to 99% yield with up to 99:1 dr. The relative configuration of the dispirobarbiturates was unambiguously determined by X-ray single-crystal structure analysis. The reaction mechanism was proposed to shed light on the diastereoselective formation of the dispirobarbiturates.

11.
Immunopharmacol Immunotoxicol ; 37(6): 513-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26525510

RESUMO

Myricetin, a common dietary flavonoid, is widely distributed in fruits and vegetables. It is known to be a food supplement contributing to human health because of its immune modulatory function, and its antioxidation, antitumor, and anti-inflammatory properties. In the present study, myricetin was shown to directly inhibit cathepsin K activity, a highly potent collagenase, which is the predominant papain-like cysteine protease expressed in osteoclasts and synovial fibroblasts. It was shown that the IC50 of myricetin for the recombinant human cathepsin was 585.3 µmol/L. Also, myricetin proved to have positive effects in murine collagen-induced arthritis (CIA). Mice suffering from CIA received a daily dose of myricetin (25 mg/kg, per os). During the study, the clinical severity of the CIA and the histopathology were evaluated. Biomarkers related to the histological evaluation of cartilage degradation, namely deoxypyridinoline, cartilage oligomeric matrix protein and C-terminal telopeptide degradation product of type I collagen (CTX-I), were analyzed. Myricetin treatment reduced the levels of biomarkers indicative of cartilage degradation (p < 0.05) and ameliorated the symptoms of CIA in mice at the clinical level (p < 0.01). As the inhibitory effect of myricetin on cathepsin K activity induced beneficial effects on CIA in mice, further investigation of therapeutic interventions with myricetin in other mammals or in human rheumatoid arthritis is recommended.


Assuntos
Artrite Experimental/tratamento farmacológico , Artrite Experimental/enzimologia , Catepsina K/antagonistas & inibidores , Catepsina K/metabolismo , Flavonoides/uso terapêutico , Animais , Artrite Experimental/patologia , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Feminino , Flavonoides/farmacologia , Camundongos , Camundongos Endogâmicos DBA
12.
Neurosignals ; 22(1): 52-63, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25095809

RESUMO

Cycloastragenol (CAG) is an aglycone of astragaloside IV. It was first identified when screening Astragalus membranaceus extracts for active ingredients with antiaging properties. The present study demonstrates that CAG stimulates telomerase activity and cell proliferation in human neonatal keratinocytes. In particular, CAG promotes scratch wound closure of human neonatal keratinocyte monolayers in vitro. The distinct telomerase-activating property of CAG prompted evaluation of its potential application in the treatment of neurological disorders. Accordingly, CAG induced telomerase activity and cAMP response element binding (CREB) activation in PC12 cells and primary neurons. Blockade of CREB expression in neuronal cells by RNA interference reduced basal telomerase activity, and CAG was no longer efficacious in increasing telomerase activity. CAG treatment not only induced the expression of bcl2, a CREB-regulated gene, but also the expression of telomerase reverse transcriptase in primary cortical neurons. Interestingly, oral administration of CAG for 7 days attenuated depression-like behavior in experimental mice. In conclusion, CAG stimulates telomerase activity in human neonatal keratinocytes and rat neuronal cells, and induces CREB activation followed by tert and bcl2 expression. Furthermore, CAG may have a novel therapeutic role in depression.


Assuntos
Depressão/tratamento farmacológico , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Sapogeninas/administração & dosagem , Telomerase/metabolismo , Animais , Antidepressivos/administração & dosagem , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Humanos , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Camundongos , Fator de Crescimento Neural/metabolismo , Células PC12 , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Sapogeninas/síntese química
13.
Protein Expr Purif ; 104: 50-6, 2014 12.
Artigo em Inglês | MEDLINE | ID: mdl-25224799

RESUMO

Mycobacterium tuberculosis possesses an unusually high number of genes involved in the metabolism of lipids. Driven by a newly described esterase motif SXXK in the amino acid sequence and a predicted signal peptide, the gene rv3036c from M. tuberculosis was cloned and characterized biochemically. Rv3036c efficiently hydrolyzes soluble p-nitrophenyl esters but not emulsified lipid. The highest activity of this enzyme was observed when p-nitrophenyl acetate (C2) was used as the substrate. Based on the activities, Rv3036c was classified as a nonlipolytic hydrolase. The results of immunoreactivity studies on the subcellular mycobacterial fractions suggested that the enzyme was present in the cell wall and cell membrane in mycobacteria. In summary, Rv3036c was characterized as a novel cell wall-anchored esterase from M. tuberculosis.


Assuntos
Esterases/isolamento & purificação , Mycobacterium tuberculosis/enzimologia , Sequência de Aminoácidos , Ativação Enzimática , Escherichia coli , Esterases/biossíntese , Nitrofenóis/metabolismo , Sinais Direcionadores de Proteínas
14.
Int J Biol Macromol ; 260(Pt 1): 129499, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38262829

RESUMO

Chondroitin sulfate (CS) was extracted and purified from shark cartilage, and its interaction with bovine serum albumin (BSA) were studied. The content of chondroitin sulfate in shark cartilage was 29.97 % using the 1,9-dimethyl-methylene blue method. The molecular weight of CS was determined to be 62.464 kDa by high-performance gel permeation chromatography. UV and FT-IR spectroscopy identified the characteristics of CS and its functional group information. NMR spectroscopy and disaccharide derivatization revealed that CS was predominantly composed of disulfated disaccharides, specifically ΔDi4,6S. Fluorescence quenching experiments indicated that the interaction between CS and BSA exhibited static quenching, with a binding site number of 1. The binding process was primarily mediated by van der Waals forces and hydrogen bonds. Furthermore, synchronous and 3D fluorescence spectroscopy demonstrated that CS had minimal impact on the polarity and hydrophobicity of the microenvironment surrounding Tyr and Trp residues. UV-vis absorption and circular dichroism (CD) spectroscopy demonstrated the altered structure of BSA. The molecular docking analysis revealed that CS formed hydrogen bonds and salt bridges with BSA, predominantly binding to the IIA substructure domain of BSA. Investigating the interaction between CS and BSA holds the potential for enhancing its applications in drug delivery and tissue engineering endeavors.


Assuntos
Soroalbumina Bovina , Tubarões , Animais , Simulação de Acoplamento Molecular , Soroalbumina Bovina/química , Sulfatos de Condroitina/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , Espectrometria de Fluorescência/métodos , Sítios de Ligação , Cartilagem/metabolismo , Ligação Proteica , Dicroísmo Circular
15.
Nat Commun ; 14(1): 6991, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37914684

RESUMO

Follicle-stimulating hormone (FSH) is involved in mammalian reproduction via binding to FSH receptor (FSHR). However, several studies have found that FSH and FSHR play important roles in extragonadal tissue. Here, we identified the expression of FSHR in human and mouse pancreatic islet ß-cells. Blocking FSH signaling by Fshr knock-out led to impaired glucose tolerance owing to decreased insulin secretion, while high FSH levels caused insufficient insulin secretion as well. In vitro, we found that FSH orchestrated glucose-stimulated insulin secretion (GSIS) in a bell curve manner. Mechanistically, FSH primarily activates Gαs via FSHR, promoting the cAMP/protein kinase A (PKA) and calcium pathways to stimulate GSIS, whereas high FSH levels could activate Gαi to inhibit the cAMP/PKA pathway and the amplified effect on GSIS. Our results reveal the role of FSH in regulating pancreatic islet insulin secretion and provide avenues for future clinical investigation and therapeutic strategies for postmenopausal diabetes.


Assuntos
Hormônio Foliculoestimulante , Ilhotas Pancreáticas , Camundongos , Animais , Humanos , Hormônio Foliculoestimulante/farmacologia , Hormônio Foliculoestimulante/metabolismo , Secreção de Insulina , Glucose/farmacologia , Glucose/metabolismo , Receptores do FSH/genética , Receptores do FSH/metabolismo , Ilhotas Pancreáticas/metabolismo , Transdução de Sinais , Insulina/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Mamíferos/metabolismo
16.
Cryobiology ; 62(2): 91-9, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21232534

RESUMO

Many ectotherms organisms produce antifreeze proteins (AFPs) which inhibit the growth of ice by binding to the surface of ice crystals. In this study, a novel antifreeze protein gene from the desert beetle Anatolica polita (named as Apafp752) was expressed in a high level in Escherichia coli strain BL21 (DE3). An approximately 30kDa fusion protein thioredoxin (Trx)-ApAFP752 was purified through Ni-NTA affinity chromatography and gel filtration chromatography. The activity of the purified fusion protein Trx-ApAFP752 was analyzed by thermal hysteresis activity (THA) and cryoprotection assay. The results suggested that Trx-ApAFP752 conferred freeze resistance on bacterium in a concentration- and time-dependent manner and the cryoprotective effect increased under alkaline conditions. Circular Dichroism (CD) spectrum analysis showed that the recombinant protein of ApAFP752 possessing ß-sheet as the main structure was stable under a wide range of pH from 2.0 to 11.0 and thermal stability below 50°C. The predicted 3D structure showed that Trx-ApAFP752 could form a ß-helix structure on the antifreeze protein part, which placed most of the Thr in a regular array on one side of the protein to form a putative ice-binding surface.


Assuntos
Proteínas Anticongelantes/química , Dicroísmo Circular/métodos , Besouros , Crioprotetores/química , Proteínas de Insetos/química , Sequência de Aminoácidos , Animais , Proteínas Anticongelantes/isolamento & purificação , Clonagem Molecular/métodos , Crioprotetores/isolamento & purificação , Escherichia coli/metabolismo , Concentração de Íons de Hidrogênio , Gelo , Proteínas de Insetos/isolamento & purificação , Modelos Moleculares , Dados de Sequência Molecular , Ligação Proteica , Estrutura Secundária de Proteína , Proteínas Recombinantes de Fusão/química , Temperatura , Tiorredoxinas/química
17.
Zhonghua Yi Xue Za Zhi ; 91(28): 1987-91, 2011 Jul 26.
Artigo em Zh | MEDLINE | ID: mdl-22093896

RESUMO

OBJECTIVE: To investigate the effects of soy isoflavones (SI) on the expression of estrogen receptor-α (ER-α) in senile rat ovaries and ovarian granulosa cell cultured in vitro treated with genistein, a major active component of SI. METHODS: The animal model of perimenopause rats was established by unforced aging. The animals were treated by intragastric administration (ig) with low (50 mg/kg), middle (158 mg/kg) and high (500 mg/kg) dose of SI for 8 weeks. The expressions of ER-α mRNA and protein were detected by reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry respectively. The granulosa cells of rat ovaries were isolated and administered with genistein (0, 0.1, 1, 5, 10, 100 µmol/L) for 48 h and the expression levels of ER-α mRNA detected by RT-PCR. RESULTS: The ER-α mRNA expression levels of the low, middle and high dose groups of SI (0.207 ± 0.014, 0.316 ± 0.073 and 0.402 ± 0.170 respectively) were higher than those of the model group (0.671 ± 0.170) (all P < 0.01). The expression levels of ER-α protein for the low, middle and high dose groups of SI (7.35 ± 4.90, 13.90 ± 5.12 and 23.79 ± 10.31 respectively) were higher than those of the model group (2.74 ± 0.09) (all P < 0.01). The expression levels of ER-α mRNA in granulosa cells treated with 1, 5, 10 µmol/L genistein for 48 h were 0.927 ± 0.232, 1.067 ± 0.154, 1.118 ± 0.126 respectively (all P < 0.01). They were higher than those of the control group (0.671 ± 0.170). But the expression levels of 100 µmol/L genistein group were lower than those of the control group (P < 0.05). CONCLUSION: Soy isoflavones can up-regulate the expressions of ER-α mRNA and protein in senile rat ovaries. As a major active component of soy isoflavones, genistein can regulate the expressions ER-α mRNA in granulosa cells of rat ovaries. Such an effect is concentration-dependent. And 1-10 µmol/L genistein may up-regulate the expression of ER-α mRNA.


Assuntos
Receptor alfa de Estrogênio/metabolismo , Genisteína/farmacologia , Isoflavonas/farmacologia , Ovário/efeitos dos fármacos , Ovário/metabolismo , Animais , Feminino , Ratos , Ratos Wistar , Glycine max/química
18.
Bioresour Bioprocess ; 8(1): 124, 2021 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38650281

RESUMO

BACKGROUND: In the last decades, replicating expression vectors based on plant geminivirus have been widely used for enhancing the efficiency of plant transient expression. By using the replicating expression vector derived from bean yellow dwarf virus and green fluorescent protein as a reporter, we investigated the effects of α-naphthalene acetic acid, gibberellins3, and 6-benzyladenine, as three common plant growth regulators, on the plant biomass and efficiency of transient expression during the process of transient expression in Nicotiana benthamiana L. leaves. RESULTS: With the increase of the concentration of α-naphthalene acetic acid, gibberellins3, and 6-benzyladenine (from 0.1 to 1.6 mg/L), the fresh weight, dry weight, and leaf area of the seedlings increased first and then returned to the levels similar to the controls (without chemical treatment). The treatment with α-naphthalene acetic acid at 0.2 and 0.4 mg/L can enhance the level of transient expression of green fluorescent protein, which peaked at 0.4 mg/L α-naphthalene acetic acid and was increased about by 19%, compared to the controls. Gibberellins3 at 0.1-0.4 mg/L can enhance the level of transient expression of green fluorescent protein, which peaked at 0.2 mg/L gibberellins3 and was increased by 25%. However, the application of 6-benzyladenine led to decrease in the level of transient expression of green fluorescent protein. CONCLUSIONS: The appropriate plant growth regulators at moderate concentration could be beneficial to the expression of foreign genes from the Agrobacterium-mediated transient expression system in plants. Thus, appropriate plant growth regulators could be considered as exogenous components that are applied for the production of recombinant protein by plant-based transient expression systems.

19.
Mol Cell Endocrinol ; 529: 111264, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33811969

RESUMO

Over the past four decades, the global prevalence of obesity has increased rapidly in all age ranges. Emerging evidence suggests that paternal lifestyle and environmental exposure have a crucial role in the health of offspring. Therefore, the current study investigated the impact of paternal obesity on the metabolic profile of offspring in a male mouse model of obesity. Female offspring of obese fathers fed a high-fat diet (HFD) (60% kcal fat) showed hyperglycemia because of enhanced gluconeogenesis and elevated expression of phosphoenolpyruvate carboxykinase (PEPCK), which is a key enzyme involved in the regulation of gluconeogenesis. Methylation of the Igf2/H19 imprinting control region (ICR) was dysregulated in the liver of offspring, and the sperm, of HFD fathers, suggesting that epigenetic changes in germ cells contribute to this father-offspring transmission. In addition, we explored whether H19 might regulate hepatic gluconeogenesis. Our results showed that overexpression of H19 in Hepa1-6 cells enhanced the expression of PEPCK and gluconeogenesis by promoting nuclear retention of forkhead box O1 (FOXO1), which is involved in the transcriptional regulation of Pepck. Thus, the current study suggests that paternal exposure to HFD impairs the gluconeogenesis of offspring via altered Igf2/H19 DNA methylation.


Assuntos
Epigênese Genética , Hiperglicemia/genética , Fator de Crescimento Insulin-Like II/genética , Obesidade/genética , Fosfoenolpiruvato Carboxiquinase (ATP)/genética , RNA Longo não Codificante/genética , Animais , Linhagem Celular , Metilação de DNA , Dieta Hiperlipídica/efeitos adversos , Feminino , Proteína Forkhead Box O1/genética , Proteína Forkhead Box O1/metabolismo , Impressão Genômica , Gluconeogênese/genética , Hepatócitos/metabolismo , Hepatócitos/patologia , Hiperglicemia/etiologia , Hiperglicemia/metabolismo , Hiperglicemia/patologia , Padrões de Herança , Fator de Crescimento Insulin-Like II/metabolismo , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/etiologia , Obesidade/metabolismo , Obesidade/patologia , Fosfoenolpiruvato Carboxiquinase (ATP)/metabolismo , Processamento de Proteína Pós-Traducional , RNA Longo não Codificante/metabolismo , Espermatozoides/metabolismo
20.
Nat Struct Mol Biol ; 12(11): 980-6, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16228002

RESUMO

Coronavirus replication and transcription machinery involves multiple virus-encoded nonstructural proteins (nsp). We report the crystal structure of the hexadecameric nsp7-nsp8 supercomplex from the severe acute respiratory syndrome coronavirus at 2.4-angstroms resolution. nsp8 has a novel 'golf-club' fold with two conformations. The supercomplex is a unique hollow, cylinder-like structure assembled from eight copies of nsp8 and held tightly together by eight copies of nsp7. With an internal diameter of approximately 30 angstroms, the central channel has dimensions and positive electrostatic properties favorable for nucleic acid binding, implying that its role is to confer processivity on RNA-dependent RNA polymerase.


Assuntos
Modelos Moleculares , Complexos Multiproteicos/química , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/genética , Transcrição Gênica/genética , Proteínas não Estruturais Virais/química , Replicação Viral/fisiologia , Sequência de Aminoácidos , Sequência de Bases , Cristalização , Primers do DNA , Ensaio de Desvio de Mobilidade Eletroforética , Microscopia Eletrônica , Dados de Sequência Molecular , Complexos Multiproteicos/metabolismo , Complexos Multiproteicos/ultraestrutura , RNA Polimerase Dependente de RNA/metabolismo , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/fisiologia , Análise de Sequência de DNA , Relação Estrutura-Atividade , Proteínas não Estruturais Virais/metabolismo , Proteínas não Estruturais Virais/ultraestrutura , Replicação Viral/genética
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