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1.
Front Pharmacol ; 14: 1144419, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36959861

RESUMO

Background: Patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI) therapy may experience further damage to the vascular endothelium, leading to increased inflammatory response and in-stent thrombosis. In many clinical studies, sodium tanshinone IIA sulfonate injection (STS) has been found to reduce inflammatory factors and enhance vascular endothelial function in patients with ACS while improving the prognosis of PCI. However, to date, there has been no systematic review assessing the effectiveness and safety of STS on inflammatory factors and vascular endothelial function. Purpose: The aim of this study is to systematically review the effects of STS on inflammatory factors and endothelial function in patients with ACS treated with PCI. Methods: Until October 2022, eight literature databases and two clinical trial registries were searched for randomized controlled trials (RCTs) investigating STS treatment for ACS patients undergoing PCI. The quality of the included studies was assessed using the Cochrane Risk Assessment Tool 2.0. Meta-analysis was performed using RevMan 5.4 software. Results: Seventeen trials met the eligibility criteria, including 1,802 ACS patients undergoing PCI. The meta-analysis showed that STS significantly reduced high-sensitivity C-reactive protein (hs-CRP) levels (mean difference [MD = -2.35, 95% CI (-3.84, -0.86), p = 0.002], tumor necrosis factor-alpha (TNF-α) levels (standard mean difference [SMD = -3.29, 95%CI (-5.15, -1.42), p = 0,006], matrix metalloproteinase-9 (MMP-9) levels [MD = -16.24, 95%CI (-17.24, -15.24), p < 0.00001], and lipid peroxidation (LPO) levels [MD = -2.32, 95%CI (-2.70, -1.93), p < 0.00001], and increased superoxide dismutase (SOD) levels [SMD = 1.46, 95%CI (0.43, 2.49), p = 0,006] in patients with ACS. In addition, STS significantly decreased the incidence of major adverse cardiovascular events (relative risk = 0.54, 95%CI [0.44, 0.66], p < 0.00001). The quality of evidence for the outcomes was assessed to be very low to medium. Conclusion: STS can safely and effectively reduce the levels of hs-CRP, TNF-α, MMP-9, and LPO and increase the level of SOD in patients with ACS treated with PCI. It can also reduce the incidence of adverse cardiovascular events. However, these findings require careful consideration due to the small number of included studies, high risk of bias, and low to moderate evidence. In the future, more large-scale and high-quality RCTs will be needed as evidence in clinical practice.

2.
3 Biotech ; 12(1): 21, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34956814

RESUMO

Antibody-based drugs can be highly toxic, because they target normal tissue as well as tumor tissue. The pH value of the extracellular microenvironments around tumor tissues is lower than that of normal tissues. Therefore, antibodies that engage in pH-dependent binding at slightly acidic pH are crucial for improving the safety of antibody-based drugs. Thus, we implemented a stepwise mutagenesis approach to engineering pH-dependent antibodies capable of selective binding in the acidic microenvironment in this study. The first step involved single-residue histidine scanning mutagenesis of the antibody's complementarity-determining regions to prescreen for pH-dependent mutants and identify ionizable sensitive hot-spot residues that could be substituted by acidic amino acids to obtain pH-dependent antibodies. The second step involved single-acidic amino acid residue substitutions of the identified residues and the assessment of pH-dependent binding. We identified six ionizable sensitive hot-spot residues using single-histidine scanning mutagenesis. Nine pH-dependent antibodies were isolated using single-acidic amino acid residue mutagenesis at the six hot-spot residue positions. Relative to wild-type anti-CEA chimera antibody, the binding selectivity of the best performing mutant was improved by approximately 32-fold according to ELISA and by tenfold according to FACS assay. The mutant had a high affinity in the pH range of 5.5-6.0. This study supports the development of pH-dependent protein switches and increases our understanding of the role of ionizable residues in protein interfaces. The stepwise mutagenesis approach is rapid, general, and robust and is expected to produce pH-sensitive protein affinity reagents for various applications.

3.
Carbohydr Polym ; 229: 115528, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31826422

RESUMO

Carbohydrate sequences are important for various biological processes. It has recently been estimated to have 100,000-500,000 carbohydrate structures in mammalian glycome. However, the peripheral carbohydrate determinants on N- and O-glycoproteins, glycolipids, polysaccharides and secreted free sugars are limited in numbers. Among these blood-group-related antigens the ABO(H)- and Lewis-types are particularly important. Negative-ion MS/MS has been successfully used in assignment of these epitopes on free reducing sugars but cannot be applied to reduced sugars, e.g. O-glycans typically released from mucins as alditols, or in positive-ion detection of either reducing or reduced oligosaccharides. In the present study, we investigate the fragmentation features of permethylated reducing and reduced sugars under positive-ion conditions of multi-stage MALDI-MS, and propose the concept of epitope ion and epitope spectrum for determination of peripheral blood-group related epitopes on secreted human milk oligosaccharides and N-glycans as reducing sugars and O-glycans as reduced alditols in conjunction with MALDI-MS glycan profiling.


Assuntos
Epitopos/análise , Glicoproteínas/química , Oligossacarídeos/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Sistema ABO de Grupos Sanguíneos/química , Sistema ABO de Grupos Sanguíneos/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Mucosa Gástrica/metabolismo , Humanos , Íons/química , Antígenos do Grupo Sanguíneo de Lewis/química , Antígenos do Grupo Sanguíneo de Lewis/metabolismo , Leite Humano/química , Leite Humano/metabolismo , Mucinas/química , Mucinas/metabolismo , Álcoois Açúcares/química , Suínos
4.
Biochem Biophys Res Commun ; 520(1): 8-13, 2019 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-31554601

RESUMO

Glycosylation is one of the most common post-translational modifications which diversifies the structure and function of glycoproteins like immunoglobulin G (IgG). The effector function of IgG depends on N-glycan patterns located in the crystalline fragment (Fc). Fc gamma receptor (FcγR)-binding affinity is one of the most important effector functions in IgG, and it varies with different IgG isotypes. Murine IgG1 (mIgG1) triggers various immune effector functions via FcγRs, however, how N-glycans of mIgG1 impact interactions between mIgG1s and murine FcγRs remains largely unknown. Here, we generated mIgG1s with different N-glycan patterns by adding different types of N-glycan processing enzyme inhibitors to the hybridoma culture media, before comparing their FcγR-binding affinity using enzyme-linked immunosorbent assay (ELISA) analysis. We showed that N-glycans critically affect mIgG1 affinity to FcγRs. The removal of N-glycans nearly completely abolished mIgG1-FcγR binding. In comparison, when N-glycans are present, decreasing fucosylation levels enhanced the FcγR-binding affinity regardless of the types of N-glycans. Furthermore, high-mannose type and hybrid type N-glycans reduced FcγR-binding affinity, compared to complex type N-glycans. In conclusion, our findings clearly demonstrate that FcγR-binding affinity of mIgG1 is under the control of glycosylation. Importantly, we found that both the levels of specific glycosylation as well as the types of N-glycans affect FcγR-binding affinity. Together, these insights should greatly expand our understanding of N-glycans function in general, and assist in manipulating host immune responses by controlling antibody N-glycan patterns, which is important for designing therapeutic antibodies with improved characteristics.


Assuntos
Imunoglobulinas/metabolismo , Oligossacarídeos/metabolismo , Receptores de IgG/metabolismo , Animais , Sítios de Ligação , Linhagem Celular Tumoral , Imunoglobulinas/química , Imunoglobulinas/genética , Camundongos , Oligossacarídeos/análise , Receptores de IgG/química
5.
Anal Chim Acta ; 1071: 25-35, 2019 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-31128752

RESUMO

Mass spectrometry (MS) has become the primary method for high-sensitivity structural determination of oligosaccharides. Fragmentation in the negative-ion MS can provide a wealth of structural information and these can be used for sequence determination. However, although negative-ion MS of neutral oligosaccharide using the deprotonated molecule [M-H]- as the precursor has been very successful for electrospray ionization (ESI), it has only limited success for matrix-assisted laser desorption/ionization (MALDI). In the present study, the features of negative-ion MALDI primary spectra were investigated in detail and the product-ion spectra using [M-H]- and [M+Cl]- as the precursors were carefully compared. The formation of [M-H]- was the main difficulty for MALDI while [M+Cl]- was proved to be useful as alternative precursor anion for MALDI-MS/MS to produce similar fragmentation for sequencing of neutral oligosaccharides. N-(1-naphthyl)ethylenediamine dihydrochloride was then used as both the matrix and the Cl- dopant to evaluate the extent of structural information that can be obtained by negative-ion fragmentation from [M+Cl]- using laser-induced dissociation (LID)-MS/MS for linkage assignment of gluco-oligosaccharides and for typing of blood-group ABO(H) and Lewis antigens on either type 1 or type 2 backbone-chains.


Assuntos
Sistema ABO de Grupos Sanguíneos/análise , Glucanos/análise , Antígenos do Grupo Sanguíneo de Lewis/análise , Oligossacarídeos/análise , Sistema ABO de Grupos Sanguíneos/química , Tipagem e Reações Cruzadas Sanguíneas/métodos , Sequência de Carboidratos , Glucanos/química , Antígenos do Grupo Sanguíneo de Lewis/química , Oligossacarídeos/química , Análise de Sequência , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Espectrometria de Massas em Tandem/métodos
6.
Artigo em Chinês | MEDLINE | ID: mdl-27062859

RESUMO

OBJECTIVE: To conclude the revision reason of unicompartmental knee arthroplasty (UKA) using computer-assisted technology so as to provide reference for reducing the revision incidence and improving the level of surgical technique and rehabilitation. METHODS: The relevant literature on analyzing revision reason of UKA using computer-assisted technology in recent years was extensively reviewed. RESULTS: The revision reasons by computer-assisted technology are fracture of the medial tibial plateau, progressive osteoarthritis of reserved compartment, dislocation of mobile bearing, prosthesis loosening, polyethylene wear, and unexplained persistent pain. CONCLUSION: Computer-assisted technology can be used to analyze the revision reason of UKA and guide the best operating method and rehabilitation scheme by simulating the operative process and knee joint activities.


Assuntos
Artroplastia do Joelho/métodos , Articulação do Joelho/cirurgia , Prótese do Joelho , Osteoartrite do Joelho/cirurgia , Falha de Prótese/etiologia , Cirurgia Assistida por Computador/tendências , Artroplastia do Joelho/efeitos adversos , Humanos , Polietileno , Falha de Prótese/efeitos adversos , Reoperação , Software , Tíbia , Resultado do Tratamento
7.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 29(10): 1208-13, 2015 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-26749725

RESUMO

OBJECTIVE: To compare the effectiveness of single-bundle and double-bundle anterior cruciate ligament (ACL) reconstruction by two methods. METHODS: Qualified for the selective standard, 120 patients with ACL injury between May 2010 and April 2013 were divided into 4 groups: double-bundle reconstruction was performed by the conventional procedure in 30 cases (group A); anatomic double-bundle reconstruction was performed in the original ACL residual footprints in 30 cases (group B); single-bundle reconstruction was performed by the conventional procedure in 30 cases (group C); and anatomic single-bundle reconstruction was performed in the original ACL residual footprints in 30 cases (group D). There was no significant difference in gender, age, disease duration, pathogenesis, injury side, Lysholm scores, International Knee Documentation Committee (IKDC) ratings, Lachman test, anterior drawer test, and pivot shift test among groups (P > 0.05). The impingement between the ACL implants and intercondylar notch was evaluated with postoperative immediate MRI scan and the three-dimensional digital model. Lachman test, anterior drawer test, and pivot shift test results, Lysholm scores, and IKDC ratings were used to compare the effectiveness among groups after operation. RESULTS: Three-dimensional digital model after operation showed impingement in 11 cases (36.7%) of group A, 1 case (3.3%) of group B, 9 cases (30.0%) of group C, and no impingement in group D. The impingement rates of groups A and C were significantly higher than that of groups B and D (P < 0.05), but no significant difference was found between groups A and C, and between groups B and D (P > 0.05. All incisions healed by first intention, and no early complication was found. The patients were followed up 24-30 months (mean, 26 months). Lysholm scores, Lachman test, anterior drawer test, and pivot shift test results at 24 months after operation were significantly better than preoperative ones in 4 groups (P < 0.05), but no significant difference was shown among groups (P > 0.05). The IKDC ratings of groups B and D were significantly better than that of groups A and C (P < 0.05); but there was no significant difference between groups A and C, and between groups B and D (P > 0.05). CONCLUSION: Compared with the conventional procedure, the individual anatomic single- and double-bundle reconstruction in the original ACL residual footprints has decreased impingement rate and increased IKDC rating.


Assuntos
Reconstrução do Ligamento Cruzado Anterior/métodos , Ligamento Cruzado Anterior/cirurgia , Fáscia , Humanos , Traumatismos do Joelho , Articulação do Joelho , Imageamento por Ressonância Magnética , Período Pós-Operatório , Lesões dos Tecidos Moles , Resultado do Tratamento
8.
Artigo em Chinês | MEDLINE | ID: mdl-26750019

RESUMO

OBJECTIVE: To review the research progress of tissue engineered scaffolds and stromal-derived factor 1 (SDF-1) composite graft. METHODS: The recent papers about SDF-1 with different kinds of tissue engineered scaffolds were reviewed and analyzed. The primary mechanism of SDF-1 homing function for stem cells was retrospected. The results of different kinds of tissue engineered scaffolds carrying SDF-1 for repairing the injured tissues and organs were reviewed. RESULTS: It is shown that SDF-1 combined with tissue engineered scaffolds will play a role of multipotent stem cells chemotaxis, however, the exact chemotaxis mechanism has not been fully understood. It still needs more researches of SDF-1 effects in vivo. CONCLUSION: Although some research progress has been made in regeneration in situ of tissue engineered scaffolds combined with SDF-1, it will need to further study on the mechanism of chemotactic functions of SDF-1 and its influence on proliferation and differentiation of cells.


Assuntos
Quimiocina CXCL12/metabolismo , Engenharia Tecidual/métodos , Engenharia Tecidual/tendências , Alicerces Teciduais , Diferenciação Celular , Quimiotaxia , Humanos , Regeneração , Células-Tronco , Cicatrização
9.
Colloids Surf B Biointerfaces ; 95: 247-53, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22494668

RESUMO

We have successfully synthesized GSH and TGA co-capped CdTe quantum dots (QDs) with good biological compatibility and high fluorescence intensity. The effects of different reaction time, temperature, pH value, ligand concentration and the molar ratio of GSH/TGA were carefully investigated to optimize the synthesis condition. The optical properties of as-prepared CdTe QDs were studied by UV-visible absorption spectrum and fluorescence spectrum, meanwhile their structure and morphology were characterized using transmission electron microscope (TEM), Fourier transform infrared spectra (FT-IR) and X-ray powder diffraction (XRD). Compared with the CdTe QDs that are single-capped with either GSH or TGA, the GSH-TGA co-capped CdTe QDs demonstrated significantly improved fluorescence intensity and optical stability. In addition, GSH-TGA co-capped CdTe QDs were conjugated to amonoclonal antibody ND-1. The GSH-TGA co-capped CdTe QDs-antibody probe was successfully used to label colorectal cancer cells, CCL187, in vitro.


Assuntos
Compostos de Cádmio/química , Neoplasias Colorretais/patologia , Glutationa/química , Temperatura Alta , Imagem Molecular , Pontos Quânticos , Telúrio/química , Tioglicolatos/química , Humanos
10.
Luminescence ; 26(2): 86-92, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-20017130

RESUMO

Functionalized CdTe-CdS core-shell quantum dots (QDs) were synthesized in aqueous solution via water-bathing combined hydrothermal method using L-cysteine (L-Cys) as a stabilizer. This method possesses both the advantages of water-bathing and hydrothermal methods for preparing high-quality QDs with markedly reduced synthesis time, and better stability than a lone hydrothermal method. The QDs were characterized by transmission electronic microscopy and powder X-ray diffraction and X-ray photoelectron spectroscopy. The CdTe-CdS QDs with core-shell structure showed both enhanced fluorescence and better photo stability than nude CdTe QDs. After conjugating with antibody rabbit anti-CEACAM8 (CD67), the as-prepared l-Cys capped CdTe-CdS QDs were successfully used as fluorescent probes for the direct immuno-labeling and imaging of HeLa cells. It was indicated that this kind of QD would have application potential in bio-labeling and cell imaging.


Assuntos
Compostos de Cádmio/química , Cisteína/química , Imagem Molecular/métodos , Pontos Quânticos , Sulfetos/química , Telúrio/química , Compostos de Cádmio/síntese química , Células HeLa , Humanos , Imuno-Histoquímica , Sulfetos/síntese química
11.
Nanoscale ; 2(7): 1141-8, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20648340

RESUMO

A new kind of magnetic/luminescent multifunctional nanoparticles was synthesized by covalently linking multiple carboxyl-functionalized superparamagnetic Fe(3)O(4) nanoparticles and individual amino-functionalized silica-coated fluorescent NaYF(4) : Yb,Er up-conversion nanoparticles (UCNPs). The resultant nanocomposites bear active carboxylic and amino groups on the surface that were proved to be chemically active and useful for further facile bioconjugation with biomolecules. The UCNPs in the nanocomposite particles can emit visible light in response to the irradiation by near infrared (NIR) light, enabling the application of the nanocomposites in bioimaging. X-Ray diffraction, infrared spectroscopy, transmission electron microscopy, luminescence spectroscopy, and magnetometry were applied to characterize the multifunctional nanocomposites. The nanocomposites exhibited good superparamagnetic and excellent green up-conversion photoluminescent properties that can be exploited in magnetic separation and guiding as well as bioimaging. Due to the presence of active functional groups on the nanocomposite surface, the Fe(3)O(4)/NaYF(4) : Yb,Er magnetic/luminescent nanocomposites were successfully conjugated with a protein called transferrin, which specifically recognizes the transferrin receptors overexpressed on HeLa cells, and can be employed for biolabeling and fluorescent imaging of HeLa cells. Because NIR light can penetrate biological samples with good depth without damaging them and can avoid autofluorescence from them, the presence of both NIR-responsive UCNPs and superparamagnetic nanoparticles in the nanocomposite particles will enable the practical application of the nanocomposites in bioimaging and separation.


Assuntos
Óxido Ferroso-Férrico/química , Corantes Fluorescentes/química , Magnetismo , Nanopartículas Metálicas/química , Metais Terras Raras/química , Érbio/química , Fluoretos/química , Células HeLa , Humanos , Nanopartículas Metálicas/ultraestrutura , Microscopia de Fluorescência , Neoplasias , Espectrofotometria Infravermelho , Itérbio/química , Ítrio/química
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