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Accurate identification of glycan structures is highly desirable as they are intimately linked to their different functions. However, glycan samples generally exist as mixtures with multiple isomeric structures, making assignment of individual glycan components very challenging, even with the aid of multistage mass spectrometry (MSn). Here, we present an approach, GIPS-mix, for assignment of isomeric glycans within a mixture using an intelligent group-opting strategy. Our approach enumerates all possible combinations (groupings) of candidate glycans and opts in the best-matched glycan group(s) based on the similarity between the simulated spectra of each glycan group and the acquired experimental spectra of the mixture. In the case that a single group could not be elected, a tie break is performed by additional MSn scanning using intelligently selected precursors. With 11 standard mixtures and 6 human milk oligosaccharide fractions, we demonstrate the application of GIPS-mix in assignment of individual glycans in mixtures with high accuracy and efficiency.
Assuntos
Oligossacarídeos , Polissacarídeos , Humanos , Polissacarídeos/química , Oligossacarídeos/análise , Isomerismo , Leite Humano/químicaRESUMO
Measuring the concentrations of steroid hormones in plasma is critical for understanding their role in various vital physiological processes. The detection of underivatized steroid hormones in biofluids through mass spectrometry (MS) is typically hindered by low ionization efficiency. We described a novel matrix-assisted laser desorption/ionization-MS (MALDI-MS) approach based on hydroxylamine derivatization (HA-D) to analyze low-concentration steroid hormones in plasma. The ketonic carbonyl group containing steroid hormones could be derivatized using HA to form oxime derivatives, which considerably enhanced the MS sensitivity for detecting steroid hormones. By using the optimized conditions, estrone (E1), testosterone (T), and progesterone (Prog), could be simultaneously quantified in plasma with a limit of detection (LOD) from 0.019 to 0.031 nM, recoveries from 86% to 108%, and coefficient of variation (CV%) from 4.59% to 11.90%. HA-D/MALDI-MS exhibited higher sensitivity than those using Girard T (GT). To establish potential utility of our method, we characterized fatty liver patient plasmas to demonstrate that the HA-D/MALDI-MS procedure could generate quantitative results comparable to the current clinical liquid chromatography-electrospray ionization tandem MS (LC-ESI MS/MS) method. This approach facilitates the rapid and accurate characterization of plasma hormones, and renders the MALDI-MS approach for steroid hormones more adaptable for clinical research and use.
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Ensaios de Triagem em Larga Escala/métodos , Hormônios/análise , Hormônios/química , Hidroxilaminas/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Bioensaio , Fígado Gorduroso/sangue , Hormônios/sangue , Humanos , Limite de Detecção , Extração em Fase Sólida , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em TandemRESUMO
Immunoglobulin G (IgG) is a class of monoclonal antibodies (mAbs) commonly produced in mammalian cell lines. These cell lines are grown in finely adjusted culture media, which contain components that may impact glycoforms. As variation of N-glycoforms can impact the biological properties of IgGs, medium composition should be controlled. Here, we studied the effects on IgG N-glycoforms of different components in hybridoma culture media, specifically compared bovine serum albumin (BSA) with other small molecules, using a matrix-assisted laser desorption/ionization quadrupole ion trap time-of-flight multistage mass spectrometry (MALDI-QIT-TOF MSn)-based approach. We show that small molecular additives caused little change in glycan species, though a number of these reagents, especially glutamine, affected levels of glycosylation. In comparison, the addition of macromolecular protein BSA significantly changed IgG N-glycan patterns, not only in species but also in glycosylation levels. Together, our finding suggests that BSA increases the complexity of IgG N-glycoforms, thus raising the difficulty in maintaining glycoforms consistency during antibody production. Therefore, the effect of BSA on IgG N-glycans should be considered when designing optimal medium formulations for IgG production. KEY POINTS: ⢠Small molecular medium additives only affect glycosylation levels of IgG N-glycans. ⢠BSA significantly changes IgG N-glycoforms as a medium additive. ⢠BSA's skewing of IgG N-glycoforms should be considered in IgG production.
Assuntos
Anticorpos Monoclonais/química , Meios de Cultura/química , Hibridomas/imunologia , Imunoglobulina G/química , Soroalbumina Bovina/farmacologia , Animais , Anticorpos Monoclonais/isolamento & purificação , Bovinos , Linhagem Celular , Glicosilação , Imunoglobulina G/isolamento & purificação , Camundongos , Oligossacarídeos/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por MatrizRESUMO
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/químicaRESUMO
Glycosylation is a post-translational modification essential for maintaining the structure and function of proteins. Abnormal N-glycan patterns have been found in various diseases compared to healthy controls. A decrease in terminal galactosylated N-glycans of serum IgG in rheumatoid arthritis (RA) and osteoarthritis (OA) may be involved in their immunopathogenesis. However, how glycan patterns differ between RA and OA remains unclear. Here, we identified 15 glycan forms of serum IgG from RA and OA using MALDI-TOF MS. We found that IgG galactosylation represented a suitable candidate for differentiating RA from healthy controls (AUC > 0.9). Then, we performed binary logistic regression to screen out three bisecting N-acetylglucosamine (GlcNAc) glycoforms for distinguishing between OA and RA. Combined ROC analysis of the selected glycans yielded an AUC of 0.81 between OA and RA and an AUC of 0.79 between OA and RF/ACPA negative RA. Similar results were found in the validation set. In conclusion, our analysis demonstrates that RA and OA are distinguished on the basis of their different IgG glycan patterns, which thus serve as suitable candidates as biomarkers for reliably identifying clinical conditions such as RA and OA.
Assuntos
Artrite Reumatoide/diagnóstico , Biomarcadores/sangue , Galactose/química , Imunoglobulina G/sangue , Osteoartrite/diagnóstico , Polissacarídeos/sangue , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Idoso , Artrite Reumatoide/sangue , Estudos de Casos e Controles , Diagnóstico Diferencial , Feminino , Glicosilação , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite/sangue , Processamento de Proteína Pós-TraducionalRESUMO
BACKGROUND: stroke patients often have a combination of sleep apnea syndrome, which is an important and modifiable risk factor for stroke prognosis. Acupuncture is one of the measures for sleep apnea syndrome, and it is also widely used in stroke. However, we are concerned that its efficacy and safety in the treatment of stroke with sleep apnea syndrome are not yet clear. METHODS: This systematic review and meta-analysis was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses schema and was registered with INPLASY (registration number: INPLASY202250113). The following 8 databases were searched: PubMed, Cochrane Library (CENTRAL), Embase, Web of Science, China National Knowledge Infrastructure, Chongqing VIP Information, WanFang Data, and China Biomedical Literature Database limited from the establishment of each database to May 4, 2022. Subject headings, free words, and keywords were used for retrieval. Relevant literature was supplemented by consulting other resources. We assessed the risk of bias in the included studies using the Cochrane risk of bias tool. RevMan 5.4 software (The Cochrane Collaboration, 2020) was used to perform the meta-analysis. RESULTS: Six records were included, including a total of 513 participants: 256 in the experimental group and 257 in the control group. The results showed that the total effective rate (relative riskâ =â 1.23, 95% confidence interval (CI): 1.13, 1.34, Pâ <â .00001), apnea-hypopnea index (mean difference (MD)â =â -8.39, 95% CI: -9.19, -7.59, Pâ <â .00001), Epworth Sleepiness Scale score (MDâ =â -1.59, 95% CI: -2.66, -0.52, Pâ =â .004), minimal oxygen saturation (MDâ =â 4.99, 95% CI: 3.5, 6.47, Pâ <â .00001), longest duration of apnea (MDâ =â -7.47, 95% CI: -8.97, -5.97, Pâ <â .00001), longest duration of apnea (MDâ =â -6.48, 95% CI: -8.60, -4.35, Pâ <â .00001), and S100ß levels (standard mean differenceâ =â -1.52, 95% CI: -1.87, -1.18, Pâ <â .00001) were better in the experimental group than in the control group. Simultaneously, the effect of reducing the neuron-specific enolase level in the experimental group was comparable to that in the control group (MDâ =â -3.40, 95% CI: -9.08, 2.29, Pâ =â .24). CONCLUSIONS: Acupuncture can improve the clinical symptoms and related laboratory indicators for sleep apnea syndrome in patients with stroke. More high-quality trials remain urgently needed.
Assuntos
Terapia por Acupuntura , Síndromes da Apneia do Sono , Acidente Vascular Cerebral , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Terapia por Acupuntura/efeitos adversos , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/terapia , Síndromes da Apneia do Sono/complicações , Síndromes da Apneia do Sono/terapia , PrognósticoRESUMO
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.
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Human milk oligosaccharides (HMOs) are structurally diverse unconjugated glycans, and play crucial roles in protecting infants from infections. Preterm birth is one of the leading causes of neonatal mortality, and preterm infants are particularly vulnerable and are in need of improved outcomes from breast-feeding due to the presence of bioactive HMOs. However, studies on specific difference in HMOs as a function of gestation time have been very limited. We established an approach to extract and analyze HMOs based on 96-well plate extraction and mass spectrometry, and determined maternal phenotypes through distinctive fragments in product-ion spectra. We enrolled 85 women delivering at different gestation times (25-41 weeks), and observed different HMOs correlating with gestation time based on 233 samples from the 85 donors. With the increase of postpartum age, we observed a regular changing trajectory of HMOs in composition and relative abundance, and found significant differences in HMOs secreted at different postpartum times. Preterm delivery induced more variations between participants with different phenotypes compared with term delivery, and more HMOs varied with postpartum age in the population of secretors. The sialylation level in mature milk decreased for women delivering preterm while such decrease was not observed for women delivering on term.
Assuntos
Leite Humano , Nascimento Prematuro , Recém-Nascido , Lactente , Feminino , Humanos , Mães , Recém-Nascido Prematuro , Lactação , OligossacarídeosRESUMO
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.
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Tetralogy of Fallot (TOF) is one of the most common cyanotic congenital heart diseases (CHD) worldwide; however, its pathogenesis remains unclear. Recent studies have shown that circular RNAs (circRNAs) act as "sponges" for microRNAs (miRNAs) to compete for endogenous RNA (ceRNA) and play important roles in regulating gene transcription and biological processes. However, the mechanism of ceRNA in TOF remains unclear. To explore the crucial regulatory connections and pathways of TOF, we obtained the human TOF gene, miRNA, and circRNA expression profiling datasets from the Gene Expression Omnibus (GEO) database. After data pretreatment, differentially expressed mRNAs (DEmRNAs), microRNAs (DEmiRNAs), and circRNAs (DEcircRNAs) were identified between the TOF and healthy groups, and a global triple ceRNA regulatory network, including circRNAs, miRNAs, and mRNAs based on the integrated data, was constructed. A functional enrichment analysis was performed on the Metascape website to explore the biological functions of the selected genes. Then, we constructed a protein-protein interaction (PPI) network and identified seven hub genes using the cytoHubba and MCODE plug-ins in the Cytoscape software, including BCL2L11, PIK3R1, SOCS3, OSMR, STAT3, RUNX3, and IL6R. Additionally, a circRNA-miRNA-hub gene subnetwork was established, and its enrichment analysis results indicated that the extrinsic apoptotic signaling pathway, JAK-STAT signaling pathway and PI3K-Akt signaling pathway may be involved in the pathogenesis of TOF. We further identified the hsa_circ_000601/hsa-miR-148a/BCL2L11 axis as a crucial signaling pathway axis from the subnetwork. This study provides a novel regulatory network for the pathogenesis of TOF, revealing the possible molecular mechanisms and crucial regulatory pathways that may provide new strategies for candidate diagnostic biomarkers or potential therapeutic targets for TOF.
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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 químicaRESUMO
The densely glycosylated spike (S) protein highly exposed on severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) surface mediates host cell entry by binding to the receptor angiotensin-converting enzyme 2 (ACE2). However, the role of glycosylation has not been fully understood. In this study, we investigated the effect of different N-glycosylation of S1 protein on its binding to ACE2. Using real-time surface plasmon resonance assay the negative effects were demonstrated by the considerable increase of binding affinities of de-N-glycosylated S1 proteins produced from three different expression systems including baculovirus-insect, Chinese hamster ovarian and two variants of human embryonic kidney 293 cells. Molecular dynamic simulations of the S1 protein-ACE2 receptor complex revealed the steric hindrance and Coulombic repulsion effects of different types of N-glycans on the S1 protein interaction with ACE2. The results should contribute to future pathological studies of SARS-CoV-2 and therapeutic development of Covid-19, particularly using recombinant S1 proteins as models.
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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 , SuínosRESUMO
Biological functions of N-glycans are frequently related to their unique branching patterns. Multistage mass spectrometry (MSn) has become the primary method for glycan structural analysis. However, selection of the best fragment as the precursor for the next round of product-ion scanning is important but difficult. We have previously proposed the concept and designed the approach of glycan intelligent precursor selection (GIPS) to guide MSn experiments, but its use in N-glycans is not straightforward as some N-glycans are of high similarity in branching patterns. In the present work we introduced new elements to GIPS to improve its performance in N-glycan branching pattern analysis. These include a hypothesis and significance test, based on Bayes factor, and DPbiased as a new precursor selection strategy. The improved GIPS was successfully applied to identification of individual N-glycans, and incorporated into MALDI-MS N-glycan profiling for assignment of N-glycans obtained from glycoproteins and complex human serum.
Assuntos
Glicoproteínas/química , Polissacarídeos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Glicoproteínas/sangue , Humanos , Estrutura Molecular , Polissacarídeos/química , Polissacarídeos/classificaçãoRESUMO
OBJECTIVE: Heart failure is a major public health problem worldwide nowadays. However, the morbidity, mortality, and awareness of heart failure are not satisfied as well as the status of current treatments. According to the standard treatment for chronic heart failure (CHFST), Fuzi (the seminal root of Aconitum carmichaelii Debx.) formulae are widely used as a complementary treatment for heart failure in clinical practice for a long time. We are aiming to assess the efficacy and safety of Fuzi formulae (FZF) on the treatment of heart failure according to high-quality randomized controlled trials (RCTs). METHODS: RCTs in PubMed, Cochrane Library, China National Knowledge Infrastructure (CNKI), Chinese Scientific Journals Database (VIP), and Wanfang Database were searched from their inception until June 2019. In addition, the U.S. National Library of Medicine (clinicaltrials.gov) and the Chinese Clinical Trial Registry (http://www.chictr.org.cn) were also searched. We included RCTs that test the efficacy and safety of FZF for the treatment of heart failure, compared with placebo, CHFST, or placebo plus CHFST. The methodological quality of included studies were evaluated by the Cochrane Collaboration's tool for assessing risk of bias. RCTs with Cochrane risk of bias (RoB) score ≥4 were included in the analysis. The meta-analysis was conducted through RevMan 5.2 software. The GRADE approach was used to assess the quality of the evidence. RESULTS: Twelve RCTs with 1490 participants were identified. The studies investigated the efficacy and safety of FZF, such as FZF plus the CHFST vs placebo plus CHFST (n = 4), FZF plus CHFST vs CHFST (n = 6), FZF plus digoxin tablets (DT) plus CHFST vs placebo plus DT plus CHFST (n = 1), and FZF plus placebo plus CHFST vs placebo plus DT plus CHFST (n = 1). Meta-analysis indicated that FZF have additional benefits based on the CHFST in reducing plasma NT-proBNP level, MLHFQ scores, Lee's heart failure scores (LHFs), and composite cardiac events (CCEs). Meanwhile, it also improved the efficacy on TCM symptoms (TCMs), NYHA functional classification (NYHAfc), 6MWD, and LVEF. Adverse events were reported in 6 out of 12 studies without significant statistical difference. However, after assessing the strength of evidence, it was found that only the quality of evidence for CCEs was high, and the others were either moderate or low or very low. So we could not draw confirmative conclusions on its additional benefits except CCEs. Further clinical trials should be well designed to avoid the issues that were identified in this study. CONCLUSION: The efficacy and additional benefits of FZF for CCEs were certain according to the high-quality evidence assessed through GRADE. However, the efficacy and additional benefits for the other outcomes were uncertain judging from current studies. In addition, the safety assessment has a great room for improvement. Thus, further research studies are needed to find more convincing proofs.
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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/métodosRESUMO
Knowledge of blood triacylglycerol (TAG) species is essential to clarify the physiological functions of individual TAG molecules and also to develop potential biomarkers for related diseases. Commonly, lipid samples prepared by organic liquid-liquid extraction contain complex components, thus cannot be directly characterized by mass spectrometry (MS) and often require an additional purification step. Here, we described a laser desorption ionization - mass spectrometry (LDI-MS) method that utilized aggregated graphene oxide (AGO) as both lipid extractant and MS matrix (AGOLDI-MS), to characterize and quantify plasma TAG species without the use of harmful solvent or complex separation step. We first designed and synthesized the AGO material with a multi-layered sheet structure, which could efficiently break up the structure of lipoproteins, and extract plasma TAGs as solid-phase extraction material. Furthermore, in AGOLDI-MS procedure, the AGO could directly act as matrix and selectively produce the MS signals of TAGs without the interferences of phospholipids, which was hardly achieved by using the routine LDI-MS method based on liquid-liquid extraction and small molecular matrix. We confirmed the suitability of AGOLDI-MS as characterization and quantitative tool for TAG species through studying the analysis performances in TAG standards and real plasma samples. To establish potential utility of our method, we characterized 42 human plasmas from healthy and hyperlipemic donators, indicating that the AGOLDI-MS could not only generate comparable quantitative results of total TAGs to current clinical technology, but also monitor the changes of TAG species between different sample groups. This approach could further characterize the compositions of the fatty acid moieties in even low abundant TAGs by the assistance of tandem MS-MS. This concise, specific, and high-throughput approach will facilitate the rapid and precise characterizations of plasma TAGs, and make the MS approach for TAGs more adaptable for clinical uses.
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Ácidos Graxos/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Triglicerídeos/sangue , Adulto , Feminino , Grafite , Humanos , Hiperlipidemias/sangue , Masculino , Pessoa de Meia-Idade , Fosfolipídeos/sangue , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos , Triglicerídeos/análiseRESUMO
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.
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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 TratamentoRESUMO
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 , CicatrizaçãoRESUMO
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.