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1.
Perioper Med (Lond) ; 13(1): 22, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38539254

RESUMO

BACKGROUND: Residual neuromuscular blockade (rNMB) remains a persistent and preventable problem, with serious risks. METHODS: Our objective was to describe and assess patterns in the use of neuromuscular blocking agents (NMBAs), neuromuscular transmission (NMT) monitoring, and factors associated with the use of sugammadex. We performed a retrospective, observational cohort study based on electronic medical records in a large teaching hospital in the Netherlands that introduced an integrated NMT monitoring module with automatic recording in 2017. A total of 22,000 cases were randomly selected from all surgeries between January 2015 and December 2019 that required endotracheal intubation with the use of an NMBA. A total of 14,592 cases fulfilled all the inclusion criteria for complete analyses. RESULTS: Relative NMBA usage remained the same over time. For rocuronium, spontaneous reversal decreased from 86 to 81%, sugammadex reversal increased from 12 to 18%. There was a decline in patients extubated in the operating room (OR) with neither documented NMT monitoring nor sugammadex-mediated reversal from 46 to 31%. The percentage of patients extubated in the OR without a documented train-of-four ratio ≥ 0.9, decreased from 77 to 56%. Several factors were independently associated with the use of sugammadex, including BMI > 30 kg/m2 (odds ratio: 1.41; 95% CI: 1.24-1.60), ASA class 3 or 4 (1.20; 1.07-1.34), age > 60 years (1.37; 1.23-1.53), duration of surgery < 120 min (3.01; 2.68-3.38), emergency surgery (1.83; 1.60-2.09), laparoscopic surgery (2.01; 1.71-2.36), open abdominal/thoracic surgery (1.56; 1.38-1.78), NMT monitoring used (5.31; 4.63-6.08), total dose of rocuronium (1.99; 1.76-2.25), and (inversely) use of inhalational anaesthetics (0.88; 0.79-0.99). CONCLUSION: Our data demonstrate that the implementation of NMT monitoring with automatic recording coincides with a gradual increase in the (documented) use of NMT monitoring and an increased use of sugammadex with a more precise dose. Factors associated with sugammadex use include higher age, ASA score, BMI, abdominal and thoracic surgery, higher rocuronium doses, emergency surgery and the use of NMT monitoring. Trial registration N/A. KEY POINTS: • Introduction of NMT monitoring with automatic recording coincides with an increase in (documented) use of NMT monitoring. • Sugammadex is more frequently used in patients with a presumed higher a priori risk of pulmonary complications. • Despite increased NMT monitoring and use of sugammadex a significant percentage of patients remain at potential risk of rNMB.

2.
Arch Phys Med Rehabil ; 105(2): 280-286, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37541358

RESUMO

OBJECTIVE: To evaluate the trends in the incidence of major limb amputations and the prevalence of Dutch prosthetic users at the national level in The Netherlands between 2012 and 2021 (during the COVID-19 pandemic). Local hospitals in The Netherlands reported a doubling of major lower limb amputations during COVID-19, information about a change in the incidence of major upper limb amputations was not reported. We could not confirm this remarkable increase in major lower limb amputations in our institution, nor did we observe a change in the incidence of major upper limb amputations. We hypothesize that the COVID-19 pandemic had no effect on the number of major limb amputations. DESIGN: Observational retrospective study analyzing national open-access databases of health insurance claims. SETTING: The Dutch national opensource database www.opendisdata.nl was used to retrieve the incidence of limb amputations in the period 2012-2021, stratified by the level of amputation and the cause of amputation. The results were verified using the www.gipdatabank.nl databank. This period included 4 intervals of nationwide COVID-19 lockdowns. PARTICIPANTS: 60,848 patients who underwent limb amputations at the upper or lower extremity in the Netherlands from 2012 to 2021 (N=60,848) were included in this study. INTERVENTION: Not applicable. MAIN OUTCOME MEASURES: Upper- and lower-limb amputation and prosthetic use. RESULTS: Data were retrieved for a total of 60,848 patients in the Netherlands, who underwent 68,180 amputations of the upper and lower extremities at any level from 2012 to 2021, including 22,095 major amputations of the lower extremities. The ongoing trend of stable numbers of major lower-limb amputations from 2012 to 2019 continued in 2020 and 2021. The verification of these data at the level of prosthetic users confirmed that the annual trends were unchanged. CONCLUSION: The reported increased numbers of major lower-limb amputations during the COVID-19 pandemic in the Netherlands could not be confirmed using nationwide epidemiologic data.


Assuntos
COVID-19 , Pandemias , Humanos , Estudos Retrospectivos , Países Baixos/epidemiologia , COVID-19/epidemiologia , Controle de Doenças Transmissíveis , Amputação Cirúrgica , Extremidade Inferior/cirurgia
3.
Rapid Commun Mass Spectrom ; 30(8): 1019-30, 2016 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-27003039

RESUMO

RATIONALE: Continuous-flow reaction detection systems (monitoring enzymatic reactions with mass spectrometry (MS)) lack quantitative values so far. Therefore, two independent internal standards (IS) are implemented in a way that the online system stability can be observed, quantitative conversion values for substrate and product can be obtained and they can be used as mass calibration standards for high MS accuracy. METHODS: An application previously developed for the MS detection of peptide phosphorylation by cAMP-dependent protein kinase A (PKA) (De Boer et al., Anal. Bioanal. Chem. 2005, 381, 647-655) was transferred to a continuous-flow reaction detection system. This enzymatic reaction, involving enzyme activation as well as the transfer of a phosphate group from ATP to a peptide substrate, was used to prove the compatibility of a quantitative enzymatic assay in a continuous-flow real-time system (connected to MS). RESULTS: Moreover (using internal standards), the critical parameter reaction temperature (including solution density variations depending on temperature) was studied in the continuous-flow mixing system. Furthermore, two substrates (malantide and kemptide), two enzyme types (catalytic subunit of PKA and complete PKA) and one inhibitor were tested to determine system robustness and long-term availability. Even spraying solutions that contained significant amount of MS contaminants (e.g. the polluted catalytic subunit) resulted in quantifiable MS signal intensities. Subsequent recalculations using the internal standards led to results representing the power of this application. CONCLUSIONS: The presented methodology and the data evaluation with available Achroma freeware enable the direct coupling of biochemical assays with quantitative MS detection. Monitoring changes such as temperature, reaction time, inhibition, or compound concentrations can be observed quantitatively and thus enzymatic activity can be calculated.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Ensaios Enzimáticos/métodos , Espectrometria de Massas/métodos , Software , Ensaios Enzimáticos/normas , Espectrometria de Massas/normas , Modelos Químicos , Oligopeptídeos/análise , Oligopeptídeos/metabolismo , Peptídeos/análise , Peptídeos/metabolismo , Fosforilação , Padrões de Referência , Processamento de Sinais Assistido por Computador
4.
Biology (Basel) ; 2(3): 894-917, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24833052

RESUMO

Fimbriae are long, proteinaceous adhesion organelles expressed on the bacterial envelope, evolutionarily adapted by Escherichia coli strains for the colonization of epithelial linings. Using glycan arrays of the Consortium for Functional Glycomics (CFG), the lectin domains were screened of the fimbrial adhesins F17G and FedF from enterotoxigenic E. coli (ETEC) and of the FimH adhesin from uropathogenic E. coli. This has led to the discovery of a more specific receptor for F17G, GlcNAcb1,3Gal. No significant differences emerged from the glycan binding profiles of the F17G lectin domains from five different E. coli strains. However, strain-dependent amino acid variations, predominantly towards the positively charged arginine, were indicated by sulfate binding in FedF and F17G crystal structures. For FedF, no significant binders could be observed on the CFG glycan array. Hence, a shotgun array was generated from microvilli scrapings of the distal jejunum of a 3-week old piglet about to be weaned. On this array, the blood group A type 1 hexasaccharide emerged as a receptor for the FedF lectin domain and remarkably also for F18-fimbriated E. coli. F17G was found to selectively recognize glycan species with a terminal GlcNAc, typifying intestinal mucins. In conclusion, F17G and FedF recognize long glycan sequences that could only be identified using the shotgun approach. Interestingly, ETEC strains display a large capacity to adapt their fimbrial adhesins to ecological niches via charge-driven interactions, congruent with binding to thick mucosal surfaces displaying an acidic gradient along the intestinal tract.

5.
Biochem Soc Trans ; 39(1): 349-54, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21265802

RESUMO

FimH is the type 1 fimbrial tip adhesin and invasin of Escherichia coli. Its ligands are the glycans on specific proteins enriched in membrane microdomains. FimH binding shows high-affinity recognition of paucimannosidic glycans, which are shortened high-mannose glycans such as oligomannose-3 and -5. FimH can recognize equally the (single) high-mannose glycan on uroplakin Ia, on the urinary defence protein uromodulin or Tamm-Horsfall glycoprotein and on the intestinal GP2 glycoprotein present in Peyer's patches. E. coli bacteria may attach to epithelial cells via hundreds of fimbriae in a multivalent fashion. This binding is considered to provoke conformational changes in the glycoprotein receptor that translate into signalling in the cytoplasm of the infected epithelial cell. Bladder cell invasion by the uropathogenic bacterium is the prelude to recurrent and persistent urinary tract infections in humans. Patients suffering from diabetes mellitus are more prone to contract urinary tract infections. In a study of women, despite longer treatments with a more potent antibiotic, these patients also have more often recurrences of urinary tract infections compared with women without diabetes. Type 1 fimbriae are the most important virulence factors used not only for adhesion of E. coli in the urinary tract, but also for the colonization by E. coli in patients with Crohn's disease or ulcerative colitis. It appears that the increased prevalence of urinary tract infections in diabetic women is not the result of a difference in the bacteria, but is due to changes in the uroepithelial cells leading to an increased adherence of E. coli expressing type 1 fimbriae. Hypothetically, these changes are in the glycosylation of the infected cells. The present article focuses on possible underlying mechanisms for glycosylation changes in the uroepithelial cell receptors for FimH. Like diabetes, bacterial adhesion induces apoptosis that may bring the endoplasmic reticulum membrane with immature mannosylated glycoproteins to the surface. Indicatively, clathrin-mediated vesicle trafficking of glucose transporters is disturbed in diabetics, which would interfere further with the biosynthesis and localization of complex N-linked glycans.


Assuntos
Suscetibilidade a Doenças , Infecções Urinárias/metabolismo , Adesinas de Escherichia coli/química , Adesinas de Escherichia coli/metabolismo , Animais , Aderência Bacteriana , Feminino , Proteínas de Fímbrias/química , Proteínas de Fímbrias/metabolismo , Fímbrias Bacterianas/química , Fímbrias Bacterianas/metabolismo , Glicosilação , Humanos , Masculino , Análise em Microsséries , Polissacarídeos/química , Polissacarídeos/metabolismo , Ligação Proteica , Infecções Urinárias/microbiologia , Escherichia coli Uropatogênica/metabolismo , Escherichia coli Uropatogênica/patogenicidade , Urotélio/citologia , Urotélio/metabolismo
6.
Mass Spectrom Rev ; 28(2): 192-206, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-18979527

RESUMO

Hydrophilic interaction chromatography (HILIC) with mass spectrometry is a versatile technique for structural glycomics. Glycans are retained by hydrogen bonding, ionic interactions, and dipole-dipole interactions. Glycopeptides as well as glycans with various modifications and reducing-end labels can be efficiently separated, which often results in the resolution of isobaric species. Chromatography is usually performed with solvent mixtures of organic modifier (often acetonitrile) and volatile (acidic) buffer which are suitable for online-electrospray ionization-mass spectrometry. When performed at the nano-scale, this results in a detection limit for oligosaccharides of approximately 1 femtomol. Alternatively, glycans may be analyzed by offline-MALDI-MS(/MS) in both negative-ion mode and positive-ion mode, which allows the registration of informative fragment ion spectra from deprotonated species and sodium adducts, respectively. (c) 2009 Wiley Periodicals, Inc., Mass Spec Rev 28:192-206, 2009.


Assuntos
Cromatografia/métodos , Cromatografia/tendências , Glicômica/métodos , Glicômica/tendências , Espectrometria de Massas/métodos , Espectrometria de Massas/tendências
7.
Proteomics Clin Appl ; 3(1): 106-15, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21136940

RESUMO

In several autoimmune disorders, including rheumatoid arthritis (RA), autoantibodies are thought to be the driving force of pathogenicity. Glycosylation of the Fc-part of human Igs is known to modulate biological activity. Hitherto, glycosylation of human IgG-Fc has been analyzed predominantly at the level of total serum IgG, revealing reduced galactosylation in RA. Given the pathogenic relevance of autoantibodies in RA, we wished, in the present study, to address the question whether distinct Fc-glycosylation features are observable at the level of antigen-specific IgG subpopulations. For this purpose, we have developed a method for the microscale purification and Fc-glycosylation analysis of anti-citrullinated peptide antibodies (ACPA). ACPA represent a group of autoantibodies that occur with unique specificity in RA patients. Their presence is associated with increased inflammatory disease activity and rapid joint destruction. Results indicate that ACPA of the IgG1 subclass vary considerably from total serum IgG1 with respect to Fc-galactosylation, with galactosylation being higher on ACPA than on serum IgG1 for some patients, while other patients show higher galactosylation on serum IgG1 than on ACPA. Using this method, studies can be performed on the biological and clinical relevance of ACPA glycosylation within RA patient cohorts.

8.
Anal Chem ; 80(15): 6119-26, 2008 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-18593198

RESUMO

Many diseases are associated with changes in the glycosylation of plasma proteins. To search for glycan biomarkers, large sample sets have to be investigated for which high-throughput sample preparation and analysis methods are required. We here describe a 96 well plate-based high-throughput procedure for the rapid preparation of 2-aminobenzoic acid (2-AA) labeled N-glycans from 10 microL of human plasma. During this procedure, N-glycans are released from glycoproteins and subsequently labeled with 2-AA without prior purification. A hydrophilic interaction chromatography (HILIC)-based solid phase extraction method is then applied to isolate the 2-AA labeled N-glycans, which can be analyzed by MALDI-TOF-MS, HPLC with fluorescence detection, and CE-MS. The relative standard deviation for the intrabatch repeatability and the interbatch repeatability of the sample preparation method remained below 7% and below 9%, respectively, for all peaks observed by HPLC. Similar results were obtained with MALDI-TOF-MS, where 47 N-glycans could be measured consistently. The 2-AA labeled N-glycans were additionally analyzed by a CE-ESI-Q-TOF-MS method, which featured high resolution and mass accuracy, allowing the unambiguous determination of the N-glycan compositions. Up to four times, 96 human plasma samples can be handled in parallel, which, together with the versatility of the 2-AA label, makes this procedure very attractive for glycomics analysis of larger sample cohorts.


Assuntos
Cromatografia/métodos , Glicoproteínas/sangue , Polissacarídeos/análise , Cromatografia Líquida de Alta Pressão , Técnicas de Laboratório Clínico , Glicosilação , Humanos , Espectrometria de Massas , Extração em Fase Sólida
9.
Glycoconj J ; 25(1): 75-84, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18193481

RESUMO

A surface plasmon resonance (SPR) based natural glycan microarray was developed for screening of interactions between glycans and carbohydrate-binding proteins (CBPs). The microarray contained 144 glycan samples and allowed the real-time and simultaneous screening for recognition by CBPs without the need of fluorescent labeling. Glycans were released from their natural source and coupled by reductive amination with the fluorescent labels 2-aminobenzamide (2AB) or anthranilic acid (AA) followed by high-performance liquid chromatography (HPLC) fractionation making use of the fluorescent tag. The released and labeled glycans, in addition to fluorescently labeled synthetic glycans and (neo)glycoproteins, were printed on an epoxide-activated chip at fmol amounts. This resulted in covalent immobilization, with the epoxide groups forming covalent bonds to the secondary amine groups present on the fluorescent glycoconjugates. The generated SPR glycan array presented a subset of the glycan repertoire of the human parasite Schistosoma mansoni. In order to demonstrate the usefulness of the array in the simultaneous detection of glycan-specific serum antibodies, the anti-glycan antibody profiles from sera of S. mansoni-infected individuals as well as from non-endemic uninfected controls were recorded. The SPR screening was sensitive for differences between infection sera and control sera, and revealed antibody titers and antibody classes (IgG or IgM). All SPR analyses were performed with a single SPR array chip, which required regeneration and blocking of the chip before the application of a serum sample. Our results indicate that SPR-based arrays constructed from glycans of natural or synthetic origin, pure or as mixture, can be used for determining serum antibody profiles as possible markers for the infection status of an individual.


Assuntos
Anticorpos/sangue , Anticorpos/imunologia , Glicômica/métodos , Análise em Microsséries/métodos , Polissacarídeos/análise , Polissacarídeos/imunologia , Ressonância de Plasmônio de Superfície/métodos , Animais , Biomarcadores/sangue , Humanos , Estrutura Molecular , Polissacarídeos/química , Schistosoma mansoni/imunologia , Esquistossomose mansoni/sangue , Esquistossomose mansoni/imunologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
10.
Anal Chem ; 79(21): 8107-13, 2007 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-17922555

RESUMO

We here present a printed covalent glycan microarray for protein-binding studies, using low-femtomole quantities of glycans. Glycans, either natural glycans, which were released from glycoproteins and glycolipids from natural sources, or synthetic glycans, were labeled with common fluorescent labels (e.g., 2-aminobenzamide or 2-aminobenzoic acid) by reductive amination and purified by HPLC. The purified glycoconjugates were covalently immobilized on commercial epoxide-activated glass slides via the secondary amine group that links the glycan moiety with the fluorescent tag. This immobilization procedure is generally applicable to reductively aminated glycans with different established fluorescent labels and allows the spatial arrangement of oligosaccharides. The microarray comprised a variety of natural glycans from various biological sources and synthetic glycans and provided informative binding fingerprints for the lectin concanavalin A as well as 14 monoclonal antibodies. Recognized glycans were characterized by tandem mass spectrometry revealing binding motifs. This natural glycan array allowed the characterization of the specificity of carbohydrate-binding proteins for oligosaccharide ligands from sparse biological sources. Moreover, it was applied for the characterization of the microarray glycans by using known carbohydrate-binding proteins.


Assuntos
Polissacarídeos/análise , Análise Serial de Proteínas/métodos , Anticorpos Monoclonais/análise , Concanavalina A/análise , Estrutura Molecular , Sensibilidade e Especificidade , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Espectrometria de Massas em Tandem/métodos
11.
Anal Chem ; 77(24): 7894-900, 2005 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-16351135

RESUMO

The potential of high-temperature liquid chromatography (HTLC) was investigated in an on-line combination with a screening system for bioactive compounds against the enzyme cathepsin B. Samples were separated by HTLC and subsequently analyzed by an on-line continuous-flow enzymatic assay. Detection was performed by electrospray ionization mass spectrometry, revealing both the bioactivity and the molecular mass of the bioactive compounds. Compared to conventional reversed-phase liquid chromatography, the amount of methanol necessary for separation could be decreased to only 10%, which improved the compatibility of LC with a biochemical assay. Sufficient preheating of the mobile phase prior to the separation and postcolumn cooling to prevent deactivation of the enzyme, even at column temperatures as high as 208 degrees C, was achieved as indicated by the reliable peak shapes obtained. The sensitivity was comparable with previously described systems operating at ambient temperatures as similar IC50 values were obtained. Exposing the inhibitors to high temperatures did not lead to thermal decomposition. The separation of inhibitors and the subsequent biochemical assay was performed either isothermally at various temperatures or by applying various temperature gradients as well as at various flow rates. The results obtained clearly show the compatibility of HTLC with an enzymatic screening assay.


Assuntos
Cromatografia Líquida/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Catepsina B/metabolismo , Dipeptídeos/análise , Estabilidade de Medicamentos , Temperatura Alta , Leucina/análogos & derivados , Leucina/análise , Leupeptinas/análise , Sistemas On-Line , Sensibilidade e Especificidade , Chá/química
12.
Lab Chip ; 5(11): 1286-92, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16234953

RESUMO

The design and implementation of a continuous-flow microfluidic assay for the screening of (complex) mixtures for bioactive compounds is described. The microfluidic chip featured two microreactors (1.6 and 2.4 microL) in which an enzyme inhibition and a substrate conversion reaction were performed, respectively. Enzyme inhibition was detected by continuously monitoring the products formed in the enzyme-substrate reaction by electrospray ionization mass spectrometry (ESI-MS). In order to enable the screening of mixtures of compounds, the chip-based assay was coupled on-line to capillary reversed-phase high-performance liquid chromatography (HPLC) with the HPLC column being operated either in isocratic or gradient elution mode. In order to improve the detection limits of the current method, sample preconcentration based on a micro on-line solid-phase extraction column was employed. The use of electrospray MS allowed the simultaneous detection of chemical (MS spectra) and biological parameters (enzyme inhibition) of ligands eluting from the HPLC column. The present system was optimized and validated using the protease cathepsin B as enzyme of choice. Inhibition of cathepsin B is detected by monitoring three product traces, obtained by cleavage of the substrate. The two microreactors provided 32 and 36 s reaction time, respectively, which resulted in sufficient assay dynamics to enable the screening of bioactive compounds. The total flow rate was 4 microL min-1, which a 25-fold decrease was compared with a macro-scale system described earlier. Detection limits of 0.17-2.6 micromol L-1 were obtained for the screening of inhibitors, which is comparable to either microtiter plate assays or continuous-flow assays described in the literature.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Microfluídica/instrumentação , Microfluídica/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Catepsina B/metabolismo , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Sensibilidade e Especificidade
13.
Anal Chem ; 76(11): 3155-61, 2004 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-15167796

RESUMO

Liquid chromatography (LC) was coupled on-line to a continuous-flow enzymatic assay using electrospray ionization mass spectrometry (ESI-MS) as readout for the screening of enzyme inhibitors in complex samples. Inhibitors were detected by changes in the concentration of the enzymatic reaction products, indicating the inhibition of enzymatic activity. The molecular masses of the inhibitors were determined with high certainty by using retention time matching and peak shape comparison. Due to the high matching accuracy, baseline separation of coeluting analytes was not necessary in order to identify the correct masses of the bioactive compounds. The continuous-flow system was successfully applied for the screening of complex samples, such as natural extracts. For a red clover extract, detection limits of 0.3-0.8 micromol/L were obtained. System validation was performed by determining the IC(50) values of four inhibitors in the flow-injection mode. The IC(50) values were in the 0.11-5.6 micromol/L range and correspond closely to data obtained by microtiter plate assays. Detection limits were in the range of 0.018-0.35 micromol/L in the flow-injection mode, and 0.075-0.75 micromol/L in the LC mode. These values are well below the typical compound concentrations (1-10 micromol/L) used in high-throughput screening. Together with an interday precision of 12.6%, these results demonstrate the applicability of the system for bioactivity screening of complex mixtures, generating both chemical and biological information on bioactive compounds in a single run.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Inibidores Enzimáticos/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Animais
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