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1.
Z Rheumatol ; 80(10): 972-979, 2021 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-33931806

RESUMO

In soft tissue tumors of the extremities it is of utmost importance to differentiate between benign and malignant entities. The majority of the swellings vary from benign tissue changes through soft tissue sarcomas up to pseudotumors. Because of the low incidence of malignancy and the predominantly benign alterations together with a high heterogeneity, there is a need for a reproducible diagnostic and therapeutic concept for the treatment of all tumors of the extremities. This article reports the case of a 59-year-old patient with longstanding rheumatoid arthritis who presented to the orthopedic rheumatologic consultation with a massive swelling directly ventral to the knee joint. At that point the tumor had already grown very slowly for 5 years. The staged diagnostic process (patient history, clinical, laboratory tests, sonographic examinations, X­ray, MRI with contrast medium) revealed no trace of malignancy whatsoever. The treatment then consisted of the complete surgical excision in accordance with the recommendations for tumor surgery. Histopathological findings confirmed the diagnosis of a massive prepatellar bursitis. Initially, the extreme and solid prepatellar swelling was suspected of being malignant; however, this could already be broadly excluded preoperatively. This article presents the rationale and the orthopedic rheumatologic approach for addressing unclear space-occupying lesions of the musculoskeletal system in patients with rheumatism. In the inflammatory systemic disease in the differential diagnosis periarticular swellings can ultimately also have benign causes, such as an organized bursitis.


Assuntos
Artrite Reumatoide , Bursite , Neoplasias , Artrite Reumatoide/diagnóstico , Bursite/diagnóstico , Bursite/cirurgia , Humanos , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/cirurgia , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade
2.
Phys Chem Chem Phys ; 20(16): 11412-11417, 2018 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-29645042

RESUMO

Photocleavable tags (PCTs) have the potential for excellent spatio-temporal control over the release of subunits of complex molecules. Here, we show that electrosprayed oligopeptides, functionalized by a tailored ortho-nitroarylether can undergo site-specific photo-activated cleavage under UV irradiation (266 nm) in high vacuum. The comparison of UV photodissociation (UVPD) and collision-induced dissociation (CID) points to the thermal nature of the cleavage mechanism, a picture corroborated by the temperature dependence of the process. Two competing photodissociation pathways can be identified. In one case a phenolate anion is separated from a neutral zwitterion. In the other case a neutral phenol derivative leaves a negatively charged peptide behind. To understand the factors favoring one channel over the other, we investigate the influence of the peptide length, the nature of the phenolic group and the position of the nitro-group (ortho vs. para). The observed gas phase cleavage of a para-nitro benzylic ether markedly differs from the established behavior in solution.


Assuntos
Nitrobenzenos/efeitos da radiação , Oligopeptídeos/efeitos da radiação , Fenóis/efeitos da radiação , Modelos Químicos , Estrutura Molecular , Nitrobenzenos/química , Oligopeptídeos/química , Fenóis/química , Teoria Quântica , Espectrometria de Massas por Ionização por Electrospray , Temperatura , Raios Ultravioleta , Vácuo
3.
Orthopade ; 47(10): 883-896, 2018 10.
Artigo em Alemão | MEDLINE | ID: mdl-30132014

RESUMO

The management of acute pain is of utmost importance in the treatment regimen of orthopedic and trauma patients. Pain perception is different for each patient and has to be individually addressed. Especially in a postoperative setting often with a very dynamic course of pain, it is optimal that the pain management is adapted to the individual course of pain. In this situation it makes sense to apply patient-controlled systems. By combining different analgesic substance classes and non-pharmaceutical therapy in the sense of a multimodal concept, the mechanisms of action complement each other and side effects can be reduced. Patient satisfaction is higher when they are actively involved in the (medicinal) pain therapy and in the decision making. This is particularly important for patient-controlled analgesia (PCA). In addition to invasive catheter administration procedures, there are also modern approaches for oral individual self-administered opioid treatment.


Assuntos
Dor Aguda , Ortopedia , Manejo da Dor , Ferimentos e Lesões , Analgesia Controlada pelo Paciente , Analgésicos Opioides , Humanos , Dor Pós-Operatória , Ferimentos e Lesões/cirurgia
4.
Genet Mol Res ; 14(4): 19110-6, 2015 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-26782563

RESUMO

The aim of the current study was to investigate the association between the InDel polymorphism in the angiotensin I-converting enzyme gene (ACE) and the rs699 polymorphism in the angiotensinogen gene (AGT) and diabetes mellitus type 2 (DM2) in a sample population from Southern Brazil. A case-control study was conducted with 228 patients with DM2 and 183 controls without DM2. The ACE InDel polymorphism was genotyped by polymerase chain reaction (PCR) with specific primers, followed by electrophoresis on 1.5% agarose gel. The AGT rs699 polymorphism was genotyped using a real-time PCR assay. No significant association between the ACE InDel polymorphism and DM2 was detected (P = 0.97). However, regarding the AGT rs699 polymorphism, DM2 patients had a significantly higher frequency of the AG genotype and lower frequency of the GG genotype when compared to the controls (P = 0.03). Our results suggest that there is an association between the AGT rs699 polymorphism and DM2 in a Brazilian sample.


Assuntos
Angiotensinogênio/genética , Diabetes Mellitus Tipo 2/genética , Predisposição Genética para Doença , Mutação INDEL , Peptidil Dipeptidase A/genética , Polimorfismo Genético , Idoso , Alelos , Angiotensinogênio/metabolismo , Brasil , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Feminino , Expressão Gênica , Frequência do Gene , Humanos , Masculino , Pessoa de Meia-Idade , Peptidil Dipeptidase A/metabolismo , Sistema Renina-Angiotensina/genética , Fatores de Risco
5.
Anal Bioanal Chem ; 405(22): 7119-32, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23404132

RESUMO

Second generation advanced high strength steel is one promising material of choice for modern automotive structural parts because of its outstanding maximal elongation and tensile strength. Nonetheless there is still a lack of corrosion protection for this material due to the fact that cost efficient hot dip galvanizing cannot be applied. The reason for the insufficient coatability with zinc is found in the segregation of manganese to the surface during annealing and the formation of manganese oxides prior coating. This work analyses the structure and chemical composition of the surface oxides on so called nano-TWIP (twinning induced plasticity) steel on the nanoscopic scale after hot dip galvanizing in a simulator with employed analytical methods comprising scanning Auger electron spectroscopy (SAES), energy dispersive X-ray spectroscopy (EDX), and focused ion beam (FIB) for cross section preparation. By the combination of these methods, it was possible to obtain detailed chemical images serving a better understanding which processes exactly occur on the surface of this novel kind of steel and how to promote in the future for this material system galvanic protection.

6.
Anal Bioanal Chem ; 405(22): 7133-44, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23831753

RESUMO

In this work, a novel evaluation strategy for the X-ray photoelectron spectroscopy (XPS) chemical assessment is proposed to identify the corrosion products formed on the surface of hot-dip galvanized ZnMgAl coatings after exposure to standardized salt spray tests. The experiments demonstrate that the investigated system exhibits a problematic differential charging behavior between the different compounds, an effect which cannot be fully compensated for by the flood gun of the XPS system, making a reliable evaluation of the individual spectra impossible by using standard evaluation and fitting methods. For that reason, a new effective approach--taking the different charge shifts into account--was implemented and its reliability experimentally verified on model mixtures of assumed corrosion products with known composition. With this new approach, the chemical surface composition of an industrial sample of a corroded ZnMgAl coating was revealed and discussed in order to clearly demonstrate the potential of the proposed method for future corrosion studies.

7.
Anal Bioanal Chem ; 403(3): 651-61, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22086398

RESUMO

In this work, the first few nanometres of the surface of ZnMgAl hot-dip-galvanised steel sheets were analysed by scanning Auger electron spectroscopy, angle-resolved X-ray photoelectron spectroscopy and atomic force microscopy. Although the ZnMgAl coating itself is exhibiting a complex micro-structure composed of several different phases, it is shown that the topmost surface is covered by a smooth, homogeneous oxide layer consisting of a mixture of magnesium oxide and aluminium oxide, exhibiting a higher amount of magnesium than aluminium and a total film thickness of 4.5 to 5 nm. Especially by the combined analytical approach of surface-sensitive methods, it is directly demonstrated for the first time that within surface imprints--created by industrial skin rolling of the steel sheet which ensures a smooth surface appearance as well as reduced yield-point phenomenon--the original, smooth oxide layer is partly removed and that a layer of native oxides, exactly corresponding to the chemical structure of the underlying metal phases, is formed.

8.
Anal Bioanal Chem ; 403(3): 663-73, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22362274

RESUMO

Zn-Cr alloyed coatings electrochemically deposited are of high interest for leading steel manufacturing companies because of their novel properties and high corrosion resistance compared with conventional Zn coatings on steel. For tuning and optimizing the properties of the electrodeposited Zn-Cr coatings, a broad range of the deposition conditions must be studied. For this reason, two different types of material were investigated in this study, one with a low electrolyte temperature and one with an elevated electrolyte pH, compared with the standard values. Because different corrosion performance and delamination behaviour of the layers were observed for the two types, advanced surface analysis was conducted to understand the origin of this behaviour and to discover differences in the formation of the coatings. The topmost surface, the shallow subsurface region, and the whole bulk down to the coating-steel interface surface were analysed in detail by X-ray photoelectron spectroscopy (XPS) and high-resolution scanning Auger electron spectroscopy to determine the elemental and the chemical composition. For better understanding of the resulting layer structure, multiple reference samples and materials were measured and their Auger and XPS spectra were fitted to the experimental data. The results showed that one coating type is composed of metallic Zn and Cr, with oxide residing only on the surface and interface, whereas the other type contains significant amounts of Zn and Cr oxides throughout the whole coating thickness.

9.
Nat Commun ; 11(1): 1447, 2020 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-32193414

RESUMO

The de Broglie wave nature of matter is a paradigmatic example of quantum physics and it has been exploited in precision measurements of forces and fundamental constants. However, matter-wave interferometry has remained an outstanding challenge for natural polypeptides, building blocks of life, which are fragile and difficult to handle. Here, we demonstrate the wave nature of gramicidin, a natural antibiotic composed of 15 amino acids. Its center of mass is delocalized over more than 20 times the molecular size in our time-domain Talbot-Lau interferometer. We compare the observed interference fringes with a model that includes both a rigorous treatment of the peptide's quantum wave nature as well as a quantum chemical assessment of its optical properties to distinguish our result from classical predictions. The realization of quantum optics with this prototypical biomolecule paves the way for quantum-assisted measurements on a large class of biologically relevant molecules.


Assuntos
Gramicidina/química , Modelos Químicos , Peptídeos/química , Teoria Quântica , Interferometria , Fótons , Raios Ultravioleta
10.
Transplant Proc ; 40(4): 981-2, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18555095

RESUMO

UNLABELLED: The short cold ischemic tolerance of the gut is a major problem in small bowel transplantation. We have shown that intestinal lipid administration is beneficial during systemic inflammation like sepsis. METHODS: Rats were intestinally infused with either water or 1% olive oil for 12 hours. The small bowel was removed and stored in HTK solution on ice. At t = 0, t = 60, t = 120, t = 180, t = 240, t = 300, t = 360, t = 420, and t = 480 minutes, a tissue sample of the gut was fixed, stained, and analyzed by three independent observers. Damage score was calculated (0 = no damage, 1 = minor damage, 2 = major damage, 3 = loss of structure) for integrity of the mucosa, integrity of the basal membrane of the mucosa, and integrity of villy. The damage score was allocated when all three observers agreed on the same or a higher damage score. RESULTS: In all control animals minor damage for the integrity of the basal membrane occurred within 60 minutes, but in only 50% of the lipid-treated rats. In all control rats, major damage for both integrity of mucosa and villi occurred within 300 minutes or less, but only in 50% of the lipid-treated rats. In all control rats, the structure of the villi was completely lost within 480 minutes or less, whereas only 50% of the lipid treated animals reached maximal damage scores for either mucosa or villi. CONCLUSION: Intestinal lipid administration before cold storage clearly decreases histologic damage of the small bowel and might increase the tolerance for cold ischemia. Lipids or their metabolites stored in enterocytes may act as an antiinflammatory. Intestinal lipid administration in organ donors might be useful to increase cold ischemic tolerance of the small bowel.


Assuntos
Absorção Intestinal , Intestino Delgado/fisiopatologia , Isquemia/fisiopatologia , Lipídeos/fisiologia , Óleos de Plantas/farmacologia , Animais , Mucosa Intestinal/efeitos dos fármacos , Intestino Delgado/irrigação sanguínea , Intestino Delgado/efeitos dos fármacos , Masculino , Azeite de Oliva , Soluções para Preservação de Órgãos , Ratos , Ratos Sprague-Dawley
11.
Ecotoxicol Environ Saf ; 70(2): 334-40, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18068780

RESUMO

The effects of the insecticidal Cry1Ab protein from Bacillus thuringiensis (Bt) on the nematode, Caenorhabditis elegans, were studied with soil from experimental fields cultivated with transgenic Bt corn (MON810) and with trypsinized Cry1Ab protein expressed in Escherichia coli. The content of Cry1Ab protein was above the detection limit of an ELISA test in only half of the soil samples obtained from transgenic plots, ranging from 0.19 to 1.31 ng g(-1) dry weight. In a laboratory bioassay, C. elegans was exposed to rhizosphere and bulk soil from fields with isogenic or transgenic corn or to solutions of Cry1Ab protein (0, 24, 41, 63, 118, and 200 mg l(-1)) over a period of 96 h, with growth and reproduction serving as the test parameters. Nematode reproduction and growth were significantly reduced in rhizosphere and bulk soil of Bt corn compared with soil from isogenic corn and were significantly correlated with concentrations of the Cry1Ab protein in the soil samples. Moreover, the toxicity of pure Cry1Ab protein to the reproduction and growth of C. elegans was concentration-dependent. As significant inhibition occurred at relatively high concentrations of the Cry1Ab protein (41 mg l(-1)), the effects of the soil samples from Bt corn could not be assigned directly to the toxicity of the Cry1Ab protein. The results demonstrate that bioassays with the nematode, C. elegans, provide a promising tool for monitoring the potential effects of Bt toxins in aqueous medium and soils.


Assuntos
Proteínas de Bactérias/toxicidade , Caenorhabditis elegans/efeitos dos fármacos , Endotoxinas/toxicidade , Proteínas Hemolisinas/toxicidade , Inseticidas/toxicidade , Plantas Geneticamente Modificadas , Zea mays/genética , Animais , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/genética , Caenorhabditis elegans/fisiologia , Endotoxinas/genética , Escherichia coli/genética , Proteínas Hemolisinas/genética , Nível de Efeito Adverso não Observado , Reprodução/efeitos dos fármacos
12.
Nanoscale ; 9(26): 9175-9180, 2017 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-28650054

RESUMO

We explore the synthesis, characterization, neutral launch and vacuum ultraviolet ionization of massive perfluorinated-alkyl-capped nanoparticles. The presence of the ligand coating in solution is corroborated by Fourier transform infrared spectroscopy (FT-IR) and the particle size distribution is analyzed by transmission electron microscopy (TEM). Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry identifies perfluoralkyl coated silver nanoparticles as the most stable species among the materials studied here. They can be launched in high vacuum using long-pulse low-power laser heating - orders of magnitude below typical thresholds for laser desorption. Energy-dispersive X-ray spectroscopy (EDX) of the recaptured silver clusters confirms the expected elemental distribution. Volatilization with subsequent ionization of the neutral nanoparticle beam in high vacuum by 157 nm light allows analyzing their mass with atomic resolution.

13.
J Mass Spectrom ; 52(8): 550-556, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28608445

RESUMO

Amino acids are essential building blocks of life, and fluorinated derivatives have gained interest in chemistry and medicine. Modern mass spectrometry has enabled the study of oligo- and polypeptides as isolated entities in the gas phase, but predominantly as singly or even multiply charged species. While laser desorption of neutral peptides into adiabatically expanding supersonic noble gas jets is possible, UV-VIS spectroscopy, electric or magnetic deflectometry as well as quantum interferometry would profit from the possibility to prepare thermally slow molecular beams. This has typically been precluded by the fragility of the peptide bond and the fact that a peptide would rather 'fry', i.e. denature and fragment than 'fly'. Here, we explore how tailored perfluoroalkyl functionalization can reduce the intermolecular binding and thus increase the volatility of peptides and compare it to previously explored methylation, acylation and amidation of peptides. We show that this strategy is essential and enables the formation of thermal beams of intact neutral tripeptides, whereas only fragments were observed for an extensively fluoroalkyl-decorated nonapeptide. © 2017 The Authors. Journal of Mass Spectrometry Published by John Wiley & Sons Ltd.


Assuntos
Oligopeptídeos/análise , Oligopeptídeos/síntese química , Sequência de Aminoácidos , Sítios de Ligação , Flúor , Isomerismo , Espectrometria de Massas , Ligação Proteica , Conformação Proteica , Estabilidade Proteica , Volatilização
14.
Curr Opin Neurobiol ; 3(4): 586-94, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8219726

RESUMO

Recently, the classic idea of a 'relational' code in the brain received new impetus from the observation of stimulus-dependent synchronizations in the visual cortex. Work over the past two years has focused on documenting the functional dependencies of such synchronizations. We review and classify the experimental findings with respect to separate spatial and temporal schemes. Thus, we distinguish between different signal classes (spikes, continuous signals), and different types of time-locking to the stimulus. These various classes of synchronization phenomena are discussed with regard to their properties, the underlying mechanisms and their possible relevance for visual processing.


Assuntos
Mamíferos/fisiologia , Neurônios/fisiologia , Córtex Visual/fisiologia , Percepção Visual/fisiologia , Animais , Percepção Espacial/fisiologia , Fatores de Tempo
15.
Org Lett ; 8(2): 301-4, 2006 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-16408900

RESUMO

[reaction: see text] A mixture of four stereoisomers whose configurations are encoded by fluorous silyl protecting groups has been prepared and converted over 22 steps to a mixture of protected dictyostatins. Demixing by fluorous HPLC followed by removal of the fluorous protecting groups (detagging) provides dictyostatin and three C6,C7 stereoisomers. Biological evaluation showed that the monoepimers of the natural product retained highly potent activity.


Assuntos
Flúor/química , Macrolídeos/síntese química , Macrolídeos/química , Estrutura Molecular , Estereoisomerismo
16.
Circulation ; 101(23): 2678-81, 2000 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-10851203

RESUMO

BACKGROUND: Previous studies have suggested that atrial fibrillation (AF) is associated with the activation of the atrial angiotensin system. However, it is not known whether the expression of angiotensin II receptors changes during AF. The purpose of this study was to determine the atrial expression of angiotensin II type 1 and type 2 receptors (AT(1)-R and AT(2)-R) in patients with AF. METHODS AND RESULTS: Atrial tissue samples from 30 patients undergoing open heart surgery were examined. Eleven patients had chronic persistent AF (> or =6 months; cAF), 8 patients had paroxysmal AF (pAF), and 11 patients were in sinus rhythm. AT(1)-R and AT(2)-R were localized in the atrial tissue by immunohistochemistry and quantified at the protein and mRNA level by Western blotting and quantitative polymerase chain reaction. Both types of AT-R were predominantly expressed in atrial myocytes in all groups. The amount of AT(1)-R was reduced to 34.9% during cAF (P<0.01) and to 51.7% during pAF (P<0.05) compared with patients in sinus rhythm. In contrast, AT(2)-R was increased during cAF (246%; P=NS) and pAF (505%; P<0.01). AT(1)-R/AT(2)-R mRNA content was similar in all groups. CONCLUSIONS: AF is associated with the down-regulation of atrial AT(1)-R and the up-regulation of AT(2)-R proteins. These findings may help define the pathophysiological role of the angiotensin system in the structural remodeling of the fibrillating atria.


Assuntos
Fibrilação Atrial/metabolismo , Miocárdio/metabolismo , Receptores de Angiotensina/genética , Receptores de Angiotensina/metabolismo , Adulto , Idoso , Fibrilação Atrial/fisiopatologia , Western Blotting , Feminino , Expressão Gênica/fisiologia , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Miocárdio/química , RNA Mensageiro/análise , Receptor Tipo 1 de Angiotensina , Receptor Tipo 2 de Angiotensina , Receptores de Angiotensina/análise
17.
J Am Coll Cardiol ; 35(6): 1669-77, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10807475

RESUMO

OBJECTIVES: The purpose of this study was to determine whether atrial expression of the extracellular signal-regulated kinases Erk1/Erk2 and of the angiotensin-converting enzyme (ACE) is altered in patients with atrial fibrillation (AF). BACKGROUND: Recent studies have demonstrated that atrial fibrosis can provide a pathophysiologic substrate for AF. However, the molecular mechanisms responsible for the development of atrial fibrosis are unclear. METHODS: Atrial tissue samples of 43 patients undergoing open heart surgery were examined. Seventeen patients had chronic persistent AF (> or =6 months; CAF), 8 patients had paroxysmal AF (PAF) and 18 patients had no history of AF. Erk expression was analyzed at the mRNA (quantitative reverse transcription polymerase chain reaction), the protein (immunoblot techniques) and atrial tissue (immunohistochemistry) levels. Erk-activating kinases (MEK1/2) and ACE were analyzed by immunoblot techniques. RESULTS: Increased amounts of Erk2-mRNA were found in patients with CAF (75 +/- 20 U vs. sinus rhythm: 31 +/- 25 U; p < 0.05). Activated Erk1/Erk2 and MEK1/2 were increased to more than 150% in patients with AF compared to patients with sinus rhythm. No differences between CAF and PAF were found. The expression of ACE was three-fold increased during CAF. Amounts of activated Erk1/Erk2 were reduced in patients treated with ACE inhibitors. Patients with AF showed an increased expression of Erk1/Erk2 in interstitial cells and marked atrial fibrosis. CONCLUSIONS: An ACE-dependent increase in the amounts of activated Erk1/Erk2 in atrial interstitial cells may contribute as a molecular mechanism for the development of atrial fibrosis in patients with AF. These findings may have important impact on the treatment of AF.


Assuntos
Fibrilação Atrial/genética , Átrios do Coração/patologia , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/genética , Peptidil Dipeptidase A/genética , Idoso , Fibrilação Atrial/patologia , Fibrose Endomiocárdica/genética , Fibrose Endomiocárdica/patologia , Feminino , Regulação Enzimológica da Expressão Gênica/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Proteína Quinase 3 Ativada por Mitógeno , RNA Mensageiro/genética
18.
Org Lett ; 7(3): 379-82, 2005 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-15673244

RESUMO

[reaction: see text] An esterification/ring-closing metathesis approach to dictyostatin and discodermolide is introduced. The approach provides for facile fragment coupling of two main segments of these natural products at the C10-C11 alkene with high to complete Z-selectivity.


Assuntos
Macrolídeos/síntese química , Alcanos/química , Carbamatos/química , Ésteres/química , Indicadores e Reagentes , Lactonas/química , Conformação Molecular , Oxirredução , Pironas/química , Relação Estrutura-Atividade
19.
Arch Intern Med ; 150(8): 1629-33, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2116785

RESUMO

Apolipoprotein A-I and B concentrations were measured in 502 patients undergoing diagnostic cardiac catheterization to assess the predictive power of apolipoproteins B and A-I to discriminate between patients with coronary artery disease and those with normal coronary arteries as defined by coronary arteriography. The strength of the associations was compared with that of the associations between traditional risk factors (eg, smoking status, cholesterol levels) and coronary artery disease. The study population consisted of 154 women (mean age, 62.9 years) and 348 men (mean age, 59.6 years). The apolipoprotein A-I concentration averaged (+/- SD) 124 +/- 25 mg/dL and the apolipoprotein B concentration, 98 +/- 24 mg/dL. In all cases, the apolipoprotein measures showed a larger univariate difference between the "normal" (no coronary artery disease) group (66 patients) and the group with coronary artery disease (436 patients) than did the corresponding standard lipoprotein measures. The variable with the strongest association with coronary artery disease was the ratio of apolipoprotein A-I to apolipoprotein B, followed by apolipoprotein B level. These findings were confirmed using logistic regression, adjusting for other coronary artery disease risk factors. Fasting status did not affect apolipoprotein A-I or B concentrations. We conclude that the use of apolipoprotein A-I and B concentrations gives additional information to that supplied by lipoprotein measures to help predict the presence of coronary artery disease. Since traditional lipid measures may be changed by a meal, apolipoproteins A-I and B might be more useful measures when the fasting status of a patient is in question.


Assuntos
Apolipoproteínas A/sangue , Apolipoproteínas B/sangue , Doença das Coronárias/sangue , Lipoproteínas HDL/sangue , Apolipoproteína A-I , Angiografia Coronária , Doença das Coronárias/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Fatores de Risco
20.
Nat Commun ; 6: 7336, 2015 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-26066053

RESUMO

Matter-wave interferometry can be used to probe the foundations of physics and to enable precise measurements of particle properties and fundamental constants. It relies on beam splitters that coherently divide the wave function. In atom interferometers, such elements are often realised using lasers by exploiting the dipole interaction or through photon absorption. It is intriguing to extend these ideas to complex molecules where the energy of an absorbed photon can rapidly be redistributed across many internal degrees of freedom. Here, we provide evidence that center-of-mass coherence can be maintained even when the internal energy and entropy of the interfering particle are substantially increased by absorption of photons from a standing light wave. Each photon correlates the molecular center-of-mass wave function with its internal temperature and splits it into a superposition with opposite momenta in addition to the beam-splitting action of the optical dipole potential.

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