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1.
Carbohydr Polym ; 319: 121201, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37567725

RESUMO

Pentosan polysulfate sodium (PPS) is a semi-synthetic, heparin-like polysaccharide with manifold therapeutic actions. It is approved for treatment of bladder pain syndrome / interstitial cystitis in humans and treatment of musculoskeletal diseases in animals. PPS is produced by a complex procedure using beech wood as starting material. It consists of a mixture of sulfated glucuronoxylans, whose structural composition cannot be fully characterized by physicochemical analysis. The question arises whether PPS follow-on products are identical with the original and thus meet the requirement for generic drug application. The aim of this study was to investigate whether commercially available PPS products differ in physicochemical characteristics and biological effects from the original. Ten PPS preparations from different manufactures were analyzed using orthogonal analytical techniques including, inter alia, size exclusion chromatography with triple detection, nuclear magnetic resonance spectroscopy, and high-resolution mid-infrared spectroscopy in aqueous solution with chemometric evaluation. For functional analysis, we measured the plasma kallikrein generation in human plasma and FXII activation. The study revealed significant structural and biological differences between PPS from different sources. Therefore, follow-on products cannot be considered identical but at best similar to original PPS. However, their similar efficacy and safety have still to be proven by comprehensive studies.

2.
Diagnostics (Basel) ; 13(3)2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36766463

RESUMO

Both relevant aortic valve stenosis (AS) and aortic valve insufficiency significantly contribute to structural changes in the ascending aorta (AA) and thus to its dilatation. In patients with severe AS undergoing transcatheter aortic valve replacement (TAVR), survival data regarding aortic changes and laboratory biomarker analyses are scarce. METHODS: A total of 179 patients with severe AS and an available computed tomography were included in this retrospective study. AA was measured, and dilatation was defined as a diameter ≥ 40 mm. Thirty-two patients had dilatation of the AA. A further 32 patients from the present population with a normal AA were matched to the aortic dilatation group with respect to gender, age, body mass index and body surface area, and the resulting study groups were compared with each other. In addition to echocardiographic and clinical characteristics, the expression of cardiovascular biomarkers such as brain natriuretic peptide (BNP), soluble suppression of tumorigenicity-2 (sST2), growth/differentiation of factor-15 (GDF-15), heart-type fatty-acid binding protein (H-FABP), insulin-like growth factor binding protein 2 (IGF-BP2) and soluble urokinase-type plasminogen activator receptor (suPAR) was analyzed. Kaplan-Meier curves for short- and long-term survival were obtained, and Pearson's and Spearman's correlations were calculated to identify the predictors between the diameter of the AA and clinical parameters. RESULTS: A total of 19% of the total cohort had dilatation of the AA. The study group with an AA diameter ≥ 40 mm showed a significantly low comorbidity with respect to diabetes mellitus in contrast to the comparison cohort with an AA diameter < 40 mm (p = 0.010). This result continued in the correlation analyses performed, as the presence of diabetes mellitus correlated negatively not only with the diameter of the AA (r = -0.404; p = 0.001) but also with the presence of aortic dilatation (r = -0.320; p = 0.010). In addition, the presence of AA dilatation after TAVR was shown to have no differences in terms of patient survival at 1, 3 and 5 years. There were no relevant differences in the cardiovascular biomarkers studied between the patients with dilated and normal AAs. CONCLUSION: The presence of AA dilatation before successful TAVR was not associated with a survival disadvantage at the respective follow-up intervals of 1, 3 and 5 years. Diabetes mellitus in general seemed to have a protective effect against the development of AA dilatation or aneurysm in patients with severe AS.

3.
J Pers Med ; 12(9)2022 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-36143238

RESUMO

BACKGROUND: Patients with severe aortic valve stenosis (AS) often present with heart failure and sarcopenia. Sarcopenia, described as progressive degradation of skeletal muscle mass, has frequently been implicated as a cause of increased mortality, prolonged hospitalization and generalized poor outcome after transcatheter aortic valve replacement (TAVR). At present, sarcopenia is defined by the European Working Group on Sarcopenia in Older People (EWGSOP) based on clinical examination criteria and radiological imaging. The aim of the present study was to compare patients with Computed Tomography (CT)-diagnosed sarcopenia with regard to the expression of cardiovascular biomarkers in order to obtain additional, laboratory-chemical information. METHODS: A total of 179 patients with severe AS were included in this retrospective study. Sarcopenia was determined via CT by measurement of the psoas muscle area (PMA), which was indexed to body surface area (PMAi). According to previous studies, the lowest tertile was defined as sarcopenic. Patients with (59/179) and without sarcopenia (120/179) in the overall cohort were compared by gender-specific cut-offs with regard to the expression of cardiovascular biomarkers such as brain natriuretic peptide (BNP), soluble suppression of tumorigenicity-2 (sST2), growth/differentiation of factor-15 (GDF-15), heart-type fatty-acid binding protein (H-FABP), insulin like growth factor binding protein 2 (IGF-BP2) and soluble urokinase-type plasminogen activator receptor (suPAR). Additionally, binary logistic regression analyses were calculated to detect possible predictors of the presence of sarcopenia. RESULTS: No statistical differences regarding one-year survival could be detected between sarcopenic and non-sarcopenic patients in survival curves (log rank test p = 0.179). In the entire cohort, only BNP and hemoglobin (HB) showed a statistically significant difference, with only HB emerging as a relevant predictor for the presence of sarcopenia after binary logistic regression analysis (p = 0.015). No relevant difference in biomarker expression could be found in the male cohort. Regarding the female cohort, statistically significant differences were found in BNP, HB and hematocrit (HK). In binary logistic regression, however, none of the investigated criteria could be related to sarcopenia. CONCLUSION: Regardless of gender, patients with imaging-based muscle degradation did not demonstrate significantly different cardiovascular biomarker expression compared to those without it.

4.
Thromb Haemost ; 122(6): 984-997, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35322395

RESUMO

Two years since the outbreak of the novel coronavirus SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) pandemic, there remain few clinically effective drugs to complement vaccines. One is the anticoagulant, heparin, which in 2004 was found able to inhibit invasion of SARS-CoV (CoV-1) and which has been employed during the current pandemic to prevent thromboembolic complications and moderate potentially damaging inflammation. Heparin has also been shown experimentally to inhibit SARS-CoV-2 attachment and infection in susceptible cells. At high therapeutic doses however, heparin increases the risk of bleeding and prolonged use can cause heparin-induced thrombocytopenia, a serious side effect. One alternative, with structural similarities to heparin, is the plant-derived, semi-synthetic polysaccharide, pentosan polysulfate (PPS). PPS is an established drug for the oral treatment of interstitial cystitis, is well-tolerated, and exhibits weaker anticoagulant effects than heparin. In an established Vero cell model, PPS and its fractions of varying molecular weights inhibited invasion by SARS-CoV-2. Intact PPS and its size-defined fractions were characterized by molecular weight distribution and chemical structure using nuclear magnetic resonance spectroscopy and liquid chromatography-mass spectrometry, then employed to explore the structural basis of interactions with SARS-CoV-2 spike protein receptor-binding domain (S1 RBD) and the inhibition of Vero cell invasion. PPS was as effective as unfractionated heparin, but more effective in inhibiting cell infection than low-molecular-weight heparin (on a weight/volume basis). Isothermal titration calorimetry and viral plaque-forming assays demonstrated size-dependent binding to S1 RBD and inhibition of Vero cell invasion, suggesting the potential application of PPS as a novel inhibitor of SARS-CoV-2 infection.


Assuntos
Poliéster Sulfúrico de Pentosana , SARS-CoV-2 , Ligação Viral , Animais , Anticoagulantes/farmacologia , Chlorocebus aethiops , Heparina/uso terapêutico , Poliéster Sulfúrico de Pentosana/farmacologia , Ligação Proteica , SARS-CoV-2/efeitos dos fármacos , Glicoproteína da Espícula de Coronavírus , Células Vero , Ligação Viral/efeitos dos fármacos
5.
Rev Cardiovasc Med ; 23(7): 224, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39076911

RESUMO

Background: Patients with severe aortic valve stenosis (AS) frequently present with pulmonary hypertension (PH). The gold standard for detection of pulmonary hypertension is right heart catheterization, which is not routinely performed as a preoperative standard in cardiology centers today, neither before surgical valve replacement nor before transcatheter aortic valve replacement (TAVR) procedure. Echocardiographic determination of systolic pulmonary artery pressure (sPAP) provides an opportunity to assess the presence or absence of PH. The aim of the present study was to investigate the extent to which plasma levels of common cardiovascular biomarkers behave in patients with severe AS and an sPAP < 40 mmHg in comparison to patients with an sPAP ≥ 40 mmHg. Methods: 179 patients with echocardiographic evidence of severe AS before TAVR procedure were divided into 2 groups based on sPAP. An sPAP of 40 mmHg was considered the cut-off value, with absence of PH defined by an sPAP < 40 mmHg (n = 82) and presence of PH defined by an sPAP ≥ 40 mmHg (n = 97). Directly before TAVR, a blood sample was drawn from each patient, and plasma concentrations of the cardiovascular biomarkers Soluble Suppression of Tumorigenicity-2 (sST2), Growth/Differentiation of Factor-15 (GDF-15), Heart-Type Fatty-Acid Binding Protein (H-FABP), Insulin Like Growth Factor Binding Protein 2 (IGF-BP2), Soluble Urokinase-Type Plasminogen Activator Receptor (suPAR), Brain Natriuretic Peptide (BNP) and Cardiac Troponin I (cTnI) were determined. Results: Patients with an sPAP ≥ 40 mmHg had significantly higher sST2 (p = 0.010), GDF-15 (p = 0.005), IGF-BP2 (p = 0.029), suPAR (p = 0.018), BNP (p < 0.001) and cTnI (p = 0.039) plasma levels. Only for H-FABP (p = 0.069), no significant differences were discernible between the two groups. In addition, cut-off values were calculated to predict an sPAP ≥ 40 mmHg. Significant results were shown with 16045.84 pg/mL for sST2 (p = 0.010), with 1117.54 pg/mL for GDF-15 (p = 0.005), with 107028.43 pg/mL for IGF-BP2 (p = 0.029), with 3782.84 pg/mL for suPAR (p = 0.018), with 2248.00 pg/mL for BNP (p < 0.001) and with 20.50 pg/mL for cTnI (p = 0.002). Conclusions: sPAP as an echocardiographic parameter in combination with supplementary use of cardiovascular biomarkers presented here have the potential to provide more detailed information about the presence or absence of PH in a non-invasive way.

6.
J Clin Lab Anal ; 35(11): e23977, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34562276

RESUMO

BACKGROUND: Systemic inflammation has been identified as a major cardiovascular risk factor in patients undergoing transcatheter aortic valve replacement (TAVR), yet currently, it is not adequately portrayed in scores for pre-interventional risk assessment. The aim of this study was to investigate the predictive ability of TNF-α in TAVR. METHODS: A total of 431 patients undergoing transfemoral TAVR were enrolled in this study. Blood samples were drawn prior to intervention, 24 h post-intervention, 4, 5, and 7 days post-intervention, and 1, 3, and 6 months post-TAVR. RESULTS: In a univariate Cox proportional hazard analysis, plasma concentrations of TNF-α after 24 h and after 5 days were associated with mortality after 12 months (after 24 h: HR 1.002 (1.000-1.004), p = 0.028; after 5d: HR 1.003 (1.001-1.005), p = 0.013). This association remained significant even after correction for confounders in a multivariate Cox regression analysis. Additionally, cut-offs were calculated. Patients above the cut-off for TNF-α after 5d had a significantly worse 12-month mortality than patients below the cut-off (18.8% vs. 2.8%, p = 0.046). CONCLUSION: Plasma levels of TNF-α after 24 h and 5 days were independently associated with 12-month mortality in patients undergoing TAVR. Thus, TNF-α could represent a novel biomarker for enhanced risk stratification in these patients.


Assuntos
Substituição da Valva Aórtica Transcateter , Fator de Necrose Tumoral alfa/sangue , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Feminino , Humanos , Inflamação , Masculino , Fatores de Risco , Substituição da Valva Aórtica Transcateter/efeitos adversos , Substituição da Valva Aórtica Transcateter/mortalidade
7.
Wien Med Wochenschr ; 171(15-16): 356-362, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33765204

RESUMO

Two different strands of hair taken from Beethoven's head after his death were examined for heavy metals using scanning electron microscopy (SEM) and laser ablation-ICP-MS (inductively coupled plasma-mass spectroscopy). The results revealed the presence of small lead particles on the surface of Beethoven's hairs and fluctuating lead levels in hair medulla along the length of the hair due to alternating lead exposure, with an average lead exposure of 100 times the normal value. The time-line attached to the peaks of these fluctuating values correlate with the pneumonia treatment and the paracenteses performed, including the subsequent treatment of the procedure wounds. While the administration of lead-containing drugs and treatments had been proven to resolve the pneumonia, it had simultaneously caused massive liver failure, accelerated by pre-existing cirrhosis. The question as to whether Beethoven's death was a case of malpractice can only be answered from a forensic point of view ex ante, since the state of the medical knowledge of the time has to be taken into account.


Assuntos
Pessoas Famosas , Terapia a Laser , Imperícia , Humanos , Chumbo
8.
Am J Cardiol ; 140: 69-77, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33152317

RESUMO

Patients with symptomatic, drug-refractory atrial fibrillation (AF) are frequently treated with catheter ablation. Cryo-ablation has been established as an alternative to radiofrequency ablation but long-term outcome data are still limited. This study aimed at elucidating the influence of the left atrial volume index (LAVI), derived from cardiac computed tomography (cCT) data, on the long-term outcome of ablation-naïve AF patients, after their first cryo-ablation. 415 patients (n = 290 [69.90%] male, 60.00 [IQR: 53.00 to 68.00] years old) who underwent a cCT and subsequent cryo-ablation index procedure were included in this single centre retrospective data analysis. A composite end point was defined (AF on electrocardiogram and/or electric cardioversion and/or re-do). Patients were closely followed for a year and then contacted for long-term follow-up after a median of 53.00 months (IQR: 34.50 to 73.00). Statistical analyses of the outcome and predictors of AF recurrence were conducted. In 224 patients (53.98%) no evidence of AF recurrence could be found. LAVI differed significantly between the positive and adverse (AF recurrence) outcome group (49.96 vs 56.07 ml/m2, p < 0.001). Cox regression analyses revealed cCT LAVI (HR: 1.022, 95% CI: 1.013 to 1.031, p < 0.001), BMI (HR: 1.044, 95% CI: 1.005 to 1.084, p < 0.05) and the type of AF (HR: 1.838 for nonparoxysmal AF, 95% CI: 1.214 to 2.781, p < 0.01) to be effective predictors of AF recurrence. A prognostic cCT LAVI cut-off value of 51.99 ml/m2 was calculated and must be validated in future prospective studies. In conclusion, LAVI is an accurate, yet underutilized predictor of AF recurrence after pulmonary vein isolation with cryo-energy and scores for calculating AF recurrence or progression risks might underemphasize the importance of CT-derived LAVI as a predictive factor.


Assuntos
Fibrilação Atrial/diagnóstico , Função do Átrio Direito/fisiologia , Criocirurgia/métodos , Eletrocardiografia , Átrios do Coração/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Idoso , Fibrilação Atrial/fisiopatologia , Fibrilação Atrial/cirurgia , Volume Cardíaco , Feminino , Seguimentos , Átrios do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
9.
J Clin Med ; 9(7)2020 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-32674397

RESUMO

BACKGROUND: Hereditary transthyretin amyloidosis (hATTR) is an autosomal dominantly inherited disorder caused by an accumulation of amyloid fibrils in tissues due to mutations in the transthyretin (TTR) gene. The prevalence of hATTR is still unclear and likely underestimated in many countries. In order to apply new therapies in a targeted manner, early diagnosis and knowledge of phenotype-genotype correlations are mandatory. This study aimed to assess the prevalence and phenotypic spectrum of hATTR in Austria. METHODS: Within the period of 2014-2019, patients with ATTR-associated cardiomyopathy and/or unexplained progressive polyneuropathies were screened for mutations in the TTR gene. RESULTS: We identified 43 cases from 22 families carrying 10 different TTR missense mutations and confirmed two mutational hot spots at c.323A>G (p.His108Arg) and c.337G>C (p.Val113Leu). Two further patients with late onset ATTR carried TTR variants of unknown significance. The majority of patients initially presented with heart failure symptoms that were subsequently accompanied by progressive polyneuropathy in most cases. A total of 55% had a history of carpal tunnel syndrome before the onset of other organ manifestations. CONCLUSIONS: Our study underlined the relevance of hATTR in the pathogenesis of amyloid-driven cardiomyopathy and axonal polyneuropathy and indicated considerable genetic heterogeneity of this disease in the Austrian population. The estimated prevalence of hATTR in Austria based on this study is 1:200,000 but a potentially higher number of unknown cases must be taken into account. With respect to new therapeutic approaches, we strongly propose genetic testing of the TTR gene in an extended cohort of patients with unexplained heart failure and progressive polyneuropathy.

10.
Microcirculation ; 25(7): e12491, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30027659

RESUMO

OBJECTIVE: Acute myocarditis is accompanied by an impaired coronary microcirculation. These microcirculatory disturbances are not well defined, and data are derived from complex invasive measurements. Therefore, this study aimed to evaluate the inflammation-induced microcirculatory dysfunction including its reversibility and association with markers of inflammation severity (extent of LGE on CMR imaging and laboratory markers of myocardial necrosis) using the noninvasive technique of echocardiographic CFR measurement. METHODS: Patients (n = 14) with clinically suspected acute myocarditis in the absence of coronary artery disease were prospectively enrolled, and echocardiographic CFR was determined by measuring peak diastolic coronary blood flow velocity at rest (PDV1) and under adenosine-induced hyperemia (PDV2) at baseline and 3-month follow-up. RESULTS: Eight of 14 (57.1%) patients showed an impaired baseline CFR (PDV2/PDV1 < 2). These patients were characterized by higher levels of cardiac troponin T (0.55 ± 0.39 vs 0.18 ± 0.08; P = 0.008) and larger areas of LGE on CMR. At 3-month follow-up, CFR was normal in all patients. CONCLUSION: A reversibly impaired coronary microcirculation is a frequent finding in acute myocarditis and is associated with markers of inflammation severity. Echocardiographic CFR measurement represents a feasible and safe method for its assessment.


Assuntos
Circulação Coronária , Vasos Coronários/fisiopatologia , Microcirculação , Miocardite/fisiopatologia , Doença Aguda , Velocidade do Fluxo Sanguíneo , Vasos Coronários/diagnóstico por imagem , Ecocardiografia , Feminino , Humanos , Inflamação/fisiopatologia , Masculino , Pessoa de Meia-Idade , Miocardite/diagnóstico por imagem , Medição de Risco
11.
Electrophoresis ; 39(4): 569-580, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29131355

RESUMO

A fast and precise affinity capillary electrophoresis (ACE) method has been applied to investigate the interactions between two serum albumins (HSA and BSA) and heparinoids. Furthermore, different free flow electrophoresis methods were developed to separate the species which appears owing to interaction of albumins with pentosan polysulfate sodium (PPS) under different experimental conditions. For ACE experiments, the normalized mobility ratios (∆R/Rf ), which provided information about the binding strength and the overall charge of the protein-ligand complex, were used to evaluate the binding affinities. ACE experiments were performed at two different temperatures (23 and 37°C). Both BSA and HSA interact more strongly with PPS than with unfractionated and low molecular weight heparins. For PPS, the interactions can already be observed at low mg/L concentrations (3 mg/L), and saturation is already obtained at approximately 20 mg/L. Unfractionated heparin showed almost no interactions with BSA at 23°C, but weak interactions at 37°C at higher heparin concentrations. The additional signals also appeared at higher concentrations at 37°C. Nevertheless, in most cases the binding data were similar at both temperatures. Furthermore, HSA showed a characteristic splitting in two peaks especially after interacting with PPS, which is probably attributable to the formation of two species or conformational change of HSA after interacting with PPS. The free flow electrophoresis methods have confirmed and completed the ACE experiments.


Assuntos
Eletroforese Capilar/métodos , Heparinoides/química , Heparinoides/metabolismo , Albumina Sérica/química , Albumina Sérica/metabolismo , Humanos , Poliéster Sulfúrico de Pentosana/química , Poliéster Sulfúrico de Pentosana/metabolismo , Ligação Proteica , Temperatura
12.
Clin Med (Lond) ; 17(1): 46-47, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28148580

RESUMO

In this article, we report on a 22-year-old patient with myocardial infarction, which was the initial manifestation of polycythaemia vera. The awareness of myeloproliferative disorders as possible underlying disease - especially in young patients presenting with myocardial infarction - is crucial for clinical management, as a missed diagnosis can worsen the patient's further prognosis.


Assuntos
Oclusão Coronária , Infarto do Miocárdio , Policitemia Vera/complicações , Adulto , Humanos , Masculino , Adulto Jovem
13.
Sci Rep ; 6: 20895, 2016 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-26876950

RESUMO

Dynamic Nuclear Polarization (DNP) has been introduced to overcome the sensitivity limitations of nuclear magnetic resonance (NMR) spectroscopy also of supported lipid bilayers. When investigated by solid-state NMR techniques the approach typically involves doping the samples with biradicals and their investigation at cryo-temperatures. Here we investigated the effects of temperature and membrane hydration on the topology of amphipathic and hydrophobic membrane polypeptides. Although the antimicrobial PGLa peptide in dimyristoyl phospholipids is particularly sensitive to topological alterations, the DNP conditions represent well its membrane alignment also found in bacterial lipids at ambient temperature. With a novel membrane-anchored biradical and purpose-built hardware a 17-fold enhancement in NMR signal intensity is obtained by DNP which is one of the best obtained for a truly static matrix-free system. Furthermore, a membrane anchor sequence encompassing 19 hydrophobic amino acid residues was investigated. Although at cryotemperatures the transmembrane domain adjusts it membrane tilt angle by about 10 degrees, the temperature dependence of two-dimensional separated field spectra show that freezing the motions can have beneficial effects for the structural analysis of this sequence.


Assuntos
Anti-Infecciosos/química , Peptídeos Catiônicos Antimicrobianos/química , Bicamadas Lipídicas/química , Espectroscopia de Ressonância Magnética/métodos , Fosfatidilcolinas/química , Sequência de Aminoácidos , Temperatura Baixa , Dimiristoilfosfatidilcolina/química , Interações Hidrofóbicas e Hidrofílicas , Espectroscopia de Ressonância Magnética/instrumentação , Fosfatidilgliceróis/química
14.
J Phys Chem B ; 119(46): 14574-83, 2015 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-26487390

RESUMO

Dynamic nuclear polarization has been developed to overcome the limitations of the inherently low signal intensity of NMR spectroscopy. This technique promises to be particularly useful for solid-state NMR spectroscopy where the signals are broadened over a larger frequency range and most investigations rely on recording low gamma nuclei. To extend the range of possible investigations, a triple-resonance flat-coil solid-state NMR probe is presented with microwave irradiation capacities allowing the investigation of static samples at temperatures of 100 K, including supported lipid bilayers. The probe performance allows for two-dimensional separated local field experiments with high-power Lee-Goldberg decoupling and cross-polarization under simultaneous irradiation from a gyrotron microwave generator. Efficient cooling of the sample turned out to be essential for best enhancements and line shape and necessitated the development of a dedicated cooling chamber. Furthermore, a new membrane-anchored biradical is presented, and the geometry of supported membranes was optimized not only for good membrane alignment, handling, stability, and filling factor of the coil but also for heat and microwave dissipation. Enhancement factors of 17-fold were obtained, and a two-dimensional PISEMA spectrum of a transmembrane helical peptide was obtained in less than 2 h.


Assuntos
Bicamadas Lipídicas , Ressonância Magnética Nuclear Biomolecular/métodos , Peptídeos/química , Espectroscopia de Ressonância Magnética
15.
PLoS One ; 7(9): e44450, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22973451

RESUMO

We have conducted the first study to determine the diagnostic potential of the CD14++CD16+ intermediate monocytes as compared to the pro-angiogenic subset of CD14++CD16+TIE2+ TIE2-expressing monocytes (TEMs) in cancer. These monocyte populations were investigated by flow cytometry in healthy volunteers (N = 32) and in colorectal carcinoma patients with localized (N = 24) or metastatic (N = 37) disease. We further determined blood levels of cytokines associated with monocyte regulation. The results revealed the intermediate monocyte subset to be significantly elevated in colorectal cancer patients and to show the highest frequencies in localized disease. Multivariate regression analysis identified intermediate monocytes as a significant independent variable in cancer prediction. With a cut-off value at 0.37% (intermediate monocytes of total leukocytes) the diagnostic sensitivity and specificity ranged at 69% and 81%, respectively. In contrast, TEM levels were elevated in localized cancer but did not differ significantly between groups and none of the cytokines correlated with monocyte subpopulations. Of interest, in vitro analyses supported the observation that intermediate monocytes were more potently induced by primary as opposed to metastatic cancer cells which may relate to the immunosuppressive milieu established in the advanced stage of metastatic disease. In conclusion, intermediate monocytes as compared to TIE2-expressing monocytes are a more sensitive diagnostic indicator of colorectal cancer.


Assuntos
Neoplasias Colorretais/diagnóstico , Monócitos/metabolismo , Linhagem Celular Tumoral , Citocinas/sangue , Citometria de Fluxo , Humanos , Receptores de Lipopolissacarídeos/metabolismo , Valor Preditivo dos Testes , Receptor TIE-2/metabolismo , Receptores de IgG/metabolismo , Análise de Regressão , Sensibilidade e Especificidade
16.
Neoplasia ; 13(10): 980-90, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22028623

RESUMO

BACKGROUND: Circulating endothelial cells (CECs) have been proposed to predict patient response to antiangiogenic cancer therapy. However, contradictory reports and inconsistency in the phenotypic identification of CECs have led us to compare three cell populations with partially overlapping phenotype in cancer patients receiving chemotherapy and the antiangiogenic agent bevacizumab. METHODS: Patients (n = 20) with locally advanced pancreatic cancer were monitored during 16 weeks of neoadjuvant treatment with gemcitabine and bevacizumab. Detection of circulating cell populations was based on the marker combination CD45, CD31, and CD146; levels of viable and dead (7-aminoactinomycin D-positive) cells were evaluated by flow cytometry in 2-week intervals. RESULTS: We were able to discriminate and concomitantly monitor three cell populations elevated in cancer patients. Whereas CECs were defined as CD45(-) CD31(+) CD146(+), the distinct populations of CD45(-) CD31(-) CD146(+) and CD45(-) CD31(high) CD146(-) cells were partly positive for CD3 and CD41, respectively. CECs and CD45(-) CD31(-) CD146(+) cells increased during therapy; the rise in dead cells was positively correlated with patient response or survival. Conversely, CD45(-) CD31(high) CD146(-) cells decreased in neoadjuvant treatment. A highly significant correlation was established for improved patient response and a minor decrease in viable cell counts. CONCLUSIONS: Flow cytometric CEC analysis based on CD45, CD31, and CD146 requires careful discrimination between blood cell populations with overlapping phenotype showing hallmarks of activated T cells and large platelets. However, these three cell populations show distinct regulation during cancer therapy, and their concomitant analysis may offer extended prognostic and predictive information.


Assuntos
Antineoplásicos/uso terapêutico , Células Endoteliais/efeitos dos fármacos , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/tratamento farmacológico , Adulto , Idoso , Anticorpos Monoclonais Humanizados/administração & dosagem , Antígenos CD34/sangue , Bevacizumab , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Antígeno CD146/sangue , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Esquema de Medicação , Células Endoteliais/metabolismo , Feminino , Citometria de Fluxo , Humanos , Imunofenotipagem , Antígenos Comuns de Leucócito/sangue , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Neoplasias Pancreáticas/patologia , Molécula-1 de Adesão Celular Endotelial a Plaquetas/sangue , Prognóstico , Análise de Regressão , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Resultado do Tratamento , Gencitabina
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