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1.
J Magn Reson ; 305: 219-231, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31319283

RESUMEN

We present a suite of two-receiver solid-state NMR experiments for backbone and side chain resonance assignment. The experiments rely on either dipolar coupling or scalar coupling for polarization transfer and are devised to acquire a 1H-detected 3D experiment AND a nested 13C-detected 2D from a shared excitation pulse. In order to compensate for the lower sensitivity of detection on 13C nucleus, 2D rows are signal averaged during 3D planes. The 3D dual receiver experiments do not suffer from any appreciable signal loss compared to their single receiver versions and require no extra optimization. The resulting data is higher in information content with no additional experiment time. The approach is expected to become widespread as multiple receivers become standard for new NMR spectrometers.


Asunto(s)
Resonancia Magnética Nuclear Biomolecular/métodos , Proteínas/química , Isótopos de Carbono , Imagenología Tridimensional , Conformación Proteica
2.
Homo ; 69(1-2): 43-49, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29747907

RESUMEN

Common practice in field hockey requires athletes to adopt a semi-crouched posture, so players have a greater risk of musculoskeletal disorders than non-athletes. The aim of the present study was to assess how field hockey determines asymmetry in morphological and functional characteristics of the body by comparing athletes to control participants. The sample consisted of 15 male field hockey players from the Polish Youth National Team and 14 male university students. Antimeric differences in the chosen variables between body sub-regions were assessed. All morphological characteristics (bone mineral density, fat mass, and lean mass) were estimated using a dual energy X-ray absorptiometry. Additionally, the range of motion in transverse and frontal planes of the cervical, thoracic and lumbar spine was measured by using an electrogoniometric system. The results showed that the values of all morphological characteristics were higher in the left body segments, both in athletes and controls. However, the differences between sides were much more pronounced in the field hockey players. With regard to functional traits, higher values were obtained for the right body side in athletes but for the left side of the body among the controls. The difference between right and left side bending increased from the cervical spine (2.7%) through thoracic spine (7.8%) to lumbar spine (16.5%) in athletes. Rotational asymmetry in the thoracic spine was the largest in both groups. These findings indicate that it is important to monitor all athletes to prevent injury and health problems connected with strong morphological asymmetry.


Asunto(s)
Hockey/fisiología , Rendimiento Atlético/fisiología , Fenómenos Biomecánicos , Densidad Ósea/fisiología , Estudios de Casos y Controles , Lateralidad Funcional/fisiología , Fuerza de la Mano/fisiología , Humanos , Masculino , Proyectos Piloto , Polonia , Postura/fisiología , Adulto Joven
3.
Rev Sci Instrum ; 86(7): 073702, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26233391

RESUMEN

Ultrafast electron probes are powerful tools, complementary to x-ray free-electron lasers, used to study structural dynamics in material, chemical, and biological sciences. High brightness, relativistic electron beams with femtosecond pulse duration can resolve details of the dynamic processes on atomic time and length scales. SLAC National Accelerator Laboratory recently launched the Ultrafast Electron Diffraction (UED) and microscopy Initiative aiming at developing the next generation ultrafast electron scattering instruments. As the first stage of the Initiative, a mega-electron-volt (MeV) UED system has been constructed and commissioned to serve ultrafast science experiments and instrumentation development. The system operates at 120-Hz repetition rate with outstanding performance. In this paper, we report on the SLAC MeV UED system and its performance, including the reciprocal space resolution, temporal resolution, and machine stability.

4.
Thorac Cardiovasc Surg ; 62(5): 380-92, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24995534

RESUMEN

On the basis of a voluntary registry of the German Society for Thoracic and Cardiovascular Surgery (GSTCVS), data of all cardiac surgical procedures performed in 79 German cardiac surgical units during the year 2013 are presented. In 2013, a total of 99,128 cardiac surgical procedures (implantable cardioverter defibrillator [ICD] and pacemaker procedures excluded) were submitted to the registry. More than 13.8% of the patients were older than 80 years, which remains equal in comparison to the previous year. In-hospital mortality in 40,410 isolated coronary artery bypass grafting procedures (84.5% on-pump and 15.5% off-pump) was 2.9%. In 29,672 isolated valve procedures (including 7,722 catheter-based procedures), an in-hospital mortality of 4.7% was observed. This long-lasting registry of the GSTCVS will continue to be an important tool for quality control and voluntary public reporting by illustrating current facts and developments of cardiac surgery in Germany.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos/estadística & datos numéricos , Sistema de Registros , Femenino , Alemania/epidemiología , Humanos , Masculino , Sistema de Registros/estadística & datos numéricos , Sociedades Médicas
5.
Eur J Med Res ; 15 Suppl 2: 202-5, 2010 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-21147652

RESUMEN

OBJECTIVES: Nasal septum deformation (NSD) may cause breathing dysfunction. The reason for a septal deviation is the developmental anomaly in growth of the elastic septum or its skeleton. Such a type of deviation is called physiological. Some deviations can result from the prenatal trauma. The aim of the work was the analysis of the anatomy of the nasal cavity with a special interest focused on the nasal septum and its deviation. MATERIAL AND METHODS: The nasal cavity with its bones and septum was analyzed in CT images of 105 spontaneously aborted fetuses (57 males and 48 females) aged 12 and 40 weeks of gestation. We attempted to assess the morphometric development of the nasal cavity with tomographic scanning methods and to detect anatomical variations. RESULTS: In 15 (14.3%) fetuses, NSD were detected on radiological sections. The angle between the virtual line from the sphenoid sinus ostium through limen nasi and the horizontal plane was 33.6 ±2.3°, on average. CONCLUSIONS: NSD may already be found in fetuses. The observation of the nasal cavity development enables to evaluate the growth and symmetry of the nasal septum and to foretell predispositions for dysfunction in the upper respiratory tract.


Asunto(s)
Feto/diagnóstico por imagen , Tabique Nasal/anomalías , Tomografía Computarizada por Rayos X/métodos , Femenino , Humanos , Masculino , Tabique Nasal/diagnóstico por imagen
6.
Biomaterials ; 27(16): 3084-95, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16460796

RESUMEN

A dextran-modified poly(vinyl amine) comb-like surfactant polymer, poly(N-vinyl dextran aldonamide-co-N-vinyl hexanamide), that can surface-adsorb on hydrophobic polymeric substrates, was designed to improve the interfacial blood-compatibility of polymeric biomaterials. Medical-grade polycarbonate was selected as a model substrate because of its extensive use in blood-contacting biomedical devices like hemodialyzers, blood pumps and oxygenators. The surfactant polymer was physisorbed from aqueous solution onto the polycarbonate substrate. The surfactant coating was stable under dynamic shear conditions in whole blood, as confirmed by fluorescence microscopy and total internal reflection fluorescence (TIRF) experiments with fluorescein-labeled surfactant polymer. The coated disks and uncoated control disks were exposed to platelet-rich plasma (PRP) and whole human blood in a rotating disk system (RDS) to study platelet-adhesion under dynamic shear stress environments. Adhered platelets were stained with fluorescein isothiocyante (FITC)-tagged anti-CD41a monoclonal antibody and imaged by epifluorescence microscopy. Complimentary images were obtained by phase-contrast microscopy. Platelet adhesion on the surfactant-coated disks was reduced by approximately 90%, compared with uncoated disks. The images also showed a concomitant reduction in platelet-derived microparticles on surfactant-coated disks, compared with uncoated disks. The results suggest potential application of carbohydrate-modified surfactant polymers as a glycocalyx-mimetic non-thrombogenic interfacial coating for blood-contacting biomaterials.


Asunto(s)
Materiales Biomiméticos/farmacología , Dextranos/química , Glicocálix/química , Adhesividad Plaquetaria/efectos de los fármacos , Cemento de Policarboxilato/química , Polivinilos/química , Adulto , Materiales Biomiméticos/química , Plaquetas/citología , Plaquetas/efectos de los fármacos , Plaquetas/fisiología , Humanos , Microscopía Fluorescente , Microscopía de Contraste de Fase , Estructura Molecular , Polímeros/química , Resistencia al Corte , Propiedades de Superficie , Tensoactivos/química , Tensoactivos/farmacología
7.
J Physiol Pharmacol ; 57 Suppl 11: 79-92, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17244940

RESUMEN

Cardiovascular diseases are the most frequent causes of morbidity and mortality around the world. However, during last decades, an improvement was made in diagnosis and therapy of cardiovascular diseases, there was still a need for better understanding of their pathophysiology. Among neurohormonal systems, SNS plays a central role in cardiovascular regulation in both health and disease. Involvement of SNS in pathogenesis of hypertension, coronary artery disease or heart failure is well known and proved. Methods such as microneurography, direct catecholamine measurements, heart rate variability or baroreflex sensitivity assessment allowed studying sympathetic activity and its influence on cardiovascular disorders. Although introduced into scientific practice methods of SNS evaluation are not commonly used in the clinic. However, two of the methods: analysis of heart rate variability (HRV) and baroreflex sensitivity (BRS) were recommended as the diagnostic tools and can be found in clinical guidelines as basic assessment methods.


Asunto(s)
Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/fisiopatología , Sistema Nervioso Simpático/fisiopatología , Barorreflejo , Presión Sanguínea , Enfermedad Coronaria/fisiopatología , Neuropatías Diabéticas/fisiopatología , Insuficiencia Cardíaca/fisiopatología , Frecuencia Cardíaca , Humanos , Hipertensión/fisiopatología , Norepinefrina/sangre , Norepinefrina/orina
8.
Phys Rev Lett ; 94(12): 125510, 2005 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-15903937

RESUMEN

We report a brittle Mg-based bulk metallic glass which approaches the ideal brittle behavior. However, a dimple structure is observed at the fracture surface by high resolution scanning electron microscopy, indicating some type of "ductile" fracture mechanism in this very brittle glass. We also show, from the available data, a clear correlation between the fracture toughness and plastic process zone size for various glasses. The results indicate that the fracture in brittle metallic glassy materials might also proceed through the local softening mechanism but at different length scales.

9.
Pol Merkur Lekarski ; 10(55): 19-20, 2001 Jan.
Artículo en Polaco | MEDLINE | ID: mdl-11320544

RESUMEN

The aim of the study was to evaluate the influence of chronic cholecystitis on haemostasis. The study was conducted on 48 patients suffering from chronic cholecystolithiasis admitted for cholecystectomy to the Department of Surgery Regional Hospital in Bialystok. The control group consisted of 25 healthy subjects in this same age range. As a result of the study we found out that patients with chronic cholecystitis had hypercoagulability characterised by increase plasma concentrations of the sensitive markers of haemostasis: prothrombin fragments (F1 + 2), thrombin/antithrombin complex (TAT) and D-dimer.


Asunto(s)
Colelitiasis/complicaciones , Trombofilia/etiología , Adulto , Anciano , Antitrombina III , Biomarcadores/sangre , Colelitiasis/sangre , Femenino , Productos de Degradación de Fibrina-Fibrinógeno/análisis , Hemostasis/fisiología , Humanos , Masculino , Persona de Mediana Edad , Fragmentos de Péptidos/sangre , Péptido Hidrolasas/sangre , Precursores de Proteínas/sangre , Protrombina , Trombofilia/sangre , Trombofilia/diagnóstico
10.
Med Sci Monit ; 7(2): 312-5, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11257742

RESUMEN

The study was concerned with verification of the selection of reference points used for knee joint mobility range goniometry. The verification was based on photometric and electrogoniometric methods of femorotibial angle measurements. The material for measurements were three knee joint preparations. The obtained data were subjected to descriptive analysis; photographic documentation of geometric relations between the reference points was also prepared. Considerable divergence of measurement results was observed with respect to the actual knee joint flexion angle, amounting even to 16 degrees. The differences are due to the selection of anatomic landmarks, and depend in particular on the distance of the point to which the goniometer axis is applied from the approximate location of the mechanical joint axis. The corrections of knee joint flexion angle measurements were also estimated on the basis of data obtained from the photographs and the derived mathematical formula.


Asunto(s)
Articulación de la Rodilla/fisiología , Rango del Movimiento Articular , Humanos , Articulación de la Rodilla/anatomía & histología
11.
Phys Rev Lett ; 85(17): 3564-7, 2000 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-11030951

RESUMEN

The notion of isolated horizons is extended to allow for distortion and rotation. Space-times containing a black hole, itself in equilibrium but possibly surrounded by radiation, satisfy these conditions. The framework has three types of applications: (i) it provides new tools to extract physics from strong field geometry; (ii) it leads to a generalization of the zeroth and first laws of black hole mechanics and sheds new light on the "origin" of the first law; and (iii) it serves as a point of departure for black hole entropy calculations in nonperturbative quantum gravity.

13.
Regul Pept ; 75-76: 239-45, 1998 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-9802415

RESUMEN

Some evidences indicate that the female sex hormones protect against the development of cardiovascular diseases. Modulation of sympathetic activity may be one of the possibilities. We investigated the influence of treadmill stress on blood pressure (BP) and plasma neuropeptide Y (NPY), norepinephrine (NE) and epinephrine (E) concentrations in 11 normotensive, menstruating women in the follicular (HWf) and luteal (HWl) phases and in eight ovariectomized women, before (OVX) and after estrogen supplementation (OVXe). Both at rest and during exercise there were no differences in BP between HWf and HWl and between OVX and OVXe. During stress BP was significantly lower in HWf and HWl than in OVX but not in OVXe. NPY did not differ significantly between the groups of women either at rest or during activity. We did not observe differences in resting and stimulated NE and E between HWf and HWl and between OVX and OVXe. Neither resting nor activated NE and E differed between the groups, except higher stimulated NE in OVX than in HWf. These results suggest that the female sex hormones may modulate the BP response to dynamic exercise. Our data support evidence that this influence may be exerted by circulating catecholamines and not by NPY.


Asunto(s)
Presión Sanguínea/fisiología , Epinefrina/sangre , Ejercicio Físico/fisiología , Hormonas Esteroides Gonadales/fisiología , Neuropéptido Y/sangre , Norepinefrina/sangre , Adulto , Enfermedades Cardiovasculares/etiología , Enfermedades Cardiovasculares/fisiopatología , Enfermedades Cardiovasculares/prevención & control , Terapia de Reemplazo de Estrógeno , Femenino , Humanos , Ciclo Menstrual/sangre , Ciclo Menstrual/fisiología , Ovariectomía , Estrés Fisiológico/sangre , Estrés Fisiológico/fisiopatología
14.
J Ambul Care Manage ; 21(1): 12-23, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10181336

RESUMEN

The ability to link pharmacy claims and clinical laboratory result databases in a managed care setting holds great promise as an outcomes management tool. The authors have created a powerful disease management capability that generates dynamic, disease-specific reports containing actionable, provider-patient-level laboratory and pharmacy information. This system is used to send reports to primary care physicians in an independent practice association (IPA)-model managed care setting to improve the care of patients with diabetes mellitus. This systematic feedback methodology can augment physician decision-making behavior, promote compliance with national guidelines, and measure improvement in plan-level, population-based outcomes over time.


Asunto(s)
Diabetes Mellitus , Manejo de la Enfermedad , Asociaciones de Práctica Independiente/normas , Auditoría Médica/métodos , Sistemas de Información en Laboratorio Clínico , Sistemas de Información en Farmacia Clínica , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/tratamiento farmacológico , Retroalimentación , Femenino , Adhesión a Directriz , Humanos , Asociaciones de Práctica Independiente/organización & administración , Masculino , Registro Médico Coordinado , Michigan , Atención Primaria de Salud/normas , Integración de Sistemas
15.
Blood Press ; 6(4): 203-8, 1997 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9296306

RESUMEN

Hemorrheological and humoral abnormalities and excessive platelet activity can predict the development of cardiovascular complications in patients with essential hypertension. A study was conducted to assess the influence of gender on these factors and the interrelations between changes in hemorrheology and the sympatho-adrenal system in 54 patients (18 women, 36 men) with essential hypertension (aged 39.6 +/- 9.7 years) and 25 healthy volunteers (10 women, 15 men; aged 36.0 +/- 7.2 years). A decrease in erythrocyte deformability (p < 0.01) was found in the hypertensive men compared with the hypertensive women. Hematocrit (p < 0.01), blood viscosity at the shear rates of 0.3 s-1 (p < 0.01) and 6 s-1 (p < 0.01), plasma viscosity (p < 0.01), erythrocyte aggregation (p < 0.01), and neuropeptide Y (p < 0.02) concentrations were higher in the hypertensive men than in the hypertensive women. A positive correlation between blood fibrinogen and serotonin was found in the pooled hypertensive group and in the hypertensive men (p < 0.01) and between blood viscosity (shear rate 6 s-1) and neuropeptide Y in the pooled hypertensive group (p < 0.01). Neuropeptide Y correlated with filtration time of 1 mL blood in the hypertensive men (p < 0.05) and in the pooled normotensive group (p < 0.01) and with beta-thromboglobulin in the hypertensive women (p < 0.001). A positive correlation was also found in the hypertensive men between erythrocyte and platelet aggregation (p < 0.01) and between beta-thromboglobulin and adrenaline (p < 0.01). Hemorrheological and humoral abnormalities are more pronounced in men than in women with essential hypertension and may contribute to the increased incidence of cardiovascular events in men.


Asunto(s)
Epinefrina/sangre , Hipertensión/sangre , Neuropéptido Y/sangre , Norepinefrina/sangre , Serotonina/sangre , Adulto , Agregación Eritrocitaria , Femenino , Fibrinógeno/metabolismo , Hematócrito , Humanos , Masculino , Persona de Mediana Edad , Agregación Plaquetaria , Reología , Factores Sexuales , beta-Tromboglobulina/metabolismo
16.
J Hum Hypertens ; 11(6): 373-8, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9249232

RESUMEN

The plasma aldosterone to renin activity ratio (A/PRA) was assessed retrospectively in 103 patients with primary aldosteronism including 74 patients with surgically proven adrenal cortical adenoma (APA) and 29 patients with idiopathic adrenal cortical hyperplasia (IHA). The results were compared with those obtained in 31 patients with essential hypertension (EH) and 45 healthy normotensive controls. The upper limit of normal A/PRA ratio, as obtained in the controls was 17.8. This value was exceeded in 89% of patients with APA; postoperatively it decreased in 97% of the APA group, and returned to normal in 81%. In the IHA group the A/PRA was elevated in 70% of patients. The normal ratios in patients with primary aldosteronism were associated with unsuppressed plasma renin activity (PRA). Although the mean values of the A/PRA ratio differed significantly between the groups, complete separation was not obtained. The serum potassium level at time of testing did not influence the diagnostic value of the A/PRA ratio, although an inverse correlation between serum potassium and the A/PRA ratio was found in the patients with APA. This study supports the high sensitivity of the A/PRA ratio in diagnosis of primary aldosteronism, however, a single determination with a normal result may not be sufficient for exclusion of the disease.


Asunto(s)
Aldosterona/sangre , Hiperaldosteronismo/sangre , Renina/sangre , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Potasio/sangre , Estudios Retrospectivos
18.
Z Morphol Anthropol ; 81(2): 189-203, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9270336

RESUMEN

Studies on the formation of morphological traits of the quadriceps femoris muscle were carried out on the material of 138 human fetuses (70 males and 68 females), 9-36 weeks old, and 50 adults (33 male, and 17 female). Some intermediary conclusions were drawn for probable changes occurring in the morphological formation of the muscle after birth by comparing proportions of the muscle at the fetal stage with its form in adults. In this research, anthropometric methods and statistical analysis of results have been applied. The analysis of the results in the fetal group has shown that all metrical characteristics of the muscle reach their maximum values at the end of the investigated ontogenetic period. This is, naturally, a consequence of the development and growth of all fetal body measures, including an elongation of the thigh. Yet, the development of the individual muscle characteristics is not regular and although the trend of this growth is similar, its extent varies, and differs slightly in the two sexual groups. A comparison of the values of muscle indices for 9 month old fetuses with the same indices for adults shows that the relative dimensions of all investigated muscular characteristics decrease during the post-natal period except the relative length of the tendon.


Asunto(s)
Envejecimiento , Desarrollo Embrionario y Fetal , Músculo Esquelético/anatomía & histología , Adulto , Femenino , Edad Gestacional , Humanos , Pierna , Masculino , Desarrollo de Músculos , Músculo Esquelético/embriología , Músculo Esquelético/crecimiento & desarrollo , Caracteres Sexuales
20.
Pol Arch Med Wewn ; 95(3): 190-7, 1996 Mar.
Artículo en Polaco | MEDLINE | ID: mdl-8755848

RESUMEN

Investigated group consisted of 28 patients (21 female and 7 male) with pheochromocytoma in mean age of 39.9 +/- 13 years, while control group comprised 25 healthy volunteers in mean age 36.0 +/- 7.2 years. Following parameters were determined: plasma and blood viscosity, erythrocyte and platelets aggregation, erythrocyte deformability, hematocrit, beta-thromboglobulin plasma concentration, plasma fibrinogen concentration, lipids concentration, noradrenaline, adrenaline, serotonin, neuropeptide Y plasma concentrations. Plasma fibrinogen and beta-thromboglobulin were increased in pheochromocytoma before surgery after pharmacological treatment and also after excision of the tumor. Whereas altered erythrocyte deformability before any treatment, only. Plasma neuropeptide Y concentration was higher in pheochromocytoma before surgery and after pharmacological treatment. There was no correlation between plasma catecholamines, plasma fibrinogen, beta-thromboglobulin, and erythrocyte deformability. Our results suggest that rheological abnormalities observed in patients with pheochromocytoma may contribute to vascular complications in this subjects. Sympathetic nervous system seems to influence indirectly observed rheological abnormalities.


Asunto(s)
Feocromocitoma/fisiopatología , Adulto , Deformación Eritrocítica , Femenino , Fibrinógeno/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Neuropéptido Y/sangre , Feocromocitoma/terapia , Reología , Sistema Nervioso Simpático/fisiopatología , beta-Tromboglobulina/metabolismo
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