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1.
Artigo em Inglês | MEDLINE | ID: mdl-38489170

RESUMO

BACKGROUND: The functioning of the thyroid gland is a multi-component process that in some conditions may undergo alterations. The thyroid gland is part of the endocrine system that produces the iodine-containing hormones thyroxine and triiodothyronine. Thyroid hormones, control metabolism and energy, growth processes, maturation of tissues and organs, regulation of blood flow, and, therefore, providing vital functions of the body. The role of thyroid hormones in the regulation of blood flow is determined by the intensity of their production and the quantity in the blood. Presumably, in case of oncological and non-oncological diseases of the thyroid gland, the fluidity of the blood, which depends on the rheological properties, will be different. OBJECTIVE: Our aim was investigating rheological characteristics for studying of changes of rheology in patients with thyrotoxicosis, with benign tumor pathology of the thyroid gland, with thyroid cancer and finding possible diagnostic markers for differentiating benign and malignant thyroid tumors. METHODS: In this regard, we examined, using modern methods accepted in clinical practice, a standard list of recommended diagnostic tests in the group of patients (thyrotoxicosis: n = 25; benign tumor: n = 47), thyroid cancer: n = 35) and control group (n = 15), and with new original methods, parameters that describe the rheological properties of the blood, such as blood rheological index, volume, thickness, surface area of erythrocytes, erythrocyte aggregation index, deformation index, plasma viscosity, hematocrits. RESULTS: Against the background of relative changes in the studied values, it is necessary to pay attention to the fact that erythrocyte aggregation in patients with a benign form and control, as well as in patients with a malignant form and control, differ significantly from each other, in addition, there is a significant difference between aggregation in the group of patients with benign and control aggregation. malignant forms of the disease. It is significant that aggregability differs in patients with thyrotoxicosis and in controls. This indicates that erythrocyte aggregation is particularly informative. The blood rheological index most clearly demonstrated the difference between benign and malignant forms of the disease. Significantly changed compared to control in various forms of thyroid diseases. CONCLUSION: Additional diagnostic markers for differentiating benign and malignant thyroid tumors may be consideredeerythrocyte aggregation index and blood rheological index.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38363605

RESUMO

BACKGROUND: The triad "insulin resistance, prediabetes, diabetes" is three independent neologies with characteristic features and development. In addition, each are characterized by progression and the possibility of transition from one form to other. Due to the fact that diabetes is one of the common diseases associated with high rates of disability, it is necessary to improve diagnostic methods and educational regimens for successful prevention and treatment of the disease. OBJECTIVE: We investigated Band 3 protein (B3p) level, osmotic resistance of erythrocytes, the total antioxidant activity (TAA) of blood serum, level of HbA1 in group patients with insulin resistance (IR), prediabetes, and Type 2 Diabetes Mellitus (T2DM) and comparative with health control group. METHODS: We used original, accurate research methods that measure the essence of the studied quantities. RESULTS: Disruptions of glucose and insulin homeostasis ay lead to the initiation of oxidative stress (in our study demonstrated by a decrease of TAA of blood serum) increased redox-sensitive PTP activity and aberrant band 3 phosphorylation, potentially leading to reduced erythrocyte deformability. At the same time glycation of Hb during T2DM may affect its cross-link with membrane proteins, in particular with B3p, and although appears to limit its cross-linking and decrease its clusterization ability, induces alterations in the cytoskeletal matrix, and thereby decrease erythrocytes' osmotic resistance making them more susceptible to hemolysis. CONCLUSIONS: The osmotic resistance of the erythrocytes can be used as a sensitive marker for the detection of the early stages of hyperglycemia (prediabetes). This set of clinical trials will make it possible to identify diseases that make up the triad at an early stage. Early detection of disorders and continued research in this direction will help in the development of a diagnostic scheme for the prevention of such patients. Based on our data, research into anti-oxidation drugs is very important. With the help of the array of studies described in the article and antioxidant treatment, the likelihood of successful treatment will increase.

3.
Clin Hemorheol Microcirc ; 86(1-2): 29-50, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38363606

RESUMO

 This review spans a wide arc from the first observations of the early anatomists to the present day. William Harvey was the first to describe the heart as the centre of the large and small circulatory system. He thus replaced the previously valid system of Galenos, It was Marcello Malpighi who first described that the capillary system connects the arteries with the veins. In 1688 Antoni van Leeuwenhoek (1632-1686) confirmed these results with a paper on capillary perfusion in the caudal fin of the glass eel. It was then Hermann Boerhave (1668-1738, Leiden) who was the first to carry out microcirculation tests on patients. He studied the microcirculation in the human bulbar conjunctiva. Even today, microcirculation studies in the conjunctiva bulbi of patients are carried out today. Until 1831, it was never quite clear whether the observations reported belonged mainly to the field of microcirculation, which had not yet been defined. This was done in Great Britain by Marshall Hall (1790-1857). Technical Improvements allowed increasingly sophisticated studies of the morphological structure of the terminal vasculature. According to Gustav Ricker (1870-1948, Vienna), the terminal vasculature comprises the functional unit of the smallest arteries, arterioles, capillaries and venules. In 1921 it was still thought that the blood circulation was the sole response to the pumping action of the heart. Even the classic work by Bayliss on the myogenic hypothesis (later referred to as "blood flow autoregulation") initially received little attention. More strikingly, even the findings of August Krogh, for which he received the Nobel Prize in Medicine in 1920 (for his discovery of the mechanisms of capillary motor regulation), were ignored. During an outstanding autoregulation symposium held in 1963 a broad consensus was reached on active and passive mechanisms, which is more or less valid till today. The mechanisms of regulation of capillary blood flow are now largely understood, although not completely resolved. The development of video systems with recording capability and automated off-line recording of capillary erythrocyte velocities allowed the application of morphological and dynamic studies of cutaneous capillaries in humans. These reopened the field of physiological or pathophysiological questions again for many groups worldwide. Since 1955, many publications on "microcirculation (5423)" and "capillary microscopy (2195)" have been listed in pubmed.


Assuntos
Capilares , Eritrócitos , Humanos , Microcirculação/fisiologia
4.
Clin Hemorheol Microcirc ; 86(1-2): 205-211, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37638424

RESUMO

The growth of cyanobacteria can vary considerably depending on the ambient temperature. Since the optimal growth temperature for Arthrospira platensis (strain SAG21.99) is not yet known, this was investigated in the present study. The study revealed that a process temperature of 30 °C seems to be optimal for the Arthrospira strain SAG21.99 cultivation in terms of a maximum biomass productivity. This was also true for the phycocyanin content which was at 30 °C significantly higher than at 20 or 40 °C.


Assuntos
Spirulina , Temperatura
5.
Clin Hemorheol Microcirc ; 86(1-2): 133-142, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37742633

RESUMO

AIM: First assessment of flow changes in the jugular veins using high resolution ultrasound vector flow. MATERIAL UND METHODS: 15 patients (8 males, 7 females) with an age range of 35 to 82 years (mean age 58.53±12.26 years) were examined by an experienced examiner using high power ultrasound equipment (Resona R9, Mindray) with probe technology (Mindray L9-3U Linear Array transducer, 2.5 to 9.0 MHz). This group was compared with five healthy subjects (mean age 35.4±13.79 years) as a reference. To assess flow changes, the color-coded duplex sonography and the novel vector flow technique were used. The evaluation was performed of vector morphology changes, turbulence, and wall resistance measurements. RESULTS: There were changes after acute and chronic thrombosis in 9 cases, and venous compression in 7 cases. Turbulence was measurable from 0.01 % to 64.44 %, the average turbulence was 19.73±22.06 %. Wall resistance measurement showed values from 0.01 Pa to 3.14 Pa, depending on the age of the thrombosis or compression. The reference veins showed turbulence of 0.94±1.5 % and a mean wall resistance of 0.05±0.05 Pa. There are statistically significant differences between normal and thrombotic or compressed veins in terms of maximum wall stress (p = 0.006) and mean degree of turbulence (p = 0.012), while the difference in mean wall stress is not statistically significant (p = 0.058). CONCLUSION: Despite still existing technical limitations, the combination of V-flow and wall stress measurements in jugular vein changes suggests a high diagnostic potential.


Assuntos
Veias Jugulares , Trombose , Masculino , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Adulto Jovem , Veias Jugulares/diagnóstico por imagem , Veias , Trombose/diagnóstico por imagem , Ultrassonografia Doppler Dupla
6.
Artigo em Alemão | MEDLINE | ID: mdl-37361962

RESUMO

Changes in the working environment with respect to innovative working time models are also increasingly affecting patient care. The number of physicians working part-time, for example, is continuously rising. At the same time, a general increase in chronic diseases and multimorbid conditions as well as the growing shortage of medical staff, leads to more workload and dissatisfaction among this profession. This short overview summarizes the current study situation and associated consequences regarding working hours of physicians and gives a first explorative overview of possible solutions.

7.
Clin Hemorheol Microcirc ; 84(2): 227-236, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37092219

RESUMO

 Goal of the study was the assessment of AI-assisted diagnosis of solid thyroid foci with multimodal modern ultrasound imaging. 50 patients (26-81 years, 54.7±13.1 years) were included in the study. Multimodal ultrasound imaging by means of B-mode with linear probe (4-12 MHz) with option of automated documentation of findings by means of AI, with supplementary Ultra MicroAngiography (UMA) was used. Macrovascularisation was assessed by dynamic contrast ultrasonography (CEUS) with parametric evaluation and perfusion analysis, and microvascularization was assessed by combined strain and shear wave elastography on a novel high-performance ultrasound system (Resona R9/Mindray) by an experienced examiner with independent reading. The evaluation was performed according to TI-RADS III-V.The volume of the thyroid lobes on both sides averaged 39 ml±5 ml (27 to 69 ml). The 13 cases of histologically confirmed thyroid carcinomas (8 papillary, 2 medullary, 2 microfollicular, 1 anaplastic CA) with a mean size of 15 mm±6 mm (9-21 mm) were correctly evaluated by TI-RADS V on the basis of irregular shape, induration > 2.5 m/s or > 30kPA and striking wash-out kinetics. Tumor lymph nodes could only be correctly detected preoperatively in one case of medullary carcinoma according to the surgical findings, based on irregular vascularization with UMA in roundish shape with cortex > 4 mm, transverse diameter up to 11 mm. In 25 cases of inhomogeneous nodular goiter an evaluation with TI-RADS III was performed in 31 cases, in 4 cases with incomplete marginal contour, partial marginal vascularization with UMA and partial wash out with indurations up to 2.5 m/s 30 kPA an evaluation with TI-RADS IV and surgical excision for nodular goiter. In 12 cases regressive nodular changes without relevant malignancy criteria resulted in nodular goiter, with focal changes up to 1.5 cm in diameter, classified as requiring control with TI-RADS III. There were no relevant changes in findings in the controls after 6 months. From the AI tool, the 20/25 goiter nodes were assessed as TI-RADS III, 7/12 adenomas, 5 goiter nodes, and 5 adenomas as TI-RADS IV, 5/13 carcinomas as TI-RADS IV, and 8/13 carcinomas as TI-RADS V.Multimodal ultrasound diagnostics supported by AI has a high diagnostic potential for the evaluation of solid thyroid lesions and standardizes the reporting with digital representative image documentation. CEUS perfusion and modern elastography techniques allow targeted follow-up of TI-RADS III findings.


Assuntos
Carcinoma Neuroendócrino , Técnicas de Imagem por Elasticidade , Bócio Nodular , Neoplasias da Glândula Tireoide , Nódulo da Glândula Tireoide , Humanos , Inteligência Artificial , Técnicas de Imagem por Elasticidade/métodos , Imagem Multimodal , Perfusão , Estudos Retrospectivos , Sensibilidade e Especificidade , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/patologia , Nódulo da Glândula Tireoide/patologia , Ultrassonografia/métodos , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais
8.
Clin Hemorheol Microcirc ; 83(2): 181-193, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36776044

RESUMO

Current ultrasound multifrequency probes allow both improved detail resolution and depth of penetration when examining the liver. Also, new developments in vascular diagnostics, elastography with fibrosis assessment, evaluation of possible steatosis, and parametric and time intensity curve (TIC) analysis of dynamic microvascularization of the liver with contrast-enhanced ultrasound sonography (CEUS) complement ultrasound-guided diagnostics. State-of-the-art high-resolution technology includes a high frame rate (HiFR) mode for CEUS, fast shear wave measurements with the sound touch quantify (STQ) mode, artifact-free flow detection using HR flow and glazing flow in combination with a special flow-adapted imaging (Ultra Micro Angiography, UMA) and additionally different assessments of possible fatty liver (UltraSound ATtenuation Imaging Technology, USAT). In 50 cases with focal liver lesions, a multimodal liver diagnosis was performed with a still new high-performance ultrasound system as part of the clarification of questions from the university liver consultation and tumor outpatient clinic.


Assuntos
Neoplasias Hepáticas , Humanos , Neoplasias Hepáticas/patologia , Meios de Contraste , Ultrassonografia/métodos , Fígado/diagnóstico por imagem , Perfusão , Fibrose
9.
BMC Health Serv Res ; 23(1): 157, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36793035

RESUMO

BACKGROUND: According to new estimates, the health care sector will suffer a shortage of physicians in primary and specialty care. In this context, work engagement and burnout are two constructs that have gained attention recently. The aim of this study was to investigate how these constructs are related to work hour preference. METHOD: The present study was based on the baseline survey of the long-term study of physicians with different specialties, in which 1,001 physicians took part (response rate: 33.4%). Burnout was measured using the Copenhagen Burnout Inventory adapted for health care professionals; work engagement was assessed using the Utrecht Work Engagement scale. Data analyses included regression and mediation models. RESULTS: Overall, 297 out of 725 physicians were planning to cut down work hours. Several reasons - such as burnout - are discussed. According to multiple regression analyses desire to work less hours was significantly linked to all three dimensions of burnout (p < 0.001), as well as work engagement (p = 0.001). In addition, work engagement significantly mediated the relationship between the burnout dimensions on work hour reduction (patient-related: b = - 0.135, p < 0.001; work-related: b = - 0.190, p < 0.001; personal: b = - 0.133, p < 0.001 ). DISCUSSION: Physicians tending to reduce work hours exhibited different levels of work engagement as well as burnout (personal, patient- and work-related). Moreover, work engagement influenced the relationship between burnout and work hour reduction. Therefore, interventions that increase work engagement may positively impact negative effects of burnout on work hour changes.


Assuntos
Esgotamento Profissional , Médicos , Humanos , Engajamento no Trabalho , Esgotamento Profissional/epidemiologia , Pessoal de Saúde , Inquéritos e Questionários , Satisfação no Emprego
10.
Artigo em Inglês | MEDLINE | ID: mdl-36502310

RESUMO

 Iodinated contrast media (ICM) are widely used for diagnostic and interventional procedures in radiology and cardiology. Ideally, they should not interact with blood cells or vascular wall cells to avoid deteriorations of the blood circulation. However, it is well known that ICM can affect erythrocytes as well as endothelial cells which consequently might perturb especially the microcirculation. In former studies the influence of two ICM (iodixanol versus iopromide) on the vascular system, the development of blood stasis, on changes in renal resistive index (RRI) and vascular diameters, and on the post-mortem distribution of iodine as marker for ICM in the explanted kidneys was examined. The modus of ICM application into the supra-renal aorta followed the regime in interventional cardiology, so that 10 bolus injections were administered at steady intervals (iopromide 4,32 ml / iodixanol 5 ml) accompanied by infusion of 500 ml isotonic NaCl-solution.In the present study, the post-mortem X-ray analysis revealed that there were no differences in iodine content in the regions of the mid-cortex and the medullo-pelvic transition zone of the kidneys after application of both ICM. Remarkable differences, however, were found in the region of the capsule-near cortex, where the application of iopromide led to a significantly lower iodine content in the microcirculation. This is in good agreement with former studies, in which a maldistribution in this area, presumably due to a decrease in arteriolar inflow as a result of stasis/occlusion was shown.

12.
BMC Health Serv Res ; 22(1): 1082, 2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-36002851

RESUMO

BACKGROUND: Changes in everyday work with regard to working time models have reached the medical profession. The number of physicians working part-time is steadily increasing. At the same time, however, the population's need for care is also rising. This can reinforce the impending shortage of doctors in the future. The aim was to investigate differences in work-privacy conflict and burnout among physicians working full-time or part-time. METHOD: The present study includes data from a baseline survey of the long-term study of physicians with different medical backgrounds. The analysis focused on a sub-sample of 598 physicians (not self-employed). The two main outcomes under investigation-burnout and work-privacy conflict-were measured using the Copenhagen Burnout Inventory adapted for health care professionals, as well as the associated subscale of the Copenhagen Psychosocial Questionnaire (COPSOQ). Data analyses included descriptive statistics followed by regression models. RESULTS: Descriptive analyses show, that 31.8% of physicians are working part-time, whereas 68.2% are working full-time. The part-time subsample is significantly older, and female physicians are more likely to work part-time. With regard to workload and work-privacy conflict, significant differences between part-time and full-time physicians were only observed in terms of work-privacy-conflict. However, regression analysis underline the importance of possible confounding variables (such as medical setting) within the relationship between job size and job-related well-being. DISCUSSION: Differences in working hour arrangements (full-time or part-time work) are only accompanied by less work-privacy conflict. No differences with regard to burnout (patient-related, work-related or personal) could be obtained. Rather, the data suggests that other job-related variables may play a role and should be further investigated.


Assuntos
Esgotamento Profissional , Médicos , Esgotamento Profissional/epidemiologia , Esgotamento Profissional/psicologia , Feminino , Humanos , Satisfação no Emprego , Médicos/psicologia , Privacidade , Inquéritos e Questionários , Carga de Trabalho/psicologia
13.
Phys Rev Lett ; 128(20): 203401, 2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35657871

RESUMO

Reaching high densities is a key step toward cold-collision experiments with polyatomic molecules. We use a cryofuge to load up to 2×10^{7} CH_{3}F molecules into a boxlike electric trap, achieving densities up to 10^{7}/cm^{3} at temperatures around 350 mK where the elastic dipolar cross section exceeds 7×10^{-12} cm^{2}. We measure inelastic rate constants below 4×10^{-8} cm^{3}/s and control these by tuning a homogeneous electric field that covers a large fraction of the trap volume. Comparison to ab initio calculations gives excellent agreement with dipolar relaxation. Our techniques and findings are generic and immediately relevant for other cold-molecule collision experiments.

14.
Clin Hemorheol Microcirc ; 81(3): 191-203, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35275526

RESUMO

In vivo endothelialization of polymer-based cardiovascular implant materials is a promising strategy to reduce the risk of platelet adherence and the subsequent thrombus formation and implant failure. However, endothelial cells from elderly patients are likely to exhibit a senescent phenotype that may counteract endothelialization. The senescence status of cells should therefore be investigated prior to implantation of devices designed to be integrated in the blood vessel wall. Here, human umbilical vein endothelial cells (HUVEC) were cultivated up to passage (P) 4, 10 and 26/27 to determine the population doubling time and the senescence status by four different methods. Determination of the senescence-associated ß-galactosidase activity (SA-ß-Gal) was carried out by colorimetric staining and microscopy (i), as well as by photometric quantification (ii), and the expression of senescence-associated nuclear proteins p16 and p21 as well as the proliferation marker Ki67 was assessed by immunostaining (iii), and by flow cytometry (iv). The population doubling time of P27-cells was remarkably greater (103±65 h) compared to P4-cells (24±3 h) and P10-cell (37±15 h). Among the four different methods tested, the photometric SA-ß-Gal activity assay and the flow cytometric determination of p16 and Ki67 were most effective in discriminating P27-cells from P4- and P10-cells. These methods combined with functional endothelial cell analyses might aid predictions on the performance of implant endothelialization in vivo.


Assuntos
Senescência Celular , Endotélio Vascular , Células Cultivadas , Células Endoteliais da Veia Umbilical Humana , Humanos , Antígeno Ki-67
15.
Clin Hemorheol Microcirc ; 80(2): 49-59, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35001884

RESUMO

AIM: To evaluate the additive clinical value of endoluminal contrast enhanced ultrasound (CEUS) after interventional placement of drainages in abdominal fluid collections. MATERIAL/METHOD: Examination of 30 patients using a 1-6 MHz convex probe (Resona 7, Mindray) to locate the fluid collection in B-Mode. Additionally, dynamic endoluminal CEUS with 1 ml sulphur-hexafluoride microbubbles was performed to measure the extent of the percutaneously drained abscesses. Independent assessment of dynamically stored images in PACS in DICOM format. Correlation to reference imaging using computed tomography (CT). RESULTS: A total of 30 patients were examined (17 m, 19-78 years, mean 56.1 years). Drainages were positioned in the liver in 15 cases, in the pelvis after kidney transplantation in 4 cases, close to the spleen in 1 case, and in the abdomen in 10 cases. In all cases abscesses showed marginal hyperaemia with reactive septations in CEUS. The drainage position was assessed by means of B-mode in all cases first and then by CEUS. In 4 cases CEUS showed a fistula to the pleura, in 5 cases to the peritoneum, in 2 cases to the intestine, in 5 cases to the biliary tract, corresponding to the CT. In 2 cases there was a hint of an anastomotic leakage after intestinal anastomosis, which was reliably detected by CT. The drainage was removed in 11 cases within a period of 2 to 5 days after CEUS control, in 9 cases within a period of 5 to 10 days. Another operation was necessary in 3 cases. A new drainage was placed in 2 cases. The required amount of ultrasound contrast medium is 1 ml endoluminally diluted to 9 ml sodium chloride. CONCLUSION: CEUS facilitates the exact localization and characterization of inflammatory abdominal fluid collections. Furthermore, possible fistulas can be detected that cannot be seen with conventional ultrasound.


Assuntos
Meios de Contraste , Microbolhas , Drenagem , Humanos , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia/métodos
16.
Clin Hemorheol Microcirc ; 80(4): 487-495, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34897080

RESUMO

AIM: This study aims to evaluate optimized breast implant surface-structure analysis by comparing high-end ultrasound technology with a new high frequency technique. This comparative study used new breast implants with different surfaces in an in vitro setting. METHODS: Nine idle silicon or polyurethane (PU) breast implants were examined by two investigators in an experimental in vitro study using two high-end ultrasound devices with multi-frequency transducers (6-15 MHz, 9-16 MHz, 12.5-33 MHz).The ultrasound B-Mode was optimized using tissue harmonic imaging (THI), speckle reduction imaging (SRI, level 0-5), cross beam (high, medium, low) and photopic.Using a standardized ultrasound protocol, the implants were examined in the middle (point of highest projection) and lateral, by two independent examiners.Image evaluation was performed on anonymized digital images in the PACS. The aim was to achieve an artifact-free recording of the surface structure, the surface coating, the total image structures and, as far as possible, an artifact-free internal representation of the implants.For independent surface evaluation a score was used (0 = undetectability of surface structures, rich in artifacts, 5 = best possible, artifact free image quality). RESULTS: The quality of ultrasound imaging of breast implant surfaces after the optimization of B-Scan differed significantly comparing high-end ultrasound technology with modern high-frequency ultrasound technology (p < 0,05).The following setting has been found to be the best setting with the highest image quality:B-Mode, SRI value 3, Crossbeam high level with color coded imaging for B- mode. In the total examined frequency range of 6-33 MHz, the highest image quality was found in the average frequency range of 12.5-33 MHz at both measured points. For both devices, device 1 (high-end) and device 2 (high frequency) ultrasound, the image quality was in the12.5-33 MHz frequency range with an average image quality of 3.236. It was significantly higher, than in the lower frequency ranges and the same frequency range with THI. (p < 0,05). The image quality of the high-end sonography device was superior to the conventional high-frequency ultrasound device in all frequency ranges. CONCLUSION: High-end ultrasound imaging technology was superior in the quality of implant surface evaluation in comparison to high-frequency ultrasound sonography. The gained knowledge can serve as a basis for further multicenter clinical application and studies with the aim to develop an objective, precise tool to evaluate the implant and the surrounding tissue with ultrasound.


Assuntos
Implante Mamário , Implantes de Mama , Tecnologia , Transdutores , Ultrassonografia/métodos
17.
Clin Hemorheol Microcirc ; 79(1): 129-136, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34487025

RESUMO

In human cardiovascular research, sheep in particular are used as a large animal model in addition to pigs. In these animals, medical products, developed and tested for human medical purposes, are almost exclusively used in interventional studies. Therefore, the extent to which platelets from human and ovine blood differ in terms of adherence, aggregation and activation after a 4- or 8-minutes exposure to glass was investigated. Testing was performed with platelet-rich plasma (PRP) and a modified chandler loop-system, with 4- and 8-minute blood-material exposure times corresponding to 20 and 40 test cycles, respectively, through the entire silicone tube loop of the test system.In sheep and human PRP, contact with the silicone tubing resulted in a decrease in platelet count after 4 minutes and 20 test cycles, respectively. Four more minutes (20 additional test cycles) caused a further decrease of the platelet count only in sheep PRP. When the silicon tube was partly filled with glass beads, these effects were more pronounced and stronger in sheep then in human PRP.The mean platelet volume, which was used as parameter for platelet aggregation, did not change over time in human PRP without glass exposure. With glass exposure in human and sheep PRP the mean platelet volume increased within 40 test cycles, but this increase was stronger in sheep than in human PRP.Regarding activation behavior, the activation markers CD62P and CD63 were detectable only in < 30% (sheep) and < 45% (human) of platelets, whereas after 8 min of glass exposure, the proportion of CD62P+ and CD63+ cells was more increased than before only in sheep. These results indicate that ovine platelets adhere more strongly to glass and show stronger aggregation behavior after glass contact than human platelets, but that ovine and human platelets differ only slightly in activability by glass.


Assuntos
Plaquetas , Plasma Rico em Plaquetas , Animais , Humanos , Modelos Animais , Ativação Plaquetária , Agregação Plaquetária , Contagem de Plaquetas , Ovinos , Suínos
18.
Clin Hemorheol Microcirc ; 79(1): 193-203, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34487037

RESUMO

Arthrospira platensis (AP) and some of its derived products have well-established biological activities as antioxidants or as agents to reduce cardiovascular disease risk factors. Furthermore, AP products have gained increasing importance as potential anti-cancer agents. However, the ingredients of the available products vary greatly with the origin, the type of production and processing, which could have significant consequences for their biological effects. Therefore, the composition and biological influence of five distinct AP powders, which were acquired commercially or produced at a public biotechnology institute, were investigated in regard to their endothelialization capacity using a cell impedance- (CI) based measurement method. The study revealed that the AP composition and especially the influence on HUVEC proliferation differed significantly between the five AP powders up to 109%.Thus, it could be shown that the method used allows the reliable detection of quantitative differences in biological effects of different AP preparations.


Assuntos
Spirulina , Antioxidantes , Células Endoteliais , Pós
19.
Clin Hemorheol Microcirc ; 79(1): 149-155, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34487038

RESUMO

The pig is the most widely used large animal model in Europe, with cardiovascular research being one of the main areas of application. Adequate refinement of interventional studies in this field, meeting the requirements of Russel and Burchs' 3 R concept, can only be performed if blood-contacting medical devices are hemocompatible. Because most medical devices for cardiovascular interventional procedures are developed for humans they are tested mostly for compatibility with human blood. The aim of this study was therefore to determine whether there are differences in behavior of porcine and human platelets when they come into contact with glass, which was used as an exemplary thrombogenic material. For this purpose changes of platelet count, platelet volume and platelet expression of the activation markers CD61, CD62P and CD63 were measured using a modified chandler loop-system simulating the fluidic effects of the blood flow. Minipig and human platelets showed significant differences in number and volume, but not in activation after 4-8 min exposure to glass.


Assuntos
Plaquetas , Ativação Plaquetária , Animais , Citometria de Fluxo , Humanos , Contagem de Plaquetas , Suínos , Porco Miniatura
20.
Clin Hemorheol Microcirc ; 79(1): 27-38, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34334387

RESUMO

AIM: To improve preoperative diagnostics of solid non-cystic thyroid lesions by using new high-performance ultrasound techniques: optimized B-mode morphology, elastography, Color-Coded Doppler-Sonography (CCDS) and contrast enhanced ultrasound (CEUS)MATERIALS AND METHODS:In 33 cases solid, non-cystic thyroid lesions were rated as TIRADS 3 and up from conventional B-mode examinations. Additional high resolution Power Doppler including HR- and Glazing-Flow as optimized macrovascularization techniques, shear wave elastography and CEUS were performed on these patients by one experienced examiner. For CEUS a bolus of 1-2.4 ml Sulfurhexafluorid microbubbles (SonoVue®, Bracco, Milan, Italy) was injected into a cubital vein and then the distribution kinetics of the contrast agent were documented from the early arterial phase (10 to 15 seconds after injection) to the late venous phase (5 minutes after injection). Postoperative histopathology was the diagnostic gold standard as it provides the most reliable proof. RESULTS: 33 patients (13 males, 20 females; age 29 -77 years; mean 55 years; SD 13 years) were included in this study. 28 of them had benign regressive thyroid nodules, 3 had adenomas and 4 were diagnosed with carcinomas (3 were histologically identified as papillary thyroid carcinomas, one as a medullary thyroid carcinoma). The volume of the thyroid gland ranged from 6.6 to 401.3 cm2 (mean 72.6±92.0 cm2).The adenoma diameters ranged from 9 to 40 mm (mean 22±16 mm) and the carcinoma diameters ranged from 19 to 33 mm (mean 26±6 mm). The 3 adenomas had different echogenicities: One was completely echofree, one was hypoechoic and one isoechoic. The 4 carcinomas however were equally characterized as hypoechoic and echofree. Two of three adenomas and all of the carcinomas showed an incomplete or diffuse margin. Micro-calcifications were found in one adenoma and in every carcinoma. However, no micro-calcifications were observed in cases of benign regressive nodules.Performing shear-wave elastography the adenomas showed lower values than the carcinomas: The tissue velocity of the adenomas ranged from 2.86 m/s to 3.85 m/s (mean 3.32±0.5 m/s) and in carcinomas from 3.89 m/s to 5.66 m/s (mean 4.18±0.3 m/s).Marginal hypervascularization was detected in two adenomas after applying CCDS. One adenoma was hypovascularized. The four carcinomas showed an irregular extreme hypervascularization along their margins as well as an irregular central normo- or hypervascularization in CCDS. The additional HR-Flow helped reducing artefacts.In CEUS the dynamic capillary microvascularization of all carcinomas was very irregular with early enhancement and followed by partial or complete wash-out. In CEUS two adenomas had no wash-out and the other one showed a partial wash-out. CONCLUSION: Using modern multimodal imaging offers new possibilities for the differentiation between benign and malignant thyroid lesions. It is a very important diagnostic tool in addition to the B-Mode TIRADS classification and eases the decision between TIRADS 3, 4 and 5. However, additional multicenter studies are required for more detailed evaluations.


Assuntos
Meios de Contraste , Neoplasias da Glândula Tireoide , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Imagem Multimodal , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/cirurgia , Ultrassonografia
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