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1.
Rofo ; 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38885652

RESUMO

Over the last few years, there has been an increasing focus on integrating artificial intelligence (AI) into existing imaging systems. This also applies to ultrasound. There are already applications for thyroid and breast lesions that enable AI-assisted sonography directly on the device. However, this is not yet the case for lymph nodes.The aim was to test whether already established programs for AI-assisted sonography of breast lesions and thyroid nodules are also suitable for identifying and measuring superficial lymph nodes. For this purpose, the two programs were used as a supplement to routine ultrasound examinations of superficial lymph nodes. The accuracy of detection by AI was then evaluated using a previously defined score. If available, a comparison was made with cross-sectional imaging.The programs that were used are able to adequately detect lymph nodes in the majority of cases (78.6%). Problems were caused in particular by a high proportion of echo-rich fat, blurred differentiation from the surrounding tissues and the occurrence of lymph node conglomerates. The available cross-sectional images did not contradict the classification of the lesion as a lymph node in any case.In the majority of cases, the tested programs are already able to detect and measure superficial lymph nodes. Further improvement can be expected through specific training of the software. Further developments and studies are required to assess risk of malignancy. · The inclusion of AI in imaging is increasingly becoming a scientific focus.. · The detection of lymph nodes is already possible using device-integrated AI software.. · Malignancy assessment of the detected lymph nodes is not yet possible.. · Rink M, Künzel J, Stroszczynski C et al. Smart scanning: automatic detection of superficially located lymph nodes using ultrasound - initial results. Fortschr Röntgenstr 2024; DOI 10.1055/a-2331-0951.

2.
Life (Basel) ; 14(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38672731

RESUMO

In severe cases, SARS-CoV-2 infection leads to severe respiratory failure. Although angiotensin-converting enzyme 2 (ACE2) receptors are not expressed in red blood cells, SARS-CoV-2 can interact with red blood cells (RBCs) via several receptors or auxiliary membrane proteins. Recent data show that viral infection causes significant damage to the RBCs, altering their morphology, deformability, and aggregability. Loss of RBC deformability and/or increased aggregability favors the development of thrombotic processes in the microcirculation, as has been described to occur in COVID-19 patients. In addition, many patients also develop systemic endotheliitis associated with generalized coagulopathy. This manifests itself clinically as obstructive microthrombi in the area of the medium and smallest vessels, which can affect all internal organs. It is thought that such changes in the RBCs may contribute to the microangiopathy/microthrombosis associated with COVID-19 and may result in impaired capillary blood flow and tissue oxygenation.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38640145

RESUMO

OBJECTIVES: The purpose of this study was to investigate the effects of 6 weeks of resistance training (RT) combined with aerobic training (AT) and Tirzepatide supplementation on lipid profiles, insulin resistance, anthropometric characteristics and physical fitness in prediabetic obese soldiers. METHODS: 61 obese men were randomly divided into six groups: Placebo; Tirzepatide 5 mg (T5); Tirzepatide 2.5 mg (T2.5); Hypertrophy, Strength, Power-Circuit Training+Placebo (Ex+P); Hypertrophy, Strength, Power-Circuit Training+Tirzepatide 5 mg (Ex+T5); Hypertrophy, Strength, Power-Circuit Training+Tirzepatide 2.5 mg (Ex+T2.5). All training groups performed aerobic training (AT) after resistance training. Subjects trained for six weeks, three sessions per week. Before and after the intervention period, the participants were evaluated for anthropometric measures, body composition [body weight, body mass index (BMI), waist circumference (WC), waist to hip ratio (WHR) and fat mass (FM)], cardiorespiratory fitness (VO2max), and muscle strength (chest press 1RM and leg press 1RM). Blood biochemistry evaluations included triglyceride (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), fasting blood glucose (FBG), insulin level and insulin resistance (HOMA-IR). To evaluate the differences between the groups, ANCOVA statistical method was used along with Bonferroni's post hoc test, and the significance level was P <  0.05. RESULTS: Body weight, BMI, WC, FM, FBG, LDL-C, TC, TG and HOMA-IR were significantly decreased in Ex+P, Ex+T5 and Ex+T2.5 groups compared to Placebo, T5 and T2.5 groups. WHR significantly decreased in Ex+P, Ex+T5 and Ex+T2.5 groups compared to Placebo group. HDL-C, chest press and leg press significantly increased in Ex+P, Ex+T5 and Ex+T2.5 groups compared to Placebo, T5 and T2.5 groups. VO2max significantly increased and insulin significantly decreased in Ex+P group compared to Placebo, T5 and T2.5 groups. FM, FBG and TG were significantly decreased in both the T2.5 and T5 groups compared to Placebo group. HOMA-IR, LDL-C and TC significantly decreased in the T5 group compared to Placebo group. Also, leg press significantly increased in Ex+P group compared to all other groups. CONCLUSIONS: Performing six weeks of combined resistance and aerobic training in the form of RT+AT alone is more effective than the simultaneous use of Tirzepatide on cardiorespiratory fitness, strength, and modulating insulin levels. Taking Tirzepatide in doses of 5 mg and 2.5 mg in combination with exercise training did not have a significant advantage over exercise training alone. Finally, taking Tirzepatide in doses of 5 mg or 2.5 mg in combination with exercise training is not significantly superior to each other.

4.
Clin Hemorheol Microcirc ; 86(3): 263-273, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38489171

RESUMO

BACKGROUND: The continuous development of ultrasound techniques increasingly enables better description and visualization of unclear lesions. New ultrasound systems must be evaluated with regard to all these diagnostic possibilities. METHODS: A multifrequency C1-7 convex probe (SC7-1M) with the new high-end system Resona A20 Series was used. Modern technologies, including HiFR CEUS, SR CEUS and multimodal tissue imaging with shear wave elastography (SWE), fat evaluation and viscosity measurements (M-Ref) were applied. RESULTS: Of n = 70 (mean value 48,3 years±20,3 years, range 18-84 years) cases examined, a definitive diagnosis could be made in n = 67 cases, confirmed by reference imaging and/or follow-up. Of these, n = 22 cases were malignant changes (HCC (hepatocellular carcinoma) n = 9, CCC (cholangiocellular carcinoma) n = 3, metastases of colorectal carcinomas or recurrences of HCC n = 10). In all 12 cases of HCC or CCC, the elastography measurements using the shear wave technique (with values >2 m/s to 3.7 m/s) showed mean values of 2.3±0.31 m/s and a degree of fibrosis of F2 to F4. In n = 14 cases, changes in the fat measurement (range 0.51 to 0.72 dB/cm/MHz, mean values 0.58±0.12 dB/cm/MHz) in the sense of proportional fatty changes in the liver were detected. In the 4 cases of localized fat distribution disorders, the values were >0.7 dB/cm/MHz in the sense of significant fatty deposits in the remaining liver tissue. Relevant changes in the viscosity measurements with values >1.8 kPa were found in n = 31 cases, in n = 5 cases of cystic lesions with partially sclerosing cholangitis, in n = 13 cases of malignant lesions and in n = 9 cases post-interventionally, but also in n = 4 cases of benign foci with additional systemic inflammation. CONCLUSIONS: The results are promising and show a new quality of ultrasound-based liver diagnostics. However, there is a need for further investigations with regard to the individual aspects, preferably on a multi-center basis.


Assuntos
Carcinoma Hepatocelular , Técnicas de Imagem por Elasticidade , Neoplasias Hepáticas , Humanos , Técnicas de Imagem por Elasticidade/métodos , Meios de Contraste , Carcinoma Hepatocelular/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Viscosidade , Fígado/diagnóstico por imagem , Fígado/patologia , Ultrassonografia/métodos
5.
Artigo em Inglês | MEDLINE | ID: mdl-38306027

RESUMO

 Ferroptosis is a form of programmed cell death that plays a significant role in causing several diseases such as heart attack and heart failure, through alterations in fat, amino acid, and iron metabolism. Comprehending the regulatory mechanisms of ferroptosis signaling is critical because it has a considerable effect on the elderly's mortality. Conversely, age-related changes in substrate metabolism and metabolite levels are recognized to give rise to obesity. Furthermore, research has proposed that aging and obesity-related changes in substrate metabolism may aggravate ferroptosis. The suppression of ferroptosis holds potential as a successful therapeutic approach for managing different diseases, including sarcopenia, cardiovascular diseases, and central nervous system diseases. However, the pathologic and biological mechanisms behind the function of ferroptosis are not fully comprehended yet. Physical activity could affect lipid, amino acid, and iron metabolism to modulate ferroptosis. The aim of this study is to showcase the current understanding of the molecular mechanisms leading to ferroptosis and discuss the role of aging and physical activity in this phenomenon.

6.
Clin Hemorheol Microcirc ; 86(1-2): 159-168, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37638428

RESUMO

BACKGROUND: Liver biotransformation is the major route for drug metabolism in humans, often catalysed by cytochrome P450 (CYP) enzymes. This first-pass effect can lead to hepatotoxicity and influences the bioavailability of drugs. OBJECTIVE: We aimed to establish in vitro culture systems simulating the liver first-pass to study effects of the proteasome inhibitor MG-132 simultaneously on hepatocytes and cancer cells. METHODS: The first-pass effect was simulated by conditioned medium transfer (CMT) from pre-treated HepG2 CYP3A4-overexpressing cells to either pancreatic cancer cell line PANC-1 or primary colon cancer cells, and by indirect co-culture (CC) of liver and cancer cells in a shared medium compartment. Experimental proteasome inhibitor MG-132 was used as test substance as it is detoxified by CYP3A4. RESULTS: Cancer cells showed higher viabilities in the first-pass simulation by CMT and CC formats when compared to monocultures indicating effective detoxification of MG-132 by HepG2 CYP3A4-overexpressing cells. HepG2-CYP3A4 cells showed reduced viabilites after treatment with MG-132. CONCLUSIONS: We successfully established two different culture systems to simulate the liver first-pass effect in vitro. Such systems easily allow to study drug effects simultaneously on liver and on target cancer cells. They are of great value in pre-clinical cancer research, pharmaceutical research and drug development.


Assuntos
Citocromo P-450 CYP3A , Leupeptinas , Neoplasias , Humanos , Células Hep G2 , Inibidores de Proteassoma/farmacologia , Fígado , Sistema Enzimático do Citocromo P-450/metabolismo , Biotransformação
8.
Clin Hemorheol Microcirc ; 86(1-2): 89-97, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37574725

RESUMO

OBJECTIVE: To test and initially describe a new handheld wireless ultrasound technique (TE Air) for clinical use. METHODS: In this pilot study, the new ultrasound device TE Air from Mindray was used to examine the hepatic and renal vessels of healthy volunteers for first impressions. The probe has a sector transducer with a frequency range of 1.8-4.5 MHz. The B-mode and color-coded doppler sonography (CCDS) scanning methods were used. A high-end device from the same company (Resona 9, Mindray) was used as a reference. The results were evaluated using an image rating scale ranging from 0 to 5, with 0 indicating not assessable and 5 indicating without limitations. RESULTS: Altogether, 61 participants (n = 34 female [55.7%], n = 27 male [44.3%]), age range 18-83 years, mean age 37.9±16.5 years) could be adequately studied using TE AIR and the high-end device. With one exception, the image quality score for TE Air never fell below 3 and had a mean/median scored of 4.97/5.00 for the B-mode, 4.92/5.00 for the color flow (CF) mode, and 4.89/5.00 for the pulse wave (PW) mode of the hepatic vein, 4.90/5.00 for the portal vein, 4.11/4.00 for the hepatic artery, and 4.57/5.00 for the renal segmental artery. A significant difference in the assessment of flow measurement of the hepatic artery and renal segmental arteries was found between TE AIR and the high-end device. CONCLUSIONS: TE Air represents a new dimension in point-of-care ultrasound via wireless handheld devices. Especially, its flow measurement ability offers a relevant advantage over other available handheld models. TE Air provides a formally sufficient image quality in terms of diagnostic significance.


Assuntos
Veia Porta , Ultrassonografia Doppler em Cores , Humanos , Masculino , Feminino , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Projetos Piloto , Ultrassonografia , Veia Porta/diagnóstico por imagem , Fígado
9.
J Gastrointestin Liver Dis ; 32(4): 479-487, 2023 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-38147619

RESUMO

AIMS: To assess the value of using integrated parametric ultrasound software for contrast-enhanced ultrasonography (CEUS) of liver tumors. METHODS: 107 patients with liver tumors were studied. CEUS were performed to detect focal lesions. Parametric images were based on continuous CINE LOOPs, from the early-arterial phase (15 s) to the portal-venous phase (1 min) generated by perfusion software. The evaluations of the parametric images and their dignity for liver lesions were performed independently by an experienced and a less-experienced investigator. Computed tomography, magnetic resonance imaging scans or histological analysis were used as references. RESULTS: High parametric image quality were obtained in all patients. Among the patients, 44% lesions were benign, 56% were malignant. The experienced investigator correctly classified 46 of 47 (98%) as benign, and 60 of 60 (100%) as malignant tumors based on the parametric images. The less-experienced investigator correctly classified 39 of 47 (83%) as benign, and 49 of 60 (82%) malignant tumors, acheaving a high statistical accuracy of 98% with this type of diagnostic. CONCLUSION: Parametric imaging for grading the malignant degree of tumor may be a good complement to existing ultrasound techniques and was particularly helpful for improving the assessments of the less-experienced examiner.


Assuntos
Interpretação de Imagem Assistida por Computador , Neoplasias Hepáticas , Ultrassonografia , Humanos , Meios de Contraste , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Perfusão/métodos , Sensibilidade e Especificidade , Ultrassonografia/métodos , Software
11.
Cells ; 12(17)2023 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-37681872

RESUMO

In the liver, phase-1 biotransformation of drugs and other xenobiotics is largely facilitated by enzyme complexes consisting of cytochrome P450 oxidoreductase (CPR) and cytochrome P450 monooxygenases (CYPs). Generated from human liver-derived cell lines, recombinant in vitro cell systems with overexpression of defined phase-1 enzymes are widely used for pharmacological and toxicological drug assessment and laboratory-scale production of drug-specific reference metabolites. Most, if not all, of these cell lines, however, display some background activity of several CYPs, making it difficult to attribute effects to defined CYPs. The aim of this study was to generate cell lines with stable overexpression of human phase-1 enzymes based on Chinese hamster ovary (CHO) suspension cells. Cells were sequentially modified with cDNAs for human CPR in combination with CYP1A2, CYP2B6, or CYP3A4, using lentiviral gene transfer. In parallel, CYP-overexpressing cell lines without recombinant CPR were generated. Successful recombinant expression was demonstrated by mRNA and protein analyses. Using prototypical CYP-substrates, generated cell lines proved to display specific enzyme activities of each overexpressed CYP while we did not find any endogenous activity of those CYPs in parental CHO cells. Interestingly, cell lines revealed some evidence that the dependence of CYP activity on CPR could vary between CYPs. This needs to be confirmed in further studies. Recombinant expression of CPR was also shown to enhance CYP3A4-independent metabolisation of testosterone to androstenedione in CHO cells. We propose the novel serum-free CHO suspension cell lines with enhanced CPR and/or defined CYP activity as a promising "humanised" in vitro model to study the specific effects of those human CYPs. This could be relevant for toxicology and/or pharmacology studies in the pharmaceutical industry or medicine.


Assuntos
Citocromo P-450 CYP3A , Sistema Enzimático do Citocromo P-450 , Animais , Cricetinae , Humanos , Células CHO , Cricetulus , Citocromo P-450 CYP3A/genética , Biotransformação
12.
Cells ; 12(15)2023 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-37566045

RESUMO

Cancer patients are at a very high risk of serious thrombotic events, often fatal. The causes discussed include the detachment of thrombogenic particles from tumor cells or the adverse effects of chemotherapeutic agents. Cytostatic agents can either act directly on their targets or, in the case of a prodrug approach, require metabolization for their action. Cyclophosphamide (CPA) is a widely used cytostatic drug that requires prodrug activation by cytochrome P450 enzymes (CYP) in the liver. We hypothesize that CPA could induce thrombosis in one of the following ways: (1) damage to endothelial cells (EC) after intra-endothelial metabolization; or (2) direct damage to EC without prior metabolization. In order to investigate this hypothesis, endothelial cells (HUVEC) were treated with CPA in clinically relevant concentrations for up to 8 days. HUVECs were chosen as a model representing the first place of action after intravenous CPA administration. No expression of CYP2B6, CYP3A4, CYP2C9 and CYP2C19 was found in HUVEC, but a weak expression of CYP2C18 was observed. CPA treatment of HUVEC induced DNA damage and a reduced formation of an EC monolayer and caused an increased release of prostacyclin (PGI2) and thromboxane (TXA) associated with a shift of the PGI2/TXA balance to a prothrombotic state. In an in vivo scenario, such processes would promote the risk of thrombus formation.


Assuntos
Neoplasias , Pró-Fármacos , Trombose , Humanos , Pró-Fármacos/farmacologia , Antineoplásicos Alquilantes/farmacologia , Antineoplásicos Alquilantes/uso terapêutico , Células Endoteliais/metabolismo , Ciclofosfamida/uso terapêutico , Sistema Enzimático do Citocromo P-450/metabolismo , Neoplasias/tratamento farmacológico , Trombose/tratamento farmacológico
13.
Clin Hemorheol Microcirc ; 83(3): 305-314, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36683497

RESUMO

BACKGROUND: Physical training in patients with heart failure can affect hemodynamic, cardiac and angiogenesis parameters. OBJECTIVE: The aim of the present study was to investigate the effects of traditional moderate-intensity rehabilitation training and interval training on some angiogenesis factors in coronary artery bypass graft (CABG) patients. METHODS: Thirty CABG patients (mean age±SD, 55±3 years) were randomly assigned to one of three groups: high-intensity interval training (HIIT) or moderate-intensity continuous training (MICT) or the control group. After the initial assessments, eligible patients in the experimental groups (HIIT and MICT) performed exercise training for 8 weeks, while the control group did not. Angiogenesis and angiostatic indices, including pro-adrenomedullin (pro-ADM), basic fibroblast growth factor (bFGF), and endostatin, were then measured. RESULTS: The results showed no significant difference between pro-ADM in the HIIT and MICT groups (P = 0.99), but a significant difference was found between MICT and the control group and between HIIT and the control group (P = 0.001). There is also no significant difference between the bFGF levels in the HIIT and MICT training groups (P = 1.00), but the changes in this factor between the training groups and the control group were significant (P = 0.001). There was a significant difference between the levels of endostatin in all three groups. CONCLUSIONS: Two methods of cardiac rehabilitation (HIIT and MICT) may be useful for the recovery of patients with coronary artery bypass grafting. This improvement manifested itself in changes in angiogenesis and angiostatic indices in this study. However, more extensive studies are needed to investigate the effects of these two types of rehabilitation programs on other indicators of angiogenesis and angiostatic.


Assuntos
Reabilitação Cardíaca , Ponte de Artéria Coronária , Exercício Físico , Treinamento Intervalado de Alta Intensidade , Humanos , Pessoa de Meia-Idade , Reabilitação Cardíaca/métodos , Endostatinas , Treinamento Intervalado de Alta Intensidade/métodos
14.
Clin Hemorheol Microcirc ; 83(1): 31-46, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35466932

RESUMO

AIM: To examine to what extent the high frame rate contrast-enhanced ultrasound (HiFR) diagnostic enables the conclusive diagnosis of liver changes with suspected malignancy. MATERIAL/METHODS: Ultrasound examinations were performed by an experienced examiner using a multifrequency probe (SC6-1) on a high-end ultrasound system (Resona 7, Mindray) to clarify liver changes that were unclear on the B-scan. A bolus of 1-2.4 ml of the Sulphur hexafluoride ultrasound microbubbles contrast agent SonoVue™ (Bracco SpA, Italy) was administered with DICOM storage of CEUS examinations from the early arterial phase (5-15 s) to the late phase (5-6 min). Based on the image files stored in the PACS, an independent reading was performed regarding image quality and finding-related diagnostic significance (0 not informative/non-diagnostic to 5 excellent image quality/confident diagnosis possible). References were clinical follow-up, if possible, comparison to promptly performed computed tomography or magnetic resonance imaging, in some cases also to histopathology. RESULTS: We examined 100 patients (42 women, 58 men, from 18 years to 90 years, mean 63±13 years) with different entities of focal and diffuse liver parenchymal changes, which could be detected in all cases with sufficient image quality with CEUS and with high image quality with HiFR-CEUS. Proportionally septate cysts were found in n = 19 cases, scars after hemihepatectomy with local reduced fat in n = 5 cases, scars after microwave ablation in n = 19 cases, hemangiomas in n = 9 cases, focal nodular hyperplasia in n = 8 cases, colorectal metastases in n = 15 cases, hepatocellular carcinoma (HCC) in n = 11 cases, Osler disease in n = 8 cases. The size of lesions ranged from 5 mm to 200 mm with a mean value of 33.1±27.8 mm. Conclusive diagnoses could be made by the experienced investigator in 97/100 cases with CEUS, confirmed by reference imaging, in parts by histopathology or follow-up. The image quality for HiFR CEUS was rated with a score of 3 to 5; 62 cases were assessed with an average of good (4 points), 27 cases with very good (5 points), and in 11 cases (3 points) still satisfactory despite aggravated acoustic conditions. The specificity of HIFR-CEUS was 97%, the sensitivity 97%, the positive predictive value 94%, the negative predictive value 99% and the accuracy 97%. CONCLUSION: HIFR-CEUS has demonstrated has demonstrated an improved image quality resulting in a high diagnostic accuracy. In the hands of an experienced investigator, HiFR-CEUS allows the assessment of focal and diffuse unclear liver parenchymal changes on B-scan and dynamic assessment of microcirculation in solid and vascular changes.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Masculino , Humanos , Feminino , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Cicatriz/patologia , Meios de Contraste , Ultrassonografia/métodos , Imageamento por Ressonância Magnética
15.
Life (Basel) ; 12(10)2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36294932

RESUMO

The cyanobacterium Arthrospira platensis (Spirulina platensis) is a natural source of considerable amounts of ingredients that are relevant for nutra- and pharmaceutical uses. Different hydrophilic and hydrophobic substances can be obtained by extraction from the biomass. The respective extraction techniques determine the composition of substances in the extract and thus its biological activity. In this short review, we provide an overview of the hydrophilic compounds (phenols, phycobiliproteins, polysaccharides, and vitamins) and lipophilic ingredients (chlorophylls, vitamins, fatty acids, and glycolipids) of Arthrospira platensis. The principal influences of these substances on blood and tissue cells are briefly summarized.

16.
Cells ; 11(15)2022 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-35954291

RESUMO

The characterization of novel radiotracers toward their metabolic stability is an essential part of their development. While in vitro methods such as liver microsome assays or ex vivo blood or tissue samples provide information on overall stability, little or no information is obtained on cytochrome P450 (CYP) enzyme and isoform-specific contribution to the metabolic fate of individual radiotracers. Herein, we investigated recently established CYP-overexpressing hepatoblastoma cell lines (HepG2) for their suitability to study the metabolic stability of radiotracers in general and to gain insight into CYP isoform specificity. Wildtype HepG2 and CYP1A2-, CYP2C19-, and CYP3A4-overexpressing HepG2 cells were incubated with radiotracers, and metabolic turnover was analyzed. The optimized protocol, covering cell seeding in 96-well plates and analysis of supernatant by radio thin-layer-chromatography for higher throughput, was transferred to the evaluation of three 18F-labeled celecoxib-derived cyclooxygenase-2 inhibitors (coxibs). These investigations revealed time-dependent degradation of the intact radiotracers, as well as CYP isoform- and substrate-specific differences in their metabolic profiles. HepG2 CYP2C19 proved to be the cell line showing the highest metabolic turnover for each radiotracer studied here. Comparison with human and murine liver microsome assays showed good agreement with the human metabolite profile obtained by the HepG2 cell lines. Therefore, CYP-overexpressing HepG2 cells provide a good complement for assessing the metabolic stability of radiotracers and allow the analysis of the CYP isoform-specific contribution to the overall radiotracer metabolism.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Linhagem Celular , Citocromo P-450 CYP2C19 , Sistema Enzimático do Citocromo P-450/metabolismo , Humanos , Camundongos , Isoformas de Proteínas
17.
Clin Hemorheol Microcirc ; 82(3): 231-238, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35723091

RESUMO

BACKGROUND: Ultrasound follow-up of transjugular intrahepatic portosystemic shunt (TIPS) is challenging due to the bent course of the stent-graft. OBJECTIVE: Aim of this retrospective study was to assess to which extent the combination of HR flow with Glazing Flow improves hemodynamic assessment in the ultrasound follow-up of TIPS. METHODS: Comparative studies with CCDS and High Resolution (HR)-Flow with Glazing Flow were evaluated regarding image quality and artifacts on a 5-point scale (0 = cannot be assessed up to 5 = maximum image quality without artifacts). In all cases, an experienced examiner performed the examinations with a 1-6 MHz probe (Resona 7, Mindray). RESULTS: 61 ultrasound examinations in 48 patients were performed; the mean patient age was 54±14.2 years. The use of HR-Flow with Glazing Flow resulted in an improved flow display in 55/61 cases (90.2%). Both methods correlated well (r = 0.71), but HR flow with Glazing flow values were in general higher than CCDS values. The reading resulted in an average value of 2.52±0.54 for CCDS and 3.52±0.57 for HR flow with Glazing flow (p = 0.013). CONCLUSION: The combination of HR-Flow and Glazing Flow results in improved flow representation and reduction of artifacts in the ultrasound follow-up of TIPS.


Assuntos
Hemodinâmica , Veia Porta , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Estudos Retrospectivos , Velocidade do Fluxo Sanguíneo , Stents , Resultado do Tratamento
18.
Life (Basel) ; 12(6)2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35743926

RESUMO

Light-emitting diodes (LED) can be utilized as tailorable artificial light sources for the cultivation of cyanobacteria such as Arthrospira platensis (AP). To study the influence of different LED light colors on phototrophic growth and biomass composition, AP was cultured in closed bioreactors and exposed to red, green, blue, or white LED lights. The illumination with red LED light resulted in the highest cell growth and highest cell densities compared to all other light sources (order of cell densities: red > white > green > blue LED light). In contrast, the highest phycocyanin concentrations were found when AP was cultured under blue LED light (e.g., order of concentrations: blue > white > red > green LED light). LED-blue light stimulated the accumulation of nitrogen compounds in the form of phycobiliproteins at the expense of cell growth. The results of the study revealed that exposure to different LED light colors can improve the quality and quantity of the biomass gained in AP cultures.

19.
Clin Hemorheol Microcirc ; 80(2): 107-116, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34420942

RESUMO

BACKGROUND: Type two diabetes mellitus (T2DM) patients are prone to develop atherothrombotic events due to platelet hyper-reactivity stemming from platelet miRNA-223 down-regulation and over-expression of its corresponding target, P2RY12. OBJECTIVE: The study sought to determine the effects of long-term aerobic training on the expression levels of miRNA-223 and P2RY12 mRNA, and platelet function in T2DM patients. METHODS: Twenty-four patients with T2DM (age, 60.0±2.8 yrs.) were selected and randomly divided into two groups: aerobic exercise training (AET, n = 12) and control (CON, n = 12). The AET protocol was performed with moderate intensity for 12 weeks, while patients in the CON group followed their usual routine. Weight, body mass index (BMI), peak oxygen consumption (VO2peak), lipid profile, fasting blood glucose (FBG), glycated hemoglobin (HbA1c), insulin resistance index (HOMA-IR), platelet miRNA-223 and P2RY12 expression were measured before and after the period. RESULTS: There was a significant improvement in body weight, BMI, VO2peak, FBG, HbA1c, and HOMA-IR, after 12 weeks of AET (P < 0.01). Platelet aggregation decreased significantly after 12 weeks in the AET group compared with the CON (P < 0.001) group. Platelets' miRNA-223 and P2RY12 were significantly up- and down-regulated after AET in comparison with the CON group (P < 0.05), respectively. Moreover, the relative expression of miRNA-223 and P2RY12 significantly correlated with FBG changes following the intervention. CONCLUSIONS: It can be concluded that long-term moderate-intensity aerobic training might be effective for reducing the occurrence of atherothrombotic events leading to premature death in T2DM patients through the modulation of miRNA-223, P2RY12 receptor expression, and platelet function.


Assuntos
Diabetes Mellitus Tipo 2 , MicroRNAs , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/terapia , Exercício Físico/fisiologia , Hemoglobinas Glicadas/metabolismo , Humanos , MicroRNAs/genética , Pessoa de Meia-Idade , Receptores Purinérgicos P2Y12
20.
Clin Hemorheol Microcirc ; 79(1): 231-243, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34487034

RESUMO

Cell-based in vitro liver models are an important tool in the development and evaluation of new drugs in pharmacological and toxicological drug assessment. Hepatic microsomal enzyme complexes, consisting of cytochrome P450 oxidoreductase (CPR) and cytochrome P450 monooxygenases (CYPs), play a decisive role in catalysing phase-1 biotransformation of pharmaceuticals and xenobiotics. For a comprehensive understanding of the phase-1 biotransformation of drugs, the availability of well-characterized substances for the targeted modulation of in vitro liver models is essential. In this study, we investigated diphenyleneiodonium (DPI) for its ability to inhibit phase-1 enzyme activity and further its toxicological profile in an in vitro HepG2 cell model with and without recombinant expression of the most important drug metabolization enzyme CYP3A4.Aim of the study was to identify effective DPI concentrations for CPR/CYP activity modulation and potentially associated dose and time dependent hepatotoxic effects. The cells were treated with DPI doses up to 5,000nM (versus vehicle control) for a maximum of 48 h and subsequently examined for CYP3A4 activity as well as various toxicological relevant parameters such as cell morphology, integrity and viability, intracellular ATP level, and proliferation. Concluding, the experiments revealed a time- and concentration-dependent DPI mediated partial and complete inhibition of CYP3A4 activity in CYP3A4 overexpressing HepG2-cells (HepG2-CYP3A4). Other cell functions, including ATP synthesis and consequently the proliferation were negatively affected in both in vitro cell models. Since neither cell integrity nor cell viability were reduced, the effect of DPI in HepG2 can be assessed as cytostatic rather than cytotoxic.


Assuntos
Citostáticos , Hepatoblastoma , Neoplasias Hepáticas , Biotransformação , Linhagem Celular , Células Clonais , Citocromo P-450 CYP3A/genética , Células Hep G2 , Hepatoblastoma/tratamento farmacológico , Humanos , Oniocompostos
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