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1.
NPJ Parkinsons Dis ; 10(1): 124, 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38918417

ABSTRACT

Striosomes and matrix are two compartments that comprise the striatum, each having its own distinct immunohistochemical properties, function, and connectivity. It is currently not clear whether prodromal or early manifest Parkinson's disease (PD) is associated with any striatal matrix or striosomal abnormality. Recently, a method of striatal parcellation using probabilistic tractography has been described and validated, using the distinct connectivity of these two compartments to identify voxels with striosome- and matrix-like connectivity. The goal of this study was to use this approach in tandem with DAT-SPECT, a method used to quantify the level of nigrostriatal denervation, to analyze the striatum in populations of de novo diagnosed, treatment-naïve patients with PD, isolated REM behavioral disorder (iRBD) patients, and healthy controls. We discovered a shift in striatal connectivity, which showed correlation with nigrostriatal denervation. Patients with PD exhibited a significantly higher matrix-like volume and associated connectivity than healthy controls and higher matrix-associated connectivity than iRBD patients. In contrast, the side with less pronounced nigrostriatal denervation in PD and iRBD patients showed a decrease in striosome-like volume and associated connectivity indices. These findings could point to a compensatory neuroplastic mechanism in the context of nigrostriatal denervation and open a new avenue in the investigation of the pathophysiology of Parkinson's disease.

2.
Physiol Res ; 71(4): 517-526, 2022 Aug 31.
Article in English | MEDLINE | ID: mdl-35770473

ABSTRACT

Metabolic flux investigations of cells and tissue samples are a rapidly advancing tool in diverse research areas. Reliable methods of data normalization are crucial for an adequate interpretation of results and to avoid a misinterpretation of experiments and incorrect conclusions. The most common methods for metabolic flux data normalization are to cell number, DNA and protein. Data normalization may be affected by a variety of factors, such as density, healthy state, adherence efficiency, or proportional seeding of cells. The mussel-derived adhesive Cell-Tak is often used to immobilize poorly adherent cells. Here we demonstrate that this coating strongly affects the fluorescent detection of DNA leading to an incorrect and highly variable normalization of metabolic flux data. Protein assays are much less affected and cell counting can virtually completely remove the effect of the coating. Cell-Tak coating also affects cell shape in a cell line-specific manner and may change cellular metabolism. Based on these observations we recommend cell counting as a gold standard normalization method for Seahorse metabolic flux measurements with protein content as a reasonable alternative.


Subject(s)
DNA , Membrane Proteins
3.
Rev. esp. med. nucl. imagen mol. (Ed. impr.) ; 39(5): 279-283, sept.-oct. 2020. ilus, tab
Article in Spanish | IBECS | ID: ibc-198289

ABSTRACT

ANTECEDENTES: El hiperinsulinismo congénito (HIC) es una enfermedad neuroendocrina con anomalías focales o difusas en el páncreas. Mientras que las formas difusas resistentes a los medicamentos requieren una pancreatectomía casi total o una farmacoterapia prolongada, el HIC focal podría ser tratado por resección quirúrgica dirigida. Por tanto, evaluamos la utilidad del 18F-DOPA PET/TC para identificar la forma pancreática focal. Objetivos y metodología: Diecinueve niños (11 niños y 8 niñas de 2 a 54meses de edad) con signos clínicos de HIC neonatal y exámenes genéticos positivos fueron registrados en el estudio. Después de la administración intravenosa del 18F-DOPA, una primera PET y posteriormente otra PET/TC cubriendo longitudinalmente la región toracoabdominal fueron llevadas a cabo. Ambas adquisiciones fueron realizadas en modo dinámico para permitir la exclusión de imágenes con artefactos de movimiento. Los valores de absorción estandarizados fueron ajustados al peso corporal (SUVbw). El hallazgo fue considerado como focal cuando la proporción de SUVbwmax entre la región sospechosa y el resto del páncreas fue mayor que 1,2. RESULTADOS: Las formas focales fueron registradas en 10/19 niños y 4 de ellos se sometieron a una resección quirúrgica con recuperación completa. La captación focal fue significativamente mayor que la captación en el tejido pancreático normal (p = 0,0059). Las formas focales y difusas del HIC no difieren significativamente en la captación del tejido pancreático normal. No encontramos ninguna ventaja en la medición de la relación SUVbwmean en comparación con la relación SUVbwmax (p = 0,50). CONCLUSIONES: 18F-DOPA PET/TC es una herramienta útil para la localización de HIC focal y la planificación de un tratamiento quirúrgico


BACKGROUND: Congenital hyperinsulinism (CHI) is a neuroendocrine disease with focal or diffuse abnormalities in pancreas. While drug-resistant diffuse forms require near-total pancreatectomy or prolonged pharmacotherapy, focal CHI may be treated by targeted surgical resection. We evaluated the usefulness of 18F-DOPA PET/CT to identify the focal pancreatic form. Subjects and methods: Nineteen children (11 boys, 8 girls, aged 2-54 months) with clinical signs of neonatal CHI and positive genetic examinations were enrolled in the study. After i.v. administration of 18F-DOPA, early PET and late PET/CT acquisition covering one-bed length over thoraco-abdominal region were performed. Both acquisitions were done in dynamic mode to allow exclusion of frames with motion artefacts. Standardized uptake values were adjusted to bodyweight (SUVbw). The finding was considered as focal when the ratio of SUVbwmax between the suspicious region and the rest of pancreas was greater than 1.2. RESULTS: Focal forms were recorded in 10/19 children and 4 of them underwent surgical resection with complete recovery. Focal uptake was significantly higher than the uptake in the normal pancreatic tissue (p = 0.0059). Focal and diffuse forms of CHI did not differ significantly in normal pancreatic tissue uptake. We found no advantage in the measurement of SUVbwmean ratio compared to SUVbwmax ratio (p = 0.50). CONCLUSION: 18F-DOPA PET/CT is a useful tool for the localization of focal CHI and planning of surgical treatment


Subject(s)
Humans , Male , Female , Infant , Child, Preschool , Congenital Hyperinsulinism/diagnostic imaging , Positron Emission Tomography Computed Tomography/methods , Pancreas/diagnostic imaging , Radiopharmaceuticals/administration & dosage , Insulinoma/diagnostic imaging , Radioactive Tracers , Octreotide/therapeutic use , Diazoxide/therapeutic use
4.
Sleep Med ; 70: 116-123, 2020 06.
Article in English | MEDLINE | ID: mdl-32403038

ABSTRACT

OBJECTIVES: Hyperechogenicity of the substantia nigra (SN) and abnormal dopamine transporter-single-photon emission computed tomography (DAT-SPECT) are biomarkers commonly used in the assessment of prodromal synucleinopathy. Our goals were as follows: (1) to compare echogenicity of SN in idiopathic rapid eye movement (REM) behavior disorder (iRBD), Parkinson's disease (PD) without RBD (PD-noRBD), PD with RBD (PD + RBD), and control subjects; and (2) to examine association between SN degeneration assessed by DAT-SPECT and SN echogenicity. PATIENTS/METHODS: A total of 61 subjects with confirmed iRBD were examined using Movement Disorders Society-unified PD rating scale (MDS-UPDRS), TCS (transcranial sonography) and DAT-SPECT. The results were compared with 44 patients with PD (25% PD + RBD) and with 120 age-matched healthy subjects. RESULTS AND CONCLUSION: The abnormal SN area was found in 75.5% PD, 23% iRBD and 7.3% controls. Median SN echogenicity area in PD (0.27 ± 0.22 cm2) was higher compared to iRBD (0.07 ± 0.07 cm2; p < 0.0001) and controls (0.05 ± 0.03 cm2; p < 0.0001). SN echogenicity in PD + RBD was not significantly different from PD-noRBD (0.30 vs. 0.22, p = 0.15). Abnormal DAT-SPECT was found in 16 iRBD (25.4%) and 44 PD subjects (100%). No correlation between the larger SN area and corresponding putaminal binding index was found in iRBD (r = -0.13, p = 0.29), nor in PD (r = -0.19, p = 0.22). The results of our study showed that: (1) SN echogenicity area in iRBD was higher compared to controls, but the hyperechogenicity was present only in a minority of iRBD patients; (2) SN echogenicity and DAT-SPECT binding index did not correlate in either group; and (3) SN echogenicity does not differ between PD with/without RBD.


Subject(s)
REM Sleep Behavior Disorder , Substantia Nigra , Synucleinopathies , Humans , Iodine Radioisotopes , Nortropanes , REM Sleep Behavior Disorder/diagnostic imaging , REM Sleep Behavior Disorder/physiopathology , Substantia Nigra/diagnostic imaging , Substantia Nigra/physiopathology , Synucleinopathies/diagnostic imaging , Synucleinopathies/physiopathology , Tomography, Emission-Computed, Single-Photon , Ultrasonography, Doppler, Transcranial
5.
Article in English, Spanish | MEDLINE | ID: mdl-32448747

ABSTRACT

BACKGROUND: Congenital hyperinsulinism (CHI) is a neuroendocrine disease with focal or diffuse abnormalities in pancreas. While drug-resistant diffuse forms require near-total pancreatectomy or prolonged pharmacotherapy, focal CHI may be treated by targeted surgical resection. We evaluated the usefulness of 18F-DOPA PET/CT to identify the focal pancreatic form. SUBJECTS AND METHODS: Nineteen children (11 boys, 8 girls, aged 2-54 months) with clinical signs of neonatal CHI and positive genetic examinations were enrolled in the study. After i.v. administration of 18F-DOPA, early PET and late PET/CT acquisition covering one-bed length over thoraco-abdominal region were performed. Both acquisitions were done in dynamic mode to allow exclusion of frames with motion artefacts. Standardized uptake values were adjusted to bodyweight (SUVbw). The finding was considered as focal when the ratio of SUVbwmax between the suspicious region and the rest of pancreas was greater than 1.2. RESULTS: Focal forms were recorded in 10/19 children and 4 of them underwent surgical resection with complete recovery. Focal uptake was significantly higher than the uptake in the normal pancreatic tissue (p=0.0059). Focal and diffuse forms of CHI did not differ significantly in normal pancreatic tissue uptake. We found no advantage in the measurement of SUVbwmean ratio compared to SUVbwmax ratio (p=0.50). CONCLUSION: 18F-DOPA PET/CT is a useful tool for the localization of focal CHI and planning of surgical treatment.


Subject(s)
Congenital Hyperinsulinism/diagnostic imaging , Dihydroxyphenylalanine/analogs & derivatives , Fluorine Radioisotopes , Pancreatectomy/methods , Positron Emission Tomography Computed Tomography/methods , Radiopharmaceuticals , Surgery, Computer-Assisted , Child, Preschool , Combined Modality Therapy , Congenital Hyperinsulinism/drug therapy , Congenital Hyperinsulinism/physiopathology , Congenital Hyperinsulinism/surgery , Diazoxide/therapeutic use , Dihydroxyphenylalanine/pharmacokinetics , Female , Fluorine Radioisotopes/pharmacokinetics , Humans , Infant , Insulinoma/complications , Insulinoma/surgery , Male , Neuroendocrine Cells/metabolism , Octreotide/therapeutic use , Pancreas/physiopathology , Pancreatic Neoplasms/complications , Pancreatic Neoplasms/surgery , Positron-Emission Tomography , Radiopharmaceuticals/pharmacokinetics , Retrospective Studies , Sirolimus/therapeutic use , Sulfonylurea Receptors/genetics , Tissue Distribution
6.
Neoplasma ; 67(3): 450-460, 2020 May.
Article in English | MEDLINE | ID: mdl-32122145

ABSTRACT

Mitochondria are highly dynamic organelles involved in many cellular functions. Beyond their central role in metabolism, they also take a part in maintaining calcium homeostasis, cell death, immunity, and ROS production. Changes in these functions have been shown to be crucial for the adaptation and survival of cancer cells. Mitochondria, therefore, constitute a promising target for the development of novel anticancer agents. The triphenylphosphonium (TPP+) moiety has been widely used to target molecules into mitochondria. TPP+ derivatives of a variety of conventional cytostatic drugs, natural substances, metformin, antioxidants or a range of newly synthesized molecules have shown promising results against cancer cells. In this review, we discuss biochemical differences between cancer cells and normal cells with a specific focus on mitochondria, and how mitochondrially targeted molecules can be used to selectively affect mitochondrial function in normal and cancer cells. We summarize the published data on mitochondrially targeted anticancer agents and propose future research avenues.


Subject(s)
Antineoplastic Agents/therapeutic use , Mitochondria/drug effects , Neoplasms/drug therapy , Humans , Organophosphorus Compounds
7.
Physiol Res ; 69(1): 33-48, 2020 02 19.
Article in English | MEDLINE | ID: mdl-31854191

ABSTRACT

Granulosa cells (GCs) are somatic cells essential for establishing and maintaining bi-directional communication with the oocytes. This connection has a profound importance for the delivery of energy substrates, structural components and ions to the maturing oocyte through gap junctions. Cumulus cells, group of closely associated GCs, surround the oocyte and can diminished the effect of harmful environmental insults. Both GCs and oocytes prefer different energy substrates in their cellular metabolism: GCs are more glycolytic, whereas oocytes rely more on oxidative phosphorylation pathway. The interconnection of these cells is emphasized by the fact that GCs supply oocytes with intermediates produced in glycolysis. The number of GCs surrounding the oocyte and their age affect the energy status of oocytes. This review summarises available studies collaboration of cellular types in the ovarian follicle from the point of view of energy metabolism, signaling and protection of toxic insults. A deeper knowledge of the underlying mechanisms is crucial for better methods to prevent and treat infertility and to improve the technology of in vitro fertilization.


Subject(s)
Granulosa Cells/metabolism , Oocytes/growth & development , Animals , Antioxidants/metabolism , Carbohydrate Metabolism , Energy Metabolism , Female , Granulosa Cells/drug effects , Hazardous Substances/toxicity , Humans , Lipid Metabolism , Oocytes/metabolism , Reactive Oxygen Species/metabolism
8.
Klin Onkol ; 32(3): 211-213, 2019.
Article in English | MEDLINE | ID: mdl-31216854

ABSTRACT

BACKGROUND: Hyperthermic isolated limb perfusion uses therapeutic effect of hyperthermia in the bounded compartment of the limb together with increased concentration of chemotherapy effect than what would be achieved in systemic application. Gold standard was melphalan (Alkeran) in combination with tasonermin (Beromun, tumor necrosis factor alpha). The efficacy of this combination has been demonstrated in limb soft tissue sarcomas and in patients with limb isolated bulky disease of malignant melanoma. CASE: We describe a case of a 65-year-old female patient with undifferentiated spindle-cell sarcoma treated by a multidisciplinary team at the 2nd Surgical Clinic of Cardiovascular Surgery and Clinic of Oncology General University Hospital in Prague and at the Department of Orthopaedics Na Bulovce Hospital with the aim of preserving the limb despite the advanced disease. The patient underwent hyperthermic isolated limb perfusion with tasonermin and melphalan with partial response on magnetic resonance imaging. Subsequent wide resection was done with complete pathological remission according to histological examination maintaining a fully functional limb. The patient is followed without signs of recurrence. CONCLUSION: Hyperthermic isolated limb perfusion with tasonermin and melphalan is an important part of a multimodal approach in the treatment of extremity sarcomas with a high percentage of responses that increase the percentage of limbs retaining resections. Multidisciplinary team should consider this option in patients with localized limb sarcomas and should be performed in specialized centers with experience in this procedure. This work was supported by project Progres Q28-LF1. The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers.


Subject(s)
Chemotherapy, Cancer, Regional Perfusion/methods , Hyperthermia, Induced/methods , Sarcoma/therapy , Aged , Humans , Lower Extremity , Magnetic Resonance Imaging , Melphalan/administration & dosage , Neoadjuvant Therapy , Sarcoma/diagnostic imaging , Sarcoma/pathology , Tumor Necrosis Factor-alpha/administration & dosage
9.
Rozhl Chir ; 97(3): 139-144, 2018.
Article in English | MEDLINE | ID: mdl-29589458

ABSTRACT

Minimally invasive techniques have now become standard for the treatment of many surgical conditions in children. There are a few studies that describe the utility of laparoscopy in BAT in children. In this article, we describe the complete laparoscopic surgical treatment of two patients after a single blunt abdominal trauma, both with bowel perforation. In both cases, the perforation was identified and closed, one laparoscopically with an ongoing suture, the second jejune perforation was closed by laparoscopic-assisted techniques. Both patients had an uneventful postoperative recovery. Therapeutic laparoscopic treatment of patients with upper gastrointestinal perforation is feasible. We hypothesize, that diagnostic laparoscopy provides important information for the treatment of children with abdominal trauma and is accompanied by improved diagnostic accuracy, reduction of nontherapeutic laparotomy rates, and a reduction of morbidity. Minimally invasive surgery in children after BAT is suitable for hemodynamic stable patients, could improve pain scores, cosmetic effect, shorter hospital stays, shorter operative times and shorter return to school/activities. However, at any point in the patients care, in case the unstable hemodynamic is encountered, exploratory laparotomy is the procedure of choice.Key words: miniinvasive surgery blunt abdominal trauma - laparoscopy bowel perforation.


Subject(s)
Abdominal Injuries , Intestinal Perforation , Laparoscopy , Wounds, Nonpenetrating , Abdominal Injuries/complications , Abdominal Injuries/surgery , Child , Humans , Intestinal Perforation/etiology , Intestinal Perforation/surgery , Laparotomy , Retrospective Studies , Wounds, Nonpenetrating/complications , Wounds, Nonpenetrating/surgery
10.
Klin Onkol ; 30(3): 213-219, 2017.
Article in Czech | MEDLINE | ID: mdl-28612619

ABSTRACT

BACKGROUND: The authors present a technical variation of the standard cannulation for cardiopulmonary bypass perfusion during hyperthermic isolated limb perfusion (ILP) procedures in selected patients with unresectable soft tissue sarcoma or malignant melanoma. PATIENTS: Of 55 ILP procedures performed at our institution since the procedure was established in 2009, nine were performed at the upper extremity. Standard single venous cannulation was used in five cases, and extended, double venous cannulation in the last four. The standard technique for brachial vein cannulation in a small compartment of the upper extremity entails a problematic and longer perfusion of the upper extremity. This is due to the lower flow rate in the venous system and relatively large surface area with respect to weight. We present a simple technique based on a "Y" cannulation of the venous system via the deep brachial vein and superficial venous system via the basilic vein, delivering a 20% increase in flow rate in the extracorporeal circulation. Faster heating of the upper extremity and a stable thermal environment throughout upper-extremity ILP are essential for successful treatment. CONCLUSION: Extended technique of venous cannulation for extracorporeal circulation setting, due to their advantages, became standard in the upper limb ILP procedure at our institution.Key words: isolated limb perfusion - malignant melanoma - soft tissue sarcoma - upper limb - extracorporeal circulation The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers.Submitted: 8. 1. 2017Accepted: 15. 1. 2017.


Subject(s)
Chemotherapy, Cancer, Regional Perfusion/methods , Melanoma/drug therapy , Sarcoma/drug therapy , Skin Neoplasms/drug therapy , Tumor Necrosis Factor-alpha/administration & dosage , Arm , Humans , Melanoma, Cutaneous Malignant
11.
Eur J Clin Nutr ; 71(5): 594-601, 2017 05.
Article in English | MEDLINE | ID: mdl-28145418

ABSTRACT

BACKGROUND/OBJECTIVES: Branched chain amino acids (BCAA) are among nutrients strongly linked with insulin sensitivity (IS) measures. We investigated the effects of a chronic increase of BCAA intake on IS in two groups of healthy subjects differing in their basal consumption of BCAA, that is, vegans and omnivores. SUBJECTS/METHODS: Eight vegans and eight matched omnivores (five men and three women in each group) received 15 g (women) or 20 g (men) of BCAA daily for 3 months. Anthropometry, blood analyses, glucose clamp, arginine test, subcutaneous abdominal adipose tissue (AT) and skeletal muscle (SM) biopsies (mRNA levels of selected metabolic markers, respiratory chain (RC) activity) were performed at baseline, after the intervention and after a 6 month wash-out period. RESULTS: Compared with omnivores, vegans had higher IS at baseline (GIR, glucose infusion rate: 9.6±2.4 vs 7.1±2.4 mg/kg/min, 95% CI for difference: 0.55 to 5.82) that declined after the intervention and returned to baseline values after the wash-out period (changes in GIR with 95% CI, 3-0 months: -1.64 [-2.5; -0.75] and 9-3 months: 1.65 [0.75; 2.54] mg/kg/min). No such change was observed in omnivores. In omnivores the intervention led to an increased expression of lipogenic genes (DGAT2, FASN, PPARγ, SCD1) in AT. SM RC activity increased in both groups. CONCLUSIONS: Negative impact of increased BCAA intake on IS was only detected in vegans, that is, subjects with low basal amino acids/BCAA intake, which appear to be unable to induce sufficient compensatory changes within AT and SM on a BCAA challenge.


Subject(s)
Amino Acids, Branched-Chain/administration & dosage , Blood Glucose/metabolism , Dietary Exposure/adverse effects , Vegans , Adult , Amino Acids, Branched-Chain/blood , Anthropometry , Diet , Diet, Vegan , Dietary Proteins/administration & dosage , Dose-Response Relationship, Drug , Exercise , Female , Glucose Clamp Technique , Humans , Insulin/blood , Insulin Resistance , Male , Muscle, Skeletal/drug effects , Muscle, Skeletal/metabolism , Prospective Studies , Surveys and Questionnaires , Young Adult
12.
Klin Onkol ; 29(5): 375-379, 2016.
Article in Czech | MEDLINE | ID: mdl-27739318

ABSTRACT

BACKGROUND: Hyperthermic isolated limb perfusion is used to treat irresectable extremity malignancies. It is based on the following principle - the perfusion of the extremity is isolated from systemic circulation and connected to an extra-corporal circuit via which a very high concentration of a chemotherapeutic agent is administered into the blood compartment of the extremity. In some cases, treatment efficiency can be improved using tasonermin (a TNF-α agent). By itself, tasonermin can cause severe health complications in patients if leakage into systemic circulation results in a level that exceeds the maximally tolerated dose. Therefore, it is important to monitor for leakage during the whole operation. METHOD: Leakage monitoring was performed by a nuclear medicine method based on the measurement of activity of a gamma-emitting radiotracer detected by a scintillation probe located over the heart. An amount of radiotracer that resulted in a basal level of measured signal was first administered into the systemic circuit followed by the administration of a second, one order of magnitude higher amount of radiotracer into the perfusion circuit. Leakage, when it occurred, increased the count rate detected over the heart, and the mathematical relation between leakage level and count rate increase was derived. RESULTS: In our department, the method was tested and optimized during isolated limb perfusion without using a TNF-α agent. Then, accreditation for the use of TNF-α was granted. Since then, the method has been used to monitor leakage in all cases of isolated limb perfusion with TNF-α. All isolated limb perfusion operations with TNF-α passed without complications. The radiation burden was almost negligible for both the patient and medical staff. CONCLUSION: The method described in this report represents a reliable method for perfusion leakage monitoring when using TNF-α in our department.Key words: perfusion - isolated limb - TNF-α - leakage - monitoring - nuclear medicine - radiopharmaceuticalsThe authors declare they have no potential confl icts of interest concerning drugs, products, or services used in the study.The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers.Submitted: 16. 6. 2016Accepted: 21. 6. 2016.


Subject(s)
Chemotherapy, Cancer, Regional Perfusion , Extravasation of Diagnostic and Therapeutic Materials/diagnostic imaging , Extremities/diagnostic imaging , Hypothermia, Induced , Neoplasms/diagnostic imaging , Tumor Necrosis Factor-alpha/metabolism , Antineoplastic Agents/therapeutic use , Combined Modality Therapy , Extravasation of Diagnostic and Therapeutic Materials/metabolism , Extremities/pathology , Humans , Neoplasms/pathology , Neoplasms/therapy , Prognosis , Radionuclide Imaging , Radiopharmaceuticals/metabolism , Tumor Necrosis Factor-alpha/administration & dosage
13.
Poult Sci ; 95(7): 1693-1701, 2016 Jul 01.
Article in English | MEDLINE | ID: mdl-26994202

ABSTRACT

In practice, goose eggs are increasingly used and, therefore, the rheological properties have to be known for processing. The eggs of geese (Landes Goose, Anser anser f. domestica) were stored for one, 2, 3, 4, 6, and 8 wk at a constant temperature 4°C. First of all, the egg quality parameters were described in terms of egg weight, egg weight loss, egg shape index, yolk height, albumen height, yolk index, albumen index, and Haugh units. In the next step the rheological behavior of liquid egg products (egg yolk, albumen, and whole liquid egg) was studied using a concentric cylinder viscometer. Flow curves of all liquid egg products exhibited non-Newtonian shear thinning behavior. This behavior can be described using the Herschel-Bulkley model and for technical application using the Ostwald-de Waele model. The effect of the storage duration on the rheological behavior is different for the different liquid egg products. With the exception of very low shear rates, the viscosity of the egg yolk as well as of the whole liquid egg decreases with storage time. At lower shear rates there is a tendency toward increased albumen viscosity with storage duration. The storage duration also affects the mechanical properties of the eggshell membrane. This effect has been evaluated in terms of the ultimate tensile strength, fracture strain, and fracture toughness. All these parameters increased with the loading rate, but decreased during the egg storage. These mechanical phenomena should be respected, namely in the design of the egg model for the numerical simulation of the egg behavior under different kinds of the mechanical loading.


Subject(s)
Food Storage , Geese , Ovum/physiology , Animals , Egg Shell/physiology , Rheology , Viscosity
14.
J Biol Phys ; 42(2): 223-33, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26507435

ABSTRACT

The resistance of goose (Anser anser f. domestica) eggs to damage was determined by measuring the average rupture force, specific deformation and rupture energy during their compression at different compression speeds (0.0167, 0.167, 0.334, 1.67, 6.68 and 13.36 mm/s). Eggs have been loaded between their poles (along X axis) and in the equator plane (Z axis). The greatest amount of force required to break the eggs was required when eggs were loaded along the X axis and the least compression force was required along the Z axis. This effect of the loading orientation can be described in terms of the eggshell contour curvature. The rate sensitivity of the eggshell rupture force is higher than that observed for the Japanese quail's eggs.


Subject(s)
Compressive Strength , Eggs , Geese , Materials Testing , Animals , Biomechanical Phenomena , Egg Shell , Surface Properties
15.
Physiol Res ; 65(2): 193-207, 2016 06 20.
Article in English | MEDLINE | ID: mdl-26447514

ABSTRACT

Obesity is often associated with metabolic impairments in peripheral tissues. Evidence suggests an excess of free fatty acids (FFA) as one factor linking obesity and related pathological conditions and the impact of FFA overload on skeletal muscle metabolism is described herein. Obesity is associated with dysfunctional adipose tissue unable to buffer the flux of dietary lipids. Resulting increased levels and fluxes of plasma FFA lead to ectopic lipid deposition and lipotoxicity. FFA accumulated in skeletal muscle are associated with insulin resistance and overall cellular dysfunction. Mechanisms supposed to be involved in these conditions include the Randle cycle, intracellular accumulation of lipid metabolites, inflammation and mitochondrial dysfunction or mitochondrial stress. These mechanisms are described and discussed in the view of current experimental evidence with an emphasis on conflicting theories of decreased vs. increased mitochondrial fat oxidation associated with lipid overload. Since different types of FFA may induce diverse metabolic responses in skeletal muscle cells, this review also focuses on cellular mechanisms underlying the different action of saturated and unsaturated FFA.


Subject(s)
Adipose Tissue/metabolism , Energy Metabolism/physiology , Fatty Acids, Nonesterified/metabolism , Muscle, Skeletal/metabolism , Obesity/metabolism , Adipose Tissue/pathology , Animals , Humans , Muscle, Skeletal/pathology , Obesity/pathology
16.
Adv Exp Med Biol ; 837: 49-56, 2015.
Article in English | MEDLINE | ID: mdl-25315625

ABSTRACT

Blood gases levels imbalances belong to important factors triggering central nervous system (CNS) functional disturbances. Hypoxia can be illness-related, like in many COPD patients, or it may be caused by broad range of external or iatrogenic factors - including influence of drugs depressing respiration, failure to keep the patient's prosthesis-supported airways patent, or a mistake in the operation of medical equipment supporting patient's respiration. Hypoxia, especially when it is not accompanied by rapid carbon dioxide retention, can go unnoticed for prolonged times, deepening existing CNS disorders, sometimes rapidly triggering their manifestation, or evoking quite new conditions and symptoms - like anxiety, agitation, aggressive behavior, euphoria, or hallucinations. Those, in turn, often result in situations raising interest in law enforcement institutions which need forensic medicine specialist's assistance and opinion. The possibility of illness or drug-related hypoxia, especially in terminal patients, is used to raise questions about the patients' ability to properly express their will in the way demanded by law - it also must be considered as a factor limiting the patients' responsibility in case they commit crimes. The possibility of hallucinations in hypoxia patients limits their credibility as witnesses or even their ability to report crime or sexual abuse they have been subjected to.


Subject(s)
Aggression/physiology , Brain/physiopathology , Forensic Medicine/legislation & jurisprudence , Hypoxia/physiopathology , Mental Competency , Psychomotor Agitation/etiology , Adult , Aged , Airway Obstruction/complications , Airway Obstruction/physiopathology , Airway Obstruction/psychology , Anesthesiology , Anesthetics/adverse effects , Decision Making/drug effects , Fatal Outcome , Female , Hallucinations/diagnosis , Humans , Hypnotics and Sedatives/adverse effects , Hypoxia/blood , Hypoxia/etiology , Intubation, Intratracheal/adverse effects , Intubation, Intratracheal/instrumentation , Judgment/drug effects , Lung Neoplasms/complications , Male , Multiple Organ Failure/physiopathology , Multiple Organ Failure/therapy , Postoperative Period , Prosthesis Failure , Rape/legislation & jurisprudence , Terminal Care , Volition/drug effects
17.
Endocr Regul ; 48(2): 55-63, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24824800

ABSTRACT

OBJECTIVE: The aim of the present work was to assess the incidence of parathyroid glands hyperplasia or adenoma in patients with various stages of chronic renal insufficiency using 99mTc-methoxyisobutylisonitrile (MIBI) SPECT and 3D subtraction technique with 99mTc-pertechnetate (Tc). SUBJECTS AND METHODS: Sixty one patients underwent hybrid SPECT with low-dose CT of the parathyroid glands and thyroid SPECT scintigraphy. Thirty six patients were with chronic kidney disease (CKD) without renal failure (RF) and 25 patients underwent peritoneal dialysis or hemodialysis. In each patient, two SPECT studies were performed - an early and a late one with low dose of CT with MIBI injection. Additional SPECT was performed on another day with Tc. SPECT studies were evaluated visually using volume rendering method and semi-quantitatively by 3D subtraction of Tc SPECT from early MIBI SPECT. RESULTS: From all 61 patients, 40/61 (66%) findings were positive, 7/61 (12%) inconclusive, and 14/61 (23%) negative. Solitary lesions were detected in 22 patients. More than one lesion was found in 18 patients. CONCLUSION: The incidence of secondary hyperparathyroidism was detected in 40/61 patients (66%) with chronic kidney disease using scintigraphy and 16 patients (40%) from them underwent surgery. MIBI SPECT/low dose CT with 3D dual - tracer subtraction (MIBI-Tc) method is an effective tool for preoperative detection of the parathyroid glands hyperplasia or adenoma.


Subject(s)
Hyperparathyroidism, Secondary/epidemiology , Renal Insufficiency, Chronic/complications , Technetium Tc 99m Sestamibi , Tomography, Emission-Computed, Single-Photon/methods , Adult , Aged , Aged, 80 and over , Female , Humans , Hyperparathyroidism, Secondary/diagnostic imaging , Hyperparathyroidism, Secondary/etiology , Imaging, Three-Dimensional , Incidence , Male , Middle Aged , Radiation Dosage , Subtraction Technique , Young Adult
18.
Bratisl Lek Listy ; 115(2): 91-7, 2014.
Article in English | MEDLINE | ID: mdl-24601703

ABSTRACT

BACKGROUND: Folic acid deficiency plays a central role in the aetiology of many congenital anomalies including neural tube defects. Protective effect of folic acid on embryo may be acquired only if taken periconceptionally. OBJECTIVES: The aim of the study was to investigate the awareness about folic acid among women of childbearing age in Bratislava, Slovakia. METHODS: There were 130 respondents involved in the research (106 pregnant women, 24 female students of medical faculty). Using questionnaire we acquired following data: pregnancy details, interest in diet before and during pregnancy, recommendations regarding nutrition and supplementation pre- and post-conception, knowledge about folic and other acid in 2004 and 2009. RESULTS: More than half of the respondents knew the sources of folic acid. The interest in the nutrition facts of the food dropped from 91 % to 58.5 %. The number of pregnant women advised about correct nutrition and folic acid supplementation before and during pregnancy increased from 16 % to 37 %. Planning the next gravidity with folic acid supplementation became greater than 21 % (38 % in 2009). Nevertheless, only 46 % of these women believed that proper food content with folic acid may prevent congenital anomalies. In a group of students planning to take folic acid periconceptionally the number raised up to 62.5 %. CONCLUSION: The results revealed low knowledge about the effect of folic acid on developing embryo among women of childbearing age. Effective intervention programs are needed with the aim to improve periconceptional intake of folic acid in 2004 and 2009. The results in both periods show low knowledge about this essential vitamin (Tab. 1, Fig. 8, Ref. 31).


Subject(s)
Folic Acid/administration & dosage , Health Knowledge, Attitudes, Practice , Neural Tube Defects/prevention & control , Prenatal Care , Vitamin B Complex/administration & dosage , Adult , Female , Folic Acid/therapeutic use , Humans , Population Surveillance , Pregnancy , Slovakia , Surveys and Questionnaires , Vitamin B Complex/therapeutic use
19.
Bratisl Lek Listy ; 115(1): 49-53, 2014.
Article in English | MEDLINE | ID: mdl-24471904

ABSTRACT

BACKGROUND: Biliary atresia is a progressive cholangiopathy in neonates of unknown origin. Surgical intervention - Kasai portoenterostomy - is the only treatment possible. However, only liver transplantation can be considered a definitive solution even in cases of favourable post-operative course, i.e., after bile passage has been recreated. OBJECTIVES: The authors set out to identify ways to optimize the operative treatment in biliary atresia patients. In particular, their objective was to identify a suitable bile derivation area outside porta hepatis, thereby simplifying the surgical procedure of the following liver transplantation. METHODS: The research was conducted from 2006 to 2010 on a set of 30 corrosive casts prepared by the Institute of Anatomy, Medical Faculty, Comenius University Bratislava. The research consisted of an analysis of individual tubular structures of the liver parenchyma, particularly the bile vessels. The authors explored the latter's position and branching out, as well as their relationships in different segments, and their availability in surgical exploration. RESULTS: The analysis of the corrosive casts resulted in selecting an area in liver segments II and III suitable for creating a new type of hepatoenterostomy. The area is sufficiently distant from porta hepatis, conveniently accessible to the surgeon, and has a broad bile duct branch. This type of anastomosis would preserve the anatomic situation in the porta hepatis area intact for the following transplantation. CONCLUSION: While the results of the experiment warrant some optimism, authors will have to wait until this type of derivation operation is applicable in practice. The authors continue their research by performing anastomosis in an animal model (Fig. 5, Ref. 18)


Subject(s)
Biliary Atresia/surgery , Portoenterostomy, Hepatic/trends , Animals , Biliary Atresia/pathology , Humans , Infant, Newborn , Liver Transplantation , Portoenterostomy, Hepatic/methods , Treatment Outcome
20.
Eur J Clin Nutr ; 67(12): 1310-5, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24149445

ABSTRACT

BACKGROUND/OBJECTIVES: Vegans have a lower incidence of insulin resistance (IR)-associated diseases and a higher insulin sensitivity (IS) compared with omnivores. The aim of this study was to examine whether the higher IS in vegans relates to markers of mitochondrial biogenesis and to intramyocellular lipid (IMCL) content. SUBJECTS/METHODS: Eleven vegans and 10 matched (race, age, sex, body mass index, physical activity and energy intake) omnivorous controls were enrolled in a case-control study. Anthropometry, bioimpedance (BIA), ultrasound measurement of visceral and subcutaneous fat layer, parameters of glucose and lipid homeostasis, hyperinsulinemic euglycemic clamp and muscle biopsies were performed. Citrate synthase (CS) activity, mitochondrial DNA (mtDNA) and IMCL content were assessed in skeletal muscle samples. RESULTS: Both groups were comparable in anthropometric and BIA parameters, physical activity and protein-energy intake. Vegans had significantly higher glucose disposal (M-value, vegans 8.11±1.51 vs controls 6.31±1.57 mg/kg/min, 95% confidence interval: 0.402 to 3.212, P=0.014), slightly lower IMCL content (vegans 13.91 (7.8 to 44.0) vs controls 17.36 (12.4 to 78.5) mg/g of muscle, 95% confidence interval: -7.594 to 24.550, P=0.193) and slightly higher relative muscle mtDNA amount (vegans 1.36±0.31 vs controls 1.13±0.36, 95% confidence interval:-0.078 to 0.537, P=0.135). No significant differences were found in CS activity (vegans 18.43±5.05 vs controls 18.16±5.41 µmol/g/min, 95% confidence interval: -4.503 to 5.050, P=0.906). CONCLUSIONS: Vegans have a higher IS, but comparable mitochondrial density and IMCL content with omnivores. This suggests that a decrease in whole-body glucose disposal may precede muscle lipid accumulation and mitochondrial dysfunction in IR development.


Subject(s)
Diet, Vegetarian , Insulin Resistance , Mitochondria, Muscle/ultrastructure , Muscle, Skeletal/ultrastructure , Adult , Anthropometry , Biopsy , Blood Glucose/analysis , Diet , Fasting , Female , Humans , Insulin/blood , Lipids/analysis , Lipids/blood , Male , Mitochondria, Muscle/physiology , Muscle Cells/chemistry
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