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1.
J Physiol Pharmacol ; 73(5)2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36942807

RESUMO

Hepcidin is a primary regulator of iron metabolism in the human body. By promoting ferroportin degradation, hepcidin reduces intestinal iron absorption and its release from intracellular stores. In the course of pregnancy, gradually declining hepcidin concentrations encourage placental iron transfer, thereby providing the appropriate amount of iron for fetal development. Hence, we aimed to investigate changes in maternal and cord blood hepcidin and iron metabolism parameters in normal-weight (n=17) and obese (n=17) gestating women, as well as gravid women with a history of hypothyroidism following the restoration of euthyroidism (n=17). All blood samples were taken on the day of delivery, and ELISA kits were used for measurements. A significant increase in maternal hepcidin concentration was observed in obese pregnant women, compared to normal-weight controls (29.53±4.20 ng/mL vs. 25.69±5.70 ng/mL; P<0.05). However, only a slight, insignificant tendency for lower hepcidin was noted in the hypothyroid group, compared to the healthy controls (23.10±6.00 ng/mL vs. 25.69±5.70 ng/mL; P=NS). Moreover, decreased maternal free triiodothyronine, triiodothyronine, free thyroxine, and ferritin levels were revealed in the hypothyroid group, compared to the normal-weight individuals (P<0.05). Furthermore, positive correlations between maternal hepcidin and the majority of maternal thyroid hormones were found, with a most potent relation to FT3 (r=0.40; P<0.01). Interestingly, no alterations of thyroid hormones and iron metabolism parameters were noticed in cord blood in any of the subgroups. In summary, pre-pregnancy obesity is associated with elevated maternal hepcidin, albeit no signs of lowered cord blood iron status were shown. Medical history of hypothyroidism following the restoration of euthyroidism does not substantially influence maternal nor cord blood hepcidin concentration, as well as fetal iron homeostasis, even though free thyroid hormone levels correlate with maternal hepcidin.


Assuntos
Sangue Fetal , Hipotireoidismo , Feminino , Gravidez , Humanos , Sangue Fetal/metabolismo , Projetos Piloto , Tri-Iodotironina/metabolismo , Placenta/metabolismo , Ferro/metabolismo , Obesidade/metabolismo , Hipotireoidismo/metabolismo
2.
Eur Rev Med Pharmacol Sci ; 25(19): 5993-6002, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34661259

RESUMO

OBJECTIVE: Kisspeptin (KP) is a major regulator of reproductive functions. It has also been shown to be involved in the metabolic changes associated with obesity. According to the well-established concept of prenatal programming, environmental factors can influence physiological and behavioral systems at the early stages of development. Thus, we hypothesized that in pregnant women, obesity can be associated with alterations in the levels of KP. We also assumed that the observed changes in obese mothers' blood (MB) would be reflected in the umbilical cord blood (CB). MATERIALS AND METHODS: We collected MB and CB from obese and nonobese women and analyzed the differences in metabolic and hormonal profiles, including KP concentration, using commercially available assays. RESULTS: We found that the level of KP was increased in the MB and CB of obese patients compared to nonobese subjects (p<0.05). A strong correlation was observed between the concentration of KP in MB and CB (r=0.8343; p<0.01). Moreover, we detected that the differences in the adipokine profile observed in the MB were not reflected in CB. CONCLUSIONS: Our results indicate that blood KP concentration can serve as a valuable marker in pregnant women. However, further studies are needed to understand the alterations of this peptide in obese pregnant woman and their potential effects on offspring.


Assuntos
Sangue Fetal/metabolismo , Kisspeptinas/sangue , Obesidade/epidemiologia , Adulto , Feminino , Humanos , Recém-Nascido , Masculino , Mães , Obesidade/sangue , Projetos Piloto , Gravidez
3.
J Physiol Pharmacol ; 72(1)2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34099582

RESUMO

Normal iron metabolism is an inherent feature of maintaining homeostasis. There is a wide range of iron disorders, which arise from iron deficiency or overload. In addition, disturbances in iron metabolism are observed in the course of numerous chronic diseases. Since iron is an essential constituent of hemoglobin, different types of anemia are clinical manifestations of both iron deficit or excess. This seemingly contradictory statement may be elucidated by the presence of hepcidin. Hepcidin is a primary regulator of iron metabolism in the human body. By promoting ferroportin degradation, hepcidin decreases the amount of iron in the circulation due to iron sequestration in the tissues and reduced intestinal absorption. Altered hepcidin concentration is a compensatory mechanism aimed at restoring iron homeostasis in various physiologic states, including pregnancy. However, hepcidin may also participate in the pathophysiologic background of hereditary hemochromatosis, anemia of chronic disease, myelodysplastic syndromes or ß-thalassemia. Moreover, hepcidin is an acute-phase protein involved in innate immunity reactions. In our paper, we provide a comprehensive review of the physiologic and pathophysiologic functions of hepcidin. We present current knowledge on the structure, physiologic role and its expression control, as well as demonstrate the contribution of hepcidin in a state of illness. We also summarize the significance of hepcidin in normal and complicated pregnancy. Emphasizing the alterations in hepcidin upon treatment of specific diseases and their position in certain pathomechanisms, we support clinicians with practical aspects related to hepcidin.


Assuntos
Hepcidinas/metabolismo , Distúrbios do Metabolismo do Ferro/fisiopatologia , Ferro/metabolismo , Animais , Humanos , Deficiências de Ferro/fisiopatologia , Sobrecarga de Ferro/fisiopatologia
4.
Benef Microbes ; 12(3): 249-257, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33765904

RESUMO

The aim of the study was to determine effects of administration of simethicone and a multi-strain synbiotic on the crying behaviour of colicky babies. The study design consisted of an open-label, two parallel treatment group study involving 87 infants aged 3-6 weeks with infantile colic (defined as crying episodes lasting 3 or more hours per day and occurring at least 3 days per week within 3 weeks prior to enrolment) randomly, unequally [1:1.5] assigned to receive simethicone (n=33) or a multi-strain synbiotic (n=54) orally for 4 weeks. The multi-strain synbiotic contained Lactobacillus acidophilus LA-14, Lacticaseibacillus casei R0215, Lacticaseibacillus paracasei Lp-115, Lacticaseibacillus rhamnosus GG, Ligilactobacillus salivarius Ls-33, Bifidobacterium lactis Bl-04, Bifidobacterium bifidum R0071, Bifidobacterium longum R0175 and fructooligosaccharides). Primary outcome measures were the responder rates (effect ≥50% reduction from baseline) of the measures 'crying days last 3 weeks', 'average evening crying duration last 3 weeks' and 'reduction of average number of crying phases per day last three weeks' at the end of treatment. The study is registered at ClinicalTrials.gov under NCT04487834. Significantly higher responder rates (effect ≥50% reduction from baseline) of the multi-strain synbiotic compared to simethicone were found for the measures 'crying days last 3 weeks' (72% vs 18%, P<0.0001) and 'average evening crying duration last 3 weeks' (85% vs 39%, P=0.0001). No significant difference was found for the measure 'reduction of average number of crying phases per day last three weeks' (50% vs 42%, P=0.4852). No adverse effects were reported for the two treatment groups. Based on these results, the multi-strain synbiotic can be considered as an interesting therapeutic possibility for the treatment of infantile colic, worthwhile to be investigated further in non-clinical and clinical studies.


Assuntos
Bactérias , Cólica/terapia , Simeticone/administração & dosagem , Simbióticos/administração & dosagem , Antiespumantes/administração & dosagem , Bactérias/classificação , Choro/fisiologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Resultado do Tratamento
5.
J Physiol Pharmacol ; 72(5): 731-739, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-35158335

RESUMO

To meet energy demands for lactogenesis and to sustain homeostatic conditions post-partum, the organism of breastfeeding mother undergoes combined endocrine and metabolic regulation. The main objective of this study was to determine basal serum concentrations of hormones involved in the maintenance and defense of energy balance in breastfeeding (BF) and formula feeding (FF) mothers. Twenty healthy exclusively breastfeeding mothers at 3rd month of lactation (EBF3), 17 healthy partially breastfeeding at 6th month of lactation (PB6) and 17 healthy FF mothers participated in this study. Fasting serum prolactin (PRL), acylated ghrelin (aGhr), total ghrelin (tGhr), leptin, adiponectin, insulin, and cortisol were determined for all study participants and correlations between studied parameters were calculated for BF women. We found significantly lower basal insulin (p = 0.0048) and cortisol (p = 0.0002) and significantly elevated basal prolactin (p = 0.0020) and leptin (p = 0.0416) in BF when compared with FF women. The differences were not associated with the duration of lactation (3 vs. 6 months), except for PRL, which was highest in EBF3. Levels of Ghr and adiponectin did not differ between study groups. In the BF group, the negative correlations were found between: aGhr and insulin, aGhr and adiponectin, leptin and cortisol, leptin and adiponectin, insulin and adiponectin, cortisol and adiponectin. Positive associations were noted between: insulin and leptin, leptin and aGhr, PRL and leptin, PRL and aGhr. Leptin and insulin correlated positively, whereas adiponectin negatively with BMI. These data may suggest that EBF3 and PB6 as compared with FF mothers, exhibit hormonal regulation which tends to be more advantageous for their metabolic profile and is not related to the duration of breastfeeding within the first 6 months of lactation.


Assuntos
Aleitamento Materno , Mães , Adiponectina , Feminino , Grelina , Homeostase , Humanos , Insulina , Lactação , Leptina
6.
J Physiol Pharmacol ; 70(5)2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32009627

RESUMO

Recreational winter swimming in cold sea water evokes body responses to regularly repeated cold water immersion. However, the understanding of adaptive changes is still limited and data regarding very short-term exposure to severe cold stress are scarce. The purpose of the study was to examine the effects of regular active cold water exposure on resting blood elements and erythropoietin in male and female cold water swimmers (CWSs). Thirty four healthy subjects (18 men and 16 women) aged 50.0 ± 12.2 years were swimming in cold sea water during winter season at least twice a week. The average water temperature was 9.5°C in October, 1.0°C in January and 4.4°C at the end of April. Fasting blood samples were taken within the first weeks of October, January and April. Serum erythropoietin (EPO), complete blood count (CBC) including evaluation of: red blood cells (RBC count, hemoglobin, hematocrit and RBC indices), white blood cells (WBC count with WBC differential), platelets (PLT count), serum folate and serum immunoglobulins (IgG, IgA, IgM) were determined. Between October and April an increase was observed in the following parameters: RBC (from 4.8 x 1012/L to 5.2 x 1012/L, P < 0.001), hemoglobin (from 8.6 mmol/L to 9.4 mmol/L, P < 0.001), MCH (from 1.8 fmol to 1.9 fmol, P = 0.003), MCHC (from 19.9 mmol/L to 20.6 mmol/L, P < 0.001), EPO (from 6.3 IU/L to 8.1 IU/L, P = 0.001). At the same time decreased concentrations of PLT (from 249.9 x 109/L to 221.6 x 109/L, P = 0.005), folate (from 10.5 ng/mL to 7.4 ng/mL, P < 0.001) and immunoglobulins (IgG: from 11.8 g/L to 10.9 g/L, P < 0.001; IgA: from 2.5 g/L to 2.2 g/L, P < 0.001; IgM: from 0.9 g/L to 0.8 g/L, P < 0.001). Statistically significant changes in EPO and PLT values were noted only in female CWSs. We conclude that regular cold water swimming induces adaptive changes in the resting blood elements and EPO concentrations which are more evident in female organism.


Assuntos
Eritropoetina/metabolismo , Descanso/fisiologia , Natação/fisiologia , Contagem de Células Sanguíneas/métodos , Plaquetas/metabolismo , Temperatura Baixa , Eritrócitos/fisiologia , Feminino , Ácido Fólico/metabolismo , Hematócrito/métodos , Hemoglobinas/metabolismo , Humanos , Imunoglobulinas/metabolismo , Masculino , Pessoa de Meia-Idade , Estações do Ano , Água/metabolismo
7.
Physiol Res ; 67(1): 45-56, 2018 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-29137471

RESUMO

Spexin (SPX) and kisspeptin (KISS) are novel peptides relevant in the context of regulation of metabolism, food intake, puberty and reproduction. Here, we studied changes of serum SPX and KISS levels in female non-obese volunteers (BMI<25 kg/m(2)) and obese patients (BMI>35 kg/m(2)). Correlations between SPX or KISS with BMI, McAuley index, QUICKI, HOMA IR, serum levels of insulin, glucagon, leptin, adiponectin, orexin-A, obestatin, ghrelin and GLP-1 were assessed. Obese patients had lower SPX and KISS levels as compared to non-obese volunteers (SPX: 4.48+/-0.19 ng/ml vs. 6.63+/-0.29 ng/ml; p<0.001, KISS: 1.357+/-0.15 nmol/l vs. 2.165+/-0.174 nmol/l; p<0.01). SPX negatively correlated with BMI, HOMA-IR, insulin, glucagon, active ghrelin and leptin. Positive correlations were found between SPX and QUICKI index, McAuley index, serum levels of obestatin, GLP-1 and adiponectin and orexin-A Serum KISS negatively correlated with BMI, HOMA-IR, serum levels of insulin, glucagon, active ghrelin and leptin. KISS positively correlated with QUICKI index, McAuley index and adiponectin. In summary, SPX and KISS show negative correlations with obesity, insulin resistance indices, and hormones known to affect insulin sensitivity in females. Both, SPX and KISS could be therefore relevant in the pathophysiology of obesity and insulin resistance.


Assuntos
Resistência à Insulina/fisiologia , Kisspeptinas/sangue , Obesidade/sangue , Hormônios Peptídicos/sangue , Adulto , Biomarcadores/sangue , Feminino , Humanos , Pessoa de Meia-Idade , Obesidade/diagnóstico
8.
J Physiol Pharmacol ; 68(4): 539-546, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29151070

RESUMO

Recent studies indicate disruptions to the circadian system in brain injury and neurodegeneration. The results, however, are often not consistent and limited by measurement of only one circadian marker and by infrequent sampling rates. In this study, we examined diurnal rhythmicity in different stages of Huntington (HD) disease and in patients with acute moderate ischemic stroke (AIS) outside the retinohypothalamic pathway by evaluating serum concentrations of melatonin and cortisol at twelve timepoints. All study participants were subjected to the same study protocol of 12-hour light/dark cycle and controlled room conditions. Using cosinor analysis of data and comparing the results with the controls we found melatonin phase delay with lowered amplitude and mesor in stage III HD patients. These changes coexisted with phase advanced rhythm and elevated values of mesor and amplitude for cortisol. Early and mid-stages of HD showed only a phase advance in cortisol secretion. In AIS the circadian rhythm of serum melatonin was sustained without any phase shift and exhibited more flattened profile (lowered mesor and amplitude values), while advanced rhythm with higher mesor for cortisol was present. In conclusion, 1) abnormal pattern of melatonin release in the late stages of HD and in moderate AIS occurs in conjunction with phase-advanced rhythm of cortisol; 2) changes observed in late stages of HD are similar to those that occur with ageing; 3) brain regions other than the presumptive retinopineal neural pathway may play an important role in the pineal production of melatonin in humans; 4) lesion in extrahypothalamic region is related to the strong adrenal stimulation in response to AIS.


Assuntos
Isquemia Encefálica/fisiopatologia , Ritmo Circadiano/fisiologia , Doença de Huntington/fisiopatologia , Hidrocortisona/metabolismo , Melatonina/metabolismo , Acidente Vascular Cerebral/fisiopatologia , Isquemia Encefálica/metabolismo , Humanos , Doença de Huntington/metabolismo , Masculino , Pessoa de Meia-Idade , Fotoperíodo , Acidente Vascular Cerebral/metabolismo
9.
J Physiol Pharmacol ; 68(6): 887-896, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29550801

RESUMO

It has been proposed that regular cold swimming is associated with health benefits. However, the effect of cold adaptation on particular cardiovascular risk factors, within a single swimming season, remains unknown. Our aim was to evaluate the impact of cold water swimming on the seasonal changes in lipid profile and on apolipoprotein and homocysteine concentration in 34 cold water swimmers (CWS) aged 48 - 68 years. Blood samples were collected at the beginning (October), the middle (January), and the end (April) of the swimming season. Body mass (BM), total cholesterol (TC), high-density lipoprotein (HDL), low-density lipoprotein (LDL), triglycerides (TG), ApoB/ApoA-I ratio, and homocysteine concentrations were evaluated. In October, female CWS showed lower BM (P = 0.01), TG concentrations (P = 0.03), and ApoB/ApoA-I ratios (P = 0.008), and higher HDL (P = 0.01) than in men. Similar trends in BM (P = 0.002), HDL (P = 0.0006), and ApoB/ApoA-I ratio (P = 0.01) were seen in January, and for BM (P = 0.002), TG (P = 0.005), HDL (P = 0.003), and ApoB/ApoA-I (P = 0.01) in April. A decrease in TG concentration between January and April (P = 0.05), lower homocysteine concentration between October and January (P = 0.01), and between October and April (P = 0.001) were documented in CWS. A strong drop in homocysteine concentration was observed in female versus male CWS (P = 0.001 versus P = 0.032), particularly between October and April in women (P = 0.001) and October and January in men (P = 0.05). The ApoB/ApoA-I ratio in female CWS decreased over the season (P = 0.02), particularly between October and January (P = 0.05), and a trend toward the TG concentration to reduce over the swimming season was also observed in female CWS. No beneficial changes were noticed in the control group over the season. Our results suggest that the favorable effect of cold swimming on the cardiovascular risk factors may be gender-dependent; further studies are thus needed to draw a precise conclusion.


Assuntos
Temperatura Baixa , Metabolismo dos Lipídeos , Natação/fisiologia , Idoso , Apolipoproteína A-I/sangue , Apolipoproteína B-100 , Feminino , Homocisteína/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Estações do Ano , Caracteres Sexuais , Água
10.
J Physiol Pharmacol ; 66(3): 367-72, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26084218

RESUMO

We examined an association between ghrelin, including its major isoforms, interleukin-6 (IL-6), body mass index (BMI), and mean arterial pressure (MAP) in male overweight patients with essential hypertension. Twenty hypertensive male patients with newly diagnosed essential hypertension (EH) before starting drug treatment and 22 age-matched healthy controls were enrolled in the study. Fasting total plasma ghrelin (TGhr), acyl ghrelin (AGhr), des-acyl ghrelin (DGhr) and IL-6 were determined and correlations between studied parameters were calculated. We found significantly lower total plasma ghrelin and higher plasma IL-6 in hypertensives when compared with the control. In patients with hypertension the negative correlations were found: between TGhr and BMI, DGhr and BMI, TGhr and MAP, and between DGhr and MAP. IL-6 positively correlated with BMI and MAP in hypertensive subjects. No correlations between all forms of ghrelin and IL-6 were noted. The changes in plasma ghrelin and IL-6 contribute independently to the elevated blood pressure in essential hypertension. Negative correlation of DGhr and MAP may suggest its hemodynamic involvement in regulation of blood pressure.


Assuntos
Grelina/sangue , Hipertensão/sangue , Interleucina-6/sangue , Idoso , Pressão Arterial , Índice de Massa Corporal , Hipertensão Essencial , Humanos , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade
11.
Bioelectrochemistry ; 101: 132-7, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25308935

RESUMO

This paper aims at the presentation of the results of in vitro research on the dielectric properties of the cornea specimen collected from the rats subjected to in vivo hypothermia. The average values of the relative permittivity and dielectric loss are about 40% higher for the hypothermic cornea than those for the normothermic tissue at the same water content of 12% for both samples and at 25°C. Whereas, at 50°C this effect of increase in the dielectric properties of the hypothermic cornea when compared to the normothermic one is observed clearly only in the relative permittivity of about 19%. In the temperature range of 25-50°C, the activation energy of conductivity associated with the release of loosely bound water takes the average values of 45kJ/mol and 30kJ/mol for the normothermic and hypothermic corneas, respectively. The study provided information on dielectric polarization and conductance mechanisms in the cornea which may be helpful in interpreting clinical results of human cornea examination, currently obtained by means of such electrodiagnostic methods as conductive keratoplasty, electroretinography or electrooculography.


Assuntos
Córnea/fisiologia , Hipotermia/fisiopatologia , Animais , Córnea/química , Espectroscopia Dielétrica/métodos , Eletrofisiologia/métodos , Masculino , Ratos Wistar , Temperatura
12.
Spinal Cord ; 53(5): 345-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25420497

RESUMO

STUDY DESIGN: Retrospective study. OBJECTIVES: This study was implemented to detect risk factors for the developing of heterotopic ossifications (HOs) in spinal cord injury (SCI) patients. SETTING: This study was conducted in Murnau, Germany. METHODS: All patients from 2008-2012 with acute SCI were routinely examined by ultrasound of the hips every 2 weeks. The sub group of SCI patients suffering of HO of the hips were extracted and the incidence of developing an HO was calculated. Parameters like age, level of injury, ASIA Impairment Scale (AIS), duration time of accident until diagnosis of HO, Brooker stage, localization of HO (magnetic resonance imaging (MRI)) and symptoms like thrombosis, emboli, decrease of range of motion (ROM), dermal symptoms, swelling, increase in D-Dimere level, were evaluated. Also accompanying injuries of the brain, lung and extremities were recorded. RESULTS: From January 2008 until January 2012, 575 patients with an acute and traumatic SCI were treated in our Department. During this period 32 HOs were detected in the muscles surrounding the hip. In 10 cases a single side and in 22 cases both sides were affected. A total of 26 patients were detected showing up a Brooker 0, two patients Brooker 1, and five patients a Brooker stage >2. The adductor muscles showed an edema in 19 cases and the quadriceps muscles were affected in 15 cases. 26% of all SCI patients showed AIS A status, but in patients who developed HO, 64% have had an AIS A status. 19% of patients with a HO were AIS B and 9.5% showed an AIS C and D. Regarding the level of injury the distribution of patients suffering of HO was comparable to the distribution of SCI patients without HO. In mean HO were detected 9 weeks after SCI and no new HO were found after the 22nd (n=1) week of injury. Clinical symptoms such as swelling, pain, redness or decrease in ROM or increase in D-Dimere levels were seen in 24 cases. Accompanying injuries like brain injury and lung contusions were found in 83% of patients developing HO. The incidence of thrombosis was comparable to SCI patients without HO. One patient with no accompanying injuries or clinical symptoms was detected by routinely performed ultrasound. CONCLUSIONS: The risk of developing HO in patients with traumatic SCI is 5.5% but increases when accompanying injuries of the brain and lung occur. Patients with a neurological status of AIS A must also be quoted as risk patients. When considering the described risk factors and clinical symptoms, 96% of all HO can be detected.


Assuntos
Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Ossificação Heterotópica/etiologia , Radioterapia/efeitos adversos , Traumatismos da Medula Espinal/sangue , Traumatismos da Medula Espinal/radioterapia , Adolescente , Adulto , Idoso , Feminino , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Ossificação Heterotópica/diagnóstico por imagem , Amplitude de Movimento Articular/fisiologia , Estudos Retrospectivos , Fatores de Risco , Ultrassonografia , Adulto Jovem
13.
Med Phys ; 40(11): 111719, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24320427

RESUMO

PURPOSE: To demonstrate the feasibility of portal dosimetry with an amorphous silicon mega voltage imager for flattening filter free (FFF) photon beams by means of the GLAaS methodology and to validate it for pretreatment quality assurance of volumetric modulated arc therapy (RapidArc). METHODS: The GLAaS algorithm, developed for flattened beams, was applied to FFF beams of nominal energy of 6 and 10 MV generated by a Varian TrueBeam (TB). The amorphous silicon electronic portal imager [named mega voltage imager (MVI) on TB] was used to generate integrated images that were converted into matrices of absorbed dose to water. To enable GLAaS use under the increased dose-per-pulse and dose-rate conditions of the FFF beams, new operational source-detector-distance (SDD) was identified to solve detector saturation issues. Empirical corrections were defined to account for the shape of the profiles of the FFF beams to expand the original methodology of beam profile and arm backscattering correction. GLAaS for FFF beams was validated on pretreatment verification of RapidArc plans for three different TB linacs. In addition, the first pretreatment results from clinical experience on 74 arcs were reported in terms of γ analysis. RESULTS: MVI saturates at 100 cm SDD for FFF beams but this can be avoided if images are acquired at 150 cm for all nominal dose rates of FFF beams. Rotational stability of the gantry-imager system was tested and resulted in a minimal apparent imager displacement during rotation of 0.2 ± 0.2 mm at SDD = 150 cm. The accuracy of this approach was tested with three different Varian TrueBeam linacs from different institutes. Data were stratified per energy and machine and showed no dependence with beam quality and MLC model. The results from clinical pretreatment quality assurance, provided a gamma agreement index (GAI) in the field area for six and ten FFF beams of (99.8 ± 0.3)% and (99.5 ± 0.6)% with distance to agreement and dose difference criteria set to 3 mm/3% with 2 mm/2% thresholds, GAI resulted (95.7.0 ± 2.3)% and (97.2 ± 2.1)%. CONCLUSIONS: The GLAaS methodology, introduced in clinical practice for conventional flattened photon beams for machine, IMRT, and RapidArc quality assurance, was successfully adapted for FFF beams of Varian TrueBeam Linac. The detector saturation effects could be eliminated if the portal images acquired at 150 cm for all nominal dose rates of FFF beams.


Assuntos
Radiometria/métodos , Radioterapia de Intensidade Modulada/métodos , Silício/química , Algoritmos , Calibragem , Desenho de Equipamento , Humanos , Aceleradores de Partículas , Fótons , Controle de Qualidade , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Reprodutibilidade dos Testes , Espalhamento de Radiação
14.
Colloids Surf B Biointerfaces ; 109: 143-6, 2013 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-23632462

RESUMO

In this study, we analyzed the effect of water and frequency on the dielectric properties of the nail plate in healthy individuals and in diabetic patients. The temperature dependencies of the loss tangent for both healthy and diabetic nail represent the relation between the electrical energy lost and stored in keratin-glucose-water complexes of this tissue. The differences between these materials concern the temperature ranges in which there appears the decomposition of loosely bound water. The effect of glycation on the loss tangent of the wet and the dry nail is supported by higher values of this parameter than in those describing the healthy samples in the whole temperature range and above 100°C, respectively. In addition, glycation lead to distinct increase in the dielectric relaxation decrement in permittivity and dielectric loss between the frequency of 500 Hz and 100 kHz for the wet and the dry nail. The results of this study indicate that the dielectric spectroscopy may be useful in observing the decomposition of water in the diabetic nail plate.


Assuntos
Diabetes Mellitus Tipo 2/diagnóstico , Glucose/química , Queratinas/química , Unhas/química , Eletricidade , Humanos , Pessoa de Meia-Idade , Unhas/patologia , Água/química
15.
Colloids Surf B Biointerfaces ; 101: 1-5, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-22789782

RESUMO

The temperature and frequency dependencies of the dielectric parameters for the rat artery are used to analyse effects of hypothermia on this tissue. Measurements were performed over the frequency range 500 Hz to 100 kHz and at temperatures from 19 to 60°C. The artery samples contained about 12% water by mass at room temperature at a relative humidity of 70%. The frequency dependencies of the loss tangent for the control, mild hypothermic and moderate hypothermic artery exhibit two peaks at 2 kHz and 35 kHz in the α-dispersion region. The results were discussed in terms of the distribution of relaxation frequencies and the activation energy for the conduction and polarization mechanisms particularly in the elastin-water and collagen-water systems. The knowledge about dielectric behavior of the hypothermic rat artery in vitro is important due to clinical application of local and systemic hypothermia.


Assuntos
Artérias/química , Hipotermia/fisiopatologia , Animais , Colágeno/química , Elastina/química , Condutividade Elétrica , Eletroquímica , Campos Eletromagnéticos , Umidade , Masculino , Ratos , Ratos Wistar , Temperatura
16.
Int J Clin Pharmacol Ther ; 47(8): 533-8, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19640362

RESUMO

OBJECTIVE: This study aimed at evaluating whether supplementation of L-arginine in the course of ischemia and reperfusion syndrome after acute, experimental ischemia of the hind legs of the rat, could influence nitric oxide (NO) concentration and selected biochemical parameters concentration related to the oxidative stress. MATERIAL AND METHODS: The study included 64 male Wistar rats. The animals were divided into four groups: Group I = control, Group II = placebo, Group III = L-arginine (500 mg/kg body mass/day for 5 days, p.o.), Group IV = L-arginine and nonspecific nitric oxide synthase (NOS) inhibitor - N(G)-Nitro-L-arginine-methyl ester (L-NAME) (75 micromol/ rat/day for 5 days, p.o.). Each group was further divided into subgroups: 1 = animals not subjected to ischemia and reperfusion, 2 = animals underwent 4-hour ischemia and subsequent reperfusion. Animals from Subgroup 2 were anesthetized and submitted to acute tourniquet ischemia of the hind limb. Blood samples were collected from all anesthetized rats by puncturing the right ventricle to assess total antioxidant status, lipids' peroxide concentration and nitric oxide concentration before ischemia and at 4th hour of ischemia and at 30th, 60th or 120th minute of reperfusion. RESULTS: We found that administration of L-arginine to rats resulted in significant increase of NO, level of total antioxidant status (TAS), and decrease of lipid' peroxide concentration when compared to the control and placebo groups. All these laboratory changes were progressing along with lengthening of reperfusion time. Simultaneous application of L-NAME led to reversal of phenomena caused by L-arginine. CONCLUSIONS: The present results suggest that L-arginine may protect tissues and organs against ischemia-reperfusion injury. The potential therapeutic role of L-arginine administration in prevention and treatment of ischemia-reperfusion syndrome consequences needs further investigation in humans.


Assuntos
Arginina/farmacologia , Peróxidos Lipídicos/metabolismo , Óxido Nítrico/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Traumatismo por Reperfusão/prevenção & controle , Animais , Arginina/fisiologia , Inibidores Enzimáticos/farmacologia , Membro Posterior/irrigação sanguínea , Peróxidos Lipídicos/sangue , Masculino , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico/sangue , Óxido Nítrico Sintase/antagonistas & inibidores , Ratos , Ratos Wistar , Traumatismo por Reperfusão/metabolismo
17.
Anaesthesist ; 56(3): 212-25, 2007 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-17287995

RESUMO

BACKGROUND: The acute coronary syndrome (ACS) with 16% is one of the most common indication for emergency missions. Care of ACS patients in the Heidelberg emergency service region has been carried out since the beginning of 2005 following an interdisciplinary developed concept based on the current guidelines of the German Society for Cardiology (DGK), the American College of Cardiology (ACC), the American Heart Association (AHA), the European Society of Cardiology (ESC) and the European Resuscitation Council (ERC). MATERIALS AND METHODS: Evaluation of the emergency diagnostic and therapeutic measures for the diagnosis of ACS before and after the introduction of the ACS care concept, was carried out retrospectively for the years 2004 (group 1) and 2005 (group 2) by electronic data processing of the records stored in the emergency medical services documentaion system (NADOK). RESULTS: In the years 2004 before (group 1, n=633) and 2005 after (group 2, n=628) introduction of the ACS care concept, there was a comparable basic diagnostic consisting of a 3-lead electrocardiogram (ECG; 95 versus 97%), manual blood pressure measurement (93 versus 95%) and pulse oxymetry (94 versus 91%) as well as a comparable proportion of patients who received a peripheral vene access (99 versus 100%). There were no significant differences between the two groups. However, after the introduction of the ACS concept, the 12-lead ECG was used significantly more often (49 versus 71%, p=0.0001). Furthermore, a guideline-conform medicinal treatment of ACS patients was used inceasingly more often for anticoagulation with heparin/acetylsalicylic acid (75 versus 84%,p=0.0001) and the use of beta-receptor blockers (32 versus 39%, p=0.009) after introduction of the ACS concept. CONCLUSIONS: The introduction of a regional care concept leads to an optimisation of guideline-conform prehospital treatment for ACS patients.


Assuntos
Doença das Coronárias/terapia , Programas Médicos Regionais , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/uso terapêutico , Pressão Sanguínea , Doença das Coronárias/diagnóstico , Eletrocardiografia , Serviços Médicos de Emergência/normas , Feminino , Alemanha , Guias como Assunto , Humanos , Masculino , Pessoa de Meia-Idade , Oximetria , Transporte de Pacientes
18.
Rocz Akad Med Bialymst ; 50 Suppl 1: 210-2, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16119668

RESUMO

PURPOSE: Aim of the study is to show problems parents have to account for in the process of treatment and their knowledge how to solve them. MATERIAL AND METHODS: Fifty girls and boys aged 5-12 years were participated in this study. The research employed an own questionnaire prepared for this particular purpose. It consisted of three parts: the first part dealt with social-demographic data, the second one with the age of a child at the onset of asthma and accompanying it problems, and finally, the third part was concerned with the knowledge of parents about asthma and its treatment at the time of exacerbation. RESULTS: Out of all children under study, 60% were boys and 40% were girls, 85% of them come from a district town and 15% from rural areas. Almost 42% of parents answered that the most frequent reaction of the peers and particularly children attending the same class to this information was understanding. Only 11% of peers were able to help the children with bronchial asthma in difficult moments. CONCLUSIONS: The study has shown that hay fever and atopic dermatitis accompanying bronchial asthma markedly make their functioning among peers difficult. Bronchial asthma makes most children suffering from it resign from favorite games and plays connected with physical effort. The attitude of peers to these children can be described as indifferent.


Assuntos
Asma/terapia , Grupo Associado , Asma/complicações , Atitude Frente a Saúde , Cuidadores , Criança , Pré-Escolar , Dermatite Atópica/complicações , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Rinite Alérgica Sazonal/complicações
19.
Rocz Akad Med Bialymst ; 50 Suppl 1: 250-3, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16119679

RESUMO

PURPOSE: The aim of the study is to evaluate common knowledge shared by leukemia patients aged 12-18 yrs. and to determine their attitude to the diagnosed disease. MATERIAL AND METHOD: The study group consisted 30 of youth aged 12-18 yrs with diagnosed leukemia, which expressed agreement on participation in investigation. The study employed an own questionnaire entitled: "Common Knowledge of Leukemia among Youth and Their Attitudes to the Diagnosed Disease". RESULTS: Results passed of investigations one surrendered to analysis and one introduced inform of diagrams. Talked over results of investigations summed up are discussion and conclusions. Discussion achieves results of own investigations to these passed by Binnbesela's and of relating current knowledge about new-coined word disease among young people from 12 to 18 year of life, contains also considerations relating situation in which one is found young people with recognized leukemia. CONCLUSIONS: The level of knowledge about leukemia in 12-18-year-old patients is highest in 18-year-old respondents. There is no dependence between the time lapse from the moment of diagnosis and the increase of knowledge on the subject. The attitude of young leukemia patients to their own disease does not change with the time lapse from the moment of diagnosis.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Leucemia/psicologia , Adolescente , Atitude Frente a Saúde , Criança , Feminino , Humanos , Masculino
20.
Peptides ; 26(5): 837-43, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15808914

RESUMO

15 nM/kg b.m. of neurotensin (NT) caused a significant inhibition of LMA within 30 min of administration and this effect persisted up for to the 240 th minute of the experiment. A 15 nM/kgb.m. dose also caused a reduction in SLA which persisted up to the 120 th minute. Sixty minutes after an intraperitoneal administration of NT a decrease in the cholesterol and NEFA levels and an increase in the TG and glycerol levels were observed. These effects were inhibited by the NTR2-blocker (levocabastine) and were not subject to change after an in vivo application of SR 48692.


Assuntos
Metabolismo dos Lipídeos , Mobilização Lipídica/efeitos dos fármacos , Neurotensina/farmacologia , Animais , Lipídeos/sangue , Masculino , Neurotensina/administração & dosagem , Ratos , Ratos Wistar
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