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1.
J Sports Sci Med ; 13(4): 774-81, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25435769

RESUMO

The goal of this study is to evaluate the response of physiological variables to acute normobaric hypoxia compared to normoxia and its influence on the lactate turn point determination according to the three-phase model of energy supply (Phase I: metabolically balanced at muscular level; Phase II: metabolically balanced at systemic level; Phase III: not metabolically balanced) during maximal incremental exercise. Ten physically active (VO2max 3.9 [0.49] l·min(-1)), healthy men (mean age [SD]: 25.3 [4.6] yrs.), participated in the study. All participants performed two maximal cycle ergometric exercise tests under normoxic as well as hypoxic conditions (FiO2 = 14%). Blood lactate concentration, heart rate, gas exchange data, and power output at maximum and the first and the second lactate turn point (LTP1, LTP2), the heart rate turn point (HRTP) and the first and the second ventilatory turn point (VETP1, VETP2) were determined. Since in normobaric hypoxia absolute power output (P) was reduced at all reference points (max: 314 / 274 W; LTP2: 218 / 184 W; LTP1: 110 / 96 W), as well as VO2max (max: 3.90 / 3.23 l·min(-1); LTP2: 2.90 / 2.43 l·min(-1); LTP1: 1.66 / 1.52 l·min(-1)), percentages of Pmax at LTP1, LTP2, HRTP and VETP1, VETP2 were almost identical for hypoxic as well as normoxic conditions. Heart rate was significantly reduced at Pmax in hypoxia (max: 190 / 185 bpm), but no significant differences were found at submaximal control points. Blood lactate concentration was not different at maximum, and all reference points in both conditions. Respiratory exchange ratio (RER) (max: 1.28 / 1.08; LTP2: 1.13 / 0.98) and ventilatory equivalents for O2 (max: 43.4 / 34.0; LTP2: 32.1 / 25.4) and CO2 (max: 34.1 / 31.6; LTP2: 29.1 / 26.1) were significantly higher at some reference points in hypoxia. Significant correlations were found between LTP1 and VETP1 (r = 0.778; p < 0.01), LTP2 and HRTP (r = 0.828; p < 0.01) and VETP2 (r = 0.948; p < 0.01) for power output for both conditions. We conclude that the lactate turn point determination according to the three-phase-model of energy supply is valid in normobaric, normoxic as well as hypoxic conditions. The turn points for La, HR, and VE were reproducible among both conditions, but shifted left to lower workloads. The lactate turn point determination may therefore be used for the prescription of exercise performance in both environments. Key PointsThe lactate turn point concept can be used for performance testing in normoxic and hypoxic conditionsThe better the performance of the athletes the higher is the effect of hypoxiaThe HRTP and LTP2 are strongly correlated that allows a simple performance testing using heart rate measures only.

2.
J Sports Sci Med ; 10(3): 439-44, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-24150615

RESUMO

Platelet-rich plasma (PRP) to increase levels of platelets and growth factors has been used for the treatment of sports injuries suggesting to improve healing and regeneration. This method offers some potential especially for elite athletes. However, the insulin like growth factor-1 (IGF-1) is prohibited by the World Anti Doping Agency and, in addition, there may be a possible link between increased levels of IGF-1 and cancer risk. Aim of the study was to evaluate a systemic increase of IGF-1 after local intramuscular administration of PRP in young healthy moderately trained male subjects. Blood samples were drawn and PRP preparation was performed by means of centrifugation. Enriched plasma was injected into the gluteus muscle. Venous blood was collected and serum prepared before as well as after 0.5, 3 and 24 hours after PRP administration. IGF-1 analysis was performed applying an ELISA test kit. No significant systemic increase of mean IGF-1 was found after the PRP injection. Only one subject showed an increase after 24 h, but all IGF-1 values were found within reference limits. We conclude that a single intramuscular application of PRP does not significantly increase systemic IGF-1 levels. Therefore, a single application of PRP is safe with respect to systemic IGF-1 response and cancer risk and this should be allowed for treatment of muscle injuries in elite athletes. Key pointsThere is no increase of systemic IGF-1 levels after a single local intramuscular administration of PRP.Professional athletes and non-athletes alike can benefit from such a treatment option for muscle injuries and related sports injuries without an increased risk of cancer.More studies are warranted to provide definitive evidence to guide surgeon's decision making regarding the appropriate use for PRP products.

3.
Neurosci Lett ; 442(2): 123-7, 2008 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-18619520

RESUMO

In order to describe how high altitude affects the body during a one night stay at 4000m experiments were performed in a hypobaric chamber and compared to a study on Dachstein (mountain in Austria, 2700m). Ten subjects had to perform a reaction time task at different altitudes. The EEG and ECG were recorded simultaneously. Additionally, the oxygen saturation of the blood was measured at different altitudes and the subjects filled out a Lake Louise questionnaire that describes the degree of altitude mountain sickness (AMS). After elevation from 134m to 4000m in the hypobaric chamber heart-rate increased from 68.9bpm to 81.6bpm, RMSSD (root mean square of squared differences of adjacent heart beat intervals) decreased from 54.3ms to 33.3ms, the LF/HF ratio increased from 2.5 to 3.9 and oxygen saturation decreased to 82.7% after 11h at 4000m altitude. The Lake Louise Score (LSS) reached 3.4 after one night at 4000m. EEG beta activity between 14Hz and 18Hz was attenuated at 4000m and also after return to 134m. The results indicate that the subjects were not able to adapt to 4000m within 12h in the hypobaric chamber. Even after 1h after the return to 134m all parameters are still affected from the night at 4000m altitude. ECG and EEG changes are in line with results obtained at 2700m height at Dachstein.


Assuntos
Altitude , Eletrocardiografia , Oxigênio/sangue , Adaptação Fisiológica/fisiologia , Adulto , Câmaras de Exposição Atmosférica , Eletrocardiografia/métodos , Frequência Cardíaca/fisiologia , Humanos , Masculino , Tempo de Reação/fisiologia , Análise Espectral , Inquéritos e Questionários , Fatores de Tempo
4.
Neurosci Lett ; 377(1): 53-8, 2005 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-15722187

RESUMO

In the Eastern Alps, the Dachstein massif with a height of almost 3000 m is an ideal location for investigating the effects of changes in altitude on the human body. Within a few minutes, a cable car facilitates an ascent from 1702 to 2700 m above sea level, where the partial pressure of oxygen is about 550 mmHg (as compared to 760 mmHg at sea level). In this study, 10 healthy subjects performed a reaction time task at 990 m and 2700 m in altitude. The subjects were instructed to perform a right hand index finger movement as fast as possible after a green light flashed (repeated 50 times). The corresponding electrocardiogram (ECG) and the electroencephalogram (EEG) were recorded. From the ECG heart rate and heart rate variability measures in the time and frequency domain were calculated. An event-related desynchronization/synchronization (ERD/ERS) analysis was performed with the EEG data. Finally, the EEG activity and the ECG parameters were correlated. The study showed that with the fast ascent to 2700 m the heart rate increased and the heart rate variability measures decreased. The correlation analysis indicated a close relationship between the EEG activity and the heart rate and heart rate variability. Furthermore it was shown for the first time that the beta ERS in the 14-18 Hz frequency range (post-movement beta ERS) was significantly reduced at high altitude. Very interesting also is the loss of correlation between EEG activity and cardiovascular measures during finger movement at high altitude. The suppressed post-movement beta ERS at the altitude of 2700 m may be interpreted as results of an increased cortical excitability level when compared with the reference altitude at 990 m above sea level.


Assuntos
Altitude , Eletrocardiografia , Eletroencefalografia , Frequência Cardíaca/fisiologia , Desempenho Psicomotor/fisiologia , Adulto , Eletrocardiografia/métodos , Eletrocardiografia/estatística & dados numéricos , Eletroencefalografia/métodos , Eletroencefalografia/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa/métodos , Tempo de Reação/fisiologia , Fatores de Tempo
5.
Curr Pharm Biotechnol ; 5(1): 89-106, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14965212

RESUMO

So far, chemists, molecular biologists and biochemists have reaped the greatest benefits from mass spectrometry (Aebersold et al., 2003). This type of analysis could, however, be useful in many fields. Mass spectrometry is on its way to the doctor's office (Pusch et al., 2003; Földes-Papp et al., 2002; Henry 1999). The article is focused on laser-activated microprobe mass analysis (LAMMA) and inductively coupled argon plasma mass spectrometry (ICP-MS). Potential applications of the two types of mass spectrometry are demonstrated in clinical medicine. It is the first comprehensive review on qualitative characterization of carbonaceous compounds in lung tissue samples in situ and quantitative trace element determination in body fluids.


Assuntos
Líquidos Corporais/química , Compostos Inorgânicos de Carbono/análise , Espectrometria de Massas/métodos , Oligoelementos/análise , Idoso , Idoso de 80 Anos ou mais , Líquidos Corporais/metabolismo , Compostos Inorgânicos de Carbono/metabolismo , Exposição Ambiental/efeitos adversos , Humanos , Exposição por Inalação/efeitos adversos , Masculino , Espectrometria de Massas de Bombardeamento Rápido de Átomos/métodos , Oligoelementos/metabolismo
6.
Chest ; 121(4): 1111-6, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11948040

RESUMO

BACKGROUND: Eosinophils contain granule proteins such as eosinophil cationic protein (ECP) that have proinflammatory effects on airways. ECP may be released on activation of eosinophils into the plasma and is widely used as a marker of bronchial hyperreactivity and allergic inflammation. Environmental factors as well as intense physical exertion may influence eosinophil-related bronchial hyperreactivity. STUDY OBJECTIVES: To investigate the effect of endurance exercise at moderate altitude on levels of circulating eosinophils, serum ECP, serum osmolality (sOS), and dynamic pulmonary function parameters in healthy mountaineers. SETTING: Alpine field study performed in the Alps of Upper Styria in Austria. Type of exercise: Ascent of a mountain at maximal speed. PARTICIPANTS: Thirty healthy male volunteers from a troop of military mountaineers. RESULTS: Mean ECP concentration increased by 66% at the summit checkpoint (H2) and remained at 63% above baseline (base checkpoint [H0]) after descent (H4), while the blood eosinophil count decreased concomitantly from 250/microL at H0 (preexercise) to 118/microL (53%) at H2 and to 22/microL (81%) at H4. The total serum ECP concentration adjusted to sOS correlated negatively with blood eosinophil count (r = - 0.37; p < 0.0001) and PaO(2) (r = - 0.34; p < 0.001), but positively with the peak expiratory flow (PEF) [r = 0.45; p < 0.0001]. Although sOS correlated with serum ECP at H2 (r = 0.47; p = 0.02) and at 12 h after the start of the experiment (H12) [r = 0.57; p = 0.003], the relationship between total ECP and sOS (r = 0.19; p = 0.034) was less pronounced. FEV(1) in percentage of FVC (%FEV(1)/FVC) [the Tiffenau test], forced expiratory flow rate at 25% of vital capacity, and PEF were significantly higher at H2 than at H0 and H4. %FEV(1)/FVC decreased to 88% (p < 0.01) and 83% (p < 0.001) predicted at H12 and 24 h after start of the experiment, respectively. CONCLUSION: Results provide strong evidence for nonspecific activation of blood eosinophils during prolonged intense aerobic exercise at moderate altitude, modifying both eosinophil dynamics and regulation of ECP release in healthy subjects.


Assuntos
Doença da Altitude/fisiopatologia , Proteínas Sanguíneas/metabolismo , Eosinófilos/fisiologia , Volume Expiratório Forçado/fisiologia , Contagem de Leucócitos , Montanhismo , Resistência Física/fisiologia , Ribonucleases , Capacidade Vital/fisiologia , Adulto , Doença da Altitude/diagnóstico , Hiper-Reatividade Brônquica/diagnóstico , Hiper-Reatividade Brônquica/fisiopatologia , Proteínas Granulares de Eosinófilos , Teste de Esforço , Humanos , Masculino , Pessoa de Meia-Idade , Militares , Fatores de Risco
7.
Exp Biol Med (Maywood) ; 227(5): 291-300, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-11976399

RESUMO

Ultrasensitive detection methods such as laser-induced fluorescence represent the current state-of-the-art in analytics. Single-molecule detection in solution has received a remarkable amount of attention in the last few years because of its applicability to life sciences. Studies have been performed on the fundamentals of the detection processes themselves and on some biological systems. Fluorescence correlation spectroscopy (FCS) is the link for ultrasensitive multicomponent analysis, showing possibilities for experiments on molecular interactions. Based on the theoretical background of FCS, this article gives full explanation of FCS and an update of highlights in experimental biology and medicine studied by FCS. We focus on a repertoire of diverse immunoglobulin specificities, a ribosome display system, single-molecule DNA sequencing, and a mutant enzyme generated by random mutagenesis of amino acids. We describe the usefulness and the enormous potential of the methodology. Further, this contribution clearly indicates that FCS is a valuable tool for solution-phase single-molecule (SPSM) experiments in immunobiology and medicine. In experiments with the Goodpasture autoantibody, we worked out conditions for the design of experiments on a complex single molecule in solution. The possibility to use SPSM-FCS as a quantitation methodology opens up other important applications beyond the scope of this article. Original results extending the published studies are presented for the rational foundation of SPSM-FCS. In this original contribution, we deal with experimental systems for biology and medicine where the number of molecules in solution is very small. This article is mandatory for gaining confidence in the interpretation of experimental SPSM-FCS results on the selfsame, individual single molecule in solution.


Assuntos
Espectrometria de Fluorescência/métodos , Autoanticorpos/análise , Autoanticorpos/sangue , Humanos , Imunoglobulinas/análise , Lasers , Modelos Teóricos , Movimento (Física) , Mutagênese , Ribossomos/química , Sensibilidade e Especificidade , Análise de Sequência de DNA/instrumentação , Análise de Sequência de DNA/métodos , Soluções , Espectrometria de Fluorescência/instrumentação
9.
Biol Trace Elem Res ; 87(1-3): 29-43, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12117231

RESUMO

This study first indicates that the serum trace element Zn tends to decrease in the course of sequential thoracenteses. Other selected essential elements such as copper (Cu), manganese (Mn), molybdenum (Mo), and cobalt (Co) do not reveal loss changes in their serum levels. Therefore, Zn should be monitored in patients who undergo repeated thoracentesis. To measure the magnitude of changes in serum trace elements and the clinical relevance of potential imbalances, concentrations of the essential elements are analyzed in 57 serum/effusion pairs obtained from 5 patients (4 male, 1 female; age 28-78 yr) who underwent repeated thoracenteses as a result of recurrent pleural effusion. All patients declined other therapeutic options such as chemical pleurodesis and/or chest tube placement. The total volumes of fluid removed ranged from 2.3 to 19.3 L and the frequency of thoracentesis ranged from 6 to 15 within a period of 102-174 days. Two patients had benign pleural disease and three had malignancies. Three patients suffered from pleural effusions resulting from exudates (total protein content > 3.0 g/dL, LDH > 200 U/L), and two resulting from transudates (total protein < 3.0 g/dL, LDH < 200 U/L). All trace elements were simultaneously determined by inductively coupled argon plasma-mass spectrometry. In addition, the concentrations of the following clinically relevant parameters were analyzed by standard methods: total protein, pH, leukocyte count, lactate dehydrogenase, and glucose.


Assuntos
Derrame Pleural/metabolismo , Oligoelementos/metabolismo , Zinco/metabolismo , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Controle de Qualidade , Oligoelementos/sangue , Zinco/sangue
10.
Wien Klin Wochenschr ; 114(5-6): 216-21, 2002 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-12238312

RESUMO

Inhalation of dust containing graphite can cause lung disease in foundry workers and workers in graphite mines or mills. Mixed dust pneumoconiosis caused by long-term occupational exposure to graphite dust is a rare disease. Only a few cases of graphite pneumoconiosis have been reported in literature, and these were usually diagnosed post mortem. Our report is of an 80-year-old male patient who had worked in an iron foundry for 20 years and whose work had entailed regular contact with ground graphite and foundry vapors. Chest x-rays revealed both a reticular and nodular pattern in the lung, moderate apical distractions and pleural scarring, all of which were confirmed by high-resolution computed tomography. Bronchoalveolar lavage and transbronchial biopsies were also consistent with mixed dust pneumoconiosis, and due to the long-term dust exposure, graphite pneumoconiosis was strongly suspected. To confirm this diagnosis, the chemical composition of the dark granules in the semi-thin histological sections of the transbronchial biopsies were analyzed using laser microprobe mass spectroscopy. The mass spectra of these black particles were consistent with those of natural graphite powder. Comparative analyses of normal lung tissue did not produce similar spectral patterns. We conclude that histology and cytology does not always suffice to confirm a diagnosis of graphite pneumoconiosis, because black particles are also found in conditions resulting from other exposures, such as heavy smoking or coal mining. Analysis of the composition of particles deposited in the lung tissue offers more precise information, which can be used as evidence in occupational and forensic medicine. Laser microprobe mass spectroscopy can assess the mineral dust load in lung samples.


Assuntos
Poeira , Grafite/efeitos adversos , Exposição Ocupacional/efeitos adversos , Pneumoconiose/diagnóstico , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Idoso , Idoso de 80 Anos ou mais , Biópsia , Broncoscopia , Humanos , Pulmão/patologia , Masculino , Pneumoconiose/patologia , Sensibilidade e Especificidade
11.
Environ Sci Pollut Res Int ; 10(6): 350-3, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14690022

RESUMO

BACKGROUND: Cigarette smoke is a major anthropogenic pollutant and contributes to the permanent load of ambient particulate matter in the air, particularly indoors. It is the leading risk factor for premature loss of life due to chronic bronchitis, emphysema and lung cancer. Smoker's lung and graphite pneumoconiosis are pathological states characterized by the deposition of carbonaceous particles. METHODS: Mass spectrometry was used to evaluate unstained lung sections obtained in vivo from a heavy smoker and a patient with occupationally acquired graphite pneumoconiosis. RESULTS AND DISCUSSION: The composition of carbon compounds deposited in lung tissue samples is demonstrated here for the first time. Thirty carbonaceous-containing microareas from ten biopsies (three areas per biopsy) of lung tissues were analyzed mass-spectrometrically. In each case, the samples were taken from a smoker's lung or those demonstrating a graphite pneumoconiosis. The lung-tissue samples were selected by light microscopy before they were evaporated for mass spectrometry. First-order criteria were anionic and cationic mass peaks which occur within the mass patterns in lung tissues of smoker's lung, although not in graphite pneumoconiosis. Second-order criteria were mass peaks from smoker's lung with standard deviations SD < or = 14% of the mean value. First and second-order mass peaks matched the mass peaks of experimental cigarette-smoke condensate in 9 out of 11 peaks. A software program was developed that enabled fast, automated recognition of the typical mass peaks, and thereby confirmed the histological diagnosis of smoker's lung. CONCLUSIONS: The analysis of carbonaceous particles within lung biopsies from a heavy smoker corresponded to the spectra of tobacco condensate and not to the investigated biopsies of graphite peneumoconiosis. RECOMMENDATION AND OUTLOOK: The analyses were performed in order to find out whether mass-spectrometric criteria exist for the differentiation of carbonaceous lung-tissue deposits. Mass spectrometry may be a valuable tool in determining the composition of carbon compounds deposited in human lung tissue. So far, qualitative assessment of the composition of deposits in lung tissue is only possible after the patient is deceased (autopsy).


Assuntos
Carbono/análise , Exposição por Inalação , Pulmão/química , Exposição Ocupacional , Fumar/efeitos adversos , Poluição por Fumaça de Tabaco/análise , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Espectrometria de Massas/métodos
12.
Artigo em Inglês | MEDLINE | ID: mdl-25378921

RESUMO

Oxidative stress occurs when free radicals and other reactive species overwhelm the availability of antioxidants. Reactive oxygen species (ROS), reactive nitrogen species, and their counterpart antioxidant agents are essential for physiological signaling and host defense, as well as for the evolution and persistence of inflammation. When their normal steady state is disturbed, imbalances between oxidants and antioxidants may provoke pathological reactions causing a range of nonrespiratory and respiratory diseases, particularly chronic obstructive pulmonary disease (COPD). In the respiratory system, ROS may be either exogenous from more or less inhalative gaseous or particulate agents such as air pollutants, cigarette smoke, ambient high-altitude hypoxia, and some occupational dusts, or endogenously generated in the context of defense mechanisms against such infectious pathogens as bacteria, viruses, or fungi. ROS may also damage body tissues depending on the amount and duration of exposure and may further act as triggers for enzymatically generated ROS released from respiratory, immune, and inflammatory cells. This paper focuses on the general relevance of free radicals for the development and progression of both COPD and pulmonary emphysema as well as novel perspectives on therapeutic options. Unfortunately, current treatment options do not suffice to prevent chronic airway inflammation and are not yet able to substantially alter the course of COPD. Effective therapeutic antioxidant measures are urgently needed to control and mitigate local as well as systemic oxygen bursts in COPD and other respiratory diseases. In addition to current therapeutic prospects and aspects of genomic medicine, trending research topics in COPD are presented.


Assuntos
Pulmão/metabolismo , Estresse Oxidativo , Doença Pulmonar Obstrutiva Crônica/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Antioxidantes/uso terapêutico , Biomarcadores/metabolismo , Progressão da Doença , Predisposição Genética para Doença , Humanos , Pulmão/efeitos dos fármacos , Pulmão/fisiopatologia , Estresse Oxidativo/efeitos dos fármacos , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/genética , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Espécies Reativas de Nitrogênio/metabolismo , Fatores de Risco , Fumar/efeitos adversos , Fumar/metabolismo
13.
PLoS One ; 9(9): e106120, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25180783

RESUMO

A recent study showed that ergometry increased circulating hematopoietic stem and progenitor cell (CPC) numbers, but reduced hematopoietic colony forming capacity/functionality under normoxia and normobaric hypoxia. Herein we investigated whether an exercise-induced elevated plasma free/bound norepinephrine (NE) concentration could be responsible for directly influencing CPC functionality. Venous blood was taken from ten healthy male subjects (25.3+/-4.4 yrs) before and 4 times after ergometry under normoxia and normobaric hypoxia (FiO2<0.15). The circulating hematopoietic stem and progenitor cell numbers were correlated with free/bound NE, free/bound epinephrine (EPI), cortisol (Co) and interleukin-6 (IL-6). Additionally, the influence of exercise-induced NE and blood lactate (La) on CPC functionality was analyzed in a randomly selected group of subjects (n = 6) in vitro under normoxia by secondary colony-forming unit granulocyte macrophage assays. Concentrations of free NE, EPI, Co and IL-6 were significantly increased post-exercise under normoxia/hypoxia. Ergometry-induced free NE concentrations found in vivo showed a significant impairment of CPC functionality in vitro under normoxia. Thus, ergometry-induced free NE was thought to trigger CPC mobilization 10 minutes post-exercise, but as previously shown impairs CPC proliferative capacity/functionality at the same time. The obtained results suggest that an ergometry-induced free NE concentration has a direct negative effect on CPC functionality. Cortisol may further influence CPC dynamics and functionality.


Assuntos
Ensaio de Unidades Formadoras de Colônias , Exercício Físico , Células-Tronco Hematopoéticas/citologia , Norepinefrina/sangue , Adulto , Antígenos CD34/metabolismo , Contagem de Células Sanguíneas , Hipóxia Celular , Proliferação de Células , Epinefrina/sangue , Ergometria , Humanos , Hidrocortisona/sangue , Interleucina-6/sangue , Lactatos/sangue , Antígenos Comuns de Leucócito/metabolismo , Masculino
14.
PLoS One ; 9(5): e89005, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24817135

RESUMO

OBJECTIVE: Hypobaric hypoxia, physical and psychosocial stress may influence key cardiovascular parameters including blood pressure (BP) and pulse pressure (PP). We investigated the effects of mild hypobaric hypoxia exposure on BP and PP reactivity to mental and physical stress and to passive elevation by cable car. METHODS: 36 healthy volunteers participated in a defined test procedure consisting of a period of rest 1, mental stress task (KLT-R), period of rest 2, combined mental (KLT-R) and physical task (bicycle ergometry) and a last period of rest both at Graz, Austria (353 m asl) and at the top station Dachstein (2700 m asl). Beat-to-beat heart rate and BP were analysed both during the test procedures at Graz and at Dachstein and during passive 1000 m elevation by cable car (from 1702 m to 2700 m). RESULTS: A significant interaction of kind of stress (mental vs. combined mental and physical) and study location (Graz vs. Dachstein) was found in the systolic BP (p = .007) and PP (p = .002) changes indicating that during the combined mental and physical stress task sBP was significantly higher under hypoxic conditions whereas sBP and PP were similar during mental stress both under normobaric normoxia (Graz) and under hypobaric hypoxia (Dachstein). During the passive ascent in cable car less trivialization (psychological coping strategy) was associated with an increase in PP (p = .004). CONCLUSION: Our data show that combined mental and physical stress causes a significant higher raise in sBP and PP under hypoxic conditions whereas isolated mental stress did not affect sBP and PP under hypoxic conditions. PP-reaction to ascent in healthy subjects is not uniform. BP reactions to ascent that represents an accumulation of physical (mild hypobaric hypoxia) and psychological stressors depend on predetermined psychological traits (stress coping strategies). Thus divergent cardiovascular reactions can be explained by applying the multidimensional aspects of the biopsychosocial concept.


Assuntos
Pressão Sanguínea/fisiologia , Teste de Esforço/métodos , Frequência Cardíaca/fisiologia , Hipóxia/fisiopatologia , Estresse Psicológico/fisiopatologia , Adulto , Fenômenos Fisiológicos Cardiovasculares , Estudos Cross-Over , Feminino , Humanos , Modelos Logísticos , Masculino , Análise Multivariada , Pulso Arterial , Inquéritos e Questionários , Adulto Jovem
15.
Stem Cells Dev ; 21(16): 2915-25, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-22616638

RESUMO

Circulating hematopoietic progenitor cells (CPCs) may be triggered by physical exercise and/or normobaric hypoxia from the bone marrow. The aim of the study was to investigate the influence of physical exercise and normobaric hypoxia on CPC number and functionality in the peripheral blood as well as the involvement of oxidative stress parameters as possibly active agents. Ten healthy male subjects (25.3±4.4 years) underwent a standardized cycle incremental exercise test protocol (40 W+20 W/min) under either normoxic (FiO2 ∼0.21) or hypoxic conditions (FiO2<0.15, equals 3,500 m, 3 h xposure) within a time span of at least 1 week. Blood was drawn from the cubital vein before and 10, 30, 60, and 120 min after exercise. The number of CPCs in the peripheral blood was analyzed by flow cytometry (CD34/CD45-positive cells). The functionality of cells present was addressed by secondary colony-forming unit-granulocyte macrophage (CFU-GM) assays. To determine a possible correlation between the mobilization of CPCs and reactive oxygen species, parameters for oxidative stress such as malondialdehyde (MDA) and myeloperoxidase (MPO) were obtained. Data showed a significant increase of CPC release under normoxic as well as hypoxic conditions after 10 min of recovery (P<0.01). Most interestingly, although CD34+/CD45dim cells increased in number, the proliferative capacity of CPCs decreased significantly 10 min after cessation of exercise (P<0.05). A positive correlation between CPCs and MDA/MPO levels turned out to be significant for both normoxic and hypoxic conditions (P<0.05/P<0.01). Hypoxia did not provoke an additional effect. Although the CPC frequency increased, the functionality of CPCs decreased significantly after exercise, possibly due to the influence of increased oxidative stress levels.


Assuntos
Movimento Celular , Ensaio de Unidades Formadoras de Colônias , Exercício Físico/fisiologia , Hematopoese , Células-Tronco Hematopoéticas/citologia , Adulto , Antígenos CD34/metabolismo , Contagem de Células Sanguíneas , Proliferação de Células , Eritropoetina/metabolismo , Citometria de Fluxo , Humanos , Hipóxia/sangue , Cinética , Antígenos Comuns de Leucócito/metabolismo , Masculino , Malondialdeído/metabolismo , Estresse Oxidativo , Peroxidase/metabolismo
16.
Wien Med Wochenschr ; 158(17-18): 503-8, 2008.
Artigo em Alemão | MEDLINE | ID: mdl-18807241

RESUMO

The behavior of blood pressure under hypoxic conditions depends on individual factors, altitude and duration of stay at altitude. While most humans are normotensive at higher altitudes, a few will react with moderate hypertension or hypotension. Excessive elevation of arterial blood pressure is not even to be expected below 4,000 m. Rather, several weeks' stay at higher altitude will decrease systolic and diastolic blood pressure at rest as well as during physical exertion. A high-altitude treatment for rehabilitation purposes at moderate altitude may be recommended for patients with cardio-circulatory disorders. Improvements can last several months even after returning to accustomed altitudes. Furthermore, endurance-trained hypertensive patients with pharmacologically controlled arterial blood pressure might be able to participate in mountain treks without additional health risk.


Assuntos
Altitude , Pressão Sanguínea/fisiologia , Hipertensão/etiologia , Montanhismo , Anti-Hipertensivos/uso terapêutico , Reabilitação Cardíaca , Diástole/fisiologia , Humanos , Hipertensão/tratamento farmacológico , Hipertensão/fisiopatologia , Hipóxia/etiologia , Hipóxia/fisiopatologia , Resistência Física , Sistema Renina-Angiotensina/fisiologia , Sístole/fisiologia , Fatores de Tempo
17.
Wien Med Wochenschr ; 157(19-20): 490-2, 2007.
Artigo em Alemão | MEDLINE | ID: mdl-18030553

RESUMO

Invasive candidiasis can occur in immunosuppressed patients as well as in critically ill, non-immunocompromised patients and is associated with high mortality (20-40 %). Intestinal Candida colonisation is an important source for invasive candidiasis. Risk factors for the development of invasive candidiasis include presence of an intravascular device, organ dysfunction, impaired mucosal or skin barrier function, therapy with antacids or corticosteroids, prolonged stay at the ICU, total parenteral nutrition and prolonged antibiotic therapy. Among patients with invasive candidiasis, antifungal treatment should be started without delay. Antifungal prophylaxis is currently not recommended in critically ill, non-immunocompromised patients.


Assuntos
Candidíase/diagnóstico , Infecções Oportunistas/diagnóstico , Antifúngicos/uso terapêutico , Candidíase/tratamento farmacológico , Estado Terminal , Infecção Hospitalar/diagnóstico , Infecção Hospitalar/tratamento farmacológico , Fungemia/diagnóstico , Fungemia/tratamento farmacológico , Humanos , Unidades de Terapia Intensiva , Mucosa Intestinal/microbiologia , Neutropenia/diagnóstico , Neutropenia/tratamento farmacológico , Infecções Oportunistas/tratamento farmacológico , Fatores de Risco
18.
J Med Toxicol ; 3(4): 173-7, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18072172

RESUMO

INTRODUCTION: Gasoline, ingested intentionally or accidentally, is toxic. The majority of reported cases of gasoline intoxication involve oral ingestion or inhalation. Data are scarce on complications and outcomes following hydrocarbon poisoning by intravenous injection. CASE REPORT: Following a suicide attempt by intravenous self-injection of 10 ml of gasoline, a 26-year-old medical student was admitted to the intensive care unit (ICU) with hemoptysis, symptoms of acute respiratory failure, chest pain, and severe abdominal cramps. Gas exchange was severely impaired and a chest x-ray indicated chemical pneumonitis. Initial treatment consisted of mechanical ventilation, supportive hyperventilation, administration of nitrogen oxide (NO), and prednisone. Unfortunately, the patient developed multi-organ dysfunction syndrome (MODS) complicated by life-threatening severe vasoplegia within 24 hours after gasoline injection. High doses of vasopressors along with massive amounts of parenteral fluids were necessary. Despite fluid replacement, renal function worsened and required hemofiltration on 5 sequential days. After 12 days of intensive care management, the patient recovered completely and was discharged to a psychiatric care facility. DISCUSSION: Intravenous gasoline injection causes major injury to the lungs, the organ bearing the first capillary bed encountered. Treatment of gasoline poisoning is symptomatic because no specific antidote is available. Early and aggressive supportive care may be conducive to a favorable outcome with minimal residual pulmonary sequelae.


Assuntos
Gasolina/intoxicação , Pneumonia/induzido quimicamente , Intoxicação/etiologia , Tentativa de Suicídio , Adulto , Dióxido de Carbono/sangue , Humanos , Injeções Intravenosas , Masculino , Oxigênio/sangue , Pressão Parcial , Pneumonia/terapia , Intoxicação/terapia , Radiografia Torácica , Tomografia Computadorizada por Raios X , Resultado do Tratamento
19.
Wien Med Wochenschr ; 157(19-20): 466-72, 2007.
Artigo em Alemão | MEDLINE | ID: mdl-18030549

RESUMO

Pulmonary mycetomas, or fungus balls, consist of spherical masses of mycelia and hyphae, fibrin and granulocytes that grow and partly fill cavitary lesions without invading tissue. They are usually caused by molds of the Aspergillus species, rarely by Mucor or yeast fungi such as Candida species, that colonize damaged lung tissue. Hemoptysis is the most frequent symptom. Since systemic and local administration of antifungal agents is of uncertain efficacy, resectional surgery should be the treatment of choice in cases of severe hemoptysis, if lung function is not severely compromised. As pulmonary resection in the form of lobectomy or pneumonectomy is associated with raised mortality, cavernostomy and cavernoplasty may be options for high-risk patients.


Assuntos
Hemoptise/etiologia , Pneumopatias Fúngicas/diagnóstico , Micetoma/diagnóstico , Aspergillus , Candida , Diagnóstico Diferencial , Hemoptise/microbiologia , Hemoptise/cirurgia , Humanos , Pneumopatias Fúngicas/microbiologia , Pneumopatias Fúngicas/cirurgia , Mucor , Micetoma/microbiologia , Micetoma/cirurgia , Pneumonectomia , Tomografia Computadorizada por Raios X
20.
Wien Med Wochenschr ; 155(7-8): 193-8, 2005 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-15966266

RESUMO

Laboratory ergometry to exhaustion allows cardiopulmonal risk assessment for the prevention of health problems related to mountaineering. Moreover, exercise testing evaluates functional status, so permitting individualized training programs and evaluation of training effects. Additionally, mountaineering-specific performance diagnosis allows individual as well as group-specific determination of exercise performance related to field conditions. Laboratory tests are standardized, easy to perform and cost effective. Treadmill ergometry with constant walking speed and increasing inclination is suggested to be predictive for mountaineering performance. On the other hand, the validity for the specific conditions for mountaineering is questionable. Standardized laboratory exercise tests combined with sport-specific exercise tests provide rough information on the ability to sustain real-situation strain. To compare individual exercise performance, published data tables obtained from field tests may be used. It must, however, be mentioned that high-altitude-adaptation is independent of exercise performance evaluated separately.


Assuntos
Doença da Altitude/fisiopatologia , Teste de Esforço/métodos , Montanhismo/fisiologia , Aptidão Física/fisiologia , Aclimatação/fisiologia , Doença da Altitude/prevenção & controle , Humanos , Resistência Física/fisiologia , Medição de Risco
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