RESUMO
Transitional cell carcinoma of the bladder can - in the majority of cases - be safely treated by transurethral resection and bladder preservation. In case of more aggressive and genetically instable tumors, the effect of radical cystectomy depends on tumor volume. If complete resection of invasive tumors is also possible, the additional effect of radical cystectomy seems to be marginal. In patients with favorable tumor location and acceptable prostate parameters, prostate-sparing surgery seems to be oncologically safe with good quality of life.
Assuntos
Carcinoma de Células de Transição/cirurgia , Cistectomia/métodos , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Tratamentos com Preservação do Órgão/métodos , Órgãos em Risco/cirurgia , Neoplasias da Bexiga Urinária/cirurgia , Carcinoma de Células de Transição/diagnóstico , Humanos , Recuperação de Função Fisiológica , Neoplasias da Bexiga Urinária/diagnósticoRESUMO
BACKGROUND: Local cold therapy for burns is generally recommended to relief pain and limit tissue damage, however, there is limited data of its physiological benefit. This study aimed to evaluate pathophysiological effects of cold therapy in superficial burn on microcirculation, edema formation, and histomorphology. METHODS: In 12 volunteers (8f, 4m; aged 30.4±14.1 years) circumscribed superficial burn was induced on both hand back and either left untreated as control (control-group) or treated by local-cold-application (cold-treatment-group). Prior to burn (t0), immediately (t1), 15 min (t2), and 30 min (t3) following cold therapy, following parameter was evaluated using intravital-microscopy; epidermal-thickness (ET), granular-cell-size (GCS), individual-blood-cell-flow (IBCF), and functional-capillary-density (FCD). RESULTS: Both ET and GCS increased significantly more in control-group and slightly in cold-treatment-group in t1, while turns to insignificant t2 onwards. IBCF and FCD raised up in control-group compared to dramatically decrease in cold-treatment-group in t1. In t2 both parameter remains in control-group and increased in cold-treatment-group. Comparison of both groups for IBCF and FCD indicates significant difference in t1 and t2, however, insignificant in t0 and t3. CONCLUSIONS: Microcirculation, edema formation, and histomorphology of superficial burn has been significantly influenced through immediate cold therapy, however, this alterations are transient and turns to ineffective after 30 min.
Assuntos
Queimaduras/terapia , Crioterapia/métodos , Edema/prevenção & controle , Traumatismos da Mão/terapia , Microcirculação , Manejo da Dor/métodos , Pele/lesões , Adolescente , Adulto , Queimaduras/complicações , Queimaduras/patologia , Capilares/patologia , Edema/etiologia , Epiderme/patologia , Feminino , Traumatismos da Mão/patologia , Humanos , Masculino , Microscopia Confocal , Pessoa de Meia-Idade , Dor/etiologia , Fluxo Sanguíneo Regional , Pele/irrigação sanguínea , Pele/patologia , Adulto JovemRESUMO
Irisin, a newly discovered, PGC-1α dependent myokine, has recently been shown to increase in circulation in response to sprint exercise. This study examined the effect of prolonged exercise on irisin concentrations in young men (n=7) as well as in young women (n=5) during different stages of the menstrual cycle. Seven young men completed 90 min of treadmill exercise at 60% of VO2max and a resting control trial. Five women completed the same exercise protocol in two different trials: during the early follicular phase and mid-luteal phase of the menstrual cycle. Blood samples were collected and analyzed for irisin concentrations immediately before exercise, at 54 and 90 min of exercise, and at 20 min of recovery (R20). Findings revealed that by 54 min of a 90 min treadmill exercise protocol at 60% of VO2max, irisin concentrations significantly increased 20.4% in young men and 20.3% as well as 24.6% in young women during the early follicular and mid-luteal phases of the menstrual cycle, respectively. However, by 90 min of exercise as well as R20, irisin concentrations were no longer elevated. Stage of the menstrual cycle did not affect responses in young women. Findings indicate that prolonged aerobic exercise produces a transient increase in irisin concentrations during the first hour of exercise for both genders and suggest that this form of moderate exercise may be helpful in improving fat metabolism.
Assuntos
Exercício Físico/fisiologia , Fibronectinas/sangue , Adulto , Índice de Massa Corporal , Feminino , Fase Folicular/sangue , Humanos , Cinética , Fase Luteal/sangue , Masculino , Consumo de Oxigênio , Fatores de Tempo , Adulto JovemRESUMO
INTRODUCTION: Salvage rates of free flaps have been reported to be inversely related to the time interval between the onset of ischaemia and its clinical recognition. Consecutively, monitoring of free flaps remains of major importance. The aim of this study was to analyse the correlation of postoperative free flap microcirculation and free flap skin temperature as a potential tool of postoperative flap monitoring. HYPOTHESIS: Free flap skin temperature correlates to free flap capillary microcirculation. METHODS: Fifty-four free flaps were prospectively monitored during the study. Postoperative flap monitoring was performed using a regular digital infrared surface thermometer (Medisana FTD, Germany) simultaneously to microcirculatory assessment using combined Laser-Doppler and photospectrometry (Oxygen-to-see, Lea Medizintechnik, Germany). RESULTS: Mean microcirculatory blood flow was 105±35 arbitrary units (AU). Mean temperature was 34.9±2.2 °C. We found a significant correlation between free flap temperature and free flap capillary blood flow (Pearson correlation r=0.48; p<0.001) and postcapillary venous filling pressure (r=-0.32; p=0.021) in 54 free flaps. A 1 °C less free flap temperature was associated with a decrease of the mean microcirculatory capillary blood flow by 37 relative units. CONCLUSION: Our study demonstrates free flap skin temperature related to capillary microcirculation. Our primary hypothesis was confirmed. We postulate an acute temperature drop of 3 °C at the centre of the skin island as indicative of arterial thrombosis, whereas a 1-2 °C uniform temperature drop of the flap is indicative of venous compromise. Consecutively, free flap skin temperature assessment might be a reliable and inexpensive adjunct monitoring method in plastic reconstructive surgery to improve patients' safety.
Assuntos
Fluxometria por Laser-Doppler , Microcirculação , Retalhos Cirúrgicos/irrigação sanguínea , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica , Temperatura CutâneaRESUMO
No studies have examined the time-course changes of the appetite stimulating hormone, agouti-related peptide (AgRP), induced by exercise training. The purpose of the study was to determine the effects of short (3 weeks), moderate (9 weeks), and long-term (12 weeks) treadmill training on plasma and soleus concentrations of AgRP, as well as ATP and glycogen concentrations in soleus muscle and liver tissues. 54 Wistar male rats were randomly assigned into control (total n=27; 3 week control=10; 9 week control=8; 12 week control=9) and training (total n=27; 3 week trained=10; 9 week trained=8; 12 week trained=9). The training groups ran for 60 min/d, 5 d/wk at 25 m/min and 0% grade for 3, 9, and 12 weeks. After the last exercise session soleus muscle, liver, and plasma were collected and frozen. Results demonstrated that after 3, 9, and 12 weeks of exercise training there was an increase in plasma and soleus AgRP that declined with age. Soleus muscle glycogen was inversely related to AgRP. After 9 weeks of training there was a significant decrease and increase in plasma insulin and cortisol, respectively. Thus, as little as 3 weeks of running enhances AgRP concentration in rat soleus and plasma whereas changes in liver ATP and glycogen and soleus muscle glycogen require 9 weeks for alteration. Plasma and soleus muscle AgRP decline with age, and AgRP concentration in plasma and soleus are related to insulin, soleus ATP, and liver glycogen.
Assuntos
Trifosfato de Adenosina/metabolismo , Proteína Relacionada com Agouti/metabolismo , Glicogênio/metabolismo , Hidrocortisona/sangue , Insulina/sangue , Músculo Esquelético/metabolismo , Fragmentos de Peptídeos/metabolismo , Trifosfato de Adenosina/sangue , Proteína Relacionada com Agouti/sangue , Animais , Teste de Esforço , Glicogênio/sangue , Fígado/metabolismo , Masculino , Fragmentos de Peptídeos/sangue , Condicionamento Físico Animal , Ratos , Ratos Wistar , Fatores de TempoRESUMO
BACKGROUND: It has been suggested that circulating ghrelin levels are upregulated by fasting, hypoglycemic status, and a physical exercise-induced energy deficit. AIM: The purpose of the present study was to investigate the timecourse adaptations of the plasma, fundus, and small intestine ghrelin concentrations as well as related hormones and liver ATP levels to 3, 6, and 12 weeks of treadmill endurance running. MATERIAL/SUBJECTS AND METHODS: Thirty-nine male Wistar rats (12-14 weeks old) were randomly assigned to 3 control (C3, no.=5; C6, no.=7 and C12, no.=7) and 3 training groups (E3, no.=6; E6, no.=7 and E12, no.=7). The rats in the 3 training groups were exercised on a motor-driven treadmill at 25 m/min (0% grade) for 60 min/day, 5 days/week for 3, 6, and 12 weeks, respectively. The animals were sacrificed 48 h after the last session of each training program and tissues were analyzed. RESULTS: Total ghrelin concentrations were significantly (p<0.05) lower in trained rat plasma and fundus tissue after all treadmill endurance running programs. Small intestine ghrelin concentrations remained unchanged. Plasma GH concentrations and liver ATP content were significantly higher in E6 and E12 groups. CONCLUSION: Data indicate that as little as 3 weeks of moderate treadmill exercise reduces plasma and fundus total ghrelin concentrations with elevated plasma GH and liver ATP content occurring after 6 and 12 weeks of training. Exercise training-induced improvement of energy source availability and negative feedback from increased GH levels may play a role in reducing plasma and fundus ghrelin levels.
Assuntos
Teste de Esforço/métodos , Fundo Gástrico/metabolismo , Grelina/metabolismo , Intestino Delgado/metabolismo , Condicionamento Físico Animal , Plasma/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Insulina/metabolismo , Fígado/metabolismo , Masculino , Ratos , Ratos WistarRESUMO
Blood platelets provide the initial response to vascular endothelial injury, becoming activated as they adhere to the injured site. Activated platelets recruit leukocytes, and initiate proliferation and migration of vascular smooth muscle cells (SMC) within the injured vessel wall, leading to development of neointimal hyperplasia. Endothelial CD39/NTPDase1 and recombinant solCD39 rapidly metabolise nucleotides, including stimulatory ADP released from activated platelets, thereby suppressing additional platelet reactivity. Using a murine model of vascular endothelial injury, we investigated whether circulating human solCD39 could reduce platelet activation and accumulation, thus abating leukocyte infiltration and neointimal formation following vascular damage. Intraperitoneally-administered solCD39 ADPase activity in plasma peaked 1 hour (h) post-injection, with an elimination half-life of 43 h. Accordingly, mice were administered solCD39 or saline 1 h prior to vessel injury, then either sacrificed 24 h post-injury or treated with solCD39 or saline (three times weekly) for an additional 18 days. Twenty-four hours post-injury, solCD39-treated mice displayed a reduction in platelet activation and recruitment, P-selectin expression, and leukocyte accumulation in the arterial lumen. Furthermore, repeated administration of solCD39 modulated the late stage of vascular injury by suppressing leukocyte deposition, macrophage infiltration and smooth muscle cell (SMC) proliferation/migration, resulting in abrogation of neointimal thickening. In contrast, injured femoral arteries of saline-injected mice exhibited massive platelet thrombus formation, marked P-selectin expression, and leukocyte infiltration. Pronounced neointimal growth with macrophage and SMC accretion was also observed (intimal-to-medial area ratio 1.56 +/- 0.34 at 19 days). Thus, systemic administration of solCD39 profoundly affects injury-induced cellular responses, minimising platelet deposition and leukocyte recruitment, and suppressing neointimal hyperplasia.
Assuntos
Antígenos CD/uso terapêutico , Apirase/uso terapêutico , Hiperplasia/prevenção & controle , Túnica Íntima/patologia , Animais , Antígenos CD/farmacologia , Apirase/farmacologia , Movimento Celular/efeitos dos fármacos , Quimiotaxia de Leucócito/efeitos dos fármacos , Endotélio Vascular/patologia , Humanos , Hiperplasia/tratamento farmacológico , Hiperplasia/patologia , Macrófagos , Camundongos , Miócitos de Músculo Liso , Ativação Plaquetária/efeitos dos fármacos , Solubilidade , Trombose/prevenção & controleRESUMO
HYPOTHESIS: We hypothesized that pool swimming has a low risk for acute injuries; however overuse injuries are predominant, depending on exposure time and swimming discipline. METHODS: 341 elite swimmers (19 +/- 11 years, BMI 20.3 +/- 3) were enrolled. Swimming was performed at mean since 10.1 +/- 8 years with 3.8 units every week during 43 weeks every year. RESULTS: The overall pool swimming injury rate was 0.39 / 1000 h. Overuse injuries (0.22 / 1000 h) were more frequent than acute injuries (0.17 / 1000 h). The upper extremity was involved more frequently (0.11 / 1000 h) than the trunk (0.067 / 1000 h) or the lower extremity (0.085 / 1000 h). Knee pain was predominant (0.17 / 1000 h) followed by shoulder overuse injuries (0.11 / 1000 h). Especially the 200 - 400 m breaststroke event had a fivefold higher risk for knee pain (relative risk, RR 5.1, p = 0.001). Freestyle had a reduced relative risk for knee pain (RR 0.5, p = 0.03), where shoulder overuse syndromes were predominant. Butterfly increased acute shoulder injury with RR 4.4 (p = 0.004), cervical spine injuries (RR 4.0, p = 0.03) and lower back pain (RR 2.5, p = 0.011). Swimming for more than four times a week had a higher risk for knee injuries (RR 2.1) and shoulder injuries (RR 4.0). We found that stretching was associated with a fivefold reduced risk for overuse knee injuries. CONCLUSION: Competitive swimming is a reasonable safe sport, where overuse injuries are predominant. 200 - 400 m breaststroke events increase the risk for knee overuse injuries more than other disciplines. Training for more than four times a week increases the risk twofold for knee and fourfold for shoulder overuse injuries.
Assuntos
Traumatismos do Joelho/etiologia , Natação/lesões , Adolescente , Adulto , Distribuição de Qui-Quadrado , Interpretação Estatística de Dados , Feminino , Humanos , Masculino , Educação Física e Treinamento , Propriocepção/fisiologia , Risco , Fatores de Risco , Fatores Sexuais , Lesões do Ombro , Natação/fisiologia , Fatores de TempoRESUMO
Seven weight-trained males performed both light resistance with partial occlusion (LRO: 30% 1 RM) and moderate resistance (MR: 70% 1 RM) to failure to ascertain whether blood protein carbonyls (PC) and glutathione status was altered compared to partial occlusion (PO) in a counterbalanced fashion. PO was identical in duration to the LRO session and all sessions were on separate days. PC did not differ for the three conditions at PRE (0.05 nM mg protein(-1)). PC significantly increased for PO and MR over time and was greater than the LRO treatment at POST (0.13 nM mg protein(-1)). The GSSG/TGSH ratio at PRE did not differ across treatments (8%) whereas the ratio at POST was significantly elevated for PO and MR treatments (17%). In contrast, no change occurred for the LRO session at any time. These results indicate that MR to failure and PO can significantly increase blood oxidative stress but LRO did not elicit oxidative stress.
Assuntos
Glutationa/sangue , Isquemia/metabolismo , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/metabolismo , Estresse Oxidativo , Carbonilação Proteica , Treinamento Resistido , Grau de Desobstrução Vascular , Adolescente , Adulto , Braço , Dissulfeto de Glutationa/sangue , Hormônio do Crescimento Humano/sangue , Humanos , Isquemia/fisiopatologia , Masculino , Volume Plasmático , Fatores de Tempo , Adulto JovemRESUMO
BACKGROUND: Assessment of lung volume (FRC) and ventilation inhomogeneities with ultrasonic flowmeter and multiple breath washout (MBW) has been used to provide important information about lung disease in infants. Sub-optimal adjustment of the mainstream molar mass (MM) signal for temperature and external deadspace may lead to analysis errors in infants with critically small tidal volume changes during breathing. METHODS: We measured expiratory temperature in human infants at 5 weeks of age and examined the influence of temperature and deadspace changes on FRC results with computer simulation modeling. A new analysis method with optimized temperature and deadspace settings was then derived, tested for robustness to analysis errors and compared with the previously used analysis methods. RESULTS: Temperature in the facemask was higher and variations of deadspace volumes larger than previously assumed. Both showed considerable impact upon FRC and LCI results with high variability when obtained with the previously used analysis model. Using the measured temperature we optimized model parameters and tested a newly derived analysis method, which was found to be more robust to variations in deadspace. Comparison between both analysis methods showed systematic differences and a wide scatter. CONCLUSION: Corrected deadspace and more realistic temperature assumptions improved the stability of the analysis of MM measurements obtained by ultrasonic flowmeter in infants. This new analysis method using the only currently available commercial ultrasonic flowmeter in infants may help to improve stability of the analysis and further facilitate assessment of lung volume and ventilation inhomogeneities in infants.
Assuntos
Fluxômetros , Capacidade Residual Funcional/fisiologia , Ultrassonografia/métodos , Simulação por Computador , Feminino , Fluxômetros/normas , Humanos , Lactente , Recém-Nascido , Masculino , Modelos Biológicos , Espaço Morto Respiratório , TemperaturaRESUMO
The aim of the study was to assess the combination of compression and cryotherapy (Cryo/Cuff ankle device) on parameters of ankle microcirculation in healthy volunteers over 30 min. In 21 volunteers (12 males, 29 +/- 10 years [incl. females], BMI 24 +/- 3) the Cryo/Cuff ankle device (AIRCAST, Summit, NJ, USA) was applied with continuous assessment of parameters of ankle microcirculation, such as tissue oxygen saturation (SO2), relative postcapillary venous filling pressures (rHb), and microcirculatory blood flow at 2- and 8-mm tissue depths during 30 min with the Oxygen-to-see System, a laser-Doppler-spectrophotometry-system (LEA Medizintechnik, Giessen, Germany). Superficial tissue oxygen saturation (SO2, 48 +/- 19 %) immediately dropped to 23 +/- 15 % (-52 %, p < 0.05) within the first 2 min after Cryo/Cuff activation with a consecutive slow decrease to 32 +/- 23 % (- 32 %, p < 0.05 vs. baseline) after 30 min. Deep SO2 (8 mm, 69 +/- 5 %) did not change within 30 min of Cryo/Cuff application (70 +/- 4 %, n.s.). Superficial postcapillary venous filling pressures (61 +/- 17 relative units) showed an immediate and sustained decrease after Cryo/Cuff application within four minutes to 37 +/- 18 relative units (-39 %, p < 0.05). Deep postcapillary venous filling pressures (85 +/- 20 relative units) dropped within the first four minutes of Cryo/Cuff application to 68 +/- 19 relative units (-20 %, p < 0.05). Superficial microcirculatory blood flow (21 +/- 36 relative units) decreased significantly to 7 +/- 5 relative units after 30 min (-69 %, p < 0.05 vs. baseline). Deep microcirculatory blood flow at 8 mm tissue depth (63 +/- 43 relative units) significantly decreased over the 30 min to 39 +/- 23 relative units (-47 %, p < 0.05 vs. baseline). Using the Oxygen-to-see system we could demonstrate significant effects of the Cryo/Cuff device on the ankle level in healthy volunteers with reduced superficial tissue oxygen saturation with preserved deep tissue oxygen saturation, reduced superficial and deep postcapillary venous filling pressures, and reduced superficial and deep microcirculatory blood flow as a function of time. Further clinical studies are mandatory to elucidate the effects of the Cryo/Cuff device on the microcirculatory environment in injured ankles.
Assuntos
Tornozelo/irrigação sanguínea , Crioterapia/instrumentação , Adulto , Velocidade do Fluxo Sanguíneo , Distribuição de Qui-Quadrado , Feminino , Humanos , Fluxometria por Laser-Doppler , Masculino , Microcirculação , Oxigênio/sangue , Pressão , Estudos Prospectivos , Espectrofotometria , EsportesRESUMO
OBJECTIVE: Heavy resistance exercise increases growth hormone (GH) and blood glucose levels. Ghrelin is an endogenous ligand for the GH secretagory receptor that stimulates growth hormone release. Circulating ghrelin levels are suppressed by insulin and glucose. The study was conducted to determine effects of concentric (CON) and eccentric (ECC) muscle actions at the same absolute workload on circulating ghrelin and glucose as well as related glucoregulatory peptides. METHODS: Ten-RM loads for bench press, leg extension, military press, and leg curl were obtained from nine males, mean age 25. +/- 1.2 yr and body fat 17.2 +/- 1.6%. Subjects then completed two experimental trials of either CON or ECC contractions at the same absolute workload. Subjects performed four sets of 12 repetitions for each exercise at 80% of a 10-RM with 90 s rest periods. A pulley system or steel levers were positioned on each machine to raise or lower the weight so only CON or ECC contractions were performed. Pre-, post-, and 15-min post-exercise blood samples were collected. RESULTS: Ghrelin did not increase in response to either muscle action and actually declined during the CON trial. Glucose and insulin increased regardless of the form of muscle action, but amylin and C-peptide did not change. CONCLUSIONS: Data indicate that ghrelin does not contribute to moderate resistance exercise-induced increases in growth hormone, whether from CON or ECC muscle actions. Results suggest that with a moderate loading protocol both CON and ECC muscle actions performed at the same absolute workload elevate glucose and insulin concentrations, but are not related to post-CON exercise ghrelin suppression.
Assuntos
Glucose/metabolismo , Hormônio do Crescimento/metabolismo , Contração Muscular/fisiologia , Músculo Esquelético/fisiologia , Hormônios Peptídicos/metabolismo , Adulto , Amiloide/sangue , Peptídeo C/sangue , Exercício Físico/fisiologia , Grelina , Humanos , Insulina/metabolismo , Polipeptídeo Amiloide das Ilhotas Pancreáticas , MasculinoRESUMO
It has been suggested that ghrelin may play a role in growth hormone (GH) responses to exercise. The present study was designed to determine whether ghrelin, GH, insulin-like growth factor-I (IGF-I), and IGF-binding protein-3 (IGFBP-3) were altered by a progressively intense running protocol. Six well-trained male volunteers completed a progressively intense intermittent exercise trial on a treadmill that included four exercise intensities: 60%, 75%, 90%, and 100% of Vo2max. Blood samples were collected before exercise, after each exercise intensity, and at 15 and 30 mins following the exercise protocol. Subjects also completed a separate control trial at the same time of day that excluded exercise. GH changed significantly over time, and GH area under the curve (AUC) was significantly higher in the exercise trial than the control trial. Area under the curve IGF-I levels for the exercise trial were significantly higher than the control trial. There was no difference in the ghrelin and IGFBP-3 responses to the exercise and control trials. Pearson correlation coefficients revealed significant relationships between ghrelin and both IGF-I and IGFBP-3; however, no relationship between ghrelin and GH was found. In conclusion, intense running produces increases in total IGF-I concentrations, which differs from findings in previous studies using less rigorous running protocols and less frequent blood sampling regimens. Moreover, running exercise that produces substantial increases in GH does not affect peripheral ghrelin levels; however, significant relationships between ghrelin and both IGF-I and IGFBP-3 exist during intense intermittent running and recovery, which warrants further investigation.
Assuntos
Hormônio do Crescimento/sangue , Fator de Crescimento Insulin-Like I/fisiologia , Hormônios Peptídicos/sangue , Corrida/fisiologia , Adolescente , Adulto , Área Sob a Curva , Grelina , Humanos , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , MasculinoRESUMO
AIM: Running at incremental velocities proximal to the onset of blood lactate accumulation (OBLA) elicits linear increases in VO(2), and HR, while the increases in V(E) and blood lactic acid concentrations (BLa) are curvilinear. In addition, effort sense is often measured in the field with the traditional 15-point scale Ratings of Perceived Exertion scale, increases linearly whereas the perceptual response of affect seem to decrease in a nonlinear manner. This study examined the changes in effort sense (RPE) and affect, utilizing the Feeling Scale (FS), at 3 running intensities proximal to the onset of blood lactate accumulation. In addition, the relationship between these perceptual responses and V(E), VO(2), HR, RER, and BLa were examined. METHODS: Eleven highly-trained distance runners (VO(2max) = 67.65+/-1.24) participated in 2 sessions of data collection. During Session 1 subjects performed a discontinuous progressive treadmill protocol to determine peak aerobic power. After each stage a finger tip blood sample was taken to determine BLa. A regression line between the 2 successive workloads that produced BLa above and below 4 mM was calculated to predict the VO(2) that would generate 4mM BLa (VO(2) @ 4 mM). Within 1 week each subject returned for Session 2, which included a 10-min warm-up run followed by 3 submaximal runs lasting 5 min each: the VO(2) at 10% below OBLA (VO(2) 10% ), the VO(2) at OBLA (VO(2) @ 4 mM), and the VO(2) at 10% above OBLA (VO(2) 10%). During the last minute of each run VO(2), V(E), HR, RER, RPE, and FS were assessed. In addition, Bla was assessed immediately following each run. RESULTS: Results demonstrated that VO(2) 10%, VO(2) @ 4 mM, and VO(2) 10% - elicited BLa of 2.66+/-0.33, 3.75+/-0.40, and 6.10+/-0.68 mM, respectively. In addition, RPE increased significantly from VO(2) 10% to VO(2) @ 4 mM and from VO(2) @ 4 mM to VO(2) 10% -; whereas FS demonstrated a slight decrease from VO(2) 10% to VO(2) @ 4 mM, and a more substantial and significant decrease from VO(2) @ 4 mM to VO(2) 10% -. Correlational analyses revealed significant relationships at VO(2) 10% -. Specifically, RPE and FS were negatively related (r=0.62), while RPE and VO(2) were positively related (r=0.53). Correlations across all workloads revealed a tendency for more powerful relationships to exist among RPE and physiological cues than FS and physiological cues. CONCLUSION: This is the first study to directly examine changes in RPE and FS in relation to the physiological threshold for anaerobic metabolism, Bla, which responds to linear increases in exercise intensity in a curvilinear manner. Results support previous investigations suggesting a that the drop in FS has some distinction from the increase in RPE and that FS may be more sensitive to the onset of anaerobic metabolism. Moreover, the relationship of RPE to FS at VO(2) 10% -, but not VO(2) 10% and VO(2) @ 4 mM, supports the hypothesis that the unique variability of FS is diminished at higher intensities of exercise when physiological cues are unambiguous.
Assuntos
Afeto/fisiologia , Ácido Láctico/sangue , Percepção/fisiologia , Corrida/fisiologia , Adulto , Análise de Variância , Exercício Físico/fisiologia , Humanos , Regressão Psicológica , Fatores de TempoRESUMO
AIM: The purpose of this study was to examine changes in selected kinematic variables at 3 running intensities proximal to the onset of blood lactate accumulation (OBLA; 4 mM of blood lactate). It was hypothesized that greater changes in lower body mechanics would occur when running faster than normal race pace compared to when running slower than race pace. METHODS: Nine competitive male distance runners ran at 3 running intensities (RI): 1) each runner's VO(2) at 10% below the VO(2) at OBLA, 2) VO(2) at OBLA, and 3) VO(2) at 10% above the VO(2) at OBLA. Selected kinematic and physiological variables were measured at each RI. RESULTS: VO(2) at RI 1, 2 and 3 was highly correlated with running speed (r=0.93). The blood lactate (BL) showed a nonlinear increase from RI 1 (2.9+/-0.8 mM) to 2 (4.1+/-0.9 mM) to 3 (6.7+/-1.8 mM). The vertical oscillation of center of gravity (VOCOG), stride frequency (SF), range of motion (ROM) of trunk angle, and maximal knee flexion during flight phase (MKFF) changed nonlinearly as did the BL. Significant relationships between BL and VOCOG (r=0.44) and between BL and SF (r=0.51) were found (ps<0.05). CONCLUSION: The findings show a possibility that lower body running mechanics have a relationship with BL.
Assuntos
Marcha/fisiologia , Ácido Láctico/sangue , Corrida/fisiologia , Adulto , Análise de Variância , Fenômenos Biomecânicos , Exercício Físico/fisiologia , Humanos , Masculino , Amplitude de Movimento Articular/fisiologia , Fatores de TempoRESUMO
Amylin, a peptide hormone released from the beta cells of the pancreas and cosecreted with insulin, is reported to inhibit the release of postprandial glucagon and insulin and to modulate gastric emptying. Changes in insulin and glucagon are important for controlling blood glucose levels under conditions in which metabolic rate is elevated, such as during and following exercise. Amylin may participate in the regulation of blood glucose levels in response to exercise, although the role of amylin has not been investigated. The purpose of the study was to determine the effects of a progressive, intermittent exercise protocol on amylin concentrations and to compare its response to circulating levels of insulin, glucagon, cortisol, and glucose. Seven well-trained males completed an intermittent exercise trial on a treadmill at four progressive exercise intensities: 60%, 75%, 90%, and 100% of maximum oxygen consumption (.VO(2)max). Blood samples were collected before exercise, after each exercise intensity, and for 1 hour following the exercise protocol. Subjects also completed a control trial with no exercise. Amylin and insulin rose from baseline (5.79 +/-.78 pmol/L and 4.76 +/-.88 microIU/mL) to peak after 100% .VO(2)max (9.16 +/- 1.35 pmol/L and 14.37 +/- microIU/ml), respectively and remained elevated during much of recovery. Thus, a progressive intermittent exercise protocol of moderate to maximum exercise intensities stimulates increases in amylin levels in well-trained individuals in a similar fashion to that of insulin, whereas glucagon concentrations only increase after the greatest exercise intensity, then quickly decline. Future studies should examine the effects of higher amylin concentrations in exercise recovery on glucoregulation.
Assuntos
Amiloide/sangue , Glicemia/metabolismo , Exercício Físico/fisiologia , Homeostase , Adulto , Glucagon/sangue , Humanos , Hidrocortisona/sangue , Insulina/sangue , Polipeptídeo Amiloide das Ilhotas Pancreáticas , Masculino , Consumo de Oxigênio , Volume Plasmático , Fatores de TempoRESUMO
CASE REPORT: A patient with extensive burns was intubated with an 8.0 mm internal diameter endotracheal tube (ETT) equipped with a subglottic suction port (Mallinckrodt HiLo Evac). The ETT was secured to a left upper molar with wire sutures throughout the hospitalization course to ensure airway stability. On the 40th day of intubation, the patient exsanguinated and died from a tracheo-innominate artery fistula. Postmortem examination revealed a 1 cm lesion of the left anterior tracheal wall at the position of the ETT tip. The prolonged stationary position of the ETT was considered the primary factor responsible for the fistula. Yet tracheo-innominate artery fistula normally is associated with high cuff pressures rather than with the tube tip. The special ETT construction required for the subglottic suction feature was suspected to have increased tube rigidity and may have played a contributory role. METHODS: The rigidity of the Mallinckrodt HiLo Evac was measured with a mechanical model and compared to 5 other commercially-available ETTs. Rigidity was expressed as the force generated by the ETT tip when the tube curvature was altered by 5 cm and 10 cm of flexion from its resting position. RESULTS: The mean force exerted by the Mallinckrodt HiLo Evac was 10.1 +/- 2.8 g at 5 cm of flexion and 17.7 +/- 5.1 g at 10 cm of flexion. This was significantly greater than all other ETT brands tested (by one-way analysis of variance and Student-Newman-Kuels test, p < 0.05). CONCLUSION: This case of fatal tracheo-innominate artery fistula formation associated with an ETT tip was unusual because of the extended duration of endotracheal intubation and the complexity of the patient's airway management problems. Our data suggest that the higher rigidity of the HiLo Evac ETT may have contributed to fistula development at the tube tip. However, we do not believe that the higher rigidity of the HiLo Evac ETT necessarily poses any greater risk than other ETTs under normal circumstances, in which the tube tip is not fixed in a stationary position for an extended period.
Assuntos
Tronco Braquiocefálico/lesões , Fístula/etiologia , Intubação Intratraqueal/efeitos adversos , Traqueia/lesões , Adulto , Queimaduras/terapia , Evolução Fatal , Humanos , MasculinoRESUMO
Genotype-phenotype association in cystic fibrosis (CF) is difficult because of heterogeneous disease expression. The genotype-phenotype correlation for the 3905insT mutation in comparison to deltaF508 was studied here. Thirty CF patients compound heterozygous for 3905insT were compared to clinical presentation of matched patients homozygous for deltaF508 (1960-1997). Sweat tests, age at diagnosis, at death and at onset of Pseudomonas aeruginosa colonization were analysed. Chrispin-Norman scores and pulmonary function forced expiratory volume in one second (FEV1) determined severity of lung disease. Twenty-five of the patients with 3905insT had deltaF508 as a second mutation and five had another rare mutation. At the age of 15 yrs, 60% of patients with 3905insT had an FEV1 < 60% predicted in comparison to 25% of patients with deltaF508 (p<0.05). Age at death and cumulative survival rate was significantly lower (p<0.05) in the 3905insT than in the deltaF508 group (20.3 and 24.0 yrs, respectively). Age at onset of P. aeruginosa colonization was not different in the study groups. Sweat chloride concentrations were lower in patients homozygous for deltaF508 (105.63+/-15.3 mmol L(-1)) than in patients with 3905insT (119.9+/-22.1 mmol x L(-1)) (p<0.05). Patients compound heterozygous for 3905insT have similar high morbidity and mortality to patients homozygous for deltaF508.
Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Fibrose Cística/genética , Triagem de Portadores Genéticos , Mutação/genética , Adolescente , Adulto , Criança , Pré-Escolar , Fibrose Cística/mortalidade , Feminino , Volume Expiratório Forçado/genética , Genótipo , Humanos , Lactente , Masculino , Fenótipo , Pneumonia Bacteriana/genética , Pneumonia Bacteriana/mortalidade , Infecções por Pseudomonas/genética , Infecções por Pseudomonas/mortalidade , Análise de Sobrevida , Capacidade Vital/genéticaRESUMO
BACKGROUND: We propose a new approach to the measurement of small airway function as an alternative to recordings of maximal expiratory flow-volume (MEFV) curves. OBJECTIVES: A newly developed technique to record isoflow-volume (IFV) curves to be tested against maximal respiratory flow curves. METHODS: An isoflow whistle (IFW; Iflopen) measures the length of a constant expiration after full inspiration. The note of the whistle enables a subject to generate an even expiration, and the isoflow maintenance times at 1 l x s(-1) (IFMT1) and 2 l x s(-1) (IFMT2) are recorded. The accuracy and reproducibility of the IFV technique were evaluated in 17 healthy adults (age 17-55 years) and in 14 asthmatic children (age 6-14 years). Comparisons with standard lung function parameters, such as forced expiratory volume in 1 s (FEV1), maximal expiratory flow at 50% (MEF50) and 25% (MEF25) vital capacity and peak expiratory flow (PEF), obtained with a Wright Peakflow Meter were undertaken in 102 healthy (aged 8-14 years) and 101 asthmatic children (aged 6-17 years). A bronchial challenge test was performed in 13 asthmatic children. RESULTS: The expired volume measured by the IFW showed an acceptable agreement with that of a pneumotachograph (mean error of 4.32% for IFMT1 and 5.93% for IFMT2). In healthy and in asthmatic children, the correlations between FEV1 and IFMT1 or IFMT2 (r = 0.92 and 0.94, respectively) were found to be greater than that between FEV1 and PEF (r = 0.68). During bronchial challenge tests in 13 asthmatic children, the FEV1 decreased to 69% of baseline and IFMT1 to 58% of baseline. CONCLUSIONS: The IFV technique accurately measured airway obstruction and closely followed changes in standard parameters of the MEFV curve.
Assuntos
Obstrução das Vias Respiratórias/diagnóstico , Obstrução das Vias Respiratórias/fisiopatologia , Ventilação Pulmonar , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Curvas de Fluxo-Volume Expiratório Máximo , Pessoa de Meia-Idade , Reprodutibilidade dos TestesRESUMO
This case-controlled study consisted of 2 parts. The objective of part 1 was to determine the relationship between DHEA, body mass index (BMI), and age in young males, young females, and postmenopausal (PM) females. Part 2 examined the effects of estrogen on DHEA by analyzing the relationship between DHEA and age in young females on and off oral contraceptives (OCs) and PM females on and off estrogen or hormone replacement therapy (ERT/HRT). The study was performed at the Obstetrics and Gynecology Clinic, Texas Tech Health Sciences Center-Amarillo, Exercise Physiology Laboratory at Southeastern Louisiana University, and Woman's Health Research Institute, Woman's Hospital, Baton Rouge, LA. Part 1 groups consisted of: (1) young males between the ages of 18 to 40 years; (2) normally cycling females off OCs, ages 18 to 40 years; and (3) PM females older than 40 years not receiving ERT/HRT. Part 2 groups consisted of: (1) normally cycling females on OCs, ages 18 to 40 years;, (2) normally cycling females off OCs, ages 18 to 40 years; (3) PM females 50 years or older not receiving ERT/HRT; and (4) PM females 50 years or older receiving ERT/HRT. The main outcome measure was serum DHEA concentrations. For part 1, there were significant (P <.05) inverse relationships between DHEA and age for young males; young females, off OCs; PM females, no ERT/HRT r = -.44, -.26, and -.25, respectively. There were no significant relationships between DHEA and BMI for any of the groups. DHEA concentrations were significantly higher in young males than young females even after accounting for age. For part 2, DHEA concentrations were significantly higher in young females off OCs compared with young females on OCs, and significantly higher in PM women off ERT/HRT than those on ERT\HRT. There were significant inverse relationships between DHEA and age for young females and PM females on and off ERT/HRT. From these findings, we conclude that there is an inverse relationship between DHEA and age for young males, young females off OCs, and PM females, no ERT/HRT. No relationship between BMI and DHEA was observed in these same 3 groups. These results agree with previous findings in young men, but differ from previous findings in obese young females. The data also suggest that estrogen treatment (OCs and ERT/HRT) suppresses DHEA concentrations in premenopausal and PM females, and that DHEA declines with age in PM females regardless of estrogen treatment.