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1.
Acta Derm Venereol ; 80(2): 140-3, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10877138

RESUMO

Mucocutaneous diseases are common in HIV-infected patients. The aim of the present study was to determine the observed frequency of skin diseases and their prognostic significance for the progression of HIV infection. In a cohort of 150 HIV-infected patients diagnosed from 1986 to 1987 the number of mucocutaneous diseases, the CD4+ cell count, time to development of AIDS and survival time were registered for a period of 5 years. Eight patients were lost for follow-up. In the remaining 142 patients the number of mucocutaneous findings increased markedly during the observation period. The most frequent registered diseases and these with the highest increase were oral candidiasis, hairy leukoplakia, seborrhoeic dermatitis and herpes simplex. On average, 5.2 different diagnoses were registered per patient at the end of the follow-up period. The study showed that the total number of mucocutaneous diseases and the CD4+ cell count were significantly correlated to survival time and time to development of AIDS. The number of mucocutaneous diseases, like the CD4+ count, is an indicator of the immune system and the prognosis of HIV infection.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Infecções Oportunistas Relacionadas com a AIDS/imunologia , Dermatopatias/epidemiologia , Dermatopatias/imunologia , Infecções Oportunistas Relacionadas com a AIDS/diagnóstico , Adulto , Distribuição por Idade , Contagem de Linfócito CD4 , Estudos de Coortes , Dinamarca/epidemiologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Distribuição por Sexo , Dermatopatias/diagnóstico , Taxa de Sobrevida
2.
Acta Derm Venereol ; 78(3): 201-4, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9602227

RESUMO

Forty-three patients with venous leg ulcers were randomized into treatment with either a long- or a short-stretch compression bandage. Subbandage pressure was regularly measured during rest and walking for a period of up to 1 year. The long-stretch bandage was kept on as long as possible, often up to 1 week. It maintained a significantly higher subbandage pressure in the upright position and during passive dependency as well as during walking than the short-stretch bandage after both 2 and 24 h. The difference between maximum and minimum subbandage pressures during walking did not differ between the two groups. Thus, in contrast to general opinion, the short-stretch bandage did not produce a higher peak working pressure than the long-stretch bandage. The pressure decreased in the supine position in both groups.


Assuntos
Bandagens/normas , Dermatoses da Perna/terapia , Úlcera Varicosa/terapia , Velocidade do Fluxo Sanguíneo/fisiologia , Pressão Sanguínea/fisiologia , Ritmo Circadiano/fisiologia , Humanos , Perna (Membro)/irrigação sanguínea , Perna (Membro)/patologia , Dermatoses da Perna/fisiopatologia , Postura/fisiologia , Decúbito Dorsal/fisiologia , Sístole , Fatores de Tempo , Dedos do Pé/fisiologia , Úlcera Varicosa/fisiopatologia , Caminhada/fisiologia , Radioisótopos de Xenônio/uso terapêutico
3.
Acta Anaesthesiol Scand ; 40(5): 636-40, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8792897

RESUMO

BACKGROUND: Subcutaneous blood flow increases during sleep and we evaluated if this increase is affected by epidural anaesthesia. METHODS: Lower leg subcutaneous blood flow was determined by 133Xenon clearance in ten subjects during continuous epidural anaesthesia at L2-L3 including eight hours of sleep, while the upper abdominal subcutaneous blood flow served as control. RESULTS: Epidural anaesthesia to the level of the umbilicus was followed by an increase in the lower leg subcutaneous blood flow from 3.4 (1.8-6.3) to 7.8 (3.6-16.9) ml min-1 100 g-1 (median and range; P < 0.001) and returned to 3.5 (2.4-7.6) ml min-1 100 g-1 after 88 (45-123) min. In contrast, until the period of sleep the upper abdominal region blood flow remained at 5.2 (3.2-6.4) ml min-1 100 g-1. During sleep, lower leg subcutaneous blood flow did not change significantly, but the upper abdominal flow increased to 6.2 (5.2-7.2) ml min-1 100 g-1 after 34 (29-70) min (P < 0.01), and it remained elevated for 125 (100-164) min. CONCLUSIONS: The results indicate that although epidural anaesthesia induced only a temporary increase in lower leg subcutaneous blood flow, it hindered the rise in subcutaneous blood flow normally manifest during early sleep.


Assuntos
Anestesia Epidural , Pele/irrigação sanguínea , Sono/fisiologia , Músculos Abdominais , Adulto , Velocidade do Fluxo Sanguíneo , Feminino , Humanos , Perna (Membro) , Masculino
4.
Am J Cardiol ; 77(4): 281-5, 1996 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-8607409

RESUMO

To examine whether cardiac transplantation would reverse morphologic and hemodynamic changes in peripheral circulation in idiopathic dilated cardiomyopathy, the structure of terminal arterioles and minimal vascular resistance were measured in skin at the dorsum of the foot in the same 14 patients before and 80 +/- 21 (mean +/- SD) days and 387 +/- 46 days after transplantation. The results were compared with data from a group of 16 healthy subjects. Blood flow was measured by the local technetium-99m pertechnetate washout method in a vascular bed relaxed with histamine. Structural microangiopathy (enhanced thickening of the basement membranes) in the arterioles was disclosed in skin biopsies in 11 of 14 patients before transplant, but in none of the 16 control subjects (p < 0.002). These abnormalities were unchanged 80 days after cardiac transplantation. However, arteriolar wall thickening was significantly reduced over the 1-year period after transplantation (p < 0.05), but this was not complete. Transplantation also led to a significant delayed decrease in minimal vascular resistance: before transplantation, 10.1 +/- 3.2 mm Hg.ml-1.100 g.min (mean +/- SD); 80 days after transplantation, 9.3 +/- 3.1 mm Hg.ml-1.100 g.min (p = NS), and 1 year after transplantation 7.6 +/- 2.4 mm Hg.ml-1 100 g.min (p < 0.01). Minimal vascular resistance before and 80 days after transplantation was significantly increased compared with that in healthy control subjects (6.3 +/- 1.7 mm Hg.ml-1 100g.min [p < 0.0003 and p < 0.003, respectively]). However, 1 year after transplantation, minimal vascular resistance was reduced to comparable levels when compared with that in control subjects (p = NS). These results indicate that structural microangiopathy and minimal vascular resistance in skin are improved slowly and gradually within the first year after orthotopic cardiac transplantation in patients with idiopathic dilated cardiomyopathy, however, the remodeling of histopathology is not accompanied by complete normalization.


Assuntos
Cardiomiopatia Dilatada/cirurgia , Transplante de Coração , Pele/irrigação sanguínea , Adulto , Arteríolas/patologia , Cardiomiopatia Dilatada/patologia , Cardiomiopatia Dilatada/fisiopatologia , Feminino , Seguimentos , Pé/irrigação sanguínea , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Fluxo Sanguíneo Regional , Análise de Regressão , Resistência Vascular
5.
Clin Physiol ; 15(6): 611-22, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8590555

RESUMO

The aim of this study was to investigate the possible relationship between variations in local skin and body temperatures, and a subcutaneous hyperaemia response during sleep in humans. Nocturnal subcutaneous blood flow (SBF) was measured in the lower legs of 9 subjects for 8-12 h under outpatient conditions. The core temperature was measured by a tympanic membrane temperature sensor, and the local skin temperature was measured by a skin temperature sensor. The 133Xe wash-out technique with portable CdTe(Cl) detectors was used for measurement of the SBF. The SBF increased significantly (P < 0.0001) after 1 h sleep, with the hyperaemia persisting for 2 h. During the hyperaemic phase, the local skin temperature increased significantly (P < 0.0001) and then decreased again in the post-hyperaemic phase (P < 0.01). The core temperature decreased significantly during the measurement period (P < 0.01). Separate ordinary linear regression analyses revealed no significant correlations between the measured temperature parameters and the blood flow levels during sleep. The results indicate no governing role of the local skin or body temperatures on the local SBF. The local skin temperature increased significantly secondary to the nocturnal subcutaneous hyperaemia (i.e. active vasodilatation), which is believed to be involved in a thermoregulatory effector mechanism.


Assuntos
Temperatura Corporal/fisiologia , Pele/irrigação sanguínea , Sono/fisiologia , Adulto , Feminino , Humanos , Masculino , Fluxo Sanguíneo Regional/fisiologia , Análise de Regressão , Temperatura Cutânea/fisiologia , Temperatura , Radioisótopos de Xenônio
7.
Clin Physiol ; 15(2): 143-9, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7600734

RESUMO

In nine subjects the influence of low (LE: blockade at or below the umbilicus; Th. 10) and high epidural anaesthesia (HE: block above the umbilicus) on vascular tone was evaluated by high frequency ultrasound (20 mHz) determined luminal diameter and a Doppler (8 mHz) assessment of mean blood flow velocity (Vmean) in the dorsalis pedis artery. The LE was induced by 0.5% bupivacain through a catheter at L3-L4, and HE was established by further infusion. Resting blood pressure and heart rate were not affected by LE or HE. One subject developed selective thoracic anaesthesia, and another was blocked on the contralateral side only. In the seven adequately blocked subjects, the luminal diameter of the dorsalis pedis artery increased from 1.70 (1.25-1.93) to 1.90 (1.75-2.23) mm during LE (+12%) and further to 2.08 (1.83-2.96) mm during HE (22%; P < 0.05). The Vmean was similar during control (7[4-26] cm s-1) and LE (12[4-55] cm s-1), but increased during HE to 35(12-78 cm s-1 (+500%; P < 0.05). Thus, arterial blood flow was higher during LE (21[7-98] ml min-1; +263%) and HE (94[21-177] ml min-1; +1175%) than at rest (8[7-36] ml min-1; P < 0.05). This study quantified the importance of sympathetic nerve activity for vascular tone and in turn blood flow in an artery of a resting human limb, as the diameter and Vmean increased with progressive epidural anaesthesia.


Assuntos
Anestesia Epidural , Pé/irrigação sanguínea , Adulto , Anestesia Epidural/métodos , Artérias/efeitos dos fármacos , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Bupivacaína/farmacologia , Feminino , Pé/diagnóstico por imagem , Humanos , Masculino , Valores de Referência , Reologia , Ultrassonografia Doppler
8.
Scand J Clin Lab Invest ; 53(6): 577-83, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8266003

RESUMO

Patients with severe congestive heart failure (CHF) have increased sympathetic nervous activity and altered baroreceptor function, which may influence the diurnal blood pressure rhythm. The 24-h blood pressure profile was measured in 25 patients with severe CHF (mean ejection fraction: 17%) and 25 control subjects. Systemic blood pressure was measured automatically at the arm by a non-invasive blood pressure monitoring system every 15 min. The mean +/- SD systolic blood pressure in CHF patients and controls was during day-time 105 +/- 10 and 130 +/- 11 mm Hg and night-time 97 +/- 10 and 112 +/- 10 mm Hg, i.e. the nocturnal decrease was 9 +/- 6 and 18 +/- 8 mm Hg, respectively (p < 0.0005 for all). The subjects could be divided into two groups: dippers and non-dippers, with and without a relative decrease in nocturnal systolic blood pressure > 10%. There was significantly more non-dipping CHF patients (16) than controls (5) (p < 0.01). Systolic blood pressure was in CHF dippers vs. non-dippers during day-time: 108 +/- 7 vs. 104 +/- 12 mm Hg (NS) and night-time: 92 +/- 7 vs. 99 +/- 11 mm Hg (p = 0.08). The nocturnal decrease was 16 +/- 3 vs. 5 +/- 4 mm Hg and the relative nocturnal decrease 15 +/- 3 vs. 5 +/- 3% (p < 0.00001 for both). It is concluded that patients with severe congestive heart failure can be divided into two groups: dippers and non-dippers, with and without a normal decrease in nocturnal blood pressure.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Pressão Sanguínea , Ritmo Circadiano , Insuficiência Cardíaca/fisiopatologia , Adulto , Frequência Cardíaca , Humanos , Pessoa de Meia-Idade
9.
Clin Sci (Lond) ; 84(3): 297-304, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8384952

RESUMO

1. The local subcutaneous adipose tissue blood flow was measured simultaneously in the right and left lower legs of 10 normal human subjects under out-patient nocturnal conditions. The 133Xe-wash-out technique, portable CdTe(Cl) detectors and a portable data-storage unit were used for the measurement of blood flow. 2. The purpose of the study was to unveil the possible role of centrally controlled nerve fibres to the measurement area as mediators of a previously described nocturnal subcutaneous hyperaemia of 2 h duration. Therefore, before the sleeping period, a local nervous blockade was applied immediately proximal to the isotope depot on the right lower leg by the injection of approximately 15 ml of bupivacaine (5 mg/ml) subcutaneously. 3. Control experiments revealed blockade of the baroreceptor vasoconstrictor reflex activity 4 h after application of the local nervous blockade in three subjects examined. 4. Identical nocturnal isotope-wash-out curves were recorded from the two legs. Subcutaneous blood flow was found to increase significantly (P < 0.0001) after approximately 1 h of sleep and the hyperaemia persisted for 2 h. 5. A significant positive correlation was detected between the latency periods from going to bed until the onset of the hyperaemia in the right and left lower legs (P < 0.001, r = 0.95). 6. No significant difference could be detected between the relative blood flow increase during the hyperaemic phase in the right and left lower legs (P = 0.83). 7. It is concluded that the present data seem to rule out a central nervous factor(s) as the eliciting mechanism of the nocturnal subcutaneous hyperaemia.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Tecido Adiposo/irrigação sanguínea , Perna (Membro)/irrigação sanguínea , Bloqueio Nervoso , Nervos Periféricos/fisiologia , Sono/fisiologia , Adulto , Feminino , Humanos , Hiperemia/fisiopatologia , Masculino , Tempo de Reação , Fluxo Sanguíneo Regional/fisiologia , Radioisótopos de Xenônio
10.
J Appl Physiol (1985) ; 73(4): 1246-52, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1447066

RESUMO

Nocturnal subcutaneous adipose tissue blood flow rate was measured in the lower legs of 10 normal human subjects together with systemic arterial blood pressure, heart rate, and registration of sleep stages under ambulatory conditions. The 133Xe washout technique, portable CdTe(Cl) detectors, and a portable data storage unit were used for measurement of blood flow rates. The sleep recordings were performed with a portable computerized sleep analysis system. In accordance with the results of previous studies, a hyperemic blood flow rate phase (mean increase 140%) for 100 min was observed approximately 60 min after the subjects went to bed. The moment of onset of the hyperemic phase was closely related to the moment of onset of the first episode of deep sleep (stages 3 and 4). There was a significant (P < 0.01) overrepresentation of deep sleep in the hyperemic phase compared with adjacent phases, and rapid-eye-movement sleep predominantly occurred in the latter part of the night, when the subcutaneous blood flow rate was stable. The results of the present study are in accordance with current theories of the interrelationship between the thermoregulatory and the arousal state control systems and, thus, might suggest that the nightly subcutaneous hyperemia represents a thermoregulatory effector mechanism.


Assuntos
Perna (Membro)/irrigação sanguínea , Pele/irrigação sanguínea , Fases do Sono/fisiologia , Tecido Adiposo/irrigação sanguínea , Adulto , Nível de Alerta/fisiologia , Pressão Sanguínea/fisiologia , Eletroencefalografia , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Fluxo Sanguíneo Regional/fisiologia , Análise de Regressão , Radioisótopos de Xenônio
11.
Respir Med ; 86(2): 93-6, 1992 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1615190

RESUMO

This double-blind, placebo-controlled, crossover study was performed to evaluate the effect of terbutaline administered by a turbuhaler on spirometry, walking distance and dyspnoea during exercise in patients with chronic obstructive lung disease (COLD) and to evaluate relationships between changes in spirometry and working indices. The patients had a maximum reversibility in FEV1 of 15% predicted, and to ensure the option of studying correlations between changes in spirometry and working indices in patients with COLD a wide range of reversibility in FVC was ensured. Eighteen patients (M, 12; F, 6; mean age 68.5 years) were included in the trial. Mean baseline FEV1 was 0.921 and FVC 2.081. Six minutes unpaced walking distance on flat ground (WD) and Brog dyspnoea index scale (BS) were used as working indices. Baseline mean WD was 467.9 m, and median BS 3.2. No significant difference was found in the effect of terbutaline compared to placebo on the spirometry findings or WD. However, BS during exercise improved significantly on the terbutaline day. No significant correlation was found between changes in working indices and change in spirometry. Thus, the use of exercise testing and dyspnoea-scoring may reveal patients who benefit from acute bronchodilation without significant improvement in lung function.


Assuntos
Pneumopatias Obstrutivas/tratamento farmacológico , Terbutalina/uso terapêutico , Administração por Inalação , Idoso , Método Duplo-Cego , Teste de Esforço/efeitos dos fármacos , Feminino , Volume Expiratório Forçado/efeitos dos fármacos , Humanos , Locomoção/efeitos dos fármacos , Pneumopatias Obstrutivas/fisiopatologia , Masculino , Terbutalina/administração & dosagem , Capacidade Vital/efeitos dos fármacos
12.
Clin Sci (Lond) ; 82(1): 47-54, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1310917

RESUMO

1. Lower-leg subcutaneous adipose tissue blood flow rates were measured over 12-20 h under ambulatory conditions by means of the 133Xe-washout technique in nine paraplegic men, all with complete spinal cord lesions at or below the Th 6 level, and in nine age-matched healthy men. Portable CdTe(Cl) detectors and data-storage units were used. 2. The central and local sympathetic vasoconstrictive activity at the lower leg was measured under laboratory conditions by means of the 133Xe-washout technique and a stationary NaI(Tl) detector system. 3. The paraplegic men were found to have intact central and local sympathetic vasoconstrictive activity in their lower legs. Moreover, they all had a nocturnal hyperaemic blood flow phase of the same magnitude and duration as the control subjects. 4. The possibility that the somaesthetic nerves play a role in the hyperaemic response could be excluded, as all the paraplegic men suffered from complete lower-leg somaesthetic denervation. 5. A significant correlation was found between the time of going to bed and the nightly hyperaemic response in the right and left lower legs (P less than 0.01). 6. It is concluded that the present data are in accordance with the concept of a central nervous or humoral elicitation of nocturnal hyperaemia, although local metabolic and other factors might participate as well. Paraplegic men have an intact regulation of the postural and nocturnal changes in peripheral blood flow whether of central sympathetic or humoral origin.


Assuntos
Tecido Adiposo/irrigação sanguínea , Ritmo Circadiano/fisiologia , Perna (Membro)/irrigação sanguínea , Paraplegia/fisiopatologia , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Postura/fisiologia , Fluxo Sanguíneo Regional/fisiologia , Vasoconstrição/fisiologia
13.
J Dermatol Sci ; 3(1): 42-5, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1591226

RESUMO

Some data have demonstrated a substantial subdermal accumulation of topically applied drugs in animals. The aim of this study was to evaluate a possible effect of epicutaneously applied clobetasol propionate on blood flow in human subcutaneous adipose tissue. Nine healthy subjects were studied. The 133Xenon wash-out method was used for the measurement of subcutaneous blood flow. Resting blood flow and the local blood flow regulatory mechanisms, autoregulation of blood flow and the veno-arteriolar reflex, were assessed prior to treatment and were measured following 24, 48 and 72 h of treatment. The results demonstrated no effect of clobetasol propionate on resting subcutaneous blood flow or the local regulatory mechanisms.


Assuntos
Tecido Adiposo/irrigação sanguínea , Clobetasol/análogos & derivados , Absorção Cutânea/efeitos dos fármacos , Fenômenos Fisiológicos da Pele , Tecido Adiposo/efeitos dos fármacos , Administração Tópica , Adulto , Clobetasol/administração & dosagem , Clobetasol/farmacologia , Feminino , Humanos , Masculino , Pomadas , Fluxo Sanguíneo Regional/efeitos dos fármacos , Pele/efeitos dos fármacos , Fatores de Tempo , Radioisótopos de Xenônio
14.
Diabet Med ; 9(1): 38-43, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1551308

RESUMO

Nocturnal fluctuations in subcutaneous blood flow in the lower leg and foot were measured during sleep in Type 1 diabetic patients without autonomic neuropathy. Subcutaneous blood flow was measured, simultaneously, 100 mm above the malleolus on the medial aspect of the right lower leg and at the dorsum of the left foot in 10 diabetic patients, and on the right lower leg only in 10 normal human subjects over 12-20 h. The 133Xe wash-out technique, portable CdTe (Cl) detectors and a portable data storage unit were used. The tracer depots were applied by means of the epicutaneous, atraumatic labelling technique. In diabetic patients, subcutaneous blood flow increased 102 +/- 68% in the lower leg and 111 +/- 98% in the foot at 113 +/- 32 min and 107 +/- 37 min, after going to sleep. The hyperaemic phase lasted 128 +/- 43 min and 150 +/- 42 min, respectively. The hyperaemic response was not different from that in the control subjects (89 +/- 61%). There was no significant correlation between the absolute hyperaemia in the leg and that in the foot. In conclusion, Type 1 diabetic patients without autonomic neuropathy have normal nocturnal hyperaemia during sleep.


Assuntos
Ritmo Circadiano , Diabetes Mellitus Tipo 1/fisiopatologia , Angiopatias Diabéticas/fisiopatologia , Pé/irrigação sanguínea , Hiperemia/fisiopatologia , Perna (Membro)/irrigação sanguínea , Tecido Adiposo/irrigação sanguínea , Adulto , Feminino , Humanos , Hiperemia/etiologia , Masculino , Pulso Arterial , Valores de Referência , Fluxo Sanguíneo Regional , Sono/fisiologia , Radioisótopos de Xenônio
15.
Clin Physiol ; 11(6): 491-9, 1991 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1769184

RESUMO

The purpose of the study was to investigate possible regional variations in recently discovered nocturnal fluctuations in subcutaneous blood flow rates. Approximately 90 min after going to sleep, a 100% blood flow rate increment, lasting about 100 min, has been demonstrated in the distal and medial aspect of the right lower leg of normal human subjects. In the present study subcutaneous adipose tissue blood flow rates were measured simultaneously in the right and left lower legs of 16 normal human subjects over 12-20 h ambulatory conditions. The 133Xe wash-out technique, portable CdTe(Cl) detectors and a portable data storage unit were used. The tracer depots were applied on the medial aspects of the right lower leg and on the medial (series 1) and lateral (series 2) aspect of the left lower leg 10 cm proximal to the malleolar level by means of the epicutaneous, atraumatic labelling technique. A nocturnal hyperaemic response was demonstrated at both the medial and lateral aspect of the leg. As for the degree of hyperaemia and the absolute blood flow rates in the different phases, there were some deviations between the medial and the lateral locations. However, a highly significant positive correlation was observed in both series concerning the duration of the period from going to bed until the hyperaemia phase (P less than 0.001). The mechanisms involved in the nightly subcutaneous hyperaemia are at present unknown. The sudden, synchronized increase in nocturnal subcutaneous blood flow points to a central nervous or humoral elicitation, although local metabolic factors might participate as well.


Assuntos
Ritmo Circadiano/fisiologia , Fenômenos Fisiológicos da Pele , Pele/irrigação sanguínea , Adulto , Velocidade do Fluxo Sanguíneo/fisiologia , Sistema Nervoso Central/fisiologia , Feminino , Humanos , Perna (Membro) , Masculino , Microcirculação/fisiologia , Sono/fisiologia , Radioisótopos de Xenônio
16.
Br J Dermatol ; 125(5): 436-42, 1991 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1751349

RESUMO

The blood flow rate in subcutaneous adipose tissue was measured on the lower legs of 11 patients with chronic lower-leg venous insufficiency and ulceration and in eight age-matched control subjects for 12-20 h, under ambulatory conditions, using the 133Xe wash-out technique with portable Cadmium telluride (CdTe(Cl)) detectors. In both groups, the change from an upright to a supine position at the beginning of the night period elicited an instantaneous increment in the blood flow rate of 30-40% with a decrease in the central and local postural sympathetic vasoconstrictor activity. After approximately 1 h of sleep, a considerable increase in blood flow rate was seen in both patient and control groups which persisted for nearly 100 min. In the patient group, the mean increase was 137% compared to a mean increase of 68% in the control group (P less than 0.01). The blood flow then returned to the same level as at the beginning of the night and remained stable until the subjects woke in the morning. The differences between this nocturnal hyperaemic phase and the adjacent phases were highly significant in both groups (P less than 0.0001 and P less than 0.005, respectively). The blood flow levels measured on the second day were of the same magnitude as those registered on the first day. The mean values of the wash-out rate constants (k) of the two groups were of the same magnitude in all phases of subcutaneous blood flow level, except in the hyperaemic phase, where it was significantly higher in the patient group (P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Perna (Membro)/irrigação sanguínea , Úlcera Varicosa/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Ritmo Circadiano , Feminino , Humanos , Masculino , Fluxo Sanguíneo Regional/fisiologia , Insuficiência Venosa/fisiopatologia , Radioisótopos de Xenônio
17.
Am J Physiol ; 261(4 Pt 2): H982-8, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1928417

RESUMO

Subcutaneous adipose tissue blood flow rate, together with systemic arterial blood pressure and heart rate under ambulatory conditions, was measured in the lower legs of 15 normal human subjects for 12-20 h. The 133Xe-washout technique, portable CdTe(Cl) detectors, and a portable data storage unit were used for measurement of blood flow rates. An automatic portable blood pressure recorder and processor unit was used for measurement of systolic blood pressure, diastolic blood pressure, and heart rate every 15 min. The change from upright to supine position at the beginning of the night period was associated with a 30-40% increase in blood flow rate and a highly significant decrease in mean arterial blood pressure and heart rate (P less than 0.001 for all). Approximately 100 min after the subjects went to sleep an additional blood flow rate increment (mean 56%) and a simultaneous significant decrease in mean arterial blood pressure (P less than 0.001) were observed. The duration of this hyperemic phase was 116 min. A highly significant reduction of the subcutaneous vascular resistance (50%) was demonstrated during the hyperemic blood flow rate phase compared with the surrounding phases (P less than 0.0001). The synchronism of the nocturnal subcutaneous hyperemia and the decrease in systemic mean arterial blood pressure point to a common, possibly central nervous or humoral, eliciting mechanism.


Assuntos
Pressão Sanguínea , Ritmo Circadiano , Frequência Cardíaca , Perna (Membro)/irrigação sanguínea , Adulto , Feminino , Humanos , Masculino , Fluxo Sanguíneo Regional , Análise de Regressão , Radioisótopos de Xenônio
18.
Clin Physiol ; 11(4): 353-65, 1991 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1914438

RESUMO

Possible sources of error during long-term measurements of subcutaneous blood flow rate with the portable CdTe(Cl) detector system were ruled out in the present study. Local blood flow rates were recorded in the lower legs of normal human subjects by means of the 133Xe wash-out technique. A good correlation was found between the portable CdTe(Cl) and stationary NaI(Tl) detector systems both prior to (r = 0.88, P less than 0.0001) and after (r = 0.68, P = 0.07) day over night (12 h) measurements. Identical post-ischaemic reactive hyperaemia could be demonstrated by both detector systems 12 h after the application of the isotope depot. This indicates that blood flow rates and vascular reactivity can be measured over 12 h by the portable CdTe(Cl) detector. Identical results were obtained during the 12-h measurements performed with the portable CdTe(Cl) detector attached directly to the skin surface and with the detector elevated above the skin surface. Therefore, geometrical changes were without any influence on our measurements. We conclude that measurements of subcutaneous blood flow rates in the lower leg of human subjects can be performed under out-patients conditions by means of the 133Xe wash-out technique and portable CdTe(Cl) detectors. A skin area greater than or equal to 4 cm should be labelled by means of the atraumatic, epicutaneous labelling technique and the detector attached directly to the skin surface with a single layer of a 20-micron thick gas-tight Mylar membrane interposed between the skin surface and the detector. The investigation of the subcutaneous blood flow rate should not be initiated until at least 90 min after labelling.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Ritmo Circadiano/fisiologia , Adulto , Cádmio , Cloro , Equipamentos e Provisões , Feminino , Humanos , Perna (Membro)/irrigação sanguínea , Perna (Membro)/fisiologia , Masculino , Métodos , Telúrio , Fatores de Tempo
19.
Am J Physiol ; 260(2 Pt 2): H480-5, 1991 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1996691

RESUMO

Subcutaneous adipose tissue blood flow rate was measured in the lower leg of 22 normal human subjects over 12- to 20-h ambulatory conditions. The 133Xe washout technique, portable CdTe(Cl) detectors, and a portable data storage unit were used. The tracer depot was applied on the medial aspect of the right lower leg 10 cm proximal to the malleolar level by means of the epicutaneous, atraumatic labeling technique. The change from upright to supine position from day 1 in the beginning of the night period elicited an instantaneous blood flow rate increment of 30-40% in accordance with a decrease in central and local postural sympathetic vasoconstrictor activity. During sleep, characteristic variations in subcutaneous blood flow were disclosed. The 133Xe washout curve could be divided into three segments with significantly different slopes. Approximately 90 min after the subject went to sleep, an additional blood flow rate increment of considerable magnitude was observed. The mean increase was 84%, but in several cases a greater than 200% increment was measured (maximum 244%). The intra-individual coefficient of variation for the nocturnal blood flow response was in triplicate measurements 25% (n = 9). The hyperemic phase lasted approximately 100 min after which the blood flow rate returned to the level measured at the beginning of the night period. The blood flow rates measured on the second day did not differ from those on the first day. Control measurements performed under similar thermal conditions, but with the subjects kept awake, did not reveal any hyperemic phases. This points toward changes in cardiovascular regulatory mechanisms during sleep.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Ritmo Circadiano , Perna (Membro) , Pele/irrigação sanguínea , Tecido Adiposo/irrigação sanguínea , Adulto , Análise de Variância , Feminino , Humanos , Individualidade , Masculino , Valores de Referência , Fluxo Sanguíneo Regional , Reprodutibilidade dos Testes , Sono/fisiologia , Fatores de Tempo
20.
Br J Dermatol ; 124(2): 177-80, 1991 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2004002

RESUMO

The blood flow in the subcutaneous adipose tissue of the lower leg of eight normal subjects and 19 patients with chronic venous insufficiency was measured. The 133Xe-washout technique was used with portable CdT1(C1) detectors and a data storage unit. Only those patients with ulcers and a systolic blood pressure at the toe of greater than or equal to 60 mm were investigated. In the controls the relative blood flow during sitting was 0.61 (range 0.35-0.80). In the patients it was 0.46 (range 0.22-0.87). This difference was not significant. During walking the blood flow increased in controls as well as in the patients compared to the value determined in the sitting position (P = 0.0078 and P = 0.0028, respectively, Wilcoxon matched-pairs test). The relative blood-flow rate during walking was 0.96 (range 0.60-1.58) in the controls, and 1.04 (range 0.49-1.46) in the patients. The difference between the normal subjects and the patients was not significant (P = 0.79). We conclude from our studies that patients with venous insufficiency are able to increase their blood flow during walking to the same extent as normal controls.


Assuntos
Tecido Adiposo/irrigação sanguínea , Perna (Membro)/irrigação sanguínea , Insuficiência Venosa/fisiopatologia , Caminhada , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Humanos , Pessoa de Meia-Idade , Fluxo Sanguíneo Regional/fisiologia , Radioisótopos de Xenônio
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