RESUMO
OBJECTIVE: In order to determine the relative locations of puborectalis/pubovisceralis (PR/PV) and iliococcygeus (IC) muscles, we undertook an analysis of four-dimensional (4D) ultrasound datasets obtained after suburethral sling placement. METHODS: This was a retrospective analysis of ultrasound volume data obtained in 110 women after undergoing the Monarc suburethral sling procedure. Tomographic ultrasound imaging (TUI) was performed with eight slices in the axial plane, from 5 mm below to 12.5 mm above the plane of minimal hiatal dimensions. Hyperechogenic tape material was rated as absent, present or as producing an anechoic acoustic shadow overlying the muscle in each slice. RESULTS: Slices 7 and 8 virtually always showed evidence of the implant or its acoustic shadow on the pelvic sidewall (98% for slice 8 and 96% for slice 7), suggesting that these slices are located at the level of the obturator foramen. This implies that these slices do not generally contain PR/PV muscle, but rather IC muscle. CONCLUSION: On standardized tomographic imaging of the levator hiatus and muscle, slices located ≥ 1 cm over the plane of minimal dimensions are very likely to contain IC muscle rather than PR/PV muscle.
Assuntos
Diafragma da Pelve/diagnóstico por imagem , Prolapso de Órgão Pélvico/diagnóstico por imagem , Tomografia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pessoa de Meia-Idade , Prolapso de Órgão Pélvico/cirurgia , Estudos Retrospectivos , Slings Suburetrais , UltrassonografiaRESUMO
BACKGROUND: No one has previously examined the relation of serum total cholesterol, serum triglycerides and fasting plasma glucose to colorectal carcinoma in situ. METHODS: A case-control study was performed with 129 cases of colorectal carcinoma in situ and 258 matched controls among examinees undergoing a health check-up in Tokyo from January 1991 to March 1993. RESULTS: There was a significant, positive association between serum total cholesterol levels and the risk of colorectal carcinoma in situ after adjustment for age, sex, body mass index, smoking status and alcohol consumption. Serum triglyceride levels were significantly and positively associated with colorectal carcinoma in situ risk regardless of adjustment for the above covariates. Although there was no clear relation between colorectal carcinoma in situ and fasting plasma glucose levels, a modest increase of colorectal carcinoma in situ risk was observed in the highest category (> or =116 mg/dl) of fasting plasma glucose levels. CONCLUSIONS: The findings suggest a positive association between serum total cholesterol levels and the risk of colorectal cancer, rather than an inverse relation. The strong association with serum triglyceride levels and the weak association with fasting plasma glucose levels support the hypothesis that hyperinsulinaemia may play an important role in colorectal carcinogenesis.
Assuntos
Glicemia/análise , Carcinoma in Situ/sangue , Colesterol/sangue , Neoplasias do Colo/sangue , Neoplasias Retais/sangue , Triglicerídeos/sangue , Adulto , Idoso , Carcinoma in Situ/epidemiologia , Estudos de Casos e Controles , Neoplasias do Colo/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Retais/epidemiologia , Fatores de RiscoRESUMO
OBJECTIVES: In Japan controversy exists as to whether or not the risk factors for ischemic heart disease (IHD) are the same as in western countries. We conducted a case-control study on IHD to clarify the risk factors in males in an urban area of Japan using our automated multiphasic health testing and services (AMHTS) system. METHOD: Cases were the clients who took the health check-up between January 1987 and July 1994 and had onset of IHD after the check-up. For each case five clients were selected as controls by conditional matching. The check-up data were compared between cases and controls 11 years, 6 years and just before the onset of the heart diseases. RESULTS: The statistically significant items were as follows: (1) Eleven years before the onset: Total cholesterol (T-Chol) for myocardial infarction (MI), and fasting blood sugar (FBS) for angina pectoris (AP). (2) Six years before the onset: T-Chol, electrocardiographic (ECG) findings and the complaint of palpitation or breathlessness for MI, and FBS and palpitation or breathlessness for AP. (3) Just before the onset: T-Chol, the complaint of chest pain, FBS, smoking index and hypertensive status for MI and palpitation or breathlessness, ECG findings, chest pain, systolic blood pressure and erythrocyte sedimentation rate at 60 minutes for AP. In conclusion, the risk factors for MI in males in an urban area of Japan are the same as in western countries. The most significant risk factor for AP in males in an urban area of Japan is fasting blood sugar.
Assuntos
Isquemia Miocárdica/prevenção & controle , Adulto , Idoso , Análise de Variância , Estudos de Casos e Controles , Humanos , Japão/epidemiologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/epidemiologia , Razão de Chances , Fatores de RiscoRESUMO
A previous report was concerned with the evaluation of quality of life using a Health Promotion System for the Elderly. In the present report, we describe one part of that system: a subjective symptoms acquisition and reporting system. The main purpose of this system is to permit any physician or nurse to uniformly employ questionnaires to acquire accurate subjective symptoms. This system is applied in three steps. First, the subjective answers to 21 questions displayed on a personal computer are obtained. These answers correspond to the basic subjective symptoms. Second, if a basic subjective symptom is "positive", more detailed questions are automatically generated. Finally, clear sentences regarding subjective symptoms are generated and output as a "finding report". This information is helpful to physicians and nurses in their health-counseling work. An artificial intelligence (AI) program based on "XpertRule" produces detailed questions which are generated by an interactive questionnaire using branching logical rules.
Assuntos
Inteligência Artificial , Avaliação Geriátrica , Promoção da Saúde/métodos , Anamnese/métodos , Qualidade de Vida , Idoso , Humanos , Japão , Inquéritos e QuestionáriosRESUMO
OBJECTIVE: To provide automated advice for lifestyle adjustment based on an assessment of the results of a questionnaire and medical examination or health checkup data. METHODS: A system was developed that gathers data based on questions regarding weight gain, exercise, smoking, sleep, eating habits, salt intake, animal fat intake, snacks, alcohol, and oral hygiene; body mass index, resting blood pressure, fasting blood sugar, total cholesterol, triglycerides, uric acid and liver function tests. Based on the relationships between the lifestyle data and the health checkup data, a health assessment sheet was generated for persons being allocated to a multiple-risk-factor syndrome group. RESULTS: Health assessment and useful advice for lifestyle improvement were automatically extracted with the system, toward the high risk group for lifestyle related diseases. The system is operational. CONCLUSIONS: We developed a health guidance support system for lifestyle improvement. In comparison with conventional, limited advice methods, we developed a practical system that defined the necessity for lifestyle improvement more clearly, and made giving advice easier.
Assuntos
Promoção da Saúde , Estilo de Vida , Inquéritos e Questionários , Aconselhamento , Humanos , Japão , SoftwareRESUMO
The purpose of this study is to evaluate the baroreflex function using lower body negative pressure (LBNP) and neck suction in young normotensive men with or without a family history of hypertension. Twenty-two young normotensive men with a family history of hypertension (FH+) and eight young normotensive men who had no family history of hypertension (FH-) were studied. FH(+) consisted of men who had a family history of hypertension within second degree relatives. We studied cardiopulmonary baroreflex function using LBNP and carotid sinus baroreflex function using neck suction and evaluated the reflex function under stimulated conditions using both LBNP and neck suction at the same time. Systolic arterial pressure (SAP)(F = 5.42, p < 0.0001) and pulse pressure (PP)(F = 15.57, p < 0.0001) decreased similarly in both groups in response to LBNP. SAP and PP responses to LBNP were not significantly affected by the family history of hypertension. Diastolic arterial pressure (DAP) increased (F = 2.89, p < 0.005) in both groups. There was a relationship between the LBNP level and family history of hypertension (F = 2.53, p < 0.013), and the increment in DAP during LBNP -30, -40 mmHg was larger in the FH(+) group. Through mean arterial pressure (MAP) was not effected by LBNP, there LBNP level was related to the family history of hypertension (F = 2.23, p < 0.02). Heart rate increased progressively (F = 25.7, p < 0.0001) with increasing levels of LBNP; however, these changes did not differ significantly in either group.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Barorreflexo/fisiologia , Hipertensão/genética , Adulto , Teste de Esforço , Hemodinâmica , Humanos , Pressão Negativa da Região Corporal Inferior , MasculinoRESUMO
To investigate the effects of daily mild supine exercise on physical performance capacity identified as maximal oxygen uptake rate (VO2max) after 20 days bedrest, 3 male students performed a supine pedaling at 40% intensity of VO2max for one hour every day, while 6 male and 5 female students were control. Before and after the bedrest, muscle mass and strength of exercising leg and cardiovascular responses during -40mmHg lower body negative pressure (LBNP) and moderate upright cycling exercise were measured. Despite the exercise programme VO2max was similarly decreased to the control subjects after bed-rest. The delta VO2max was correlated to delta % left ventricular fractional shortening during LBNP, and also % delta VO2max to % delta stroke volume of the moderate exercise (both p<0.05). The exercise programme should be too weak to maintain cardiovascular functions and thus to present the decrease in VO2max against prolonged bedrest as well as weightlessness stress.
Assuntos
Repouso em Cama/efeitos adversos , Exercício Físico/fisiologia , Músculo Esquelético/fisiologia , Consumo de Oxigênio/fisiologia , Adulto , Terapia por Exercício/métodos , Feminino , Frequência Cardíaca/fisiologia , Humanos , Pressão Negativa da Região Corporal Inferior , Masculino , Contração Muscular/fisiologia , Músculo Esquelético/anatomia & histologia , Contração Miocárdica/fisiologia , Esforço Físico/fisiologia , Volume Sistólico/fisiologia , Decúbito DorsalRESUMO
Anesthetic management of patients with dilated cardiomyopathy (DCM) was analyzed. From January 1991 to June 1993, we had 7 patients with DCM; 5 patients received general anesthesia and 2 patients received spinal anesthesia. General anesthesia was induced and maintained generally with diazepam and fentanyl. There were two patients who suffered from intraoperative arrhythmia. One patient who received spinal anesthesia suffered from ventricular fibrillation suddenly before the operation and we performed cardiopulmonary resuscitation successfully but the operation was cancelled. One patient who underwent emergency operation for gastric perforation suffered supraventricular tachycardia during the operation, and we were required to use antiarrhythmic agent that was thought to be deleterious to cardiac function. There was no patient who died perioperatively. There was one patient in the group IV of classification of Inoh which predicts the highest risk of dying from cardiac failure. In conclusion, it is important to control arrhythmia during the management of patients with DCM under anesthesia.
Assuntos
Anestesia Geral , Cardiomiopatia Dilatada/cirurgia , Adulto , Idoso , Raquianestesia , Arritmias Cardíacas/terapia , Humanos , Complicações Intraoperatórias/terapia , Masculino , Pessoa de Meia-IdadeRESUMO
The high activity of the cardiac Na+-Ca2+ exchanger has led to the suggestion that it plays an important role in the regulation of myocardial contractility. We have proposed that exercise training increases stroke volume as a consequence of an enhanced contractility caused by an adaptation in Ca2+ transport across the cardiac plasma membrane (sarcolemma). The present study examined the possibility that the Na+-Ca2+ exchanger in heart muscle is modified in response to training. Sprague-Dawley rats (female, n = 72) were randomly divided into exercise-trained (T) and sedentary control (C) groups. As a result of the 11-wk treadmill-training paradigm, group T had a 7.6% higher (P less than 0.005) heart-to-body weight ratio and a 36% increase (P less than 0.01) in gastrocnemius mitochondrial enzyme activity. Na+-Ca2+ exchange was studied in highly purified sarcolemmal vesicles using rapid-quenching techniques. The absolute initial rate of uptake was significantly higher in T vs. C at calcium concentrations [( Ca2+]) ranging from 10 to 80 microM. This increased uptake appears to be due solely to the fact that the apparent Km of the myocardial Na+-Ca2+ exchanger for Ca2+ was significantly lower in T vs. C (15.7 +/- 1.1 vs. 36.1 +/- 2.6 microM), since the maximum velocity was unchanged. The observed increase in the affinity of the exchanger for Ca2+ is not attributable to group differences in vesicular purity, cross-contamination, or passive Ca2+ efflux. This observation is consistent with observed alterations in sarcolemmal composition in response to exercise training. We propose that the modification of the Na+-Ca2+ exchanger may play an important role in the adaptation of the heart to exercise.
Assuntos
Cálcio/metabolismo , Proteínas de Transporte/metabolismo , Coração/fisiologia , Esforço Físico , Sarcolema/metabolismo , Animais , Cinética , Músculos/metabolismo , Músculos/fisiologia , Miocárdio/metabolismo , Ratos , Ratos Endogâmicos , Valores de Referência , Trocador de Sódio e CálcioRESUMO
This study compared Na(+)-Ca2+ exchange from the hearts of rainbow trout with that from canines. In several respects, trout cardiac Na(+)-Ca2+ exchange is functionally similar to that from dogs and other mammals. Trout cardiac Na(+)-Ca2+ exchange is stimulated approximately 200% after 30-min incubation with 10 micrograms/ml chymotrypsin at 21 degrees C, similar to mammals. On the other hand, both the temperature and pH dependencies are strikingly different between the trout and canine myocardial Na(+)-Ca2+ exchange. While canine heart Na(+)-Ca2+ exchange exhibits a Q10 of greater than 2 (similar to values observed in other mammals), that from trout is relatively insensitive to temperature with a Q10 of approximately 1.2. The absolute rates of Na(+)-Ca2+ exchange in trout heart are four- to sixfold higher than that in mammals when measured at 7 degrees C. Furthermore, the temperature insensitivity of trout myocardial Na(+)-Ca2+ exchange is retained when the exchanger is reconstituted into an asolectin bilayer, suggesting that this property is intrinsic to the protein and not dependent on species differences in lipid bilayer composition. Trout Na(+)-Ca2+ exchange is not markedly stimulated by alkaline pH, in contrast to mammals, and this characteristic is also maintained after reconstitution. Western blots of trout cardiac sarcolemma run on 7.5% sodium dodecyl sulfate-polyacrylamide gel electrophoresis react with antibodies raised against the canine Na(+)-Ca2+ exchanger with a similar pattern of bands (70, 120, and 160 kDa). Furthermore, a cDNA probe from canine Na(+)-Ca2+ exchanger hybridizes on Northern blots of trout heart mRNA to a 7-kb band, similar to that in mammals. Thus, while important functional differences in Na(+)-Ca2+ exchange exist between trout and mammalian hearts, the molecular basis is not yet known.
Assuntos
Proteínas de Transporte/metabolismo , Miocárdio/metabolismo , Animais , Western Blotting , Cálcio/metabolismo , Quimotripsina/farmacologia , Cães , Concentração de Íons de Hidrogênio , RNA/metabolismo , Sódio/farmacologia , Trocador de Sódio e Cálcio , Temperatura , TrutaRESUMO
OBJECTIVE: To elucidate the effect of long-term body weight changes on the subsequent incidence of hypertension in a large sample of community-residing Japanese males and females. METHODS: Subjects were 3431 men and 2409 women, between 30 and 69 y old, who underwent annual periodic health examinations from 1987 (baseline year) until 1996. They were free from hypertension during the first 5 y from the baseline year. Body weight change index between 1987 and 1992 was the body mass index (BMI) (weight (kg) over height (m) squared) slope. Multiple logistic analysis was performed to assess the effect of BMI slope on the incidence of hypertension during the subsequent 5 ys (1992-1996), while controlling for baseline age, BMI, systolic blood pressure (SBP), diastolic blood pressure (DBP) and smoking habit. RESULTS: During the first 5 y, the prevalence of overweight males (25.0< or =BMI<30.0) significantly increased from 18.4 to 23.5% in males and from 10.4 to 14.1% in females. In all, 11.7% of the males and 8.9% of the females developed hypertension between 1992 and 1996. Those who developed hypertension had a significantly higher baseline age, BMI, SBP and DBP both in males and females. The baseline smoking rate among the females who developed hypertension was significantly lower than those who did not develop the hypertension. After adjustment of these covariables by the multiple logistic analysis, the BMI slope was positively correlated with the incidence of hypertension both in females and males significantly. CONCLUSIONS: Weight gain increased the risk of developing hypertension independent of age and blood pressure level among relatively lean Japanese men and women.
Assuntos
Peso Corporal , Hipertensão/etiologia , Obesidade/complicações , Adulto , Idoso , Feminino , Seguimentos , Humanos , Hipertensão/epidemiologia , Hipertensão/fisiopatologia , Incidência , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Obesidade/epidemiologia , Obesidade/fisiopatologia , Fatores de Risco , Fumar/efeitos adversos , Fumar/epidemiologia , Aumento de PesoRESUMO
Sacrolemmal vesicles were isolated from trout ventricles with a yield of 0.51 mg protein/g wet wt of a fraction enriched approximately 15-fold over the crude homogenate as estimated by K(+)-stimulated p-nitrophenylphosphatase (K(+)-pNPPase) activity. Although the K(+)-pNPPase specific activity compared favorably with that of the rat heart, there were some striking differences in the sodium dodecyl sulfate-polyacrylamide gel electrophoresis and specific phospholipid content (mumol/mg protein) of the sacrolemmal fractions between the two species. Two major sarcolemmal Ca2(+)-transport proteins were investigated, the Na(+)-Ca2+ exchanger and the dihydropyridine (DHP) receptor, a component of the voltage-dependent L-type Ca2+ channel. From the initial rates of Na(+)-dependent Ca2+ uptake, it was determined that the exchanger has an apparent Km for Ca2+ of 14 +/- 1 microM and a maximum velocity of 7.7 +/- 1.1 nmol.mg protein-1.s-1 at 21 degrees C. Experiments using the DHP ligand [3H] (+) PN 200-110 to characterize the equilibrium binding to the DHP receptor in the sarcolemmal fraction yielded a Kd of 0.08 nM and maximum binding sites of 3.06 +/- 0.49 pmol/mg protein. Given the smaller dimensions of the trout myocyte and the resultant higher sarcolemmal surface to cytosolic volume compared with the mammalian myocyte, these in vitro findings are consistent with the notion that Ca2+ transport across sarcolemma is a quantitatively important contributor of Ca2+ delivery to and removal from the contractile element.
Assuntos
Cálcio/metabolismo , Miocárdio/metabolismo , Salmonidae/metabolismo , Truta/metabolismo , Animais , Sítios de Ligação , Transporte Biológico , Proteínas de Transporte/metabolismo , Membrana Celular/metabolismo , Eletroforese em Gel de Poliacrilamida , Isradipino , Miocárdio/ultraestrutura , Oxidiazóis/metabolismo , Trocador de Sódio e CálcioRESUMO
A case-control study was performed in order to examine the relation of cigarette smoking and alcohol use to colorectal carcinoma in situ and cancer, separately. Study subjects consisted of 129 colorectal carcinoma in situ cases, 66 colorectal cancer cases, and 390 controls recruited from health check-up examinees in Tokyo from January 1991 to March 1993. Smoking status and alcohol habit were ascertained from a self-administered questionnaire. Both cumulative cigarette smoking and current smoking status were associated significantly with an increased risk of carcinoma in situ. A statistically nonsignificant increase in the risk of colorectal cancer was noted only among those with the heaviest exposure category of these measures of smoking. The cumulative exposure to cigarette smoking within recent 20 years was associated significantly with an increased risk of carcinoma in situ, whereas smoking until 20 years before the diagnosis was associated significantly with an increase of cancer risk. A significant and positive association was observed between cumulative alcohol drinking and colorectal cancer. These findings suggest that cigarette smoking may act as an initiator in colorectal carcinogenesis and also provide weak evidence that alcohol drinking is related to an increased risk of colorectal cancer.
Assuntos
Adenoma/epidemiologia , Consumo de Bebidas Alcoólicas/epidemiologia , Carcinoma in Situ/epidemiologia , Neoplasias Colorretais/epidemiologia , Fumar/epidemiologia , Adenoma/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Consumo de Bebidas Alcoólicas/efeitos adversos , Carcinoma in Situ/etiologia , Estudos de Casos e Controles , Neoplasias Colorretais/etiologia , Feminino , Humanos , Japão/epidemiologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Fumar/efeitos adversosRESUMO
Abnormalities in cardiac function have been extensively documented in experimental and clinical diabetes. These aberrations are well known to be exaggerated when hypertension and diabetes co-exist. The objective of the present study was to examine whether alterations in the activity of the myocardial Na+-Ca2+ exchanger (NCX) can account for the deleterious effects of diabetes and (or) hypertension on the heart. To this aim, the following experimental groups were studied: (i) control; (ii) diabetic; (iii) hypertensive; and (iv) hypertensive-diabetic. Wistar rats served as the control group (C) while Wistar rats injected with streptozotocin (STZ, 55 mg/kg) served as the diabetic (D) group. Spontaneously hypertensive (SH) rats were used as the hypertensive group (H) while SH rats injected with STZ served as the hypertensive-diabetic (HD) group. Sarcolemma was isolated from the ventricles of the C, D, H, and HD groups and NCX activity was examined using rapid quenching techniques to study initial rates over a [Ca2+]o range of 10-160 microM. The Vmax of NCX was lower in the D group when compared with the C group (D, 2.96 +/- 0.26 vs. C, 4.0 +/- 0.46 nmol x mgprot(-1) x s(-1), P < 0.05), however combined diabetes and hypertension (HD) did not affect the Vmax of NCX activity (HD, 3.84 +/- 0.88 vs. H, 3.59 +/- 0.24 nmol x mgprot(-1) x s(-1), P > 0.05). However, analysis of the Km values for Ca2+ indicated that both the D and HD groups exhibited a significantly lower Km when compared with their respective control groups (D, 42 +/- 4 vs. C, 56 +/- 4 microM, P < 0.05; HD, 33 +/- 7 vs. H, 51 +/- 8 microM, P < 0.05). Immunoblotting using polyclonal antibodies (against canine cardiac NCX) exhibited the typical banding of 160, 120, and 70 kDa. The 120 kDa band is believed to represent the native exchanger with its post-translational modifications. Examination of the blots revealed a lower intensity of the 120 kDa band in the D group when compared with the C group, however, no significant difference in the HD group was observed. We speculate that the lower Vmax in the D group may be due to a reduced concentration of exchanger protein in the membrane. The absence of this defect in the HD group may be a result of compensatory mechanisms to the overall hemodynamic overload, however, this remains to be determined. The increased affinity for Ca2+ in both the D and HD groups (determined by the lower Km values) is an interesting finding and may be due to changes in sarcolemmal lipid bilayer composition secondary to diabetes-induced hyperlipidemia.
Assuntos
Diabetes Mellitus Experimental/metabolismo , Hipertensão/metabolismo , Miocárdio/metabolismo , Trocador de Sódio e Cálcio/metabolismo , Animais , Peso Corporal , Masculino , Tamanho do Órgão , Ratos , Ratos Wistar , EstreptozocinaRESUMO
Fourteen sedentary young volunteers performed a maximal exercise test on a bicycle ergometer before, after and eight or nine weeks after 20 days bed rest. They were divided into four groups. They all went through 20 days bed rest; 5 females and 6 males as controls while 3 males performed mild pedaling supine exercise for 30 minutes twice a day. Three other males from the control group started a retraining programme after bed rest performing mild pedaling exercise in the sitting position for an hour a day, 3-4 days a week for eight weeks. VO2max was reduced after bed rest in all groups. In the control group the 6 males decreased VO2max from 2.82 +/- 0.09 1.min-1 before bed rest to 2.42 +/- 0.14 1.min-1 after. The female controls decreased from 2.55 +/- 0.24 1.min-1 to 2.22 +/- 0.23 1.min-1. The exercise regime performed by the three males during bed rest did not prevent a fall in VO2max in that group from 2.76 +/- 0.06 to 2.57 +/- 0.09 1.min-1. The three males who performed bicycle exercise in the recovery period did not attain higher recovery values at 8-9 weeks than the other males. However the 5 female controls did not recover their > 13% loss in VO2max after 8-9 weeks of recovery. Calculation of peak oxygen pulse from VO2max divided by heart rate indicated that these changes in VO2max were caused exclusively by a reduction in stroke volume of the heart, a finding supported by resting echocardiography of left ventricular end-diastolic diameter and stroke volume.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Repouso em Cama/efeitos adversos , Exercício Físico/fisiologia , Consumo de Oxigênio/fisiologia , Adulto , Teste de Esforço , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Caracteres Sexuais , Volume Sistólico/fisiologia , Decúbito Dorsal , Função Ventricular Esquerda/fisiologiaRESUMO
To evaluate the effects of inactivity on the cardiovascular system in normal subjects, left ventricular echocardiography and vascular ultrasound of the common carotid artery, abdominal aorta and femoral artery, and lower body negative pressure tests were performed in 14 healthy volunteers (mean age: 22 years) before and after 20 days of strict bed rest. Cardiac output was calculated from echocardiographic measurements and peripheral arterial flows by multiplying cross-sectional area of an artery by heart rate and time-velocity integral measured by pulsed Doppler ultrasound with angle correction. Systemic vascular resistance, lower body vascular resistance, leg vascular resistance and head vascular resistance were also calculated. After bed rest, heart rate increased (69 +/- 2 to 79 +/- 3 bpm), while left ventricular diastolic dimension (49 +/- 1 to 45 +/- 1 mm), systolic blood pressure (137 +/- 5 to 116 +/- 4 mmHg), cardiac output (6.2 +/- 0.3 to 5.4 +/- 0.3 1.min-1), abdominal aortic flow (4.1 +/- 0.4 to 3.1 +/- 0.3 1.min-1), femoral artery flow (0.66 +/- 0.07 to 0.33 +/- 0.04 1-min-1), and lower body negative pressure test tolerance time (750 +/- 71 to 582 +/- 48 s) decreased significantly (p < 0.05). However, common carotid artery flow (0.97 +/- 0.09 to 1.03 +/- 0.08 1.min-1) did not change. Although no significant changes in systemic vascular resistance, lower body vascular resistance or head vascular resistance were observed, leg vascular resistance increased significantly after 20 days of bed rest (6933 +/- 2905 to 13221 +/- 2606 dyn.s.cm-1) (p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)