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71.
Dr. Töres Theorell M.D. Dr. Richard H. Rahe MC USNR 《Behavioral medicine (Washington, D.C.)》2013,39(3):18-24
Abstract Thirty-six men and women who experienced a documented myocardial infarction, half of whom ultimately died from their disease and half of whom survived over a six-year period, provided longitudinal recent life changes and ballistocardiographic data. The 18 patients who died from their coronary disease indicated a significant buildup in life changes which peaked approximately one year prior to death; their serial ballistocardiograms indicated a significant buildup in average force of contraction which was seen to peak approximately six months prior to death. The 18 post-infarction patients who survived the six-year follow-up showed neither a buildup in life change nor a buildup in the ballistocardiographic index of cardiac contraction force. These findings of a life change peak preceding ballistocardiographic evidence of an “overworked” heart are discussed in terms of their possible medical and psychophysiological significances. 相似文献
72.
AMJ van Wegberg RAF Evers JGM Burgerhof E van Dam M.R. Heiner-Fokkema MCH Janssen MC de Vries FJ van Spronsen 《Molecular genetics and metabolism》2021,132(1):49-55
BackgroundIn patients with phenylketonuria, stability of blood phenylalanine and tyrosine concentrations might influence brain chemistry and therefore patient outcome. This study prospectively investigated the effects of tetrahydrobiopterin (BH4), as a chaperone of phenylalanine hydroxylase on diurnal and day-to-day variations of blood phenylalanine and tyrosine concentrations.MethodsBlood phenylalanine and tyrosine were measured in dried blood spots (DBS) four times daily for 2 days (fasting, before lunch, before dinner, evening) and once daily (fasting) for 6 days in a randomized cross-over design with a period with BH4 and a period without BH4. The sequence was randomized. Eleven proven BH4 responsive PKU patients participated, 5 of them used protein substitutes during BH4 treatment. Natural protein intake and protein substitute dosing was adjusted during the period without BH4 in order to keep DBS phenylalanine levels within target range. Patients filled out a 3-day food diary during both study periods. Variations of DBS phenylalanine and Tyr were expressed in standard deviations (SD) and coefficient of variation (CV).ResultsBH4 treatment did not significantly influence day-to-day phenylalanine and tyrosine variations nor diurnal phenylalanine variations, but decreased diurnal tyrosine variations (median SD 17.6 μmol/l, median CV 21.3%, p = 0.01) compared to diet only (median SD 34.2 μmol/l, median CV 43.2%). Consequently, during BH4 treatment diurnal phenylalanine/tyrosine ratio variation was smaller, while fasting tyrosine levels tended to be higher.ConclusionBH4 did not impact phenylalanine variation but decreased diurnal tyrosine and phenylalanine/tyrosine ratio variations, possibly explained by less use of protein substitute and increased tyrosine synthesis. 相似文献
73.
Merot J Charpentier F Poirier JM Coutris G Weissenburger J 《Cardiovascular research》1999,44(2):303-314
OBJECTIVE: The present study was designed to examine the effects of chronic amiodarone on the different ventricular cell subtypes in situ and to evaluate its interactions with sotalol. METHODS: Three groups of dogs were studied. Group I (n = 8) received no treatment. Group II (n = 7) and group III (n = 8) received, respectively, 100 and 200 mg amiodarone orally twice a day for 6 weeks to 8 months. In vivo studies were performed under halothane anesthesia 14 h after the last administration of amiodarone. Three leads ECG, femoral blood pressure and left ventricular intramural monophasic action potentials (MAP) were continuously recorded. Bradycardia was obtained by clamping the sinus node and beta-blockade and the heart was driven by atrial pacing. Three weeks before the in vivo experiments, the cellular electrophysiologic properties of right ventricular tissues obtained by cardiac biopsy in six treated and six control dogs were studied with standard microelectrodes. RESULTS: Amiodarone produced a dose-dependent decrease in plasma levels of triiodothyronine (T3; 5.9 +/- 0.4 pM in control dogs, 3.1 +/- 0.2 pM in group III, P < 0.001) without affecting thyroxine (T4). Under anesthesia, the QT interval was 14% larger in group III compared to group I at a paced cycle length (PCL) of 1500 ms (P < 0.05). This is consistent with the 10% increase in endocardial MAP duration in group III at the same PCL (P < 0.05). There was no significant increase in transmural dispersion of MAP duration. In group I, sotalol induced a significant reverse use-dependent increase in MAP duration. This effect was reduced in group II and completely suppressed in group III. Amiodarone prevented the sotalol-induced increase in transmural dispersion of ventricular repolarization which was 69 +/- 12 ms in untreated dogs, 41 +/- 8 ms in group II (P < 0.05) and 34 +/- 8 ms (P < 0.05) in group III at PCL = 1500 ms. Amiodarone also prevented the sotalol-induced ventricular tachyarrhythmias. In vitro, the action potential duration was longer in amiodarone-treated dogs that in control ones (208 +/- 5 ms versus 188 +/- 9 ms at PCL = 1000 ms, P < 0.05). The sotalol-induced prolongation of repolarization was reduced in amiodarone-treated dogs. CONCLUSION: Chronic treatment of dogs with amiodarone induced a moderate prolongation of the QT interval and MAP duration without affecting transmural dispersion of repolarization and inhibited the effects of acute sotalol, including the prolongation of repolarization, the increase in transmural dispersion of repolarization and the induction of arrhythmias. 相似文献
74.
Randle C. Johnson M.D. Major USAF MC Michael H. Bleshman M.D. James W. DeFord M.D. 《Diseases of the colon and rectum》1978,21(7):510-513
Summary We have presented an unusual case of benign lymphoid hyperplasia, which manifested as a cecal deformity in a 15-year-old boy.
The clinical manifestation may have been related to partial occlusion of the appendiceal orifice. In future cases of benign
lymphoid hyperplasia, colonoscopy may be diagnostic, and if it is used for continuing observation, may avert unnecessary surgical
procedures in children and young adults. 相似文献
75.
LTC Lawrence F. Johnson MC USA LTC Tom R. Demeester MC USA MAJ Roger C. Haggitt MC USA 《Digestive diseases and sciences》1978,23(6):498-509
Exposure of the distal esophageal mucosa to acid gastric juice was quantitated by 24-hr pH monitoring in 100 individuals and was correlated with morphologic data derived from esophageal biopsies. The degree of acid exposure to the distal esophagus correlated directly with increases in both relative and absolute length of the subepithelial papillae and to relative basal zone hyperplasia. Both papillary length and basal zone hyperplasia decreased after antireflux surgery had reduced acid exposure to normal. Reflux in the recumbent position resulted in prolonged exposure of the mucosa to acid because of poor acid clearing from the esophagus. This caused longer papillae than did upright reflux, where there were more frequent reflux episodes, but with rapid acid clearance. The presence of a hiatal hernia was associated with longer papilae, lower DES pressure, increased reflux frequency, and prolonged recumbent acid clearance. Twenty-four hour pH monitoring correlated better with papillary length than did symptoms or other clinical measures of gastroesophageal reflux. 相似文献
76.
77.
Platelet alpha-granule and plasma membrane share two new components: CD9 and PECAM-1 总被引:1,自引:2,他引:1
CD9 (p24) and PECAM1 (CD31) antigens are well-defined components of the platelet plasma membrane. Both are integral glycoproteins (GPs) implicated in the adhesive and aggregative properties of human platelets. In the present report, we have investigated their subcellular localization using immunoelectron microscopy. The monospecificity of the two polyclonal antibodies used was confirmed by immunoblotting. On normal resting platelets, immunolabeling for CD9 and PECAM1 was found lining the plasma membrane and the luminal face of the open canalicular system. Some labeling was also consistently found on the alpha-granule limiting membrane. This was confirmed by double labeling experiments in which fibrinogen and von Willebrand factor (vWF) were used as alpha-granule markers. CD9 and PECAM-1 were found lining the membrane of the same granules that contained fibrinogen and vWF in their matrix. CD9 and PECAM-1 thus appear to have an intracellular distribution identical to GPIIb-IIIa, a major aggregation platelet receptor. To rule out a cross-reactivity of the two polyclonal antibodies with GPIIb/IIIa, we studied PECAM1 and CD9 expression on the platelets from a patient with type I Glanzmann's thrombasthenia whose platelets are devoid of GPIIb/IIIa. The same pattern of labeling was observed for both antigens as for normal platelets. Normal platelets were further observed after stimulation by agonists that either fail to induce (ADP) or induce granule secretion (thrombin). After treatment with ADP, platelets changed shape and centralized their granules; the plasma membrane immunolabeling remained unchanged; and gold particles were still found decorating the periphery of the centralized alpha- granules. After thrombin treatment, alpha-granules fused with the platelet membrane and secretion occurred. A significant increase of labeling was then observed on the platelet surface. From these results we conclude that the alpha-granule membrane contains two additional receptors in common with the plasma membrane. This suggests that alpha- granule membrane receptors may originate from a dual mechanism: direct targeting from the Golgi complex in megakaryocytes (for alpha-granule- specific receptors such as P-selectin) or by endocytosis from the plasma membrane (for proteins distributed in the two compartments). 相似文献
78.
Analysis of exercise-induced R wave amplitude changes in detection of coronary artery disease in asymptomatic men with left bundle branch block 总被引:1,自引:0,他引:1
Gregory S. Uhl USAF MC Major J.Andrew C. Hopkirk MRCP RAF Squadron Leader 《The American journal of cardiology》1979,44(7):1247-1250
The exercise electrocardiograms of 44 asymptomatic men with acquired left bundle branch block were analyzed for changes in R wave amplitude. Results were correlated with findings on selective coronary angiography. There were two subgroups: 7 men with significant angiographic coronary artery disease (Group I) and 37 with normal coronary angiograms (Group II). Exercise induced an increase in R wave amplitude in all seven men with coronary artery disease but in only 10 of the 37 men without significant coronary artery disease. This criterion thus had a sensitivity of 100 percent but a poor specificity of 73 percent, a predictive value of 41 percent and an accuracy rate of 77 percent for the diagnosis of coronary artery disease. The greater the increase in R wave amplitude the greater was the likelihood of some degree of left ventricular dysfunction as measured by wall motion abnormalities and elevated left ventricular end-diastolic pressure. The increase in R wave amplitude with exercise appears to be a sensitive test in identifying coronary artery disease in asymptomatic men with acquired left bundle branch block. 相似文献
79.
80.
Poliakova N Després JP Bergeron J Alméras N Tremblay A Poirier P 《Metabolism: clinical and experimental》2012,61(9):1270-1279
Heart rate variability (HRV) is affected by age, hyperglycemia and accumulation of body fat. This study compares the predictive value of four measurements of adiposity/obesity on HRV and investigates the specific role of age, metabolic contributors and degree/distribution of fat in HRV alterations. The sample consisted of 97 non-diabetic and non-medicated men with features of the metabolic syndrome (50 ± 8 years of age, body mass index [BMI] 31 ± 3 kg/m2, waist circumference [WC] 107 ± 9 cm, triglycerides 2.3 ± 0.7 mmol/L, fasting glucose 6.0 ± 0.5 mmol/L, insulin 156 ± 71 pmol/L; mean ± SD). WC, BMI, percent body fat (% fat, from dual energy X-ray absorptiometry) and visceral adipose tissue volume (VAT, from computed tomography) were used as measures of adiposity/obesity. HRV measures were obtained from 24-h, day- and night-time segments of Holter recordings. BMI presented no independent association with HRV. Percentage fat was the strongest obesity index to be associated with HRV: 24-h pNN50, rMSSD, HF and daytime pNN50, rMSSD, HF and LF (?0.27 ≤ std β ≤ ?0.20, P < .05). VAT was associated with 24-h SDNN, LF (std β = ?0.25 and ?0.20, P < .05, respectively) and daytime SDNN (std β = ?0.24, P < .05) while WC was associated with nighttime SDNN and SDANN (std β = 0.22 and 0.32, P < .05). In addition, age, fasting glucose, 2-h oral glucose tolerance test and triglycerides presented independent association with HRV. Adiposity/obesity measurements seem to be differently associated with HRV. An approach considering the combination of age, obesity and glucose metabolism factors could be helpful in the global cardiovascular risk management in abdominally obese men. 相似文献