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1.
To explore reasons for a high accumulation of Ca and P occurring in the coronary artery of Thai with aging, the authors investigated
age-related changes of elements in the coronary artery, ascending aorta near the heart, and cardiac valves in single individuals,
and the relationships in the elements between the coronary artery and either the ascending aorta or cardiac valves. After
an ordinary dissection by medical students at Chiang Mai University was finished, the anterior descending arteries of the
left coronary artery, ascending aortas, mitral valves, and aortic valves were resected from the subjects. The subjects consisted
of 17 men and 9 women, ranging in age from 46 to 76 yr. The element content was analyzed by inductively coupled plasma-atomic
emission spectrometry. The average content of Ca and P was the highest in the coronary artery and decreased in the order aortic
valve, ascending aorta, and mitral valve. The Ca, P, and Mg content increased in the coronary artery in the fifties and in
the ascending aorta, aortic valve, and mitral valve in the sixties. It should be noted that the accumulation of Ca, P, and
Mg occurred earlier in the coronary artery than in the ascending aorta, aortic valve, and mitral valve. It was found that
with respect to the Ca, P, Mg, and Na contents, the coronary artery correlated well with both the aortic valve and ascending
aorta, especially with the aortic valve, but it did not correlate with the mitral valves. This finding suggests that the accumulation
of Ca, P, Mg, and Na occurs in the coronary artery together with the aortic valve and ascending aorta, but not together with
the mitral valve. Because regarding the accumulation of Ca, P, and Mg, the ascending aorta and aortic valve are preceded by
the coronary artery, it is unlikely that the accumulation of Ca, P, and Mg spreads from the ascending aorta or aortic valve
to the coronary artery. 相似文献
2.
To elucidate compositional changes of arteries with aging, the authors previously investigated age-related changes of mineral
contents in the various arteries of Japanese and Japanese monkey. To examine whether there were differences between races
in regard to age-related changes of mineral contents and the relationships among element contents in the arteries, the authors
investigated the arteries of Thai. The subjects consisted of 13 men and 3 women, ranging in age from 39 to 84 yr. After the
ordinary dissection at Chiang Mai University was finished, abdominal aortas, common iliac, internal iliac, and external iliac
arteries were resected and the element contents were determined by inductively coupled plasma-atomic emission spectrometry.
The contents of calcium, phosphorus, and magnesium became the highest in the fifties in the abdominal aorta, common iliac,
and external iliac arteries, whereas the contents of calcium and magnesium became the highest in the sixties in the internal
iliac artery, and decreased thereafter. In regard to relationships among element contents, it was found that there were high
correlations between calcium and phosphorus contents, between calcium and magnesium contents, and between phosphorus and magnesium
in all of the abdominal aortas and three iliac arteries. The mass ratios of magnesium to calcium and phosphorus were each
similar in the abdominal aorta, common iliac, and internal iliac arteries, except for the external iliac artery, in which
it was slightly high. These revealed that as calcium and phosphorus increased in the arteries with aging, magnesium increased
in the arteries as well. The differences between the arteries of Thai and Japanese were discussed in the present article. 相似文献
4.
Summary Calcium and phosphorus were measured in the yolk and albumen of fertile pigeon (Columba livia) eggs incubated for 0–17 days, and in embryos and hatchlings. Shell provided most of the calcium for skeletal mineralization of the embryos, whereas phosphorus was derived from the yolk and albumen. Mobilization of calcium from the shell to the embryo commenced at approximately day 11 of incubation, accumulating both in the embryo and the yolk sac. There was 1.4 times more calcium in squab yolk sacs than that contained in newly laid egg yolks. The results suggest that whereas general patterns of calcium and phosphorus accumulation during embryogenesis in altricial birds closely resemble those of precocial birds, calcium mobilization from the shell begins later, proceeds at a slower rate and results in a less mineralized hatchling.CIDA/NSERC Visiting Research Associate
Permanent address: Department of Animal Science, University of Peradeniya, Peradeniya, Sri Lanka 相似文献
5.
To examine whether an accumulation of elements in the arteries with aging differs between human and animal, the authors investigated
the relationships among element contents in the arteries of the Japanese monkeys. The Japanese monkeys consisted of five males
and four females, ranging in age from 2 to 29 yr. The aorta, common and external iliac, femoral, common carotid, subclavian,
and axillary arteries were resected from the monkeys and element contents were determined by inductively coupled plasma-atomic
emission spectrometry. It was found that there were very high correlations between calcium and phosphorus contents, between
calcium and magnesium contents, and between phosphorus and magnesium contents in all of the monkey arteries. In addition,
significant correlations were found among the other element contents in some, but not all of the arteries. These results were
consistent with the foregoing findings of the human arteries. It is likely that magnesium forms compounds with phosphorus
or calcium in the monkey arteries. 相似文献
7.
BackgroundAlthough decision-making using the heart-team approach is apparently intuitive and has a class I recommendation in most recent guidelines, supportive data is still lacking. The current study aims to demonstrate the individualised clinical pathway for mitral valve disease patients and to evaluate the outcome of all patients referred to the dedicated mitral valve heart team. MethodsAll patients who were evaluated for mitral valve pathology with or without concomitant cardiac disease between 1 January 2016 and 31 December 2016 were prospectively followed and included. Patients were evaluated, and a treatment strategy was determined by the dedicated mitral valve heart team. ResultsOne hundred and fifty-eight patients were included; 67 patients were treated surgically (isolated and concomitant surgery), 20 by transcatheter interventions and 71 conservatively. Surgically treated patients had a higher 30-day mortality rate (4.4%), which decreased when specified to a dedicated surgeon (1.7%) and in primary, elective cases (0%). This was also observed for major adverse events within 30 days. Residual mitral regurgitation >grade 2 was more frequent in the catheter-based intervention group (23.5%) compared to the surgical group (4.8%). ConclusionIn conclusion, the implementation of a multidisciplinary heart team for mitral valve disease is a valuable approach for the selection of patients for different treatment modalities. Our research group will focus on a future comparative study using historical cohorts to prove the potential superiority of the dedicated multidisciplinary heart-team approach. 相似文献
9.
To examine whether there were differences between races in regard to age-related changes of mineral contents and the relationships
among element contents in the arteries, the authors investigated the coronary arteries of Thai and Japanese. The Thai subjects
consisted of 13 men and 3 women, ranging in age from 39 to 84 yr, whereas the Japanese subjects consisted of 17 men and 9
women, ranging in age from 55 to 92 yr. After the ordinary dissections at Chiang Mai University and Nara Medical University
were finished, the coronary arteries were resected and the element contents were determined by inductively coupled plasma-atomic
emission spectrometry. In the Thai, an accumulation of calcium and phosphorus began to occur in the forties and increased
markedly in the fifties, whereas in the Japanese, an accumulation of calcium and phosphorus began to occur in the seventies
and increased markedly in the nineties. The result revealed that an accumulation of calcium and phosphorus occurred earlier
in the Thai than in the Japanese. Regarding the relationships among element contents, extremely significant correlations were
found between calcium and phosphorus contents, between calcium and magnesium contents, and between phosphorus and magnesium
contents in both the coronary arteries of the Thai and the Japanese. As far as the coronary arteries with a very high accumulation
of calcium and phosphorus, the mass ratios of magnesium to calcium and phosphorus were lower in the coronary arteries of the
Thai in comparison with the Japanese. 相似文献
10.
To examine whether there were differences between races in regard to the relationships among element contents in the arteries,
the authors investigated the relationships among the average contents of calcium, phosphorus, sulfur, and magnesium in the
18 kinds of the Thai artery. After ordinary dissection by medical students at Chiang Mai University was finished, the thoracic
and abdominal aortas, ramifying site of the abdominal aorta into the common iliac arteries, coronary, common carotid, internal
thoracic, subclavian, axillary, brachial, radial, superior and inferior mesenteric, renal, common iliac, internal iliac, and
external iliac arteries were resected from the subjects who consisted of 12 men and 3 women, ranging in age from 39 to 84
yr. The femoral and posterior tibial arteries were resected from the subjects, consisting of 15 men and 5 women, ranging in
age from 25 to 88 yr. The element content of the arteries was analyzed by inductively coupled plasma-atomic emission spectrometry.
It was found that there were extremely significant direct correlations among the average contents of calcium, phosphorus,
and magnesium in the 18 kinds of the Thai artery, but no significant correlations were found between the average contents
of sulfur and elements, such as calcium, phosphorus, and magnesium. These results were in agreement with those of the Japanese
arteries. Therefore, it was suggested that there was no significant difference between the arteries of the Thai and the Japanese
in the relationships among calcium, phosphorus, sulfur, and magnesium. 相似文献
11.
Verapamil was administered 30 days to adult male rats in a dose of 2 mg/rat per day and the calcium ionophore A 23187 to another group in a dose of 10 micrograms/rat per day. After verapamil, the bone calcium and phosphorus concentration rose significantly compared with the control group, whereas after ionophore A 23187 the bone calcium concentration fell statistically significantly. 相似文献
13.
Alterations in mitral valve mechanics are classical indicators of valvular heart disease, such as mitral valve prolapse, mitral regurgitation, and mitral stenosis. Computational modeling is a powerful technique to quantify these alterations, to explore mitral valve physiology and pathology, and to classify the impact of novel treatment strategies. The selection of the appropriate constitutive model and the choice of its material parameters are paramount to the success of these models. However, the in vivo parameters values for these models are unknown. Here, we identify the in vivo material parameters for three common hyperelastic models for mitral valve tissue, an isotropic one and two anisotropic ones, using an inverse finite element approach. We demonstrate that the two anisotropic models provide an excellent fit to the in vivo data, with local displacement errors in the sub-millimeter range. In a complementary sensitivity analysis, we show that the identified parameter values are highly sensitive to prestrain, with some parameters varying up to four orders of magnitude. For the coupled anisotropic model, the stiffness varied from 119,021 kPa at 0 % prestrain via 36 kPa at 30 % prestrain to 9 kPa at 60 % prestrain. These results may, at least in part, explain the discrepancy between previously reported ex vivo and in vivo measurements of mitral leaflet stiffness. We believe that our study provides valuable guidelines for modeling mitral valve mechanics, selecting appropriate constitutive models, and choosing physiologically meaningful parameter values. Future studies will be necessary to experimentally and computationally investigate prestrain, to verify its existence, to quantify its magnitude, and to clarify its role in mitral valve mechanics. 相似文献
16.
Adult male rats were given prednisolone (Urbason solubile = 6-methyl-prednisolone) in doses of 4 mg/100 g body weight for 10, 20 or 30 days and its effect on the calcium, phosphorus and magnesium content of their femurs was studied. At all the given intervals a statistically significant decrease in the magnesium content of the bone was found; the calcium content was significantly reduced only in the first phase of the experiment (at 10 days). 相似文献
17.
An incidence of cardiac arrhythmias was evaluated in 119 patients with mitral valve prolapse. The disease was made basing on the results of clinical symptoms, echo-, angio- and phonocardiography. Electrocardiograms were recorded from the standard 12 lead and Holter technique for 24 hours in each patient to assess present arrhythmias. It was found that the most frequent cardiac arrhythmias accompanying mitral valve prolapse are ventricular extrasystolic contractions of Lown's class 1a and 1b. Only examination of strictly selected groups of patients (age groups with or without co-existing mitral valve insufficiency for adequate period of time) will facilitate precise evaluation of an incidence of different cardiac arrhythmias accompanying the underlying disease. 相似文献
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