(Circulation. 1997;96:556-561.)
© 1997 American Heart Association, Inc.
Articles |
Abnormal Epinephrine Release in Young Adults With High Personal and High Parental Blood Pressures
From the Medical Research Council Blood Pressure Unit (S.B.H., R.F., G.C.I., A.F.L.) and the Biochemistry Department (M.H.D.), Western Infirmary, Glasgow; the Department of Pathological Biochemistry (G.H.B.), Royal Infirmary, Glasgow; Mount Vernon Hospital (C.J.W.F.), Northwood, Middlesex; and the Department of General Practice (G.C.M.W.), University of Glasgow, UK.
Correspondence to Professor Stephen B. Harrap, Department of Physiology, University of Melbourne, Parkville, Victoria 3052 Australia. E-mail s.harrap{at}physiology.unimelb.edu.au
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Abstract |
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Background Increased activity of the sympathetic nervous system has been proposed as a cause of high blood pressure (BP) and may be related to diet and body weight. To determine the role of these factors in predisposition to high BP, we studied 100 young adults with high or low BP from families in which both parents had either high or low BP.
Methods and Results Plasma catecholamine, glucose, and insulin levels were measured before and after an oral glucose load. There was a significant correlation between fasting plasma norepinephrine and mean arterial pressure (P=.001). Subjects with high BP, irrespective of parental BP, were heavier (P=.003) and fatter (P=.002) and had a greater rise in plasma insulin (P=.003) following glucose than those with low BP. Offspring with high BP whose parents also had high BP showed an unexpected rise in plasma epinephrine (P=.004) following glucose. This adrenal medullary response was not the result of high parental or high personal BP alone as it was not seen in offspring with low BP whose parents had high BP or in offspring with high BP whose parents had low BP.
Conclusions Irrespective of family history, high BP is associated with increased body weight and hyperinsulinemia and reflects personal environment and behavior. However, abnormal epinephrine release is characteristic of the combination of genetic, environmental, and behavioral factors that is associated with high personal BP and a familial predisposition to high BP.
Key Words: genetics • epidemiology • catecholamines • insulin • hormones • blood pressure
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Introduction |
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High BP is associated with abnormalities of the sympathetic nervous system1 2 and insulin metabolism.3 4 Similar findings are reported in young people predisposed to high BP. Familial factors are important, and increased cardiovascular responses to mental stress5 and catecholamine responses to physical stress6 have been reported in subjects with a history of parental hypertension. Abnormal insulin metabolism, including hyperinsulinemia and/or insulin resistance, is also evident in the offspring of hypertensive parents.7 8 9 However, the relationship between familial patterns of sympathetic activity and insulin metabolism is not well understood.
In general, the metabolic effects of insulin and the sympathetic nervous system are opposite and part of normal homeostasis. For example, the hypoglycemic effects of insulin are antagonized by the sympathetically mediated release of EPI from the adrenal medulla. However, insulin may stimulate central activation of sympathetic nerves.10 In the long term, high energy intake and BMI may result in increased insulin levels,11 increased activity of the sympathetic nervous system,12 and increased BP.13 The nature of these links is not clear and may involve interactions between personal environment or behavior and genetic predisposition.14
This study aimed to examine the relationship between body composition and the responses of the sympathetic nervous system, adrenal medulla, and insulin to glucose ingestion in individuals predisposed to high BP. Predisposition was defined on the basis of both personal and parental BP levels. We used the four-corners method15 16 17 to select groups of healthy young adults from the general population with high or low personal and high or low parental BPs. This approach provides a method for finding correlates that are not apparent in studies based on personal or parental pressures alone because it is possible to compare and contrast correlates of raised BP in subjects with and without familial predisposition. This study was designed to examine in healthy young adults with high BP whether body size and composition, sympathetic nervous activity, or the physiological response to glucose depends on familial predisposition.
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Methods |
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Subject Selection
The four-corners design relies on BP data from both parents and children and has been described in detail.15 16 17 In brief, BPs were measured in 864 young adults, aged 16 to 24 years, from 603 families. Their parents had undergone BP measurements 8 years before as part of the screening phase of the Medical Research Council Mild Hypertension Trial. Individual BPs were adjusted for the effects of age, sex, and use of the oral contraceptive pill. The BPs of subjects being treated for hypertension were adjusted to place them in the top 5% of the distribution. Maternal and paternal BPs were combined to provide a single parental BP for each offspring.
The personal BPs of the offspring were plotted against their combined
parental pressures in a scatter diagram (Fig 1
). High
pressures were considered to be those in approximately the top 30% of
personal or parental distributions. Low pressures were those in the
bottom 30% of the distributions. These relatively broad
epidemiological definitions were chosen to identify differences
associated with contrasts in BP within the general population rather
than with differences between normotensive subjects and patients with
clinical hypertension. The divisions resulted in four corners, ie,
offspring with high personal and low parental pressures, high personal
and high parental pressures, low personal and low parental pressures,
and low personal and high parental pressures. For this study we
recruited 
25 offspring from each group.
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Clinical Protocol
Subjects were admitted to the hospital on their normal diet, and
written informed consent was obtained from all volunteers. To minimize
potential bias, the BP categorizations of the parents and offspring
were not revealed to either the participants or the clinical
investigators. The studies were approved by the Western Infirmary
ethics committee.
Measurements were obtained of participants' height, weight, armspan, waist and hip circumferences, and skinfold thicknesses in the triceps, biceps, subscapular, and suprailiac regions. Body fat as a percentage of body weight was calculated from skinfold measurements.18 Total body fat was subtracted from body weight to calculate lean body mass.
At 7 AM, after an overnight fast that began at 9 PM, intravenous cannulae were inserted into the subjects' right and left cubital veins. A BP cuff was attached to the right arm, and BP and PR were measured automatically by a Copal UA251 autoinflation digital sphygmomanometer (Takeda Medical Corp) while subjects remained semisupine in bed. Three readings were taken every half hour for 2 hours and averaged at each time point to calculate the SBP, DBP, and PR.
Blood samples were taken at 8:30 AM for estimation of glucose, insulin, NE, EPI, dopamine, glycosylated hemoglobin, and fructosamine levels and a lipid profile by methods used previously.12 All subjects then drank 75 g of glucose in water. Blood was taken every half hour for 2 hours for measurements of glucose, insulin, and catecholamine levels. Cortisol and aldosterone were measured 1 hour after glucose ingestion.
Statistical Analysis
The effects of categorization according to parental and personal
BPs were analyzed by using a 2x2 factorial ANOVA design with
one factor being personal BP (high or low) and the other parental BP
(high or low). Characteristics that were dependent on particular
combinations of personal and parental BPs were identified in the ANOVA
as those associated with a significant statistic for interaction
between the two factors. Nonparametric correlation
analysis was used to calculate Spearman rank correlation
coefficients to examine relationships between variables in the
combined group of 100 subjects. To detect and control for effects
arising as a result of categorization according to personal and
parental BPs in the combined group, we used multiple regression
analysis. Pressure categories were entered into the regression
models as dummy variables (low=0, high=1). To control for any
sex-related differences in ANOVA and regression analyses,
gender was also entered as a dummy variable (female=0, male=1). For
variables measured several times, a repeated-measures ANOVA was
used.19 The 
2 test was used to
compare sex distribution and the use of the oral contraceptive pill
between groups. In view of the number of comparisons, we accepted
statistical significance as P<.005.
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Results |
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Baseline Characteristics: Hemodynamic and Anthropometric Variables
The four offspring groups comprised approximately equal numbers of individuals of similar average age (Table 1
). There were
no significant differences in the male/female ratio
(2 =2.31, df=3, P=.51) or
the use of the oral contraceptive pill (2 =6.35,
df=3, P=.10).
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Mean arterial pressure was significantly different between
the high and low groups (Table 1
), reflecting the original
categorization made 3 years previously. The persistence of these
differences with time indicates tracking of pressures and the
robustness of the original classification. PR was higher in offspring
with high personal pressures, and within this group, PR was higher in
offspring whose parental pressures were also high.
Body weight, BMI, and body fat were significantly greater in offspring
with high BPs irrespective of parental BPs (Table 2).
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Baseline Characteristics: Biochemical Variables
Fasting plasma NE was higher in those with high personal BPs
(Table 3) and correlated with mean arterial
pressure (r=.343, P=.001). In offspring whose
parents had high BP, plasma EPI was significantly higher
(P=.01) in those with high as opposed to low personal BPs.
No significant differences were seen between groups in fasting plasma
dopamine, nor were there any significant differences between the groups
in basal plasma glucose or insulin levels (Table 3). Indices of
time-averaged glycemia:fructosamine and glycosylated hemoglobin were
also similar between groups (data not shown). Lipid profiles (total,
HDL, LDL, and VLDL cholesterol and
triglycerides) were the same in each group (data not shown)
and were not associated with BP.
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Changes After Glucose
The hemodynamic response to glucose (Fig 2) comprised significant (P<.0001) increases
in PR and SBP and reductions in DBP. There were no differences in these
responses according to parental or personal BP groups. In the
subsequent period both SBP and DBP returned toward fasting values (Fig 2).
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There were significant (P<.0001) rises in plasma glucose
and insulin (Fig 3) 30 minutes after glucose.
Subsequently, subjects with high BPs had higher glucose and plasma
insulin levels (P=.008) than subjects with low BPs
irrespective of parental BPs. There was also a significant rise in
plasma NE 30 minutes after glucose in all groups (P<.0001),
but changes in plasma EPI were not uniform. Three groups showed no
change or a slight fall in plasma EPI 30 minutes after glucose (Fig 4) (P=.507). In contrast, subjects with both
high personal and high parental BPs showed a significant increase in
EPI (P<.004).
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Plasma dopamine levels rose significantly in all groups 30
minutes after glucose (data not shown). In the subsequent period,
plasma EPI fell slightly and nonsignificantly in all groups while
plasma NE levels remained relatively stable throughout the postglucose
period (Fig 4).
Influence of BMI
Because differences in BMI per se may influence insulin levels, we
performed two analyses of the insulin response to glucose,
taking BMI into account. First, BMI was entered as a covariate in the
ANOVA to correct for the association between BMI and insulin for the
entire sample. Second, insulin levels were corrected for individual
BMIs before being entered into the ANOVA. Neither approach showed a
significant relationship between high BP and insulin adjusted for BMI.
In contrast, the rise in plasma EPI in those with high personal and parental BPs remained statistically significant after adjustment for BMI.
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Discussion |
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TopAbstractIntroductionMethodsResultsDiscussionReferences |
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Studies of young people predisposed to high BP aim to identify physiological characteristics that may explain population variation in BP or precede the later development of clinical hypertension. Predisposition can be defined in two ways. High personal BPs predispose because of the tracking phenomenon. High parental BPs predispose because of genetic and/or shared behavioral or environmental factors within families. The physiological mechanisms underlying tracking and familial predisposition may differ and possibly interact. In this study we have identified phenotypes that associate with high personal BP irrespective of familial predisposition and a phenotype that is apparent only when high personal and parental BPs coincide.
In young adults with high BP, only those with high parental pressures showed a significant rise in plasma EPI in response to glucose ingestion. This phenotype is contrary to expectations, as EPI is normally released in response to insulin-induced hypoglycemia, and plasma EPI usually falls slightly during hyperglycemia.20 21 22 The physiological explanation for this unusual response is not obvious from these studies.
EPI is usually released in response to sympathetic stimulation of the adrenal medulla. Acetylcholine release by preganglionic nerves causes adrenal medullary chromaffin cells to secrete EPI. In our study, glucose ingestion and hyperinsulinemia resulted in stimulation of the sympathetic nerves20 23 24 as mirrored by increased PR and plasma NE. The magnitude of the generalized sympathetic response was not augmented in the subjects showing a rise in plasma EPI levels. Thus, higher EPI suggests a process involving the adrenal medulla specifically. Such a phenotype may be the result of greater regional sympathetic nerve traffic to the adrenal medulla or greater sensitivity of the adrenal medulla to sympathetic stimulation.25
The enzyme phenylethanolamine N-methyltransferase converts NE to EPI in the adrenal medullary chromaffin cells. The basal activity of this enzyme is modulated by the high levels of cortisol in blood flowing from the adrenal cortex.26 Therefore, increased adrenal cortical activity could enhance EPI production, storage, and release. The plasma cortisol levels obtained 30 minutes after glucose ingestion (9:30 AM) were not significantly higher in the group showing the exaggerated EPI release. However, we have reported16 that afternoon cortisol levels are significantly higher in these subjects, suggesting a loss of the normal diurnal fall in afternoon cortisol. These higher average cortisol levels may induce phenylethanolamine N-methyltransferase activity and contribute to the abnormal EPI release.
The EPI response to glucose is not a consequence of high personal BP alone as it was not found in offspring with high personal but low parental BPs. Dependence on parental BP suggests the influence of familial factors associated with high BP. However, high parental BP alone is not a sufficient explanation for EPI release, as it was not seen when offspring had high parental but low personal BPs. Therefore, the phenotype depends on the combination of individual and familial factors. This suggests that individual environment or lifestyle may interact with the genetic or environmental factors that characterize families in which both parents have high BP.
High personal BP was also associated with increased body fat and plasma NE levels and hyperinsulinemia. Similar observations have been made by others, and their possible interrelationships have been discussed.13 14 27 28 However, our study reveals for the first time that these phenotypes are independent of familial predisposition as they were observed when parental BPs were either high or low. The association between high personal BP and increased BMI and insulin and NE concentrations could be explained by the influence of individual environment or lifestyle. For example, high dietary energy intake or low energy expenditure through a sedentary lifestyle might cause increased body fat, leading to elevated plasma insulin and NE levels and BP.
Clearly, there is a potentially synergistic interaction between personal behavior and familial predisposition. If eating stimulates the release of EPI in genetically predisposed subjects, then larger or more frequent meals may augment the adrenal medullary response as well as contribute to increased body fat. Other stimulants of the sympathetic nervous system such as smoking or sex may also augment the release of EPI. Such intermittent increases may be more important in physiological terms than prolonged increases in EPI, which can lead to receptor desensitization.29
Direct actions of EPI may contribute to the development or sequelae of
hypertension. Through the ß-adrenergic receptors, EPI results in
inotropic and chronotropic stimulation of the heart and renin release.
Stimulation of the 
1-adrenergic receptors contracts the
vasculature and may have trophic effects on
cardiovascular muscle cells. EPI also has agonist
effects on the 2-adrenergic receptors, which are
numerous in organs relevant to long-term BP control such as the central
nervous system and the kidneys, where the 2-adrenergic
receptors mediate effects on neural vasomotor control and sodium
resorption, respectively.30
This study is unique in that it is based on families selected
from the general population and definitions of familial predisposition
based on BP measurements in two generations. The participants in this
study are a random subsample of offspring in the four corners who
together comprise 55% of the total population. The results bear on why
large numbers of people have BPs above and below the mean, rather than
why a few people have values in the tail of the distribution (eg,
patients with clinical hypertension). The abnormal adrenal medullary
function that occurs with the combination of high personal and parental
BPs exists in 14% of our population. This group comprises only 37%
of all offspring with high BP and 46% of all offspring from families
with high parental BPs. Studies based only on the presence or absence
of a "positive family history of hypertension" without reference
to personal BPs are unlikely to identify such phenotypes
because of a dilution effect. The adrenal medullary phenotype
would not have been identified in our study if we had selected on the
basis of high personal BP or high parental BP alone. Our study has also
shown that certain correlates of high BP, such as increased body
weight, transcend familial predisposition and are likely, therefore, to
have environmental or behavioral explanations. Such information from
young adults before the development of clinical hypertension may be
relevant to the development and targeting of prevention and treatment
strategies.
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Selected Abbreviations and Acronyms |
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Acknowledgments |
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This study was funded by the British Heart Foundation. Professor Harrap was supported as a Neil Hamilton Fairley Travelling Fellow of the National Health and Medical Research Council of Australia. We thank Drs D.W. Holton and H.V. Edwards of the Ladywell Medical Centre, Edinburgh, UK, for their valuable cooperation.
Received August 20, 1996; revision received February 3, 1997; accepted February 11, 1997.
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References |
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TopAbstractIntroductionMethodsResultsDiscussionReferences |
|---|
1. Goldstein DS. Plasma catecholamines and essential hypertension: an analytical review. Hypertension. 1983;5:86-89.
2. Esler M, Jennings G, Lambert G. Noradrenaline release and the pathophysiology of primary human hypertension. Am J Hypertens. 1989;2(suppl):140s-146s.
3. Welborn TA, Breckenridge A, Rubinstein A, Dollery CT, Russell Fraser T. Serum insulin in essential hypertension and peripheral vascular disease. Lancet. 1966;1:1336-1337.[Medline] [Order article via Infotrieve]
4. Ferrannini E, Buzzigoli G, Bonadonna R, Giorico MA, Oleggini M, Graziadei L, Pedrinelli, Brandi L, Bevilacqua S. Insulin resistance in essential hypertension. N Engl J Med. 1987;317:350-357.[Abstract]
5.
Falkner B, Onesti G, Angelakos ET, Fernandes M,
Langman C. Cardiovascular response to mental
stress in normal adolescents with hypertensive parents.
Hypertension. 1979;1:23-30.
6. Bachmann AW, Ballantine DM, Gordon RD. Effect of family history of hypertension on the blood pressure and catecholamine responses to 6 hour adrenaline infusion. Clin Exp Pharmacol Physiol. 1993;20:395-398.[Medline] [Order article via Infotrieve]
7. Facchini F, Chen YDI, Clinkingbeard C, Jeppesen J, Reaven GM. Insulin resistance, hyperinsulinemia and dyslipidemia in nonobese individuals with a family history of hypertension. Am J Hypertens. 1992;5:694-699.[Medline] [Order article via Infotrieve]
8. Allemann Y, Horber FF, Colombo M, Ferrari P, Shaw S, Jeager P, Weidemann P. Insulin sensitivity and body fat distribution in normotensive offspring of hypertensive parents. Lancet. 1993;341:327-331.[Medline] [Order article via Infotrieve]
9. Beatty OL, Harper R, Sheridan B, Atkinson AB, Bell PM. Insulin resistance in offspring of hypertensive parents. BMJ. 1993;307:92-96.
10. Rowe JW, Young JB, Minaker KL, Stevens AL, Pallotta J, Landsberg L. Effect of insulin and glucose infusions on sympathetic nervous activity in normal man. Diabetes. 1981;30:219-225.[Medline] [Order article via Infotrieve]
11. Grey N, Kipnis DM. Effect of diet composition on the hyperinsulinemia of obesity. N Engl J Med. 1971;285:827-831.
12. Tuck ML. Obesity, the sympathetic nervous system and essential hypertension. Hypertension. 1992;19(suppl I):I-67-I-77.
13.
Stallones L, Mueller WH, Christensen BL. Blood
pressure, fatness, and fat patterning among USA adolescents from two
ethnic groups. Hypertension. 1982;4:483-486.
14.
Wallin BG, Kunimoto MM, Sellgren J. Possible
genetic influence on the strength of human muscle nerve sympathetic
activity at rest. Hypertension. 1993;22:282-284.
15. Watt G. Design and interpretation of studies comparing individuals with and without a family history of high blood pressure. J Hypertens. 1986;4:1-7.[Medline] [Order article via Infotrieve]
16. Watt GCM, Harrap SB, Foy CJW, Holton DW, Edwards HE, Davidson HR, Connor JM, Lever AF, Fraser R. Abnormalities of glucocorticoid metabolism and the renin-angiotensin system: a four corners approach to the identification of genetic determinants of blood pressure. J Hypertens. 1992;10:473-482.[Medline] [Order article via Infotrieve]
17. Watt GCM, Foy CJW, Holton DW, Edwards HE. Prediction of high blood pressure in young people: the limited usefulness of parental blood pressure data. J Hypertens. 1991;9:55-58.[Medline] [Order article via Infotrieve]
18. Durnin JGVA, Womersley J. Body fat assessed from total body density and its estimation from skinfold thickness: measurements on 481 men and women aged from 16 to 72 years. Br J Nutr. 1974;32:77-97.[Medline] [Order article via Infotrieve]
19. SPSS Advanced Statistics User's Guide. Chicago, Ill: MJ Norusis/SPSS Inc; 1990:120-149.
20. Heseltine D, Potter JF, Hartley G, Macdonald IA, James OFW. Blood pressure, heart rate and neuroendocrine responses to a high carbohydrate and a high fat meal in healthy young subjects. Clin Sci. 1990;79:517-522.[Medline] [Order article via Infotrieve]
21. Berne C, Fagius J, Niklason F. Sympathetic response to oral carbohydrate administration: evidence from microelectrode nerve recordings. J Clin Invest. 1989;84:1403-1409.
22.
Sidery MB, Macdonald IA, Cowley AJ, Fullwood LJ.
Cardiovascular responses to high-fat and
high-carbohydrate meals in young subjects. Am J
Physiol. 1991;261:H1430-H1436.
23. Tse T, Clutter WE, Shah SD, Miller JP, Cryer PE. Neuroendocrine responses to glucose ingestion in man: specificity, temporal relationships and quantitative aspects. J Clin Invest. 1983;72:270-277.
24. Cox HS, Kaye DM, Thompson JM, Turner AG, Jennings GL, Itsiopoulos C, Esler M. Regional sympathetic nervous activation after a large meal in humans. Clin Sci. 1995;89:145-154.[Medline] [Order article via Infotrieve]
25. Vollmer RR. Selective neural regulation of epinephrine and norepinephrine cells in the adrenal medulla: cardiovascular implications. Clin Exp Hypertens. 1996;18:731-751.
26. Betito K, Diorio J, Boksa P. Brief cortisol exposure elevates adrenal phenylethanolamine N-methyltransferase after a necessary lag period. Eur J Pharmacol. 1993;238:273-282.[Medline] [Order article via Infotrieve]
27.
Esler M, Jennings G, Korner P, Willet I, Dudley F,
Hasking G, Anderson W, Lambert G. Assessment of human
sympathetic activity from measurements of norepinephrine
turnover. Hypertension. 1988;11:3-20.
28.
Anderson EA, Sinkey CA, Lawton WJ, Mark AL.
Elevated sympathetic nerve activity in borderline hypertensive
humans. Hypertension. 1989;14:177-183.
29. Barnes PJ. Beta-adrenergic receptors and their regulation. Am J Respir Crit Care Med. 1995;152:838-860.[Medline] [Order article via Infotrieve]
30. Gavras H, Handy D, Gavras I. Alpha-adrenergic receptors in hypertension. In: Laragh JH, Brenner BM, eds. Hypertension: Pathophysiology, Diagnosis and Management. New York, NY: Raven Press; 1995:853-861.
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