scholarly journals The aging effect: The relationship of twist to structural and mechanical remodeling of the left ventricle in a normal population using HARP CMRI

2010 ◽  
Vol 12 (S1) ◽  
Author(s):  
Danielle M Janosevic ◽  
Nora Ngai ◽  
Marguerite Roth ◽  
William Schapiro ◽  
Simcha Pollack ◽  
...  
Keyword(s):  
Left Ventricle ◽  
Normal Population ◽  
Aging Effect ◽  
Mechanical Remodeling ◽  
Relationship Of ◽  
The Relationship

Striatal 18F-DOPA Uptake: Absence of an Aging Effect

1993 ◽  
Vol 13 (5) ◽  
pp. 881-888 ◽  
Author(s):  
D. Eidelberg ◽  
S. Takikawa ◽  
V. Dhawan ◽  
T. Chaly ◽  
W. Robeson ◽  
...  
Keyword(s):  
Aging Process ◽  
Aging Effect ◽  
Normal Subjects ◽  
Normal Aging ◽  
Kinetic Rate ◽  
Positron Emission ◽  
Kinetic Rate Constants ◽  
The Subject ◽  
Relationship Of ◽  
The Relationship

l-[18F]6-Fluoro-DOPA (l-[18F]6-fluoro-3,4-dihydroxyphenylalanine; FDOPA) has been used with quantitative positron emission tomography (PET) to assess presynaptic nigrostriatal dopaminergic function in life. The relationship of estimated kinetic rate constants for striatal FDOPA uptake [ Ki(FDOPA)] to the normal aging process has been the subject of conflicting reports. Resolution of this issue has been hampered by methodological differences in previous FDOPA/PET investigations. We studied 19 healthy normal subjects (aged 27–77 years) and measured striatal Ki-(FDOPA) according to each of the earlier methods. While significant correlations (p < 0.005) existed between Ki(FDOPA) values estimated by the various techniques, none correlated with normal aging. We conclude that normal striatal Ki(FDOPA) values estimated using quantitative FDOPA/PET are uncorrelated with the aging process.

SKIN INFECTIONS AND ACUTE NEPHRITIS IN AMERICAN INDIAN CHILDREN

PEDIATRICS ◽  
1967 ◽  
Vol 39 (2) ◽  
pp. 263-279
Author(s):  
Bascom F. Anthony ◽  
Lawrence V. Perlman ◽  
Lewis W. Wannamaker
Keyword(s):  
Normal Population ◽  
Skin Lesions ◽  
Skin Infections ◽  
Upper Respiratory Tract ◽  
Indian Children ◽  
Superficial Skin ◽  
Group A ◽  
Relationship Of ◽  
The Relationship

Serial observations were obtained over an 18-month period of 270 Indian children with pyoderma. Beta-hemolytic streptococci, predominantly group A, and coagulasepositive staphylococci were recovered from the majority of lesions (80% and 70%, respectively), both on the initial and on subsequent cultures. The predominant agglutination patterns of streptococcal strains were similar to those described in other studies of superficial skin infections. Another agglutination pattern, 17/23/47, not previously observed to be prevalent in streptococci from skin lesions, was identified in a significant number of skin cultures. In addition, the hitherto undescribed association of M-types, including type 41 and a new M-type, with strains of T-agglutination pattern 3/13/B3264 was found. In striking contrast to the streptococcal strains, established "impetigo" strains of Staph. aureus (type 71 or other group II strains) were in the minority. Throat cultures of children with pyoderma suggested a limited relationship between infection or colonization of the pharynx and infection of the skin, while nasal streptococci were more closely correlated with and possibly derived from the flora of the skin lesions. Titers of ASO were not often elevated over control values in children with pyoderma, while anti-DNAse B titers were more commonly increased. Group A streptococci isolated from skin lesions prior to or at the time acute nephritis was recognized included type 12 (M and T) and strains classified by T-agglutination as 5/27/44, 11 and 4. The role of infection or colonization of the upper respiratory tract in the relationship of pyoderma to nephritis was not clarified in these studies. Moreover, in view of the frequency of change of group A streptococcal strains in skin lesions, as shown in serial observations in this study, the nephritogenic significance of streptococci recovered from skin lesions at the time of recognition of nephritis must remain in some doubt. Questions concerning the pathogenesis of endemic nephritis associated with pyoderma can probably be most reliably answered by frequent, prospective observations of a normal population with significant occurrence of streptococcal skin infections.

Relationship of coronary flow and perfusion territory in dogs

1982 ◽  
Vol 243 (5) ◽  
pp. H738-H747 ◽  
Author(s):  
K. W. Scheel ◽  
L. A. Ingram ◽  
R. L. Gordey
Keyword(s):  
Left Ventricle ◽  
Coronary Flow ◽  
Flow Distribution ◽  
Strong Correlations ◽  
Volume Weight ◽  
The Right ◽  
Relationship Of ◽  
The Relationship ◽  
Myocardial Flow ◽  
Perfusion Territory

In this study the relationship between myocardial flow and perfusion territory at maximal vasodilation was examined for the left anterior descending (A), circumflex (C), right (R), and septal (S) coronary arteries. Average flows to A, C, R, and S were 31.2 +/- 1.5 (SE), 41.2 +/- 13.5 +/- 0.6, and 14.1 +/- 0.6% of total coronary flow. Strong correlations were found between weight and volume, weight and coronary flow, and weight and resistance of the perfusion territories of A, C, R, and S. However, coronary flow (milliliter per minute per gram) to the right ventricle was significantly lower than to the left ventricle. Examination of the distribution of perfusion territories from base to apex of the heart showed that the anterior descending territory increases from base to apex, whereas the right decreases from base to apex. Circumflex flow distribution is relatively uniform between these limits, and the septal artery is most pronounced at midlevel and tapers toward the apex and base.

Origin of great cardiac vein and coronary sinus drainage within the left ventricle

1976 ◽  
Vol 230 (2) ◽  
pp. 486-492 ◽  
Author(s):  
DL Roberts ◽  
HK Nakazawa ◽  
FJ Klocke
Keyword(s):  
Steady State ◽  
Left Ventricle ◽  
Coronary Sinus ◽  
Marginal Vein ◽  
Great Cardiac Vein ◽  
Before And After ◽  
Arterial Inflow ◽  
Sinus Drainage ◽  
Relationship Of ◽  
The Relationship

The relative contributions of left anterior descending (LAD) and left circumflex (LC) arterial inflow to blood sampled at various points within the great cardiac vein (GCV) and coronary sinus (CS) have been investigated in open-chest dogs. Dissolved helium (He) and hydrogen (H2) were infused into external circuits perfusing the LAD and LC, respectively, and their steady-state concentrations were measured chromatographically at various points within the GCV and CS. Under basal conditions GCV H2 averaged only 5% of mid-CS H2 and did not change greatly during alterations of preload and afterload or during selective LAD or LC obstruction and vasodilation. The relationship of mid-CS He to GCV. He was more variable under basal conditions and changed noticeably during selective changes in LAD or LC inflow. Appreciable amounts of He were present consistently in left marginal vein drainage. We conclude that: 1) GCV blood is remarkably free of LC inflow in both normal and abnormal physiological states; 2) the origin of mid-CS blood is more variable, both from animal to animal and in individual animals before and after interventions; 3) a portion of LAD drainage normally reaches the CS through circumflex venous branches rather than the GCV.

Personality and Meditation

1976 ◽  
Vol 43 (3) ◽  
pp. 787-792 ◽  
Author(s):  
Paul Williams ◽  
Anthony Francis ◽  
Robert Durham
Keyword(s):  
Transcendental Meditation ◽  
Normal Population ◽  
Relationship Of ◽  
The Relationship

The relationship of psychoticism, extraversion-introversion, and neuroticism to the practice of Transcendental Meditation was studied. Male meditators ( n = 39) were more introverted and more neurotic than the normal population, whereas the female meditators ( n = 27) had a higher mean psychoticism score. Over a 6-mo. period of meditation, the males ( n = 24) became less neurotic; the degree to which they did so was related to the frequency of meditation. The implications of these findings are discussed.

scholarly journals Golden symmetry - an indicator of the norm and pathology of the human heart

2020 ◽  
Vol 22 (2) ◽  
pp. 189-194
Author(s):  
Yu. S. Malov ◽  
A. N. Kuchmin ◽  
I. M. Borisov ◽  
A. M. Malova
Keyword(s):  
Blood Pressure ◽  
Left Ventricle ◽  
Human Heart ◽  
Golden Ratio ◽  
Symmetry Transformation ◽  
The Body ◽  
Healthy People ◽  
Mechanical Activity ◽  
Relationship Of ◽  
The Relationship

The concept of norm is the key to biology and medicine. Recently, the norm has been associated with harmony. That which leads opposites to unity is harmony. It is closely related to the proportion of the golden ratio. The golden ratio is the basis of human health. Deviations from it can be used in medicine to diagnose pathological conditions. This fully applies to the work of the heart. The mathematical expression of harmony, symmetry is a method of assessing the norm of the heart. The golden proportion is manifested in the relationship of the temporal parameters of the cardiocycle, volumes of the left ventricle, types of blood pressure: pulse, diastolic, systolic. It was found that the golden proportions of systole, diastole and cardiocycle close to 0,382,0,618 are observed in men with a heart rate of 65 beats/min, in women - 55 beats/min. This mode of work of the heart corresponds to the rest of the body and is the norm. During physical activity, changes in the parameters of the cardiocycle occur (symmetry transformation). Violations of the golden relationship of the phases and the cardiocycle indicate damage to the heart. The magnitude of these deviations from the golden ratio depends on the severity of heart failure. Golden harmony in healthy people can be traced in the relations between the volumes of the left ventricle. These relationships are the ideal norm. Deviations in the relationship of volumes from golden ratio are a manifestation of pathology. Based on the principle of golden symmetry in healthy people, the normal EF is 623%, and not 50-80% as is accepted in practice. It is not an indicator of the norm. The mechanical activity of the heart is also determined by the laws of harmony. Pulse, diastolic and systolic blood pressure in healthy individuals are among themselves in the golden ratio (0,618). Violations of golden ratio are found in unstable forms of hypertension and damage to the heart muscle. Golden symmetry is the basis of the reference of the norm and the identification of pathologies of the human heart.

The relationship of the scleractinian corals to the rugose corals

Paleobiology ◽  
1980 ◽  
Vol 6 (02) ◽  
pp. 146-160 ◽  
Author(s):  
William A. Oliver
Keyword(s):  
Critical Points ◽  
Scleractinian Corals ◽  
Convincing Evidence ◽  
Early Triassic ◽  
Rugose Corals ◽  
History Of ◽  
The Subject ◽  
Relationship Of ◽  
The Relationship ◽  
Biologic Factors

The Mesozoic-Cenozoic coral Order Scleractinia has been suggested to have originated or evolved (1) by direct descent from the Paleozoic Order Rugosa or (2) by the development of a skeleton in members of one of the anemone groups that probably have existed throughout Phanerozoic time. In spite of much work on the subject, advocates of the direct descent hypothesis have failed to find convincing evidence of this relationship. Critical points are:(1) Rugosan septal insertion is serial; Scleractinian insertion is cyclic; no intermediate stages have been demonstrated. Apparent intermediates are Scleractinia having bilateral cyclic insertion or teratological Rugosa.(2) There is convincing evidence that the skeletons of many Rugosa were calcitic and none are known to be or to have been aragonitic. In contrast, the skeletons of all living Scleractinia are aragonitic and there is evidence that fossil Scleractinia were aragonitic also. The mineralogic difference is almost certainly due to intrinsic biologic factors.(3) No early Triassic corals of either group are known. This fact is not compelling (by itself) but is important in connection with points 1 and 2, because, given direct descent, both changes took place during this only stage in the history of the two groups in which there are no known corals.

Skeletal elements of crinoid echinoderms: High-resolution structural and microanalytical results

1983 ◽  
Vol 41 ◽  
pp. 194-195
Author(s):  
D. F. Blake ◽  
L. F. Allard ◽  
D. R. Peacor
Keyword(s):  
High Resolution ◽  
Marine Invertebrates ◽  
Sea Urchins ◽  
Structural Features ◽  
Sea Stars ◽  
High Resolution Tem ◽  
Relationship Of ◽  
The Relationship ◽  
Insight Into

Echinodermata is a phylum of marine invertebrates which has been extant since Cambrian time (c.a. 500 m.y. before the present). Modern examples of echinoderms include sea urchins, sea stars, and sea lilies (crinoids). The endoskeletons of echinoderms are composed of plates or ossicles (Fig. 1) which are with few exceptions, porous, single crystals of high-magnesian calcite. Despite their single crystal nature, fracture surfaces do not exhibit the near-perfect {10.4} cleavage characteristic of inorganic calcite. This paradoxical mix of biogenic and inorganic features has prompted much recent work on echinoderm skeletal crystallography. Furthermore, fossil echinoderm hard parts comprise a volumetrically significant portion of some marine limestones sequences. The ultrastructural and microchemical characterization of modern skeletal material should lend insight into: 1). The nature of the biogenic processes involved, for example, the relationship of Mg heterogeneity to morphological and structural features in modern echinoderm material, and 2). The nature of the diagenetic changes undergone by their ancient, fossilized counterparts. In this study, high resolution TEM (HRTEM), high voltage TEM (HVTEM), and STEM microanalysis are used to characterize tha ultrastructural and microchemical composition of skeletal elements of the modern crinoid Neocrinus blakei.

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