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L Eckes

Publications and source records attributed to L Eckes.

13 recordsLinked to original sources

Risk factors associated with alterations in carotid intima-media thickness in hypertension: baseline data from the European Lacidipine Study on Atherosclerosis.

BACKGROUND: The possibility that calcium antagonists exert an anti-atherosclerotic action at least partly independently of the blood-pressure-lowering effect is supported by results of a large number of experimental studies and can now be investigated by quantitative B-mode ultrasound imagining of the carotid artery walls. DESIGN: The European Lacidipine Study on Atherosclerosis (ELSA) is a prospective, randomized, double-blind, multinational trial comparing effects of 4-year treatment based on the long-acting, highly lipophilic calcium antagonist lacidipine with those of treatment based on the beta-blocker atenolol on the development of carotid artery wall alterations in patients (aged 45-75 years) with mild-to-moderate hypertension (systolic blood pressure 150-210 mmHg and diastolic blood pressure 95-115 mmHg). While the intervention study is progressing, this article summarizes baseline data obtained from the whole cohort of 2259 patients randomly allocated to treatment. METHODS: Baseline ultrasound data were obtained from two replicate examinations performed shortly before random allocation to treatment by certified sonographers at 23 referral centres and read at the ultrasound coordinating centre at the Wake Forest University School of Medicine. Intima-media thickness was measured at up to 12 different sites in the carotid artery tree and expressed as the mean of the maxima at these sites (Mmax), the mean of the maxima at four sites in the distal common carotid artery and bifurcation (CBMmax) and the maximum intima-media thickness (Tmax). Baseline demographic and clinical measurements were performed by investigators in 410 peripheral clinical units and 24 h ambulatory blood pressure monitorings read and validated by members of a centralized unit at the University of Milan. The statistical analysis centre at the Technische Universität München received and analysed all baseline data, by calculating means +/- SD, medians and ranges and performing correlation (Spearman correlation coefficients) and multiple regression analyses. RESULTS: Prevalence of carotid artery wall alterations among the hypertensive patients randomly allocated to treatment in the ELSA was very high: 82% had Tmax > or = 1.3 mm ('plaques' according to protocol) and 17% had Tmax > or = 1.0 and < 1.3 mm ('thickening'), with a median of two plaques per patient. We found significant correlations between ultrasound measurements and the following demographic and clinical variables: age, sex, systolic blood pressure and pulse pressure (both clinic and ambulatory), concentrations of total, high-density lipoprotein and low-density lipoprotein cholesterol and triglycerides, smoking habit and duration of hypertension. We found no significant correlation to diastolic blood pressure and glucose concentration. A multiple regression analysis indicated significant variables in the following rank order: age, 24 h ambulatory pulse pressure, sex, low-density lipoprotein cholesterol concentration, triglyceride concentration, smoking and clinic systolic blood pressure. CONCLUSIONS: Analysis of baseline data from the ELSA has shown that there is an extremely marked prevalence of carotid artery wall alterations among mild-to-moderate, middle-aged hypertensive patients. In addition to age, systolic blood pressure and pulse pressure, particularly if they are accurately measured by ambulatory monitoring, play a major role, somewhat greater than those of sex, low-density lipoprotein cholesterol concentration and smoking, in influencing intima-media thickness.

Adrenergic beta-Antagonists↗

Influence of disulfiram, diethyldithiocarbamate and carbon disulfide on the metabolic formation of trifluoroacetic acid from halothane in the rat.

Halothane (H), 2-bromo-2-chloro-1,1,1-trifluoroethane, was metabolized to trifluoroacetic acid (TFAA) over a very long time (several days) in rats after a 1 h exposure to the inhalational anesthetic. H inhibited its own metabolism as long as anesthetically active concentrations existed in the serum and tissue. That fraction of H which was not exhaled rapidly by the lung after the anesthesia was metabolized mainly over the time range from 5-48 h: 68% of the total amount of TFAA eliminated in the urine during 144 h (about 4 mg) were found in this time period. Disulfiram (D) dose dependently inhibited the formation of TFAA from H in vivo and in vitro, in liver microsomes of phenobarbital treated rats. Diethyldithiocarbamate (DDTC) and carbon disulfide (CS2), two metabolites of D, given to rats immediately after the H-anesthesia also reduced the metabolic formation of TFAA. However, if DDTC and CS2 were given 24 h before the anesthesia they caused only a small decrease in serum TFAA concentration. This finding indicates that both metabolites of D have only short-lasting inhibitory effects. In contrast, the inhibition of the oxidative metabolism of H by D seems to persist over a long time, since a small but significant decrease in the serum TFAA concentration was found even if D was given 72 h before the H-anesthesia. It was concluded that in vivo CS2 is really the active inhibitor. The short-lasting inhibitory effect of DDTC may be explained by its fast metabolic transformation into CS2, whereas the long-lasting effect of D is caused by its delayed degradation into this metabolite.

Anesthesia, Inhalation↗

Psoriasis vulgaris and genetic markers.

In a sample of n = 160 nonrelated male and female patients suffering from psoriasis Vulgaris, blood serum protein, and enzyme group typings have been carried out and compared with healthy controls from the same area (Rheinland-Pfalz). Marked statistically significant differences between patients and controls were found in none of the genetic blood polymorphisms considered here. However, combining previously published data from various authors with our own, significant associations between this skin disease and genetic polymorphisms such as MN, Gc, Gm (2), red cell acid phosphatase, and red cell phosphoglucomutase (PGM1) were seen. The possible reasons for these associations are discussed.

Acid Phosphatase↗

[Classification of the abnormality concept].

This paper deals with congenital malformations in man and presents a classificatory system for them. It first distinguishes abnormalities from normal variation and then further separates between primary and secondary structural disorders. Secondary disorders are those which are due to disturbances in primary normal tissues. Every maldevelopment which originates in prenatal life, is a congenital malformation. The level at which the malformation occurs must be considered, i. e. whether it is at the organism level, organ level, tissue, cell or subcellular level. A standardized system is absolutely necessary if the incidence of malformations is to be compared throughout the world.

Abnormalities, Drug-Induced↗

[Altitude adaptation. Part III. Altitude acclimatization as a problem of human biology (II. Morphology, physiology, biochemistry)].

The physiological mechanisms of adaptation will be reported. In a primary step of adaptation, the body reacts with immediate response, which already leads to a first classification: whether or not altitude will be tolerated by an individual. More steady biological processes follow with the same intention of balancing oxygen deficiency. They may be successful and acclimatization is possible, or they do not achieve the necessary level, i.e. that consequently developing pathological conditions of different severity lead to a next assortation of individuals with insufficient adaptability. The first state of lability can be compensated, or the intolerance will make a further stay in high altitudes impossible. No parameters exist which could allow a prognosis as to what kind of individuals will tolerate altitude or not. A different pattern of biological reaction is seen in permanent inhabitants of high altitudes who have been residing there for generations and haven't experienced conditions other than those of their special altitude in their individual lives. While ascending to higher altitudes, permanent residents also have to undergo new adaptation, as well as when descending to lower altitudes. Returning to their native environment requires reacclimatization. The mechanisms of adaptation on the organ level will be reviewed, as well as on the fluid and cellular level. All those functional and morphological mechanisms of adaptation to oxygen deficiency in high altitudes tend to maintain optimal equilibrium. Maladaptation may result. Expected genetically determined physiological alterations of adaptational value in permanent residents, which could have manifested themselves by way of "soft" selection and change of gene frequency in those high altitude populations, will be discussed. Genetical determination in such physiological parameters does not seem probable, although some pecularities such as the "blunted response" ventilation, the higher Bohr-Effect in Quenchua etc. might be interpreted in this direction.

Acclimatization↗

[Altitude adaptation. IV. Fertility and reproduction at high altitudes].

High altitude populations have been reproducing for thousands of years. The mean total fertility is comparable to the respective mean values of the whole populations or is even higher. On the other hand, newcomers from sea level seem to have difficulties reproducing in high altitude, especially if they are caucasian. Cattle and other animals fail to reproduce to some extent (due to degeneration of the testes, asoospermia, abortation etc.), which can only be avoided after crossbreeding with aclimatized strains in several generations. But successful gestation in altitudes above 3000 metres is different from sea level gestation in several aspects, which may be important for the survival of mother and child, thus leaving open the question of selective pressure. The mean birth weight of man and animals is reduced, while the mean palcental weight is greater (relatively and absolutely) due to enlargement of the capillary volume. Placenta proves to be on higher risk for developing infarcts (the more in number and extetion, the greater the caucasian admixture). Due to the tendency to a greater extention of the surface, the rate of placenta praevia is extremely high (27%). The lower birth weight corresponds to a higher neonatal mortality, progressing with increasing altitude. Additional to the high altitude stress including the factors to which the newborn are exposed, such as cold, nuturtional deficiencies etc., particular socio-economic conditions influence the differential mortality. In the Bolivian mining-areas, mortality during the first year of life rises to 50%. Only high fertility rates compensate this loss so that high altitude population growth rates do not vary with the altitude.

Acclimatization↗

[Altitude adaptation. V. (conclusion). Morbidity and mortality. Literature].

The ability to adapt to extreme conditions is a continously working principle of man's evolution, in a permanent orientation to an optimal equilibrium between man and environment. A paradigm of biological adaptation is the condition of hypoxia at high altitudes, as one of the few environment constellations to which a pure biological and thus genetically based answer could be possible. The majority of adaptations are influenced by technological actions, which partially modify the environment in compensating unfavourable constellations (heating, clothing, housing, etc.). It is discussed, how far the adaptation to high altitudes produces transitory or permanent alterations with reference to constitution, perseverance, cold-sensitivity, diseases, duration of life, fertility, course of pregnancy, adaptations at the organ- and tissue-level, blood-composition, fluid-equilibrium of the body etc., which guarantee the survival of the individual and its successful reproduction with regard to the continuance of a mendel population. The elucidation of the question on genetic determination of features characteristic for high altitude inhabitants is difficult because we know next to nothing about the genetic determination of physiologic parameters. Studies on ethnic marker-genes (Ethiopia, South-America) give no reference to population differences. Remarkable is a striking prevalence of the blood-group O for all populations of high altitudes, but one must consider the effects of isolation in terms of the increase in the homozygote recessive alleles. We can propose, that in the primary settlement at high altitudes a "hard selection" was working, a kind of biological assortation-process from the beginning, which eliminated those individuals, who proved to be (for genetic reasons?) not adaptable. A good example for this are observations of cattle, from which 50% do not develop pulmonary hypertension when exposed to altitude, that means they already have a higher initial fitness. The non-adaptable animals have to be returned to the lowlands. In the F1-generation only 2% of the animals remaining at high altitude, develop "brisket disease". Possibly that means a sort of "out-mendeling" of "pulmonary-hypertension-genes", which may manifest themselves in the condition of hypoxia. Also the good adaptation of llamas is partially due to the fact that the camelids per se possess an outstanding O2 affinity and morphologically different red blood cells, which predispose this species to inhabit high altitudes. Parallel to considerations like these it could be imaginable, that e.g. the indianids of mongoloids in general, are genetically composed as fit to inhabit lowlands as well as highlands, in contrast to caucasoids and negroids. The largest mountain areas of the world (the Andes: 12 X 10(6)), the Himalayas 12 X 10(6)) are inhabited by populations of mongoloid ancestry, for about 10,000 years, a period, which ought to be long enough to make possible genetic specialisation, although it is not yet possible to prove it...

Acclimatization↗

[Altitude adaptation. Biological problems in the context of the environment].

The following part of the description of adaptation to high altitude describes the geographical specifities of the relevant regions of the world. There are several factors which require an adaptive answer, such as hypoxia, temperature, terrain, nutrition etc. The terms of genetically determined and of individual adaptation are discussed, with special consideration of a duration of settlement in the main altitude regions of about ten thousand years, as well as the principles of adaptation in general, including the phenomenon of maladaptation. The problem of adaptation of animals to high altitude is reviewed in short especially in regard to mammals. The differential fertility proves to be most important in the survival of a species in high altitude as well as the individual adaptability, is the fitness which makes high altitude tolerable to newcomers.

Acclimatization↗

[Altitude adaptation. Part II. Altitude adaptation as a problem of human biology. I. Growth)].

There are 3 main components influencing the mean stature of high altitude natives. The lower mean birthweight, which seems to result from the impossibility of complete adaptation during the last trimenon of gestation, which cannot be fully compensated during life. The general protein deficiency, or the habits of nutrition which are not comparable with the food-composition in industry-nations may be important. A definitive undernourishment has not been observed in those nations with longtime adaptation to the available food since generations, but several deficiencies of substances which specially influence growth, cannot be outruled. We also have to recognize the generally lower mean stature of the population in whole (South America Indians), that means of the both parents of a child. In the presence of low gene flow from one to the other generation this may influence also individual body measurement.

Acclimatization↗

[The simultaneous occurrence of psoriasis, sarcoidosis and gout. Report of 3 cases].

The author reports three further cases of simultaneous occurence of psoriasis, sarcoidosis and gout, additionally to the hitherto known observations. The occurence of gout is questionable in this connection, relevant seems to be only the coincidence of psoriasis and gout. A probable causal connection is discussed. This could theorectically be due to a common genetic sphere, to similar pathophysiological principles or to an alternatively manifestation of each other.

Adult↗

[The geographic distribution of psoriasis].

On the basis of data published in the literature the geographical distribution of psoriasis vulgaris is described. One of the most interesting results is the increase of the psoriasis frequency in countries such as Japan, Korea, Kazachstan and East Africa. This could be due to the fact, that altered life conditions in connection with an increasing industrialization favour the manifestation of psoriasis genes. How far population differences of the psoriasis frequencies are to be seen exclusively as genetical ones, is hitherto unclear, but rather unlikely. No relations between psoriasis and climatec factors could be seen. Associations between psoriasis and several antigens (HL-A 13 and W 17) of the HL-A-systems seem to be present. These associations could be of considerable importance for the interpretation of the geographical distribution pattern of psoriasis. Further studies in psoriatic families are required, which describe the distribution of the HL-A specifities in the possibly potential psoriatic members of the families, who carry the respective genes.

Africa↗