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At least 109 records · Page 6Linked to original sources
PubMed1991

[Insomnia and its treatment in aged persons: a new approach].

Existing hypotheses regarding psychological mediation of disorders in initiating and maintaining sleep only partially explain the phenomenon of insomnia, particularly in aging individuals. In this article we review existing nonpharmacological treatments of insomnia and propose a new way of conceptualizing and treating disorders of initiating and maintaining sleep. The model, based on cognitive and information processing factors, is then used to propose novel approaches to intervention. Because of the prevalence of sleep disruptions in older adults and the limitations of existing pharmacological and psychological treatments with this population, the assumptions of the model and the proposed intervention are explored with particular reference to aging individuals.

Aged↗
PubMed1979

[Possibilities and limits for palsied children in the general polytechnical school (author's transl)].

Some children with cerebral palsy attend the ten-form general polytechnical school. To this end, several prerequisites have to be fulfilled and other essential arrangements to be developed in cooperation with specially trained teachers. The learning conditions have to be fitted to the improving abilities of children during the educational process. Factors of influence and cooperation modes are discussed.

Adolescent↗
PubMed1979

[The psychophysiology of the visual thought perception of visually evoked brain potentials and recognition mechanisms].

The study tries to demonstrate, that the combination of the actualgenetic method (Sander, Froehlich), and the VEP, allows a systematic and differentiated analysis of the psychophysiological process of visual thinking. A student group was compared with mental retardates in VEP and EOG, watching actualgenetically manipulated picture series. Phasic EEG-changes are significantly related to the identification process. Most sensitive are amplitude changes about 120 to 270 msec. The mental retardates had significant VEP changes 180--270 msec, the students 128--192 msec after picture presentation. The process factor analysis (Pawlik) elaborated an illumination factor and two factors being labelled general reaction set. VEP averaging over the persons revealed different attention and/or discrimination behavior for the student group and the mental retardates, identifying the picture objects.

Adult↗
PubMed1991

Cleavage of the membrane precursor for transforming growth factor alpha is a regulated process.

Transforming growth factor alpha (TGF-alpha) is generated by cleavage of a membrane-anchored precursor protein, proTGF-alpha. ProTGF-alpha is cleaved at a slow rate and accumulates on the cell surface, thereby mediating cell-cell adhesion and mitogenic stimulation. We show here that cleavage of membrane proTGF-alpha by an elastase-like enzyme constitutes an important regulatory step in the generation of soluble TGF-alpha. Cleavage is activated in response to serum factors and tumor-promoting phorbol esters, leading to depletion of cell surface proTGF-alpha, which disperses as soluble factor. Activation of proTGF-alpha cleavage is mediated by protein kinase C-dependent and -independent mechanisms. The results demonstrate the existence of mechanisms that control the switch of TGF-alpha from a juxtacrine to a paracrine growth factor.

Animals↗
PubMed1992

[Role of cytokines and growth factors in joint destruction processes].

Cytokines and growth factors are important mediators of inflammatory reactions and play a central role in the physiologic regulation of bone and cartilage cell activities and in joint destruction. The net effects of cytokines on target tissues depend on the relative pericellular concentrations of several cytokines and their inhibitors in the inflammatory tissue. It is possible to suppress the effects of cytokines with natural or synthetic inhibitory molecules. The measurement of cytokines and their inhibitors may be useful to understand the pathogenesis and to develop new therapies for inflammatory joint diseases. In this review the following cytokines will be reviewed: interleukin 1 and its inhibitor, tumor necrosis factor alpha and its inhibitor, interleukin 6, interferon gamma, transforming growth factor beta, colony-stimulating factors, fibroblast growth factors, platelet derived growth factor and prostaglandins.

Arthritis↗
PubMed1977

The styloid process syndrome: aetiological factors and surgical management.

The literature on the syndromes associated with the styloid process is reviewed. The anatomy and embryology of the styloid apparatus are then discussed in relation to the development of these conditions; attention is drawn to the significance of elongation of the process. Eighty styloids measured at post-mortem examination enabled a mean length to be determined as well as a range of normals. The possible aetiological factors are then listed. Four cases of elongated styloid process are described, three treated by excision via an external approach and the fourth presenting as an asymptomatic lump in the neck, not requiring treatment. The authors' preference for the external approach is explained.

Congenital Abnormalities↗
PubMed1989

Identification of mRNA coding for factor VII protein in human alveolar macrophages--coagulant expression may be limited due to deficient postribosomal processing.

Clotting factors synthesized by monocytes and macrophages may initiate coagulation reactions during inflammation. Functional vitamin K-dependent coagulation factors have been found to be associated with human monocytes/macrophages, but there are no reports identifying mRNA coding for vitamin K-dependent proteins in these cells. In the present studies, factor VII mRNA was found in total RNA extracted from freshly isolated human alveolar macrophages using hybridization with a complementary DNA probe. On the other hand, vitamin K-dependent carboxylase activity which is required for postribosomal modification of the protein, was not detectable in the macrophages before or after culture, and human blood mononuclear leukocytes also lacked this enzyme activity. Control human and rat hepatoma cells exhibited high levels of carboxylase activity within the same experiments. Using sensitive kinetic assays, no increase in factor VII activity was detected during culture of alveolar macrophages under conditions promoting 1.78 +/- .24 (n = 8) fold increases of tissue factor activity. These findings with freshly isolated cells demonstrate that alveolar macrophages synthesize factor VII mRNA in vivo. However, the mRNA was found in the absence of evidence for gamma-carboxylase activity or processing of the factor into a functional clotting enzyme. The results imply that functional expression of any synthesized coagulation factor VII in alveolar macrophages may be limited or prevented due to a cellular deficiency at the level of postribosomal processing.

Carbon-Carbon Ligases↗
PubMed1990

Antigen processing and presentation in vivo: the microenvironment as a crucial factor.

Antigen processing and presentation in vitro is an increasingly well understood phenomenon. However, in vivo, a large number of variables conspire to obscure and confuse. In this article, Nico van Rooijen attempts to bring order to events that occur in the spleen after antigenic challenge: starting with the large body of reliable in vitro data he incorporates information on splenic anatomy, cell trafficking and the cellular microenvironment to arrive at a physiological model for antigen handling in vivo.

Animals↗
PubMed1975

[A factor influencing the process of chromatin condensation in hepatocytes of regenerating rat liver].

It was shown with the model supramolecular chromatin systems that the activity of the factor of chromatin condensation changes in the process of liver regeneration. No activity of the factor of chromatin condensation was found 20 hrs after operation. Within 32-33 hrs (in the period of increased mitotic frequency) its activity approaches that prior to the operation. The nature of the activity of the factor of chromatin condensation is discussed with respect to the functional state of chromatin.

Animals↗
PubMed1987

Identification of a peptidase which processes atrial natriuretic factor precursor to its active form with 28 amino acid residues in particulate fractions of rat atrial homogenate.

With the objective of identifying specific peptidase responsible for the processing of atrial natriuretic factor precursor pro-ANF to the circulating active form ANF (99-126), a fluorometric assay method was devised using synthetic fluorogenic substrate Boc-Ala-Gly-Pro-Arg-MCA(methylcoumarinamide) which contains the amino acid sequence immediately adjacent to the arginyl peptide bond which is cleaved in the natural processing of pro-ANF. A protease which selectively cleaves this bond and produces the natural circulating peptide was identified in the particulate fraction of rat atrial homogenate and was solubilized by 1.6 M KCl. It was partially purified by affinity chromatography heparin-agarose column and was shown to be a serine protease. Its reaction product with natural pro-ANF was identified as ANF (99-126) containing 28 amino acid residues.

Animals↗
PubMed1992

[Effects of acyclic analogs of atrial natriuretic factor on proliferative processes of the epithelial tissue in white rats].

The effect of atrial natriuretic factor (ANF) synthetic linear truncated analogues AP-H-6-OH and AP-FOR-6-OH on corneal, skin, duodenum and colon epithelium proliferation has been studied on male rats. The epithelium mitotic activity and DNA synthesis were evaluated 4 and 24 h after intraperitoneal injection of 10 or 100 micrograms/kg peptides. In a dose of 10 micrograms/kg both ANF synthetic analogues inhibited proliferation processes in corneal epithelium, but activated the DNA synthesis in duodenum and colon epithelium. AP-FOR-6-OH (10 micrograms/kg) decreased the mitotic activity of skin epithelium and increased the silver grain density over the cell nuclei at the same time. 100 micrograms/kg ANF analogues stimulated cell mitogenesis in all organs studied. According to the data obtained ANF linear truncated analogues influence on epithelium proliferation is similar to effector of previously studied cyclic atriopeptin AP II.

Animals↗
PubMed1990

[Rabies prognosis in western Siberia and the regulatory factors of the epizootic process].

In this article the regulatory factors of the epizootic process are considered and the spatial-temporal prognostication of rabies infection in the region is proposed on the basis of data on rabies morbidity among animals, the purchase of skins of carnivorous animals for 20-25 years, virological experiments on wild animals, calculation of the number of carnivores and small mammals, as meteorological observations. The study has shown that a variety of animal species serving as hosts for the virus and its population differences contribute to the stable existence of the infection. Rabies morbidity has been found to be positively linked with its preceding level, the number of wild animals, the height and hardness of the snow cover and negatively with the number of small mammals.

Animals↗
PubMed1991

The aging process: major risk factor for disease and death.

Aging is the accumulation of changes responsible for the sequential alterations that accompany advancing age and the associated progressive increases in the chance of disease and death. Average life expectancies at birth in the developed countries are now approaching plateau values as the aging changes associated with the environment and disease near irreducible levels. The inborn aging process is now the major risk factor for disease and death after around age 28 in the developed countries and limits average life expectancy at birth to approximately 85 years. Future significant increases in average life expectancy--a rough measure of the healthy, productive life-span, i.e., the functional life-span--in these countries will be achieved only by slowing the rate of production of aging changes by the aging process. Many theories have been advanced to account for the aging process. The free radical theory of aging is discussed briefly. The importance attached to increasing the functional life-span dictates that aging hypotheses be explored for practical means of achieving this goal while work continues toward a consensus on the cause(s) of the aging process. Efforts to further increase the functional life-span by conventional measures are now almost futile, whereas those directed toward slowing the aging process are just beginning. These new efforts show promise.

Aging↗
PubMed1977

[The importance of risk factors in cerebrovascular processes while taking oral contraceptives (author's transl)].

21 young female and 15 young male patients with cerebrovascular insults were examined for risk factors. 14 of the 15 male patients showed clear cut risk factors: obesity, diabetes, hyperlipidemia, arterial hypertension, smoking, thromboses, vitium cordis. 20 of the 21 female patients took oral contraceptives. 60% of the female patients with angiographically confirmed stenoses and occlusion did not show any other risk factor. These results support the hypothesis that oral contraceptives are in themselves a risk factor.

Adult↗