Penetration and proliferation of BHK and HeLa cells into a three-dimensional collagen matrix of bone stroma type. Preliminary results

Some preliminary data regarding the test of penetration and proliferation of BHK and HeLa cells biocompatibility to a three dimensional stroma saturated with phosphorous and calcium salts (a biomaterial replacing bone) are presented. These data suggest that the analysed biomaterial might be used in surgical practices of prosthesis appliance on interfaces of fractured bone.     

Effect of pentobarbital on neuronal inhibitory response evoked in an isolated slab of cat auditory cortex by intracortical stimulation

Neuronal responses of an acutely isolated slab of auditory cortex (area AI) to intracortical electrical stimulation were studied intracellularly in cats anesthetized with pentobarbital. It was found that 77% of responses were primary IPSPs, and allowing for secondary inhibitory responses, an inhibitory response was observed in 92% of neurons. All types of neuronal responses in the slab were short-latency. The maximal response latency did not exceed 5 msec. Neurons responding to stimulation by IPSPs were found at all depths in the slab, with a maximum in layers II–III. Nearly all primary IPSPswere mono- and disynaptic. Pentobarbital increased the duration of individual neuronal inhibitory responses in the isolated slab of auditory cortex without affecting maximal duration of the IPSP. The mechanisms of the effect of pentobarbital on the amplitude and duration of IPSPs are discussed.I. I. Mechnikov Odessa State University. Translated from Neirofiziologiya, Vol. 16, No. 2, pp. 147–152, March–April, 1984.     

The production of hematopoietic growth factors by endothelial accessory cells

Monocytes are known to produce both hematopoietic growth factors and other factors, monokines, which do not directly stimulate hematopoiesis. Monokines such as interleukin-1 (IL-1) and tumor necrosis factor (TNF) may indirectly stimulate mesenchymal cells to produce hematopoietic growth factors. The identity of all the factors produced by monocytes or mesenchymal cells has not been established because of overlapping activities on biologic assay. The purpose of this study was to identify the individual growth factors produced by endothelial cells before and after stimulation with various monokines. We prepared conditioned media and extracted RNA from endothelial cells before and after stimulation with monokines. The results show that immortalized endothelial cells produce maximal detectable amounts of granulocyte-macrophage colony-stimulating factor (GM-CSF) constitutively. In contrast, GM-CSF production by primary endothelial cells requires induction with either IL-1 or TNF.     

Rectangular game theory and metabolic response to random changes in environmental states

Rectangular game theory is applied to the response of organisms to random environmental changes: A hypothetical example of the response of a facultative algae to random changes in illumination is analyzed. Two strategies are discussed: Bayes' risk and maximin. It is shown how to detect such strategies in populations. The analysis does not require assumptions about the form of the relationship between metabolic activities and selective advantage, but assumptions about evolutionary optimization are required. The maximin strategy is shown to be related to metabolic homeostasis.     

Demographic genetic approach in anthropologic research. II. A method for calculating the coefficient of consanguinity in a complex nongraphic pedigree

A simplified method of manual calculation for inbreeding coefficient (and/or relationship) from complicated pedigree tables presented in a nongraphic mode is offered. The method is based on the use of positional dual codes of ancestors in which all genealogical links of the proband are reflected.     

Merkel cell tumor: diagnosis, prognosis, and management

The histologic features of the Merkel cell and the pathologic characteristics of the Merkel cell tumor are described. From a literature review, 68 cases are examined; 23 cases that have been followed up accurately are presented from the Mayo Clinic. A representative case is used to demonstrate the problems of diagnosis and suggested treatment. The latter should be wide local resection with removal of nodal metastases if present. When indicated, this should be followed up with radiation therapy. Chemotherapy is of little or no value. Survival rates are presented.