Comparative Hemolysis Tests of Rotary Blood Pumps

Abstract: At present, hemolysis is one of the most important characteristics used to evaluate rotary blood pumps. However, the conditions of testing procedures in various research centers differ considerably. We proposed to conduct the experiments under conditions similar to those from clinical applications of arterial pumps in ex-tracorporeal perfusion. Proceeding from these considerations, the following parameters of Hemolysis (H) testing were adopted: output, 6 L/min; difference of pressure, 300 mm Hg; initial hematocrit, 30 mg%; and initial hemolysis (PHbo) <5 mg%. The channel pump IBP80 designed on the basis of the BP80 was tested using fresh human blood. The experimental results indicate that the H level due to the use of the IBP80 is 2–3 times less than H for the BP80. H dependence on the difference of pressure in the range between 200 and 300 mm Hg was noted for the BP80, which can be accounted for by the transition of the laminar conditions of flow to turbulence. According to the results of the hydrodynamic efficiency evaluation, the IBP80 is twice as efficient as the BP80.     

Doxorubicin complexes with copper ions of the active center of ceruloplasmin

Features of the interaction of doxorubicin (DR) with Cu²⁺ ions of the active center of ceruloplasmin (CP) have been studied by electronic spectroscopy. It is established that DR · Cu²⁺ CP and DR complexes with inorganic copper salts (Cu(CH₃COO)₂ and CuSO₄) have the same chromophore. An equation establishing a relationship between the electronic absorption at 540 nm (chromophore absorption region) and the concentration of DR involved in the complex formation is proposed. Using this dependence in accordance with the Benesi-Hildebrand theory, the complex formation constant was approximately evaluated as K_p = 4.5 × 10⁶. Effective complex formation between DR and Cu²⁺ ions of the CP active center creates prerequisites for the removal of Cu²⁺ ions from CP and, consequently, for a decrease in CP oxidase activity. __________ Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 40, No. 5, pp. 49–53, May, 2006.     

Medium molecular weight blood peptides as factors modifying erythrocyte membranes in burns

Departments of Biochemistry and Normal Physiology, Chelyabinsk Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR V. N. Orekhovich.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 106, No. 12, pp. 666–668, December, 1988.     

Clinicopathologic study of 97 cases of small renal cell carcinomas using DNA flow cytometric analyses

The incidence of small renal cell carcinomas (RCC) has Increased recently as diagnostic imaging techniques have improved. The Indications for partial nephrectomy for small RCC confined to the kidney are still controversial. Ninety-seven small RCC 2.5 cm or smaller, Including incidental, occult, and dialysis associated carcinomas obtained at surgery or autopsy were examined. Various clinicopathologic parameters were assessed and survival was analyzed using the Kaplan-Meir method. Seventy-eight cases were incidental carcinomas. Carcinomas caused death in five cases, four of which had Initial signs of metastatic disease. Differences in survival between patients with expansive and invasive (intermediate and infiltrating) growth patterns, solid and other structural patterns, clear and other cell types, grade 1 and higher grades of nuclear atypla, and with and without lymph node metastasis were statistically significant All surgical cases were alive except one who died of another disease. Poor prognostic factors seen in five fatal autopsy cases included invasive growth pattern, solid structural pattern, spindle cells, grade 3 nuclear atypia, and Bellini duct carcinoma. Small RCC may be treated with partial nephrectomy provided they do not show these features, although there is low risk of recurrence or development of de novo cancer.     

The interaction of neurons characterized by a tonic reaction to sound with other neurons in the cat auditory cortex

Interaction of neurons with tonic response to sound with adjacent or distant (approximately 400-500 micrograms) cortex neurons was studied in acute experiments on 15 immobilized cats using a method of the cross-correlation analysis. A presence of synchronizing excitatory input common for the cells has been revealed in 26 pairs (72%) on the cross-correlograms. The results of the cross-correlation analysis in five pairs of neurons show mono- or polysynaptic excitatory effect of a tonic neuron to impulse activity of another neuron. Negative correlation indicative of the inhibitory influence of tonic neurons on impulse responses of other neurons of the same or adjacent auditory cortex column is revealed in five pairs of neurons, but the inhibitory influences may be considered as monosynaptic ones only in 3 pairs of these neurons (latency of interaction 1.0-1.5 ms). The data obtained permit concluding that the group of neurons characterized by tonic response to sound is a heterogeneous one in the functional respect. An assumption that some neurons of the tonic type are inhibitory interneurons of the auditory cortex, other excitatory ones is under discussion.     

Synergistic Antitumor Interaction of Human Monocyte Chemotactant Protein-1 Gene Transfer and Modulator for Tumor-Infiltrating Macrophages

Purpose. In order to evaluate the possibility of synergistic antitumor gene therapy by the gene delivery of monocyte chemotactant protein-1 (MCP-1/MCAF/IE), the effect of a biological response modulater for macrophages on tumor progression of gene transfected tumor cells was studied. Methods. Cachexia-inducing adenocarcinoma cells (cell line colon 26, clone 20) were transfected with either a control plasmid or MCP-1 cDNA. Results. The production of MCP-1 reached 70-80 ng/ml in vitro when transfectant cells were cultured at a cell density of 1 × 10⁵ cells/ml for 3 days. Transfection of MCP-1 cDNA did not affect the growth ratein vitro. Also, MCP-1-transfectants formed tumors after intra-footpad inoculation similar in size to the parental cells. The number of infiltrating macrophages in the primary tumor of the transfectant rapidly increased from the 3rd to 5th day after inoculation as revealed by immunohistochemical staining using an antibody against mouse macrophages. An earlier, greater, but no longer-lasting increase in tumor-infiltrating macrophages was induced in tumors by MCP-1 transfection was compared to that induced by the parent cells. On the 10th day after the inoculation, the tumor-infiltrating macrophages in mice inoculated MCP-1 transfectants were decreased to a level similar to that of the parent cells. Groups of mice were treated intraperitoneally with LPS at different times after the inoculation. Tumor cells producing high levels of MCP-1 were significantly lysed by macrophages treated with LPS, whereas parental or control transfected cells were not. Conclusions. Combination immunotherapy can provide a rationale for the application of MCP-1 treatment to increase immunological responses to cancer.