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Biomedical subjects

C Franzblau

Publications and source records attributed to C Franzblau.

At least 127 records · Page 7Linked to original sources
PubMed1981

The moderation of elastase-induced emphysema in the hamster by intratracheal pretreatment or post-treatment with succinyl alanyl alanyl prolyl valine chloromethyl ketone.

The capacity of the synthetic elastase inhibitor, succinyl alanyl alanyl prolyl valine chloromethyl ketone (CMK), to moderate elastase-induced emphysema in hamsters was examined using morphometric and physiologic measurements. When 0.5 mg of CMK in saline was injected intratracheally 1 h before the intratracheal injection of 0.1 mg of porcine pancreatic elastase, the hamsters did not develop emphysema. When CMK was injected intratracheally 1 h after elastase, the severity of emphysema was reduced by approximately 50% compared with control animals receiving saline 1 h after elastase. The CMK was ineffective when administered intratracheally 4 h after elastase.

Amino Acid Chloromethyl Ketones↗
PubMed1981

Formation of elastic fibers and elastin in rabbit aortic smooth muscle cell cultures.

Cultured rabbit aortic smooth muscle cells produce elastic fibers and elastin in their extracellular matrix. Morphological analyses of elastic fibers indicate that they consist of two distinct components which play a major role in elastic early fiber formation namely, the amorphous component and the "microfibrillar" component. During elastogenesis, the early fiber consists of small bundles of filaments. Later, clearly distinguishable small conglomerates of amorphous material are found distributed among the bundles of filaments. The mature elastic fibers have large conglomerates of amorphous material with the filaments present within the interstices. Long term cultures of these cells in the second passage continue to accumulate elastin. The crosslinking amino acid isomers desmosine and isodesmosine, which are unique to insoluble elastin, increase with time in culture. Twenty-four hour pulses with 14C-proline followed by measurements of 14C-hydroxyproline in the collagenase resistant protein of the cell layer show that the synthesis of insoluble elastin is constant up to the 14 week period studied from the time the amorphous material becomes evident ultrastructurally.

Amino Acids↗
PubMed1980

Synthesis of glycosaminoglycans by cultured rabbit smooth muscle cells.

Rabbit aortic smooth muscle cells were evaluated for their ability to synthesize and accumulate glycosaminoglycans (GAGs). Because of the sensitivity of the microtechniques utilized, it is possible to determine the specific radioactivity of the GAGs obtained after radioactive incorporation of [35S]SO4(2-) and [14C]glucosamine. Data obtained at various incubation times indicate that the distribution of the GAGs secreted by the cells into the medium is different from that retained by the cell layer. Hyaluronic acid was shown to be the most abundantly produced GAG, and much of this GAG does not appear to be incorporated into the extracellular matrix. Also, a high percentage of the total chondroitin sulfate B synthesized was secreted into the medium. On the other hand, most of the heparan sulfate and chondroitin sulfate C/A synthesized seems to be associated with the cell layer. These results are consistent with those found in whole rabbit aorta.

Animals↗
PubMed1980

A morphometric study of vascular smooth muscle cells in culture.

Cultured arterial smooth muscle cells derived from different times in culture, different passages, and different species were evaluated by a combination of transmission electron microscopy and morphometry. The morphometric studies focused on point counting and monitored the following cellular components: lysosomes, myofilaments, mitochondria, ribosomes, and rough endoplasmic reticulum (RER). Percent volume composition values for the organelles involved in protein synthesis, namely ribosomes and RER, show significant fluctuations with time. Consistent with these observations, the cells showed increasing myofilaments during the early weeks in culture, which subsequently decreased significantly. The data also indicate that rabbit cells in culture may become synthetically quiescent with time and the distribution of cellular components is altered with each succeeding passage. Cultured calf (bovine) cells exhibit similar activity periods compared to rabbit but show a significantly higher lysosomal and lower myofilament content than rabbit. Calf cells could not be maintained for longer than 21 days in the absence of ascorbate, whereas ascorbate affects the ultrastructure of rabbit cells less dramatically. Age, passage, and donor, among others, are important considerations for studying in vitro smooth muscle cells. With proper morphologic and morphometric monitoring, these smooth muscle cell culture systems can be important tools in the study of aging or pathologic processes, or both.

Animals↗
PubMed1980

Use of collagen-hydroxyethylmethacrylate hydrogels for cell growth.

Collagen-hydroxyethylmethacrylate hydrogels were prepared by polymerizing monomeric hydroxyethylmethacrylate in the presence of various concentrations of soluble native collagen. The resulting transparent hydrogels were evaluated as substrata for growth of IMR-90 human embryonic lung fibroblasts. Without collagen no significant growth occurred, whereas a dose-response curve expressing maximal cell growth against collagen concentration could be constructed quite readily by the use of appropriate hydrogels. The method allows for quantification of the collagen contribution to cell growth and, in a more general sense, provides the foundation for a relatively easy procedure to probe mechanisms of cell adhesion and cell differentiation.

Acrylic Resins↗
PubMed1979

Collagen synthesis in normal BHK cells and temperature-sensitive chemically transformed BHK cells.

Collagen synthesis in normal BHK 21/cl 13 and chemically transformed temperature sensitive BHK 21/cl 13 cells (Me2N4) was assessed by examination of hydroxyproline formation and collagenase-susceptible protein. The Me2N4 cells lost their ability to synthesize collagen at both permissive and nonpermissive temperatures for transformation. These conclusions were confirmed by polyacrylamide-gel eletrophoresis and CM-cellulose chromatography. Prolyl hydroxylase activity was present in both normal and transformed cells even when no collagen could be demonstrated. The production of noncollagen protein, although decreased in the transformed cell, did not change as drastically as the collagen synthesis.

Animals↗
PubMed1979

Failure of mechanical properties to parallel changes in lung connective tissue composition in bleomycin-induced pulmonary fibrosis in hamsters.

Lung volumes and volume pressure (V-P) relationships were measured in anesthetized hamsters 8, 30, 60, and 90 days after induction of interstitial pulmonary fibrosis by intratracheal administration of bleomycin. Subsequently, total collagen, elastin, protein, deoxyribonucleic acid (DNA), and dry weight were determined in the lungs of each animal. The mean volume of air in the lungs at a transpulmonary pressure of 25 cm H2O and mean quasi-static compliance were decreased at 8 and 30 days and had returned toward normal by 60 and 90 days. Dry lung weight and total protein content were increased at 8 days, peaked at 30 days, and were still greater than normal at 90 days; DNA peaked at 8 days, remained unchanged through day 60, and returned to normal by day 90. Collagen and elastin content, although not significantly different from control at day 8, was increased at day 30 with peak values attained at day 90. Ratios of collagen or elastin to dry weight, total protein, and DNA were decreased at 8 days, normal at 30 days, and increased at 90 days. The ratios of collagen or elastin to total protein, dry lung weight, or DNA cannot be used as indicators of the amounts of these proteins in the whole lung. We conclude that in interstitial pulmonary fibrosis induced with bleomycin the pattern of changing biochemical composition of the lungs cannot be inferred from the lung volumes or V-P relations.

Administration, Topical↗
PubMed1979

The dose-dependent fate of enzymatically active and inactivated tritiated methylated pancreatic elastase administered intratracheally in the hamster.

Hamsters were intratracheally instilled with saline solutions containing a high dose (145 to 220 micrograms) or a low dose (1.3 to 1.5 micrograms) of 3H-methylated pancreatic elastase or N-acetyl-(L-alanyl)3-L-alanine chloromethyl ketone-inactivated 3H-methylated pancreatic elastase. Only the lysyl residues of the elastase molecule were methylated and radiolabeled in a nonlabile manner. The 3H-methylated elastase preparation exhibited esterolytic and elastolytic activity, spectral properties, and emphysema-inducing properties indistinguishable from those of unmodified pancreatic elastase. There was no detectable hemorrhagic or emphysematous reaction with the inactivated 3H-methylated elastase, and this material was cleared from the lungs 11 times faster than the corresponding enzymatically active high dose of 3H-methylated elastase and 18 times faster than the corresponding enzymatically active low dose of 3H-methylated elastase. There were correspondingly higher amounts of radioactivity in the urine of hamsters treated with the inactivated elastase. All of the 3H radioactivity recovered from the urine was associated with epsilon-N-methyllysyl and epsilon-N,N-dimethyllysyl residues. Significant levels of radioactivity were found in the cells, primarily alveolar macrophages, lavaged from the lungs. The low dose of enzymatically active elastase caused neither detectable hemorrhage nor emphysema, both of which were associated with the high dose. At 144 days significant radioactivity (1,200 cpm) remained in the lungs of animals treated with high or low doses of enzymatically active elastase, whereas virtually no radioactivity (100 cpm) was found in the lungs of those treated with high or low doses of inactivated elastase. The data presented support the hypothesis that the formation of elastase complexes with alpha 1-protease inhibitor and alpha 2-macroglobulin is associated with the slower clearance and the retention of significant amounts of radioactivity in the lungs. Some of the residual radioactivity found in the hamster lungs might represent enzymatically active elastase complexed with alpha 2-macroglobulin and might offer an explanation for the progressive nature of emphysema induced by a single dose of elastase.

Animals↗
PubMed1978

Isolation of purified insoluble aortic collagen.

The chemistry of collagen from major blood vessels, such as the aorta, is poorly defined because of problems encountered in solubilization techniques. Normal extraction of calf aorta with acetic acid and/or pepsin does not yield significant quantities of collagen. However, treatment of the aorta with purified pancreatic elastase results in a residue containing a significant portion of the collagen. The amino acid analysis, the acrylamide gel electrophoretic patterns and the electron micrographs of this residue display characteristics consistent with relatively pure collagen. Using this purified collagen preparation approximately 90% of the collagenous material present can be solubilized by pepsin treatment.

Amino Acids↗
PubMed1978

A modified procedure for the purification of clostridial collagenase.

A method is described for the purification of clostridial collagenase from a crude enzyme preparation employing cation exchange chromatography on SP Sephadex, anion exchange chromatography on DEAE cellulose and gel filtration on Sephacryl S-200. Emphasis was placed on purity using continuous shallow gradients for the ion exchange separations to increase resolution and monitoring eluates both with respect to ultraviolet light absorption at 230 nm and analytical disc gel acrylamide electrophoresis. In addition, protein fractions were assayed for collagenolytic and non-specific proteolytic activity. The purity of the final preparation was assessed by acrylamide electrophoresis, gel filtration and amino acid analysis. The isolated enzyme hydrolyzed between 30 and 40% of rat tail tendon collagen in 1 h at 37 degrees C and lacked measurable trypsin or elastase-like activity.

Amino Acids↗
PubMed1978

The fate of newly synthesized lung collagen after endotracheal administration of C-proline to hamsters.

The endotracheal administration of 14C-proline to young adult golden hamsters was effective in radiolabeling collagen and resulted in a greater specific activity for hydroxyproline than did intraperitoneal administration of the amino acid. The isolation of purified isoluble collagen was accomplished with the aid of pancreatic elastase. Enzyme treatment of lung homogenates resulted in the solubilization of 35 per cent of total lung collagen. The residue obtained after elastase treatment was pure collagen. A significant portion of the radiolabeled collagen was solubilized by the elastase treatment, which suggests that elastase may be helpful in distinguishing between newly synthesized and total lung collagen. Studies performed at various times after administration of 14C-proline indicate that a greater portion of the collagen radioactivity is solubilized during the early days after treatment with the amino acid. The methodology and procedures outlined in this communication allow for additional insights into the metabolism of connective tissue, specifically collagen, in normal and diseased lungs.

Animals↗