Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P00790 (PGA)
 2,475 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The possibility of preservation and restoration of antigenicity of some antigens in paraffin-embedded tissue was evaluated by direct immunofluorescent technique on deparaffinized sections. Fixation with 96% ethanol-1% acetic acid, 10% neutral buffered formalin and p-formaldehyde was useful for the preservation of tissue antigens and immune deposits, whose antigenicity could be easily restored by trypsin digestion. Neutral buffered formalin was also a satisfactory fixative in immunofluorescent staining on lymphocyte/plasma cell-bound immunoglobulins. Fixation with alcohol-Bouin's fluid showed contrast results; feasible for staining of cell-bound immunoglobulins, but poor for that of glomerular immune deposits. After papain digestion, BSA and lysozyme, antigens of immune complexes, were easily detected in experimental chronic serum sickness glomerulonephritis. Pepsin was more efficient than trypsin in restoring the antigenicity of renal tissue antigens such as fibronectin and polyantigenic basement membrane, but the brush border antigen of the proximal renal tubules was frail to the pepsin digestion. In general, the enzymatic digestion time necessary for the restoration of antigenicity was in parallel with fixation time. Results obtained have shown that deparaffinized sections could be used as satisfactory substrate for immunohistochemistry when proper fixation and efficient proteolytic enzymatic pretreatments were performed.
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PMID:Restoration of antigenicity of tissue antigens, cell-bound immunoglobulins and immune deposits in paraffin-embedded tissue. The influence of fixation and proteolytic enzymatic digestion. 643 48

Collagen was isolated by acetic acid extraction in the presence of protease inhibitors and also by pepsin digestion from the skins of dogs affected with the Ehlers-Danlos syndrome and the skins on non-affected dogs. The collagen preparations isolated by acetic acid extraction from the Ehlers-Danlos syndrome-affected dog skin contained a greater proportion of alpha-chains than the collagen preparations from the normal dog skin. When the collagen from the Ehlers-Danlos syndrome-affected dog skin was reduced with NaBH4 before heat denaturation, and electrophoresis, there was a greater proportion of beta-chains present. The collagen isolated from the normal dog skin was not affected by the NaBH4 reduction. Collagen preparations isolated by pepsin digestion from both the Ehlers-Danlos syndrome-affected dog skin and the non-affected dog skin contained the same quantity of alpha- and beta-chains. In addition, collagen from both affected and non-affected dog skins isolated by pepsin digestion contained 10-11% type III collagen as determined by the interrupted sodium dodecyl sulfate polyacrylamide gel electrophoresis method. Pepsin digestion of the collagens isolated by acetic acid extraction in the presence of protease inhibitors from the skins of affected and non-affected dogs eliminated the differences between the alpha:beta ratios of the affected and non-affected collagen preparations.
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PMID:Isolation of collagen from the skins of Ehlers-Danlos syndrome-affected dogs by acetic acid extraction and pepsin digestion. 677 75

Chronic pyelonephritis was induced in young adult cats by the intravenous injection of a human or a feline strain of Escherichia coli after ligation of one ureter for 24 or 48 h. In the 3 cats infected with the feline strain, scarred kidneys from the obstructed side were removed at necropsy 3, 4 and 5 months later. Collagen was extracted from pyelonephritic and normal kidney tissue with dilute acetic acid and limited proteolysis with pepsin. Scarred kidneys gave higher yields of both acid-soluble collagen (normal = 0.57 +/- 0.12 mg per g tissue; scarred = 0.88 +/- 0.10 mg per g tissue) and pepsin-solubilized collagen (normal = 9.69 +/- 1.79 mg per g tissue; scarred = 20.02 +/- 2.84 mg per g tissue). There was no significant increase in the collagen yield from the kidneys of the 2 cats in which mild focal lesions were found 14 and 16 months after infection with the human strain of E. coli. Pepsin released collagens were separated by fractional salt precipitation and identified by agarose gel chromatography and polyacrylamide gel electrophoresis. Normal kidney was shown to contain collagen of Types I, IV and V (AB). The Type IV collagen extracted consisted of a mixture of 4 major pepsin-resistant chains of apparent molecular weights of 150 000, 115 000, 85 000 and 60 000. The collagen extracted from scarred kidneys was predominantly Type I, only trace amounts of Type IV and V components being present. These findings suggest that basement membrane collagens of the kidney are selectively degraded during the atrophy and scarring of chronic feline pyelonephritis and are preferentially replaced by interstitial Type I collagen.
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PMID:Experimental pyelonephritis in the cat: 3. Collagen alterations in renal fibrosis. 684 96

The extracts from bovine lens capsule with acetic acid contained, after reduction, three major collagenous polypeptides with M(r) = 180k, 175k, and 160k, which were specifically immuno-stained with anti-type IV collagen polyclonal antibody. The biochemical properties of 180k and 160k polypeptides were akin and were distinct from that of 175k polypeptide [J. Biochem. (1993) 114,358-362]. In the present study, evidence that the 160k and 180k polypeptides from bovine lens capsule both originated from alpha 1(IV) was obtained on the basis of reactivity with a monoclonal antibody that recognizes alpha 1(IV) chain at the collagenous sequence contained in [KGEPGLPGRGFPGFP]. The epitope-bearing sequence was identified from the following three experiments. Pepsin-solubilized polypeptides from human placenta were purified by affinity chromatography on the antibody-coupled column and sequenced. The restriction map of the clones positively reactive with the monoclonal antibody from human placenta cDNA library was superimposed on that of human alpha 1(IV) cDNA at a specific region. Synthetic peptides corresponding to the sequence were assayed for inhibitory activity against the reaction between epitope-bearing pepsin fragments and the antibody. The 180k and 160k polypeptides showed similar intensities in protein staining as well as in immuno-staining with the monoclonal antibody. In contrast, the 175k polypeptide did not react with the monoclonal antibody, indicating that it is a genetically distinct type IV collagen chain, presumably alpha 2(IV) from its abundance. The 160k, a major type IV collagen polypeptide, is a short form of alpha 1(IV) present as a tissue form in bovine lens capsule.
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PMID:Evidence for a short form of alpha 1(IV) as a major polypeptide in bovine lens capsule. 749 Feb 74

Cryogenically frozen vegetative cells of Bacillus licheniformis 9945a derived from young mucoid colonies were used to inoculate gamma-poly(glutamate) (gamma-PGA) production media containing L-glutamate, citrate and glycerol as carbon sources. A gel permeation chromatography (GPC) method was developed to determine gamma-PGA volumetric yield and molecular weight directly using culture filtrates. For GPC volumetric yield measurements, a calibration curve was generated using purified gamma-PGA to relate the gamma-PGA GPC peak area and polymer weight. Purified gamma-PGA was characterized by elemental analysis, 1H- and 13C-NMR spectroscopy. Cultures of B. licheniformis using all three carbon sources showed the following characteristics: cell growth mainly during the first 24 h; largest gamma-PGA volumetric productivity (approximately 0.12 gl-1 h-1) between 48 and 96 h; 11 g l-1 gamma-PGA volumetric yield by 96 h; reduction (utilization) of glycerol, glutamate and citrate during a 96 h cultivation time from 80 to 45 g l-1, 18 to 10 g l-1 and 12 to approximately 1 g l-1, respectively; a decrease in pH from 7.4 to approximately 5.5 by 42 h cultivation; acetic acid secretion into the medium at a maximum level of approximately 4.5 g l-1 and detection of the metabolite 2,3-butanediol (as acetoin) as a fermentation by-product at approximately 42 h and through a 96 h cultivation period. The presence of 2,3-butanediol indicated that the level of oxygen in the medium no longer supported a fully aerobic mode of metabolism. When the medium formulation was altered by removal of either citrate, L-glutamate or glycerol in shake flask experiments where pH was not controlled, 2.3, 9.0 and 4.0 g l-1, respectively, of gamma-PGA were formed. Variation of the medium ionic strength by the addition of up to 4% (w/v) NaCl led to the formation of gamma-PGA of relatively higher molecular weight but lower volumetric yield. Studies carried out on 5-day-old B. licheniformis cultures suggested that gamma-PGA depolymerase is intracellularly located or cell-bound. Culture filtrates showed no significant gamma-PGA depolymerase activity.
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PMID:Gamma-poly(glutamic acid) formation by Bacillus licheniformis 9945a: physiological and biochemical studies. 753 73

The purpose of this study was to compare the effect of polymer foam morphology and density prior to compaction on the kinetics of isoniazid (INH) release from the final high-density extruded matrices. The feasibility of preparing low density foams of several biopolymers, including poly(L-lactide) (PLLA), poly(glycolide) (PGA), poly(DL-lactide-co-glycolide) (PLGA), poly(gamma-benzyl-L-glutamate) (PBLG), and poly(propylene fumarate) (PPF), via a lyophilization technique was investigated. Low-density foams of PLGA, PBLG, and a mixture of PLGA and PPF were successfully fabricated by lyophilization of the frozen polymer solutions either in glacial acetic acid or in benzene. The morphology of these foams depends on the polymer as well as the solvent used in the fabrication process. Thus, PLGA produces a capillary structure when lyophilized from benzene solution and a leaflet structure from glacial acetic acid, but PBLG yields a leaflet structure from benzene. Matrices were prepared by impregnating these foams with aqueous solutions of INH, removing the water by a second lyophilization, and then compressing the low-density INH containing foams by compaction and high-pressure extrusion. The resulting nonporous matrices had densities of approximately 1.30 g/cm3. In vitro kinetics were in accord with the Roseman-Higuchi diffusion model and demonstrate that release rates depend on the initial foam density, while foam structure has little influence on the release kinetics.
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PMID:Effect of polymer foam morphology and density on kinetics of in vitro controlled release of isoniazid from compressed foam matrices. 910 3

The use of high-performance liquid chromatography for the determination of folates is well documented. The methods used are based on reversed-phase chromatography with UV and/or fluorescence detection. In many instances it is difficult to reach the required detection limits and many of the methods lack specificity. High-performance liquid chromatography-mass spectrometry (LC-MS) has become a well established analytical tool in modern laboratories. It can offer superior specificity and often lower detection limits than conventional LC detection methods and thus is ideally suited to the analysis of folates. A system capable of separating the four main folates [folic acid (pteroylglutamic acid, PGA)], 5-methyltetrahydrofolic acid, terahydrofolic acid and 5- and/or 10-formyltetrahydrofolic acid [folinic acid (CHOTHF)] using LC-MS with negative ion electrospray has been developed. After optimisation, a system using a 12.5 cm x 3 mm, 3 microm Hypersil ODS column and a mobile phase of 2.5 mM acetic acid-acetonitrile (88:12, v/v) was developed which was capable of separating the four folates in under 10 min without the use of a gradient system. Extraction of the folates is by heat treatment and sample clean-up is by solid-phase extraction (C18). On column limits of confirmation are 0.6 ng for PGA and CHOTHF.
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PMID:Analysis of some folate monoglutamates by high-performance liquid chromatography-mass spectrometry. I. 1063 Aug 71

The functions of aminotelopeptide and N-terminal cross-linking of collagen I were examined. Acetic acid-soluble collagen I (ASC) was purified from neonatal bovine skin and treated with three kinds of proteases. The amino acid sequencing analysis of the N terminus showed that ASC contained a full-length aminotelopeptide. Pepsin and papain cleaved the aminotelopeptide of the alpha1 chain at the same site and the aminotelopeptide of the alpha2 chain at different sites. Proctase-treated ASC lost the whole aminotelopeptide, and the N-terminal sequence began from the tenth residue inside the triple helical region. The rates of fibril formation of pepsin-treated ASC and proctase-treated ASC were the same and were slower than that of ASC. The denaturation temperatures, monitored by CD ellipticity at 221 nm, of ASC, pepsin-treated, or papain-treated collagens were the same at 41.8 degrees C. Proctase-treated ASC showed a lower denaturation temperature of 39.9 degrees C. We also observed the morphology of the collagen fibrils under an electron microscope. The ASC fibrils were straight and thin, whereas the fibrils of pepsin-treated ASC were slightly twisted, and the fibrils from papain- and proctase-treated ASC were highly twisted and thick. When the collagen gel strength was examined by a modified method of viscosity-measurement, ASC was the strongest, followed by pepsin-treated ASC, and papain- and proctase-treated ASCs were the weakest. These results suggest that the aminotelopeptide plays important roles in fibril formation and thermal stability. In addition, the functions of intermolecular cross-linking in aminotelopeptides may contribute to the formation of fibrils in the correct staggered pattern and to strengthening the collagen gel.
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PMID:Possible involvement of aminotelopeptide in self-assembly and thermal stability of collagen I as revealed by its removal with proteases. 1085 Dec 40

To understand the reparative process of medial collateral ligament (MCL), fibrillar collagen and their relative ratios in healing MCL with anterior cruciate ligament (ACL) reconstruction were analyzed. Skeletally mature New Zealand white rabbits were subjected to a mop-end tear of MCL without repair with ACL reconstruction. Rabbits were killed 6 and 52 weeks after injury. Ligamentous tissues from the injury site and sham controls were soaked in 0.5 M acetic acid for 24 h, minced, and treated with pepsin to solubilize collagen. Pepsin solubilized about 80% of the total collagen as determined by hydroxyproline analysis of the pepsin residues. Sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis of the solubilized collagen revealed presence of fibrillar collagen types I, III, and V. Densitometric scanning of the protein bands corresponding to types I, III, and V collagen indicated that in sham controls types III and V collagen represented about 8% and 12%, respectively, of the type I collagen whereas the healed MCL ligaments at 6 weeks showed significant increase in type III and V collagen to about 19% and 24%, respectively. By 52 weeks type III collagen in the healed MCL had returned to that of sham controls while type V collagen remained elevated at approximately 18%. These data suggest that presence of type V collagen in high concentration in healing ligaments may have an influence on collagen fibril diameters seen in healed ligament and should be included in the analysis when evaluating ligament healing.
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PMID:Type V collagen is increased during rabbit medial collateral ligament healing. 1106 Dec 96

Guanidinium chloride treatment of Sepia officinalis cartilage solubilized a component that contained hydroxyproline. Electron-microscopy observation of rotary-shadowed preparations of this component revealed it to consist of rod-like units themselves consisting of filaments. Dialysis of an acetic acid solution against ATP afforded polymeric aggregates consisting of a succession of two or three thick sections showing transverse electron-opaque banding, separated by thinner sections without banding. Electrophoresis produced a main band of about 140 kDa sensitive to bacterial collagenase. After reduction with mercaptoethanol, electrophoresis afforded a 40-kDa band. Pepsin digestion resulted in additional electrophoretic bands. These data suggest the presence of a collagen in Sepia cartilage with characteristics unlike those of any known collagen.
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PMID:A new collagen from the extracellular matrix of Sepia officinalis cartilage. 1239 79


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