Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0267964 (PAA)
 2,561 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In order to overcome the biological deficiencies of synthetic polymers and to enhance the mechanical characteristics of natural polymers, two synthetic polymers, poly(vinyl alcohol) (PVA) and poly(acrylic acid) (PAA) were blended, in different ratios, with two biological polymers, collagen (C) and hyaluronic acid (HA). These blends were used to prepare films, sponges and hydrogels which were loaded with growth hormone (GH) to investigate their potential use as drug delivery systems. The GH release was monitored in vitro using a specific enzyme-linked immunosorbent assay. The results show that GH can be released from HA/PAA sponges and from HA/PVA and C/PVA hydrogels. The initial GH concentration used for sample loading affected the total quantity of GH released but not the pattern of release. The rate and quantity of GH released was significantly dependent on the HA or C content of the polymers.
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PMID:Blends of synthetic and natural polymers as drug delivery systems for growth hormone. 749 22

We report on a case of lethal short-limbed skeletal dysplasia with extremely short ribs, median cleft upper lip and palate, malrotation of intestine, lung hypoplasia with bilateral segmentation defect, atrial septum defect, union of distal urethra and vagina, and complex brain malformations. Based on radiological criteria and the pattern of associated abnormalities a short rib syndrome without polydactyly (Type Beemer) was diagnosed. Morphologically, the growth plate showed a reduced proliferation zone and an enlarged zone of hypertrophic cartilage. In addition, islands of persistent hypertrophic cartilage were present even in the metaphysis. In monolayer cell cultures supplemented with 10% fetal calf serum proliferation was normal in articular chondrocytes, reduced in costal chondrocytes, and elevated in osteoblasts from the patient. Clonal growth of costal and articular chondrocytes in methylcellulose could be stimulated normally by insulin-like growth factor-I (IGF-I), IGF-II, and human growth hormone (hGH). However, the response to transforming growth factor beta 1 (TGF-beta 1) was markedly elevated in articular chondrocytes of the patient compared to those of 3 fetal controls. Quantitative collagen synthesis in both osteoblasts and chondrocytes from the patient did not differ significantly from that of controls. Osteoblasts synthesized predominantly collagen I and minor amounts of collagen III, chondrocytes synthesized primarily collagen II. All collagen chains including CNBr-peptides of collagen II showed normal migration in PAA gel electrophoresis.
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PMID:Proliferation and collagen biosynthesis of osteoblasts and chondrocytes in short rib syndrome type beemer. 832 25

Bioartificial polymeric materials, based on blends of polysaccharides with synthetic polymers such as poly(vinyl alcohol) (PVA) and poly(acrylic acid) (PAA), were prepared as films or hydrogels. The physico-chemical, mechanical, and biological properties of these materials were investigated by different techniques such as differential scanning calorimetry, dynamic mechanical thermal analysis, scanning electron microscopy, and in vitro release tests, with the aim of evaluating the miscibility of the polymer blends and to establish their potential applications. The results indicate that while dextran is perfectly miscible with PAA, dextran/PVA, chitosan/PVA, starch/PVA, and gellan/PVA blends behave mainly as two-phase systems, although interactions can occur between the components. Cross-linked starch/PVA films could be employed as dialysis membranes: they showed transport properties comparable to, and in some cases better than, those of currently used commercial membranes. Hydrogels based on dextran/PVA and chitosan/PVA blends could find applications as delivery systems. They appeared able to release physiological amounts of human growth hormone, offering the possibility to modulate the release of the drug by varying the content of the biological component.
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PMID:Bioartificial polymeric materials based on polysaccharides. 1148 36