Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0002895 (sickle cell disease)
 11,747 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cell adhesion and spreading were studied on sulphonated polystyrene dishes in serum-free saline (Mn, Na, Cl, buffer) i.e., without an intervening protein layer. Spreading as a function of surface charge density, SCD, peaked around 2-10 negative charges per square nanometer, corresponding to a monomolecular layer of sulphonate ions. At optimal SCD, macrophages, BHK-C13 and whole mouse embryo secondary cells all showed considerable spreading, even in monovalent saline-more so than on a conventional tissue-culture surface. But outside this narrow range of SCD, or on protein-coated surfaces, the divalent cation was indispensable. The biphasic effect of sulphonation on cell adhesion is consistent with the theory that a substratum need not be biochemically specific, provided it is physiochemically polar, rigid and dense. According to this theory, polystyrene of sub-optimal SCD would not be sufficiently polar, while supra-optimal sulphonation would produce a hydrogel surface, lacking in local rigidity and density, due to osmotic swelling. The principle of polymer exclusion, by a surface hydrogel layer, is also consistent with observations on the inhibitory effects of adsorbed proteins-viz., albumin, collagen, serum and cellular exudate, respectively-contrasted with the ready attachment of cells to a bare, optimally charged substratum, in this minimal in vitro system.
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PMID:Sulphonated polystyrene as an optimal substratum for the adhesion and spreading of mesenchymal cells in monovalent and divalent saline solutions. 40 1

The activity of deoxythymidine kinase was assayed in implanted sponge connective tissue in three groups of subjects: 1) five normal controls (having normal levels of plasma and red cell zinc); 2) four patients with sickle cell anemia who had low zinc in red cells and hair; and 3) two volunteers (under strict dietary controls), after 6 mo of zinc restriction (2.7 mg/day) and repeated after 3 mo of zinc repletion (30 mg/day). Total protein, total collagen, RNA/DNA, and deoxythymidine kinase activity were measured by techniques reported previously. In sickle cell anemia patients, deoxythymidine kinase activity was not detected, and RNA/DNA, total collagen, and total protein contents were decreased compared to normal controls (statistically significant). In human volunteers deoxythymidine kinase activity was not detected during the zinc restriction phase. After supplementation with zinc, deoxythymidine kinase activity became 70% of normal control levels, and RNA/DNA, total collagen, and total protein contents of sponge connective tissue increased. In conclusion, an adverse effect of zinc deficiency on deoxythymidine kinase activity of implanted sponge connective tissue of man has been demonstrated for the first time.
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PMID:Deoxythymidine kinase activity of human implanted sponge connective tissue in zinc deficiency. 42 58

Because of the high prevalence of thrombotic complications in patients with sickle cell anemia (SCA), we investigated platelet function in patients with sickle hemoglobinopathies. Platelet aggregation induced by epinephrine, ADP, and collagen, except for absent secondary wave in 3 of 10 patients with SCA, was qualitatively normal. However, ristocetin-induced platelet aggregation (RIPA) with a final concentration 1.12 mg/ml was markedly abnormal-absent or virtually absent in 9 of 10 patients with SCA, 3 of 3 patients with hemoglobin S-C disease, and 2 of 3 patients with sickle trait. All 8 controls used in these experiments repeatedly demonstrated normal RIPA. Addition of normal plasma failed to correct abnormal RIPA in sickle hemoglobinopathy patients. All patients demonstrated normal RIPA with a ristocetin dose of 2.24 mg/ml and aggregated with bovine fibrinogen. Recombinant mixing experiments demonstrated that washed SCA platelets support RIPA (1.12 mg/ml) when resuspended in normal plasma or high dilutions of SCA plasma, but not in undiluted SCA plasma. Washed normal platelets do not support RIPA (1.12 mg/ml) when resuspended in SCA plasma. These findings suggest the presence of a plasma inhibitor of RIPA in patients with sickle hemoglobinopathies.
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PMID:A plasma inhibitor of ristocetin-induced platelet aggregation in patients with sickle hemoglobinopathies. 59 69

Painful crises in sickle cell anemia are associated with infarction and subsequent fibrosis of many different organs. Myonecrosis secondary to muscle infarction during a crisis and subsequent fibrosis are often not recognized as complications of sickle cell anemia. We describe four patients, all of whom had recurrent episodes of symmetric proximal muscle pain and swelling as prominent features of their crises. Muscle biopsies showed acute myonecrosis with a minimal inflammatory reaction as well as myofibrosis with abundant collagen deposition. Chronic sequelae consisted of muscle induration, atrophy, and contractures.
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PMID:Myonecrosis and myofibrosis as complications of sickle cell anemia. 192 31

Chronic leg ulcers in sickle cell anemia occur mainly around the ankles. The prevalence is up to 75% in adults. These ulcers are painful and debilitating, yet medical treatment is unsuccessful. Surgical treatment consists of repeated skin grafting procedures, which eventually deplete the patient's available donor sites. Thus, in vitro generation of human epidermal autograft for potential treatment of leg ulcers in sickle cell anemia was initiated. However, because epidermal cells need a supporting matrix in order to be applied to the ulcer, the authors decided to assess the independent effect of a collagen matrix alone in promoting healing of sickle cell leg ulcers. Collistat (Hellistex, Inc) dressing was applied directly to the ulcers. The ulcers were reviewed every 2 weeks, and the dressing reapplied every 4 weeks. Collagen matrix caused the chronic ulcers to heal completely in fewer than 3 months. This encouraging performance of collagen alone should be greatly enhanced by the in vitro epidermal autograft.
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PMID:Rapid healing of sickle cell leg ulcers treated with collagen dressing. 276 90

Serum immunoreactive prolyl hydroxylase protein, galactosylhydroxylysyl glucosyltransferase activity and the aminoterminal propeptide of type III procollagen were measured in 20 patients with sickle cell disease and the values were compared with those in 20 apparently healthy Nigerians. The means for the two enzymes and serum aminoterminal propeptide of type III procollagen were significantly higher in the sickle cell disease patients. Significant correlations were found between the values for the two enzymes and the protein serum aminoterminal propeptide of type III procollagen within the sickle cell disease patients. The data confirm that collagen formation is found in the liver, bone and other organs of patients with this disease. The measurement of serum immunoreactive prolyl hydroxylase protein, serum galactosylhydroxylysyl glucosyltransferase activity and serum aminoterminal propeptide of type III procollagen in prospective studies might be helpful in predicting hepatic, bone or diffuse fibrogenesis in sickle cell disease.
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PMID:Serum enzymes of collagen synthesis and type III procollagen amino-propeptide in Nigerian patients with sickle cell disease. 301 43

Serum immunoreactive prolyl hydroxylase protein (S-IRPH), galactosylhydroxylysyl glucosyltransferase activity (S-GGT), and the aminoterminal propeptide of type III procollagen (S-Pro(III)-N-P) were measured in 20 patients with sickle cell disease and the values were compared with those in 20 apparently healthy Nigerians. The means for the two enzymes and S-Pro(III)-N-P were significantly elevated in the sickle cell disease patients. Significant correlations were found between the values of the two enzymes and the protein (S-Pro(III)-N-P) within the sickle cell disease patients. The data confirm that collagen formation is found in the bone, liver, or other organs of patients with this disease. The measurement of S-GGT and S-Pro(III)-N-P in prospective studies might be helpful in predicting general and hepatic fibrogenesis in sickle cell disease.
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PMID:Serum enzymes of collagen synthesis and type III procollagen aminopropeptide in Nigerian patients with sickle cell disease. 301 72

Measurements of the coagulation system were carried out in children with sickle cell disease (SCD) in both steady state and on the 1st day of painful crisis and were compared to age- and sex-matched healthy controls. No significant differences were found in prothrombin time, partial thromboplastin time, thrombin time, reptilase time, plasma fibrinogen, antithrombin III, factor VIII:C, ristocetin-cofactor (Ri-Cof) and platelet aggregation responses to ADP, collagen and adrenaline. Abnormal aggregation responses to ristocetin were noted in all patients with SCD when compared to controls. Daily measurements during the first 4 days of painful crisis showed significant elevation of fibrinogen and Ri-Cof and enhancement of aggregation to ADP and adrenaline by the 3rd day of crisis. It was concluded that the changes noted, rather than being primarily responsible for the onset of crisis, can only be secondary changes arising from the aetiological factors of crisis, i.e. stasis and acute-phase proteins.
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PMID:Coagulation changes in sickle cell disease in early childhood. 311 56

Ticlopidine is an inhibitor of platelet action that has been used in the treatment of a variety of disease states in which platelets play a prominent role. Studies in animals and man have demonstrated that ticlopidine is a potent inhibitor of platelet aggregation induced by adenosine diphosphate (ADP), and variably inhibits aggregation due to collagen, adrenaline (epinephrine), arachidonic acid, thrombin, and platelet activating factor. Inhibition of platelet aggregation is both dose- and time-related, with its onset of activity being 24 to 48 hours, its maximal activity occurring after 3 to 5 days, and its activity still being present 72 hours after a final dose. Ticlopidine also inhibits the release reaction of platelets, prolongs bleeding time, reduces plasma levels of platelet factor 4 and beta-thromboglobulin in patients in whom these proteins are elevated, and may also inhibit platelet adhesion, increase red cell filtrability and decrease whole blood viscosity. In a large number of animal models, ticlopidine markedly inhibits thrombus formation or graft occlusion. Ticlopidine is well absorbed after oral administration. It is extensively metabolised and at least one of its metabolites is pharmacologically active. Therapeutic trials in patients with chronic arterial occlusion due to thrombangitis obliterans or arteriosclerosis obliterans, post-myocardial infarction, cerebrovascular thromboembolic disease, subarachnoid haemorrhage, vascular shunts or fistulas for haemodialysis, and sickle cell disease have shown promise for the use of ticlopidine. However, trials of patients with intermittent claudication, angina pectoris, diabetes mellitus with microvascular disease, aortocoronary bypass grafts, and vascular prostheses have had conflicting results or have shown an unfavourable side effect profile. Further studies are clearly required to establish the role of ticlopidine in many of these areas, some of which are already in progress. Overall, side effects occur in 10 to 15% of patients receiving ticlopidine. The most common side effects are gastrointestinal disturbances and skin rashes. Neither of these necessarily require discontinuation of therapy in most patients. Agranulocytosis, thrombocytopenia, and cholestatic jaundice have also been reported. Bleeding is infrequent except possibly in patients receiving ticlopidine prior to some surgical procedures.
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PMID:Ticlopidine. A review of its pharmacodynamic and pharmacokinetic properties, and therapeutic efficacy in platelet-dependent disease states. 330 67

The kidney is involved in a variety of systemic diseases and conditions including collagen, endocrine, liver, infectious, neoplastic, and cardiac diseases, as well as pregnancy. Renal involvement in hematologic diseases has not been stressed. In this review we will summarize the role of coagulation in the pathophysiology of renal disease and present renal involvement in sickle cell anemia, hemolytic uremic syndrome, thrombotic thrombocytopenic purpura, leukemia, and other less common hematologic diseases.
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PMID:The kidney in hematologic disease. A review. 354 73


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