Cell Membranes Of Patients Research Articles

Cation transport function of cell membranes in patients with essential hypertension and ischemic heart disease

Cation transport function of cell membranes in patients with essential hypertension and ischemic heart disease

In vitro proteolysis of the red cell membrane in patients with HIV infection.

It has been suggested that acquired abnormalities of the red cell membrane due to various injuries [azidothymidine (AZT) therapy, immunoglobulin coating of red cells, differentiation abnormalities of erythroid precursors] contribute to the onset of anaemia in HIV-infected patients. In vitro proteolysis of erythrocyte membrane proteins is regarded as a molecular marker of membrane damage induced in vivo by different agents. We therefore investigated in vitro proteolysis of ghosts derived from red blood cells of 30 HIV-infected patients. Considered collectively, there was no significant increase in in vitro proteolysis in ghosts from anaemic HIV patients. However, a significantly higher degree of in vitro self-digestion of RBC membrane proteins was evident in HIV-infected patients with spleen enlargement, but not in splenomegalic patients suffering from liver cirrhosis. Neither AZT therapy nor the presence of a positive direct antiglobulin test seemed to be directly associated with increased in vitro protein breakdown. The results seem to suggest damage of the red cell membrane in HIV infection, induced by injuries on red cells during their prolonged retention inside an enlarged spleen, while it seems unlikely that AZT therapy or immunoglobulin coating of red cells play major roles in red cell damage.

Reduction of beta-adrenergic receptors in atrial cell membranes of patients following mild to moderate heart failure.

The density of cardiac beta-adrenoceptors (Bmax) was measured in eighteen patients [2 with atrial septal defect (ostium secundum), 4 with aortic valve disease, 3 with mitral valve disease, 1 with aortic and mitral valve disease, 5 with a history of myocardial infarction, and 3 with angina pectoris] following mild to moderate cardiac failure. Measures were obtained by cardiac catheterization prior to cardiac surgery and also during the surgical procedures. On the basis of symptoms immediately preceding surgery, the severity of the condition in each patient was categorized as either Class I (n = 5) or Class II (n = 13) following the New York Heart Association (NYHA) functional classification system. The Bmax was measured using right atrial appendage tissue obtained during cardiac surgery. [125I]-iodocyanopindolol was used for the assay. The Bmax of atrial cell membranes in patients with NYHA class II was significantly lower than that of class I (34.1 +/- 2.5 vs 55.4 +/- 9.3 fmol/mg protein, M +/- SE, p < 0.05). Correlation coefficients between the Bmax and hemodynamic parameters measured just prior to cardiac surgery were examined, but only that between Bmax and the minimum value of the time derivative of left ventricular pressure (max negative dp/dt) was significant (r = -0.552, p < 0.05). Further study is needed to understand and clarify the relationship between Bmax and dp/dt min.

Changes of membrane phospholipid composition of human erythrocytes in hyperlipidemias. I. Increased phosphatidylcholine and reduced sphingomyelin in patients with elevated levels of triacylglycerol-rich lipoproteins

The composition of red blood cell membrane and plasma phospholipids has been analyzed in patients with hyperlipidemias. In red cells of patients with elevated levels of triacylglycerol-rich lipoproteins, phosphatidylcholine (PC) was raised and sphingomyelin (SM) reduced, resulting in a 20% increase of the membrane PC/SM ratio. In plasma phospholipids of these patients PC and SM levels were also higher and lower, respectively and the plasma PC/SM ratio was elevated by more than 50%. Close positive correlations between plasma and membrane phospholipids were obtained for PC, SM and the PC/SM ratio in normolipidemic and hyperlipidemic donors. Plasmalogen phosphatidylethanolamine (PE), a supposed endogenous protector against lipid oxidation, was reduced by about 20% in red cell membrane lipids in hyperlipidemic patients. Also plasmalogen-PE in plasma tended to be reduced in hyperlipidemic donors. Plasma HDL levels were positively related to the content of plasmalogen PE in the red cell membrane. In conclusion, there are closely related increases in PC/SM ratios in plasma and the red cell membrane in patients with elevated levels of triacylglycerol-rich lipoproteins. It is speculated that decreases in red cell membrane plasmalogen-PE in hyperlipidemic patients could be related to impaired antioxidant protection, possibly as a consequence of reductions in plasma HDL levels.

Conjunctival epithelial cells from patients with Sjögren's syndrome inappropriately express major histocompatibility complex molecules, La(SSB) antigen, and heat-shock proteins.

The La(SSB) antigen has been detected within the cytoplasm and on the membrane of conjunctival cells (CC) from patients with Sjögren's syndrome, whereas it was weakly expressed in the nucleus of normal cells. The diseased CC were shown to overproduce major histocompatibility complex (MHC) class I antigens and express MHC class II antigens. Anti-heat-shock protein monoclonal antibody bound to the cell membrane in patients but not in normal controls.

Decay‐accelerating factor (DAF) on the blood cell membranes in patients with paroxysmal nocturnal haemoglobinuria (PNH): measurement by enzyme‐linked immunosorbent assay (ELISA)

We developed a quantitative enzyme-linked immunosorbent assay (ELISA) for decay-accelerating factor (DAF) on blood cell membranes using monoclonal anti-DAF antibodies. DAF is an integral membrane protein of several blood cells. It regulates the C3 and C5 convertase of the classical and alternative pathways of complement activation. It is partially or completely deficient in the membranes of blood cells of patients with paroxysmal nocturnal haemoglobinuria (PNH). The ELISA we developed for DAF measurement indicated a reliable range of measurement from 2.25 to 11.25 ng of DAF. In particular, ELISA proved to be a technically simple method and its sensitivity was enhanced by using avidin-biotin complex. In this study, DAF levels in extracts of erythrocytes from 30 healthy donors and in extracts of PMN and platelets from 15 healthy donors were measured by ELISA. The DAF content of blood cells from eight patients with PNH and erythrocytes from 13 patients with anaemia were also measured. The DAF levels of normal erythrocytes, PMN and platelets were 3110 +/- 960, 28,000 +/- 13,900 and 3100 +/- 1370 (mean +/- SD) molecules/cell, respectively. In general, the DAF content of PNH cells was below the normal range, although it was within the normal range in some cases of PNH. The DAF levels of PNH-I and -II erythrocytes were estimated from the ratio of PNH-I, -II and -III erythrocytes. And, in four cases of PNH, the DAF levels of PNH-I erythrocytes separated by acidified serum lysis were measured by ELISA. In most cases of PNH, DAF was found to be partially deficient in PNH-I and PNH-II erythrocytes.

Activation and Suppression of T Cells in Response to Thyroid and Fat Cell Membranes in Patients with Autoimmune Thyroid Disease

Conference Abstract| December 01 1985 Activation and Suppression of T Cells in Response to Thyroid and Fat Cell Membranes in Patients with Autoimmune Thyroid Disease C.J. O'Brien; C.J. O'Brien 1Liver Unit and Dept. of Endocrinology, King's College Hospital, Denmark Hill, London SE5 Search for other works by this author on: This Site PubMed Google Scholar S. Vento; S. Vento 1Liver Unit and Dept. of Endocrinology, King's College Hospital, Denmark Hill, London SE5 Search for other works by this author on: This Site PubMed Google Scholar T. Cundy; T. Cundy 1Liver Unit and Dept. of Endocrinology, King's College Hospital, Denmark Hill, London SE5 Search for other works by this author on: This Site PubMed Google Scholar C. MacSorley; C. MacSorley 1Liver Unit and Dept. of Endocrinology, King's College Hospital, Denmark Hill, London SE5 Search for other works by this author on: This Site PubMed Google Scholar A.L.W.F. Eddleston; A.L.W.F. Eddleston 1Liver Unit and Dept. of Endocrinology, King's College Hospital, Denmark Hill, London SE5 Search for other works by this author on: This Site PubMed Google Scholar R. Williams R. Williams 1Liver Unit and Dept. of Endocrinology, King's College Hospital, Denmark Hill, London SE5 Search for other works by this author on: This Site PubMed Google Scholar Clin Sci (Lond) (1985) 69 (s12): 23P. https://doi.org/10.1042/cs069023P Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Facebook Twitter LinkedIn MailTo Cite Icon Cite Get Permissions Citation C.J. O'Brien, S. Vento, T. Cundy, C. MacSorley, A.L.W.F. Eddleston, R. Williams; Activation and Suppression of T Cells in Response to Thyroid and Fat Cell Membranes in Patients with Autoimmune Thyroid Disease. Clin Sci (Lond) 1 December 1985; 69 (s12): 23P. doi: https://doi.org/10.1042/cs069023P Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentAll JournalsClinical Science Search Advanced Search This content is only available as a PDF. © 1985 The Biochemical Society and the Medical Research Society1985 Article PDF first page preview Close Modal You do not currently have access to this content.

1173 14C-GLYCINE UPTAKE BY FIBROBLASTS IN CHILDREN WITH NONKETOTIC HYPERGLYCINEMIA

In the attempt to uncover underlying pathogenetic factors that bring about the biochemical aberration and the clinical symptoms observed in patients with nonketotic hyperglycinemia, investigations of glycine transport in diploid fibroblasts of children with this syndrome were initiated. Skin fibroblasts from two nonketotic hyperglycinemic cell lines and from three normal cell lines were cultured in Eagle's medium. Amino acid transport measurements were made with cells grown on sterile glass cover-slips according to the method by Foster and Pardee. The rate of 14C-glycine uptake by fibroblasts from nonketotic hyperglycinemic patients did not differ from that of the control cell lines during the first part (30 min.) of the experiment, yet subsequently the rate of 14C-glycine uptake decreased gradually in nonketotic hyperglycinemic cells. The results of this study are in support of the hypothesis that glycine transport across cell membranes in patients with nonketotic hyperglycinemia is similar to the transport by the A system of other mammalian cell lines. Therefore, we do not consider the biochemical pertubation and the clinical course in nonketotic hyperglycinemia to be caused by a primary membrane transport defect.

Detection of liver IgG Fc receptors using soluble immune complexes of peroxidase-antiperoxidase. I. Detection in liver tissue from patients with liver diseases.

The presence of liver IgG Fc receptor sites was demonstrated in the liver tissue from 23 patients with liver diseases and 2 patients without liver lesions by the localization of soluble immune complexes of peroxidase-antiperoxidase (PAP). Cryostat sections of liver tissues were incubated with the complexes and the peroxidase activity was revealed histochemically. In the normal liver tissue, PAP were localized on the liver cell membrane, the Kupffer cells, and some of the sinusoidal walls. In acute hepatitis, a strongly positive reaction on swollen Kupffer cells was remarkable but positive reaction on the liver cell membrane was very weak. In chronic aggressive hepatitis, PAP were strongly positive on multiplied Kupffer cells and many PAP-positive infiltrated cells were observed at the area of piecemeal necrosis. However, the positive reaction on the liver cell membrane in patients with chronic aggressive hepatitis was generally fainter than in the normal cases without liver diseases. These results correlated well with the severity of liver cell necrosis. In chronic persistent hepatitis, the number of PAP-positive infiltrated cells in the portal area and positive Kupffer cells were fewer than in chronic aggressive hepatitis. Similar results were obtained with liver cirrhosis, and in particular, the liver cell membrane with regenerative nodules gave a positive reaction. A negative result was obtained by incubation with PAP-F(ab')2 alone. PAP reaction was significantly inhibited by pretreatment with aggregated human IgG, trypsin, and pronase but not with neuraminidase.

Damage to cytoplasmic membranes in patients with acute myocardial infarction

The dependence of damage to the outer cell membranes in patients with acute myocardial infarction on the characteristics of the fractional distribution of cholesterol was studied. Determination of 5-nucleotidase activity is an objective criterion for assessing damage to the outer cell membranes, which can be considered a risk factor for thrombus formation and progression of coronary heart disease.

Adenylate cyclase and atpase activities in red cell membranes of patients and genetic carriers of duchenne muscular dystrophy

Basal adenylate cyclase activity was increased in red cell ghosts from both patients with Duchenne muscular dystrophy and their mothers when the activities were compared to proper age-matched controls. The activity of ATPase measured in the presence of Na+, K+, and Mg2+ was not found to be different in erythrocyte ghosts from Duchenne dystrophic patients, age-matched controls, or the mothers of Duchenne patients, and ouabain inhibited ATPase in ghosts to the same extent in all membrane preparations.

Carbohydrate content of human red cell membrane in patients with cirrhosis of the liver

The protein and carbohydrate contents of red cell membranes from 12 patients with liver cirrhosis were compared to those from 12 normal donors. Protein content was significantly higher and surface sialic acid and neutral hexoses were similar, whereas surface fucose and hexosamine were significantly lower in the cirrhotic red cells. The role of these membrane modifications is discussed.

Studies of red cell stromal proteins in Tay-Sachs disease.

Hemoglobin-free red blood cell ghosts of nine patients with Tay-Sachs disease and 14 normal control subjects have been analyzed for content of total protein, hexosamines, individual amino acids, and sialic acid. Red cell ghosts from Tay-Sachs' children have been shown to contain significantly increased amounts of protein, hexosamine, threonine, and serine, and probably sialic acid, each of which was increased by approximately 25% over control values. These observations suggest that the red cell membrane in patients with Tay-Sachs disease contains a significant excess of a glycoprotein or proteins, as compared with normal, and that the metabolic defect in this disease, therefore, affects glycoproteins as well as complex lipids.