Structural Changes in the Deoxyribonucleoprotein (DNP) Complex of Leukocytes from Patients with Infectious Mononucleosis

Abstract Quantitative microfluorimetric measurements on individual acridine orange (AO) stained cells showed that leukocytes from patients with infectious mononucleosis (IM) exhibited considerably greater AO binding to deoxyribonucleoprotein (DNP) than leukocytes from healthy persons. The higher binding of AO could not be explained by an increase in the amount of DNP in IM cells but by an increased number of binding sites in DNP accessible to AO. This was the result of structural changes in the DNP complex of the IM cells, possibly due to weakened bonds between the DNA and protein moieties of DNP. The binding of AO to IM leukocytes was highest in the early phase of the disease and usually normalized after recovery. However, an increased AO binding of leukocytes from patients after recovery was frequently observed when these cells were exposed to plasma from patients in the acute phase of IM.

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The Estimation of the Number of Binding Sites for Antibody on Antigen Molecules with Reference to Factor VIII and its Antibody

Thrombosis and Haemostasis ◽

10.1055/s-0038-1647956 ◽

1976 ◽

Vol 35 (02) ◽

pp. 274-288 ◽

Cited By ~ 2

Author(s):

Judith Pool ◽

Rosemary Biggs ◽

R. G Miller

Keyword(s):

Factor Viii ◽

Binding Sites ◽

Theoretical Basis ◽

Human Antibody ◽

Rabbit Antibody ◽

Number Of Binding Sites ◽

Theoretical Considerations

SummaryThe theoretical basis for determining the number of antibody sites on antigen molecules is examined. The theoretical considerations are applied to factor VIII molecules. Examples based on data available at the Oxford Haemophilia Centre are calculated to illustrate the approach. It is concluded that there are few sites on each factor VIII molecule for human antibody. The three antibodies for which reasonable data were available suggest 1–3 sites for human antibody. The data for rabbit antibody suggest 5–6 sites per factor VIII molecule.

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Abnormal Platelet Serotonin Uptake and Binding Sites in Myeloproliferative Disorders

Thrombosis and Haemostasis ◽

10.1055/s-0038-1661099 ◽

1984 ◽

Vol 51 (03) ◽

pp. 349-353 ◽

Cited By ~ 9

Author(s):

C Caranobe ◽

P Sié ◽

F Fernandez ◽

J Pris ◽

S Moatti ◽

...

Keyword(s):

Binding Sites ◽

High Capacity ◽

Specific Inhibitor ◽

Myeloproliferative Disorders ◽

Normal Subjects ◽

Binding Data ◽

Full Explanation ◽

Number Of Binding Sites ◽

5 Ht Uptake ◽

Kinetics Of

SummaryA simultaneous investigation of the kinetics of serotonin (5 HT) uptake and of binding sites was carried out in the platelets of normal subjects and of 10 patients affected with various types of myeloproliferative disorders (MD). The 5 HT uptake was analysed according to the Lineweaver-Burk and the Eadie-Hofstee methods. With the two methods, the patient’s platelets exhibited a dramatic reduction of the Vi max and of the Km; in some patients the Eadie-Hofstee analysis revealed that a passive diffusion phenomenon is superimposed on the active 5 HT uptake at least for the higher concentration used. The binding data were analysed with the Scatchard method. Two classes of binding sites (high affinity - low capacity, low affinity - high capacity) were found in normal subjects and patients. Pharmacological studies with imipramine, a specific inhibitor of 5 HT uptake, suggested that both the sites are involved in 5 HT uptake. The number of both binding sites was significantly decreased in patient’s platelets while the affinity constants of these binding sites were not significantly reduced in comparison with those of the control subjects. No correlations were found between Vi max, Km and the number of binding sites. These results suggest that a reduction in the number of platelet membrane acceptors for 5 HT commonly occurs in myeloproliferative disorders but does not provide a full explanation of the uptake defect.

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Intimal thickening and disruption of the media occur in the arterial walls of coronary arteries not associated with coronary arterial aneurysms in patients with Kawasaki disease

BMC Cardiovascular Disorders ◽

10.1186/s12872-021-02090-7 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Tomoya Tsuchihashi ◽

Nobuyuki Kakimoto ◽

Takashi Takeuchi ◽

Tomohiro Suenaga ◽

Takayuki Suzuki ◽

...

Keyword(s):

Kawasaki Disease ◽

Acute Phase ◽

Coronary Arteries ◽

Structural Changes ◽

Artery Aneurysm ◽

Intimal Thickening ◽

Structure Damage ◽

Convalescent Phase ◽

Arterial Structure ◽

The Media

Abstract Background Coronary artery aneurysm (CAA) is an important complication of Kawasaki disease (KD) that is associated with arterial structure damage. However, few studies have examined structural changes in coronary arteries that are not associated with CAA. Methods We examined coronary arteries in KD patients with CAAs who underwent follow-up coronary angiography (CAG) and optical coherence tomography (OCT). Coronary arterial branches with no abnormal findings during the most recent CAG were classified into two groups. Arteries with an acute-phase CAA that later regressed were classified as group R; arteries with no abnormal findings on either acute or convalescent phase CAG were classified as group N. Coronary arterial wall structural changes were compared between groups using OCT. Results Fifty-seven coronary arterial branches in 23 patients were evaluated by OCT. Thirty-six branches showed no abnormality during the most recent CAG. Both groups R and N comprised 18 branches. Maximum intimal thicknesses in groups R and N were 475 and 355 µm, respectively (p = 0.007). The incidences of media disruption were 100% and 67%, respectively (p = 0.02). Calcification, macrophage accumulation, and thrombus were not found in either group. Conclusions Intimal thickening and disruption of the media occur in coronary arteries with acute phase CAAs that later regress in the convalescent phase, as well as in arteries with normal CAG findings in the acute and convalescent phases.

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Secondary Structural Model of MALAT1 Becomes Unstructured in Chronic Myeloid Leukemia and Undergoes Structural Rearrangement in Cervical Cancer

Non-Coding RNA ◽

10.3390/ncrna7010006 ◽

2021 ◽

Vol 7 (1) ◽

pp. 6

Author(s):

Matthew C. Wang ◽

Phillip J. McCown ◽

Grace E. Schiefelbein ◽

Jessica A. Brown

Keyword(s):

Cervical Cancer ◽

Chronic Myeloid Leukemia ◽

Hela Cells ◽

Binding Sites ◽

Myeloid Leukemia ◽

Structural Changes ◽

Structural Model ◽

Dimethyl Sulfate ◽

K562 Cells ◽

Cancer Types

Long noncoding RNAs (lncRNAs) influence cellular function through binding events that often depend on the lncRNA secondary structure. One such lncRNA, metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), is upregulated in many cancer types and has a myriad of protein- and miRNA-binding sites. Recently, a secondary structural model of MALAT1 in noncancerous cells was proposed to form 194 hairpins and 13 pseudoknots. That study postulated that, in cancer cells, the MALAT1 structure likely varies, thereby influencing cancer progression. This work analyzes how that structural model is expected to change in K562 cells, which originated from a patient with chronic myeloid leukemia (CML), and in HeLa cells, which originated from a patient with cervical cancer. Dimethyl sulfate-sequencing (DMS-Seq) data from K562 cells and psoralen analysis of RNA interactions and structure (PARIS) data from HeLa cells were compared to the working structural model of MALAT1 in noncancerous cells to identify sites that likely undergo structural alterations. MALAT1 in K562 cells is predicted to become more unstructured, with almost 60% of examined hairpins in noncancerous cells losing at least half of their base pairings. Conversely, MALAT1 in HeLa cells is predicted to largely maintain its structure, undergoing 18 novel structural rearrangements. Moreover, 50 validated miRNA-binding sites are affected by putative secondary structural changes in both cancer types, such as miR-217 in K562 cells and miR-20a in HeLa cells. Structural changes unique to K562 cells and HeLa cells provide new mechanistic leads into how the structure of MALAT1 may mediate cancer in a cell-type specific manner.

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Effects of cations on binding of human choriogonadotropin

Biochemistry and Cell Biology ◽

10.1139/o88-145 ◽

1988 ◽

Vol 66 (12) ◽

pp. 1258-1264

Author(s):

Patrick J. McIlroy

Keyword(s):

Binding Sites ◽

Regulatory Protein ◽

Guanine Nucleotides ◽

Guanine Nucleotide ◽

Human Choriogonadotropin ◽

Receptor Sites ◽

Number Of Binding Sites ◽

Receptor Number ◽

Guanine Nucleotide Regulatory Protein ◽

Low Ionic Strength

The effect of various salts on the binding of human choriogonadotropin to rat luteal membranes has been examined. Increasing salt concentrations had biphasic effects, initially increasing binding, then decreasing it. With NaCl, these effects were on both the affinity and the number of receptor sites. The affinity increased with increasing NaCl concentrations, to a maximum at 40 mM, and then decreased. Above 40 mM NaCl, the number of binding sites increased. NaCl also altered the effects of Mg2+ and guanyl nucleotides. At low ionic strength, Mg2+ was necessary to observe binding. Guanine nucleotides modulated this binding by decreasing the affinity. At 40 mM NaCl, Mg2+ increased receptor number without altering affinity. Guanyl nucleotides modulated this binding by reducing the number of sites to that observed in the absence of Mg2+. At 150 mM NaCl, Mg2+ and guanine nucleotides had no effect. The results suggest the presence of two pools of human choriogonadotropin receptor in rat corpus luteum, one coupled to the guanine nucleotide regulatory protein (Ns) and being Mg2+ dependent and guanine nucleotide sensitive, and the other not coupled to Ns and being Mg2+ independent and guanine nucleotide insensitive.

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Studies on synthetic peptides that bind to fibrinogen and prevent fibrin polymerization. Structural requirements, number of binding sites, and species differences

Biochemistry ◽

10.1021/bi00546a028 ◽

1980 ◽

Vol 19 (5) ◽

pp. 1013-1019 ◽

Cited By ~ 195

Author(s):

Andrew P. Laudano ◽

Russell F. Doolittle

Keyword(s):

Binding Sites ◽

Synthetic Peptides ◽

Species Differences ◽

Structural Requirements ◽

Fibrin Polymerization ◽

Number Of Binding Sites

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Somatostatin levels and binding in duodenal mucosa of rabbits with ligation of the pancreatic duct

Journal of Endocrinology ◽

10.1677/joe.0.1180227 ◽

1988 ◽

Vol 118 (2) ◽

pp. 227-232 ◽

Cited By ~ 2

Author(s):

L. G. Guijarro ◽

E. Arilla

Keyword(s):

Pancreatic Duct ◽

Binding Sites ◽

Exocrine Pancreas ◽

Duodenal Mucosa ◽

Physiological Significance ◽

Scatchard Analysis ◽

Pancreatic Duct Ligation ◽

Parallel Increase ◽

Duct Ligation ◽

Number Of Binding Sites

ABSTRACT Atrophy of the exocrine pancreas was induced in rabbits by pancreatic duct ligation. Somatostatin concentration and binding in cytosol from rabbit duodenal mucosa were studied after 6 and 14 weeks of pancreatic duct ligation. Somatostatin-like immunoreactivity was significantly increased in the duodenal mucosa in both periods. Scatchard analysis showed a parallel increase in the number of binding sites rather than a change in their affinity. The physiological significance of these findings remains to be clarified. J. Endocr. (1988) 118, 227–232

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How the sialylation level of serum N-acetyl-β-D-glucosaminidase a form in type 1 diabetes mellitus influences its activity?

Journal of the Serbian Chemical Society ◽

10.2298/jsc140430076j ◽

2014 ◽

Vol 79 (12) ◽

pp. 1491-1503

Author(s):

Vesna Jovanovic ◽

Jelena Acimovic ◽

Vesna Dimitrijevic-Sreckovic ◽

Ljuba Mandic

Keyword(s):

Diabetes Mellitus ◽

Type 1 Diabetes ◽

Type 1 Diabetes Mellitus ◽

Structural Changes ◽

Negative Charge ◽

Total Serum ◽

Secondary Complications ◽

Isoenzyme Patterns ◽

Healthy Persons

It has been verified that serum N-acetyl-?-D-glucosaminidase (NAG) activity is elevated in diabetes, but there are no reports about changes of the sialic acid (SA) content in the carbohydrate parts of NAG A form and its influence on total NAG activity changes in type 1 diabetes mellitus patients without and with secondary complications. NAG A forms were isolated, purified and characterized from the serum of 81 IDDM patients with and without secondary complications (retinopathy, polyneuropathy and nephropathy) and 25 healthy persons. The content of ?-2,6-bound SA and isoenzyme patterns of purified A form, total NAG and A form activities were determined. In all diabetic groups, A form sialylation levels were 2-3.5 times lower compared to control, while their acidities (fractions with pI 4.25-5.1) increased, particularly with progression of secondary complications. Total serum NAG activities and percentages of A form were significantly higher (P<0.001) in all diabetic groups and negatively correlated with the ?-2,6-bound SA content of the A form. In addition, they decreased as secondary diabetic complications became more complex. Observed changes could be the consequence of structural changes in the A form due to significant increase in its acidity, i.e. negative charge which originate from groups other than SA.

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