scholarly journals THE MOLECULAR WEIGHT OF ANTIBODIES

1937 ◽  
Vol 65 (3) ◽  
pp. 393-414 ◽  
Author(s):  
Michael Heidelberger ◽  
Kai O. Pedersen
Keyword(s):  
Molecular Weight ◽  
Molecular Species ◽  
Principal Component ◽  
The Other ◽  
Type I ◽  
Egg Albumin ◽  
Type Iii ◽  
Sedimentation Constant ◽  
Other Hand ◽  
Immune Rabbit

1. Highly purified rabbit Type III pneumococcus anticarbohydrate proved to be homogeneous in the ultracentrifuge and its sedimentation constant, 7.0·10–13, did not differ from that of the principal component of normal rabbit globulin or of immune rabbit globulin containing up to 50 per cent of anti-egg albumin. The molecular weight of antibody in the rabbit is therefore probably very close to that of the principal normal globulin component, namely, 150,000. 2. Highly purified horse Type I pneumococcus anticarbohydrate, on the other hand, was only homogeneous in the ultracentrifuge when prepared from sera stored without preservative. Its sedimentation constant, 18.4·10–13, coincided with that of the principal globulin component in most of the Felton solutions and purified antibody solutions studied. The molecular weight of pneumococcus anticarbohydrate in the horse is probably three to four times that of the principal normal globulin component. 3. The significance of the differences between pneumococcus anticarbohydrate formed in the rabbit and in the horse is discussed. 4. Results are given of ultracentrifuge studies on the molecular species in solutions of egg albumin-anti-egg albumin specific precipitates dissolved in excess egg albumin. The implications of the results are discussed.

scholarly journals Graded Rough Sets based on Neighborhood Operator Over two Different Universes and its Application

2021 ◽  
Author(s):  
Ahmed Mostafa Khalil
Keyword(s):  
Decision Making ◽  
Rough Set ◽  
Rough Sets ◽  
The Other ◽  
Type I ◽  
Type Ii ◽  
Type Iii ◽  
Other Hand ◽  
Decision Methods ◽  
Neighborhood Rough Sets

Abstract Abstract The major concern of this paper is to present the notion of rough set based on neighborhood operator on universe set, along with its properties, and examples. Then, we generalize several notions of covering rough sets to neighborhood rough sets with respect to the graded n. Further, we present some notions such as probabilistic neighborhood rough approximations of X, (Type-I / Type-II) probabilistic neighborhood rough approximations of X with error α and β, and (Type-I / Type-II) probabilistic neighborhood rough approximations of X with respect to N . The interesting properties of above notions are investigated in detail. On the other hand, we define the notion of rough set based on neighborhood operator over two different universes. Subsequently, we present some notions (Type-I / Type-II / Type-III) graded n-neighborhood rough sets and give a two approaches to decision-making problems based on the (Type-II / Type-III) grade n-neighborhood rough sets. Then, we construct the decision steps and give two algorithms of the decision methods. Also, we will give two illustrative examples to show the applicability of the rough set based on neighborhood operator over two different universes to solve the rough decision-making problems. Finally, we give a comparison between the Liu et al.’s approach and our approach.

Effect on Polymer Chain Structure Caused by the Molar Fraction of 4-Hydroxybutyrate in Poly(3-hydroxybutyrate- co -4-hydroxybutyrate)

2012 ◽  
Vol 602-604 ◽  
pp. 776-780
Author(s):  
Zhi Qiang Li ◽  
Mei Li ◽  
Wei Jia Fan
Keyword(s):  
Molecular Weight ◽  
Intrinsic Viscosity ◽  
Polymer Chain ◽  
Molar Fraction ◽  
Chain Structure ◽  
The Other ◽  
Mean Square ◽  
Polarizing Microscope ◽  
Other Hand ◽  
The Mean

Poly(3-hydroxybutyrate-co-4-hydroxybutyrate)copolymer [P(3HB-co-4HB)] is a kind of biodegradable high molecular polymer produced by bioaccumulation. Because of the good biodegradability and biocompatibility, P(3HB-co-4HB)s have attracted wide attention . At first, the intrinsic viscosity[η] in good solvent of P(3HB-co-4HB) s with varying contents of 4HB was investigated in different temperature. Second, observed the changes of crystallization gathered state caused by the varying contents of 4HB by polarizing microscope. The results show that to the P(3HB-co-4HB)s in same molecular weight, the intrinsic viscosity[η] in good solvent barely changes when the mole fractions of 4HB increase. On the other hand, the mean square end to end distances[0] of macromolecular flexible chains increase with the mole fractions of 4HB. At the same time, the states of aggregation change from spherulites to dendrites. In this investigation, we discuss the reasons of the differences in depth.

Type I Collagen Biosynthesis by Skin Fibroblasts from Patients with Idiopathic Juvenile Osteoporosis

1995 ◽  
Vol 89 (1) ◽  
pp. 69-73 ◽  
Author(s):  
Andrew E. Pocock ◽  
Martin J. O. Francis ◽  
Roger Smith
Keyword(s):  
Osteogenesis Imperfecta ◽  
Type I Collagen ◽  
The Other ◽  
Type I ◽  
Osteogenesis Imperfecta Type ◽  
Unrelated Control ◽  
Type Iii ◽  
Collagen Peptides ◽  
Idiopathic Juvenile Osteoporosis ◽  
Osteogenesis Imperfecta Type I

1. Skin fibroblast lines were cultured from nine patients who had the features of idiopathic juvenile osteoporosis, six relatives, five unrelated control subjects and three unrelated patients with osteogenesis imperfecta type I. Some patients with idiopathic juvenile osteoporosis were adults whose previous osteoporosis was in remission. Two patients with idiopathic juvenile osteoporosis were siblings and one patient with idiopathic juvenile osteoporosis had a daughter with severe osteogenesis imperfecta (type III). 2. The ratio of type III to type I collagen, synthesized by fibroblasts, was increased in two of the patients with osteogenesis imperfecta type I and in the daughter with osteogenesis imperfecta type III, but was normal in all the other patients with idiopathic juvenile osteoporosis and the other relatives. 3. Radiolabelled collagen was digested by cyanogen bromide and separated on SDS-PAGE. Unreduced collagen peptides migrated normally, except those from both the two siblings with idiopathic juvenile osteoporosis. In these two lines, abnormal migration suggested the presence of collagen I mutations. 4. The secretion of synthesized collagen by these two idiopathic juvenile osteoporosis lines and two others was reduced to only 43–45% as compared with a line from a 13-year-old control subject, which was defined as 100%. The three osteogenesis imperfecta type I lines secreted 18–37%, the other five idiopathic juvenile osteoporosis lines secreted 57–75%, the relatives (including the daughter with severe osteogenesis imperfecta) secreted 49–115% and the controls secreted 69–102%. 5. We conclude that qualitative abnormalities of type I collagen associated with a reduction in total secreted collagen synthesis may occur in a minority of patients with idiopathic juvenile osteoporosis; these patients could represent a subset of patients with this disorder.

scholarly journals Degradation of a Short-lived Glycoprotein from the Lumen of the Endoplasmic Reticulum: The Role of N-linked Glycans and the Unfolded Protein Response

1999 ◽  
Vol 10 (12) ◽  
pp. 4059-4073 ◽  
Author(s):  
Maddalena de Virgilio ◽  
Claudia Kitzmüller ◽  
Eva Schwaiger ◽  
Michael Klein ◽  
Gert Kreibich ◽  
...  
Keyword(s):  
Endoplasmic Reticulum ◽  
Unfolded Protein Response ◽  
The Other ◽  
Slow Phase ◽  
Type I ◽  
Unfolded Protein ◽  
Other Hand ◽  
The Unfolded Protein Response ◽  
Protein Response

We are studying endoplasmic reticulum–associated degradation (ERAD) with the use of a truncated variant of the type I ER transmembrane glycoprotein ribophorin I (RI). The mutant protein, RI332, containing only the N-terminal 332 amino acids of the luminal domain of RI, has been shown to interact with calnexin and to be a substrate for the ubiquitin-proteasome pathway. When RI332 was expressed in HeLa cells, it was degraded with biphasic kinetics; an initial, slow phase of ∼45 min was followed by a second phase of threefold accelerated degradation. On the other hand, the kinetics of degradation of a form of RI332 in which the single used N-glycosylation consensus site had been removed (RI332-Thr) was monophasic and rapid, implying a role of the N-linked glycan in the first proteolytic phase. RI332degradation was enhanced when the binding of glycoproteins to calnexin was prevented. Moreover, the truncated glycoprotein interacted with calnexin preferentially during the first proteolytic phase, which strongly suggests that binding of RI332 to the lectin-like protein may result in the slow, initial phase of degradation. Additionally, mannose trimming appears to be required for efficient proteolysis of RI332. After treatment of cells with the inhibitor of N-glycosylation, tunicamycin, destruction of the truncated RI variants was severely inhibited; likewise, in cells preincubated with the calcium ionophore A23187, both RI332 and RI332-Thr were stabilized, despite the presence or absence of the N-linked glycan. On the other hand, both drugs are known to trigger the unfolded protein response (UPR), resulting in the induction of BiP and other ER-resident proteins. Indeed, only in drug-treated cells could an interaction between BiP and RI332 and RI332-Thr be detected. Induction of BiP was also evident after overexpression of murine Ire1, an ER transmembrane kinase known to play a central role in the UPR pathway; at the same time, stabilization of RI332 was observed. Together, these results suggest that binding of the substrate proteins to UPR-induced chaperones affects their half lives.

Electrophysiological Characteristics of Classes of Neuron in the HVc of the Zebra Finch

1998 ◽  
Vol 80 (2) ◽  
pp. 914-923 ◽  
Author(s):  
Michinori Kubota ◽  
Ikuo Taniguchi
Keyword(s):  
Action Potential ◽  
Zebra Finch ◽  
Action Potential Duration ◽  
The Other ◽  
Time Dependent ◽  
Inward Rectification ◽  
Type I ◽  
Type Ii ◽  
Type Iii ◽  
Type Iv

Kubota, Michinori and Ikuo Taniguchi. Electrophysiological characteristics of classes of neuron in the HVc of the zebra finch. J. Neurophysiol. 80: 914–923, 1998. Whole cell recordings were made from zebra finch HVc neurons in slice preparations. Four distinct classes of neuron were found on the basis of their electrophysiological properties. The morphological characteristics of some of these neurons were also examined by intracellular injection of Lucifer yellow. Type I neurons (21 of 65 cells) had longer time-to-peak of an afterhyperpolarization following an action potential than the other classes. They exhibited both fast and time-dependent inward rectification and an initial high-frequency firing followed by a slower constant firing. Type I neurons had large somata and thick dendrites with many spines. The axons of some of the neurons in this class projected in the direction of area X of the parolfactory lobe. Type II neurons (30 of 65 cells) had a more negative resting membrane potential than the other classes. They exhibited fast inward rectification. Type II neurons could be divided into two subclasses by the absence (IIa; 22 cells) and the presence (IIb; 8 cells) of a low-threshold transient depolarization. Type IIa neurons had relatively small somata and thin, spiny dendrites. The axons of some of the neurons in this class projected in the direction of the robust nucleus of the archistriatum (RA). Type IIb neurons had relatively large somata and thick dendrites with many spines. Type III neurons (6 of 65 cells) had a shorter action-potential duration than the other classes. They exhibited prominent time-dependent inward rectification and a regular tonic firing with little or no accommodation. Type III neurons had beaded, aspiny dendrites. Type IV neurons (8 of 65 cells) had a longer action-potential duration, a much larger input resistance, and longer membrane time constant than the other classes. Type IV neurons had small somata and thin, short, sparsely spiny dendrites. The axons of some of the neurons in this class projected in the direction of the RA. These classes of neuron may play distinct roles in song production and representation in the HVc.

FURTHER STUDIES ON THE PURIFICATION OF THROMBIN

1958 ◽  
Vol 36 (1) ◽  
pp. 603-611 ◽  
Author(s):  
Walter H. Seegers ◽  
Walter G. Levine ◽  
Robert S. Shepard
Keyword(s):  
Molecular Weight ◽  
Phosphate Buffer ◽  
Esterase Activity ◽  
Room Temperature ◽  
Specific Activity ◽  
Dry Weight ◽  
The Other ◽  
Resin Column ◽  
Sedimentation Constant ◽  
Single Symmetrical Peak

Purified biothrombin (bovine) was fractionated with the use of amberlite IRC-50 columns to obtain resin thrombin with an activity of 4100 units/mg. dry weight or 45,000 units/mg. tyrosine. As obtained from a resin column in 0.3 M phosphate buffer, pH 8.0, the thrombin is stable for 5 days at room temperature. At 4 °C. about 70% of the activity remains after 20 weeks. The maximum molecular weight is estimated by comparing with the specific activity (2000 units/mg.) and molecular weight (62,700) of purified prothrombin as follows: 2000/4100 × 62,700 or 30,600 as the probable molecular weight. Resin thrombin can lose its fibrinogen-clotting power while esterase activity is retained. On the other hand the esterase activity can be depressed without diminishing the clotting activity. Resin thrombin lyses fibrin. When examined in an ultracentrifuge a single symmetrical peak was found with a sedimentation constant of S = 3.9 (20 °C., 0.1 M KCl, 5.5 mg./ml.) Citrate thrombin was also fractionated with the use of IRC-50 to obtain material with a specific activity of 47,000 units/mg. tyrosine.

scholarly journals THE EXTENT OF LOCAL DISPERSION OF INFECTIOUS AGENTS AS A FACTOR IN RESISTANCE TO INFECTION

1935 ◽  
Vol 61 (5) ◽  
pp. 617-642 ◽  
Author(s):  
F. Duran-Reynals
Keyword(s):  
Effective Concentration ◽  
The Other ◽  
Type I ◽  
Spreading Factor ◽  
Rabbit Skin ◽  
Local Dispersion ◽  
Other Hand ◽  
Infective Dose ◽  
Resistance To Infection ◽  
Minimal Effective Concentration

Progressively decreasing quantities of bacteria of some 20 strains were utilized in experiments upon the effect of dispersing the organisms in the rabbit skin through the agency of an extract of testicle or an invasive staphylococcus. The same was done with 6 strains of filterable viruses. The bacterial lesions were enhanced by spreading when the organisms introduced were above a certain number or quantity (minimal effective concentration) and on the other hand were partially or totally suppressed when their number was less than this. Virulence and minimal effective concentration were observed to be in inverse relationship. The lesions due to the filterable viruses studied were, on the other hand, enhanced by the spreading factor even when the quantity of virus approached the minimal infective dose. This happened irrespective of whether the virus caused severe lesions or slight ones. The highly virulent Pneumococcus Type I, injected into normal rabbits together with the spreading factor, yielded enhanced lesions even at practically its minimal infective dose; but when the resistance of the animal was raised with specific antiserum the lesions were totally suppressed by the experimental dispersion of the bacteria. When such an experiment was repeated on a filterable virus, vaccinia, no suppression took place as a result of the dispersion of the infective agent. The significance of the differences in the bacterial and virus phenomena is discussed.

scholarly journals Von Willebrand factor: structure, properties and role in the process of hemostasis

2020 ◽  
pp. 3-13
Author(s):  
N Shurko ◽  
Keyword(s):  
Molecular Weight ◽  
Von Willebrand Factor ◽  
Functional Ability ◽  
Platelet Adhesion ◽  
The Other ◽  
Hemostasis System ◽  
Other Hand ◽  
Thrombotic Complications ◽  
Von Willebrand ◽  
Willebrand Factor

The article reviews the scientific papars on the structure, function and biological role of von Willebrand factor (vWF). The vWF mainly was considered as the main factor in the development of bleeding disorders (von Willebrand’s disease). On the other hand, it can be able the cause thrombotic complications through to the functional ability of the factor to stimulate platelet adhesion. The aim of this work was to conduct an analysis of the structure of the factor, its role in the process of hemostasis to determine a border between two opposing processes. Von Willebrand factor is a hemostatic, multimeric glycoprotein, one of the key components of the hemostasis system, taking an active part at startup mechanisms of platelet adhesion at the site of vesselendothelial damage. On the other hand, another important function of vWF is co-factor activity related to coagulation factor VIII (FVIII), which is to stabilize its activity, promoting thrombin activation and preventing the cleavage of the molecule by blood plasma proteinases. The human gene of vWF is localized on the short arm of the 12 chromosome, contains 52 exons and covers approximately 180 kb. VWF is made by endothelial cells and by bone marrow megakaryocytes. The factor is preserved in the Weibel-Palade bodies of endotolial cells and α-granules of platelets. The primary pro-polypeptide consists of 2813 amino acid, of which 2050 form the mature peptide. The molecular weight of vWF is 220 kDa. In bloodstreamv WF circulates as a multimeric protein with a molecular weight from 400 to 20,000 kDa. The synthesized molecule has the next domain structure: D1-D2-D’-D3-A1-A2-A3-D4-C1-C2-C3-C4-C5-C6-CK. Domains are responsible for binding various proteins, including FVIII, fibrin, collagen, heparin, complement components etcetra. Von Willebrand disease (vWD) is the most common autosomal inherited disorder of the hemostasis system (from 0.6 to 2.0% of the population) and the cause is a genetic deficiency of quantitative and/or qualitative abnormal multimeric structure of the vWF molecule. There are three main subtypes of vWD. Quite often in such patients there is a decrease in FVIII activity, as an indirect consequence of changes in vWF. The basic principle of vWD treatment is based on the normalization of vWF and/or FVIII levels by increasing the level of external vWF under the action of desmopressin or the introduction of factor concentrates. In contrast to hereditary vWD, acquired von Willebrand syndrome is a relatively rare acquired bleeding of the blood coagulation system (incidence from 0.04 to 0.13 %) associated with various underlying diseases. For today a significant amount of research devoted to the relationship between vWF and thrombotic complications, that is due functional ability of the factor stimulate platelet adhesion. In particular, there are reports of the following complications in: pneumonia caused by Streptococcus pneumoniae; COVID-19; polycythemia vera; chronic kidney disease etcetra.

THE STRUCTURE OF PLATELET-REACTIVE SITES IN COLLAGENS

1987 ◽  
Author(s):  
M J Barnes ◽  
C M Fitzsimmons ◽  
L F Morton
Keyword(s):  
Platelet Aggregation ◽  
Type I Collagen ◽  
Quaternary Structure ◽  
The Other ◽  
Type I ◽  
Amino Acid Residues ◽  
Reactive Site ◽  
Parent Molecule ◽  
Type Iii ◽  
Helical Configuration

Collagen-induced platelet aggregation is an essential step in haemostasis and may be important in thrombosis, particularly that associated with the atherosclerotic plaque. We have located platelet-binding sites in collagen by fragmentation of the molecule with cyanogen bromide (CB) and measurement of the platelet aggregatory activity of the fragments following their renaturation to restore triple-helical configuration and polymerisation to introduce quaternary structure. We have found a high1y-reactive site in collagen type III located in the peptide α1(III)CB4 which was active at a concentration of less than 0.5μg/ml. The equivalent peptide from type I collagen α1(I)CB3 occurring in precisely the same location in the respective parent molecule (residues 403-551) and exhibiting a structure highly homologous to that of α1(III)CB4 was active only at concentrations higher than 200μg/ml. α1(I)CB7, the most active of the type I peptides, was able to cause platelet aggregation at around 5μg/ml whilst the equivalent type III peptide μ1(III)CB5 was inactive. Modification of specific amino acid residues indicated the importance of lysine in the activity of μ1(III)CB4 and of arginine in that of α1(I)CB7. Comparison of the structure of these peptides leads us to conclude that a reactive site comprises two basic residues, a specific distance apart, the conformation of one to the other dictated by collagen triple-helical configuration. One residue occurs in the sequence GlyPro(orHyp)LYS(orARG)GlyGlu, the other in GlyLYS(orARG)Pro(orHyp)GlyGlu. The lower reactivity of α1(I)CB7 relative to α1(III)CB4 can be attributed to the presence of two arginyl rather than lysyl residues and because the spacing of the two in CB4(G1y-LYS-Y-G1y-X-Y-G1y-X-LYS) represents a more favourable one than in CB7(Gly-X-ARG-Gly-X-Y-Gly-X-Y-Gly-ARG-Y).

scholarly journals A GIS Approach to Analyzing the Spatial Pattern of Baseline Resilience Indicators for Community (BRIC)

Water ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 1401 ◽  
Author(s):  
Chien-Hao Sung ◽  
Shyue-Cherng Liaw
Keyword(s):  
Natural Hazards ◽  
Principal Component ◽  
Community Resilience ◽  
The Other ◽  
Urban Region ◽  
Specific Situation ◽  
Social Resilience ◽  
Mountain Areas ◽  
Other Hand ◽  
Resilience Indicators

We explore the baseline resilience to natural hazards through the Baseline Resilience Indicators for Community (BRIC) in northeastern Taiwan. Based on the specific situation of our study site, we slightly modified the BRIC. Due to the correlation between some of the subcomponents, we apply principal component analysis (PCA) to solve this issue. Therefore, we slightly changed the classification of subcomponents. We aggregated economic resilience, social resilience, and community capital resilience into socioeconomic community resilience. The result of geographically weighted regression (GWR) shows that even though we modified the indicator, the BRIC we built is still valid. Through spatial autocorrelation analysis, it reveals that the urban region in plain areas is the cluster of high resilience areas. On the other hand, almost all the entire mountain areas are the cluster of low resilience areas. The topography is the most important factor to cause this distribution. Plain areas have favorable characteristics to trigger development and create high socioeconomic community resilience. Mountain areas, on the other hand, do not have these advantages. The distribution of institutional and infrastructure subcomponents shows no particular pattern. That is to say, institutional and infrastructure subcomponents do not influence the distribution of BRIC. The difference in socioeconomic community resilience causes the uneven distribution of baseline resilience to natural hazards. Nevertheless, the distribution of institutional and infrastructure resources is also a crucial issue. In our case, although the distribution of institutional and infrastructure follows the “distributive justice” approach and distribution randomly, whether it is an appropriate approach is still under debate.

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