Glycogen-dependent demixing of frog egg cytoplasm at increased crowding

Crowding increases the tendency of macromolecules to aggregate and phase separate, and high crowding can induce glass-like states of cytoplasm. To explore the effect of crowding in a well-characterized model cytoplasm we developed methods to selectively concentrate components larger than 25 kDa from Xenopus egg extracts. When crowding was increased 1.4x, the egg cytoplasm demixed into two liquid phases of approximately equal volume. One of the phases was highly enriched in glycogen while the other had a higher protein concentration. Glycogen hydrolysis blocked or reversed demixing. Quantitative proteomics showed that the glycogen phase was enriched in proteins that bind glycogen, participate in carbohydrate metabolism, or are in complexes with especially high native molecular weight. The glycogen phase was depleted of ribosomes, ER and mitochondria. These results inform on the physical nature of a glycogen-rich cytoplasm and suggest a role of demixing in the localization of glycogen particles in tissue cells.

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THE ROLE OF ADSORPTION IN CONTROLLING THE RATE OF REACTION OF CHLORAMBUCIL WITH PROTEIN

Canadian Journal of Biochemistry and Physiology ◽

10.1139/o63-105 ◽

1963 ◽

Vol 41 (4) ◽

pp. 931-939 ◽

Cited By ~ 14

Author(s):

J. H. Linford

Keyword(s):

Molecular Weight ◽

Carboxylic Acid ◽

Bovine Serum Albumin ◽

Inverse Relationship ◽

Reaction Rate ◽

The Other ◽

Alkylation Reaction ◽

Rate Of Reaction

Two proteins, haemoglobin and bovine serum albumin, have been studied with respect to their rates of alkylation by chlorambucil in vitro at 37 °C and pH 8.4. The proteins are of nearly the same molecular weight and free carboxylic acid content, but the alkylation reaction is 30 times faster with haemoglobin. On the other hand, the adsorption of chlorambucil by albumin is 20 times greater than that exhibited by haemoglobin. This inverse relationship between extent of adsorption and reaction rate suggests that adsorption protects the chlorambucil from activation in the solvent.

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Projects of the Consortium for Materials Development in Space

MRS Proceedings ◽

10.1557/proc-87-121 ◽

1986 ◽

Vol 87 ◽

Author(s):

Charles A. Lundquist

Keyword(s):

Surface Properties ◽

Phase Segregation ◽

Solid Particles ◽

The Other ◽

Material Transport ◽

Materials Development ◽

Immiscible Polymers ◽

Liquid Phases ◽

Properties Of Materials

AbstractThe Consortium for Materials Development in Space amalgamates private industries, the federal government, and universities for a common goal, commercial developments in space. The Consortium embraces research and development projects that benefit from unique attributes of space and that also rely on innovative applications of physical chemistry, material transport and their interactions. Three projects employ vapor transport of material from a solid source at one end of a sealed container to a growing crystal at the other end. The fourth and fifth projects have desired surface properties of materials as their objectives. In one of these, surfaces are electrodeposited, often with inert solid particles codeposited in the surface layer. The other project investigating surface properties makes use of the atomic oxygen environment outside a spacecraft. A surface exposed toward the direction of orbital motion is impacted by a beam predominantly of 5 electron volt oxygen atoms. This can produce unusual chemical reactions and surface morphology. The sixth project uses demixing of immiscible polymers in low-g to better understand the role of phase segregation in the properties of polymer blends and to accomplish the purification of materials by partitioning between two liquid phases.

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THE ROLE OF ADSORPTION IN CONTROLLING THE RATE OF REACTION OF CHLORAMBUCIL WITH PROTEIN

Canadian Journal of Biochemistry and Physiology ◽

10.1139/y63-105 ◽

1963 ◽

Vol 41 (1) ◽

pp. 931-939

Author(s):

J. H. Linford

Keyword(s):

Molecular Weight ◽

Carboxylic Acid ◽

Bovine Serum Albumin ◽

Inverse Relationship ◽

Reaction Rate ◽

The Other ◽

Alkylation Reaction ◽

Rate Of Reaction

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The role of membrane receptors for C3b and C3d in phagocytosis.

Journal of Experimental Medicine ◽

10.1084/jem.145.2.357 ◽

1977 ◽

Vol 145 (2) ◽

pp. 357-371 ◽

Cited By ~ 295

Author(s):

A G Ehlenberger ◽

V Nussenzweig

Keyword(s):

Molecular Weight ◽

High Molecular Weight ◽

Polymorphonuclear Leukocytes ◽

Membrane Receptors ◽

The Other ◽

Necessary Condition ◽

Complement Receptors ◽

Human Monocytes ◽

Particle Ingestion

In this paper we re-examine the roles of particle-bound IgG and C3 in phagocytosis of sheep erythrocytes (E) by monolayers of purified human monocytes and polymorphonuclear leukocytes (PMN). We conclude that two fragments of the C3 molecule, that is, C3b and C3d, can function as opsonins if the phagocyte has the appropriate membrane receptors. Monocytes, that bind both C3b and C3d, respond to both as opsonins. PMN, which do not bind C3d, respond only to particles opsonized with C3b. C3 and IgG have separate roles in phagocytosis. IgG, through its Fc fragment, directly stimulates particle ingestion, but is relatively inefficient at inducing particle binding. On the other hand, C3 primarily mediates the binding of the particle via complement receptors. A marked synergy exists between C3 and IgG in inducing phagocytosis. Thus, opsonization of the particle with C3 can be a necessary condition for particle ingestion, although by itself C3 does not trigger phagocytosis. The opsonic effect of C3 can be mimicked by a variety of nonimmunologic agents which enhance binding of the particle to the phagocyte without directly stimulating ingestion. The contact-inducing agents used include centrifugation of particle and phagocyte, high molecular weight dextran, protamine, and treatment of E with neuraminidase. These results suggest that the role of C3 in opsonization is mainly or exclusively one of establishing contact between particle and phagocyte.

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ANTI-INFLAMMATORY AND STRUCTURE PROTECTIVE EFFECTS OF HYALURONANS: ARE THESE EFFECTS MOLECULAR WEIGHT DEPENDENT?

Biomedical Engineering Applications Basis and Communications ◽

10.4015/s1016237211002323 ◽

2011 ◽

Vol 23 (01) ◽

pp. 13-20 ◽

Cited By ~ 3

Author(s):

Teng-Le Huang ◽

Horng-Chaung Hsu ◽

Chun-Hsu Yao ◽

Yueh-Sheng Chen ◽

Jeff Wang

Keyword(s):

Rheumatoid Arthritis ◽

Molecular Weight ◽

Reference Lists ◽

The Other ◽

Clinical Effects ◽

Protective Effects ◽

Anti Inflammatory ◽

Anti Inflammation ◽

Inflammatory Effect

Although hyaluronans (HA) has been proved to be effective in the treatment of patients with osteoarthritis and rheumatoid arthritis, the correlations between these effects and the molecular weight (MW) of HA have not been systematically followed. Many different HA preparations are now applied worldwide in clinical usage. Their MWs are very wide ranged (500–6,000 kDa). No systematic review especially addresses the role of HA's MW in the effects of anti-inflammation and structure protection. This study evaluates the literature of the basic and clinical studies on biological, pathological, and clinical effects of different MW HA. Databases were searched through PubMed (period 1978–2009), using the terms hyaluronan, hyaluronic acid, arthritis, and MW. Reference lists of relevant articles were controlled for additional references. We define the "high" MW (HMW) as MW greater than 2,000 kDa and define the "low" MW (LMW) as MW less than 2,000 kDa in the current study. Most data that support the structure protective effect of HA are from the studies with LMW HA. On the other hand, the majority of data that recommend the anti-inflammatory effect of HA are from the reports of HMW HA. In conclusion, we suggest that the effects of LMW HA were more structure protective and those of HMW HA were more anti-inflammatory.

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Plasma Levels of Protein S, Protein C, and Factor X: Effects of Sex, Hormonal State and Age

Thrombosis and Haemostasis ◽

10.1055/s-0038-1649925 ◽

1995 ◽

Vol 74 (05) ◽

pp. 1271-1275 ◽

Cited By ~ 36

Author(s):

C M A Henkens ◽

V J J Bom ◽

W van der Schaaf ◽

P M Pelsma ◽

C Th Smit Sibinga ◽

...

Keyword(s):

Regression Analysis ◽

Postmenopausal Women ◽

Protein C ◽

Blood Donors ◽

Premenopausal Women ◽

Protein S ◽

The Other ◽

Factor X ◽

Normal Ranges

SummaryWe measured total and free protein S (PS), protein C (PC) and factor X (FX) in 393 healthy blood donors to assess differences in relation to sex, hormonal state and age. All measured proteins were lower in women as compared to men, as were levels in premenopausal women as compared to postmenopausal women. Multiple regression analysis showed that both age and subgroup (men, pre- and postmenopausal women) were of significance for the levels of total and free PS and PC, the subgroup effect being caused by the differences between the premenopausal women and the other groups. This indicates a role of sex-hormones, most likely estrogens, in the regulation of levels of pro- and anticoagulant factors under physiologic conditions. These differences should be taken into account in daily clinical practice and may necessitate different normal ranges for men, pre- and postmenopausal women.

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The Kidney and Fibrinolysis

Thrombosis and Haemostasis ◽

10.1055/s-0038-1654207 ◽

1970 ◽

Vol 24 (01/02) ◽

pp. 026-032 ◽

Cited By ~ 2

Author(s):

N. A Marsh

Keyword(s):

Molecular Weight ◽

Plasminogen Activator ◽

Enzyme System ◽

Normal Animal ◽

Fibrinolytic Enzyme ◽

The Other ◽

Exclusion Chromatography ◽

Normal Urine ◽

Renal Origin ◽

Molecular Exclusion Chromatography

SummaryMolecular exclusion chromatography was performed on samples of urine from normal and aminonucleoside nephrotic rats. Normal urine contained 2 peaks of urokinase activity, one having a molecular weight of 22,000 and the other around 200,000. Nephrotic urine contained three peaks of activity with MW’s 126,000, 60,000 and 30,000. Plasma activator determined from euglobulin precipitate had a MW. in excess of 200,000. The results indicate that in the normal animal, plasma plasminogen activator does not escape into the urine in substantial quantities but under the conditions of extreme proteinuria there may be some loss through the kidney. The alteration in urokinase output in nephrotic animals indicates a greatly disordered renal fibrinolytic enzyme system.The findings of this study largely support the hypothesis that plasma plasminogen activator of renal origin and urinary plasminogen activator (urokinase) are different molecular species.

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Rapid Isolation of High Molecular Weight Urokinase from Native Human Urine

Thrombosis and Haemostasis ◽

10.1055/s-0038-1657167 ◽

1982 ◽

Vol 47 (03) ◽

pp. 197-202 ◽

Cited By ~ 23

Author(s):

Kurt Huber ◽

Johannes Kirchheimer ◽

Bernd R Binder

Keyword(s):

Molecular Weight ◽

High Molecular Weight ◽

Human Urine ◽

Gel Filtration ◽

Chain Structure ◽

The Other ◽

Single Chain ◽

Apparent Homogeneity ◽

Sequential Adsorption

SummaryUrokinase (UK) could be purified to apparent homogeneity starting from crude urine by sequential adsorption and elution of the enzyme to gelatine-Sepharose and agmatine-Sepharose followed by gel filtration on Sephadex G-150. The purified product exhibited characteristics of the high molecular weight urokinase (HMW-UK) but did contain two distinct entities, one of which exhibited a two chain structure as reported for the HMW-UK while the other one exhibited an apparent single chain structure. The purification described is rapid and simple and results in an enzyme with probably no major alterations. Yields are high enough to obtain purified enzymes for characterization of UK from individual donors.

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On the role of the dispute between "non-possessors" and "Josephites" in the culture of Moscow's prediction

Ukrainian Religious Studies ◽

10.32420/1998.7.141 ◽

1998 ◽

pp. 61-62

Author(s):

N. S. Jurtueva

Keyword(s):

The Other ◽

Moral Transformation ◽

15Th Century ◽

The Future ◽

Secular Power

In the XIV century. centripetal tendencies began to appear in the Moscow principality. Inside the Russian church, several areas were distinguished. Part of the clergy supported the specificobar form. The other understood the need for transformations in society. As a result, this led to a split in the Russian church in the 15th century for "non-possessors" and "Josephites". The former linked the fate of the future with the ideology of hesychasm and its moral transformation, while the latter sought support in alliance with a strong secular power.

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From Container to Claustrum: Projective Identification in Couples

Couple and Family Psychoanalysis ◽

10.33212/cfp.v4n2.2014.136 ◽

2014 ◽

Vol 4 (2) ◽

Cited By ~ 1

Author(s):

Tamara Feldman

Keyword(s):

Psychological Health ◽

Projective Identification ◽

The Self ◽

The Other ◽

Intimate Partners ◽

And Control ◽

The Relationship ◽

As If

This paper is a contribution to the growing literature on the role of projective identification in understanding couples' dynamics. Projective identification as a defence is well suited to couples, as intimate partners provide an ideal location to deposit unwanted parts of the self. This paper illustrates how projective identification functions differently depending on the psychological health of the couple. It elucidates how healthier couples use projective identification more as a form of communication, whereas disturbed couples are inclined to employ it to invade and control the other, as captured by Meltzer's concept of "intrusive identification". These different uses of projective identification affect couples' capacities to provide what Bion called "containment". In disturbed couples, partners serve as what Meltzer termed "claustrums" whereby projections are not contained, but imprisoned or entombed in the other. Applying the concept of claustrum helps illuminate common feelings these couples express, such as feeling suffocated, stifled, trapped, held hostage, or feeling as if the relationship is killing them. Finally, this paper presents treatment challenges in working with more disturbed couples.

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