scholarly journals Purification of marginal plates from bovine renal peroxisomes: identification with L-alpha-hydroxyacid oxidase B.

1991 ◽  
Vol 113 (1) ◽  
pp. 113-121 ◽  
Author(s):  
K Zaar ◽  
A Völkl ◽  
H D Fahimi
Keyword(s):  
Lattice Structure ◽  
Single Layer ◽  
Urate Oxidase ◽  
Crystalline Lattice ◽  
Additional Information ◽  
Cell Tissue ◽  
Sds Page ◽  
The Matrix ◽  
Marginal Plates

The matrix of mammalian peroxisomes frequently contains crystalline inclusions. The most common inclusions are membrane associated plate-like "marginal plates" of hitherto unknown nature in renal peroxisomes and central polytubular "cores" composed of urate oxidase in hepatic peroxisomes. In bovine kidney, peroxisomes of proximal tubules exhibit peculiar angular shapes that are caused by multiple marginal plates (Zaar, K., and H.D. Fahimi. 1990. Cell Tissue Res. 260:409-414). Enriched or highly purified peroxisome preparations from this source were used to purify and characterize marginal plates. By SDS-PAGE, one major polypeptide of Mr 33,500 was observed that corresponded to the marginal plate protein. This polypeptide was identified by its enzymatic activity as well as by immunoblotting and preembedding immunocytochemistry as the isozyme B of L-alpha-hydroxyacid oxidase (EC 1.4.3.2). Morphologically, marginal plates were revealed to consist of rectangular straight-edged sheets, exhibiting a defined crystalline lattice structure. The sheets apparently are composed of a single layer of protomers which associate laterally to form a plate-like structure. As deduced from the negative staining results and the additional information of the thickness of marginal plates, each protomer seems to consist of eight subunits forming a cube-like array. The tendency of L-alpha-hydroxyacid oxidase B to self-associate in vitro (Philips, D.R., J.A. Duley, D.J. Fennell, and R.S. Holmes. 1976. Biochim. Biophys. Acta. 427:679-687) corresponds to the mode of association of cubical protomers to form the so-called marginal plates in renal peroxisomes.

Hollow-Fiber Cartridges: Model Systems for Virus Removal From Blood

2006 ◽  
Author(s):  
Jeevan G. Menon ◽  
R. Paul Duffin ◽  
Richard H. Tullis ◽  
Frank G. Jacobitz
Keyword(s):  
Hollow Fiber ◽  
Model Systems ◽  
Efficient Removal ◽  
Therapeutic Application ◽  
Enveloped Viruses ◽  
Virus Removal ◽  
Additional Information ◽  
Blood Filter ◽  
The Matrix

Aethlon Medical is developing an extracorporeal blood filter as a therapeutic device designed to remove viruses and toxins from the blood of patients. The Hemopurifier is a modified hollow-fiber plasmapheresis cartridge containing an affinity matrix in the extra capillary space. The matrix contains a high mannose specific lectin as the active capture agent. The flow configuration of the device is that of Starling flow. The filter is designed to clear viruses and toxins from blood, delaying illness so the patient’s immune system can fight off the virus. Results to date indicate the efficient removal of a variety of enveloped viruses including HIV, HCV and poxviruses with in vitro evidence indicating the ability to capture Dengue fever virus, measles, mumps, influenza, Ebola and Marburg. Possible additional targets include bioweapons such as smallpox and bacterial toxins. A schematic of the use of the filter in a therapeutic application is shown in figure 1. In order to optimize the design of such a filter, the fluid mechanics of the device is modeled analytically and investigated experimentally. Additional information can be found in Tullis et al. [1], Tullis et al. [2], and Duffin and Tullis [2].

The Structure and Development of Microbodies in the Fat Body and other Tissues of an Insect (Calpodes Ethlius)

1970 ◽  
Vol 28 ◽  
pp. 148-149
Author(s):  
M. Locke ◽  
J. T. McMahon
Keyword(s):  
Electron Microscopy ◽  
Liquid Crystals ◽  
Fat Body ◽  
Competitive Inhibitor ◽  
Dense Core ◽  
Urate Oxidase ◽  
Blood Proteins ◽  
Free Base ◽  
The Core ◽  
The Matrix

The fat body of insects has always been compared functionally to the liver of vertebrates. Both synthesize and store glycogen and lipid and are concerned with the formation of blood proteins. The comparison becomes even more apt with the discovery of microbodies and the localization of urate oxidase and catalase in insect fat body.The microbodies are oval to spherical bodies about 1μ across with a depression and dense core on one side. The core is made of coiled tubules together with dense material close to the depressed membrane. The tubules may appear loose or densely packed but always intertwined like liquid crystals, never straight as in solid crystals (Fig. 1). When fat body is reacted with diaminobenzidine free base and H2O2 at pH 9.0 to determine the distribution of catalase, electron microscopy shows the enzyme in the matrix of the microbodies (Fig. 2). The reaction is abolished by 3-amino-1, 2, 4-triazole, a competitive inhibitor of catalase. The fat body is the only tissue which consistantly reacts positively for urate oxidase. The reaction product is sharply localized in granules of about the same size and distribution as the microbodies. The reaction is inhibited by 2, 6, 8-trichloropurine, a competitive inhibitor of urate oxidase.

Radiolabeled r-Hirudin as a Measure of Thrombin Activity at, or within, the Rabbit Aorta Wall In Vitro and In Vivo

1994 ◽  
Vol 71 (04) ◽  
pp. 499-506 ◽  
Author(s):  
Mark W C Hatton ◽  
Bonnie Ross-Ouellet
Keyword(s):  
Rabbit Aorta ◽  
Balloon Injury ◽  
Recombinant Hirudin ◽  
Aorta Wall ◽  
Thrombin Activity ◽  
Before And After ◽  
The Matrix

SummaryThe behavior of 125I-labeled recombinant hirudin towards the uninjured and de-endothelialized rabbit aorta wall has been studied in vitro and in vivo to determine its usefulness as an indicator of thrombin activity associated with the aorta wall. Thrombin adsorbed to either sulfopropyl-Sephadex or heparin-Sepharose bound >95% of 125I-r-hirudin and the complex remained bound to the matrix. Binding of 125I-r-hirudin to the exposed aorta subendothelium (intima-media) in vitro was increased substantially if the tissue was pre-treated with thrombin; the quantity of l25I-r-hirudin bound to the de-endothelialized intima-media (i.e. balloon-injured in vitro) correlated positively with the quantity of bound 131I-thrombin (p <0.01). Aortas balloon-injured in vivo were measured for thrombin release from, and binding of 125I-r-hirudin to, the de-endothelialized intimal surface in vitro; 125I-r-hirudin binding correlated with the amount of active thrombin released (p <0.001). Uptake of 125I-r-hirudin by the aorta wall in vivo was proportional to the uptake of 131I-fibrinogen (as an indicator of thrombin activity) before and after balloon injury. After 30 min in the circulation, specific 125I-r-hirudin binding to the uninjured and de-endo- thelialized (at 1.5 h after injury) aorta wall was equivalent to 3.4 (± 2.5) and 25.6 (±18.1) fmol of thrombin/cm2 of intima-media, respectively. Possibly, only hirudin-accessible, glycosaminoglycan-bound thrombin is measured in this way.

The Anticoagulant Properties of a Modified Form of Protein S

1988 ◽  
Vol 60 (02) ◽  
pp. 298-304 ◽  
Author(s):  
C A Mitchell ◽  
S M Kelemen ◽  
H H Salem
Keyword(s):  
Monoclonal Antibody ◽  
Anticoagulant Activity ◽  
Activated Protein C ◽  
Factor Xa ◽  
Protein S ◽  
Human Neutrophil Elastase ◽  
Factor X ◽  
Sds Page

SummaryProtein S (PS) is a vitamin K-dependent anticoagulant that acts as a cofactor to activated protein C (APC). To date PS has not been shown to possess anticoagulant activity in the absence of APC.In this study, we have developed monoclonal antibody to protein S and used to purify the protein to homogeneity from plasma. Affinity purified protein S (PSM), although identical to the conventionally purified protein as judged by SDS-PAGE, had significant anticoagulant activity in the absence of APC when measured in a factor Xa recalcification time. Using SDS-PAGE we have demonstrated that prothrombin cleavage by factor X awas inhibited in the presence of PSM. Kinetic analysis of the reaction revealed that PSM competitively inhibited factor X amediated cleavage of prothrombin. PS preincubated with the monoclonal antibody, acquired similar anticoagulant properties. These results suggest that the interaction of the monoclonal antibody with PS results in an alteration in the protein exposing sites that mediate the observed anticoagulant effect. Support that the protein was altered was derived from the observation that PSM was eight fold more sensitive to cleavage by thrombin and human neutrophil elastase than conventionally purified protein S.These observations suggest that PS can be modified in vitro to a protein with APC-independent anticoagulant activity and raise the possibility that a similar alteration could occur in vivo through the binding protein S to a cellular or plasma protein.

In Vitro Stability of a Tissue-Type Plasminogen Activator Mutant, BM 06.022, in Human Plasma

1994 ◽  
Vol 72 (06) ◽  
pp. 906-911 ◽  
Author(s):  
D C Rijken ◽  
E Groeneveld ◽  
M M Barrett-Bergshoeff
Keyword(s):  
Plasminogen Activator ◽  
Half Life ◽  
Polyacrylamide Gel Electrophoresis ◽  
Tissue Type ◽  
Single Chain ◽  
Tissue Type Plasminogen Activator ◽  
Type Plasminogen Activator ◽  
Sds Page ◽  
Chain Form

SummaryBM 06.022 is a non-glycosylated mutant of human tissue-type plasminogen activator (t-PA) comprising only the kringle-2 and proteinase domains. The in vivo half-life of BM 06.022 antigen is 4- to 5-fold longer than that of t-PA antigen. The in vitro half-life of the activity of BM 06.022 at therapeutic concentrations in plasma is shorter than that of t-PA. In this study the inactivation of BM 06.022 in plasma was further investigated.Varying concentrations of BM 06.022 were incubated in plasma for 0-150 min. Activity assays on serial samples showed a dose-dependent decline of BM 06.022 activity with a half-life from 72 min at 0.3 μg/ml to 38 min at 10 μg/ml. SDS-polyacrylamide gel electrophoresis (SDS-PAGE) followed by fibrin autography showed the generation of several BM 06.022-complexes. These complexes could be completely precipitated with antibodies against Cl-inactivator, α2-antiplasmin and α1-antitrypsin.During the incubation of BM 06.022 in plasma, plasmin was generated dose-dependently as revealed by varying degrees of a2-anti-plasmin consumption and fibrinogen degradation. SDS-PAGE and immunoblotting showed that single-chain BM 06.022 was rapidly (i. e. within 45 min) converted into its two-chain form at concentrations of 5 μg/ml BM 06.022 and higher.In conclusion, BM 06.022 at therapeutic concentrations in plasma was inactivated by Cl-inactivator, a2-antiplasmin and a j-antitrypsin. The half-life of the activity decreased at increasing BM 06.022 concentrations, probably as a result of the generation of two-chain BM 06.022 which may be inactivated faster than the single-chain form.

Formulation and Evaluation of Galantamine Hydrobromide Floating Matrix Tablet

2018 ◽  
Vol 8 (2) ◽  
Author(s):  
Poreddy Srikanth Reddy ◽  
Penjuri Subhash Chandra Bose ◽  
Vuppula Sruthi ◽  
Damineni Saritha
Keyword(s):  
Sodium Alginate ◽  
Xanthan Gum ◽  
Lag Time ◽  
Matrix Tablets ◽  
In Vitro Dissolution ◽  
Matrix Tablet ◽  
Compression Technique ◽  
Weight Variation ◽  
The Matrix

The aim of the present work was to prepare floating tablets of galantamine HBr using sodium alginate and xanthan gum as matrix forming carriers. Galantamine HBr is used for the treatment of mild to moderate Alzheimer's disease and various other memory impairments, in particular those of vascular origin. The matrix tablet formulations were prepared by varying the concentrations of sodium alginate and xanthan gum. The tablets were prepared by direct compression technique using PVP K-30 as a binder and sodium bicarbonate for development of CO2. The prepared matrix tablets were evaluated for properties such as hardness, thickness, friability, weight variation, floating lag time, compatibility using DSC and FTIR. In vitro dissolution was carried out for 12 hrs in 0.1N HCl at 37±0.5 ºC using USP paddle type dissolution apparatus. It was noted that, all the prepared formulations had desired floating lag time and constantly floated on dissolution medium by maintaining the matrix integrity. The drug release from prepared tablets was found to vary with varying concentration of the polymers, sodium alginate and xanthan gum. From the study it was concluded that floating drug delivery system for galantamine HBr can be prepared by using sodium alginate and xanthan gum as a carrier.

Showing the vegetation cover of flood-plains and river valleys on the Vegetation Map of Kazakhstan and middle Asia

1995 ◽  
pp. 58-66
Author(s):  
N. M. Kalibernova
Keyword(s):  
Plant Communities ◽  
Vegetation Cover ◽  
Flood Plain ◽  
Vegetation Map ◽  
Flood Plains ◽  
Additional Information ◽  
Ground Waters ◽  
The Matrix ◽  
River Valleys ◽  
Former Ussr

The fragment of the legend of the map concerning the vegetation of flood- plains and river-valleys in the subzones of northern and southern deserts is presented in the article. The map is compiled in Department of Vegetspon Geography and Cartography of Komarov Botanical Institute by a large team of botanists-geographers of the former USSR. The nature environments determining the development of vegetation of river-valleys in arid climate are conditioned by the intrazonal factors (alluvial and flood processes) at the background of natural zonal factors. Contrasts of environments and corresponding plant communities manifest themselves first of all. Mineralization of ground waters, salinity of soils, including the alluvial ones, are of essential importance. The practice of vegetation mapping of unstable habitats, to which floodplain landscapes belong, has shown that units of phytocoenological classification is of little use for this purpose. The heterogeneity of vegetation, consisting of short-term unstable serial communities generates a need for typification of space combinations of such phytocoenoses. For this purpose it is convenient to use generalized ecological-dinamic series, including plant communities of all levels within the limits of definite segment of valley. These series are the mapping units on the map. The vegetation of the first terrace is also nessecary to include in a single series with flood-plain vegetation because it has supplementary influence of ground waters. The higher divisions of the legend are based on zonal characters: vegetation of valleys in northern, middle and southern deserts. 13 numbers are used to show the vegetation cover of flood-plains and valleys. Additional 7 numbers are used for the out-of-valley meadow vegetation. The content is enriched by using of the letters by the numbers showing the geographic variants of series and ciphers for combination of series and out-of-series communities. The text legend is supplemented by the matrix (table), showing the subordination of subtitles, zonal position and geographic distribution of divisions. The types of series in the matrix are listed with indication of the main dominant species that gives the additional information on the legend divisions. The author's conclusion is that valley vegetation reveals clearly the zonal features, correlating with zonal (desert) vegetation.

scholarly journals Relative rates of biosynthesis of collagen type I, type V and type VI in calf cornea

1991 ◽  
Vol 274 (2) ◽  
pp. 615-617 ◽  
Author(s):  
P Kern ◽  
M Menasche ◽  
L Robert
Keyword(s):  
Type I Collagen ◽  
Collagen Type ◽  
Corneal Stroma ◽  
Collagen Type I ◽  
Type I ◽  
Type Vi Collagen ◽  
Sds Page ◽  
Proline Incorporation ◽  
Type V

The biosynthesis of type I, type V and type VI collagens was studied by incubation of calf corneas in vitro with [3H]proline as a marker. Pepsin-solubilized collagen types were isolated by salt fractionation and quantified by SDS/PAGE. Expressed as proportions of the total hydroxyproline solubilized, corneal stroma comprised 75% type I, 8% type V and 17% type VI collagen. The rates of [3H]proline incorporation, linear up to 24 h for each collagen type, were highest for type VI collagen and lowest for type I collagen. From pulse-chase experiments, the calculated apparent half-lives for types I, V and VI collagens were 36 h, 10 h and 6 h respectively.

scholarly journals The mechanism of in vitro clot lysis induced by vascular plasminogen activator

Blood ◽  
1984 ◽  
Vol 63 (6) ◽  
pp. 1331-1337 ◽  
Author(s):  
C Tran-Thang ◽  
EK Kruithof ◽  
F Bachmann
Keyword(s):  
Plasminogen Activator ◽  
Whole Blood ◽  
Apparent Molecular Weight ◽  
Clot Lysis ◽  
Initial Concentration ◽  
Low Concentrations ◽  
Sds Page ◽  
Tissue Plasminogen ◽  
Low Rate

Abstract The contribution of vascular plasminogen activator (v-PA) to the lysis of whole blood and plasma clots was investigated. v-PA released into the circulation after infusion of deamino-D-arginine vasopressin (DDAVP) was shown to bind quantitatively to plasma clots. Its apparent molecular weight, determined by the SDS-PAGE fibrin-agarose underlay method, was approximately 68,000 daltons, and its activity was quenched by antibodies against human tissue plasminogen activator (t-PA). Clots prepared from post-DDAVP plasma or post-DDAVP whole blood, rich in v- PA, did not lyse when incubated in imidazole buffer or normal plasma, as determined by the release of 125I from radiolabeled clots. However, clots made of v-PA-poor plasma or whole blood, incubated in v-PA-rich plasma, underwent substantial lysis. The concentration of PA in clots incubated in v-PA-rich plasma progressively increased in relation to the initial concentration of v-PA in the surrounding plasma. The results suggest that, at low concentrations of circulating v-PA, a hemostatic plug will lyse at a very low rate. However, when the v-PA concentration in the clot environment is increased, v-PA will accumulate progressively onto fibrin and induce thrombolysis.

scholarly journals Formulation and evaluation of bi-layer floating tablets of ziprasidone HCl and trihexyphenidyl HCl

2011 ◽  
Vol 47 (3) ◽  
pp. 545-553 ◽  
Author(s):  
Sathis Kumar Dinakaran ◽  
Santhos Kumar ◽  
David Banji ◽  
Harani Avasarala ◽  
Venkateshwar Rao
Keyword(s):  
Sustained Release ◽  
In Vitro Release ◽  
Chemical Properties ◽  
Matrix Tablets ◽  
In Vitro Dissolution ◽  
Floating Tablets ◽  
Ir Studies ◽  
Weight Variation ◽  
The Matrix

The purpose of this research study was to establish ziprasidone HCl NR 40 mg and trihexyphenidyl HCl SR 4mg in the form of bi-layer sustained release floating tablets. The tablets were prepared using sodium HPMC K4M / HPMC K15M as bio-adhesive polymers and sodium bicarbonate acting as a floating layer. Tablets were evaluated based on different parameters such as thickness, hardness, friability, weight variation, in vitro dissolution studies, content of active ingredient and IR studies. The physico-chemical properties of the finished product complied with the specifications. In vitro release from the formulation was studied as per the USP XXIII dissolution procedure. The formulations gave a normal release effect followed by sustained release for 12 h which indicates bimodal release of ziprasidone HCl from the matrix tablets. The data obtained was fitted to Peppas models. Analysis of n values of the Korsmeyer equation indicated that the drug release involved non-diffusional mechanisms. By the present study, it can be concluded that bi-layer tablets of ziprasidone HCl and trihexyphenidyl HCl will be a useful strategy for extending the metabolism and improving the bioavailability of Ziprasidone HCl and Trihexyphenidyl HCl.

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