scholarly journals Bile salt activation of cerebroside sulphate sulphohydrolase

1980 ◽  
Vol 189 (1) ◽  
pp. 45-49 ◽  
Author(s):  
A L Fluharty ◽  
R L Stevens ◽  
R T Miller ◽  
H Kihara
Keyword(s):  
Bile Salt ◽  
Metachromatic Leukodystrophy ◽  
Solid Phase ◽  
Type I ◽  
Type Ii ◽  
Salt Activation ◽  
Arylsulphatase A ◽  
High Concentrations ◽  
Activation Type ◽  
Putative Mutant

The cholate and taurodeoxycholate activations of cerebroside sulphate sulphohydrolase (cerebroside-3-sulphate 3-sulphohydrolase, EC 3.1.6.8) activity of arylsulphatase A (aryl-sulphate sulphohydrolase, EC 3.1.6.1) were compared. Taurodeoxycholate caused a sharp peak of response at a concentration of 1.25 mg/ml (type-I activation). Cholate also showed type-I activation but, in addition, it evoked a second, higher, response plateau at concentrations between 5 and 10 mg/ml (type-II activation). At the pH of the reaction, cholate is converted largely to the sparingly soluble free aicd, so at the high concentrations associated with type-II activation, copious precipitates were formed. It was found that the precipitated material was essential for the type-II activation. Type-I activation appears to involve bile salt interaction with substrate, while type-II activation appears to involve enzyme interaction with solid-phase cholic acid. the putative mutant arylsulphatase A in an unusual form of metachromatic leukodystrophy hydolysed cerebroside sulphate only in the presence of high levels of cholate. The type-II activation may thus be simulating a physiological desulphation reaction.

Evaluation of an enzyme immunoassay kit for estrogen receptor measurement--report II.

1988 ◽  
Vol 34 (10) ◽  
pp. 2053-2057 ◽  
Author(s):  
S Raam ◽  
D M Vrabel
Keyword(s):  
Enzyme Immunoassay ◽  
Binding Sites ◽  
Solid Phase ◽  
Functional Characterization ◽  
Quantitative Agreement ◽  
Type I ◽  
Type Ii ◽  
Immunoreactive Protein ◽  
Estrogen Binding

Abstract We present evidence to show that monoclonal antibodies to estrogen receptors (ER) in solid phase recognize the secondary estrogen binding sites with moderate to low affinity for estradiol (E2). An excellent quantitative agreement was found in five cytosols between the ER values obtained by the enzyme immunoassay (ER-EIA) and the amount of secondary estrogen binding sites measured by the assay involving dextran-coated charcoal (Clin Chem 1986;32:1496). The immunoreactive protein recognized by the antibody-coated beads, when allowed to react with ER(+) cytosols, is shown to bind [3H]estradiol only when the ligand concentration exceeds 8 nmol/L. Further biochemical and functional characterization of the immunoreactive protein is required to establish similarities/dissimilarities between this protein, high-affinity Type I ER sites, and the secondary sites such as Type II sites.

Enhanced Killing of Human B Lymphoma Targets by Combined Use of Cytokine Induced Killer (CIK) Cultures and Anti-CD20 Antibodies

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 4285-4285
Author(s):  
Alice Pievani ◽  
Camilla Belussi ◽  
Christian Klein ◽  
Alessandro Rambaldi ◽  
Josée Golay ◽  
...  
Keyword(s):  
Cytotoxic Activity ◽  
Nk Cell ◽  
Type I ◽  
Type Ii ◽  
B Lymphoma ◽  
Cik Cells ◽  
High Concentrations ◽  
Anti Cd20 ◽  
Cd20 Antibodies

Abstract Abstract 4285 Cytokine induced killer (CIK) cells are immune-effector cells that can be expanded in vitro in presence of rhIL-2, starting from peripheral blood mononuclear cells stimulated by interferon-γ and anti-CD3 antibody. CIK cultures at the end of in vitro expansion contain a mean of 40–75% CD3+CD56+ CIK cells, 20–60% CD3+CD56- T cells and 1–10% CD3-CD56+ NK cells. They show MHC-unrestricted cytotoxicity towards neoplastic but not normal targets. Their ease of production in vitro and anti-tumor potential have made them suitable candidates for cell therapy programs in solid and hematopoietic tumour treatment. CIK cells have shown cytotoxic activity in vitro against hematopoietic neoplastic cells, including B Non-Hodgkin's lymphoma (B-NHL). Other biological treatments available for B-NHL are the anti-CD20 antibodies such as type I Rituximab and a new generation glycoengineered type II GA101 antibody. These antibodies are thought to act mostly through immune mediated mechanisms including phagocytosis, complement mediated cytotoxicity (CDC) and antibody dependent cellular cytotoxicity (ADCC). GA101 has reduced CDC activity compared to type I anti-CD20 antibodies such as Rituximab. In addition, GA101 was defucosylated in its Fc portion to mediate increased ADCC. We have investigated the possibility of combining adoptive immunotherapy by Cytokine Induced Killer (CIK) cells with anti-CD20 type I Rituximab and type II GA101mAb, to optimize B-NHL therapy. CIK cultures alone demonstrated significant cytotoxic activity against a panel of B-NHL cell lines or freshly isolated samples, in either an autologous or allogeneic combination (26-27% killing at 30:1 ET ratio). This natural cytotoxic activity was mainly due to the predominating CD3+CD56+ CIK population (40-75%) present in the cultures. The addition of anti-CD20 mAbs increased CIK mediated cytotoxicity versus B lymphoma target cells and major enhancement was observed with GA101 compared to Rituximab (respectively 34% versus 16% increased lysis at 10:1 E:T ratio). This enhancement was mainly due to ADCC mediated by the small NK cell fraction (1-10%) present in CIK cultures because NK depletion by CD5 immunoselection at the end of expansion did not abolish the basal natural cytotoxicity of CIK cultures but abolished the enhancement observed in presence of anti-CD20 antibodies. The activation of NK cells in CIK cultures, evaluated by CD107a mobilization, was much more effective using GA101 rather than Rituximab (respectively 28% versus 19% CD107a+, p<0.005). Furthermore, in presence of human serum, Rituximab-mediated NK cell activation was inhibited to 70%, whereas the GA101-mediated was fully maintained. This inhibition was presumably due to complement C3 deposition, since it was not observed with either heat inactivated serum or high concentrations of human immunoglobulins. Inhibition was however observed with serum plus anti-C5 antibody eculizumab, which blocks the complement cascade downstream from C3. Lack of inhibition by serum of GA101-mediated NK cell degranulation was probably due to the higher affinity binding of this mAb to CD16 and not to a lower C3 activation, because at high concentrations, GA101 is nearly as efficient as Rituximab at activating complement and C3 deposition. Finally, addition of serum to CIK and mAbs did not modify overall the target cell killing by either antibody. More importantly, the use of a partially complement and CIK resistant lymphoma cell line such as WSU-NHL showed that resistance could be reverted by combined exposure to CIK cultures and monoclonal anti-CD20 antibodies. Indeed overall lysis of WSU-NHL, even in presence of serum, was significantly increasedby both anti-CD20 antibodies, and most effectively by GA101, compared to CIK cells alone. This was due to the combined action of CDC, ADCC and CIK mediated natural killing. In conclusion, CIK cultures could be used to treat B-NHL patients in both an autologous or allogeneic setting. Furthermore Rituximab but even more so GA101, could be used in vivo to enhance CIK therapeutic activity in B-NHL. These data may open the way to possible therapeutic exploitation of combined strategies of cell mediated and antibody mediated immunotherapy protocols which make use of different mechanisms of action to try and overcome resistance. Disclosures: Klein: Roche: Employment, Equity Ownership, Patents & Royalties. Rambaldi:Roche: Honoraria. Golay:Roche: Honoraria. Introna:Roche: Honoraria.

scholarly journals ORAL IMMUNIZATION AGAINST PNEUMOCOCCUS TYPES II AND III AND THE NORMAL VARIATION IN RESISTANCE TO THESE TYPES AMONG RATS

1931 ◽  
Vol 54 (6) ◽  
pp. 875-898 ◽  
Author(s):  
Victor Ross
Keyword(s):  
Bile Salt ◽  
Oral Immunization ◽  
Type I ◽  
Type Ii ◽  
Normal Variation ◽  
Type Iii ◽  
Active Immunity ◽  
The Dead ◽  
Partial Immunity

1. Considerable variation in the resistance of different rats toward Type II pneumococcus has been demonstrated. In general, older rats survive much greater doses than young ones, illustrating the acquisition of a natural partial immunity. The same is true for Type III but the immunity appears somewhat later in life and does not reach the same height. 2. An active immunity can be created against Types II and III in rats by feeding the dead organisms or the Berkefeld filtrate of the bile salt-dissolved cells. This immunity resembles that obtained against Type I in several respects.

Alterations of type II cell microvilli following ozone-induced alveolar injury

1988 ◽  
Vol 46 ◽  
pp. 326-327
Author(s):  
E. M. Haller ◽  
J. F. Paterson ◽  
J. M. Lundh ◽  
J. U. Balis
Keyword(s):  
Left Lobe ◽  
Ozone Exposure ◽  
Male Rats ◽  
Alveolar Type ◽  
Type I ◽  
Type Ii Cells ◽  
Type Ii ◽  
Type Ii Cell ◽  
High Concentrations ◽  
Injury And Repair

Ozone is a major oxidizing constituent in photochemical smog, and it is known to cause, at high concentrations, bronchiolo-al veoar injury with early loss of cilia and desquamation of alveolar type I cells, followed by proliferation of type II cells. In the present study, we investigated the sequential sur face alterations of alveolar type II cells using an established model for ozone-induced alveolar injury and repair.Fisher 344 male rats weighing 260±10g were exposed to 3 ppm ozone for 8 h. The animals were killed at various time intervals, inclduing zero time, 24, 48, and 96 h after termination of ozone exposure. The lungs were inflated at 20cm pressure with 2.5% glutaraldehyde in 0.1M Sorensen's phosphate buffer, ph 7.2, at 37 C for 4 h. Lung slices, 10 x 4 mm x 500 μm, were obtained by random selection from the left lobe, osmicated in 1% phosphate buffered OsO4, for 1 h at 4 C, dehydrated in a graded series of acetone, infiltrated with Freon 113, and critical-point dried using carbon dioxide.

Immunoelectron microscopic confirmation of the binding specificity of a rat anti-murine Type I pneumocyte monoclonal antibody

1990 ◽  
Vol 48 (3) ◽  
pp. 904-905
Author(s):  
Jon A. Hotchkiss ◽  
Stephen J. Kennel ◽  
Jack R. Harkema
Keyword(s):  
Volume Ratio ◽  
Microscopic Analysis ◽  
Binding Specificity ◽  
Alveolar Type ◽  
Type I ◽  
Type Ii ◽  
Type I Cells ◽  
Wide Range ◽  
High Concentrations ◽  
I Cells

Pulmonary alveolar are lined by an epithelium comprised of alveolar type I and type II pneumocytes. Alveolar type II cells synthesize and secrete pulmonary surfactant and are progenitor cells for type I cells. Although type I cells represent only 5% to 8% of the total cells in the lung, they cover more than 95% of the alveolar surface. Perhaps as a result of their large surface to volume ratio, type I cells may be damaged by a wide range of inhaled chemicals and gases, including high concentrations of oxygen often used in respiratory therapy.We produced a panel of rat monoclonal antibodies (MoAb) that bind specifically to cells and structural components in normal and fibrotic murine lungs. Light microscopic analysis of immunoperoxidase-stained lung sections from normal Balb/c mice suggested that one MoAb, 411-52, bound specifically to type I pneumocytes. MoAb 411-52 is a rat IgM antibody, as determined by its reactivity with class-specific anti-rat Ig antisera. The morphology of type I cells makes it difficult, if not impossible, to unequivocally identify a type I cell paraffin-embedded tissue sections. Therefore, we used immunoelectron microscopy to determine the cell binding specificity of this MoAb.

scholarly journals Progressive chromogenic anti-factor Xa assay and its use in the classification of antithrombin deficiencies

2014 ◽  
Vol 52 (12) ◽  
Author(s):  
Bettina Kovács ◽  
Zsuzsanna Bereczky ◽  
Anna Selmeczi ◽  
Réka Gindele ◽  
Zsolt Oláh ◽  
...  
Keyword(s):  
Factor Xa ◽  
Pleiotropic Effect ◽  
Reference Intervals ◽  
Type I ◽  
Type Ii ◽  
Factor X ◽  
Heparin Binding ◽  
Clotting Factors ◽  
At Deficiency ◽  
High Concentrations

AbstractAntithrombin (AT) is a slow-acting progressive inhibitor of activated clotting factors, particularly thrombin and activated factor X (FXa). However, the presence of heparin or heparan sulfate accelerates its effect by several magnitudes. AT deficiency, a severe thrombophilia, is classified as type I (quantitative) and type II (qualitative) deficiency. In the latter case mutations may influence the reactive site, the heparin binding-site (HBS) and exert pleiotropic effect. Heterozygous type II-HBS deficiency is a less severe thrombophilia than other heterozygous subtypes. However, as opposed to other subtypes, it also exists in homozygous form which represents a very high risk of venous thromboembolism.A modified anti-FXa chromogenic AT assay was developed which determines both the progressive (p) and the heparin cofactor (hc) activities, in parallel. The method was evaluated and reference intervals were established. The usefulness of the assay in detecting type II-HBS AT deficiency was tested on 78 AT deficient patients including 51 type II-HBS heterozygotes and 18 homozygotes.Both p-anti-FXa and hc-anti-FXa assays showed excellent reproducibility and were not influenced by high concentrations of triglyceride, bilirubin and hemoglobin. Reference intervals for p-anti-FXa and hc-anti-FXa AT activities were 84%–117% and 81%–117%, respectively. Type II-HBS deficient patients demonstrated low (heterozygotes) or very low (homozygotes) hc-anti-FXa activity with normal or slightly decreased p-anti-FXa activity. The p/hc ratio clearly distinguished wild type controls, type II-HBS heterozygotes and homozygotes.Concomitant determination of p-anti-FXa and hc-anti-FXa activities provides a reliable, clinically important diagnosis of type II-HBS AT deficiency and distinguishes between homozygotes and heterozygotes.

Molecular-dynamics studies on solid phase epitaxy of guest-free silicon clathrates

2001 ◽  
Vol 691 ◽  
Author(s):  
Shinji Munetoh ◽  
Koji Moriguchi ◽  
Teruaki Motooka ◽  
Kazuhito Kamei
Keyword(s):  
Activation Energy ◽  
Molecular Dynamics ◽  
Structural Transition ◽  
Solid Phase ◽  
Experimental Studies ◽  
Md Simulations ◽  
Type I ◽  
Solid Phase Epitaxy ◽  
Type Ii ◽  
Silicon Clathrates

ABSTRACTDynamical phenomena during the solid phase epitaxy (SPE) of guest-free Si clathrates (Si34 and Si46) via molecular-dynamics (MD) simulations using the Tersoff potential have been reported. The activation energy of SPE for Si34 has been found to correspond with the experimental value for the cubic diamond phase (c-Si; approximately 2.7eV), while the SPE rates of Si46 are much lower than that of c-Si. The structural transition from Si46 (type-I) to Si34 (type-II) can be also observed during the Si46 [001] SPE. The present results suggest that it is worthwhile to intensify experimental studies concerning crystal growth techniques of clathrate materials and these interesting Si forms may open up a new field in “silicon technologies”.

Central inspiration increases barosensitivity of neurons in rat rostral ventrolateral medulla

1995 ◽  
Vol 268 (4) ◽  
pp. R909-R918 ◽  
Author(s):  
T. Miyawaki ◽  
P. Pilowsky ◽  
Q. J. Sun ◽  
J. Minson ◽  
S. Suzuki ◽  
...  
Keyword(s):  
Activity Patterns ◽  
Rostral Ventrolateral Medulla ◽  
Ventrolateral Medulla ◽  
Type I ◽  
Respiratory Drive ◽  
Type Ii ◽  
Sprague Dawley ◽  
Type Iii ◽  
Type Iv ◽  
Activation Type

Barosensitive neurons in the rostral ventrolateral medulla (RVLM) often have a respiratory-related modulation of their activity. However, the extent of the interaction between baroreceptor and respiratory inputs is controversial. The main aim of the present study was to determine the effect of central respiratory drive (CRD) on the barosensitivity of RVLM neurons. Extracellular recordings were obtained from 68 barosensitive neurons in the RVLM of anesthetized, paralyzed, and bilaterally vagotomized Sprague-Dawley rats. Examination of phrenic-triggered histograms revealed five activity patterns among barosensitive neurons: inspiratory depression (type I, n = 20), early inspiratory activation (type II, n = 14), postinspiratory activation (type III, n = 18), expiratory depression (type IV, n = 5) and no modulation (type V, n = 11). In most neurons (types I and III and 56% of type II) inhibition produced by aortic nerve stimulation was greater in inspiration than in expiration. Cardiac-related modulation, as an index of natural phasic baroreceptor activation, was also greater in inspiration than expiration in type III neurons. The results demonstrate that CRD modulates the baroreflex at the level of the RVLM.

Imperfections in type I and type II diamonds

1962 ◽  
Vol 270 (1343) ◽  
pp. 538-552 ◽  
Keyword(s):  
Ultra Violet ◽  
Type I ◽  
Type Ii ◽  
Dislocation Loops ◽  
Screw Dislocations ◽  
X Ray ◽  
Transmission Electron ◽  
Infra Red ◽  
High Concentrations ◽  
Absorption Measurements

Natural diamonds have been thinned sufficiently by oxidation at 750 °C in oxygen or at 1350 °C in carbon dioxide for examination by transmission electron microscopy. Type I and type II diamonds as classified by infra-red and ultra-violet absorption measurements have been investigated and a difference in the nature of the imperfections in the two types has been found. Impurity platelets are present on {100} planes in type I diamonds and the relevant impurity has been identified as most probably nitrogen, since the density of platelets can be explained only by the high concentrations of nitrogen found in such diamonds by other workers. The presence of the nitrogen in platelet form can explain anomalous X-ray spikes reported around the normal Laue spots and also the fact that the nitrogen has been found to be present in a non-paramagnetic form. Small dislocation loops have been revealed on {111} planes near the nitrogen platelets and have been attributed to the condensation of vacancies following the formation of the platelets. Both these types of imperfection are absent in type II diamonds. Defects common to both types are dislocations and also long narrow dislocation dipoles which are considered to be formed by the movement of screw dislocations containing long jogs through the crystal at high temperatures. It is suggested that type II diamonds may have grown in nitrogen-free conditions at temperatures similar to those required for type I diamonds and have cooled slowly or they may have grown at lower temperatures than type I diamonds.

Heat-Etching with a Bullivant Type II Simple Freeze-Cleave Device

1970 ◽  
Vol 28 ◽  
pp. 106-107 ◽  
Author(s):  
Ronald S. Weinstein ◽  
N. Scott McNutt
Keyword(s):  
New Zealand ◽  
General Hospital ◽  
Massachusetts General Hospital ◽  
Type I ◽  
Type Ii ◽  
Collaborative Effort ◽  
Temperature And Pressure ◽  
The University

The Type I simple cold block device was described by Bullivant and Ames in 1966 and represented the product of the first successful effort to simplify the equipment required to do sophisticated freeze-cleave techniques. Bullivant, Weinstein and Someda described the Type II device which is a modification of the Type I device and was developed as a collaborative effort at the Massachusetts General Hospital and the University of Auckland, New Zealand. The modifications reduced specimen contamination and provided controlled specimen warming for heat-etching of fracture faces. We have now tested the Mass. General Hospital version of the Type II device (called the “Type II-MGH device”) on a wide variety of biological specimens and have established temperature and pressure curves for routine heat-etching with the device.

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