THE USE OF POLYSTYRENE–ALLERGEN CONJUGATES FOR THE REMOVAL OF ANTIBODIES FROM SERA OF ALLERGIC INDIVIDUALS

1960 ◽  
Vol 38 (11) ◽  
pp. 1249-1253 ◽  
Author(s):  
L. Gyenes ◽  
A. H. Sehon
Keyword(s):  
Hydrochloric Acid ◽  
Protein Concentration ◽  
Complete Removal ◽  
Experimental Conditions ◽  
Comparative Analyses ◽  
Before And After

Polystyrene–ragweed conjugates were shown to remove specifically antibodies from sera of individuals allergic to ragweed. This observation is considered evidence that firm combination occurs in vitro between allergic antibodies and the homologous allergens. Comparative analyses of allergic sera before and after exposure to immunosorbents indicated that complete removal of skin-sensitizing, blocking, and hemagglutinating antibodies did not result in a measurable decrease in protein concentration, thus demonstrating that these factors are present only in minute amounts.Attempts to eîute allergic antibodies from the homologous immunosorbents under various experimental conditions did not lead to their recovery in significant yields; these antibodies could be recovered in small amounts by dissociation with hydrochloric acid at pH 3.

THE USE OF POLYSTYRENE–ALLERGEN CONJUGATES FOR THE REMOVAL OF ANTIBODIES FROM SERA OF ALLERGIC INDIVIDUALS

1960 ◽  
Vol 38 (1) ◽  
pp. 1249-1253
Author(s):  
L. Gyenes ◽  
A. H. Sehon
Keyword(s):  
Hydrochloric Acid ◽  
Protein Concentration ◽  
Complete Removal ◽  
Experimental Conditions ◽  
Comparative Analyses ◽  
Before And After

Polystyrene–ragweed conjugates were shown to remove specifically antibodies from sera of individuals allergic to ragweed. This observation is considered evidence that firm combination occurs in vitro between allergic antibodies and the homologous allergens. Comparative analyses of allergic sera before and after exposure to immunosorbents indicated that complete removal of skin-sensitizing, blocking, and hemagglutinating antibodies did not result in a measurable decrease in protein concentration, thus demonstrating that these factors are present only in minute amounts.Attempts to eîute allergic antibodies from the homologous immunosorbents under various experimental conditions did not lead to their recovery in significant yields; these antibodies could be recovered in small amounts by dissociation with hydrochloric acid at pH 3.

UV Detection and Avoidance of Protein in Basella alba leaf Mucilage Polysaccharide by differential precipitation

2021 ◽  
pp. 3093-3096
Author(s):  
Arvind P ◽  
Priyadarshini S ◽  
Duraiswamy B ◽  
Dhanabal SP ◽  
Ramu G
Keyword(s):  
Hydrochloric Acid ◽  
Protein Concentration ◽  
Lower Percentage ◽  
Uv Spectrum ◽  
Experimental Conditions ◽  
Ph Adjustment ◽  
Basella Alba ◽  
Residual Protein ◽  
Before And After ◽  
Differential Precipitation

Objective: In the aim of refining mucilage polysaccharide extracted from the leaf of Basella alba, extraction and differential precipitation of the protein content was studied. This was attempted by pH adjustment by adding Trichloroacetic acid (TCA) and Hydrochloric acid (HCl). Materials and Methods: The presence of residual protein before and after deproteinization in the polysaccharide solution was detected by UV spectrum analysis. The % polysaccharide, % polysaccharide loss, protein concentration and the deproteinization efficiency were studied as comparative indices to evaluate the precipitation experimental conditions using pH adjustment. Results: The result showed that 10% w/v TCA precipitated over 80% of the protein when the pH of the aqueous polysaccharide solution was 3. Discussion: TCA was proved to be superior to hydrochloric acid as evidenced by the highest deproteinization efficiency (83.3%). The polysaccharides of all the extracted solutions obtained were identified with only slight variations in percentage. The Hcl method excelled over the TCA method in obtaining polysaccharides with little lower percentage of polysaccharide loss (13.94 %). Conclusion: The TCA method will offer a room for deproteinization of polysaccharides if optimization is studied.

Effects of hypoxia and ischemia on autoregulation in postnatal intestine

1991 ◽  
Vol 261 (1) ◽  
pp. G152-G157 ◽  
Author(s):  
P. T. Nowicki ◽  
C. E. Miller ◽  
R. C. Edwards
Keyword(s):  
Blood Flow ◽  
Pressure Reduction ◽  
Experimental Conditions ◽  
Hypoxic Conditions ◽  
Significant Relationships ◽  
Norepinephrine Infusion ◽  
Before And After ◽  
Age Appropriate ◽  
Arterial Po2

Pressure-flow autoregulation was quantified within in vitro intestine from 3- and 35-day-old swine before and after lowering arterial PO2 (hypoxia) or lowering baseline blood flow by means of norepinephrine infusion (ischemia). Autoregulation was elicited by reducing arterial pressure approximately 33% from an age-appropriate baseline pressure. In 3-day-old intestine, autoregulation was unaffected by hypoxia or ischemia: vascular resistance was unchanged after pressure reduction, while Gf averaged -0.33 +/- 0.15 vs. -0.26 +/- 0.05 under control vs. hypoxic conditions, and -0.48 +/- 0.15 vs. -0.46 +/- 0.11 under control vs. ischemic conditions, respectively. In 35-day-old intestine, autoregulation was enhanced by hypoxia and ischemia. Under both experimental conditions, vasodilation was noted in response to pressure reduction: Gf averaged -0.04 +/- 0.14 vs. 0.38 +/- 0.08 under control vs. hypoxic conditions, and -0.12 +/- 0.10 vs. 0.28 +/- 0.08 under control vs. ischemic conditions, respectively. Regression analysis revealed a significant inverse linear correlation between Gf and venous PO2 in older, but not younger, subjects. Significant relationships between Gf and blood flow were not demonstrated in either group under any experimental condition. We conclude that autoregulation is enhanced within in vitro intestine from 35-, but not 3-day-old, swine during hypoxia or ischemia, and that reduction of venous PO2 is the principal factor responsible for the effect noted in older subjects.

Remineralization Potential of a New Toothpaste Formulation: An In-Vitro Study

2004 ◽  
Vol 5 (1) ◽  
pp. 18-30 ◽  
Author(s):  
Carlos A. Muñoz ◽  
Anna Torrado ◽  
Manuel Valiente ◽  
Wu Zhang ◽  
Yiming Li
Keyword(s):  
Ion Exchange ◽  
In Vitro Study ◽  
Ion Exchange Resin ◽  
Ion Exchange Resins ◽  
Experimental Conditions ◽  
Human Enamel ◽  
Before And After ◽  
Ph Cycling ◽  
Exchange Resins

Abstract The aim of the present study was to determine the ability of a dentifrice containing a mixture of ion-exchange resins (named NMTD), which supplies calcium, fluoride, phosphate, and zinc ions, to promote remineralization and/or inhibit demineralization of dental human enamel in a pH cycling model in vitro. A fluoride toothpaste was used as the control. The enamel specimens were tested for microhardness before and after 10 days and 16 days of the demineralizing and remineralizing treatments. The results of this study showed both dentifrices were effective in limiting in vitro enamel demineralization although the effects were not significantly different from each other. Inclusion of calcium and phosphate ion-exchange resins in the dentifrice containing a fluoride ion-exchange resin maintained a similar net outcome of the conventional dentifrice in the demineralization/ remineralization process under the experimental conditions employed. Citation Torrado A, Valiente M, Zhang W, et. al. Remineralization Potential of a New Toothpaste Formulation: An In-Vitro Study. J Contemp Dent Pract 2004 February;(5)1:018-030.

STUDIES ON SUSTAINED CONTRACEPTIVE EFFECTS WITH SUBCUTANEOUS POLYDIMETHYLSILOXANE IMPLANTS

1973 ◽  
Vol 73 (2) ◽  
pp. 347-359 ◽  
Author(s):  
G. Benagiano ◽  
M. Ermini ◽  
L. Carenza ◽  
P. Donini
Keyword(s):  
Urinary Excretion ◽  
Young Women ◽  
Ovarian Function ◽  
Megestrol Acetate ◽  
Bleeding Pattern ◽  
Experimental Conditions ◽  
The Third ◽  
Before And After

ABSTRACT Ovarian function was assessed in 10 healthy young women, before and after the insertion of 3 or 4 polydimethylsiloxane capsules filled with 20 mg of megestrol acetate. Each capsule released in vitro, approximately 20 μg/24 h of the hormone. Daily determination of the urinary excretion of FSH, LH, fractionated oestrogens and pregnanediol were performed in all subjects during one control cycle, the first and the third cycle after the insertion of the capsules. Out of 10, 8 control cycles were ovulatory according to all the parameters investigated. This compares with 15 ovulatory cycles out of a total of 20, examined after the insertion of the capsules. During treatment no changes were observed in the FSH excretion pattern; the mid-cycle LH peak was present in all ovulatory cycles, although it was usually much less evident under the action of megestrol acetate. The excretion of oestradiol was significantly increased in all subjects (P < 0.05) during the first cycle following implantation. Oestrone and oestriol excretion was also generally higher in patients bearing PDS capsules; however, this difference was not statistically significant. Pregnanediol levels were not affected by the treatment in all cycles considered to be ovulatory on the basis of all the parameters. The menstrual bleeding pattern did not change in the majority of cases. One patient had, during treatment with 3 capsules, two profuse break-through bleedings whereas another one became amenorrhoic two months after the insertion of 4 implants. It is concluded that megestrol acetate sustained release preparations do not inhibit ovulation under the experimental conditions used.

Electron microscopic study of the membrane glycoproteins in the rat kidney after cisplatin treatment

1989 ◽  
Vol 47 ◽  
pp. 912-913
Author(s):  
S.K. Aggarwal
Keyword(s):  
Alkaline Phosphatase ◽  
Rat Kidney ◽  
Light And Electron Microscopy ◽  
Kidney Tissue ◽  
Membrane Glycoproteins ◽  
Electron Microscopic ◽  
Before And After ◽  
Interstrand Cross Links ◽  
Cross Links

The proposed primary mechanism of action of the anticancer drug cisplatin (Cis-DDP) is through its interaction with DNA, mostly through DNA intrastrand cross-links or DNA interstrand cross-links. DNA repair mechanisms can circumvent this arrest thus permitting replication and transcription to proceed. Various membrane transport enzymes have also been demonstrated to be effected by cisplatin. Glycoprotein alkaline phosphatase was looked at in the proximal tubule cells before and after cisplatin both in vivo and in vitro for its inactivation or its removal from the membrane using light and electron microscopy.Outbred male Swiss Webster (Crl: (WI) BR) rats weighing 150-250g were given ip injections of cisplatin (7mg/kg). Animals were killed on day 3 and day 5. Thick slices (20-50.um) of kidney tissue from treated and untreated animals were fixed in 1% buffered glutaraldehyde and 1% formaldehyde (0.05 M cacodylate buffer, pH 7.3) for 30 min at 4°C. Alkaline phosphatase activity and carbohydrates were demonstrated according to methods described earlier.

Structural integrity after cold storage of human epidermal model in hypothermosol: A correlative ultrastructural and fluorescent assay

1994 ◽  
Vol 52 ◽  
pp. 270-271
Author(s):  
Henry H. Eichelberger ◽  
John G. Baust ◽  
Robert G. Van Buskirk
Keyword(s):  
Cold Storage ◽  
Structural Integrity ◽  
Culture Media ◽  
Cell Structure ◽  
Natural State ◽  
Sodium Cacodylate ◽  
Ruthenium Tetroxide ◽  
Cacodylate Buffer ◽  
Before And After

For research in cell differentiation and in vitro toxicology it is essential to provide a natural state of cell structure as a benchmark for interpreting results. Hypothermosol (Cryomedical Sciences, Rockville, MD) has proven useful in insuring the viability of synthetic human epidermis during cold-storage and in maintaining the epidermis’ ability to continue to differentiate following warming.Human epidermal equivalent, EpiDerm (MatTek Corporation, Ashland, MA) consisting of fully differentiated stratified human epidermal cells were grown on a microporous membrane. EpiDerm samples were fixed before and after cold-storage (4°C) for 5 days in Hypothermosol or skin culture media (MatTek Corporation) and allowed to recover for 7 days at 37°C. EpiDerm samples were fixed 1 hour in 2.5% glutaraldehyde in sodium cacodylate buffer (pH 7.2). A secondary fixation with 0.2% ruthenium tetroxide (Polysciences, Inc., Warrington, PA) in sodium cacodylate was carried out for 3 hours at 4°C. Other samples were similarly fixed, but with 1% Osmium tetroxide in place of ruthenium tetroxide. Samples were dehydrated through a graded acetone series, infiltrated with Spurrs resin (Polysciences Inc.) and polymerized at 70°C.

Observations of Frozen-Hydrated Microtubules

1990 ◽  
Vol 48 (1) ◽  
pp. 504-505
Author(s):  
D. Chrétien ◽  
D. Job ◽  
R.H. Wade
Keyword(s):  
Fourier Transforms ◽  
Structural Complexity ◽  
Image Contrast ◽  
Phase Behaviour ◽  
Experimental Conditions ◽  
Thin Sections ◽  
Surface Lattice ◽  
Cilia And Flagella ◽  
Outstanding Question

Microtubules are filamentary structures found in the cytoplasm of eukaryotic cells, where, together with actin and intermediate filaments, they form the components of the cytoskeleton. They have many functions and show various levels of structural complexity as witnessed by the singlet, doublet and triplet structures involved in the architecture of centrioles, basal bodies, cilia and flagella. The accepted microtubule model consists of a 25 nm diameter hollow tube with a wall made up of 13 paraxial protofilaments (pf). Each pf is a string of aligned tubulin dimers. Some results have suggested that the pfs follow a superhelix. To understand how microtubules function in the cell an accurate model of the surface lattice is one of the requirements. For example the 9x2 architecture of the axoneme will depend on the organisation of its component microtubules. We should also note that microtubules with different numbers of pfs have been observed in thin sections of cellular and of in-vitro material. An outstanding question is how does the surface lattice adjust to these different pf numbers?We have been using cryo-electron microscopy of frozen-hydrated samples to study in-vitro assembled microtubules. The experimental conditions are described in detail in this reference. The results obtained in conjunction with thin sections of similar specimens and with axoneme outer doublet fragments have already allowed us to characterise the image contrast of 13, 14 and 15 pf microtubules on the basis of the measured image widths, of the the image contrast symmetry and of the amplitude and phase behaviour along the equator in the computed Fourier transforms. The contrast variations along individual microtubule images can be interpreted in terms of the geometry of the microtubule surface lattice. We can extend these results and make some reasonable predictions about the probable surface lattices in the case of other pf numbers, see Table 1. Figure 1 shows observed images with which these predictions can be compared.

Inhibitory effects of bioaccessible anthocyanins and procyanidins from apple, red grape, cinnamon on α-amylase, α-glucosidase and lipase

2020 ◽  
pp. 1-9
Author(s):  
Pınar Ercan ◽  
Sedef Nehir El
Keyword(s):  
Inhibitory Activity ◽  
Digestive Enzymes ◽  
Positive Control ◽  
Anthocyanin Content ◽  
Inhibitory Effects ◽  
Total Anthocyanin ◽  
Total Anthocyanin Content ◽  
Before And After ◽  
Red Grape

Abstract. The goals of this study were to determine and evaluate the bioaccessibility of total anthocyanin and procyanidin in apple (Amasya, Malus communis), red grape (Papazkarası, Vitis vinifera) and cinnamon (Cassia, Cinnamomum) using an in vitro static digestion system based on human gastrointestinal physiologically relevant conditions. Also, in vitro inhibitory effects of these foods on lipid (lipase) and carbohydrate digestive enzymes (α-amylase and α-glucosidase) were performed with before and after digested samples using acarbose and methylumbelliferyl oleate (4MUO) as the positive control. While the highest total anthocyanin content was found in red grape (164 ± 2.51 mg/100 g), the highest procyanidin content was found in cinnamon (6432 ± 177.31 mg/100 g) (p < 0.05). The anthocyanin bioaccessibilities were found as 10.2 ± 1%, 8.23 ± 0.64%, and 8.73 ± 0.70% in apple, red grape, and cinnamon, respectively. The procyanidin bioaccessibilities of apple, red grape, and cinnamon were found as 17.57 ± 0.71%, 14.08 ± 0.74% and 18.75 ± 1.49%, respectively. The analyzed apple, red grape and cinnamon showed the inhibitory activity against α-glucosidase (IC50 544 ± 21.94, 445 ± 15.67, 1592 ± 17.58 μg/mL, respectively), α-amylase (IC50 38.4 ± 7.26, 56.1 ± 3.60, 3.54 ± 0.86 μg/mL, respectively), and lipase (IC50 52.7 ± 2.05, 581 ± 54.14, 49.6 ± 2.72 μg/mL), respectively. According to our results apple, red grape and cinnamon have potential to inhibit of lipase, α-amylase and α-glucosidase digestive enzymes.

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.

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