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At least 19 recordsLinked to original sources

An improved cellophane method for in vitro germination of recalcitrant pollen.

The cellophane technique of La Cour and Faberge has been improved by the use of a booklet of filter paper. The booklet consists of seven squares of filter paper stapled together; the cellophane on which the pollen is germinated is placed between the two top leaves of the booklet and the whole soaked in a sucrose-based nutrient medium for 15 min. This arrangement keeps the cellophane flat as it absorbs medium. The top leaf of the booklet is then removed, the pollen dusted on it and the completed preparation closed in a plastic-wrapped Petri dish. The lower leaves of the booklet keep the cellophane moist for up to 24 hr. Proportions of pollen grains germinating are at least as high as in the hanging drop method; pollen of species that germinate poorly or not all in hanging drops do well in this technique. Because the pollen tubes adhere tightly to the cellophane, staining, observation, and studies of various sorts are facilitated.

Agriculture

[Hygienic properties of cellophane film intended for food packaging].

The cellophane films intended for wrapping food products were studied. Investigations have established the presence of these films of the cellulose xanthogenate and products of its decomposition, of carbon bisulphide in particular. With their joint presence the determination of carbon bisulphide and hydrogen sulphide was done colourimetrically, the sensitivity of this method being 0.005 mg/l. Migration of carbon bisulphide from the cellophane into the atmosphere and water was investivaged. An interconnection between the amount of the migrated carbon bisulphide and the odour of aqueous cellophane extracts was disclosed. To improve sanitary and chemical properties of cellophane a more intensive washing off of sulphur-containing compounds from it is recommended.

Carbon Disulfide

Hemodialysis leukopenia. Pulmonary vascular leukostasis resulting from complement activation by dialyzer cellophane membranes.

Acute leukopenia occurs in all patients during the first hour of hemodialysis with cellophanemembrane equipment. This transient cytopenia specifically involves granulocytes and monocytes, cells which share plasma membrane reactivity towards activated complement components. The present studies document that complement is activated during exposure of plasma to dialyzer cellophane, and that upon reinfusion of this plasma into the venous circulation, granulocyte and monocyte entrapment in the pulmonary vasculature is induced. During early dialysis, conversion of both C3 and factor B can be demonstrated in plasma as it leaves the dialyzer. Moreover, simple incubation of human plasma with dialyzer cellophane causes conversion of C3 and factor B, accompanied by depletion of total hemolytic complement and C3 but sparing of hemolytic C1. Reinfusion of autologous, cellophane-incubated plasma into rabbits produces selective granulocytopenia and monocytopenia identical to that seen in dialyzed patients. Lungs from such animals reveal striking pulmonary vessel engorgement with granulocytes. The activated complement component(s) responsible for leukostasis has an approximate molecular weight of 7,000-20,000 daltons. Since it is generated in C2-deficient plasma and is associated with factor B conversion, it is suggested that activation of complement by dialysis is predominantly through the altermative pathway.

Adult

[Comparative evaluation of cuprophane and cellophane used as membranes for hemodialysis].

Investigations into the structure, mechanical properties and permeability of the Soviet-made cellophane, cellulose film No 100 and cuprophane have shown the Soviet-made cellophane membrane to be inferior to cuprophane with regard to the strength and permeability of low-molecular metabolites. High strength properties of the cellulose film No 100 go with a much more lower permeability than in the case of cuprophane and cellophane. Sterilization with gamma-irradiation does not have any material effect on the physico-mechanical and functional characteristics of the membranes. Ways and means for improving the strength and permeability of the hydrate-cellulose membranes are outlined.

Cellophane

[A simple method of preparing permanent squash preparations using cellophane].

A technique to prepare permanent squashed preparations of cell nuclei and chromosomes is proposed. Fix a piece of material on the slide with acetic alcohol (1:3), macerate with a 45% acetic acid, cover with hydrophilic cellophane previously soaked in a 45% acetic acid and then with a cover slip and filter paper to squash finally as it is routinely performed. After that soak off the cover slip with alcohol, post-fix the squashed preparation together with cellophane in alcohol for 5-10 min, unstick the cellophane, pass the preparation through alcohol once again and dry it. The subsequent treatment of the squashed preparation depends on the purpose of investigation. The slide may be tinctured overlaid with photoemulsion for autoradiography, or processed by different ways.

Animals

A simplified method of protein electroblotting after isoelectric focusing on an ultrathin polyacrylamide gel layer fixed on a cellophane support.

A method is described for isoelectric focusing of proteins, using an ultrathin-layer polyacrylamide gel on cellophane, followed by electrophoretic transfer of separated proteins onto a nitrocellulose membrane. The polyacrylamide gel is firmly attached to the cellophane and thus protected from mechanical damage; such gels are easily manipulated. Cellophane is permeable to ions and application of this gel support overcomes difficulties resulting from the removal of ultrathin gels from a plastic support on electroblotting. Proteins separated under nondenaturing conditions were transferred onto a nitrocellulose membrane and detected by the concanavalin A-peroxidase technique. The proposed approach makes it possible to analyze the variability of nondenatured proteins and glycoproteins of different origin.

Acrylic Resins

Cellophane--a dressing for split-thickness skin graft donor sites.

Cellophane paper has been used as a dressing for split-thickness skin graft donor sites in 251 patients between October 1985 and December 1989. Twelve donor sites in 10 patients were observed in detail to assess the usefulness of this material. The results of the study are presented and the merits and disadvantages of this dressing material have been discussed. In the opinion of the authors the cellophane paper dressing was found to be most satisfactory. It is also cheaper than the newly available dressing materials for the skin donor area.

Burns

The effect of cellophane wrapping of the pancreas in the Syrian golden hamster: autoradiographic observations.

We examined the effects of cellophane wrapping of the pancreas on the age-related uptake of tritiated thymidine (3H-TdR) by the differentiated cell types of the pancreas of the Syrian golden hamster. Fifty-two hamsters were studied. At 7 weeks of age, hamsters underwent cellophane wrapping (n = 32) or were allocated to a control group (n = 20). Animals 8-22 weeks of age (four at each interval) received 3H-TdR (2 microCi/g) intraperitoneally and were killed 1 h later. Pancreatic tissues from each animal was processed for autoradiography. The percent of acinar cells labeled with 3H-TdR at 8 weeks, in control and wrapped animals, was 1.17 +/- 0.26 and 1.51 +/- 0.38 respectively (p = N.S.). In control animals, this steadily diminished to 0.02 +/- 0.00 at 22 weeks. In wrapped animals, there was less of a tendency for acinar cell labeling to decrease with age, and the percent of labeled acinar cells in wrapped animals at 22 weeks was 0.05 +/- 0.00. The percent of ductular cells labeled with 3H-TdR at 8 weeks in control and wrapped animals was 0.24 +/- 0.24 and 0.98 +/- 0.24, respectively (p = N.S.), and at 22 weeks was 0.13 +/- 0.90 and 0.60 +/- 0.03, respectively (p less than 0.01). The percent of islet cells labeled with 3H-TdR at 8 weeks in control and wrapped animals was 0.16 +/- 0.01 and 0.42 +/- 0.01, respectively (p less than 0.05), and at 22 weeks was 0.18 +/- 0.01 and 0.63 +/- 0.05 (p less than 0.05), respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals

Foreign body reaction against cellophane in the athymic nude mice.

There are no differences in the multinucleate cell formation in normal and athymic mice after the subcutaneous implantation of a cellophane strip. The number of Ia+ epitheloid cells and multinucleate foreign body giant cells was lower and the number of epitheloid cells sharing the marker of activated macrophages (M 57) was higher in athymic compared to normal mice. The epitheloid cells of athymic and euthymic animals exhibited no difference in the expression of Mac-2 molecule. The difference of the expression of surface markers between athymic and euthymic animals does not influence the foreign body giant cell formation.

Animals

Permeability of cellophane membranes to parotid during dialysis.

Pooled paratoid saliva was dialyzed in cellophane membranes against water for periods of up to 1 week and loss of proteins was monitored by acrylamide gel-electrophoresis. A gradual loss of cationic proteins was observed whereas anionic proteins were not appreciably affected. Loss of the cationic proteins could be greatly reduced by performing dialyses against dilute electrolyte solutions rather than water. These effects were attributed primarily to electrostatic changes associated with the dialysis membranes.

Adult

Plasmid transformation of Bacillus cereus on cellophane membranes.

A simple approach to test the ability of bacteria to undergo natural genetic transformation is suggested. The basic feature of the approach is the cultivation of bacterial cells in the presence of exogenous (plasmid) DNA on cellophane membranes placed successively on nutrient and selective agar. Using this approach the ability of Bacillus cereus for "natural" genetic transformation was detected. Transformation frequencies varied from 10(-8) to 10(-6).

Bacillus cereus

In vitro transcription in E. coli crude lysates prepared on cellophane discs.

An in vitro RNA-synthesizing system consisting of gently lysed E. coli cells on cellophane discs is described. The system has been optimalized with respect to total RNA synthesis. Under certain standard conditions DNA dependent RNA polymerase (EC 2.7.7.6) is responsible for the majority of the RNA synthesis. The extensive rifampicin sensitivity of the synthesis indicates that most of the transcripts are initiated in vitro. The RNA synthesizing system described here has been developed with the aim of studying phage transcription in vitro. We show here that lysates of a P4 infected P2 lysogen support initiation and propagation of transcription from the P2 prophage.

Cellophane

A functional study of the skin barrier to evaporative water loss by means of repeated cellophane-tape stripping.

The functional role of different layers of the horny layer in preventing evaporative water loss was studied by an adhesive cellophane-tape stripping technique. The increase in transepidermal water loss, as described by a mathematical equation based on curve-fitting analysis, was shown to be proportional to the decrease in thickness of the horny layer. In the second half of the curve the experimental data showed slightly higher transepidermal-water-loss values than would be expected on the basis of proportionality with thickness of the stratum corneum. The data suggest that the outer layers of the horny layer are also important in forming a barrier to evaporative water loss.

Adhesives

Transepidermal potassium ion, chloride ion, and water flux across delipidized and cellophane tape-stripped skin.

The skin barrier was evaluated as a function of transepidermal water loss (TEWL) and electrolyte loss. Combination electrodes for chloride and pH determinations and a potassium ion electrode were utilized. Delipidization of the skin did not impair the electrolyte barrier, but did damage the epidermal water barrier. Cellophane tape stripping of normal stratum corneum resulted in an increase in outward transepidermal potassium and chloride ion flux, an increase in skin surface pH, and an increase in TEWL. It appears that damage to the epidermal water barrier does not necessarily result in damage to the epidermal electrolyte barrier. We found the potassium electrode facile to use and believe that a combination potassium electrode would be useful for investigating and assessing the epidermal electrolyte barrier.

Adolescent

[Comparative study on the effectiveness of modified Kato's cellophane thick smear and Stoll's dilution egg counting technique for quantitative fecal examination of helminth eggs].

A total of 197 fecal specimens was prepared for quantitative examination of helminth eggs by modified Kato's cellophane thick smear (M.C.T.S.) and Stoll's dilution egg counting technique (D.E.C.T.). The comparative effectiveness of two techniques was evaluated and conversion function was deduced. The average time required for the microscopic examination on one slide by M.C.T.S. was 12.6 minutes and that of D.E.C.T. was 14.6 minutes. M.C.T.S. showed lower false negative rate than D.E.C.T. in light worm burden cases. Functions to convert the counts obtained by M.C.T.S. to E.P.G. by Stoll's dilution egg counting technique were 47.86 x 10(0.87) logM.C.T.S. in A. lumbricoides, 41.69 x 10(0.82) logM.C.T.S. in T. trichiura and 63.10 x 10(0.85) logM.C.T.S. in C. sinensis. It was suggested M.C.T.S. be better than D.E.C.T. for the quantitative examination of intestinal helminthiases such as A. lumbricoides, T. trichiura, and C. sinensis infections even in the cases with low worm burden.

Cellophane

[Gastric sarcomas induced in rats by DMBA and cellophane].

An experimental model of gastric sarcoma was elaborated experimentally on 228 Wistar rats. Tumors were induced by single DMBA injections into the glandular stomach wall in rats or by securing a cellophane plate onto its anterior surface. Tumors developed in 95 rats. Most tumors would show a mesenchymatous origin (89.8% of cases) and may be defined as leiomyosarcomas partly polymorphocellular ones, and more rarely as fibro- and reticulosarcomas. Tumors of the adenocarcinoma and solid cancer type developed only after DMBA administration. It was noted that the tumors arisen develop metastases in the regional lymph nodes but not often.

9,10-Dimethyl-1,2-benzanthracene

Epidermal regeneration and percutaneous water loss following cellophane stripping of reptile epidermis.

The histological and physiological effects of the removal of superficial corneous epidermal materials have been studied in several squamate species and a caiman. The gross and microscopic anatomy of the squamate integument has characteristics which make cellophane stripping inherently variable, but in general, when corneous materials were removed, they are replaced over a period of one to two weeks, by a tissue with the histological characteristics of the normal alpha-layer. This tissue may be produced by stimulated germinal activity and/or metaplasia of the other presumptive cell populations. In caiman, the thickness of the corneous tissues of the outer scale surface is reduced by stripping and the tissue is restored to normal in approximately two weeks by stimulated germinal proliferation. Measurements of cutaneous water loss (CWL) before, immediately after, and during two weeks post-trauma revealed the following. There is a sudden rise in CWL immediately after stripping, and values decline over the next two weeks as the corneous tissues are replaced. The results are interpreted as indicating that, as in mammals, the impermeability of the epidermis depends on the thickness of the corneous materials. In squamates it appears that the physiological barrier is the alpha-layer of the epidermal generation, and while the beta-layer cannot be excluded as playing some role in reducing the permeability of the integument, its role appears to be primarily mechanical.

Animals

Effects of cellophane tape stripping of mouse skin on epidermal growth regulators (chalones).

Variations in epidermal chalones after a single surface application of methylcholanthrene and croton oil have been described in previous papers. This paper reports a study of the effect of adhesive tape stripping of the skin on epidermal growth regulators (G1 and G2 chalones). Pieces of adhesive tape were applied 6 times to the same area of skin in groups of mice. The short-term effects of tape stripping on epidermal DNA synthesis and on mitotic rate were studied at different intervals after stripping. Other groups of mice were killed at similar time intervals after stripping, and the treated area of skin was homogenized and extracted with water. The inhibitory effect of these extracts on normal epidermal DNA synthesis and mitotic rate was assayed in normal hairless mice. The resulting inhibitions were interpreted as an expression of the concentration of G1 or G2 chalone in the skin extracts. The first experiment confirmed that cellophane tape stripping gives rise to a short block in epidermal mitotic activity and probably also in DNA synthesis. This was followed by bimodal peaks of increased activity, the two maxima of labelling index being found on days 2 and 6, and the two maxima of mitotic rate on days 1-2 and 7. The concentrations of the two chalones in the skins of treated animals varied in inverse proportion to the alterations in the DNA synthesis and the mitotic rate, with one exception. Here there was initially a depression of the mitotic rate and a low concentration of G2 chalone. This was interpreted as a short reaction of the basel cells to the stripping trauma. It is concluded that adhesive tape stripping removes the differentiating cells and injures some basel cells, simultaneously altering the content of G1 and G2 chalones. The resulting increase in the rates of DNA synthesis and mitosis lasts only until the number of cells is high enough to produce growth-regulating substances (chalones) again. This theory may explain the changes observed. Since similar reactions are seen after both carcinogenic and co-carcinogenic chemical injury of the epidermis, the reaction pattern seems to be a general response to cell injury or cell removal.

Animals