scholarly journals A simplified method for obtaining 0.5-microns sections of small tissue specimens embedded in PEG.

1995 ◽  
Vol 43 (6) ◽  
pp. 637-643 ◽  
Author(s):  
K A Holtham ◽  
N B Slepecky

We describe a new method for embedding small specimens in polyethylene glycol (PEG) 4000. This method preserves cell morphology and provides sensitive immunocytochemical labeling with excellent subcellular resolution. Small tissues are embedded in agarose so that they can be grouped together and oriented for sectioning before infiltration with PEG 4000, a water-soluble polymer. Fixation, embedding, sectioning, and staining can be performed in 1 day. Results from immunocytochemical studies localizing actin and tubulin on 0.5-micron sections of PEG-embedded specimens are compared with those obtained on semi-thin sections of araldite-embedded specimens and demonstrate the ease, speed, and increased sensitivity of this embedding method.

2021 ◽  
Vol 78 ◽  
pp. 1-13
Author(s):  
A. Romanov ◽  
K. Ly ◽  
B. Kirchoff

Polyethylene glycol (PEG) is a non-carcinogenic, water-soluble polymer of ethylene oxide that has found wide applicability in industry and medicine, and has been used to embed and section small animal and plant tissues. Here we investigate the use of PEG for the rapid embedding of larger plant tissues. Ovaries of Musa velutina, Heliconia psittacorum and eight other species were embedded with a mixture of PEG 1450 and PEG 4000. It was found that tissues up to 6.5 × 10 mm could easily be embedded and sectioned in PEG. Embedded tissues could be stored at room temperature for up to 5 days with no detrimental effects. Sections were easily cut at 8–15 μm on a rotary microtome. PEG embedding resulted in equal or better tissue differentiation, better retention of cell inclusions, and reduced shrinkage compared with paraffin embedding. The process was also faster, requiring only 3–6 h compared with the 2 days needed for paraffin embedding. PEG is a rapid-embedding medium suitable for use with even large plant tissues.


2016 ◽  
Vol 40 (5) ◽  
pp. 4513-4518 ◽  
Author(s):  
Guang Li ◽  
Farong Tao ◽  
Qian Liu ◽  
Liping Wang ◽  
Zhuang Wei ◽  
...  

A novel reversible colorimetric chemosensor based on polyethylene glycol has been developed to detect Cu2+ ions in pure aqueous solution.


Author(s):  
Sharmin Akhter ◽  
Md. Sajjad Hossen ◽  
Md. Salahuddin ◽  
Muazzem Ahmed Sunny ◽  
Farzana Akther Sathi ◽  
...  

Glimepiride (GMP) is poorly water soluble drug, so solubility is the main constraint for its oral bioavailability. Because, poor aqueous solubility and slow dissolution rate of the glimepiride lead to irreproducible clinical response or therapeutic failure in some cases due to sub therapeutic plasma drug levels. In this study, binary and ternary solid dispersion of glimepiride were prepared with polyethylene glycol 6000 (PEG 6000) and polyethylene glycol 4000 (PEG 4000) at different weight ratios using the solvent evaporation and melting method. It was found the drug was released 0.46% after 5 minutes and only 15.83% within 60 minutes from active glimepiride on the other hand the release pattern of glimepiride from the binary formulation containing PEG 4000 in 1:5 (Formulation coding: G5) showed the best result. It was found that the ternary different SD formulation containing(PEG4000:Glimepiride:Povidone) In ratio 1:1:0.25 (Formulation coding were : G13) showed the best result. The drug was changed to amorphous form after solid dispersion. Itwas also evident that solid dispersions improve solubility of drug particles thus enhancing dissolution characteristics of drugs they increase the oral bioavailability. Peer Review History: UJPR follows the most transparent and toughest ‘Advanced OPEN peer review’ system. The identity of the authors and, reviewers will be known to each other. This transparent process will help to eradicate any possible malicious/purposeful interference by any person (publishing staff, reviewer, editor, author, etc) during peer review. As a result of this unique system, all reviewers will get their due recognition and respect, once their names are published in the papers. We expect that, by publishing peer review reports with published papers, will be helpful to many authors for drafting their article according to the specifications. Auhors will remove any error of their article and they will improve their article(s) according to the previous reports displayed with published article(s). The main purpose of it is ‘to improve the quality of a candidate manuscript’. Our reviewers check the ‘strength and weakness of a manuscript honestly’. There will increase in the perfection, and transparency. Received file Average Peer review marks at initial stage: 4.5/10 Average Peer review marks at publication stage: 7.5/10 Reviewer(s) detail: Name: Dr. Mohammed Abdel-Wahab Sayed Abourehab  Affiliation: Umm Al-Qura University;  Makkah Al-Mukarramah, Saudi Arabia E-mail: [email protected]   Name: Dr. Evren Alğin Yapar Affiliation: Turkish Medicines and Medical Devices Agency, Turkiye E-mail: [email protected] Comments of reviewer(s):


Author(s):  
Reinhard Stidl ◽  
Michael Denne ◽  
Jimena Goldstine ◽  
Bill Kadish ◽  
Katherine I. Korakas ◽  
...  

Polyethylene glycol (PEG) is an inert, water soluble polymer, used for decades in pharmaceuticals. Although PEG is considered safe, concerns persist about the potential adverse effects of long-term exposure to PEG-containing therapies, specifically in children, following the introduction of PEGylated recombinant factor products used for the treatment of hemophilia. Given the absence of long-term surveillance data, and to evaluate the potential risk, we estimated PEG exposure in the pediatric population receiving US Food and Drug Administration-approved parenteral therapies with pediatric indications. We used a range of pediatric weights and doses based on prescribing information (PI) or treatment guidelines. PIs and reporting websites were searched for information about adverse events (AEs). For a child weighing 50 kg on the highest prophylactic dose of a FVIII product, the range of total PEG exposure was 40–21,840 mg/year; for FIX products, the range was 13–1342 mg/year; and for other products, the range was 383–26,743 mg/year, primarily as a derivative excipient. No AE patterns attributable to PEG were found for any of these products, including potential renal, neurological, or hepatic AEs. Our analyses suggest the pediatric population has had substantial exposure to PEG for several decades, with no evidence of adverse consequences.


2018 ◽  
Vol 11 (3) ◽  
pp. 75 ◽  
Author(s):  
Reinhard Stidl ◽  
Michael Denne ◽  
Jimena Goldstine ◽  
Bill Kadish ◽  
Katherine Korakas ◽  
...  

Polyethylene glycol (PEG) is an inert, water soluble polymer, used for decades in pharmaceuticals. Although PEG is considered safe, concerns persist about the potential adverse effects of long-term exposure to PEG-containing therapies, specifically in children, following the introduction of PEGylated recombinant factor products used for the treatment of hemophilia. Given the absence of long-term surveillance data, and to evaluate the potential risk, we estimated PEG exposure in the pediatric population receiving PEGylated therapies with pediatric indications administered intravenously or intramuscularly. We used a range of pediatric weights and doses based on prescribing information (PI) or treatment guidelines. PIs and reporting websites were searched for information about adverse events (AEs). For a child weighing 50 kg on the highest prophylactic dose of a FVIII product, the range of total PEG exposure was 40–21,840 mg/year; for factor IX (FIX) products, the range was 13–1342 mg/year; and for other products, the range was 383–26,743 mg/year, primarily as a derivative excipient. No AE patterns attributable to PEG were found for any of these products, including potential renal, neurological, or hepatic AEs. Our analyses suggest the pediatric population has had substantial exposure to PEG for several decades, with no evidence of adverse consequences.


2005 ◽  
Vol 475-479 ◽  
pp. 1317-1320
Author(s):  
Zhong Zhou Yi ◽  
Shi-en Wang ◽  
Yong Huang

Ceramic gelcasting has to be performed in nitrogen to avoid surface-exfoliation and crack of the green body. The rapid drying of gelled bodies can cause nonuniform shrinkage. Non-uniform drying in various regions due to the solvent gradient, induces structural and residual stresses which cause defects, such as cracking, warpage and the other malformations. These malformations can be minimized or eliminated via adding a proper amount of water-soluble polymer polyethylene glycol(PEG).This study concentrates attention on dispersion, rheological property and gelation behavior in the new system, The flexural strength and microstructure of ZrO2 green bodies were measured and observed.


Author(s):  
Marwah Mohammed Hareeja ◽  
Eman B.H.Al-Khedairy

Ebastine (EBS) is a poorly water-soluble antihistaminic drug; it belongs to the class II group according to the biopharmaceutical classification system (BCS). The aim of the present work was to enhance the solubility, dissolution rate and micromeritic properties of the drug, by formulating it as spherical crystal agglomerates by Quasi Emulsion Solvent Diffusion (QESD) method. Spherical crystal agglomerates (SCAs) were prepared in presence of three solvents dichloromethane (DCM), water and chloroform as a good solvent, poor solvent and bridging solvent respectively.  Agglomeration of EBS involved the use of some hydrophilic polymers like polyethylene glycol 4000 (PEG 4000), polyvinyl pyrrolidine K30 (PVP K30), D-?-tocopheryl polyethylene glycol 1000 succinate (TPGS) and ?. cyclodextrin. The pure drug (EBS) and its agglomerates with and without polymers were characterized for their drug content, percentage yield, solubility, in vitro drug release study and micromeritic property as well as by optical microscope, Scanning Electron Microscopy (SEM), FTIR spectroscopic studies, Differential Scanning Calorimetry (DSC) and X-ray Diffraction (XRD). The results of this work showed that there was a   marketed enhancement in the solubility with improvement in dissolution rate, physiochemical properties, decrease in crystallinity and alteration in the crystal habit of the drug especially in presence of polymers. The best results were obtained with formula prepared by the combination of PEG 4000 and ?. cyclodextrin in the agglomeration process of (EBS).


Author(s):  
J. D. McLean ◽  
S. J. Singer

The successful application of ferritin labeled antibodies (F-A) to ultrathin sections of biological material has been hampered by two main difficulties. Firstly the normally used procedures for the preparation of material for thin sectioning often result in a loss of antigenicity. Secondly the polymers employed for embedding may non-specifically absorb the F-A. Our earlier use of cross-linked polyampholytes as embedding media partially overcame these problems. However the water-soluble monomers used for this method still extract many lipids from the material.


2011 ◽  
Vol 8 (2) ◽  
pp. 33
Author(s):  
Norfaezah Mazalan ◽  
Mazatulikhma Mat Zain ◽  
Nor Saliyana Jumali ◽  
Norhanim Mohalid ◽  
Zurina Shaameri ◽  
...  

Recently, research and development in the field of drug delivery systems (DDS) facilitating site-specific therapy has reached significant progression. DDS based on polymer micelles, coated micro- and nanoparticles, and various prodrug systems including water-soluble polymer have been prepared and extensively studied as novel drugs designed for cancer chemotherapy and brain delivery. Since polymers are going to be used in human, this study has the interest of testing two types of polymer, polyimides (PI) and polyphenylenevinylene (PPV) on neuronal cells. The objective of this study was to determine the possible neurotoxicity and potential neuroprotective effects of PI and PPV towards SH-SY5Y neuronal cells challenged by hydrogen peroxide (H2O2) as an oxidant. Cells were pretreated with either PI or PPV for 1 hour followed by incubation for 24 hour with 100 µM of H2O2. MTS assay was used to assess cell viability. Results show that PI and PPV are not harmful within the concentration up to 10 µM and 100 µM, respectively. However, PI and PPV do not protect neuronal cells against toxicity induced by H2O2 or further up the cell death.


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