scholarly journals Raman analysis of polyethylene glycols and polyethylene oxides

2018 ◽  
Vol 999 ◽  
pp. 012002 ◽  
Author(s):  
E A Sagitova ◽  
K A Prokhorov ◽  
G Yu Nikolaeva ◽  
A V Baimova ◽  
P P Pashinin ◽  
...  
Keyword(s):  
Polyethylene Glycols ◽  
Raman Analysis ◽  
Polyethylene Oxides

Fisiopatología de la hidrocefália idiopática de presión normal (parte 3): sistemaa glinfático

2016 ◽  
Vol 21 (2) ◽  
pp. 28-37
Author(s):  
Oscar Solís-Salgado ◽  
José Luis López-Payares ◽  
Mauricio Ayala-González
Keyword(s):  
Amyloid Beta ◽  
Interstitial Fluid ◽  
Amyloid Β ◽  
Bulk Flow ◽  
Polyethylene Glycols ◽  
Brain Interstitial Fluid ◽  
El Sistema ◽  
Arterial Pulsation ◽  
The Brain

Las vías de drenaje solutos del sistema nervioso central (SNC) participan en el recambio de liquido intersticial con el líquido cefalorraquídeo (LIT-LCR), generando un estado de homeostasis. Las alteraciones dentro de este sistema homeostático afectará la eliminación de solutos del espacio intersticial (EIT) como el péptido βa y proteína tau, los cuales son sustancias neurotóxicas para el SNC. Se han utilizado técnicas experimentales para poder analizar el intercambio LIT-LCR, las cuales revelan que este intercambio tiene una estructura bien organizada. La eliminación de solutos del SNC no tiene una estructura anatómica propiamente, se han descubierto vías de eliminación de solutos a través de marcadores florecentes en el espacio subaracnoideo, cisternas de la base y sistema ventricular que nos permiten observar una serie de vías ampliamente distribuidas en el cerebro. El LCR muestra que tiene una función linfática debido a su recambio con el LIT a lo largo de rutas paravasculares. Estos espacios que rodean la superficie arterial así como los espacios de Virchow-Robin y el pie astrocitico junto con la AQP-4, facilitan la entrada de LCR para-arterial y el aclaramiento de LIT para-venoso dentro del cerebro. El flujo y dirección que toma el LCR por estas estructuras, es conducido por la pulsación arterial. Esta función será la que finalmente llevara a la eliminación de estas sustancias neurotóxicas. En base a la dependencia de este flujo para la eliminación de sustancias se propone que el sistema sea llamado “ la Vía Glinfática”. La bibliografía así como las limitaciones que se encuentran en esta revisión están dadas por la metodología de búsqueda que ha sido realizada principalmente en PubMed utilizando los siguientes términos Mesh: Cerebral Arterial Pulsation, the brain via paravascular, drainage of amyloid-beta, bulk flow of brain interstitial fluid, radiolabeled polyethylene glycols and albumin, amyloid-β, the perivascular astroglial sheath, Brain Glymphatic Transport.

Europium and cerium extraction by the nitrobenzene solution of dicarbolide in the presence of polyethylene glycols

1986 ◽  
Vol 51 (3) ◽  
pp. 498-515 ◽  
Author(s):  
Emanuel Makrlík ◽  
Petr Vaňura
Keyword(s):  
Molecular Weight ◽  
Polyethylene Glycol ◽  
Organic Phase ◽  
Perchloric Acid ◽  
Equilibrium Constants ◽  
Polyethylene Glycols ◽  
Individual Species ◽  
Nitrobenzene Solution ◽  
Separation Factors ◽  
Equilibrium Data

Extraction of Eu3+ and Ce3+ microamounts from 0.1-0.4M perchloric acid by the nitrobenzene solution of dicarbolide H+[Co(C2B9H11)2]- in the presence of polyethylene glycols (Mr = 200, 300, 400) has been studied. The equilibrium data and the typical maxima on the dependence of the metal distribution ratio on the total analytical concentration of polyethylene glycol in the system can be explained assuming that the species ML3+org, ML3+2org, ML3+3org, MLH2+-1org, and HL+org (where M3+ = Eu3+, Ce3+; L = polyethylene glycol) are extracted into the organic phase. The values of extraction and equilibrium constants in the organic phase were determined and the effect of the polyethylene glycol molecular weight on the equilibrium constants and on the abundances of individual species in the organic phase is discussed. It has been found that the addition of polyethylene glycol to the acid - nitrobezene - dicarbolide system increases the values of the separation factors αCe/Eu.

Haemoglobin stabilization during lyophilization with saccharides. Perturbation effect of polyethylene glycols

1981 ◽  
Vol 46 (8) ◽  
pp. 1856-1859 ◽  
Author(s):  
Tomáš I. Přistoupil ◽  
Stanislav Ulrych ◽  
Marie Kramlová
Keyword(s):  
Polyethylene Glycols ◽  
Stabilizing Effect ◽  
Perturbation Effect ◽  
Effect Of Glucose ◽  
Mechanical Nature

The stabilizing effect of glucose and sucrose upon haemoglobin molecules against oxidation during lyophilization was perturbated by the presence of fluid or greasy polyethylene glycols (m.w. 300-600 daltons) but not of the rigid ones (m.w. 1 500-6 000 daltons). The results corroborate the idea of a simple mechanical nature of haemoglobin stabilization under study.

Extraction of polyethylene glycols with dicarbolide solutions in nitrobenzene

1990 ◽  
Vol 55 (8) ◽  
pp. 1959-1967 ◽  
Author(s):  
Petr Vaňura ◽  
Pavel Selucký
Keyword(s):  
Polyethylene Glycol ◽  
Molecular Mass ◽  
Extraction Constant ◽  
Metal Extraction ◽  
Polyethylene Glycols ◽  
Relative Molecular Mass ◽  
Published Data ◽  
Average Molecular Mass ◽  
Peg 400 ◽  
Extraction Constants

The extraction of polyethylene glycol of average molecular mass 400 (PEG 400) with dicarbolide solution in nitrobenzene and of longer-chain polyethylene glycol, of average molecular mass 1 500 (PEG 1 500), with chlorinated dicarbolide solution in nitrobenzene was studied. During the extraction of PEG 400, the polyethylene glycol solvates the Horg+ ion in the organic phase giving rise to the HLorg+ species (L is polyethylene glycol). The obtained value of the extraction constant Kex(HLorg+) = 933 is consistent with published data of metal extraction. Extraction of PEG 1 500 was treated applying the simplified assumption that the thermodynamic behaviour of PEG 1 500 is the same as that of n molecules of polyethylene glycol with relative molecular mass 1 500/n, each solvating one cation. For this model, the value of n = 3.2 ± 1.1 and the values of the extraction constants of the HL1/n,org+ and HL2/n,org+ species were obtained by using the adapted program LETAGROP. This value of n is consistent with published extraction data in the presence of polyethylene glycol with a relative molecular mass from 200 to 1 000.

Codeposition of copper and tin from acidic sulfate solutions containing polyethylene glycols. Effect of length of the hydrocarbon chain

2008 ◽  
Vol 14 (4) ◽  
pp. 507-514 ◽  
Author(s):  
Arvydas Survila ◽  
Dalia Bražinskienė ◽  
Stasė Kanapeckaitė ◽  
Zenius Mockus ◽  
Vitalija Jasulaitienė
Keyword(s):  
Hydrocarbon Chain ◽  
Polyethylene Glycols ◽  
Sulfate Solutions ◽  
Acidic Sulfate

Removal of polyethylene glycols from wastewater: A comparison of different approaches

Chemosphere ◽  
2021 ◽  
Vol 273 ◽  
pp. 129725
Author(s):  
Loris Pietrelli ◽  
Sergio Ferro ◽  
Andrea P. Reverberi ◽  
Marco Vocciante
Keyword(s):  
Polyethylene Glycols

scholarly journals 3D Clumps/Extracellular Matrix Complexes of Periodontal Ligament Stem Cells Ameliorate the Attenuating Effects of LPS on Proliferation and Osteogenic Potential

2021 ◽  
Vol 11 (6) ◽  
pp. 528
Author(s):  
Spoorthi Ravi Banavar ◽  
Swati Yeshwant Rawal ◽  
Shaju Jacob Pulikkotil ◽  
Umer Daood ◽  
Ian C. Paterson ◽  
...  
Keyword(s):  
Stem Cells ◽  
Periodontal Ligament ◽  
3D Culture ◽  
Osteogenic Potential ◽  
Culture Methods ◽  
Periodontal Ligament Stem Cells ◽  
Raman Analysis ◽  
Atp Production ◽  
Tnf Α ◽  
Inflammatory Milieu

Background: The effects of lipopolysaccharide (LPS) on cell proliferation and osteogenic potential (OP) of MSCs have been frequently studied. Objective: to compare the effects of LPS on periodontal-ligament-derived mesenchymal stem cells (PDLSCs) in monolayer and 3D culture. Methods: The PDLSCs were colorimetrically assessed for proliferation and osteogenic potential (OP) after LPS treatment. The 3D cells were manually prepared by scratching and allowing them to clump up. The clumps (C-MSCs) were treated with LPS and assessed for Adenosine triphosphate (ATP) and OP. Raman spectroscopy was used to analyze calcium salts, DNA, and proline/hydroxyproline. Multiplexed ELISA was performed to assess LPS induced local inflammation. Results: The proliferation of PDLSCs decreased with LPS. On Day 28, LPS-treated cells showed a reduction in their OP. C-MSCs with LPS did not show a decrease in ATP production. Principal bands identified in Raman analysis were the P–O bond at 960 cm−1 of the mineral component, 785 cm−1, and 855 cm−1 showing qualitative changes in OP, proliferation, and proline/hydroxyproline content, respectively. ELISA confirmed increased levels of IL-6 and IL-8 but with the absence of TNF-α and IL-1β secretion. Conclusions: These observations demonstrate that C-MSCs are more resistant to the effects of LPS than cells in monolayer cell culture. Though LPS stimulation of C-MSCs creates an early pro-inflammatory milieu by secreting IL-6 and IL-8, PDLSCs possess inactivated TNF promoter and an ineffective caspase-1 activating process.

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