Effects of Submicellar Bile Salt Concentrations on Biological Membrane Permeability to Low Molecular Weight Non-Ionic Solutes†

Biochemistry ◽  
1996 ◽  
Vol 35 (24) ◽  
pp. 7936-7945 ◽  
Author(s):  
Ariela Albalak ◽  
Mark L. Zeidel ◽  
Stephen D. Zucker ◽  
Audrey A. Jackson ◽  
Joanne M. Donovan
Keyword(s):  
Molecular Weight ◽  
Bile Salt ◽  
Membrane Permeability ◽  
Biological Membrane ◽  
Low Molecular Weight ◽  
Ionic Solutes

scholarly journals Effects of a polyelectrolyte additive on the selective dialysis membrane permeability for low-molecular-weight proteins

2006 ◽  
Vol 22 (2) ◽  
pp. 491-499 ◽  
Author(s):  
D. H. Krieter ◽  
A. Morgenroth ◽  
A. Barasinski ◽  
H.-D. Lemke ◽  
O. Schuster ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Membrane Permeability ◽  
Low Molecular Weight ◽  
Dialysis Membrane ◽  
Low Molecular Weight Proteins

scholarly journals Effects of Polyelectrolytes on the Diffusion of Low Molecular Weight Ionic Solutes

1988 ◽  
Vol 20 (4) ◽  
pp. 345-349 ◽  
Author(s):  
Mohamed Z El-Abd ◽  
Ahmed A Zatout ◽  
Gomaa H Sedahmed ◽  
Ahmed H Negm
Keyword(s):  
Molecular Weight ◽  
Low Molecular Weight ◽  
Ionic Solutes

scholarly journals Antioxidant-Based Therapies in Male Infertility: Do We Have Sufficient Evidence Supporting Their Effectiveness?

Antioxidants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 220 ◽  
Author(s):  
Angela Maria Amorini ◽  
Ilaria Listorti ◽  
Gabriele Bilotta ◽  
Romina Pallisco ◽  
Miriam Wissam Saab ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Male Infertility ◽  
Nitrosative Stress ◽  
Biological Membrane ◽  
Case Control ◽  
Sufficient Evidence ◽  
Low Molecular Weight ◽  
Case Control Studies ◽  
Vast Number ◽  
Number Of Patients

Under physiological conditions, reactive oxygen species (ROS) play pivotal roles in various processes of human spermatozoa. Indeed, semen requires the intervention of ROS to accomplish different stages of its maturation. However, ROS overproduction is a well-documented phenomenon occurring in the semen of infertile males, potentially causing permanent oxidative damages to a vast number of biological molecules (proteins, nucleic acids, polyunsaturated fatty acids of biological membrane lipids), negatively affecting the functionality and vitality of spermatozoa. ROS overproduction may concomitantly occur to the excess generation of reactive nitrogen species (RNS), leading to oxidative/nitrosative stress and frequently encountered in various human pathologies. Under different conditions of male infertility, very frequently accompanied by morpho-functional anomalies in the sperm analysis, several studies have provided evidence for clear biochemical signs of damages to biomolecules caused by oxidative/nitrosative stress. In the last decades, various studies aimed to verify whether antioxidant-based therapies may be beneficial to treat male infertility have been carried out. This review analyzed the results of the studies published during the last ten years on the administration of low-molecular-weight antioxidants to treat male infertility in order to establish whether there is a sufficient number of data to justify antioxidant administration to infertile males. An analysis of the literature showed that only 30 clinical studies tested the effects of the administration of low-molecular-weight antioxidants (administered as a single antioxidant or as a combination of different antioxidants with the addition of vitamins and/or micronutrients) to infertile males. Of these studies, only 33.3% included pregnancy and/or live birth rates as an outcome measure to determine the effects of the therapy. Of these studies, only 4 were case–control studies, and only 2 of them found improvement of the pregnancy rate in the group of antioxidant-treated patients. Additionally, of the 30 studies considered in this review, only 43.3% were case–control studies, 66.7% enrolled a number of patients higher than 40, and 40% carried out the administration of a single antioxidant. Therefore, it appears that further studies are needed to clearly define the usefulness of antioxidant-based therapies to treat male infertility.

A high-performance oil-free backing pump for electron microscopes

1978 ◽  
Vol 36 (1) ◽  
pp. 110-111
Author(s):  
G.K.W. Balkau ◽  
E. Bez ◽  
J.L. Farrant
Keyword(s):  
Molecular Weight ◽  
Electron Microscope ◽  
Hot Spots ◽  
High Performance ◽  
Carbonaceous Material ◽  
Contamination Rate ◽  
Low Molecular Weight ◽  
Principal Source ◽  
Rotary Pumps ◽  
Electron Microscopes

The earliest account of the contamination of electron microscope specimens by the deposition of carbonaceous material during electron irradiation was published in 1947 by Watson who was then working in Canada. It was soon established that this carbonaceous material is formed from organic vapours, and it is now recognized that the principal source is the oil-sealed rotary pumps which provide the backing vacuum. It has been shown that the organic vapours consist of low molecular weight fragments of oil molecules which have been degraded at hot spots produced by friction between the vanes and the surfaces on which they slide. As satisfactory oil-free pumps are unavailable, it is standard electron microscope practice to reduce the partial pressure of organic vapours in the microscope in the vicinity of the specimen by using liquid-nitrogen cooled anti-contamination devices. Traps of this type are sufficient to reduce the contamination rate to about 0.1 Å per min, which is tolerable for many investigations.

Low-molecular-weight heparin in the prevention and treatment of thromboembolic disorders

1998 ◽  
Vol 1 (5) ◽  
pp. 166-174 ◽  
Author(s):  
Evelyn R Hermes De Santis ◽  
Betsy S Laumeister ◽  
Vidhu Bansal ◽  
Vandana Kataria ◽  
Preeti Loomba ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Low Molecular Weight Heparin ◽  
Low Molecular Weight ◽  
Prevention And Treatment
Sign in / Sign up

Export Citation Format

Share Document