Application of a novel human cervical mucin-based assay demonstrates the absence of increased mucinase activity in bacterial vaginosis

2002 ◽  
Vol 13 (11) ◽  
pp. 755-760 ◽  
Author(s):  
R Wiggins ◽  
M R Millar ◽  
P W Soothill ◽  
S J Hicks ◽  
A P Corfield
Keyword(s):  
Enzyme Activity ◽  
Bacterial Vaginosis ◽  
Gestational Age ◽  
Enzyme Activities ◽  
Significant Elevation ◽  
Term Birth ◽  
Large Numbers ◽  
Mucus Barrier ◽  
Individual Enzyme

Enzymes produced in bacterial vaginosis (BV) have been proposed as possible mediators of pre-term birth. Most studies have concentrated on mid-trimester measurements of enzyme activity, and utilize synthetic substrates to measure enzyme activity, which may not accurately represent mucinase activity in vivo. We have developed a novel ELISA mucinase assay using biotinylated human cervical mucin as a substrate. The assay is rapid, sensitive and can be used to screen large numbers of samples. The new assay has been used to assess vaginal mucinase activities in 92 women <14 weeks gestational age with and without BV. No differences in mucinase activity were detected between normal and BV groups while significant elevation of sialidase and other glycosidases was confirmed as reported before. This study shows that significant mucinase activity is a normal event in the mucus barrier, but does not reflect changes identified for individual enzyme activities associated with BV.

scholarly journals A strategy for increasing an in vivo flux by genetic manipulations. The tryptophan system of yeast

1992 ◽  
Vol 287 (2) ◽  
pp. 473-479 ◽  
Author(s):  
P Niederberger ◽  
R Prasad ◽  
G Miozzari ◽  
H Kacser
Keyword(s):  
Enzyme Activity ◽  
Metabolic Control ◽  
Enzyme Activities ◽  
Metabolic Control Analysis ◽  
Control Analysis ◽  
Additive Effects ◽  
Synthesis System ◽  
Genetic Manipulations ◽  
In Vivo Flux

Decreases in enzyme activity often have little effect on the flux carried by the pathway. Similarly, up-modulation of single genes, and hence of the dependent enzyme concentrations, is frequently found to be ineffective in increasing the flux in the pathway in which the enzyme occurs. This insensitivity to enzyme variation is demonstrated experimentally for five separate enzymes in the tryptophan synthesis system of yeast, first by down-modulation of the gene dose and secondly by increasing the dose using multi-copy vectors. Such a lack of response is discussed in terms of the concepts of metabolic control analysis. When these five enzymes, however, were simultaneously increased by a multi-copy vector carrying all five genes, a substantial elevation of the flux to tryptophan was observed. These findings revealed a new phenomenon, namely the more than additive effects on the flux of simultaneous elevations of several enzyme activities.

Investigations on the effects of hyperbaric oxygen on enzyme activity

1969 ◽  
Vol 47 (4) ◽  
pp. 400-402 ◽  
Author(s):  
Nicole Bégin-Heick ◽  
P. Hochstein ◽  
Gale B. Hill
Keyword(s):  
Enzyme Activity ◽  
Hyperbaric Oxygen ◽  
Enzyme Activities ◽  
Liver Tissue ◽  
In Vitro Assay ◽  
Vitro Assay

The ability of hyperbaric oxygen to produce lasting effects on enzyme activities was investigated. Mice were subjected to hyperbaric oxygen until they suffered sustained convulsions. The enzyme activities were then determined in brain and liver tissue. The results presented indicate that under these conditions of in vivo exposure and in vitro assay, hyperbaric oxygen does not affect permanently the activities of the enzymes which were examined.

Release of Platelet Factor 4 in Vivo during Intravascular Coagulation and in Thrombotic States

1968 ◽  
Vol 19 (03/04) ◽  
pp. 578-583 ◽  
Author(s):  
R Farbiszewski ◽  
S Niewiarowski ◽  
K Worowski ◽  
B Lipiński
Keyword(s):  
Coronary Thrombosis ◽  
Laboratory Diagnosis ◽  
Tolerance Test ◽  
Platelet Factor 4 ◽  
Thrombin Time ◽  
Significant Elevation ◽  
Platelet Factor ◽  
Thrombotic Diseases ◽  
Disseminated Intravascular Clotting

SummaryPlatelet factor 4 released from platelets into the circulating blood was determined using both the heparin thrombin time and paracoagulation methods. It has been found that thrombin injected intravenously into rabbits releases large amounts of this factor. Infusion of plasmin does not release this factor and this finding may be of importance for the differential diagnosis between disseminated intravascular clotting and primary fibrinolysis. PF4 is not released during the hyper coagulable condition induced by HgCl2 intoxication. Only small amounts of this factor are released after contact factor infusion.A significant elevation of extraplatelet PF4 was found in 23 patients with fresh coronary thrombosis and in 9 patients with thrombophlebitis and thromboembolic complications.The significance of the above findings for the pathogenesis, treatment and laboratory diagnosis of thrombotic diseases with particular reference to heparin tolerance test is discussed.

Animal Models and Alternatives in the Quality Control of Vaccines: Are In Vitro Methods or In Vivo Methods the Scientific Equivalent of the Emperor's New Clothes?

1995 ◽  
Vol 23 (1) ◽  
pp. 61-73
Author(s):  
Coenraad Hendriksen ◽  
Johan van der Gun
Keyword(s):  
Quality Control ◽  
Test Methods ◽  
In Vitro Test ◽  
Large Numbers ◽  
Alternative Approach ◽  
Inactivated Vaccines ◽  
Vitro Test

In the quality control of vaccine batches, the potency testing of inactivated vaccines is one of the areas requiring very large numbers of animals, which usually suffer significant distress as a result of the experimental procedures employed. This article deals with the potency testing of diphtheria and tetanus toxoids, two vaccines which are used extensively throughout the world. The relevance of the potency test prescribed by the European Pharmacopoeia monographs is questioned. The validity of the potency test as a model for the human response, the ability of the test to be standardised, and the relevance of the test in relation to the quality of the product are discussed. It is concluded that the potency test has only limited predictive value for the antitoxin responses to be expected in recipients of these toxoids. An alternative approach for estimating the potency of toxoid batches is discussed, in which a distinction is made between estimation of the immunogenic potency of the first few batches obtained from a seed lot and monitoring the consistency of the quality of subsequent batches. The use of animals is limited to the first few batches. Monitoring the consistency of the quality of subsequent batches is based on in vitro test methods. Factors which hamper the introduction and acceptance of the alternative approach are considered. Finally, proposals are made for replacement, reduction and/or refinement (the Three Rs) in the use of animals in the routine potency testing of toxoids.

Activation of the peptidergic neurosecretory system in Diphyllobothrium dendriticum (Cestoda: Pseudophyllidea)

Parasitology ◽  
1981 ◽  
Vol 83 (2) ◽  
pp. 243-247 ◽  
Author(s):  
Margaretha K. S. Gustafsson ◽  
Marianne C. Wikgren
Keyword(s):  
Neurosecretory Cells ◽  
Final Host ◽  
Fish Host ◽  
Neurosecretory System ◽  
Weak Reaction ◽  
Diphyllobothrium Dendriticum ◽  
Large Numbers ◽  
Short Times

SUMMARYThe activation of the peptidergic neurosecretory system in Diphyllobothrium dendriticum was studied following cultivation of plerocercoids for short times in vitro and in vivo. In the plerocercoid the neurosecretory cells gave a very weak reaction with paraldehyde fuchsin (PAF). After cultivation for 1 h large numbers of neurosecretory cells filled with PAF-positive granules were evident. The significance of the activation of the neurosecretory system during the transfer of the worm from the cold-blooded fish host to the warm-blooded final host is discussed.

scholarly journals Fatty acids in the placenta of Appropiate- versus small-for-gestational-age infants at term birth

Placenta ◽  
2021 ◽  
Author(s):  
Ariadna Gómez-Vilarrubla ◽  
Berta Mas-Pares ◽  
Marta Díaz ◽  
Sílvia Xargay-Torrent ◽  
Gemma Carreras-Badosa ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Gestational Age ◽  
Small For Gestational Age ◽  
Term Birth

Controlled Nano–Bio Interface of Functional Nanoprobes for in Vivo Monitoring Enzyme Activity in Tumors

ACS Nano ◽  
2019 ◽  
Author(s):  
Ziyan Sun ◽  
Kai Cheng ◽  
Yuyu Yao ◽  
Fengyu Wu ◽  
Jonathan Fung ◽  
...  
Keyword(s):  
Enzyme Activity ◽  
In Vivo Monitoring

scholarly journals Risk of pre-term births and major birth defects resulting from paternal intake of COVID-19 medications prior to conception

2020 ◽  
Vol 13 (1) ◽  
Author(s):  
Silvia Rizzi ◽  
Maarten J. Wensink ◽  
Rune Lindahl-Jacobsen ◽  
Lu Tian ◽  
Ying Lu ◽  
...  
Keyword(s):  
Cohort Study ◽  
Birth Outcomes ◽  
Birth Defects ◽  
Sperm Quality ◽  
The Other ◽  
Reproductive Age ◽  
Adverse Birth Outcomes ◽  
Term Birth ◽  
Large Numbers ◽  
Term Births

Abstract Objective With the ongoing COVID-19 pandemic, large numbers of people will receive one of the several medications proposed to treat COVID-19, including patients of reproductive age. Given that some medications have shown adverse effects on sperm quality, there might be a transgenerational concern. We aim at examining the association between drugs proposed to treat COVID-19 when taken by the father around conception and any pre-term birth or major birth defects in offspring in a nation-wide cohort study using Danish registry data. Offspring whose father filled at least one prescription of the following medications in the 3 months preceding conception were considered exposed: chloroquine, hydroxychloroquine, losartan, azithromycin, naproxen, dexamethasone and prednisone. Results For azithromycin and naproxen, large numbers of offspring were exposed (> 1800 offspring), and we found no association with adverse birth outcomes. For chloroquine, losartan and dexamethasone, exposure was intermediate (~ 900 offspring), and there was no statistically significant association with birth defects. For hydroxychloroquine and prednisone, exposure was limited (< 300 offspring). Our evidence suggests that azithromycin and naproxen are safe with respect to pre-term birth and birth defects. For the other drugs investigated larger exposures are needed for conclusive statements.

Nutrient uptake and enzyme activity of the preattachment goat embryo developed in vivo

1994 ◽  
Vol 41 (1) ◽  
pp. 204 ◽  
Author(s):  
D.K. Gardner ◽  
M. Lane ◽  
P.A. Batt
Keyword(s):  
Enzyme Activity ◽  
Nutrient Uptake
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