Variation in barbiturate sleeping time in mice 3. Strain × environment interactions

1986 ◽  
Vol 20 (4) ◽  
pp. 307-312 ◽  
Author(s):  
D. P. Lovell

Environmental factors such as diet, bedding material and temperature at the time of testing affected a 'model' pharmacological response - pentobarbitone sleeping time - differentially in a range of inbred strains. These results are probably explained by variations in the responses of the strains to constituents of the diets and bedding materials used in the experiments. Differences in the results between experiments suggest that there are also fluctuations in the composition of the diets and bedding materials over time. Strain × environment interactions such as those found here may explain differences in strain rankings between experiments. They would also account for some of the variability in results found between laboratories and within a laboratory over time.

1986 ◽  
Vol 20 (2) ◽  
pp. 85-90 ◽  
Author(s):  
D. P. Lovell

A set of 23 inbred strains of mice was tested for their sleeping time under sodium pentobarbitone anaesthetic. Highly significant strain differences were found. Estimates of the proportion of the variation accounted for by genetic differences ranged from 28% to 42%. In general, males slept longer than females but the size of the sex differences was not consistent across strains. Sleeping times on different test days also varied, indicating that environmental factors were affecting the results. A specially designed experiment failed to detect any differences in within-strain variation.


1986 ◽  
Vol 20 (2) ◽  
pp. 91-96 ◽  
Author(s):  
D. P. Lovell

The effect of some environmental factors on the pentobarbitone sleeping time (PST) in inbred strains of mice has been investigated. Age, dose level and fasting before the test significantly altered the PST while the source of the drug and regular handling of the mice had no effect. None of these factors affected strains differentially. Unsystematic effects such as litter differences contributed only a small proportion of the total variation in the experiments. The strain rankings were different from those obtained in some previous experiments. The effects of some of the environmental factors on the PST did not always agree with previous work. The implications of these results for the design of similar experiments and the relevance of baseline values in laboratory animals are discussed.


2021 ◽  
Vol 64 (3) ◽  
pp. 843-855
Author(s):  
Jeff P. Jaderborg ◽  
Mindy J. Spiehs ◽  
Bryan L. Woodbury ◽  
Alfredo DiCostanzo ◽  
David B. Parker

HighlightsAromatic compounds generated 72.6% of the total odor activity values (OAVs) over time.Cold treatments had significantly lower total OAVs than hot treatments regardless of the age of the bedded pack.Abstract. Beef cattle producers are beginning to raise cattle in confinement facilities such as slatted-floor barns, hoop barns, and mono-slope facilities. Hoop and mono-slope facilities typically use bedding packs as part of their manure management system, with crop residues being the most commonly used bedding material. This study was conducted to determine the effects of bedding material, i.e., corn stover (CS), bean stover (BS), wheat straw (WS), or pine wood chips (PC), and environmental ambient temperature, i.e., cold (15°C) or hot (30°C), on the concentrations of odorous volatile organic compounds (VOCs) in air samples collected in the headspace above lab-scale bedded packs over a 42-day period. Total aromatic compounds, sulfide compounds, straight-chain fatty acids (SCFAs), and branched-chain fatty acids (BCFAs) were measured and used to calculate total odor activity values (OAVs) for each bedding and temperature effect. No significant three-way interactions for bedding material × ambient temperature × age of bedded pack were observed. Significant bedding material × ambient temperature interactions were observed for total aromatic compounds and total sulfide compounds (p = 0.0455 and p = 0.0083, respectively). The concentration of total aromatic compounds was greater for all hot treatments compared to cold treatments, with hot-CS and hot-WS bedding types (389.83 and 365.5 ng L-1, respectively) significantly (p < 0.05) greater than all other bedding types, while total aromatic compounds were lowest (87.09 ng L-1) for BS across cold treatments. Total sulfide compounds from cold-PC (51.69 ng L-1) were significantly (p = 0.0143) greater than all other treatments. Within hot treatments, total sulfide compounds were similar across all bedding materials. Total SCFAs for both cold and hot treatments decreased significantly from weeks 4 to 6. Total SCFA concentrations within weeks were significantly (p < 0.0001) greater for WS and CS compared to BS and PC but similar across bedding materials at week 6. Total BCFA concentrations from bedded packs containing CS and WS were significantly (p < 0.0001) higher at week 4 compared to concentrations from bedded packs containing BS or PC. As bedded packs aged, total BCFA concentrations for all bedding materials were similar at week 6. Total OAVs decreased over time for both hot and cold treatments, although cold treatments had significantly (p < 0.0001) lower total OAVs regardless of the age of the bedded pack. Aromatic compounds generated 72.6% of the total OAV over the 42-day study. Bedding types BS and PC had the lowest total OAVs across all weeks. The results indicate that feedlot operators maintaining bedded pack facilities will achieve the greatest overall odor reduction when using BS or PC bedding material, no matter the ambient temperature. Keywords: Bedding, Beef, Odor, Volatile organic compounds.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yisong Huang ◽  
Shaoyong Su ◽  
Harold Snieder ◽  
Frank Treiber ◽  
Gaston Kapuku ◽  
...  

AbstractIncreased arterial stiffness measured by pulse wave velocity (PWV) is an important parameter in the assessment of cardiovascular risk. Our previous longitudinal study has demonstrated that carotid-distal PWV showed reasonable stability throughout youth and young adulthood. This stability might be driven by genetic factors that are expressed consistently over time. We aimed to illustrate the relative contributions of genetic and environmental factors to the stability of carotid-distal PWV from youth to young adulthood. We also examined potential ethnic differences. For this purpose, carotid-distal PWV was measured twice in 497 European American (EA) and African American (AA) twins, with an average interval time of 3 years. Twin modelling on PWV showed that heritability decreased over time (62–35%), with the nonshared environmental influences becoming larger. There was no correlation between the nonshared environmental factors on PWV measured at visit 1 and visit 2, with the phenotypic tracking correlation (r = 0.32) completely explained by shared genetic factors over time. Novel genetic influences were identified accounting for a significant part of the variance (19%) at the second measurement occasion. There was no evidence for ethnic differences. In summary, novel genetic effects appear during development into young adulthood and account for a considerable part of the variation in PWV. Environmental influences become larger with age for PWV.


2020 ◽  
Vol 987 ◽  
pp. 93-98
Author(s):  
Jun Yan Liu ◽  
Jin Guo Wang ◽  
Yun Hai Yu ◽  
Na Wang

Biodegradable vascular stent is mainly made of materials that can be naturally decomposed. After implantation into human blood vessels, the vascular stent can be continuously degraded over time and eventually disappear completely after the treated blood vessels are healed and support from the vascular stent is not needed. The vascular stent materials used in clinic should have good biocompatibility, which mainly involves blood compatibility and cell compatibility. In terms of cell compatibility, the influence of materials on cell growth should be observed. The various biological materials should have good anticoagulant character, so as to reduce the tendency of thrombosis and avoid the occurrence of various risk events in clinical treatment.


2020 ◽  
Author(s):  
Tatyana Dobreva ◽  
David Brown ◽  
Jong Hwee Park ◽  
Matt Thomson

AbstractAn individual’s immune system is driven by both genetic and environmental factors that vary over time. To better understand the temporal and inter-individual variability of gene expression within distinct immune cell types, we developed a platform that leverages multiplexed single-cell sequencing and out-of-clinic capillary blood extraction to enable simplified, cost-effective profiling of the human immune system across people and time at single-cell resolution. Using the platform, we detect widespread differences in cell type-specific gene expression between subjects that are stable over multiple days.SummaryIncreasing evidence implicates the immune system in an overwhelming number of diseases, and distinct cell types play specific roles in their pathogenesis.1,2 Studies of peripheral blood have uncovered a wealth of associations between gene expression, environmental factors, disease risk, and therapeutic efficacy.4 For example, in rheumatoid arthritis, multiple mechanistic paths have been found that lead to disease, and gene expression of specific immune cell types can be used as a predictor of therapeutic non-response.12 Furthermore, vaccines, drugs, and chemotherapy have been shown to yield different efficacy based on time of administration, and such findings have been linked to the time-dependence of gene expression in downstream pathways.21,22,23 However, human immune studies of gene expression between individuals and across time remain limited to a few cell types or time points per subject, constraining our understanding of how networks of heterogeneous cells making up each individual’s immune system respond to adverse events and change over time.


2019 ◽  
Vol 9 (6) ◽  
pp. 146 ◽  
Author(s):  
Sheerin ◽  
Kovalchick ◽  
Overstreet ◽  
Rappaport ◽  
Williamson ◽  
...  

: Genes, environmental factors, and their interplay affect posttrauma symptoms. Although environmental predictors of the longitudinal course of posttraumatic stress disorder (PTSD) symptoms are documented, there remains a need to incorporate genetic risk into these models, especially in youth who are underrepresented in genetic studies. In an epidemiologic sample tornado-exposed adolescents (n = 707, 51% female, Mage = 14.54 years), trajectories of PTSD symptoms were examined at baseline and at 4-months and 12-months following baseline. This study aimed to determine if rare genetic variation in genes previously found in the sample to be related to PTSD diagnosis at baseline (MPHOSPH9, LGALS13, SLC2A2), environmental factors (disaster severity, social support), or their interplay were associated with symptom trajectories. A series of mixed effects models were conducted. Symptoms decreased over the three time points. Elevated tornado severity was associated with elevated baseline symptoms. Elevated recreational support was associated with lower baseline symptoms and attenuated improvement over time. Greater LGLAS13 variants attenuated symptom improvement over time. An interaction between MPHOSPH9 variants and tornado severity was associated with elevated baseline symptoms, but not change over time. Findings suggest the importance of rare genetic variation and environmental factors on the longitudinal course of PTSD symptoms following natural disaster trauma exposure.


1984 ◽  
Vol 33 (1) ◽  
pp. 130-143 ◽  
Author(s):  
Greta Robertson ◽  
Michael D. Lebowitz

2014 ◽  
Vol 17 (2) ◽  
pp. 169 ◽  
Author(s):  
Isabel Ortega Diego ◽  
Antony Fake ◽  
Matthias Stahl ◽  
Lembit Rägo

Purpose. The aim of this work was to determine the number and type of active pharmaceutical ingredient (API) quality deficiencies in API Master Files (APIMFs) as submitted to the World Health Organization (WHO) Prequalification of Medicines Programme (PQP). Methods. We conducted a retrospective review of API quality deficiencies identified following the assessment of new APIMFs for non-sterile APIs during a 6-year period from 1 January 2007 to 31 December 2012. All deficiencies were collected, classified and quantified according to the Common Technical Document (CTD) sections and subsections and as groups of commonly raised questions. Results. There were 5446 deficiencies collected from 159 APIMF deficiency letters by CTD section, by selected CTD subsections and by selected CTD subsections and year. More than 50% of the total number of deficiencies related to the manufacturing sections of the CTD, followed by deficiencies concerning the impurities, the API specification and the stability sections of the CTD.  A pattern of API deficiencies across the different CTD subsections and over time was identified. Conclusions. The most frequent critical deficiencies were related to how the specific manufacturing process and the key materials used, in particular the API starting material, impact the API impurities content. The number and pattern of APIMF deficiencies did not change over time. The results are compared to the findings in similar studies as reported by the United States Food and Drug Administration (USFDA), the European Directorate for the Quality of Medicines (EDQM) and the European Medicines Agency (EMA) and similarities and differences are discussed. Our findings highlight the need for greater guidance and technical assistance for API manufacturers submitting APIMFs to the PQP. This article is open to POST-PUBLICATION REVIEW. Registered readers (see “For Readers”) may comment by clicking on ABSTRACT on the issue’s contents page.


Sign in / Sign up

Export Citation Format

Share Document