A genetic and spatial Bayesian analysis of mastitis resistance

A nationwide health card recording system for dairy cattle was introduced in Norway in 1975 (the Norwegian Cattle Health Services). The data base holds information on mastitis occurrences on an individual cow basis. A reduction in mastitis frequency across the population is desired, and for this purpose risk factors are investigated. In this paper a Bayesian proportional hazards model is used for modelling the time to first veterinary treatment of clinical mastitis, including both genetic and environmental covariates. Sire effects were modelled as shared random components, and veterinary district was included as an environmental effect with prior spatial smoothing. A non-informative smoothing prior was assumed for the baseline hazard, and Markov chain Monte Carlo methods (MCMC) were used for inference. We propose a new measure of quality for sires, in terms of their posterior probability of being among the, say 10% best sires. The probability is an easily interpretable measure that can be directly used to rank sires. Estimating these complex probabilities is straightforward in an MCMC setting. The results indicate considerable differences between sires with regards to their daughters disease resistance. A regional effect was also discovered with the lowest risk of disease in the south-eastern parts of Norway.     

Resistance of Anhydrobiotic Aphelenchus avenae to Methyl Bromide Fumigation

The effect of methyl bromide (MB) was tested on active and anhydrobiotic Aphelenchus avenae. A. avenae was induced into anhydrobiosis by three different techniques. Both active and anhydrobiotic nematodes were subjected to 3,000 μ1 MB/liter air for 14 periods from 0 to 82 h. Anhydrobiotic nematodes were more resistant to fumigation than active nematodes, regardless of the technique used to induce anhydrobiosis. The percent survival decreased with increasing MB exposures (μ1 MB × h). For an LD₉₅ of 45,000-54,000 μ1/1 × h were required for active nematodes and >279,000 μ1/1 × h for anhydrobiotic nematodes.     

The Influence of Changes in Magnetic Variations and Light–Dark Cycle on Life-History Traits of Daphnia magna

Day–night cycle is the main zeitgeber (time giver) for biological circadian rhythms. Recently, it was suggested that natural diurnal geomagnetic variation may also be utilized by organisms for the synchronization of these rhythms. In this study, life-history traits in Daphnia magna were evaluated after short-term and multigenerational exposure to 16 h day/8 h night cycle, 32 h day/16 h night cycle, diurnal geomagnetic variation of 24 h, simulated magnetic variation of 48 h, and combinations of these conditions. With short-term exposure, the lighting mode substantially influenced the brood to brood period and the lifespan in daphnids. The brood to brood period, brood size, and body length of crustaceans similarly depended on the lighting mode during the multigenerational exposure. At the same time, an interaction of lighting mode and magnetic variations affected to a lesser extent brood to brood period, brood size, and newborn's body length. The influence of simulated diurnal variation on life-history traits in daphnids appeared distinctly as effects of synchronization between periods of lighting mode and magnetic variations during the multigenerational exposure. Newborn's body length significantly depended on the lighting regime when the periods of both studied zeitgebers were unsynchronized, or on the interaction of light regime with magnetic variations when the periods were synchronized. These results confirm the hypothesis that diurnal geomagnetic variation is an additional zeitgeber for biological circadian rhythms. Possible mechanisms for these observed effects are discussed. Bioelectromagnetics. © 2020 Bioelectromagnetics Society     

Time of day effect on balance performance,functional capacities and risk of fall in women with rheumatoid arthritis

ABSTRACT

Objective: This study explored the time of day effect of balance performance, functional capacities and risk of fall in three different times in patients with rheumatoid arthritis (RA) and the association between these variations and those of RA symptoms.

Methods: A “discontinual” protocol, composed of three test sessions, carried out at 6 am, 2 pm and 10 pm was set up, in order to investigate the time of day effect of balance performance, functional capacities, risk of fall, stiffness, range of motion, swollen and painful joints in women with RA.

Results: Time Up and Go Test (TUGT), Functional Reach Test (FRT) and tinetti test scores were significantly higher (p < .01) at 6 am and at 10 pm compared to 2 pm. Stiffness, range of motion, swollen and painful joints values were significantly higher (p < .01) at 6 am and at 10 pm compared to 2 pm. A significant difference was observed on the stiffness, range of motion and swollen joints values between 6 am and 10 pm that were higher at 6 am (p < .05).

Using Pearson’s coefficient, correlations were found between RA symptom values; and TUGT, FRT and Tinetti test scores.

Conclusion: Results showed a time of day effect of balance performance, functional capacities and risk of falls in women with RA. This variation indicates an alteration of performance at 6 am and 10 pm. Fluctuations of stiffness, limited range of motion, swollen and painful joints noted are concomitant to those of balance performance, functional capacities, and risk of fall.

Abbreviations: RA: rheumatoid arthritis; H&O questionnaire: Horne and Ostberg questionnaire; PSQI: Pittsburgh sleep quality index; HAQ: health assessment questionnaire; SF-36: the short form-36; WOMAC: Western Ontario and McMaster Universities Osteoarthritis Index; TUGT: Time Up and Go Test; FRT: Functional Reach Test     

Tampering with cancer chemoresistance by targeting the TGM2-IL6-autophagy regulatory network

Macroautophagy/autophagy is a well-established process involved in maintaining cellular homeostasis, but its role in cancer is complex and even controversial. Many studies have reported a correlative relationship between increased autophagy and evolving cancer cells under stress conditions such as nutrient or oxygen deprivation; however, there has been a lack of a plausible mechanistic link to properly target the autophagy process in the context of this microenvironment. We recently unveiled a positive regulatory loop involving TGM2 (transglutaminase 2)-NFKB/NF-κB signaling, IL6 and autophagy in cancer using mantle cell lymphoma (MCL) as a model system. These pathways are functionally connected to each other, thereby promoting malignant B cell survival and leading to enhanced lymphoma progression both in mice and in patients. Disruption of this network could provide an opportunity to increase the efficacies of current therapies and to reduce MCL drug resistance.     

Estimating survival of the shortfin mako Isurus oxyrinchus (Rafinesque) in the north-west Atlantic from tag-recapture data

Survival was estimated for shortfin mako Isurus oxyrinchus in the north-west Atlantic from tag-recapture data. The data used in this study were collected by the National Marine Fisheries Service Cooperative Shark Tagging Programme from 1962 to 2003. In total, 6309 shortfin mako sharks were tagged, of which 730 were recaptured. The high recapture rate of 11·6% for this species provided adequate recapture data to carry out survival analyses. Estimates of survival were generated with the computer software MARK, which provided a means for estimating parameters from tagged animals when they were recaptured. The results of several models are presented with various combinations of constant and time-specific survival and recovery rates. A parametric bootstrap and the median variance inflation factor ( ) approach were used to test the fit of the general model to the data. The estimated indicated a very good model fit. The models with time invariant survival rate had the most support from the data and no group or time period effects were found. Recovery rate ( f ) appeared to increase from 0·043 in the early years to 0·056 in the later years. The nominal survival rate of 0·59 year⁻¹ was adjusted with an estimated tag-shedding rate of 0·26 year⁻¹ to generate a final corrected annual survival estimate of 0·79 with a 95% CI of 0·71–0·87.     

Survival, growth and feeding of vendace, Coregonus albula (L.), larvae in net enclosures

Vendace, Coregonus albula (L.), larvae reared in net enclosures anchored in the littoral zone of Lake Ylä-Enonvesi, eastern Finland, were observed for a period of 44 days in order to determine the effects of density on mortality, growth and feeding of the larvae. The ratio of newly-hatched fish to their food was regulated by controlling the number of fish stocked into the enclosures. Prey animals were expected to move freely in and out of the enclosures. The effect of nylon mesh (500 μm) on the penetration of zooplankters into the enclosures was negligible. The influence of possible starvation was determined by analysing the growth of the larvae, their Fulton condition factor, the instantaneous amount of food ingested, and the food composition in their guts. All these indicators were inversely correlated with larval density. Vendace larvae were found to be resistant to mortality from direct starvation. At all densities the survival rate was over 60%. At the time of complete yolk absorption, there was no increase in mortality.