Dispersal patterns in a medium‐density Irish badger population: Implications for understanding the dynamics of tuberculosis transmission

European badgers (Meles meles) are group‐living mustelids implicated in the spread of bovine tuberculosis (TB) to cattle and act as a wildlife reservoir for the disease. In badgers, only a minority of individuals disperse from their natal social group. However, dispersal may be extremely important for the spread of TB, as dispersers could act as hubs for disease transmission. We monitored a population of 139 wild badgers over 7 years in a medium‐density population (1.8 individuals/km²). GPS tracking collars were applied to 80 different individuals. Of these, we identified 25 dispersers, 14 of which were wearing collars as they dispersed. This allowed us to record the process of dispersal in much greater detail than ever before. We show that dispersal is an extremely complex process, and measurements of straight‐line distance between old and new social groups can severely underestimate how far dispersers travel. Assumptions of straight‐line travel can also underestimate direct and indirect interactions and the potential for disease transmission. For example, one female disperser which eventually settled 1.5 km from her natal territory traveled 308 km and passed through 22 different territories during dispersal. Knowledge of badgers' ranging behavior during dispersal is crucial to understanding the dynamics of TB transmission, and for designing appropriate interventions, such as vaccination.     

Diabetes mellitus in people with schizophrenia,bipolar disorder and major depressive disorder: a systematic review and large scale meta‐analysis

Type 2 diabetes mellitus (T2DM) is highly predictive of cardiovascular diseases and can have particularly deleterious health impacts in people with severe mental illness (SMI), i.e. schizophrenia, bipolar disorder or major depressive disorder. This meta‐analysis aimed: a) to describe pooled frequencies of T2DM in people with SMI; b) to analyze the influence of demographic, illness and treatment variables as well as T2DM assessment methods; and c) to describe T2DM prevalence in studies directly comparing persons with each specific SMI diagnosis to general population samples. The trim and fill adjusted pooled T2DM prevalence among 438,245 people with SMI was 11.3% (95% CI: 10.0%‐12.6%). In antipsychotic‐naïve participants, the prevalence of T2DM was 2.9% (95% CI: 1.7%‐4.8%). There were no significant diagnostic subgroup differences. A comparative meta‐analysis established that multi‐episode persons with SMI (N=133,470) were significantly more likely to have T2DM than matched controls (N=5,622,664): relative risk, RR=1.85, 95% CI: 1.45‐2.37, p<0.001. The T2DM prevalence was consistently elevated in each of the three major diagnostic subgroups compared to matched controls. Higher T2DM prevalences were observed in women with SMI compared to men (RR=1.43, 95% CI: 1.20‐1.69, p<0.001). Multi‐episode (versus first‐episode) status was the only significant predictor for T2DM in a multivariable meta‐regression analysis (r²=0.52, p<0.001). The T2DM prevalence was higher in patients prescribed antipsychotics, except for aripriprazole and amisulpride. Routine screening and multidisciplinary management of T2DM is needed. T2DM risks of individual antipsychotic medications should be considered when making treatment choices.     

Correlation between Human Leukocyte Antigen Class II Alleles and HAI Titers Detected Post-Influenza Vaccination

Influenza is a major cause of morbidity and mortality. Despite vaccination, many elderly recipients do not develop a protective antibody response. To determine whether Human Leukocyte Antigen (HLA) alleles modulate seroprotection to influenza, a cohort of HLA class II-typed high-risk vaccine recipients was investigated. Haemagglutinin inhibition (HAI) titres were measured 14–40 days post-subunit vaccination. Seroprotection was defined as HAI titres reaching 40 or greater for all three vaccine strains. HLA-DRB1*04∶01 and HLA-DPB1*04∶01 alleles were detected at higher frequencies in seroprotected compared with non-seroprotected individuals. Thus, the presence of certain HLA class II alleles may determine the magnitude of antibody responses to influenza vaccination.     

Deletion of Snf1 Affects the Nutrient Response of Yeast and Resembles Mutations Which Activate the Adenylate Cyclase Pathway

We have isolated a snf1/ccr1 mutant of Saccharomyces cerevisiae which loses viability upon starvation and fails to accumulate glycogen in response to abrupt depletion of phosphate or glucose. A snf1 null mutant is sensitive to heat stress and starvation and fails to accumulate glycogen during growth in rich medium. The phenotypes of the snf1 mutants are those commonly associated with an overactivation of the adenylate cyclase pathway. Mutations in adenylate cyclase or RAS2 which decrease the level of cAMP in the cell moderate the snf1 phenotype. In contrast, a mutation in RAS2 (RAS2val19) which increases the level of cAMP or a mutation in the regulatory subunit (BCY1) of cAMP-dependent protein kinase which results in unregulated cAMP-dependent protein kinase activity accentuates the snf1 phenotype. However, the action of SNF1 in the stress response appears at least partly independent of cAMP-dependent protein kinase because a snf1 phenotype is observed in a strain that lacks all three of the genes that encode the catalytic subunits of cAMP-dependent protein kinase. SNF1 therefore acts at least in part through a cAMP-independent pathway.     

Bovine tuberculosis visible lesions in cattle culled during herd breakdowns: the effects of individual characteristics,trade movement and co-infection

Background

Bovine tuberculosis (bTB), caused by Mycobacterium bovis, remains a significant problem for livestock industries in many countries worldwide including Northern Ireland, where a test and slaughter regime has utilised the Single Intradermal Comparative Cervical Tuberculin (SICCT) test since 1959.We investigated the variation in post-mortem confirmation based on bTB visible lesion (VL) presence during herd breakdowns using two model suites. We investigated animal-level characteristics, while controlling for herd-level factors and clustering. We were interested in potential impacts of concurrent infection, and therefore we assessed whether animals with evidence of liver fluke infection (Fasciola hepatica; post-mortem inspection), M. avium reactors (animals with negative M. bovis-avium (b-a) tuberculin reactions) or Bovine Viral Diarrhoea Virus (BVDV; RT-PCR tested) were associated with bTB confirmation.

Results

The dataset included 6242 animals removed during the 14 month study period (2013–2015). bTB-VL presence was significantly increased in animals with greater b-a reaction size at the disclosing SICCT test (e.g. b-a?=?5-9 mm vs. b-a?= 0 mm, adjusted Odds ratio (aOR): 14.57; p?<?0.001). M. avium reactor animals (b-a?<?0) were also significantly more likely to disclose VL than non-reactor animals (b-a?= 0; aOR: 2.29; p?=?0.023). Animals had a greater probability of exhibiting lesions with the increasing number of herds it had resided within (movement; log-herds: aOR: 2.27–2.42; p?<?0.001), if it had an inconclusive penultimate test result (aOR: 2.84–3.89; p?<?0.001), and with increasing time between tests (log-time; aOR: 1.23; p?=?0.003). Animals were less likely to have VL if they were a dairy breed (aOR: 0.79; p?=?0.015) or in an older age-class (e.g. age-quartile 2 vs. 4; aOR: 0.65; p?<?0.001). Liver fluke or BVDV variables were not retained in either multivariable model as they were non-significantly associated with bTB-VL status (p?>?0.1).

Conclusions

Our results suggest that neither co-infection of liver fluke nor BVDV had a significant effect on the presence of VLs in this high-risk cohort. M. avium tuberculin reactors had a significantly increased risk of disclosing with a bTB lesion, which could be related to the impact of co-infection with M. avium subsp. paratuberculosis (MAP) affecting the performance of the SICCT however further research in this area is required. Movements, test history, breed and age were important factors influencing confirmation in high-risk animals.

     

Nikkomycin Z is a specific inhibitor of Saccharomyces cerevisiae chitin synthase isozyme Chs3 in vitro and in vivo.

Nikkomycin Z inhibits chitin synthase in vitro but does not exhibit antifungal activity against many pathogens. Assays of chitin synthase isozymes and growth assays with isozyme mutants were used to demonstrate that nikkomycin Z is a selective inhibitor of chitin synthase 3. The resistance of chitin synthase 2 to nikkomycin Z in vitro is likely responsible for the poor activity of this antibiotic against Saccharomyces cerevisiae.     

The Saccharomyces cerevisiae SRK1 gene, a suppressor of bcy1 and ins1, may be involved in protein phosphatase function.

The Saccharomyces cerevisiae SRK1 gene, when expressed on a low-copy shuttle vector, partially suppresses the phenotype associated with elevated levels of cyclic AMP-dependent protein kinase activity and suppresses the temperature-sensitive cell cycle arrest of the ins1 mutant. SRK1 is located on chromosome IV, 3 centimorgans from gcn2. A mutant carrying a deletion mutation in srk1 is viable. SRK1 encodes a 140-kDa protein with homology to the dis3+ protein from Schizosaccharomyces pombe. The ability of SRK1 to alleviate partially the defects caused by high levels of cyclic AMP-dependent protein kinase and the similarity of its encoded protein to dis3+ suggest that SRK1 may have a role in protein phosphatase function.