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Prevalence, distribution and risk factors for brucellosis infection in goat farms in Ningxiang, China
Get PDFBackground
In south China, goats are the major source of Brucellosis for human infection. However, there are few studies on the prevalence of and risk factors for goat brucellosis in south China. In this study, we conducted a cross-sectional study to investigate the herd prevalence, spatial distribution and relevant risk factors for goat brucellosis in Ningxiang county, south China. Commercial goat farms (n = 457) were randomly selected, and their disease status was ascertained by testing serum samples of chosen individuals using the Rose Bengal Test (screening test) and the Serum Agglutination Test (confirmatory test) in series. A farm with at least two positive individuals was defined as a case farm. Standardized questionnaires were used to collect information on management and hygiene practices in farms. A logistic model with a binomial outcome was built to identify risk factors for being seropositive.
Results
The true herd prevalence in commercial goat farms was 4.5% (95%CI: 0.2%-12.2%) and the townships in the centre of the county had higher herd prevalence. The risk factors associated with seropositive on local goat farms include “Introduction in the past 12 months” (OR= 61, 95%CI: 16-333), “Improperly disposal of the sick or dead goats” (OR= 33, 95%CI: 5-341) and “Poor hygiene in lambing pen” (OR= 25, 95%CI: 5-192).
Conclusions
These findings will aid in the development of control strategies of Brucellosis in south China and risk factors identified in this study should be taken into consideration when designing a control strategy
Asymmetric thinning of the cerebral cortex across the adult lifespan is accelerated in Alzheimer’s disease
Get PDFAging and Alzheimer’s disease (AD) are associated with progressive brain disorganization. Although structural asymmetry is an organizing feature of the cerebral cortex it is unknown whether continuous age- and AD-related cortical degradation alters cortical asymmetry. Here, in multiple longitudinal adult lifespan cohorts we show that higher-order cortical regions exhibiting pronounced asymmetry at age ~20 also show progressive asymmetry-loss across the adult lifespan. Hence, accelerated thinning of the (previously) thicker homotopic hemisphere is a feature of aging. This organizational principle showed high consistency across cohorts in the Lifebrain consortium, and both the topological patterns and temporal dynamics of asymmetry-loss were markedly similar across replicating samples. Asymmetry-change was further accelerated in AD. Results suggest a system-wide dedifferentiation of the adaptive asymmetric organization of heteromodal cortex in aging and AD
New Phytophthora species in clade 2a from the Asia-Pacific region including a re-examination of P. colocasiae and P. meadii
No full textFive new taxa from Phytophthora ITS clade 2a are described from Cinnamomum cassia plantations and adjacent waterways in Van Yen, Vietnam, disturbed rainforest in the Hela Province of Papua New Guinea and from disturbed forest on Christmas Island. Phylogenetic analyses were performed using data from nuclear regions (ITS, β-tubulin; heat shock protein 90) and mitochondrial regions (cytochrome c oxidase subunit 1; cytochrome c oxidase subunit 2; NADH dehydrogenase subunit 1; ribosomal protein L10). The molecular data supported recognition of three species: Phytophthora insulinativitatica, P. multibullata and P. x vanyenensis, and two informal taxa: P. sp. germisporangia and P. sp. awatangi. P. x vanyenensis appears to be a hybrid between P. mekongensis and an unknown species. P. multibullata and P. sp. germisporangia are phylogenetically close to P. citrophthora, but morphologically distinct. P. insulinativitatica is most closely related to P. botryosa, but has distinct morphology. P. sp. germisporangia and P. sp. awatangi were morphologically distinct and separated in the phylogeny based on mitochondrial sequences, but their nuclear sequences were identical. When comparing the sequences of these new species to that available on GenBank, it became evident that some of these species shared similarity with isolates submitted to GenBank under other species names. A re-evaluation of all P. meadii and P. colocasiae ITS sequence data identified an additional 7 putatively new species all isolated from Asia. The results support the view that many more Phytophthora species remain to be discovered in the Asia-Pacific region
As old as the hills: Pliocene palaeogeographical processes influence patterns of genetic structure in the widespread, common shrub Banksia sessilis
Get PDFThe impact of Quaternary glaciation on the development of phylogeographic structure in plant species is well documented. In unglaciated landscapes, phylogeographic patterns tend to reflect processes relating to persistence and stochasticity, yet other factors, associated with the palaeogeographical history of the landscape, including geomorphological events, can also have a significant influence. The unglaciated landscape of south‐western Western Australia is an ideal location to observe these ancient drivers of lineage diversification, with tectonic activity associated with the Darling Fault in the late Pliocene attributed to patterns of deep phylogeographic divergence in a widespread tree from this region. Interestingly, other species within this region have not shown this pattern and this palaeogeographical boundary therefore presents an opportunity to examine age and historical distribution of plant species endemic to this region. In this study, we assess patterns of genetic diversity and structure across 28 populations of the widespread shrub Banksia sessilis using three cpDNA markers and nine nuclear microsatellite markers. Sixteen cpDNA haplotypes were identified, comprising two major chloroplast DNA lineages that are estimated to have diverged in the Pliocene, approximately 3.3 million years ago. This timing coincides with major geomorphological processes in the landscape, including the separation of the Darling Plateau from the adjacent Swan Coastal Plain, as well as eustatic changes on the Swan Coastal Plain that are likely to have resulted in the physical isolation of historical plant lineages. Chloroplast lineages were broadly aligned with populations associated with older lateritic soils of the Darling Plateau and Geraldton sandplains or the younger sandy soils associated with the Swan Coastal Plain and Southern Coastline. This structural pattern of lateritic versus non‐lateritic division was not observed in the nuclear microsatellite data that identified three genetic clades that roughly corresponded to populations in the North, South, and Central portions of the distributions
The current situation of diagnosis and treatment of neuromyelitis optica spectrum disorder: Experience with 461 cases from a single centre in South China
No full textIn this study, we included 461 NMOSD patients at our hospital from January 2016 to June 2019 and got some results. Eight (1.9%) originally AQP4-IgG-seronegative patients were retested as seropositive. 221 patients (47.9%) did not receive immunosuppressive treatment within 3 month. The adult/child distribution was significantly different ( p = 0.001). Thirty-three patients (7.2%) had relapses after drug withdrawal, and fifteen of them had used drugs ≥3 years. The conclusion is that decision to treat with immunosuppression was made less often in children than in adults. Patients who took medication for a long time still need to be cautious of stopping using immunosuppression
Presymptomatic Dutch-Type hereditary cerebral amyloid Angiopathy-Related blood metabolite alterations
No full textBackground:Cerebral amyloid angiopathy (CAA) is one of the major causes of intracerebral hemorrhage and vascular dementia in older adults. Early diagnosis will provide clinicians with an opportunity to intervene early with suitable strategies, highlighting the importance of pre-symptomatic CAA biomarkers. Objective:Investigation of pre-symptomatic CAA related blood metabolite alterations in Dutch-type hereditary CAA mutation carriers (D-CAA MCs). Methods:Plasma metabolites were measured using mass-spectrometry (AbsoluteIDQ® p400 HR kit) and were compared between pre-symptomatic D-CAA MCs (n = 9) and non-carriers (D-CAA NCs, n = 8) from the same pedigree. Metabolites that survived correction for multiple comparisons were further compared between D-CAA MCs and additional control groups (cognitively unimpaired adults). Results:275 metabolites were measured in the plasma, 22 of which were observed to be significantly lower in theD-CAAMCs compared to D-CAA NCs, following adjustment for potential confounding factors age, sex, and APOE ε4 (p < 0.05). After adjusting for multiple comparisons, only spermidine remained significantly lower in theD-CAAMCscompared to theD-CAA NCs (p < 0.00018). Plasma spermidine was also significantly lower in D-CAA MCs compared to the cognitively unimpaired young adult and older adult groups (p < 0.01). Spermidinewas also observed to correlate with CSF Aβ40 (rs = 0.621, p = 0.024), CSF Aβ42 (rs = 0.714, p = 0.006), and brain Aβ load (rs = –0.527, p = 0.030). Conclusion:The current study provides pilot data on D-CAA linked metabolite signals, that also associated with Aβ neuropathology and are involved in several biological pathways that have previously been linked to neurodegeneration and dementia
Loophole or lifeline? The policy challenges of mines in care and maintenance
No full textCare and maintenance (C&M) refers to mines that have closed temporarily. This can be used disingenuously as a loophole to avoid mine closure, or legitimately as a lifeline with the view to recommence mining. This paper focusses on Australia, with a well-developed mining industry, a substantial mining legacy and a growing number of mines due to close. The aim of this paper is to understand and contextualise C&M as a policy challenge, identifying the barriers and constraints to recommence C&M mines and the opportunities and limitations of regulatory options to deliver positive outcomes. The method included policy document analysis followed by semi-structured interviews.
Results suggest C&M policies in Australia are few, unclear and their application limited by the high risk of C&M mines becoming abandoned. Existing policies are unable to address the complexities and vulnerabilities of mines in C&M and do not address the tension between the objective to mine and policy requirements to close mines. The findings suggest a tension between firmer regulation of C&M and a possible increased risk of abandonment. Further policy development for C&M could assist in avoiding future legacy mines but is unlikely to address the existing barriers that prevent mines in C&M from recommencing
Evaluation of electrocoagulation, flocculation, and sedimentation harvesting methods on microalgae consortium grown in anaerobically digested abattoir effluent
No full textMicroalgae dewatering is a major bottleneck for biomass production in a large-scale microalgal production system which accounts for 20–60% of production cost. In this study, three dewatering systems of electrocoagulation, flocculation, and pH-induced flocculation were evaluated for microalgal consortium grown in anaerobically digested abattoir effluent at pH 6.5 and 9.5. At the shortest time (15 min) and the highest current density (0.08 A cm−2), the highest microalgae recoveries of 78 and 84% were obtained with the corresponding power consumptions of 1.25 and 1.07 kWh kg−1 for cultures at pH 6.5 and 9.5. For microalgae suspension at pH 6.5, the highest biomass recovery of 77% was obtained when 100 mg L−1 of FeCl3·6H2O (after 15 min) or 100 mg L−1 of Al2(SO4)3·18H2O (after 30 min) was added. However, microalgal recoveries significantly increased when FeCl3·6H2O or Al2(SO4)3·18H2O was used with the culture at pH 9.5. pH-Induced experiments showed that cultures adjusted at pH 10.5 had 36% higher biomass recovery compared to that in cultures at pH 8.5 after 2 h. The results of this study showed that cultures at higher pH (9.5) had a better microalgae recovery in all dewatering systems than cultures at lower pH (6.5)
“Big girls don’t cry”: The effect of the experimenter’s sex and pain catastrophising on pain
No full textObjectives
The expression of pain in males and females involves complex socio-psychological mechanisms. Males may report lower pain to a female experimenter to appear strong, whereas females may report higher pain to a male experimenter to appear weak and to seek protection. However, evidence to support these stereotypes is inconclusive. Individuals who catastrophise about pain rate higher pain than those who do not. How pain catastrophising interacts with the effect of the experimenter’s sex on pain reports is yet to be explored. Thus, the aim of this study was to determine whether pain catastrophising moderated the effect of the experimenter’s sex on pain reports in healthy males and females.
Methods
Participants (n=60, 30 males) were assigned to one of four experimental conditions: males tested by male experimenters, males tested by female experimenters, females tested by male experimenters, and females tested by female experimenters. Participants completed the Pain Catastrophising Scale, and then sensitivity to heat and to blunt (pressure-pain threshold) and sharp stimuli was assessed on both forearms, and to high frequency electrical stimulation (HFS) administered to one forearm.
Results
Females reported lower pressure-pain thresholds than males irrespective of the experimenters’ sex. Females reported lower sharpness ratings to male than female experimenters only when the test stimuli were moderately or intensely sharp. Higher pain catastrophising scores were associated with higher sharpness ratings in females but not males. Additionally, higher pain catastrophising scores were associated with greater temporal summation of pain to HFS, and with lower pressure-pain thresholds in females who were tested by male experimenters.
Conclusions
These findings indicate that the experimenters’ sex and the participant’s pain catastrophising score influence pain reports, particularly in females. Awareness of these psychosocial factors is important in order to interpret pain responses in a meaningful way, especially when females are tested by male experimenters. A greater awareness of sex/gender role biases and their potential interaction with pain catastrophising may help researchers and clinicians to interpret pain reports in meaningful ways. In turn, this may help to improve delivery of treatments for patients with chronic pain
