DNA barcoding of South Africa’s ornamental freshwater fish – are the names reliable?

Trade in freshwater ornamental fish in South Africa is currently regulated by a ‘blacklist’ to prevent potentially invasive taxa from establishing in the country. Because its effective implementation requires accurate identification, the aim of the present study was to test whether DNA barcoding is a useful tool to identify freshwater fishes in the South African pet trade. A total of 351 aquarium fish specimens, representing 185 traded taxa, were sequenced for the mitochondrial COI barcoding marker in 2011 and 2012. Lake Malawi cichlids were treated as a single group due to a lack of resolution in their COI marker, resulting in a data set of 137 successfully sequenced taxa. The Barcode Of Life Database (BOLD) and GenBank were used for taxonomic assignment comparisons. The genetic identification matched the scientific name inferred from the trade name for 60 taxa (43.8%) using BOLD, and for 67 taxa (48.9%) using GenBank. A genetic ID could not be assigned in 47 (34.3%) cases using BOLD and in 37 cases (27%) using GenBank. Whereas DNA barcoding can be a useful tool to help identify imported freshwater fishes, it requires further development of publicly available databases to become a reliable means of identification.     

Long-term survival in patients treated with ruxolitinib for myelofibrosis: COMFORT-I and -II pooled analyses

Background

Myelofibrosis (MF) is associated with a variety of burdensome symptoms and reduced survival compared with age-/sex-matched controls. This analysis evaluated the long-term survival benefit with ruxolitinib, a Janus kinase (JAK)1/JAK2 inhibitor, in patients with intermediate-2 (int-2) or high-risk MF.

Methods

This was an exploratory analysis of 5-year data pooled from the phase 3 COMFORT-I and -II trials. In both trials, patients could cross over to ruxolitinib from the control group (COMFORT-I, placebo; COMFORT-II, best available therapy). All continuing patients in the control groups crossed over to ruxolitinib by the 3-year follow-up. Overall survival (OS; a secondary endpoint in both trials) was evaluated using pooled intent-to-treat data from patients randomized to ruxolitinib or the control groups. OS was also evaluated in subgroups stratified by baseline anemia and transfusion status at week 24.

Results

A total of 528 patients were included in this analysis; 301 were originally randomized to ruxolitinib (COMFORT-I, n?=?155; COMFORT-II, n?=?146) and 227 to control (n?=?154 and n?=?73, respectively). The risk of death was reduced by 30% among patients randomized to ruxolitinib compared with patients in the control group (median OS, 5.3 vs 3.8 years, respectively; hazard ratio [HR], 0.70 [95% CI, 0.54–0.91]; P?=?0.0065). After correcting for crossover using a rank-preserving structural failure time (RPSFT) method, the OS advantage was more pronounced for patients who were originally randomized to ruxolitinib compared with patients who crossed over from control to ruxolitinib (median OS, 5.3 vs 2.3 years; HR [ruxolitinib vs RPSFT], 0.35 [95% CI, 0.23–0.59]). An analysis of OS censoring patients at the time of crossover also demonstrated that ruxolitinib prolonged OS compared with control (median OS, 5.3 vs 2.4 years; HR [ruxolitinib vs censored at crossover], 0.53 [95% CI, 0.36–0.78]; P?=?0.0013). The survival benefit with ruxolitinib was observed irrespective of baseline anemia status or transfusion requirements at week 24.

Conclusions

These findings support ruxolitinib treatment for patients with int-2 or high-risk MF, regardless of anemia or transfusion status. Further analyses will be important for exploring ruxolitinib earlier in the disease course to assess the effect on the natural history of MF.

Trial registration

ClinicalTrials.gov identifiers, NCT00952289 and NCT00934544.

     

Childbirth Moderates the Genetic and Environmental Influences on BMI in Adult Twins

We report a study of the moderating role that the number of childbirths has on the genetic and environmental influences on BMI variation. We used a classical twin design with a sample of 704 adult female twins (334 monozygotic and 370 dizygotic). A gene–environment interaction (G × E) model was applied to estimate the moderating effects of childbearing. Results show that age and number of children exert a significant positive main effect on BMI. Furthermore, we found significant moderating effects of childbearing, with a larger number of children associated with an increased sensitivity to environmental factors.     

华西银腊梅挥发油化学成分的研究

用水蒸气蒸馏法提取华西银腊梅挥发油,并用气相色谱-质谱(GC-MS)联用技术对其挥发油的化学成分进行分析,结果共鉴定了其中的39种成分,所鉴定成分含量约占总检出量的87.83%。其化学成分主要为(Z,Z)-9,12-十八碳二烯酸甲酯(9.00%),壬醛(5.83%),二十一烷(5.69%),二十烷(5.08%),辛炔酸(4.50%),2,6,10,15-四甲基十七烷(3.93%),(Z)-6-十八烯酸甲酯(3.65%),3,8-二甲基十一烷(3.52%),1-十六碳炔(3.31%),肉豆蔻酸(2.86%),月桂醛(2.81%),壬酸(2.23%),5,6,7,7α-四氢-4,4,7α三甲基-2(4H)-苯并呋喃酮(2.18%)等。     

The diagnostic approach to early Alzheimer's disease. What are we talking about? Conceptual considerations

Progress in knowledge of the physiopathology of Alzheimer's disease over the last few decades has allowed much earlier diagnosis, even before the onset of clinical symptoms. Although the use of biomarkers is still far from being widespread and cannot be recommended outside research settings, their potential use has led to a review of the diagnostic criteria employed in the last few years. Among other criteria, asymptomatic and prodromal phases have been definitively incorporated into the spectrum of the disease and have been redefined. In future, the possibility of an earlier and more accurate diagnosis will allow the application of treatments acting in these phases, delaying progression to more advanced stages or even halting the disease before clinical manifestations develop. Currently, such treatments are still far from being a reality and interest in biomarkers centers on research since their detection could allow standardization of the samples used in clinical trials and exclusion of individuals showing signs of prodromal disease but who will never develop the disease.     

Emerging complexity in the denitrification regulatory network of Bradyrhizobium japonicum

Bradyrhizobium japonicum is a Gram-negative soil bacterium symbiotically associated with soya bean plants, which is also able to denitrify under free-living and symbiotic conditions. In B. japonicum, the napEDABC, nirK, norCBQD and nosRZDYFLX genes which encode reductases for nitrate, nitrite, nitric oxide and nitrous oxide respectively are required for denitrification. Similar to many other denitrifiers, expression of denitrification genes in B. japonicum requires both oxygen limitation and the presence of nitrate or a derived nitrogen oxide. In B. japonicum, a sophisticated regulatory network consisting of two linked regulatory cascades co-ordinates the expression of genes required for microaerobic respiration (the FixLJ/FixK2 cascade) and for nitrogen fixation (the RegSR/NifA cascade). The involvement of the FixLJ/FixK2 regulatory cascade in the microaerobic induction of the denitrification genes is well established. In addition, the FNR (fumarase and nitrate reduction regulator)/CRP(cAMP receptor protein)-type regulator NnrR expands the FixLJ/FixK2 regulatory cascade by an additional control level. A role for NifA is suggested in this process by recent experiments which have shown that it is required for full expression of denitrification genes in B. japonicum. The present review summarizes the current understanding of the regulatory network of denitrification in B. japonicum.     

Immune and viral profile from tolerance to hepatitis B surface antigen clearance: a longitudinal study of vertically hepatitis B virus-infected children on combined therapy

The aim of the study was to investigate longitudinally hepatitis B virus (HBV)-specific T-cell reactivity and viral behavior versus treatment response in tolerant children during combined antiviral therapy. Twenty-three children with infancy-acquired hepatitis B (HBeAg(+)) belonging to a published pilot study of 1-year treatment with lamivudine/alpha interferon (IFN-α) were investigated. Five seroconverted to anti-HBs (responders). Nine were HLA-A2(+) (4 responders and 5 nonresponders). Mutations within the HBV core gene were determined at baseline in liver and in serial serum samples by direct sequencing at baseline; during treatment week 2 (TW2), TW9, TW28, and TW52; and after follow-up week 24 (FUW24) and FUW52. HBV-specific reactivity was evaluated by T-cell proliferation with 16 HBV core 20-mer overlapping peptides and by HLA-A2-restricted core(18-27) pentamer staining and CD8(+) IFN-γ enzyme-linked immunospot (ELISPOT) assay. HBV core-specific T-cell proliferative and CD8 responses were more vigorous and broader among responders than among nonresponders at TW28 and TW52, while the number of mutations within HBV core gene immunodominant epitopes was lower at TW28 and was negatively associated with HBV-specific T-cell proliferative responses at both time points. The HBV DNA viral load was negatively associated with HBV-specific T-cell proliferative and CD8 responses during treatment, especially at TW28. Treatment-induced transition from immunotolerance to HBV immune control is characterized by the emergence of efficient virus-specific immune responses capable of restraining mutations and preventing viral evasion.