Activation of Aedes aegypti prophenoloxidase-3 and its role in the immune response against entomopathogenic fungi

Serine protease cascade-mediated melanization is an important innate immune response in insects and crustaceans, which involves the proteolytic activation of prophenoloxidase (PPO). In this study, we investigated the role of Aedes aegypti PPO3 in antifungal immune defence. We expressed and purified recombinant PPO3 (rPPO3) in Escherichia coli and demonstrated that rPPO3 was activated by ethanol and, to a lesser extent, by cetylpyridinium chloride. In the presence of Cu²⁺ , rPPO3 exhibited enzyme activity. Immunoblot results revealed that the rPPO3 was cleaved by the haemolymph from immune-challenged mosquitoes or purified Ostrinia furnacalis serine protease 105 in vitro. The cleaved rPPO3 converted dopamine to toxic intermediates that killed fungal conidia of Beauveria bassiana in vitro. In mosquitoes challenged with Be. bassiana, cleavage of rPPO3 produced a 50 kDa phenoloxidase (PO) fragment. Further analysis revealed that the survival rate of mosquitoes with fungal infection increased significantly following injection of rPPO3 into the haemocoel. Taken together, our results suggest that proteolytic cleavage of the mosquito PPO3 plays an important role in the antifungal immune response. This has led to a better understanding of the mechanism of PPO activation in the mosquito and the role of melanization in the antifungal immune response.

Genomic innovations, transcriptional plasticity and gene loss underlying the evolution and divergence of two highly polyphagous and invasive Helicoverpa pest species

BACKGROUND

Helicoverpa armigera and Helicoverpa zea are major caterpillar pests of Old and New World agriculture, respectively. Both, particularly H. armigera, are extremely polyphagous, and H. armigera has developed resistance to many insecticides. Here we use comparative genomics, transcriptomics and resequencing to elucidate the genetic basis for their properties as pests.

RESULTS

We find that, prior to their divergence about 1.5 Mya, the H. armigera/H. zea lineage had accumulated up to more than 100 more members of specific detoxification and digestion gene families and more than 100 extra gustatory receptor genes, compared to other lepidopterans with narrower host ranges. The two genomes remain very similar in gene content and order, but H. armigera is more polymorphic overall, and H. zea has lost several detoxification genes, as well as about 50 gustatory receptor genes. It also lacks certain genes and alleles conferring insecticide resistance found in H. armigera. Non-synonymous sites in the expanded gene families above are rapidly diverging, both between paralogues and between orthologues in the two species. Whole genome transcriptomic analyses of H. armigera larvae show widely divergent responses to different host plants, including responses among many of the duplicated detoxification and digestion genes.

CONCLUSIONS

The extreme polyphagy of the two heliothines is associated with extensive amplification and neofunctionalisation of genes involved in host finding and use, coupled with versatile transcriptional responses on different hosts. H. armigera's invasion of the Americas in recent years means that hybridisation could generate populations that are both locally adapted and insecticide resistant.

A gyro-stabilized platform leveling loop for marine gravimeter

An ultra-low-frequency platform leveling loop based on a mixed sensitivity H^∞ approach, which considers both the system bandwidth and response speed, was designed and applied to a prototype, two-axis gyro-stabilized platform marine gravimeter CHZ-II. The instrument was developed for regional surveys in deep ocean areas where high-resolution gravity measurements with accuracy 1 mGal are required. Horizontal accelerations in the surge and sway directions are suppressed about 60 dB in the frequency range 0.05 to 0.5 Hz. This typically improves the quality of the gravity data before any processing corrections. The time required for stabilizing the platform at the beginning of a survey line or course change is about 3 min, which improves the data collection efficiency. In May 2015, the first test was conducted in open sea conditions aboard the Chinese State Oceanic Administration's R/V Xiangyanghong 10. Sixteen traverses were run in the South China Sea to evaluate the loop performance. Platform motion tracks and gravity data from the survey were of satisfactory quality. According to analyses of 16 sets of calculated errors, the root mean square repeatability of the pitch and roll off-level angles were less than 10 and 20 arc sec, respectively, with a horizontal acceleration of about 50 Gal. Errors derived from the inability of the platform to maintain perfect sensor leveling during the survey cruise were less than 0.3 mGal.

An association analysis between psychophysical characteristics and genome-wide gene expression changes in human adaptation to the extreme climate at the Antarctic Dome Argus

Genome-wide gene expression measurements have enabled comprehensive studies that integrate the changes of gene expression and phenotypic information to uncover their novel associations. Here we reported the association analysis between psychophysical phenotypes and genome-wide gene expression changes in human adaptation to one of the most extreme climates on Earth, the Antarctic Dome Argus. Dome A is the highest ice feature in Antarctica, and may be the coldest, driest and windiest location on earth. It is considered unapproachable due to its hostile environment. In 2007, a Chinese team of 17 male explorers made the expedition to Dome A for scientific investigation. Overall, 133 psychophysical phenotypes were recorded, and genome-wide gene expression profiles from the blood samples of the explorers were measured before their departure and upon their arrival at Dome A. We found that mood disturbances, including tension (anxiety), depression, anger and fatigue, had a strong, positive, linear relationship with the level of a male sex hormone, testosterone, using the Pearson correlation coefficient (PCC) analysis. We also demonstrated that significantly lowest-level Gene Ontology groups in changes of gene expression in blood cells with erythrocyte removal were consistent with the adaptation of the psychophysical characteristics. Interestingly, we discovered a list of genes that were strongly related to significant phenotypes using phenotype and gene expression PCC analysis. Importantly, among the 70 genes that were identified, most were significantly related to mood disturbances, where 42 genes have been reported in the literature mining, suggesting that the other 28 genes were likely novel genes involved in the mood disturbance mechanism. Taken together, our association analysis provides a reliable method to uncover novel genes and mechanisms related to phenotypes, although further studies are needed.

A meta-analysis of fast track surgery for patients with gastric cancer undergoing gastrectomy

INTRODUCTION

This meta-analysis evaluated the safety and efficacy of fast track surgery (FTS) for patients with gastric cancer undergoing gastrectomy.

METHODS

Randomised controlled trials (RCTs) published between 1 January 1995 and 21 June 2013 comparing FTS with conventional perioperative care for patients with gastric cancer undergoing gastrectomy were identified in the PubMed, Embase™ and Cochrane Library databases, and were analysed systematically using RevMan software (Nordic Cochrane Centre, Copenhagen, Denmark).

RESULTS

Seven RCTs (524 patients) were analysed. Compared with conventional perioperative care, FTS treatment with/without laparoscopy was associated with shorter postoperative hospitalisation, less hospitalisation expenditure (both p<0.00001), less pain and better quality of life. Short-term morbidity and readmission rates did not differ between treatments. No incidents of death occurred during the short-term follow-up period.

CONCLUSIONS

In patients with gastric cancer undergoing gastrectomy, the FTS pathway reduces the length and cost of postoperative hospitalisation while maintaining short-term morbidity, readmission and mortality rates comparable with those of conventional care.

[Investigation on the causes of increased hepatitis E cases reported in Guizhou province]

OBJECTIVE

To analyze causes of growing hepatitis E (HE) cases reported in Guizhou province, and probe into existing problems faced by medical institutions in diagnosis of clinical and laboratory-confirmed cases, for the purpose of improving the quality of HE surveillance system.

METHODS

Six hospitals reporting greater HE cases from 2007 to 2011 were pinpointed, whose reported cases rose suddenly in 2011. Such cases were investigated by means of impatient medical record review, results of laboratory test and clinician interview.

RESULTS

136 of the 354 reported HE cases investigated were found compliant with the diagnostic criteria of HE with an accordance rate of 38.42%. Difference of the HE diagnostic accordance rate among individual years, hospitals and reporting departments was statistically significant. Such rate of hospital reports was found to be the lowest in 2011, ranging from 0 to 18.18% respectively; HE cases reported by non-infectious departments accounted for 61.30% of total cases reported, with its accordance rate considerably below the infectious departments (8.29%). HE positive cases and HE positive rate in 2011 were significantly higher than that of preceding years.

CONCLUSION

Such increase of reported HE cases in 2011 in the province was mostly attributable to more HE laboratory tests made by the hospitals, yet the accordance rates were lower than satisfactory. In this regard, the medical institutions in question were advised to enhance their competency training for HE diagnosis and case report quality.

A meta-analysis of fast track surgery for patients with gastric cancer undergoing gastrectomy

INTRODUCTION

This meta-analysis evaluated the safety and efficacy of fast track surgery (FTS) for patients with gastric cancer undergoing gastrectomy.

METHODS

Randomised controlled trials (RCTs) published between 1 January 1995 and 21 June 2013 comparing FTS with conventional perioperative care for patients with gastric cancer undergoing gastrectomy were identified in the PubMed, Embase™ and Cochrane Library databases, and were analysed systematically using RevMan software (Nordic Cochrane Centre, Copenhagen, Denmark).

RESULTS

Seven RCTs (524 patients) were analysed. Compared with conventional perioperative care, FTS treatment with/without laparoscopy was associated with shorter postoperative hospitalisation, less hospitalisation expenditure (both p<0.00001), less pain and better quality of life. Short-term morbidity and readmission rates did not differ between treatments. No incidents of death occurred during the short-term follow-up period.

CONCLUSIONS

In patients with gastric cancer undergoing gastrectomy, the FTS pathway reduces the length and cost of postoperative hospitalisation while maintaining short-term morbidity, readmission and mortality rates comparable with those of conventional care.

[Study on the epidemiologic characteristic of Brucella melitensis isolated in Guizhou province in 2010-2012]

OBJECTIVE

To understand the genetic and epidemiologic characteristic of Brucella (B.) melitensis strains isolated in Guizhou province in 2010-2012.

METHODS

B. genus specific BCSP31-PCR and species-specific AMOS-PCR were used to identify the bacteria strain, while the identified strains were analyzed under MLVA-16 and cluster analysis of B. melitensis strains. The strains were isolated from Guizhou and other provinces.

RESULTS

Six B. melitensis strains were identified as B. melitensis using the BCSP31-PCR and AMOS-PCR. Data from the MLVA-16 analysis revealed the differences of repeated numbers at parts of the VNTR locus in the six strains isolated in Guizhou province. The six strains from Guizhou province and 105 B. melitensis strains from other province could be divided into 72 MLVA types(MT). Strain ZY and ZA from Guizhou province were typed as MT63, and LL3, LL4 and LL11 were typed as MT67, while strain SQ was typed as MT72. Data from the clustering analysis showed that ZY,ZA, LL3, LL4 and LL9 were most closely clustered with B. melitensis isolates from Yunnan, Fujian and Guangdong provinces, but strain SQ was genetically remote from other strains.

CONCLUSION

PCR methods, combined with MLVA-16, identified the six B. melitensis strains isolated in Guizhou province in 2010-2012 as B. melitensis biovar 3, with the genetic diversity of the strains showed. Six strains were closely related to the B. melitensis strains from Yunnan, Fujian and Guangdong provinces. The results of this study provided scientific basis for the control and prevention of Brucellosis in Guizhou province.

Two biomarker-directed randomized trials in European and Chinese patients with nonsmall-cell lung cancer: the BRCA1-RAP80 Expression Customization (BREC) studies

BACKGROUND

In a Spanish Lung Cancer Group (SLCG) phase II trial, the combination of BRCA1 and receptor-associated protein 80 (RAP80) expression was significantly associated with outcome in Caucasian patients with nonsmall-cell lung cancer (NSCLC). The SLCG therefore undertook an industry-independent collaborative randomized phase III trial comparing nonselected cisplatin-based chemotherapy with therapy customized according to BRCA1/RAP80 expression. An analogous randomized phase II trial was carried out in China under the auspices of the SLCG to evaluate the effect of BRCA1/RAP80 expression in Asian patients.

PATIENTS AND METHODS

Eligibility criteria included stage IIIB-IV NSCLC and sufficient tumor specimen for molecular analysis. Randomization to the control or experimental arm was 1 : 1 in the SLCG trial and 1 : 3 in the Chinese trial. In both trials, patients in the control arm received docetaxel/cisplatin; in the experimental arm, patients with low RAP80 expression received gemcitabine/cisplatin, those with intermediate/high RAP80 expression and low/intermediate BRCA1 expression received docetaxel/cisplatin, and those with intermediate/high RAP80 expression and high BRCA1 expression received docetaxel alone. The primary end point was progression-free survival (PFS).

RESULTS

Two hundred and seventy-nine patients in the SLCG trial and 124 in the Chinese trial were assessable for PFS. PFS in the control and experimental arms in the SLCG trial was 5.49 and 4.38 months, respectively [log rank P = 0.07; hazard ratio (HR) 1.28; P = 0.03]. In the Chinese trial, PFS was 4.74 and 3.78 months, respectively (log rank P = 0.82; HR 0.95; P = 0.82).

CONCLUSION

Accrual was prematurely closed on the SLCG trial due to the absence of clinical benefit in the experimental over the control arm. However, the BREC studies provide proof of concept that an international, nonindustry, biomarker-directed trial is feasible. Thanks to the groundwork laid by these studies, we expect that ongoing further research on alternative biomarkers to elucidate DNA repair mechanisms will help define novel therapeutic approaches.

TRIAL REGISTRATION

NCT00617656/GECP-BREC and ChiCTR-TRC-12001860/BREC-CHINA.

Differential effect of MMSET mRNA levels on survival to first-line FOLFOX and second-line docetaxel in gastric cancer

Background:

Breast cancer susceptibility gene 1 (BRCA1) expression differentially affects outcome to platinum- and taxane-based chemotherapy. Mediator of DNA damage checkpoint protein 1 (MDC1), p53-binding protein 1 (53BP1), multiple myeloma SET domain (MMSET) and ubiquitin-conjugating enzyme 9 (UBC9) are involved in DNA repair and could modify the BRCA1 predictive model.

Methods:

Mediator of DNA damage checkpoint protein 1, 53BP1, MMSET and UBC9 mRNA were assessed in gastric tumours from patients in whom BRCA1 levels had previously been determined.

Results:

In vitro chemosensitivity assay, MMSET levels were higher in docetaxel-sensitive samples. In a separate cohort, survival was longer in those with low MMSET (12.3 vs 8.8 months; P=0.04) or UBC9 (12.4 vs 8.8 months; P=0.01) in patients receiving only folinic acid, fluorouracil (5-FU) and oxaliplatin (FOLFOX). Conversely, among patients receiving second-line docetaxel, longer survival was associated with high MMSET (19.1 vs 13.9 months; P=0.003). Patients with high MMSET and BRCA1 attained a median survival of 36.6 months, compared with 13.9 months for those with high BRCA1 and low MMSET (P=0.003). In the multivariate analyses, low MMSET (hazard ratio (HR), 0.59; P=0.04) and low UBC9 (HR, 0.52; P=0.01) levels were markers of longer survival to first-line FOLFOX, whereas palliative surgery (HR, 2.47; P=0.005), low BRCA1 (HR, 3.17; P=0.001) and low MMSET (HR, 2.52; P=0.004) levels were markers of shorter survival to second-line docetaxel.

Conclusions:

Breast cancer susceptibility gene 1, MMSET and UBC9 can be useful for customising chemotherapy in gastric cancer patients.

[Evaluation on the effects of prevention and control programs regarding typhoid fever and paratyphoid fever in Guizhou province, from 2007 to 2012]

OBJECTIVE

This study was to evaluate the effects of prevention and control regarding programs on typhoid fever and paratyphoid fever, in Guizhou province, from 2007 to 2012, to provide evidence for the improvement of related programs.

METHODS

Data on typhoid fever and paratyphoid including information on epidemics, individual, cases, measures for prevention and control programs taken and relative government documents were collected and analyzed in Guizhou province, from 2007 to 2012. Information related to the average annual incidence, nature of outbreaks, time span before confirmed diagnosis was made, unit which carried the case report, proportion of laboratory confirmed diagnosed cases and case-management were compared between 2007-2009 and 2010-2012 descriptively while chi-square test with Excel and EpiInfo software were used for data analysis.

RESULTS

In the period of 2007-2009, a total of 5 978 typhoid fever and paratyphoid fever cases were reported in Guizhou province with the average yearly incidence as 5.29/100 000. In the period of 2010-2012, 2 765 cases were reported with the average yearly incidence as 2.57/100 000. When compared to the former, data from the latter period showed that the average yearly incidence had declined 51.31% in all the prefectures. There were still some outbreaks appeared but the total number of cases involved reduced 87.50%. The time span before the confirmation of diagnosis became shorter but the difference was not statistically significant (χ² = 0.08, P = 0.99). Number of cases reported by hospitals at county or above had 11.51% of increase while those cases reported at the township hospitals or below decreased for 61.47% . The proportion of laboratory diagnosed cases increased 23.63%. Rates of timeliness on cards being filled in, input and audited showed increase of 8.44%, 6.76% and 2.40% respectively.

CONCLUSION

Successful measures for prevention and control on typhoid fever and paratyphoid fever had been remarkably taken in Guizhou province, but the potential risk of outbreaks still existed in some areas, suggesting that health education and surveillance programs including laboratory diagnosis, should be strengthened.