Demonstration of VIP receptors in B cells of the pancreas by quantitative ultrastructural autoradiography

Using quantitative electron microscopic autoradiography we demonstrated the existence of specific VIP receptors in B cells of the pancreatic islets. The presence of those receptors strongly suggests that the neuromediator can induce insulin release by direct stimulation of B cells.     

Effect of Facilitation of Local Stakeholder Groups on Equity in Neonatal Survival; Results from the NeoKIP Trial in Northern Vietnam

Background

To operationalize the post-MDG agenda, there is a need to evaluate the effects of health interventions on equity. The aim of this study is to evaluate the effect on equity in neonatal survival of the NeoKIP trial (ISRCTN44599712), a population-based, cluster-randomized intervention trial with facilitated local stakeholder groups for improved neonatal survival in Quang Ninh province in northern Vietnam.

Methods

Semi-structured interviews were conducted with all mothers experiencing neonatal mortality and a random sample of 6% of all mothers with a live birth in the study area during the study period (July 2008-June 2011). Multilevel regression analyses were performed, stratifying mothers according to household wealth, maternal education and mother’s ethnicity in order to assess impact on equity in neonatal survival.

Findings

In the last year of study the risk of neonatal death was reduced by 69% among poor mothers in the intervention area as compared to poor mothers in the control area (OR 0.31, 95% CI 0.15–0.66). This pattern was not evident among mothers from non-poor households. Mothers with higher education had a 50% lower risk of neonatal mortality if living in the intervention area during the same time period (OR 0.50, 95% CI 0.28–0.90), whereas no significant effect was detected among mothers with low education.

Interpretation

The NeoKIP intervention promoted equity in neonatal survival based on wealth but increased inequity based on maternal education.     

In vivo nonlinear optical imaging to monitor early microscopic changes in a murine cutaneous squamous cell carcinoma model

Early detection of cutaneous squamous cell carcinoma (cSCC) can enable timely therapeutic and preventive interventions for patients. In this study, in vivo nonlinear optical imaging (NLOI) based on two‐photon excitation fluorescence (TPEF) and second harmonic generation (SHG), was used to non‐invasively detect microscopic changes occurring in murine skin treated topically with 7,12‐dimethylbenz(a)anthracene (DMBA). The optical microscopic findings and the measured TPEF‐SHG index show that NLOI was able to clearly detect early cytostructural changes in DMBA treated skin that appeared clinically normal. This suggests that in vivo NLOI could be a non‐invasive tool to monitor early signs of cSCC.

In vivo axial NLOI scans of normal murine skin (upper left), murine skin with preclinical hyperplasia (upper right), early clinical murine skin lesion (lower left) and late or advanced murine skin lesion (lower right).     

Effect of storage time and pretreatment on seed germination of the threatened coniferous species Fokienia hodginsii

We report the effects of storage time and pretreatment on seed germination of Fokienia hodginsii. Lower mean germination was observed in seeds stored for 2 years (6.41 ± 1.23 seeds/replicate) compared with those stored for 1 year (8.52 ± 1.06 seeds/replicate). Seeds collected from a southern location had statistically higher mean germination (9.67 ± 1.28 seeds/replicate) than those collected from a northern location (7.99 ± 1.36 seeds/replicate). Higher mean T₅₀ was observed in seeds stored for 2 years (37.02 ± 4.43 days) compared with those stored for 1 year (30.69 ± 5.06 days). Mean germination of untreated fresh seeds was 9.97 ± 1.34 seeds/replicate and that of treated fresh seeds in 60°C water was 12.95 ± 1.24 seeds/replicate. Fresh seeds treated with 50°C and 70°C water had a significantly lower mean germination compared with untreated seeds and seeds treated in 60°C water. Mean T₅₀ was lowest in seeds treated with 60°C water.     

Isolation of Butyl 2,3‐Dihydroxybenzoate From Paenibacillus elgii HOA73 Against Fusarium oxysporum f.sp. Lycopersici

Here we report for the first time the isolation of butyl 2,3‐dihydroxybenzoate (B2,3DB) from the novel antagonistic bacterium Paenibacillus elgii HOA73 and its activity against Fusarium oxysporum f.sp. lycopersici (FOL). In this study, the bacterial strain P. elgii HOA73 was isolated from soil and identified via 16S rRNA gene sequence analysis. The isolate demonstrated significant antagonism towards several plant pathogens including FOL. Our results showed the bacterial culture filtrate of P. elgii HOA73 to be highly active, inhibiting 86.1% of the growth of FOL at 50% concentration. Similarly, the bacterial crude extract of P. elgii HOA73 at 2 mg significantly inhibited FOL growth by 72.5%. An antifungal compound was purified from the bacterial crude extract of P. elgii HOA73 through different chromatographic techniques and was identif‐ied as butyl 2,3‐dihydroxybenzoate (B2,3DB) based on nuclear magnetic resonance and liquid chromatography‐mass spectrometry analyses. B2,3DB displayed potent antifungal properties, inhibiting FOL growth by 83.2% when used at 0.6 mg. The minimum inhibitory concentration of B2,3DB to inhibit any visible mycelial growth of FOL was 32 μg ml^?1. All FOL conidia displayed an absence of germination or degradation when treated with 32 μg ml^?1 B2,3DB after 8 or 24 h, respectively. Therefore, our results clearly demonstrated B2,3DB, as well as P. elgii HOA73, as potential biological control agents for the management of FOL.     

Determinants of Influenza Transmission in South East Asia: Insights from a Household Cohort Study in Vietnam

To guide control policies, it is important that the determinants of influenza transmission are fully characterized. Such assessment is complex because the risk of influenza infection is multifaceted and depends both on immunity acquired naturally or via vaccination and on the individual level of exposure to influenza in the community or in the household. Here, we analyse a large household cohort study conducted in 2007–2010 in Vietnam using innovative statistical methods to ascertain in an integrative framework the relative contribution of variables that influence the transmission of seasonal (H1N1, H3N2, B) and pandemic H1N1pdm09 influenza. Influenza infection was diagnosed by haemagglutination-inhibition (HI) antibody assay of paired serum samples. We used a Bayesian data augmentation Markov chain Monte Carlo strategy based on digraphs to reconstruct unobserved chains of transmission in households and estimate transmission parameters. The probability of transmission from an infected individual to another household member was 8% (95% CI, 6%, 10%) on average, and varied with pre-season titers, age and household size. Within households of size 3, the probability of transmission from an infected member to a child with low pre-season HI antibody titers was 27% (95% CI 21%–35%). High pre-season HI titers were protective against infection, with a reduction in the hazard of infection of 59% (95% CI, 44%–71%) and 87% (95% CI, 70%–96%) for intermediate (1∶20–1∶40) and high (≥1∶80) HI titers, respectively. Even after correcting for pre-season HI titers, adults had half the infection risk of children. Twenty six percent (95% CI: 21%, 30%) of infections may be attributed to household transmission. Our results highlight the importance of integrated analysis by influenza sub-type, age and pre-season HI titers in order to infer influenza transmission risks in and outside of the household.     

A review of the genus Pimpla Fabricius, 1804 (Hymenoptera: Ichneumonidae: Pimplinae) from Vietnam with descriptions of two new species

The ichneumonid wasp genus Pimpla Fabricius, 1804 is reviewed for the first time from Vietnam. Two new species are described: Pimpla lexuanhuei sp. nov. from Phu Tho Province and Pimpla chuyansinensis sp. nov. from Dak Lak Province. Five further species are recorded as new for Vietnam: P. bilineata (Cameron), P. cameronii Dalla Torre, P. ereba Cameron, P. flavipalpis Cameron, and P. laothoe Cameron. Pimpla instigator (Fabricius, 1793), a junior synonym of P. rufipes (Miller, 1759), previously recorded from Vietnam, was re-identified as P. laothoe and therefore is excluded from the ichneumonid fauna of Vietnam. A key to all ten species listed in this paper is also compiled.     

Sequence‐based SNP genotyping in durum wheat

Marker development for marker‐assisted selection in plant breeding is increasingly based on next‐generation sequencing (NGS). However, marker development in crops with highly repetitive, complex genomes is still challenging. Here we applied sequence‐based genotyping (SBG), which couples AFLP^®‐based complexity reduction to NGS, for de novo single nucleotide polymorphisms (SNP) marker discovery in and genotyping of a biparental durum wheat population. We identified 9983 putative SNPs in 6372 contigs between the two parents and used these SNPs for genotyping 91 recombinant inbred lines (RILs). Excluding redundant information from multiple SNPs per contig, 2606 (41%) markers were used for integration in a pre‐existing framework map, resulting in the integration of 2365 markers over 2607 cM. Of the 2606 markers available for mapping, 91% were integrated in the pre‐existing map, containing 708 SSRs, DArT markers, and SNPs from CRoPS technology, with a map‐size increase of 492 cM (23%). These results demonstrate the high quality of the discovered SNP markers. With this methodology, it was possible to saturate the map at a final marker density of 0.8 cM/marker. Looking at the binned marker distribution (Figure 2), 63 of the 268 10‐cM bins contained only SBG markers, showing that these markers are filling in gaps in the framework map. As to the markers that could not be used for mapping, the main reason was the low sequencing coverage used for genotyping. We conclude that SBG is a valuable tool for efficient, high‐throughput and high‐quality marker discovery and genotyping for complex genomes such as that of durum wheat.     

Cloning, expression, purification, and properties of an endoglucanase gene (glycosyl hydrolase family 12) from Aspergillus niger VTCC-F021 in Pichia pastoris

A gene coding for an endoglucanase (EglA), of the glycosyl hydrolase family 12 and derived from Aspergillus niger VTCC-F021, was cloned and sequenced. The cDNA sequence, 717 bp, and its putative endoglucanase, a 238 aa protein with a predicted molecular mass of 26 kDa and a pI of 4.35, exhibited 98.3-98.7% and 98.3-98.6% identities, respectively, with cDNA sequences and their corresponding endoglucanases from Aspergillus niger strains from the GenBank. The cDNA was overexpressed in Pichia pastoris GS115 under the control of an AOX1 promoter with a level of 1.59 U/ml culture supernatant, after 72 h of growth in a YP medium induced with 1% (v/v) of methanol. The molecular mass of the purified EglA, determined by SDS-PAGE, was 33 kDa, with a specific activity of 100.16 and 19.91 U/mg toward 1% (w/v) of beta-glucan and CMC, respectively. Optimal enzymatic activity was noted at a temperature of 55°C and a pH of 5. The recombinant EglA (rEglA) was stable over a temperature range of 30- 37°C and at pH range of 3.5-4.5. Metal ions, detergents, and solvents tested indicated a slightly inhibitory effect on rEglA activity. Kinetic constants (K(m), V(max), k(cat), and k(cat)/ K(m)) determined for rEglA with beta-glucan as a substrate were 4.04 mg/ml, 102.04 U/mg, 2,040.82 min-1, and 505.05, whereas they were 10.17 mg/ml, 28.99 U/mg, 571.71 min-1, and 57.01 with CMC as a substrate, respectively. The results thus indicate that the rEglA obtained in this study is highly specific toward beta-glucan. The biochemical properties of rEglA make it highly valuable for downstream biotechnological applications, including potential use as a feed enzyme.