Dihydrocryptopine

In the crystal structure of the title compound [systematic name: 6,7-dimeth­oxy-12-methyl-16,18-dioxa-12-aza­tetra­cyclo­[12.7.0.0^4,9.0^15,19]henicosa-1(21),4,6,8,14,19-hexaen-3-ol], C₂₁H₂₅NO₅, the benzene rings exhibits a dihedral angle of 14.95 (4)°. In the crystal, mol­ecules are linked by pairs of O—H⋯O hydrogen bonding into inversion dimers. These dimers are further connected by C—H⋯O inter­actions.

Alanyl-tRNA synthetase mutation in a family with dominant distal hereditary motor neuropathy

OBJECTIVE

To identify a new genetic cause of distal hereditary motor neuropathy (dHMN), which is also known as a variant of Charcot-Marie-Tooth disease (CMT), in a Chinese family.

METHODS

We investigated a Chinese family with dHMN clinically, electrophysiologically, and genetically. We screened for the mutations of 28 CMT or related pathogenic genes using an originally designed microarray resequencing DNA chip.

RESULTS

Investigation of the family history revealed an autosomal dominant transmission pattern. The clinical features of the family included mild weakness and wasting of the distal muscles of the lower limb and foot deformity, without clinical sensory involvement. Electrophysiologic studies revealed motor neuropathy. MRI of the lower limbs showed accentuated fatty infiltration of the gastrocnemius and vastus lateralis muscles. All 4 affected family members had a heterozygous missense mutation c.2677G>A (p.D893N) of alanyl-tRNA synthetase (AARS), which was not found in the 4 unaffected members and control subjects.

CONCLUSION

An AARS mutation caused dHMN in a Chinese family. AARS mutations result in not only a CMT phenotype but also a dHMN phenotype.

Polymorphic microsatellite loci for Japanese Spanish mackerel (Scomberomorus niphonius)

We isolated and characterized 21 polymorphic microsatellite loci in Japanese Spanish mackerel (Scomberomorus niphonius) using a (GT)(13)-enriched genomic library. Forty individuals were collected from Qingdao, China. We found 3 to 24 alleles per locus, with a mean of 8.8. The observed and expected heterozygosities ranged from 0.263 to 0.975 and from 0.385 to 0.946, with means of 0.655 and 0.685, respectively. Deviation from Hardy-Weinberg proportions was detected at three loci. Two loci showed evidence for null alleles. These microsatellite markers will be useful for population genetic analysis of Japanese Spanish mackerel.

Blood pressure and obesity among adolescents: a school-based population study in China

BACKGROUND

There is little information regarding the obesity epidemical situation and risk factors of childhood hypertension (HTN) in China. The present study aimed to determine the prevalence of HTN/prehypertension (PHTN), as well as the associated risk factors, among adolescents in Changsha city, China.

METHODS

A total of 88,974 adolescents from 49 middle schools in Changsha city between 12 and 17 years of age were examined during 2009. Body weight, height, and blood pressure (BP) were measured in all adolescents. HTN and PHTN were defined according to sex- and age-specific Chinese reference data. Overweight and obesity were also defined according to sex- and age-specific Chinese reference data.

RESULTS

It was determined that the prevalence of PHTN and HTN were 7.2 and 3.1%, respectively. Furthermore, 14.6% of male adolescents were overweight and 7.0% were obese, whereas 8.6% of female adolescents were overweight and 2.9% were obese. The risk ratio (RR) of HTN were significantly higher in overweight (RR: 2.8, 95% confidence interval (CI): 2.6-3.2) and obese (RR: 8.7, 95% CI: 8.1-9.5) adolescents adjusted for age, sex, and height.

CONCLUSIONS

Chinese reference data were used to evaluate BP and body mass index (BMI) of children and adolescents. Higher prevalence of HTN was associated with higher BMI percentiles. Being overweight or obese markedly increased the risk of both HTN and PHTN among adolescents between 12 and 17 years of age in Changsha city, China.

Ectopic expression of glucagon receptor in skeletal muscles improves glucose homeostasis in a mouse model of diabetes

AIMS/HYPOTHESIS

Excessive secretion of glucagon partially contributes to the development of diabetic hyperglycaemia. However, complete blocking of glucagon action will lead to adverse effects, since glucagon exerts certain beneficial effects via its receptor in many organs. We aimed to study the effects of a 'decoy receptor' for circulating glucagon on modulating beta cell function and glucose homeostasis in mice by over-producing the glucagon receptor (GCGR) in skeletal muscles.

METHODS

We generated transgenic mice in which the expression of Gcgr is driven by the muscle specific creatine kinase (Mck) promoter, and assessed the effects of glucagon on the modulation of glucose homeostasis under conditions of extremes of glucose influx or efflux.

RESULTS

Mck/Gcgr mice showed increased circulating levels of glucagon and insulin, resulting in an unchanged ratio of glucagon-to-insulin. The levels of hepatic glucose-6-phosphatase (G6PC) and fructose-1,6-bisphosphatase (F1,6P2ase) were significantly decreased, whereas the phosphorylation level of pancreatic cAMP-response-element-binding-protein (CREB) was significantly increased in these transgenic mice. Under basal conditions, the mice displayed normal blood glucose levels and unchanged glucose tolerance and insulin sensitivity when compared with their age-matched wild-type (WT) littermates. However, following multiple low-dose streptozotocin injections, Mck/Gcgr mice exhibited a delay in the onset of hyperglycaemia compared with the WT controls. This was associated with preserved beta cell mass and beta cell secretory capacity in response to glucose challenge.

CONCLUSIONS/INTERPRETATION

We suggest that mild and chronic hyperglucagonaemia, through a strategy involving neutralising peripheral glucagon action, provides beneficial effects on beta cell function and glucose homeostasis. Mck/Gcgr mice thus represent a novel mouse model for studying the physiological effects of glucagon.

Microelectronic-sensing assay to detect presence of Verotoxins in human faecal samples

AIMS

 To develop a novel Vero cell assay that implements a real-time cell electronic sensing (RT-CES) system for the determination of the presence of verotoxin-producing Escherichia coli (VTEC). The assay overcomes the major drawbacks in conventional Vero cell assay, for example, labour-intensive and time-consuming.

METHODS AND RESULTS

 Cells were grown onto the surfaces of microelectronic sensors that are integrated into the bottom surfaces of the microtiter plate. Cellular viability was monitored in real-time and quantified based on changes in the sensor's electrical impedance. For cell viability measurement, the data generated on the RT-CES system correlated well with those obtained by the Vero cell assay for Verotoxins. To assess cytotoxicity, test cells growing on microelectronic sensors were treated with either supernatant from pure cultures, or stool samples. The specific neutralizing antibodies of VT1 and VT2 were used to identify specific toxins in the samples.

CONCLUSIONS

 The RT-CES assay provides a sensitive measurement comparable to conventional crystal violet assay. The assay has been successfully and specifically used to identify VTEC in human faecal samples.

SIGNIFICANCE AND IMPACT OF THE STUDY

 The RT-CES assay significantly shortens the testing time from 48 to 72 h required by the crystal violet assay to only 15 h with automated operation.

Analysis of differentially expressed proteins involved in hand, foot and mouth disease and normal sera

We implemented 2-D DIGE technology on proteins prepared from serum obtained from children with hand, foot and mouth disease (HFMD) and controls, to study the differentially expressed proteins in control and HFMD serum samples. Proteins found to be differentially expressed were identified with matrix-assisted laser desorption/ionization time-of-flight/ time-of-flight mass spectrometry (MALDI-TOF/TOF MS) analysis. We identified 30 proteins from mild HFMD samples and 39 proteins from severe HFMD samples, compared with the normal controls. 25 proteins among them (14 up-regulated and 11 down-regulated proteins) are found in both HFMD groups. Classification analysis and protein-protein interaction map showed that they associate with multiple functional groups, including transporter activity and atalytic activity. These findings build up a comprehensive profile of the HFMD proteome and provide a useful basis for further analysis of the pathogenic mechanism and the regulatory network of HFMD.

High-fidelity, 160 fs, 5 μJ pulses from an integrated Yb-fiber laser system with a fiber stretcher matching a simple grating compressor

Although femtosecond microjoule Yb-fiber systems are attractive because of a straightforward power scalability, they inherently suffer from a lowered pulse fidelity as a result of complex dispersion and nonlinearity management. Here, we present an integrated Yb-fiber system delivering high-fidelity microjoule pulses compressible down to 160 fs. The system uses a dispersion compensating fiber stretcher that is specially designed to match the dispersion of a 1480 lines/mm grating compressor. Performance analysis suggests the further possibility of scaling the pulse energy to tens of microjoules without pulse quality deterioration using this dispersion management scheme.

Comparison of swab transport media for recovery of Listeria monocytogenes from environmental samples

Environmental monitoring is recognized as an important strategy for controlling Listeria monocytogenes in food processing facilities. Samples are taken by swabbing environmental surfaces, and the swabs are immersed in a medium for transport to the laboratory. In this study, buffered peptone water (BPW), Dey-Engley neutralizing broth (DE), neutralizing buffer (NB), Letheen broth (LE), and newly described MCC buffer (MCC) were evaluated as transport media for recovery of sanitizer-stressed L. monocytogenes from inoculated swabs. After storage at 4°C, the media performed similarly, but at 25°C relative recovery efficiency from the inoculated sponges was DE > LE > BPW > MCC > NB. Recoveries from stainless steel surfaces followed similar trends. MCC, DE, and NB were compared for L. monocytogenes recovery in the presence of Escherichia coli, Enterococcus faecalis, Lactobacillus plantarum, Pseudomonas fluorescens, and Listeria innocua. After 4°C storage, all population levels changed little; after 25°C storage, DE allowed the best growth of L. monocytogenes regardless of other species present. MCC, DE, and NB performed similarly for recovery of L. monocytogenes from an artificial milk biofilm and for recovery of Listeria spp. from swabs obtained from a meat processing facility. Transport medium formulation, time and temperature of swab storage, and coexistence of other species affect recovery of sanitizer-stressed L. monocytogenes from environmental swabs. The study confirms the need to maintain 4°C storage conditions during swab transport.

Stability of the Framingham Nutritional Risk Score and its component nutrients over 8 years: the Framingham Nutrition Studies

BACKGROUND/OBJECTIVES

Diet quality indices are increasingly used in nutrition epidemiology as dietary exposures in relation to health outcomes. However, literature on the long-term stability of these indices is limited. We aimed to assess the stability of the validated Framingham Nutritional Risk Score (FNRS) and its component nutrients over 8 years, as well as the validity of the follow-up FNRS.

SUBJECTS/METHODS

Framingham Offspring/Spouse Study women and men (n=1734) aged 22-76 years were evaluated over 8 years. Individuals' nutrient intake and nutritional risk scores were assessed using 3-day dietary records administered at baseline (1984-1988) and at follow-up (1992-1996). Agreement between baseline and follow-up FNRS and nutrient intakes was evaluated by Bland-Altman method; stability was assessed using intra-class correlation (ICC) and weighted Kappa statistics. The effect of diet quality (as assessed by the FNRS) on cardiometabolic risk factors was evaluated using analysis of covariance.

RESULTS

Modest changes from baseline (15%) were observed in nutrient intake. The stability coefficients for the FNRS (ICC: women, 0.49; men, 0.46; P<0.0001) and many nutrients (ICC 0.3) were moderate. Over half of the women and men (58%) remained in the same or contiguous baseline and follow-up quartile of the FNRS and few (3-4%) shifted >1 quartile. The FNRS was directly associated with body mass index in women (P<0.01) and high-density lipoprotein cholesterol among both women (P<0.001) and men (P<0.01).

CONCLUSIONS

The FNRS and its constituent nutrients remained relatively stable over 8 years of follow-up. The stability of diet quality has implications for prospective epidemiological investigations.

Beam-target double-spin asymmetry A{LT} in charged pion production from deep inelastic scattering on a transversely polarized {3}He target at 1.4<Q{2}<2.7 GeV{2}

We report the first measurement of the double-spin asymmetry A{LT} for charged pion electroproduction in semi-inclusive deep-inelastic electron scattering on a transversely polarized {3}He target. The kinematics focused on the valence quark region, 0.16<x<0.35 with 1.4<Q{2}<2.7  GeV{2}. The corresponding neutron A{LT} asymmetries were extracted from the measured {3}He asymmetries and proton over {3}He cross section ratios using the effective polarization approximation. These new data probe the transverse momentum dependent parton distribution function g{1T}{q} and therefore provide access to quark spin-orbit correlations. Our results indicate a positive azimuthal asymmetry for π{-} production on {3}He and the neutron, while our π{+} asymmetries are consistent with zero.

Pineal parenchymal tumours: minimum apparent diffusion coefficient in prediction of tumour grading

Retrospective assessment was performed of the minimum apparent diffusion coefficient (minADC) together with quantitative assessment of the histopathological features of resected tumour tissue and the Ki-67 labelling index (LI) for predicting pineal parenchymal tumour (PPT) grade. Magnetic resonance images of tumours from 26 male and female patients (mean age 27.7 years) with pathologically confirmed PPTs, comprising 10 pineocytomas (PCs), seven pineal parenchymal tumours of intermediate differentiation (PPTIDs) and nine pineoblastomas (PBs), were reviewed retrospectively. Using ADC maps derived from isotropic diffusion-weighted images, the minADC value of each tumour was determined postoperatively from several regions of interest defined in the tumour, excluding cystic, necrotic, haemorrhagic or calcified components. Surgical intervention was undertaken in all cases. The Ki-67 LI was measured in surgical specimens. Mean minADC and Ki-67 LI showed significant differences among PCs, PPTIDs and PBs, and minADC was negatively correlated with Ki-67 LI. It is concluded that the minADC of PPTs provide useful additional information when predicting tumour grading.

Development and use of EST-SSR markers for assessing genetic diversity in the brown planthopper (Nilaparvata lugens Stål)

To assess genetic diversity in populations of the brown planthopper (Nilaparvata lugens Stål) (Homoptera: Delphacidae), we have developed and applied microsatellite, or simple sequence repeat (SSR), markers from expressed sequence tags (ESTs). We found that the brown planthopper clusters of ESTs were rich in SSRs with unique frequencies and distributions of SSR motifs. Three hundred and fifty-one EST-SSR markers were developed and yielded clear bands from samples of four brown planthopper populations. High cross-species transferability of these markers was detected in the closely related planthopper N. muiri. The newly developed EST-SSR markers provided sufficient resolution to distinguish within and among biotypes. Analyses based on SSR data revealed host resistance-based genetic differentiation among different brown planthopper populations; the genetic diversity of populations feeding on susceptible rice varieties was lower than that of populations feeding on resistant rice varieties. This is the first large-scale development of brown planthopper SSR markers, which will be useful for future molecular genetics and genomics studies of this serious agricultural pest.