Comparative analysis of the phenotypic characteristics of high- and low-virulent strains of Edwardsiella tarda

Edwardsiella tarda is a causative agent of edwardsiellosis in freshwater and marine fish. Extracellular enzymic, haemolytic, hydrophobic and serum resistance activities, haemagglutination, autoagglutination and siderophores of high- and low- virulent E. tarda strains were examined. The results revealed different haemagglutination, autoagglutination, haemolytic, hydrophobic and serum resistance activities in different strains. Analysis of extracellular proteins (ECPs) and outer membrane proteins (OMPs) demonstrated several major, low molecular weight, virulent-strain-specific proteins, which could be virulence-related. Based on the database search with MALDI-TOF MS data, the closest homologies of the three protein bands Ed1, Ed2 and Ed3 were phosphotransferase enzyme family protein, nitrite reductase [NAD(P)H], large subunit and ATP-dependent Lon protease, respectively. A comparison of pathogenicity of purified lipopolysaccharide (LPS) and lipid A from virulent and avirulent strains demonstrated that LPS was one of the virulence factors of the E. tarda isolates, and lipid A was a biologically active determinant of LPS.

Phylogeography and conservation genetics of Lake Qinghai scaleless carp Gymnocypris przewalskii

The objective of this study was to examine the spatial genetic relationships of the Lake Qinghai scaleless carp Gymnocypris przewalskii within the Lake Qinghai system, determining whether genetic evidence supports the current taxonomy of Gymnocypris przewalskii przewalskii and Gymnocypris przewalskii ganzihonensis and whether Gymnocypris przewalskii przewalskii are returning to their natal rivers to spawn. Comparison of mitochondrial (control region) variation (42 haplotypes in 203 fish) of G. przewalskii with the postulated ancestral species found in the Yellow River, Gymnocypris eckloni (10 haplotypes in 23 fish), indicated no haplotype sharing, but incomplete lineage sorting. Consistent with the sub-species status, an AMOVA indicated that the Ganzi River population was significantly different from all other river populations (F(ST) = 0·1671, P < 0·001). No genetic structure was found among the other rivers in the Lake Qinghai catchment. An AMOVA of amplified fragment length polymorphism (AFLP) loci, however, revealed significant genetic differences between most spawning populations (F(ST) = 0·0721, P < 0·001). Both mitochondrial and AFLP data found significant differences among G. p. przewalskii, G. p. ganzihonensis and G. eckloni (F(ST) values of 0·1959 and 0·1431, respectively, P < 0·001). Consistent with the incomplete lineage sorting, Structure analysis of AFLP loci showed evidence of five clusters. One cluster is shared among all sample locations, one is unique to G. p. ganzihonensis and G. eckloni, and the others are mostly found in G. p. przewalskii. Genetic evidence therefore supports the current taxonomy, including the sub-species status of G. p. ganzihonensis, and is consistent with natal homing of most Lake Qinghai populations. These findings have significant implications for the conservation and management of this unique and threatened species. The evidence suggests that G. p. przewalskii should be treated as a single population for conservation purposes. Exchangeability of the populations, however, should not be used to promote homogenization of fish spawning in the different rivers. As some degree of genetic divergence was detected in this study, it is recommended that the spawning groups be treated as separate management units.

Optofluidic microcavities: Dye-lasers and biosensors

Optofluidic microcavities are integrated elements of microfluidics that can be explored for a large variety of applications. In this review, we first introduce the physics basis of optical microcavities and microflow control. Then, we describe four types of optofluidic dye lasers developed so far based on both simple and advanced device fabrication technologies. To illustrate the application potential of such devices, we present two types of laser intracavity measurements for chemical solution and single cell analyses. In addition, the possibility of single molecule detection is discussed. All these recent achievements demonstrated the great importance of the topics in biology and several other disciplines.

Changes of Serum Brain-Derived Neurotrophic Factor in Children with Obstructive Sleep Apnoea–Hypopnoea Syndrome following Adenotonsillectomy

Children with obstructive sleep apnoea syndrome (OSAS) have substantial cognitive functional morbidity. Brain-derived neurotrophic factor (BDNF) is a key mediator of memory and cognition, but its regulation in OSAS is unknown. Circulating BDNF, transforming growth factor-β1 and 5-hydroxytryptamine levels, cognitive ability and overnight polysomnography were evaluated in 44 children with newly-diagnosed OSAS and in 26 healthy children. All parameters were monitored pre-operatively and at 3, 6 and 12 months after adenotonsillectomy. Pre-operative cognitive ability and sleep parameters were significantly poorer in children with OSAS compared with controls, but BDNF levels were similar. At 3 months post-operation, serum BDNF concentrations decreased, but cognitive ability and sleep parameters remained deficient. At 6 months post-operation, serum BDNF levels, sleep parameters and cognitive ability had improved and, by 12 months, there were no differences between the two groups. It is concluded that adenotonsillectomy can rapidly normalize sleep parameters and improve the cognitive ability of children with OSAS, by regulating the circulating level of BDNF.

Genome-wide association identifies SKIV2L and MYRIP as protective factors for age-related macular degeneration

Age-related macular degeneration (AMD) is the leading cause of blindness in the elderly in the developed world. We conducted a genome-wide association study in a series of families enriched for AMD and completed a meta-analysis of this new data with results from reanalysis of an existing study of a late-stage case-control cohort. We tested the top findings for replication in 1896 cases and 1866 controls and identified two novel genetic protective factors for AMD. In addition to the complement factor H (CFH) (P=2.3 × 10⁻⁶⁴) and age-related maculopathy susceptibility 2 (ARMS2) (P=1.2 × 10⁻⁶⁰) loci, we observed a protective effect at rs429608, an intronic SNP in SKIV2L (P=5.3 × 10⁻¹⁵), a gene near the complement component 2 (C2)/complement factor B (BF) locus, that indicates the protective effect may be mediated by variants other than the C2/BF variants previously studied. Haplotype analysis at this locus identified three protective haplotypes defined by the rs429608 protective allele. We also identified a new potentially protective effect at rs2679798 in MYRIP (P=2.9 × 10⁻⁴), a gene involved in retinal pigment epithelium melanosome trafficking. Interestingly, MYRIP was initially identified in the family-based scan and was confirmed in the case-control set. From these efforts, we report the identification of two novel protective factors for AMD and confirm the previously known associations at CFH, ARMS2 and C3.

Evaluation of SNPs in the chicken HMGA2 gene as markers for body weight gain

A QTL affecting body weight in chickens has been mapped to GGA1, between the markers GCT0006 and MCW0106. The gene HMGA2, which was previously identified as a candidate gene for determining body height in humans and mice, is also conspicuously close to the MCW0106 marker in chickens. Subsequently, 14 SNP markers of HMGA2 were genotyped in CAU chicken resource populations, and the associations between body weight and those SNP markers that displayed polymorphisms were analysed. Three SNPs (rs13849241, rs15231472 and rs13849381) were found to be significantly correlated with body weight in chickens (P < 0.05). Furthermore, haplotypes constructed based on these three SNPs were also discovered to be associated with body weight in chickens at the ages of 6, 7, 9 and 12 weeks. These results suggest that the chicken HMGA2 gene is indeed involved in body weight gain.

Characteristics of prevalence in peripheral arterial disease and correlative risk factors and comorbidities among female natural population in China

BACKGROUND

To investigate the prevalence of peripheral arterial disease (PAD) and correlating risk factors and comorbidities in a natural female population in China, and to study the characteristics of atherosclerotic disease in females.

PATIENTS AND METHODS

Natural population from communities in several cities and districts including Beijing, Shanghai, Changsha, Guangdong, Inner Mongolia, and Xinjiang in China were investigated as study subjects through cluster multistage and random sampling. Ankle-brachial index (ABI) was measured among participants in the communities by trained investigators and correlative information and clinical data were collected. PAD was defined as an ABI≤0.9 in either leg.

RESULTS

21,152 eligible participants were included in the survey. The prevalence in males and females was 2.52 % and 3.66 %, the standardized prevalence was 1.84% and 4.31% respectively, and the prevalence in females was higher than that in males (p<0.01). The prevalence in females obviously increased (p<0.01) with increasing age. More female participants with PAD were over 69 years old compared with those without PAD (18.8% vs. 10.0%, p=0.000) and more frequently have a smoking habit (11.1% vs. 2.5%, p=0.000), lipid disorders (34.8% vs. 29.2%, p=0.047), diabetes mellitus (14.8% vs. 8.6%, p=0.000), coronary heart disease (16.9% vs. 10.0%, p=0.000) and a history of stroke (6.8% vs. 2.3%, p=0.000). Using multiple logistic regression analysis, older age (>69 years old, OR: 1.60, 95% CI: 1.11-2.29), a smoking habit (OR: 5.98, 95% CI: 3.88-9.21), comorbidities of lipid disorders (OR: 1.45, 95% CI: 1.10-1.91), diabetes mellitus (OR: 1.46, 95% CI: 1.02-2.11), coronary heart disease (OR: 1.50, 95% CI: 1.02-2.19)and a history of stroke (OR: 1.71, 95% CI: 1.01-2.91) were correlated with the prevalence of PAD in females in China. Only 0.8% of female patients with PAD had been diagnosed previously.

CONCLUSIONS

The data suggest that the prevalence of PAD in a female natural population in China is higher than that in males. Many conventional risk factors and comorbidities were correlated with the high prevalence of PAD in females. But only very few female patients with PAD were diagnosed. Thus, more measures should be taken to diagnose, prevent and control PAD in females in China.

Persistent spatial working memory deficits in rats following in utero RNAi of Dyx1c1

Disruptions in the development of the neocortex are associated with cognitive deficits in humans and other mammals. Several genes contribute to neocortical development, and research into the behavioral phenotype associated with specific gene manipulations is advancing rapidly. Findings include evidence that variants in the human gene DYX1C1 may be associated with an increased risk of developmental dyslexia. Concurrent research has shown that the rat homolog for this gene modulates critical parameters of early cortical development, including neuronal migration. Moreover, recent studies have shown auditory processing and spatial learning deficits in rats following in utero transfection of an RNA interference (RNAi) vector of the rat homolog Dyx1c1 gene. The current study examined the effects of in utero RNAi of Dyx1c1 on working memory performance in Sprague-Dawley rats. This task was chosen based on the evidence of short-term memory deficits in dyslexic populations, as well as more recent evidence of an association between memory deficits and DYX1C1 anomalies in humans. Working memory performance was assessed using a novel match-to-place radial water maze task that allows the evaluation of memory for a single brief (∼4-10 seconds) swim to a new goal location each day. A 10-min retention interval was used, followed by a test trial. Histology revealed migrational abnormalities and laminar disruption in Dyx1c1 RNAi-treated rats. Dyx1c1 RNAi-treated rats exhibited a subtle, but significant and persistent impairment in working memory as compared to Shams. These results provide further support for the role of Dyx1c1 in neuronal migration and working memory.

Calpain activation through galectin-3 inhibition sensitizes prostate cancer cells to cisplatin treatment

Prostate cancer will develop chemoresistance following a period of chemotherapy. This is due, in part, to the acquisition of antiapoptotic properties by the cancer cells and, therefore, development of novel strategies for treatment is of critical need. Here, we attempt to clarify the role of the antiapoptotic molecule galectin-3 in prostate cancer cells using siRNA and antagonist approaches. The data showed that Gal-3 inhibition by siRNA or its antagonist GCS-100/modified citrus pectin (MCP) increased cisplatin-induced apoptosis of PC3 cells. Recent studies have indicated that cisplatin-induced apoptosis may be mediated by calpain, a calcium-dependent protease, as its activation leads to cleavage of androgen receptor into an androgen-independent isoform in prostate cancer cells. Thus, we examined whether calpain activation is associated with the Gal-3 function of regulating apoptosis. Here, we report that Gal-3 inhibition by siRNA or GCS-100/MCP enhances calpain activation, whereas Gal-3 overexpression inhibits it. Inhibition of calpain using its inhibitor and/or siRNA attenuated the proapoptotic effect of Gal-3 inhibition, suggesting that calpain activation may be a novel mechanism for the proapoptotic effect of Gal-3 inhibition. Thus, a paradigm shift for treating prostate cancer is suggested whereby a combination of a non-toxic anti-Gal-3 drug together with a toxic chemotherapeutic agent could serve as a novel therapeutic modality for chemoresistant prostate cancers.

Measurement of the bottom quark contribution to nonphotonic electron production in p + p collisions at √s=200 GeV

The contribution of B meson decays to nonphotonic electrons, which are mainly produced by the semileptonic decays of heavy-flavor mesons, in p + p collisions at √s=200  GeV has been measured using azimuthal correlations between nonphotonic electrons and hadrons. The extracted B decay contribution is approximately 50% at a transverse momentum of pT≥5  GeV/c. These measurements constrain the nuclear modification factor for electrons from B and D meson decays. The result indicates that B meson production in heavy ion collisions is also suppressed at high pT.

Energetic electrons associated with magnetic reconnection in the magnetic cloud boundary layer

Here is reported in situ observation of energetic electrons (∼100-500 keV) associated with magnetic reconnection in the solar wind by the ACE and Wind spacecraft. The properties of this magnetic cloud driving reconnection and the associated energetic electron acceleration problem are discussed. Further analyses indicate that the electric field acceleration and Fermi-type mechanism are two fundamental elements in the electron acceleration processes and the trapping effect of the specific magnetic field configuration maintains the acceleration status that increases the totally gained energy.

Do children and their parents eat a similar diet? Resemblance in child and parental dietary intake: systematic review and meta-analysis

OBJECTIVES

Parents are believed to have a strong influence on children's eating behaviours. However, previous findings on child-parent resemblance in dietary intakes are mixed. We systematically reviewed and meta-analysed the association (correlations) based on published studies.

METHODS

We searched related studies published since 1980 and found 24 studies meeting inclusion criteria for review and 15 for meta-regression analysis. We compared the associations between parent-child pairs, nutrients, over time and by dietary assessment method.

RESULTS

Most studies were based on small samples. Overall, they suggest a moderate or weak association, but findings varied remarkably. Our meta-analysis showed that average Fisher's transformed correlations were 0.20 (95% CI 0.13 to 0.28) for fat (% energy); for energy, 0.21 (0.18 to 0.24). The correlations varied by parent-child pairs, dietary assessment and countries. Food frequency questionnaires or mixed approaches yielded lower correlation than 24-h recalls or food records. Child self-reported intakes showed weaker correlation and better methodology quality showed stronger correlation in fat intake (% energy), which also became weaker over time.

CONCLUSIONS

Overall, the resemblance is weak, and it varied considerably across studies, nutrients, foods and parent-child pairs.

Dynamic knee loading is related to cartilage defects and tibial plateau bone area in medial knee osteoarthritis

OBJECTIVE

To evaluate the relationship between dynamic mechanical loading, as indicated by external knee adduction moment (KAM) measures during walking, and measures of articular cartilage morphology and subchondral bone size in people with medial knee osteoarthritis (OA).

DESIGN

180 individuals with radiographic medial tibiofemoral OA participated. Peak KAM and KAM angular impulse were measured by walking gait analysis. Tibial cartilage volume and plateau bone area, and tibiofemoral cartilage defects were determined from magnetic resonance imaging using validated methods.

RESULTS

Both peak KAM (coefficient=0.42, 95% confidence interval (CI) 0.04-0.79, P=0.03) and KAM impulse (coefficient=1.79, 95% CI 0.80-2.78, P<0.001) were positively associated with the severity of medial tibiofemoral cartilage defects. KAM impulse was also associated with the prevalence of medial tibiofemoral cartilage defects (odds ratio 4.78, 95% CI 1.10-20.76, P=0.04). Peak KAM (B=0.05, 95% CI 0.01-0.09, P=0.02) and KAM impulse (B=0.16, 95% CI 0.06-0.25, P=0.002) were positively associated with medial:lateral tibial plateau bone area, and KAM impulse was also associated with medial tibial plateau bone area (B=133.7, 95% CI 4.0-263.3, P=0.04). There was no significant association between KAM measures and tibial cartilage volume.

CONCLUSION

Peak KAM and KAM impulse are associated with cartilage defects and subchondral bone area in patients with medial knee OA, suggesting that increased mechanical loading may play a role in the pathological changes in articular cartilage and subchondral bone that occur with medial knee OA.

Comparative serum proteomic analysis of patients with acute-on-chronic liver failure: alpha-1-acid glycoprotein maybe a candidate marker for prognosis of hepatitis B virus infection

The acute-on-chronic liver failure (AoCLF) caused by hepatitis B virus (HBV) infection remains to be a challenge in clinics with a high mortality rate in China, and it is important to identify biomarkers to foresee the prognosis of patients with HBV. The current study analysed serum proteome changes of acute-on-chronic liver failure as a result of acute exacerbation of chronic hepatitis B infection. Serum samples were collected from normal subjects (NS, n = 8), patients with chronic hepatitis B (CHB, n = 12) and patients with AoCLF (n = 12). After removal of albumin/IgG and ultramembrane centrifugation, serum proteins were separated by two-dimensional gel electrophoresis. Differentially expressed spots were identified by matrix-associated laser desorption ionization time-of-flight tandem mass spectrometry. Through the removal of albumin/IgG and ultramembrane centrifugation, the well-resolved and reproducible two-dimensional gel electrophoresis (2-DE) profiles were obtained. A total of 23 proteins were identified on 2-DE profiles by their differential expression between the three cohorts. Mass spectrometry analysis resulted in the identification of 12 proteins unambiguously. Western blot analysis confirmed the proteomics results that the α1-acid glycoprotein (α1-AGP) levels decrease significantly in plasma of patients with AoCLF, but somewhat decreased in patients with chronic HBV. Further α1-AGP levels in bulk serum samples were measured by immune turbidimetry including normal subjects group (n = 25), acute hepatitis group (n = 36), chronic hepatitis group (n = 52) and AoCLF group (n = 48), the level of α1-AGP in AoCLF groups sharply decrease than other groups. Our study shows that α1-AGP may be a potential plasma biomarker for AoCLF diagnosis because of acute exacerbation of chronic hepatitis B infection.

Protective Effect of Resin Coating on the Microleakage of Class V Restorations Following Treatment with Carbamide Peroxide In Vitro

Carbamide peroxide treatment increased the microleakage of Class V conventional glass-ionomer cement and resin modified glass-ionomer cement restorations. The resin coating is an effective method to avoid bleaching-induced microleakage without affecting the bleaching outcome.