A one-step molecular biology method for simple and rapid detection of grass carp Ctenopharyngodon idella reovirus (GCRV) HZ08 strain

Six reverse-transcription loop-mediated isothermal amplification (RT-LAMP) primers designed against conserved regions of segment 6 (s6) gene were used for the detection of grass carp Ctenopharyngodon idella reovirus (GCRV) HZ08 subtype. The entire amplification could be completed within 40 min at 62·3° C. The RT-LAMP showed higher sensitivity than reverse-transcription polymerase chain reaction (RT-PCR). The RNA detection limit was 10 copies µl⁻¹ for RT-LAMP assay and 100 copies µl⁻¹ for conventional RT-PCR. In specificity tests, no cross-reactivity was detected in other viruses from common aquatic animals. In addition, the reaction results can be visualized by using calcein fluorescent dye. Furthermore, a total of 86 samples were tested by RT-LAMP, RT-PCR and virus isolation. The results demonstrated that all 54 specimens identified as positive by virus isolation were also positive when detected by RT-LAMP. Seven out of 54 samples, however, were misidentified by RT-PCR. The RT-LAMP method is more accurate than conventional RT-PCR. The results indicate that RT-LAMP has potential as a simple and rapid diagnosis technique for the detection of GCRV HZ08 subtype infection.

High b-value diffusion tensor imaging of the remote white matter and white matter of obstructive unilateral cerebral arterial regions

AIM

To assess diffusion changes in the remote white matter and areas of white matter with cerebral artery obstruction without magnetic resonance imaging (MRI) evidence of brain parenchymal abnormalities using high b-value diffusion tensor imaging (DTI).

MATERIALS AND METHODS

A total of 34 patients with severe unilateral stenosis (≥75%) or occlusion of the middle cerebral artery (MCA) without abnormal brain parenchymal signals at MRI underwent DTI with a b value of 2200 s/mm(2) at 3 T. Fractional anisotropy (FA), apparent diffusion coefficient (ADC), axial diffusivity (eigenvalue λ₁) and radial diffusivity (eigenvalue λ₂₃) were measured at the bilateral corona radiata, anterior and posterior limbs of the internal capsule, cerebral peduncle, and pons.

RESULTS

The mean FA was significantly lower at the ipsilateral corona radiata and anterior and posterior limbs of the internal capsule than at the contralateral corona radiata and anterior and posterior limbs of the internal capsule (p < 0.05). The mean ADC, λ₁ and λ₂₃ were significantly higher at the ipsilateral corona radiata than at the contralateral corona radiata (p < 0.01). The mean λ₂₃ were significantly higher at the ipsilateral anterior and posterior limb of the internal capsule than at the contralateral anterior and posterior limb of the internal capsule (p < 0.05). The mean ADC, λ₁ and λ₂ ₃were not significantly different between the ipsilateral cerebral peduncle and pons.

CONCLUSIONS

High b-value DTI could sensitively reveal diffusion changes in white matter in regions of cerebral artery obstruction without abnormal anisotropy and diffusivity of the remote white matter of patients with severe MCA stenosis or occlusion without MRI evidence of brain parenchymal abnormalities.

Double prospectively ECG-triggered high-pitch spiral acquisition for CT coronary angiography: initial experience

AIM

To evaluate the feasibility of double prospectively electrocardiogram (ECG)-triggered high-pitch spiral acquisition mode (double high-pitch mode) for coronary computed tomography angiography (CTCA).

MATERIALS AND METHODS

One hundred and forty-nine consecutive patients [40 women, 109 men; mean age 58.2 ± 9.2 years; sinus rhythm ≤70 beats/min (bpm) after pre-medication, body weight ≤100 kg] were enrolled for CTCA examinations using a dual-source CT system with 2 × 128 × 0.6 mm collimation, 0.28 s rotation time, and a pitch of 3.4. Double high-pitch mode was prospectively triggered first at 60% and later at 30% of the R-R interval within two cardiac cycles. Image quality was evaluated using a four-point scale (1 = excellent, 4 = non-assessable).

RESULTS

From 2085 coronary artery segments, 86.4% (1802/2085) were rated as having a score of 1, 12.3% (257/2085) as score of 2, 1.2% (26/2085) as score of 3, and none were rated as "non-assessable". The average image quality score was 1.15 ± 0.26 on a per-segment basis. The effective dose was calculated by multiplying the coefficient factor of 0.028 by the dose-length product (DLP); the mean effective dose was 3.5 ± 0.8 mSv (range 1.7-7.6 mSv). The total dosage of contrast medium was 78.7 ± 2.9 ml.

CONCLUSION

Double prospectively ECG-triggered high-pitch spiral acquisition mode provides good image quality with an average effective dose of less than 5 mSv in patients with a heart rate ≤70 bpm.

CT-scan images preprocessing and segmentation to improve bioprosthesis leaflets morphological analysis

The visualization of bioprosthesis leaflet morphology might help to better understand the underlying mechanism of dysfunction in degenerated aortic bioprosthesis. Because today such visualization of bioprosthesis leaflet morphology is intricate to impossible with other imaging techniques, we hypothesized that the processing of multi-detector CT images would allow better visualization of the prosthetic valve leaflets after biological aortic valve replacement. The purpose of our study was to prospectively evaluate patients with a degenerated aortic bioprosthesis, waiting for reoperation, by using 64-slice CT to evaluate prosthetic leaflets morphology. A semi-automatic segmentation of pre-operative tomodensitometric images was conducted, using 2 different implementations of the region growing algorithm. Here we report all segmentation steps (selection of the region of interest, filtering, segmentation). Studied degenerated aortic bioprostheses were represented by two Carpentier-Edwards Supra Annular Valve (porcine leaflets), one Edwards Perimount (pericardial leaflets) and one Medtronic Mosaic (porcine leaflets). Both segmentation methods (Isotropic Region Growing and Stick Region Growing) allowed a semi-automatic segmentation with 3D reconstruction of all bioprosthetic components (stent, leaflets, degeneration/calcifications). Explanted bioprosthesis CT images were also processed and used as reference. Segmentation results were compared by means of quantitative criteria. Semi-automatic segmentation using region growing algorithm seems to provide an interesting approach for the morphological characterization of degenerated aortic bioprostheses. We believe that in the next future CT scan images segmentation may play an important role to better understand the mechanism of dysfunction in failing aortic bioprostheses. Moreover, bioprostheses 3D reconstructions could be integrated into preoperative planning tools to optimize valve-in-valve procedure.

Clinical analysis of prophylactic central neck dissection for papillary thyroid carcinoma

Purpose

The need of prophylactic central neck dissection (PCND) in patients with papillary thyroid carcinoma (PTC) is still controversial. The major restriction of PCND is the potential complications. We undertook a retrospective study to discuss its necessity in PTC patients.

Methods

A total of 188 patients with PTC who underwent total thyroidectomy and PCND were involved. In all of these, central lymph nodes were pathologic examined. Univariate and multivariate analyses were performed based on tumor location and size, etc.

Results

Overall, node metastases were found in 44.1 % (83/188) of patients. Tumor size was the independent positive predictor for lymph node metastasis, while gender, age, tumor multifocality, tumor location, and capsular infiltration were not independent predictors of central lymph node metastases. Postoperative complications happened in 5.3 % (10/188) of patients, which 4.8 % (9/188) had temporary hypocalcemia and 0 % (0/188) had permanent hypocalcemia. Rates of temporary and permanent recurrent laryngeal nerve injury were 0.5 % (1/188) and 0 % (0/188), respectively.

Conclusions

PCND is recommended in all patients with PTC.

ADAR1 is essential for intestinal homeostasis and stem cell maintenance

Adenosine deaminase acting on RNA 1 (ADAR1) is a double-stranded RNA-editing enzyme that converts adenosine (A) to inosine (I), and essential for normal development. In this study, we reported an essential role of ADAR1 in the survival and maintenance of intestinal stem cells and intestinal homoeostasis by suppressing endoplasmic reticulum (ER) stress and interferon (IFN) signaling. ADAR1 was highly expressed in the Lgr5+ cells, and its deletion in adult mice led to a rapid apoptosis and loss of these actively cycling stem cells in the small intestine and colon. ADAR1 deletion resulted in a drastic expansion of progenitors and Paneth cells but a reduction of three other major epithelial lineages. Moreover, loss of ADAR1 induced ER stress and activation of IFN signaling, and altered expression in WNT targets, followed by intestinal inflammation. An ER stress inhibitor partially suppressed crypt apoptosis. Finally, data from cultured intestinal crypts demonstrated that loss of ADAR1 in the epithelial cells is the primary cause of these effects. These results support an essential role of ADAR1 and RNA editing in tissue homeostasis and stem cells.

Fabrication and characterization of fully flattened carbon nanotubes: a new graphene nanoribbon analogue

Graphene nanoribbons (GNR) are one of the most promising candidates for the fabrication of graphene-based nanoelectronic devices such as high mobility field effect transistors (FET). Here, we report a high-yield fabrication of a high quality another type of GNR analogue, fully flattened carbon nanotubes (flattened CNTs), using solution-phase extraction of inner tubes from large-diameter multi-wall CNTs (MWCNTs). Transmission electron microscopy (TEM) observations show that flattened CNTs have width of typically 20 nm and a barbell-like cross section. Measurements of the low-bias conductance of isolated flattened CNTs as a function of gate voltage shows that the flattened CNTs display ambipolar conduction which is different from those of MWCNTs. The estimated gap based on temperature dependence of conductivity measurements of isolated flattened CNTs is 13.7 meV, which is probably caused by the modified electronic structure due to the flattening.

Observation of an energy-dependent difference in elliptic flow between particles and antiparticles in relativistic heavy ion collisions

Elliptic flow (v(2)) values for identified particles at midrapidity in Au + Au collisions, measured by the STAR experiment in the beam energy scan at RHIC at sqrt[s(NN)] = 7.7-62.4 GeV, are presented. A beam-energy-dependent difference of the values of v(2) between particles and corresponding antiparticles was observed. The difference increases with decreasing beam energy and is larger for baryons compared to mesons. This implies that, at lower energies, particles and antiparticles are not consistent with the universal number-of-constituent-quark scaling of v(2) that was observed at sqrt[s(NN)] = 200 GeV.

Genetic analysis of differentiation of T-helper lymphocytes

In the human immune system, T-helper cells are able to differentiate into two lymphocyte subsets: Th1 and Th2. The intracellular signaling pathways of differentiation form a dynamic regulation network by secreting distinctive types of cytokines, while differentiation is regulated by two major gene loci: T-bet and GATA-3. We developed a system dynamics model to simulate the differentiation and re-differentiation process of T-helper cells, based on gene expression levels of T-bet and GATA-3 during differentiation of these cells. We arrived at three ultimate states of the model and came to the conclusion that cell differentiation potential exists as long as the system dynamics is at an unstable equilibrium point; the T-helper cells will no longer have the potential of differentiation when the model reaches a stable equilibrium point. In addition, the time lag caused by expression of transcription factors can lead to oscillations in the secretion of cytokines during differentiation.

Aberrant intrinsic brain activity and cognitive deficit in first-episode treatment-naive patients with schizophrenia

BACKGROUND

Given the important role of the default mode network (DMN) in cognitive function and the well-known neurocognitive deficit in schizophrenia, it is intriguing to examine systematically the relationship between neurocognitive dysfunction and aberrant intrinsic activities, and also functional connectivity, of the DMN in patients with schizophrenia. Method First-episode, treatment-naive patients with schizophrenia (FES) (n = 115) and healthy controls (n = 113) underwent resting-state functional magnetic resonance imaging (fMRI) scans and neurocognitive tests. Intrinsic neural activities evaluated by using the fragment amplitude of low-frequency fluctuations (fALFF) and the resting-state functional connectivity assessed by seed-based correlational analysis were compared between patients and controls. Aberrant intrinsic activities and DMN connectivity in patients were then correlated to neurocognitive performance and clinical symptoms.

RESULTS

Compared to controls, patients with FES showed decreased fALFF in the bilateral medial prefrontal cortex (MPFC) and the orbitofrontal cortex (OFC), and increased fALFF in the bilateral putamen. Increased functional connectivity with the DMN was observed in the left insula and bilateral dorsolateral PFC (DLPFC) in patients with FES. In patients, aberrant fALFF in the bilateral OFC were correlated with cognitive processing speed; fALFF in the left OFC and right putamen were correlated with the clinical factors excited/activation and disorganization; and increased DMN functional connectivity in the left insula was correlated with the clinical factors positive, excited/activation, disorganization and neurocognitive deficit in the domain of sustained attention.

CONCLUSIONS

These associations between neurocognitive dysfunction and aberrant intrinsic activities, and also functional connectivity, of the DMN in patients with schizophrenia may provide important insights into the neural mechanism of the disease.

Association between lncrna PCGEM1 polymorphisms and prostate cancer risk

BACKGROUND

Prostate cancer (PCa) gene expression marker 1 (PCGEM1), a long noncoding RNA, has drawn increasing attention for its important role in PCa. However, the association between genetic variations in the PCGEM1 gene and risk of PCa has not been investigated yet.

METHODS

We investigated the effect of two tagging single-nucleotide polymorphism (tSNPs; rs6434568 and rs16834898) in PCGEM1 gene on PCa risk in the Chinese men. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the association.

RESULTS

We found a significantly decreased risk of PCa for rs6434568 AC and AC/AA genotype (adjusted OR=0.76, 95% CI=0.60-0.97 for AC; adjusted OR=0.76, 95% CI=0.61-0.96 for AC/AA), as well as rs16834898 AC and AC/CC genotype (adjusted OR=0.76, 95% CI=0.59-0.97 for AC; adjusted OR=0.79, 95% CI=0.62-0.99 for AC/CC), compared with the CC and AA genotypes, respectively. When we evaluated these two tSNPs together based on the risk alleles (that is, rs6434568 C and rs16834898 A), we found that the combined genotypes with four risk alleles were associated with an increased risk of PCa compared with those carrying 0-3 risk alleles (1.53, 1.19-1.97), and this increased risk was more pronounced among subjects of≤70 years (1.80, 1.24-2.62), Gleason score≥7 (1.68, 1.28-2.22) and PSA level≥20 (1.64, 1.24-2.18).

CONCLUSIONS

Our results indicated that PCGEM1 polymorphisms may contribute to PCa risk in Chinese men. Additional functional analyses are required to detect the detailed mechanism underlying the observed association.

Dose-dependent pharmacokinetics of bulleyaconitine A in rats

This study was conducted to determine the pharmacokinetic characteristics of bulleyaconitine A (BLA) after oral gavage and intravenous administration of BLA at a single dose of 0.04, 0.12, 0.36 mg/kg (oral) or 0.02 mg/kg (i.v.) in male Sprague-Dawley rats. Plasma concentration profiles were analysed using a non-compartmental pharmacokinetic method. Following i.v. 0.02 mg/kg and oral administration 0.04, 0.12 or 0.36 mg/kg, the geometric mean Cmax values were 19.97, 2.11, 5.11 and 11.47 ng/ml, respectively; the corresponding geometric mean AUC(0-t) values were 10.50, 3.19, 9.59 and 18.10 ng x h/ml, respectively. The median Tmax values were 0.033, 0.167, 0.167 and 0.167 h, respectively. The terminal elimination half-lives (t1/2) were 1.23, 2.48, 1.93 and 2.17h, respectively. The results showed that Cmax and AUC(0-t) increased with increasing doses of BLA. The increase in exposure with increasing dose was lower than expected under conditions of strict proportionality.

Structure and immune expression analysis of hemoglobin genes from the blood clam Tegillarca granosa

Hemoglobin (Hb) is the major protein component of erythrocytes in animals with red blood, although it can serve additional functions beyond the transport of oxygen. The blood clam (Tegillarca granosa) is one of the few mollusks that has Hb, although the structure and function of molluskan Hbs remain unclear. We characterized two unique and highly compartmentalized blood clam hemoglobin genes, Tg-HbIIA and Tg-HbIIB, at the molecular level. The full-length cDNA of Tg-HbIIA was 731 bp with a 450-bp open reading frame encoding 150 amino acids; that of Tg-HbIIB was 698 bp, with a 456-bp open reading frame encoding 152 amino acids. Their intronic regions were amplified by PCR. The two genes showed the typical 2 intron/3 exon organization found in T. granosa. The 3-D structures of the three blood clam Tg-Hbs were predicted using the SWISS-MODEL Protein Modeling Server, and a phylogenetic analysis was conducted to investigate its evolution. As quantified by qRT-PCR, the expression levels of Tg-HbIIA and Tg-HbIIB were significantly upregulated upon challenge by Vibrio parahaemolyticus, lipopolysaccharides, and peptidoglycans. Three Hb isoforms, Tg-HbI, Tg-HbIIA, and Tg-HbIIB, were found. Specific structures and evolutionary features were found in these molluskan Hb genes. Challenge experiments indicated that Tg-Hbs are involved in immune defense responses against bacterial infection and bacterial pathogenic factors. As this is the first functional research on Hb genes in the blood clam, our findings provide new insight into the innate immune defense mechanisms of T. granosa.