Heisenberg-limited atom clocks based on entangled qubits

We present a quantum-enhanced atomic clock protocol based on groups of sequentially larger Greenberger-Horne-Zeilinger (GHZ) states that achieves the best clock stability allowed by quantum theory up to a logarithmic correction. Importantly the protocol is designed to work under realistic conditions where the drift of the phase of the laser interrogating the atoms is the main source of decoherence. The simultaneous interrogation of the laser phase with a cascade of GHZ states realizes an incoherent version of the phase estimation algorithm that enables Heisenberg-limited operation while extending the coherent interrogation time beyond the laser noise limit. We compare and merge the new protocol with existing state of the art interrogation schemes, and identify the precise conditions under which entanglement provides an advantage for clock stabilization: it allows a significant gain in the stability for short averaging time.

Serological and virological surveillance of avian influenza A virus H9N2 subtype in humans and poultry in Shanghai, China, between 2008 and 2010

We report the serological evidence of low-pathogenic avian influenza (LPAI) H9N2 infection in an occupational poultry-exposed population and a general population. A serological survey of an occupational poultry-exposed population and a general population was conducted using a haemagglutinin-inhibiting (HI) assay in Shanghai, China, from January 2008 to December 2010. Evidence of higher anti-H9 antibodies was found in serum samples collected from poultry workers. During this period, 239 H9N2 avian influenza viruses (AIVs) were isolated from 9297 tracheal and cloacal paired specimens collected from the poultry in live poultry markets. In addition, a total of 733 influenza viruses were isolated from 1569 nasal and throat swabs collected from patients with influenza-like symptoms in a sentinel hospital, which include H3N2, H1N1, pandemic H1N1 and B, but no H9N2 virus was detected. These findings highlight the need for long-term surveillance of avian influenza viruses in occupational poultry-exposed workers.

Hepatitis B prophylaxis using lamivudine and individualized low-dose hepatitis B immunoglobulin in living donor liver transplantation

BACKGROUND

Currently, most available experience concerning prophylaxis against hepatitis B virus (HBV) recurrence after living donor liver transplantation (LDLT) is limited to studies of small size and short follow-up. The objective of this study was to evaluate the efficacy of a prophylactic regimen using lamivudine and individualized low-dose intramuscular hepatitis B immunoglobulin (HBIG) in LDLT.

METHODS

We used a database of adult-to-adult right-lobe LDLT procedures performed from June 2002 to April 2012 at our center for HBV-related end-stage liver diseases. Patients were divided into 3 groups: group A, HBV-related decompensated liver cirrhosis; group B, fulminant hepatitis B; and group C, hepatocellular carcinoma (HCC).

RESULTS

During a mean follow-up of 38.3 ± 28.9 months, 8 of 165 (4.8%) recipients developed HBV recurrences. The mean time for HBV reinfection was 15.8 + 11.0 months after transplantation. The overall 1-, 3-, and 5-year HBV recurrence rates were 3%, 7%, and 8.2%, respectively. Both patients with fulminant hepatitis B or HCC seemed to have higher rates of HBV recurrence than those with decompensated liver cirrhosis, albeit not significantly. The independent predictor of HBV recurrence was high HBV DNA level (≥10(5) copies/mL) at LDLT.

CONCLUSIONS

Lamivudine and individualized low-dose intramuscular HBIG provides effective prophylaxis against HBV recurrence after LDLT. Pre-LDLT HBV DNA of ≥ 10(5) copies/mL was associated with HBV recurrence.

Lactobacillus salivarius Ren prevent the early colorectal carcinogenesis in 1, 2-dimethylhydrazine-induced rat model

AIMS

The objective of this study was to investigate the impact of Lactobacillus salivarius Ren (LS) on modulating colonic micro flora structure and influencing host colonic health in a rat model with colorectal precancerous lesions.

METHODS AND RESULTS

Male F344 rats were injected with 1, 2-dimethylhydrazine (DMH) and treated with LS of two doses (5 × 10(8) and 1 × 10(10) CFU kg(-1) body weight) for 15 weeks. The colonic microflora profiles, luminal metabolites, epithelial proliferation and precancerous lesions [aberrant crypt foci (ACF)] were determined. A distinct segregation of colonic microflora structures was observed in LS-treated group. The abundance of one Prevotella-related strain was increased, and the abundance of one Bacillus-related strain was decreased by LS treatment. These changes were accompanied by increased short-chain fatty acid levels and decreased azoreductase activity. LS treatment also reduced the number of ACF by c. 40% and suppressed epithelial proliferation.

CONCLUSIONS

Lactobacillus salivarius Ren improved the colonic microflora structures and the luminal metabolisms in addition preventing the early colorectal carcinogenesis in DMH-induced rat model.

SIGNIFICANCE AND IMPACT OF THE STUDY

Colonic microflora is an important factor in colorectal carcinogenesis. Modulating the structural shifts of microflora may provide a novel option for preventing colorectal carcinogenesis. This study suggested a potential probiotic-based approach to modulate the intestinal microflora in the prevention of colorectal carcinogenesis.

Flame-enhanced laser-induced breakdown spectroscopy

Flame-enhanced laser-induced breakdown spectroscopy (LIBS) was investigated to improve the sensitivity of LIBS. It was realized by generating laser-induced plasmas in the blue outer envelope of a neutral oxy-acetylene flame. Fast imaging and temporally resolved spectroscopy of the plasmas were carried out. Enhanced intensity of up to 4 times and narrowed full width at half maximum (FWHM) down to 60% for emission lines were observed. Electron temperatures and densities were calculated to investigate the flame effects on plasma evolution. These calculated electron temperatures and densities showed that high-temperature and low-density plasmas were achieved before 4 µs in the flame environment, which has the potential to improve LIBS sensitivity and spectral resolution.

Over-expression of LGR5 correlates with poor survival of colon cancer in mice as well as in patients

Leucine-rich repeat-containing G protein-coupled receptor 5(LGR5) was identified as the stem cell marker of colon cancer stem cells(CSCs),which were considered as the main criminal cells initiation and reinitiation of colon cancer. We intended to demonstrate and further explain the relationship between LGR5 and colon cancer in mice model and patients. In our research, we used transcriptional methods and immunohistochemistry to investigate the LGR5 gene and protein expression, examined proliferating cell nuclear antigen(PCNA) and Ki67 which were the classic markers for cell proliferation in LGR5 protein positive and negative colon cancer among mice model and patients. Our results showed that LGR5 mRNA and protein expression was significantly over-expressed in 193/366 patients and 24/40mice model with primary colon cancer contrasted with matched normal tissues; significantly higher LGR5 gene expression was detected in pT4 cases than that in pT3 cases; PCNA and Ki67 expression was much more increase in colon cancer cells with positive LGR5 expression than those with negative LGR5 expression;LGR5 positive cancer not only in mice model but also in patients have shorter survival rate compared with LGR5 negative cancer. All our study manifested that LGR5 took on an important effect in the initiation and progression of colon cancer, provided also more helpful evidence for clinical diagnosis and an useful indicator for adjuvant therapy.

Systematic review and meta-analysis of the effectiveness and safety of extended lymphadenectomy in patients with resectable gastric cancer

Background

The extent of lymphadenectomy in the treatment of gastric cancer has been debated for more than two decades. This meta-analysis sought to evaluate the effectiveness and safety of extended lymphadenectomy in patients with gastric cancer.

Methods

A comprehensive search was performed to identify randomized clinical trials (RCTs) comparing the outcomes of D1 and D2 dissection for gastric cancer in PubMed, EMBASE, the Cochrane Library, Science Citation Index, Web of Science and the Chinese Biomedical Literature Database in any language from inception of the database to March 2012. Meta-analyses were performed using Review Manager software.

Results

Eight RCTs including a total of 2044 patients (D1, 1042; D2, 1002) were eligible for meta-analysis. Five-year survival and haemorrhage rates were similar in the two groups. There were significant differences in morbidity, anastomotic leakage, pancreatic leakage, reoperation rates, wound infection, pulmonary complications and postoperative mortality, all of which favoured D1 dissection. Subgroup analysis indicated a trend towards lower gastric cancer-related mortality in patients undergoing D2 dissection who did not also have resection of the spleen or pancreas.

Conclusion

D2 dissection was associated with a significantly higher postoperative risk. A trend towards lower gastric cancer-related mortality was found following D2 dissection that did not include resection of the spleen or pancreas, but further long-term survival data are needed to determine whether there is a specific survival benefit after D2 dissection.

ZIP4 is a novel diagnostic and prognostic marker in human pancreatic cancer: a systemic comparison between EUS-FNA and surgical specimens

Aberrant expression of a zinc transporter ZIP4 in pancreatic ductal adenocarcinoma (PDAC) has been shown to contribute to tumor progression and is a potential target for individualized therapy. The overall objective of this study was to determine whether ZIP4 could serve as a novel diagnostic and prognostic marker in human PDAC, and if it can be assessed by minimally invasive sampling using endoscopic ultrasound guided fine needle aspiration (EUS-FNA). Immunohistochemistry was performed to compare ZIP4 expression in the PDAC samples obtained from EUS-FNA and matched surgical tumors (parallel control). Samples were reported by sensitivity, specificity, and predictive values, all with 95% confidence intervals (CI). A total of 23 cases with both FNA and surgical specimens were evaluated. We found that ZIP4 was significantly overexpressed in tumor cells from both sets of samples. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of ZIP4 for the diagnosis of PDAC were 72.9%, 72.5%, 76.1%, and 69.0% in EUS-FNA samples, and were 97.9%, 65.4%, 83.9%, and 94.4% in surgical specimens, respectively. The association between the positive rate of ZIP4 expression in FNA and surgical samples is statistically significant (P=0.0216). Both the intensity and percentage of ZIP4 positive cells from the surgical samples correlated significantly with tumor stage (P=0.0025 and P=0.0002). ZIP4 intensity level in FNA samples was significantly associated with tumor differentiation and patient survival. These results indicate that EUS-FNA is capable of non-operative detection of ZIP4, thus offering the potential to direct pre-operative detection and targeted therapy of PDAC.

A microfluidic model for organ-specific extravasation of circulating tumor cells

Circulating tumor cells (CTCs) are the principal vehicle for the spread of non-hematologic cancer disease from a primary tumor, involving extravasation of CTCs across blood vessel walls, to form secondary tumors in remote organs. Herein, a polydimethylsiloxane-based microfluidic system is developed and characterized for in vitro systematic studies of organ-specific extravasation of CTCs. The system recapitulates the two major aspects of the in vivo extravasation microenvironment: local signaling chemokine gradients in a vessel with an endothelial monolayer. The parameters controlling the locally stable chemokine gradients, flow rate, and initial chemokine concentration are investigated experimentally and numerically. The microchannel surface treatment effect on the confluency and adhesion of the endothelial monolayer under applied shear flow has also been characterized experimentally. Further, the conditions for driving a suspension of CTCs through the microfluidic system are discussed while simultaneously maintaining both the local chemokine gradients and the confluent endothelial monolayer. Finally, the microfluidic system is utilized to demonstrate extravasation of MDA-MB-231 cancer cells in the presence of CXCL12 chemokine gradients. Consistent with the hypothesis of organ-specific extravasation, control experiments are presented to substantiate the observation that the MDA-MB-231 cell migration is attributed to chemotaxis rather than a random process.

Contrast enhancement using silica microspheres in coherent anti-Stokes Raman spectroscopic imaging

Coherent anti-Stokes Raman scattering (CARS) microscopy is a powerful imaging technique that can provide chemical information of organic and nonorganic materials through vibrational spectroscopy. However, its contrast is not sufficient for monitoring thin film materials. In this study, silica microspheres were employed for enhancing the signal contrast in CARS imaging. One layer of optically transparent silica microspheres was self-assembled onto polymer grating samples to enhance the CARS signals. The highest contrast enhancement factor of 12.5 was achieved using 6.1-μm-diameter microspheres. Finite-difference time-domain method (FDTD) simulation was conducted to simulate the contrast enhancement with silica microspheres of different diameters.

Screening of biomarkers for lung cancer with gene expression profiling data

OBJECTIVES

Lung cancer is one of the most common malignant tumors, but the etiology is not yet clear. Our study aims to deepen the understandings about the mechanisms of lung cancer via screening relevant key genes and functional pathways.

MATERIALS AND METHODS

Microarray data set was collected and differentially expressed genes (DEGs) were selected out. KEGG pathway analysis and Gene Ontology (GO) enrichment analysis were performed for the DEGs. Interaction networks were constructed for the lung cancer-related DEGs with information from Human Protein Reference Database (HRPD) to screen out potential biomarkers.

RESULTS

Functional annotation revealed that cell cycle, DNA replication, immune system, and signal molecules and interactions were significantly over-represented in all the DEGs, suggesting their close involvement in the development of lung cancer. 40 genes with high degree, betweenness and clustering coefficient were identified from the interaction network. 26 out of them are known cancer genes according to the database F-census. Besides, 4 biomarkers were revealed through analyzing their interactions with oncogenes.

CONCLUSIONS

Our study not only advances the understandings about the molecular mechanisms of lung cancer, but also provides several potential biomarkers for clinical use.

White-matter microstructure in previously drug-naive patients with schizophrenia after 6 weeks of treatment

BACKGROUND

It is not clear whether the progressive changes in brain microstructural deficits documented in previous longitudinal magnetic resonance imaging (MRI) studies might be due to the disease process or to other factors such as medication. It is important to explore the longitudinal alterations in white-matter (WM) microstructure in antipsychotic-naive patients with first-episode schizophrenia during the very early phase of treatment when relatively 'free' from chronicity.

METHOD

Thirty-five patients with first-episode schizophrenia and 22 healthy volunteers were recruited. High-resolution diffusion tensor imaging (DTI) was obtained from participants at baseline and after 6 weeks of treatment. A 'difference map' for each individual was calculated from the 6-week follow-up fractional anisotropy (FA) of DTI minus the baseline FA. Differences in Positive and Negative Syndrome Scale (PANSS) scores and Global Assessment of Functioning (GAF) scores between baseline and 6 weeks were also evaluated and expressed as a 6-week/baseline ratio.

RESULTS

Compared to healthy controls, there was a significant decrease in absolute FA of WM around the bilateral anterior cingulate gyrus and the right anterior corona radiata of the frontal lobe in first-episode drug-naive patients with schizophrenia following 6 weeks of treatment. Clinical symptoms improved during this period but the change in FA did not correlate with the changes in clinical symptoms or the dose of antipsychotic medication.

CONCLUSIONS

During the early phase of treatment, there is an acute reduction in WM FA that may be due to the effects of antipsychotic medications. However, it is not possible to entirely exclude the effects of underlying progression of illness.

Parkinson disease loci in the mid-western Amish

Previous evidence has shown that Parkinson disease (PD) has a heritable component, but only a small proportion of the total genetic contribution to PD has been identified. Genetic heterogeneity complicates the verification of proposed PD genes and the identification of new PD susceptibility genes. Our approach to overcome the problem of heterogeneity is to study a population isolate, the mid-western Amish communities of Indiana and Ohio. We performed genome-wide association and linkage analyses on 798 individuals (31 with PD), who are part of a 4,998 member pedigree. Through these analyses, we identified a region on chromosome 5q31.3 that shows evidence of association (p value < 1 × 10(-4)) and linkage (multipoint HLOD = 3.77). We also found further evidence of linkage on chromosomes 6 and 10 (multipoint HLOD 4.02 and 4.35 respectively). These data suggest that locus heterogeneity, even within the Amish, may be more extensive than previously appreciated.

Cross-sections of 45Sc(n, 2n)44m,gSc reaction from the reaction threshold to 20 MeV

Cross sections of 45Sc(n, 2n)44m,g Sc reactions and their isomeric cross section ratios σ m /σ g have been measured at three neutron energies between 13.5 and 14.8 MeV using the activation technique. The pure cross section of the groundstate was then obtained by utilizing the absolute cross section of the metastable state and analysis methods of residual nuclear decay. The monoenergetic neutron beam was produced via the 3H(d, n)4He reaction. The cross sections were also estimated with the TALYS-1.2 nuclear model code using different level density options, at neutron energies varying from the reaction threshold to 20 MeV. Results are also discussed and compared with some corresponding values found in the literature.

Characterization of statin dose response in electronic medical records

Efforts to define the genetic architecture underlying variable statin response have met with limited success, possibly because previous studies were limited to effect based on a single dose. We leveraged electronic medical records (EMRs) to extract potency (ED50) and efficacy (Emax) of statin dose-response curves and tested them for association with 144 preselected variants. Two large biobanks were used to construct dose-response curves for 2,026 and 2,252 subjects on simvastatin and atorvastatin, respectively. Atorvastatin was more efficacious, was more potent, and demonstrated less interindividual variability than simvastatin. A pharmacodynamic variant emerging from randomized trials (PRDM16) was associated with Emax for both. For atorvastatin, Emax was 51.7 mg/dl in subjects homozygous for the minor allele vs. 75.0 mg/dl for those homozygous for the major allele. We also identified several loci associated with ED50. The extraction of rigorously defined traits from EMRs for pharmacogenetic studies represents a promising approach to further understand the genetic factors contributing to drug response.

Early endovascular treatment of superior mesenteric occlusion secondary to thromboemboli

OBJECTIVE

To evaluate our early experience with endovascular revascularization in patients with acute thromboembolic occlusion of the superior mesenteric artery (SMA).

METHODS

A retrospective review was conducted of all patients who underwent endovascular revascularization for acute thromboembolic SMA occlusion from May 2005 to May 2012. Endovascular revascularization was performed using aspiration, intra-arterial thrombolysis, and adjunctive stent-placement techniques. Laparotomy was performed if the patient developed clinical signs of advanced bowel ischemia after endovascular procedure.

RESULTS

Twenty-one patients underwent endovascular revascularization for acute thromboembolic SMA occlusion. All presented with acute-onset abdominal pain. Three patients had rebound tenderness before the procedure. Computed tomography angiography revealed complete occlusion in seven cases and incomplete occlusion in 14 cases, with no evidence of free gas or bowel necrosis. The median duration from onset of symptoms to revascularization was 8.7 ± 4.1 hours (range, 2-18 hours). Completely successful endovascular revascularization occurred in six cases (aspiration alone, 3 cases; combined aspiration and urokinase, 3 cases); partial success was achieved in 15 cases (aspiration alone, 4 cases; combined aspiration and urokinase, 10 cases; and combined aspiration, urokinase, and stent placement, 1 case). Laparotomy was required in five patients, all of whom had SMA main trunk complete occlusion and required small bowel resection. The 30-day mortality for all patients was 9.5%. During a median follow-up of 26 months, 15 patients remained asymptomatic, three patients reported occasional abdominal pain, and one patient had temporary short-bowel syndrome.

CONCLUSIONS

Percutaneous revascularization is a promising alternative to surgery for acute SMA occlusion in selected patients who have no signs of advanced bowel ischemia. Early diagnosis followed by prompt endovascular intervention with close postprocedural monitoring is key. Laparotomy is indicated in patients who develop new or worsening signs of peritonism after endovascular procedure, particularly in those who had complete occlusion of the main trunk of the SMA.

Fronto-parietal white matter microstructural deficits are linked to performance IQ in a first-episode schizophrenia Han Chinese sample

BACKGROUND

Evidence shows that cognitive deficits and white matter (WM) dysconnectivity can independently be associated with clinical manifestations in schizophrenia. It is important to explore this triadic relationship in order to investigate whether the triplet could serve as potential extended endophenotypes of schizophrenia.

METHOD

Diffusion tensor images and clinical performances were evaluated in 122 individuals with first-episode schizophrenia and 122 age- and gender-matched controls. In addition, 65 of 122 of the patient group and 40 of 122 controls were measured using intelligence quotient (IQ) testing.

RESULTS

The schizophrenia group showed lower fractional anisotropy (FA) values than controls in the right cerebral frontal lobar sub-gyral (RFSG) WM. The schizophrenia group also showed a significant positive correlation between FA in the RFSG and performance IQ (PIQ) ; in turn, their PIQ score showed a significant negative correlation with negative syndromes.

CONCLUSIONS

Overall, these findings support the hypothesis that WM deficits may be a core deficit that contributes to cognitive deficits as well as to negative symptoms.