Experimental study of modified Tavis-Cummings model with directly-coupled superconducting artificial atoms

The Tavis-Cummings model is intensively investigated in quantum optics and has important applications in generation of multi-atom entanglement. Here, we employ a superconducting circuit quantum electrodynamic system to study a modified Tavis-Cummings model with directly-coupled atoms. In our device, three superconducting artificial atoms are arranged in a chain with direct coupling through fixed capacitors and strongly coupled to a transmission line resonator. By performing transmission spectrum measurements, we observe different anticrossing structures when one or two qubits are resonantly coupled to the resonator. In the case of the two-qubit Tavis-Cummings model without qubit-qubit interaction, we observe two dips at the resonance point of the anticrossing. The splitting of these dips is determined by Δ λ=2g12+g32, where g1 and g3 are the coupling strengths between Qubit 1 and the resonator, and Qubit 3 and the resonator, respectively. The direct coupling J12 between the two qubits results in three dressed states in the two-qubit Tavis-Cummings model at the frequency resonance point, leading to three dips in the transmission spectrum. In this case, the distance between the two farthest and asymmetrical dips, arising from the energy level splitting, is larger than in the previous case. The frequency interval between these two dips is determined by the difference in eigenvalues (Δ λ=ε 1+-ε 1-), obtained through numerical calculations. What we believe as novel and intriguing experimental results may potentially advance quantum optics experiments, providing valuable insights for future research.

[Analysis of work-related musculoskeletal disorders among automobile manufacturing logistics workers in Guangzhou]

Objective: To investigate the occurrence of work-related musculoskeletal disorders (WMSDs) in logistics workers of automobile manufacturing enterprises in Guangzhou, and explore their potential categories and influencing factors, so as to provide basis for the prevention and control of WMSDs in logistics workers of automobile manufacturing enterprises. Methods: From April to May 2020, a convenient sampling method was adopted to select 1442 logistics workers in 2 automobile manufacturing enterprises in Guangzhou as the research objects. The incidence of WMSDs among them was investigated by using the Nordic Musculoskeletal Disorders Questionnaire, and the incidence pattern of WMSDs among the subjects was analyzed by the method of potential category analysis. Chi-square test and multiple logistic regression model were used to analyze the influencing factors of the disease. Results: The total prevalence of WMSDs was 42.9% (619/1442). The three parts with high prevalence of WMSDs were neck (23.5%, 339/1442), shoulder (21.3%, 307/1442) and lower back (19.1%, 275/1442). 69.0% (427/619) of the patients showed simultaneous disease in two or more sites. The subjects were divided into four latent groups by the analysis of latent categories: the group with multiple body parts (4.51%), the group with very low or no disease (70.39%), the group with shoulder and neck and upper back (11.37%), and the group with limbs and lower back (13.73%). Multivariate logistic regression showed that compared with the "very low or no disease group", the risk factors of multiple body parts of automotive logistics workers suffering from WMSDs mainly included: Working posture uncomfortable (OR=3.10, 95%CI: 1.44~6.70, P=0.004), often bend and turn (OR=2.36, 95%CI: 1.05~5.29, P=0.037), bend your knees homework for a long time (OR=2.29, 95%CI: 1.17~4.47, P=0.015) ; Working posture uncomfortable (OR=2.26, 95%CI: 1.51~3.38, P<0.001), bending the neck (OR=1.68, 95%CI: 1.03~2.74, P=0.036), neck minister time keep the same position (OR=1.81, 95%CI: 1.22~2.67, P= 0.003) It is a risk factor for shoulder, neck and upper back WMSDs; Risk factors for limb-lower back WMSDs include: Length > 10 years (OR=2.16, 95%CI: 1.24~3.78, P<0.001), the working position uncomfortable (OR=2.38, 95%CI: 1.63~3.48, P<0.001), bending the neck (OR=1.66, 95%CI: 1.03~2.68, P=0.039) . Conclusion: The prevalence rate of WMSDs among logistics workers in automobile manufacturing enterprises is high, which has obvious characteristics of classification and comorbis, and is closely related to individual characteristics such as sufficient rest time and working posture of workers.

[Research and reflection on the diversified method system of multi-stages and multi-scenarios surveillance and early warning of infectious diseases]

With the outbreak of infectious diseases, more and more attention has been paid to surveillance and early warning work. Timely and accurate monitoring data is the basis of infectious diseases prevention and control. Effective early warning methods for infectious diseases can improve the timeliness and sensitivity of early warning work. This paper briefly introduces the intelligent early warning model of infectious diseases, summarizes the emerging surveillance and early warning methods of infectious diseases, and seeks the possibility of diversified surveillance and early warning in different epidemic stages and different outbreak scenarios of infectious diseases. This paper puts forward the idea of constructing a diversified method system of infectious diseases surveillance and early warning based on multi-stages and multi-scenarios and discusses the future development trend of infectious diseases surveillance and early warning, in order to provide reference for improving the construction level of infectious diseases surveillance and early warning system in China.

Synergistic effect of double Schottky potential well and oxygen vacancy for enhanced plasmonic photocatalytic U(VI) reduction

Plasmonic photocatalysis is an effective strategy to solve radioactive uranium hazards in wastewater. A plasmonic photocatalyst Bi/Bi₂O_3-x@COFs was synthesized by in-situ growth of covalent organic frameworks (COFs) on Bi/Bi₂O_3-x surface for the U(VI) adsorption and plasmonic photoreduction in rare earth tailings wastewater. The presence of oxygen vacancy in Bi/Bi₂O_3-x and Schottky potential well formed by Bi and Bi₂O_3-x interface increased the number of free electrons, which induced localized surface plasmon resonance (LSPR) and enhanced the light absorption performance of composites. In addition, oxygen vacancy improved the Fermi level of Bi/Bi₂O_3-x, leading to another potential well between Bi₂O_3-x and COFs interface. The electron transport direction was reversed, thus increasing the electron density of COFs layer. COFs was an N-type semiconductor with specific binding U(VI) groups and suitable band structure, which could be used as an active reaction site. Bi/Bi₂O_3-x@COFs had 1411.5 mg g^-1 removal capacity and high separation coefficient for U(VI) due to the synergistic action of photogenerated electrons and hot electrons. Moreover, the removal rate of uranium from rare earth tailings wastewater by regenerated Bi/Bi₂O_3-x@COFs was over 93.9%. The scheme of introducing LSPR and Schottky potential well provides another way to improve the photocatalytic effect.

[Thinking about development of multi-channel surveillance and multi-dimensional early warning system of emerging respiratory communicable diseases]

The world has paid a heavy price for the pandemic of the emerging respiratory communicable disease, so more concern about communicable disease surveillance and early warning has been aroused. This paper briefly reviews the establishment of the surveillance and early warning system of respiratory communicable diseases in China, discusses its future development and introduces the novel surveillance methods and early warning models for the purpose of establishment of a multi-channel surveillance and multi-dimensional early warning system of communicable diseases in the future and the improvement of the prevention and control of emerging respiratory communicable diseases in China.

[The status of projects funded in division of preventive medicine in National Natural Science Foundation of China from the financial year 2007-2021]

It is of great significance to analyze the configuration of programs funded by the National Natural Science Foundation of China using funding data in the field of preventive medicine from 2007 to 2021. The analysis mainly focused on the funding status of the program, funding amount, funded institutions and personnel. A total of 5 349 programs in the discipline of preventive medicine were funded over the last 15 years. The funding amount in this discipline accounted for a relatively low proportion in the total funding amount of the Department of Medical Sciences and this proportion also showed a decreasing trend. Non-infectious disease epidemiology, human nutrition, and health toxicology were the top three subdisciplines of all funded programs in preventive medicine. The proportion of programs led by young scholars was gradually rising over the years, and young scholars were playing an increasingly influential role in scientific research. The funding status among each subdiscipline and institution also varied. The results of this study reflected the thriving of preventive medicine. Meanwhile, some problems and dilemmas were also revealed in its current development. Hopefully, this study could provide valuable information for institutions and preventive medicine researchers to apply for National Natural Science Foundation, and promote the long-term development of preventive medicine in the future.

Efficacy and safety of sirolimus early conversion protocol in liver transplant patients with hepatocellular carcinoma: A single-arm, multicenter, prospective study

Mammalian target of rapamycin (mTOR) inhibitor as an attractive drug target with promising antitumor effects has been widely investigated. High quality clinical trial has been conducted in liver transplant (LT) recipients in Western countries. However, the pertinent studies in Eastern world are paucity. Therefore, we designed a clinical trial to test whether sirolimus can improve recurrence-free survival (RFS) in hepatocellular carcinoma (HCC) patients beyond the Milan criteria after LT. This is an open-labeled, single-arm, prospective, multicenter, and real-world study aiming to evaluate the clinical outcomes of early switch to sirolimus-based regimens in HCC patients after LT. Patients with a histologically proven HCC and beyond the Milan criteria will be enrolled. The initial immunosuppressant regimens are center-specific for the first 4-6 weeks. The following regimens integrated sirolimus into the regimens as a combination therapy with reduced calcineurin inhibitors based on the condition of patients and centers. The study is planned for 4 years in total with a 2-year enrollment period and a 2-year follow-up. We predict that sirolimus conversion regimen will provide survival benefits for patients particular in the key indicator RFS as well as better quality of life. If the trial is conducted successfully, we will have a continued monitoring over a longer follow-up time to estimate indicator of overall survival. We hope that the outcome will provide better evidence for clinical decision-making and revising treatment guidelines based on Chinese population data. Trial register: Trial registered at http://www.chictr.org.cn: ChiCTR2100042869.

[Advance on theoretical epidemiology models research of prevention and control of COVID-19]

COVID-19 has brought a significant impact to the global health system, and also opportunities and challenges to epidemiological researches. Theoretical epidemiological models can simulate the process of epidemic in scenarios under different conditions. Therefore, modeling researches can analyze the epidemical trend of COVID-19, predict epidemical risks, and evaluate effects of different control measures and vaccine policies. Theoretical epidemiological modeling researches provide scientific advice for the prevention and control of infectious diseases, and play a crucial role in containing COVID-19 over the past year. In this study, we review the theoretical epidemiological modeling researches on COVID-19 and summarize the role of theoretical epidemiological models in the prevention and control of COVID-19, in order to provide reference for the combination of mathematical modeling and epidemic control.

[Analysis on dynamical mechanism of multi outbreaks of COVID-19]

Objective: In the context of COVID-19 pandemic, the epidemic severities, non-pharmaceutical intervention intensities, individual behavior patterns and vaccination coverage vary with countries in the world. China has experienced a long period without indigenous cases, unfortunately, multi local outbreaks caused by imported cases and other factors have been reported, posing great challenges to COVID-19 prevention and control in China. Thus it is necessary to explore the mechanisms of the re-emerged COVID-19 epidemics and their differences. Methods: Based on susceptible exposed infectious recovered (SEIR) epidemic dynamics model, we developed a set of novel evolution equations which can describe the dynamic processes of integrated influence of interventions, vaccination coverage and individual behavior changes on the re-emergency of COVID-19 epidemic. We developed methods to calculate the optimal intervention intensity and vaccination rate at which the size of susceptible population can be reduced to less than threshold for the re-emergency of COVID-19 epidemic. Results: If strong interventions or super interventions are lifted too early, even a small cause can lead to the re-emergence of COVID-19 epidemic at different degrees. Moreover, the stronger the early control measures lifted are, the more severe the epidemic is. The individual behavior changes for the susceptibility to the epidemic and the enhancement or lifting of prevention and control measures are key factors to influence the incidence the multi outbreaks of COVID-19. The optimist early intervention measures and timely optimization of vaccination can not only prevent the re-emergency of COVID-19 epidemic, but also effectively lower the peak of the first wave of the epidemic and delay its arrival. Conclusion: The study revealed that factors for the re-emergence of COVID-19 epidemics included the intensity and lifting of interventions, the change of individual behavior to the response of the epidemic, external incentives and the transmissibility of COVID-19.

[Construction of urban scale-free network model and its epidemiological significance in the prevention and control of COVID-19]

COVID-19 is a public health emergency currently. In this study, a scale-free network model is established based on the Spring Migration data in 2020.The cities is clustered into three different modules. The epidemic of the cities in the black module was the most serious, followed by the red and the cyan. The black module contains 9 cities in Zhejiang province and 8 cities in Guangdong province, most of them located in the southeast coastal economic belt. These cities should be the key cities for epidemic prevention and control.

[Progress of research regarding the influenza early warning system, based on "Big Data"]

Shortcomings have been inherited in the traditional influenza early warning system, often expressed through the scope, accuracy on prediction and real-time performance of the monitor related programs. With the new round of scientific and technological revolution and the increasingly maturity of modern information system, related technology on influenza early warning has become the focus of research in this field, based on big data analysis technology. Using the traditional influenza surveillance and early warning system as reference, this paper summarizes the progress of influenza early warning research, based on the Internet, influencing factors, time and space trends, and risk assessment etc., to summarize the trends on the advantages, shortcomings and future development of big data, used in the early warning system on influenza.

[Research progress on the association between HIV antiretroviral therapy and the outbreak]

Since the implementation of antiretroviral therapy (ART), it has achieved remarkable results in the field of HIV/AIDS treatment. However, when the treatment is applied to the population-level, the actual impact of ART on the HIV epidemic becomes a hot topic in the field. This paper will summarize the research on ART and HIV epidemic in recent years, and discuss the impact of ART on the trend of HIV epidemic, so as to provide scientific support and suggestions for the role of treatment is prevention.

Topologically Protected Quantum Coherence in a Superatom

Exploring the properties and applications of topological quantum states is essential to better understand topological matter. Here, we theoretically study a quasi-one-dimensional topological atom array. In the low-energy regime, the atom array is equivalent to a topological superatom. Driving the superatom in a cavity, we study the interaction between light and topological quantum states. We find that the edge states exhibit topology-protected quantum coherence, which can be characterized from the photon transmission. This quantum coherence helps us to find a superradiance-subradiance transition, and we also study its finite-size scaling behavior. The superradiance-subradiance transition also exists in symmetry-breaking systems. More importantly, it is shown that the quantum coherence of the subradiant edge state is robust to random noises, allowing the superatom to work as a topologically protected quantum memory. We suggest a relevant experiment with three-dimensional circuit QED. Our study may have applications in quantum computation and quantum optics based on topological edge states.

Post-transplant infection improves outcome of hepatocellular carcinoma patients after orthotopic liver transplantation

BACKGROUND

Tumor recurrence after orthotopic liver transplantation (OLT) remains a serious threat for long-term survival of the recipients with hepatocellular carcinoma (HCC), since very few factors or measures have shown impact on overcoming HCC recurrence after OLT. Postoperative infection suppresses tumor recurrence and improves patient survival in lung cancer and malignant glioma probably via stimulating the immune system. Post-transplant infection (PTI), a common complication, is deemed to be harmful for the liver transplant recipients from a short-term perspective. Nevertheless, whether PTI inhibits HCC recurrence after OLT and prolongs the long-term survival of HCC patients needs to be clarified.

AIM

To investigate the potential influence of PTI on the survival and tumor recurrence of patients with HCC after OLT.

METHODS

A total of 238 patients with HCC who underwent OLT between August 2002 and July 2016 at our center were retrospectively included and accordingly subdivided into a PTI group (53 patients) and a non-PTI group (185 patients). Univariate analyses, including the differences of overall survival (OS), recurrence-free survival (RFS), and post-recurrence survival (PRS), between the PTI and non-PTI subgroups as well as survival curve analysis were performed by the Kaplan-Meier method, and the differences were compared using the log rank test. The variables with a P-value < 0.1 in univariate analyses were included in the multivariate survival analysis by using a Cox proportional-hazards model.

RESULTS

The 1-, 3-, and 5-year OS and RFS rates of the whole cohort were 86.6%, 69.0%, and 63.6%, and 75.7%, 60.0%, and 57.3%, respectively. The 1-, 3-, and 5-year OS rates for the PTI patient group (96.0%, 89.3%, and 74.0%) were significantly higher than those for the non-PTI group (84.0%, 63.4%, and 60.2%) (P = 0.033). The absence of PTI was an independent risk factor for dismal OS (relative risk [RR] = 2.584, 95%CI: 1.226-5.449) and unfavorable RFS (RR = 2.683, 95%CI: 1.335-5.390). Subgroup analyses revealed that PTI remarkably improved OS (P = 0.003) and RFS (P = 0.003) rates of HCC patients with vascular invasion (IV), but did not impact on OS (P = 0.404) and RFS (P = 0.304) of patients without VI. Among the patients who suffered post-transplant tumor recurrence, patients with PTI showed significantly better OS (P = 0.026) and PRS (P = 0.042) rates than those without PTI.

CONCLUSION

PTI improves OS and RFS of the transplant HCC patients at a high risk for post-transplant death and tumor recurrence, which is attributed to suppressive effect of PTI on HCC recurrence.

High promoter activity of cytokeratin-19 gene in cholangiocarcinoma

Conditionally replicating adenoviral vectors constructed with tumor-specific promoters (TSPs) offers a viable tool for the treatment of cholangiocarcinoma. The aim of the present study was to investigate cholangiocarcinoma-specific TSPs that remain active in adenoviral constructs in gene therapy. The mRNA expressions of cyclooxygenase-2, cytokeratin-19 (CK19), mucin-1, midkine and telomerase reverse transcriptase were determined in human cholangiocarcinoma cell lines, primary human hepatocytes and cholangiocytes using reverse transcription-quantitative polymerase chain reaction. The candidate promoters constructed in adenoviral vectors were analyzed for their activities in cholangiocarcinoma cell lines, primary human hepatocytes and cholangiocytes using dual-luciferase reporter assays. The mRNA expression of CK19 was markedly higher in the QBC939 cell line, indicating specificity to cholangiocarcinoma. Moreover, the promoter activity of CK19 in the adenoviral vector in infected cholangiocarcinoma cells was found to be significantly stronger compared with that in infected primary human hepatocytes and cholangiocytes. CK19 may be implicated in the pathogenesis of cholangiocarcinoma, as demonstrated by the stronger activity of its promoter, as well as the higher expression of mRNA in tumor cells. Therefore, the use of the promoter sequence of the CK19 gene may represent a potential tool in cholangiocarcinoma-specific adenoviral gene therapy.

Clinical and pathologic predictors of central lymph node metastasis in papillary thyroid microcarcinoma: a retrospective cohort study

OBJECTIVE

To identify the clinical and pathological predictors of central lymph node metastasis (CLNM) in patients with clinically lymph node-negative papillary thyroid microcarcinoma (PTMC).

MATERIALS AND METHODS

Data pertaining to 541 clinically lymph node-negative PTMC patients who underwent thyroid surgery at the Shanghai General Hospital between January 2010 and December 2013 were retrospectively analyzed. According to histopathological evidence of central lymph node involvement, patients were divided into central lymph node metastasis (CLNM)-positive and CLNM-negative groups; risk factors for CLNM were identified statistically.

RESULTS

LNM was found in 148 (27.4%) patients. Gender (P = 0.002), age (P < 0.001), tumor size (P < 0.001), multifocality (P < 0.001), and extrathyroidal extension (P < 0.001) were significantly different between CLNM-positive and CLNM-negative groups. On multivariate analyses, male sex (odds ratio [OR] = 2.656), age <45 years (OR = 4.184), tumor size >0.575 cm (OR = 2.105), gross extrathyroidal extension (OR = 14.605) and multifocality (OR = 2.084) were independent risk factors for CLNM. Among patients who did not have any of these five risk factors, only 3.9% were found to have CLNM.

CONCLUSIONS

A relatively high prevalence of CLNM was observed in patients with clinically lymph node-negative PTMC. CLNM was associated with male sex, younger age, larger tumor size, extrathyroidal extension and multifocal PTMC.

Association between donor and recipient Interleukin-18 gene polymorphisms and the risk of infection after liver transplantation

PURPOSE

The purpose of this study was to retrospectively evaluate the association between Interleukin-18 (IL-18) gene polymorphisms of the donor and recipient in liver transplant patients with bacterial infections.

METHODS

Five single nucleotide polymorphisms (SNPs) (rs7106524, rs5744247, rs1946518, rs549908 and rs187238) of the IL-18 gene from the donors were genotyped and their association with post-operative bacterial infections was evaluated in liver transplant patients (N=113). A second independent group of liver transplant patients from a different organ transplant centre was also recruited for validation purposes (N=44).

RESULTS

IL-18 mRNA mean expression levels and protein levels were significantly lower in liver transplant patients with bacterial infections. For the donor SNP rs1946518, more recipients carried the A allele in the bacterial-infected group than the uninfected group (61.4% vs 39.7%; P ≤0.002). The mean IL-18 mRNA expression and protein levels were significantly lower in the transplanted livers of recipients carrying the rs1946518 AA genotype compared with those from recipients with CC genotype (3.64, 3.33 vs. 2.75, P≤0.048). The A allele of rs1946518 also resulted in lower luciferase activity than the C allele in a reporter assay. The area under ROC curve indicated that the rs1946518 SNP genotype in the donor liver predicted an increased risk of bacterial infection after liver transplantation (AUROC>0.82).

CONCLUSIONS

These findings indicate that the IL-18 rs1946518 SNP in the donor liver is a risk factor for developing bacterial infection after liver transplantation.

[HCV infection status and risk factors in remunerated blood donors in Jiangsu province]

OBJECTIVE

To investigate the infection status of HCV in remunerated blood donors and risk factors in Jiangsu province.

METHODS

A Cross-sectional study was conducted among people aged >50 years. Questionnaires were used to collect the information about their demographic characteristics and risk behaviors, and venous blood samples were collected from them to detect HCV anti-body, HCV-RNA and other biochemical indicators. EpiData and Stata were used for data entry and statistical analysis.

RESULTS

The overall HCV sero-prevalence rates were 22.55% and 61.05% among remunerated blood donors. Data from multiple stepwise regression analysis showed that alanine aminotransferase(ALT)(adjusted OR=1.38, 95%CI: 1.18-1.62)and aspartate aminotransferase(AST)(adjusted OR=1.30, 95%CI: 1.10-1.54)were associated with the outcomes of HCV infection, and fasting plasma glucose(adjusted OR=1.17, 95%CI: 1.01-1.35)were associated with HCV RNA viral loads.

CONCLUSION

The prevalence of HCV infection in remunerated blood donors was high, clinical ALT, AST and fasting plasma glucose levels were associated with the risk for HCV infection and HCV RNA viral load.

SERPINA4 is a novel independent prognostic indicator and a potential therapeutic target for colorectal cancer

Serpina family A member 4 (SERPINA4), also known as kallistatin, exerts important effects in inhibiting tumor growth and angiogenesis in many malignancies. However, the precise role of SERPINA4 in CRC has not been fully elucidated. The present study aimed to investigate the expression of SERPINA4 and its clinical significance in CRC. Quantitative real-time polymerase chain reaction (qRT-PCR) and western blot analyses showed that the mRNA and protein expression of SERPINA4 in colorectal cancer (CRC) specimens was significantly decreased than that in adjacent normal mucosa. Immunohistochemistry (IHC) was conducted to characterize the expression pattern of SERPINA4 by using a tissue microarray (TMA) containing 327 archived paraffin-embedded CRC specimens. Statistical analyses revealed that decreased SERPINA4 expression was significantly associated with invasion depth, nodal involvement, distant metastasis, American Joint Committee on Cancer (AJCC) stage, and tumor differentiation. SERPINA4 was also an independent prognostic indicator of disease-free survival and overall survival in patients with CRC. Furthermore, the impact of altered SERPINA4 expression on CRC cells was analyzed with a series of in vitro and in vivo assays. The results demonstrated that SERPINA4 significantly inhibits malignant tumor progression and serves as a novel prognostic indicator and a potential therapeutic target for CRC.

Resolvin D1 protects against inflammation in experimental acute pancreatitis and associated lung injury

Acute pancreatitis is an inflammatory condition that may lead to multisystemic organ failure with considerable mortality. Recently, resolvin D1 (RvD1) as an endogenous anti-inflammatory lipid mediator has been confirmed to protect against many inflammatory diseases. This study was designed to investigate the effects of RvD1 in acute pancreatitis and associated lung injury. Acute pancreatitis varying from mild to severe was induced by cerulein or cerulein combined with LPS, respectively. Mice were pretreated with RvD1 at a dose of 300 ng/mouse 30 min before the first injection of cerulein. Severity of AP was assessed by biochemical markers and histology. Serum cytokines and myeloperoxidase (MPO) levels in pancreas and lung were determined for assessing the extent of inflammatory response. NF-κB activation was determined by Western blotting. The injection of cerulein or cerulein combined with LPS resulted in local injury in the pancreas and corresponding systemic inflammatory changes with pronounced severity in the cerulein and LPS group. Pretreated RvD1 significantly reduced the degree of amylase, lipase, TNF-α, and IL-6 serum levels; the MPO activities in the pancreas and the lungs; the pancreatic NF-κB activation; and the severity of pancreatic injury and associated lung injury, especially in the severe acute pancreatitis model. These results suggest that RvD1 is capable of improving injury of pancreas and lung and exerting anti-inflammatory effects through the inhibition of NF-κB activation in experimental acute pancreatitis, with more notable protective effect in severe acute pancreatitis. These findings indicate that RvD1 may constitute a novel therapeutic strategy in the management of severe acute pancreatitis.

Long-Term Outcomes of Simultaneous Liver-Kidney Transplant Patients with Hepatitis B Compared to with Liver Transplant Alone

BACKGROUND

The number and survival rate of simultaneous liver-kidney transplant (SLKT) recipients have increased dramatically since 2002. However, the long-term effectiveness of SLKT in patients with hepatitis B is unknown.

MATERIAL/METHODS

Forty-six patients who visited the Organ Transplant Center of the Shanghai First People's Hospital between January 2001 and May 2005 had hepatitis B virus infection and renal failure (any degree), and underwent organ transplantation: 21 patients underwent SLKT and 25 patients underwent liver transplant (LT) alone.

RESULTS

The 1-, 3-, and 5-year survival rates of SLKT recipients were 90.5%, 81.0%, and 81.0%, respectively. Incidence of acute hepatic allograft rejection between SLKT recipients and LT recipients (33% vs. 16%) did not reach significance (P=0.170). Despite higher infection rate, more prevalent hepatitis B relapse, and longer stay in the intensive care unit, SLKT recipients experienced significantly higher 1-year survival rate (90.5%) compared with LT recipients (60%, P=0.019). Multivariate regression analysis revealed that postoperative renal failure (odds ratio (OR)=48, P=0.003) and Risk/Injury/Failure/Loss/End-stage (RIFLE) stage (OR=8, P=0.012) were independent risk factors for postoperative death after LT.

CONCLUSIONS

SLKT in patients with hepatitis B had higher early-stage infection rate, but had a higher long-term survival rate compared with the LT group. Although the incidence of postoperative hepatitis B relapse in SLKT recipients was higher, timely and reasonable treatment can ensure long-term survival of patients. Worsening RIFLE stage of recipients can predict high mortality when only given LT. SLKT might be a better choice for RIFLE stage 2 or 3 patients than LT alone.

Correlated Emission Lasing in Harmonic Oscillators Coupled via a Single Three-Level Artificial Atom

A single superconducting artificial atom can be used for coupling electromagnetic fields up to the single-photon level due to an easily achieved strong coupling regime. Bringing a pair of harmonic oscillators into resonance with the transitions of a three-level atom converts atomic spontaneous processes into correlated emission dynamics. We present the experimental demonstration of two-mode correlated emission lasing in harmonic oscillators coupled via a fully controllable three-level superconducting quantum system (artificial atom). The correlation of emissions with two different colors reveals itself as equally narrowed linewidths and quenching of their mutual phase diffusion. The mutual linewidth is more than 4 orders of magnitude narrower than the Schawlow-Townes limit. The interference between the different color lasing fields demonstrates that the two-mode fields are strongly correlated.

Verification and evaluation of grain QTLs using RILs from TD70 x Kasalath in rice

Grain size is an important trait that directly influences the yield of rice. Validation and evaluation of grain genes is important in rice genetic studies and for breeding. In a population of 240 recombinant inbred lines (RILs) derived from a cross between an extra-large grain japonica variety TD70 and a small grain indica variety Kasalath, we mapped 19 QTLs controlling grain traits. These QTLs included six cloned grain genes, namely, GW2, GS3, qSW5, qGL3, GS5, and GW8. All of the alleles with the optimal effects on grain size came from TD70, the variety with extra-large grains. To verify these gene loci, we cloned and sequenced GW2, GS3, GW5 (qSW5), qGL3, GS5, GW8, and TGW6 in TD70 and Kasalath, and found several functional polymorphisms in the sequences of the genes. New functional markers for the cloned genes were designed to identify parents and RILs. The contributions of these polymorphisms to the improvement in rice grain size traits were evaluated. Our results indicate that at least six functional polymorphisms have additive effects on grain shape and that one non-functional polymorphism in TGW6 affects grain shape in TD70. The newly designed markers will be useful in further studies to identify functional grain genes. Our findings provide insight into the control of grain size in rice, and they will be of value for improving rice grain yield.

Overexpression of HOXA10 promotes gastric cancer cells proliferation and HOXA10(+)/CD44(+) is potential prognostic biomarker for gastric cancer

Gastric cancer (GC) is a malignant cancer with poor prognosis. This study aims to investigate the roles of homeobox A10 (HOXA10) in GC and the correlations between HOXA10/CD44 expression and GC prognosis. Based on qRT-PCR and Western Blot analyses in 50 pairs of fresh GC samples and adjacent normal samples, it is identified that HOXA10 was significantly up-regulated in GC tissues at mRNA and protein levels. Cell proliferation, migration, and invasion were enhanced in GC cells with overexpressed HOXA10, while inhibited in cells with silenced HOXA10. Through IPA software, HOXA10 was predicted to interact with CD44 via MSN, which was preliminarily confirmed by using Western Blot. Through immunohistochemistry and tissue microarray (N=264), it is found that HOXA10 expression was significantly correlated with tumor size (P=0.011) and CD44 expression (P<0.001), while CD44 expression was significantly correlated with tumor size (P<0.001), depth of tumor invasion (P<0.001), lymph node metastasis (P<0.001), distant metastasis (P=0.001), UICC stage (P<0.001), histological differentiation (P<0.001), and HOXA10 expression (P<0.001). Additionally, the over-all survival and disease-free survival of HOXA10(+)/CD44(+) patients were dramatically decreased in comparison with that of HOXA10(+)/CD44(-), HOXA10(-)/CD44(+), or HOXA10(-)/CD44(-) patients (P<0.001), suggesting that the combinatory expression of HOXA10 and CD44 was correlated with poor GC prognosis. In conclusion, HOXA10 and CD44 might play roles in GC tumorigenesis, metastasis, and invasion. HOXA10(+)/CD44(+) expression might serve as a prognostic biomarker for GC, which needs more studies to validate.

Elevated OCT1 participates in colon tumorigenesis and independently predicts poor prognoses of colorectal cancer patients

Octamer transcription factor 1 (OCT1) was found to influence the genesis and progression of numerous cancers except for colorectal cancer (CRC). This study tried to explore the role of OCT1 in CRC and clarify the association between its expression and patients' clinical outcome. Transcriptional and post-transcriptional expression of OCT1 was detected in CRC cancerous tissues and paired normal mucosae by real-time PCR as well as immunohistochemistry. Moreover, the effect of OCT1 knockdown on CRC cell proliferation was investigated both in vitro and in vivo using Cell Counting Kit-8 assay, colony-forming assay, and mouse tumorigenicity assay. Expression of OCT1 was found to be elevated in CRC. Suppression of OCT1 significantly inhibited CRC cell proliferation both in vitro and in vivo. Furthermore, upregulated level of OCT1 was significantly associated with N stage, M stage, and American Joint Committee on Cancer (AJCC) stage (P = 0.027, 0.014, and 0.002, respectively) as well as differential degree (P = 0.022). By using multivariate Cox hazard model, OCT1 was also shown to be a factor independently predicting overall survival (OS; P = 0.013, hazard ratio = 2.747, 95 % confidence interval 1.125 to 3.715) and disease-free survival (DFS; P = 0.004, hazard ratio = 2.756, 95 % confidence interval 1.191 to 4.589) for CRC patients. Our data indicate that OCT1 carries weight in colorectal carcinogenesis and functions as a novel prognostic indicator and a promising target of anti-cancer therapy for CRC.

Structural maintenance of chromosomes 4 is a predictor of survival and a novel therapeutic target in colorectal cancer

BACKGROUND

Structural maintenance of chromosomes 4 (SMC-4) is a chromosomal ATPase which plays an important role in regulate chromosome assembly and segregation. However, the role of SMC-4 in the incidence of malignancies, especially colorectal cancer is still poorly understood.

MATERIALS AND METHODS

We here used quantitative PCR and Western blot analysis to examine SMC-4 mRNA and protein levels in primary colorectal cancer and paired normal colonic mucosa. SMC-4 clinicopathological significance was assessed by immunohistochemical staining in a tissue microarray (TMA) in which 118 cases of primary colorectal cancer were paired with noncancerous tissue. The biological function of SMC-4 knockdown was measured by CCK8 and plate colony formation assays. Fluorescence detection has been used to detect cell cycling and apoptosis.

RESULTS

SMC-4 expression was significantly higher in colorectal cancer and associated with T stage, N stage, AJCC stage and differentiation. Knockdown of SMC-4 expression significantly suppressed the proliferation of cancer cells and degraded its malignant degree.

CONCLUSIONS

Our clinical and experimental data suggest that SMC-4 may contribute to the progression of colorectal carcinogenesis. Our study provides a new therapeutic target for colorectal cancer treatment.

Musashi-2 promotes hepatitis Bvirus related hepatocellular carcinoma progression via the Wnt/β-catenin pathway

Our recent study observed that the expression of Musashi-2 (MSI2), a member of the Musashi family, was up-regulated in hepatitis B virus (HBV) related hepatocellular carcinoma parenchymal cells. Using quantitative PCR, tissue microarray (TMA) and immunohistochemical staining, we evaluated MSI2 mRNA and protein levels in tumor tissues from patients with different stages of hepatocellular carcinoma with paired adjacent noncancerous sample sets. The following techniques were used to further investigate MSI2 function and its potential molecular mechanism: RNAi, wound healing assay, Transwell assay, quantitative PCR and western blot analysis. Immunohistochemical detection of MSI2 on a TMA containing 106 paired specimens showed that increased cytoplasmic and nuclear MSI2 staining was significantly associated with tumor size, tumor differentiation, recurrence, TNM stage, vessel invasion and Ki-67 proliferative index. Patients with MSI2-positive tumors had a significantly higher disease recurrence rate and poorer survival than patients with MSI2-negative tumors after radical surgery. Based on univariate analysis, MSI2 expression showed an unfavorable influence on both disease-free survival and overall survival. Multivariate analysis revealed that higher MSI2 expression, together with tumor size, tumor differentiation, tumor thrombus, and Ki-67 expression were independent predictors of overall survival. With MSI2 knockdown, hepatoma cell migration and invasion were inhibited and the expression of β-catenin, T cell factor (TCF) and lymphoid enhancer factor (LEF) were dysregulated. Thus, we propose that MSI2 may predict unfavorable outcomes in hepatitis B virus related hepatocellular carcinoma and promote cancer progression via the Wnt/β-catenin signaling pathway.

Efficacy of surgery and adjuvant therapy in older patients with colorectal cancer: a STROBE-compliant article

The present study aimed to assess the efficacy of surgery and adjuvant therapy in older patients (age≥70 years) with colorectal cancer (CRC). Older CRC patients are under-represented in available clinical trials, and therefore their outcomes after receiving surgery and adjuvant therapy are unclear. From two prospective Swedish databases, we assessed a cohort of 1021 patients who underwent curative surgery for stage I, II, or III primary CRC, with or without adjuvant chemotherapy/radiotherapy. Of the patients with colon cancer (n=467), 182 (39%) were aged <70 years, 162 (35%) aged 70 to 80 years, and 123 (26%) were aged ≥80 years. Of rectal cancer patients (n=554), 264 (48%) were aged <70 years, 234 (42%) aged 70 to 80 years, and 56 (10%) aged ≥80 years. Older patients with either colon or rectal cancer had higher comorbidity than did younger patients. Older patients with colon cancer had equivalent postoperative morbidity and 30-day mortality to younger patients. Rectal cancer patients aged ≥80 years had a higher 30-day mortality than younger patients (odds ratio [OR], 2.37; 95% confidence interval [CI], 1.6-4.55; P=0.03). For either colon or rectal cancer, adjuvant chemotherapy compromised the 5-year overall survival (OS) of older patients with stage II disease and had no effect on those with stage III disease. Receiving adjuvant chemotherapy was a poor factor of OS for older patients with either colon (HR 1.88, 95% CI: 1.20-4.35, P=0.03) or rectal cancer (HR 1.72, 95% CI: 1.05-2.26, P=0.004). Preoperative short-course radiotherapy improved both OS and local control for older patients with stage III rectal cancer and had no effect on those with stage II disease. Radiotherapy was a favorable factor for the OS of the older patients with rectal cancer (HR 0.42, 95% CI: 0.21-3.57, P=0.01). In conclusion, Older CRC patients had equal safety of surgery as younger patients, except rectal cancer patients aged ≥80 years that had a higher mortality. Adjuvant 5FU-based chemotherapy did not benefit older CRC patient, while neoadjuvant radiotherapy improved the prognosis of older patients with stage III rectal cancer.

Preparation of bufalin-loaded pluronic polyetherimide nanoparticles, cellular uptake, distribution, and effect on colorectal cancer

A large number of studies have shown that bufalin can have a significant antitumor effect in a variety of tumors. However, because of toxicity, insolubility in water, fast metabolism, short half-life, and other shortcomings, its application is limited in cancer therapy. In this study, we explored the anti-metastatic role of bufalin-loaded pluronic polyetherimide nanoparticles on HCT116 colon cancer-bearing mice. Nanoparticle size, shape, drug loading, encapsulation efficiency, and in vitro drug release were studied. Also, cellular uptake of nanoparticles, in vivo tumor targeting, and tumor metastasis were studied. The nanoparticles had a particle size of about 60 nm and an encapsulation efficiency of 75.71%, by weight. The in vitro release data showed that free bufalin was released faster than bufalin-loaded pluronic polyetherimide nanoparticles, and almost 80% of free bufalin was released after 32 hours. Nanoparticles had an even size distribution, were stable, and had a slow release and a tumor-targeting effect. Bufalin-loaded pluronic polyetherimide nanoparticles can significantly inhibit the growth and metastasis of colorectal cancer.

Ciz1 is a novel predictor of survival in human colon cancer

Cip1-interacting zinc-finger protein1 (Ciz1) is a nuclear matrix protein associated DNA replication factor which has been implicated in breast and lung cancer progression. However, the clinical significance of Ciz1 expression in colon cancer has not been determined. This study aimed to examine Ciz1 expression pattern and its potential as a biomarker of prognosis in colon cancer. Using quantitative PCR, tissue microarray (TMA), and ELISA, we evaluated Ciz1 mRNA and protein levels in tumor tissues from patients with colon cancer and in paired adjacent normal tissues. Ciz1 mRNA expression was significantly upregulated in 22 of 39 paired samples (P < 0.001). Immunohistochemistry on TMA-containing samples from 203 colon cancer patients indicated that Ciz1 protein expression was significantly higher in tumor tissues than in adjacent normal tissues (Stuart-Maxwell test, P < 0.001). Elevated expression of Ciz1 protein was significantly correlated with T stage (P < 0.001), N stage (P = 0.005), M stage (P = 0.021), and AJCC stage (P = 0.002). Multivariate Cox proportion hazard model analysis revealed that Ciz1 expression is an independent prognostic factor for overall time (OS; hazard ratio (HR): 1.76; 95% confidence interval (CI): 1.04-2.98; P = 0.034) and disease-free survival (DFS; HR: 2.02; 95% CI: 1.14-3.58; P = 0.017) of patients with colon cancer after colectomy. Our data suggested that Ciz1 may be involved in colon cancer progression and could serve as a novel predictor of survival for colon cancer patients.

Long non-coding RNA HOTAIR is a powerful predictor of metastasis and poor prognosis and is associated with epithelial-mesenchymal transition in colon cancer

Colon cancer is one of the most frequently diagnosed cancer and the third most fatal malignancy worldwide. HOTAIR, a cancer-associated long non-coding RNA (lncRNA), is a powerful biomarker of metastasis and poor prognosis in a diverse group of cancers. Nevertheless, an understanding of how HOTAIR is involved in colon cancer progression is limited. In the present study, we hypothesized that HOTAIR plays a crucial role in colon cancer development. We evaluated the expression of HOTAIR in 120 colon cancer samples, matched adjacent non-tumor mucosa and 32 lymph node metastasis tissues by real-time PCR. Increased HOTAIR expression was significantly correlated with the depth of tumor invasion, lymph node metastasis, organ metastasis, histological differentiation, vascular invasion and advanced tumor stage. Patients with high HOTAIR expression had higher recurrence rates and reduced metastasis-free and overall survival than patients with low HOTAIR expression. Moreover, our findings revealed that HOTAIR had a limited effect on cell proliferation but significantly promoted colon cancer cell migration and invasion in vitro. Depletion of HOTAIR increased the expression of E-cadherin while concomitantly decreasing expression of vimentin and MMP9. Hence, HOTAIR may be another pleiotropic modulator participating in epithelial-mesenchymal transition (EMT). These results indicate that HOTAIR may also be a valuable predictor for colon cancer management; furthermore, this lncRNA may be a potential target for cancer prevention and treatment.

Combined detection tumor markers for diagnosis and prognosis of gallbladder cancer

AIM: To clarify the value of combined use of markers for the diagnosis of gallbladder cancer and prediction of its prognosis.

METHODS: Serum cancer antigens (CA)199, CA242, carcinoembryonic antigen (CEA), and CA125 levels were measured in 78 patients with gallbladder cancer (GBC), 78 patients with benign gallbladder diseases, and 78 healthy controls using electrochemiluminescence. CA199, CA242, CEA, and CA125 levels and positive rates were analyzed and evaluated pre- and post-operatively. Receiver operator characteristic curves were used to determine diagnostic sensitivity and specificity of GBC. Survival time analysis, including survival curves, and multivariate survival analysis of a Cox proportional hazards model was performed to evaluate independent prognostic factors.

RESULTS: Serum CA242, CA125, and CA199 levels in the GBC group were significantly higher when compared with those in the benign gallbladder disease and healthy control groups (P < 0.01). With a single tumor marker for GBC diagnosis, the sensitivity of CA199 was the highest (71.7%), with the highest specificity being in CA242 (98.7%). Diagnostic accuracy was highest with a combination of CA199, CA242, and CA125 (69.2%). CA242 could be regarded as a tumor marker of GBC infiltration in the early stage. The sensitivity of CA199 and CA242 increased with progression of GBC and advanced lymph node metastasis (P < 0.05). The 78 GBC patients were followed up for 6-12 mo (mean: 8 mo), during which time serum CA199, CA125, and CA242 levels in the recurrence group were significantly higher than in patients without recurrence (P < 0.01). The post-operative serum CA199, CA125, and CA242 levels in the non-recurrence group were significantly lower than those in the GBC group (P < 0.01). Multivariate survival analysis using a Cox proportional hazards model showed that cancer of the gallbladder neck and CA199 expression level were independent prognostic factors.

CONCLUSION: CA242 is a marker of GBC infiltration in the early stage. CA199 and cancer of the gallbladder neck are therapeutic and prognostic markers.

The beneficial effect of metformin on β-cell function in non-obese Chinese subjects with newly diagnosed type 2 diabetes

AIM

Studies with metformin suggest a favourable change in β-cell function over sulphonylureas in the early course of obese type 2 diabetes mellitus (T2DM), but it remains unclear whether a similar effect is observed in non-obese individuals. Here we investigated the effects of metformin or glipizide gastrointestinal therapeutics system extended-release formulation (GITS) on β-cell function in non-obese patients with newly diagnosed T2DM.

METHODS

A total of 160 newly diagnosed patients with fasting glucose 7.0-13.0 mmol/L and body mass index <30 kg/m(2) from five centres in China were randomized to metformin or glipizide GITS for 24 weeks. Early insulin secretion [the ratio of area under the curve (AUC) of insulin to glucose during 0-30 min (InsAUC30 /GluAUC30 )] and insulin sensitivity [Matsuda index (ISIM )] were assessed during the standard meal tolerance test before and after therapy. Plasma glucagon-like peptide-1(GLP-1) and glucagon levels were also measured.

RESULTS

Metformin improved InsAUC30 /GluAUC30 significantly (from 8.1 ± 0.6 pmol/mmol to 10.7 ± 0.7 pmol/mmol, p < 0.05), comparable to results with glipizide GITS. In the metformin-treated lean (body mass index < 25 kg/m(2) ) subgroup, the increase in ISIM was not significant, but the improvement in InsAUC30 /GluAUC30 was of great magnitude. Increased GLP-1 responses during meal tolerance test and decreased fasting glucagon level were observed after metformin treatment. Correlation analysis showed that the improvement of InsAUC30 /GluAUC30 was associated with the changes in HbA1c (r = -0.374, p = 0.000), ISIM (r = 0.356, p = 0.001), and ΔGLP-10-30 (r = 0.225, p = 0.02).

CONCLUSIONS

Metformin improved β-cell function in non-obese subjects with newly diagnosed T2DM, which was partly independent of the change in insulin sensitivity in these subjects. This study provides evidence-based data to support metformin use in non-obese patients with T2DM as the first-line agent, which can improve both insulin sensitivity and β-cell function.

Effect of ursodeoxycholic acid administration after liver transplantation on serum liver tests and biliary complications: a randomized clinical trial

BACKGROUND/AIMS

Endogenous hydrophobic bile acids are suspected to be one of the pathogenetic factors of biliary complications after orthotopic liver transplantation (OLT). This study was designed to investigate the effects of hydrophilic ursodeoxycholic acid (UDCA) administration early after OLT on serum liver tests and the incidence of biliary complications.

METHODS

112 adult patients undergoing OLT from donation after cardiac death (DCD) were randomized to UDCA (13-15 mg/kg/day for 4 weeks; 56 patients) or placebo (56 patients). Serum liver tests and serum bile acids of all patients and biliary bile acids in patients with T-tube drainage were determined during the 4 weeks after OLT. Biliary complications as well as patient and graft survival were analyzed during a mean follow-up of 41.6 months.

RESULTS

UDCA treatment decreased ALT, AST and GGT (p < 0.05) during the 4 weeks after OLT and the incidence of biliary sludge and casts within the 1st year (p < 0.05). However, no differences in the incidence of other biliary complications as well as 1-, 3- and 5-year graft and patient survival were observed.

CONCLUSIONS

UDCA administration early after DCD-OLT improves serum liver tests and decreases the incidence of biliary sludge and casts within the 1st postoperative year but does not affect overall outcome up to 5 years after OLT.

Identification and validation that up-expression of HOXA13 is a novel independent prognostic marker of a worse outcome in gastric cancer based on immunohistochemistry

Homeobox (HOX) gene family is known to be classic examples of the intimate relationship between embryogenesis and tumorigenesis. However, less is known about the involvement of HOX gene family with gastric cancerogenesis. Here, we screened the expression of HOX gene family in gastric cancers and explored the relationships between them by cDNA microarray. We found several differentially expressed HOX genes in gastric cancers, especially HOXA10 (11/12) and HOXA13 (11/12) with significantly higher expression in the cancerous tissues. Furthermore, we validated HOXA13 as a novel prognostic marker in gastric cancer based on immunohistochemistry and statistical analysis. HOXA13 expression was significantly up-regulated in cancerous tissues compared with the corresponding non-cancerous mucosa (P < 0.001). Up-expression of HOXA13 was significantly correlated with T stage (P = 0.002), M stage (P = 0.024), advanced UICC stage (P < 0.001), histological differentiation (P = 0.005), and relapse (P = 0.001). Patients with positive HOXA13 expression had a obviously lower overall survival (OS) and disease-free survival (DFS) rate than patients with negative HOXA13 expression (HR 3.331, 95 % CI 1.722-6.442, P < 0.001; HR 3.289, 95 % CI 1.703-6.351, P < 0.001, respectively). Univariate and multivariate Cox analysis confirmed that HOXA13 could serve as a significant independent prognostic factor for DFS and OS. Therefore, our results indicated that several HOX genes might be closely involved in the process of the gastric tumorigenesis. Furthermore, up-expression of HOXA13 might be associated with highly aggressive phenotype of gastric cancer. HOXA13 was a significant independent prognostic factor and could serve as a putative biomarker for diagnosis and prognosis of gastric cancer.

Prevalence and risk factor for MDR-GNB infection in liver transplantation

Liver transplantation (LT) has emerged as a viable therapy for various end-stage liver diseases. Multi-drug resistant Gram-negative bacilli (MDR-GNB) have emerged as predominant pathogens. The prevalence of MDR-GNB infection has been increasing in LT recipients, especially in early post-LT stages. MDR-GNB infection has become a main cause of death following LT. Since key elements of MDR-GNB infection after LT mainly include the pre-LT severity of underlying disease, technical problems, acute rejection, and so on, appropriate measures, such as improvement of LT technology and management, restriction of antibiotic use and immunosuppressive therapy advancement, should be commenced to prevent and control the occurrence of MDR-GNB infection. A better understanding of the prevalence of and risk factors for MDR-GNB infection complications is needed to improve quality of life and survival rate after LT.

No association between the USP7 gene polymorphisms and colorectal cancer in the Chinese Han population

Colorectal cancer (CRC), now the third most common cancer across the world, is known to aggregate in families. USP7 is a very important protein with an important role in regulating the p53 pathway, which is critical for genomic stability and tumor suppression. We here genotyped eight SNPs within the USP7 gene and conducted a case-control study in 312 CRC patients and 270 healthy subjects in the Chinese Han population. No significant associations were found for any single SNP and CRC risk. Our data eliminate USP7 as a potential candidate gene towards for CRC in the Han Chinese population.

Analysis of Gram-positive bacterial infection in patients following liver transplantation

BACKGROUND

Liver transplantation is the most effective treatment for patients with end-stage liver failure, however infection after transplantation is a serious clinical complication. The purpose of this research was to investigate the molecular epidemiology and the influence of multidrug-resistant Gram-positive infection in patients, following liver transplantation, to provide reference for clinical treatment and prevention of Gram-positive bacterial infection.

METHODS

We isolated and detected bacteria from phlegm, throat swabs, urine, wound or wound secretions, blood, and fecal samples from 221 liver transplant patients in our hospital from January 2007 to April 2010. All isolated bacterial strains were identified and tested by minimal inhibitory concentration (MIC) drug-sensitive detection using the BioMerieux ATB bacterial identification instrument and repetitive extragenic palindromic-polymerase chain reaction (REP-PCR) detection of bacterial homology. Risk factors were calculated by multivariate Logistic regression analysis.

RESULTS

We collected 250 specimens from 221 patients hospitalized following liver transplantation surgery, of which 29 patients developed multiple infections. Sixty-five Gram-positive bacterial strains were isolated from different specimens from 53 infectious patients. We detected 29 multidrug-resistant Gram-positive strains from 29 patients (44.62%), including 20 Staphylococcus aureus (S. aureus) strains (68.97%) and nine Enterococcus strains (31.03%). All 20 S. aureus strains were highly resistant to aminoglycosides (gentamicin), cephalosporins (cefoxitin), quinolones (ciprofloxacin and levofloxacin), lincomycins (clindamycin), penicillin, and erythromycin. The resistance rate reached 100% in some cases. The S. aureus strains were highly sensitive to vancomycin and oxazolidinone (linezolid), with MIC50 < 2 µg/ml for both. The nine Enterococci strains were also highly resistant to aminoglycosides, quinolones, and penicillins, and highly sensitive to vancomycin (MIC50 < 2 µg/ml) and oxazolidinone (MIC50 < 1 µg/ml). Using REP-PCR detection, S. aureus was divided into five genotypes with 14 B-type strains. Enterococcus was divided into 11 genotypes, with two D-type strains, two G-type strains, and two K-type strains. The risk factors for Gram-positive bacterial infection in patients following liver transplantation were preoperative use of antibiotics (OR = 3.949, P = 0.004), high intra-operative blood input (OR = 1.071, P = 0.005), and postoperative renal failure (OR = 5.427, P = 0.043).

CONCLUSIONS

S. aureus and Enterococcus were the main pathogens causing infection following liver transplantation in patients with drug-resistant Gram-positive bacterial infection. The isolated strains were resistant to multiple antibiotics. B-type S. aureus strains were predominant. Reasonable use of antibiotics, decreasing intra-operative blood input, and preventing post-operative renal failure may reduce Gram-positive bacterial infections and the appearance of drug-resistant strains following liver transplantation.

Characterization and primary functional analysis of phenylalanine ammonia-lyase gene from Phyllostachys edulis

Phenylalanine ammonia-lyase (PAL) catalyzes the first reaction in phenylpropanoid pathway leading to the production of phenolic compounds with a wide range of biological functions. The cDNA encoding PAL was isolated from Phyllostachys edulis by reverse transcription-polymerase chain reaction (RT-PCR) and by 5' and 3' rapid amplification of cDNA ends, and was designated as PePAL. The full length of PePAL was 2,503 bp which contained an open reading frame (ORF) encoding a peptide of 701 amino acids, with a theoretic isoelectric point of 6.49 and a calculated molecular mass of 75.7 kDa. PePAL was heterologously expressed in Escherichia coli and the recombinant proteins exhibited both PAL and tyrosine ammonia-lyase (TAL) activities. The optimum temperature and pH of the recombinant PePAL were 50 °C and 8.5-9.0, respectively. The K (m) and V (max) values for L-phenylalanine was calculated as 422 μM and 45.9 nM s⁻¹, while for L-tyrosine were 78 μM and 7.09 nM s⁻¹, respectively. Tissue-specific expression assay showed that PePAL expressed highest in stem and sheath, followed by leaf, and lowest in root. Though the accumulation of PePAL proteins was observed in all these four organs by Western blotting, the highest was detected in leaf. Immunohistochemistry study showed that PePAL was localized primarily in vascular bundles and part of sclerenchyma cells of leaf, sheath and root. These results suggested that PePAL had similar expression pattern and biochemical properties with PALs in other plants, which laid the basis for molecular engineering to improve the quality of bamboo products.

KEY MESSAGE

PePAL was a protein with bifunctional enzyme activities of PAL and TAL as shown in vitro assays, and localized primarily in bamboo vascular bundles.

Development of a low-cost magnetic microfluidic chip for circulating tumour cell capture

The authors have developed a novel fabrication process for a selective micro-magnetic activated cell sorting (MACS) chip based on ferromagnetic material encapsulated micropillars (FMEMs), which is technically simple and low cost. The FMEM produces a high field gradient to magnetically attract, capture and hold cells on its interface. System test simulations were carried out to predict the efficacy of target capture and verify that the actual magnetic particles behaviour agreed well with model predictions. To determine the ability of the novel microMACS chip to capture circulating tumour cells (CTCs), SW620 human colon cancer cells were used in an in vitro flow model system and were able to be captured with the efficiency of 72.8%. The obvious accumulation of CTCs at a certain location on the chip suggested shear stress events at the pillar boundary may influence efficacy, and should be considered in further optimisation efforts.

Downregulation of metallothionein 1F, a putative oncosuppressor, by loss of heterozygosity in colon cancer tissue

PURPOSE

Downregulation of metallothionein (MT) genes has been reported in several tumors with discrepant results. This study is to investigate molecular mechanism of MT gene regulation in colon cancer which is characterized by tumor suppressor gene alterations.

EXPERIMENTAL DESIGN

Integral analysis of microarray data with loss of heterozygosity (LOH) information was employed. Quantitative real-time PCR and immunohistochemistry were used to validate MT isoform expression in colon cancer tissues and cell lines. The effects of MT1F expression on RKO cell survival and tumorigenesis was analyzed. Bisulphite sequencing PCR (BSP) and methylation-specific PCR were employed to detect the methylation status of the MT1F gene in colon cancer tissues and cell lines. DNA sequencing was used to examine the LOH at the MT1F locus.

RESULTS

MT1F, MT1G, MT1X, and MT2A gene expression was significantly downregulated in colon cancer tissue (p<0.05). Exogenous MT1F expression increased RKO cell apoptosis and inhibited RKO cell migration, invasion and adhesion as well as in vivo tumorigenicity. Downregulation of MT1F gene in majority of human colon tumor tissues is mainly through mechanism by loss of heterozygosity (p=0.001) while CpG island methylation of MT1F gene promoter region was only observed in poorly differentiated, MSI-positive RKO and LoVo colon cancer cell lines.

CONCLUSIONS

MT1F is a putative tumor suppressor gene in colon carcinogenesis that is downregulated mainly by LOH in colon cancer tissue. Further studies are required to elucidate a possible role for MT1F downregulation in colon cancer initiation and/or progression.

Multidrug-resistant gram-negative bacterial infections after liver transplantation - spectrum and risk factors

OBJECTIVES

Gram-negative bacilli infections, especially multidrug-resistant gram-negative bacilli infections, are the leading cause of high mortality after liver transplantation. This study sought to investigate the type of infection, infection rate, pathogenic spectrum, antibiotic-resistance profile, risk factors, and epidemiology of multidrug-resistant gram-negative bacterial infection.

METHODS

A retrospective cohort study was conducted and data of 217 liver transplant patients receiving cadaveric livers between January 2007 and April 2010 were analyzed. Antibiotic susceptibility was determined by minimum inhibitory concentration test. Extended-spectrum and metallo-β-lactamase assays were used to analyze β-lactamase-produced isolates, and repetitive-sequence polymerase chain reaction was used to differentiate bacterium subspecies.

RESULTS

Sixty-seven isolates of multidrug-resistant gram-negative bacteria were isolated from 66 infected liver transplant patients. Stenotrophomonas maltophilia (100%, 8/8), Klebsiella pneumoniae (61.5%, 8/13), Enterobacter cloacae (75%, 3/4) and Escherichia coli (81.3%, 13/16) were the most common extended-spectrum β-lactamase-producing bacilli. Metallo-β-lactamase expressing isolates were identified as S. maltophilia (100%, 8/8), Pseudomonas aeruginosa (83.3%, 5/6), Acinetobacter baumannii (95%, 19/20). Significant independent risk factors for multidrug-resistant gram-negative infection were extended use of pre-transplant broad-spectrum antibiotics (OR 9.027, P=0.001) and prolonged (≧72h) endotracheal intubation (OR 3.537, P=0.033).

CONCLUSIONS

To reduce the risk of acquiring MDR gram-negative bacillus infections after liver transplant, control measures are required to limit the use of prophylactic antibiotic in preventing infection during liver transplant and to shorten endotracheal intubation time.

Up-regulation of microRNA-155 promotes cancer cell invasion and predicts poor survival of hepatocellular carcinoma following liver transplantation

PURPOSE

MicroRNAs play important roles in cancer development, progression, and metastasis. The aim of this study was to determine whether altered microRNA-155 expression is associated with hepatocellular carcinoma (HCC) recurrence and prognosis following orthotopic liver transplantation (OLT).

METHODS

Tissue specimens from 100 HCC patients following OLT were recruited. MicroRNA-155 expression levels were detected using quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Kaplan-Meier and Cox proportional regression analyses were utilized to determine the association of microRNA-155 expression with survival of patients. MicroRNA-155 expression levels of two HCC cell lines (HepG2 and SMMC-7721) and normal liver tissue were quantified using qRT-PCR. The potential function of miR-155 on invasiveness was evaluated in the above HCC cell lines.

RESULTS

We found that microRNA-155 expression levels were high in tumor tissues in patients with post-OLT HCC recurrence (n = 45) compared with those in patients with non-recurrence (n = 55) (P = 0.001) and correlated with micro-vascular invasion of HCC tissue samples (P = 0.001). Patients with higher miR-155 expression had significantly poorer recurrence-free survival (RFS, log rank P < 0.001) and overall survival (OS, log rank P < 0.001). Multivariate analysis revealed that high miR-155 expression was an independent predictor of poor prognosis (HR 2.748, P = 0.001 for RFS; HR 5.752, P < 0.001 for OS). In addition, the invasiveness of HCC cells was significantly increased by higher microRNA-155 expression.

CONCLUSIONS

MicroRNA-155 is a candidate oncogenic microRNA and plays an important role in promoting HCC cells invasion. Our findings suggest that microRNA-155 may serve as a novel biomarker for tumor recurrence and survival of HCC patients following OLT.

Up-regulation of microRNA-155 promotes cancer cell invasion and predicts poor survival of hepatocellular carcinoma following liver transplantation

PURPOSE

MicroRNAs play important roles in cancer development, progression, and metastasis. The aim of this study was to determine whether altered microRNA-155 expression is associated with hepatocellular carcinoma (HCC) recurrence and prognosis following orthotopic liver transplantation (OLT).

METHODS

Tissue specimens from 100 HCC patients following OLT were recruited. MicroRNA-155 expression levels were detected using quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Kaplan-Meier and Cox proportional regression analyses were utilized to determine the association of microRNA-155 expression with survival of patients. MicroRNA-155 expression levels of two HCC cell lines (HepG2 and SMMC-7721) and normal liver tissue were quantified using qRT-PCR. The potential function of miR-155 on invasiveness was evaluated in the above HCC cell lines.

RESULTS

We found that microRNA-155 expression levels were high in tumor tissues in patients with post-OLT HCC recurrence (n = 45) compared with those in patients with non-recurrence (n = 55) (P = 0.001) and correlated with micro-vascular invasion of HCC tissue samples (P = 0.001). Patients with higher miR-155 expression had significantly poorer recurrence-free survival (RFS, log rank P < 0.001) and overall survival (OS, log rank P < 0.001). Multivariate analysis revealed that high miR-155 expression was an independent predictor of poor prognosis (HR 2.748, P = 0.001 for RFS; HR 5.752, P < 0.001 for OS). In addition, the invasiveness of HCC cells was significantly increased by higher microRNA-155 expression.

CONCLUSIONS

MicroRNA-155 is a candidate oncogenic microRNA and plays an important role in promoting HCC cells invasion. Our findings suggest that microRNA-155 may serve as a novel biomarker for tumor recurrence and survival of HCC patients following OLT.

Generation and analysis of expressed sequence tags from a normalized cDNA library of young leaf from Ma bamboo (Dendrocalamus latiflorus Munro)

Ma bamboo (Dendrocalamus latiflorus Munro) belongs to Dendrocalamus genus, Bambusease tribe, Bambusoideae subfamily, Poaceae family. It is a representative species of clumping bamboo, and a principal commercial species for various construction purposes using mature culms and for human consumption using young shoots. A normalized cDNA library was constructed from young leaves of Ma bamboo and 9,574 high-quality ESTs were generated, from which 5,317 unigenes including 1,502 contigs and 3,815 singletons were assembled. The unigenes were assigned into different gene ontology (GO) categories and summarized into 13 broad biologically functional groups according to similar functional characteristics or cellular roles by BLAST search against public databases. Eight hundred and ninety-one unigenes were assigned by KO identifiers and mapped to six KEGG biochemical pathways. The transcripts involved in biosynthesis of secondary metabolites such as cytochrome 450, flavonol synthase/flavanone 3-hydroxylase, and dihydroflavonol-4-reductase were well represented by 14 unigenes in the unigene set. The candidate genes involved in phytohormone metabolism, signal transduction and encoding cell wall-associated receptor kinases were also identified. Sixty-seven unigenes related to plant resistance (R) genes, including RPP genes, RGAs and RDL/RF genes, were discovered. These results will provide genome-wide knowledge about the molecular physiology of Ma bamboo young leaves and tools for advanced studies of molecular mechanism underlying leaf growth and development.