Postoperative chemoradiotherapy improves survival in esophageal squamous cell cancer with extracapsular lymph node extension

In esophageal squamous cell carcinoma (ESCC), extracapsular extention (ECE) in metastatic lymph nodes portends high rate of recurrence and poor prognosis. To our knowledge, the effectiveness of postoperative chemoradiotherapy (CRT) in these patients has never been investigated. In this retrospective study, we compared the outcomes of surgery with or without postoperative chemoradiotherapy in ESCC patients with ECE. From 2008 to 2009, 90 ECSS patients with ECE were included. Among those patients, 47 only received curative surgery alone, and 43 received additional postoperative concurrent CRT which consisted of radiotherapy (median dose 50 Gy) and chemotherapy (5-fluorouracil 1000 mg/m(2), days 1-4 and 29-32; cisplatinum 25 mg/m(2), days 1-3 and 29-31). Patients treated with postoperative CRT had significantly more T3/4 tumors (p=0.023). Based on log-rank stratified by T stage, postoperative adjuvant CRT significantly improved the overall survival (p=0.017) and progression free survival (p=0.002). In multivariate analysis, adjuvant CRT was identified as an independent prognostic factor (HR=0.494, CI 0.290-0.844, p=0.010). Compared with surgery alone, the CRT group had significantly fewer cases of regional recurrence (P=0.048) and overall recurrence (P=0.024). However, there was no significant difference in distant metastasis between two groups (P=0.755). In conclusion, our data suggest that the postoperative adjuvant CRT might be beneficial in selected subgroups of ESCC patients with ECE. To further verify these results, a prospective trial with a large sample size is needed.

Chaperone-like protein p32 regulates ULK1 stability and autophagy

Mitophagy mediates clearance of dysfunctional mitochondria, and represents one type of mitochondrial quality control, which is essential for optimal mitochondrial bioenergetics. p32, a chaperone-like protein, is crucial for maintaining mitochondrial membrane potential and oxidative phosphorylation. However, the relationship between p32 and mitochondrial homeostasis has not been addressed. Here, we identified p32 as a key regulator of ULK1 stability by forming complex with ULK1. p32 depletion potentiated K48-linked but impaired K63-linked polyubiquitination of ULK1, leading to proteasome-mediated degradation of ULK1. As a result, silencing p32 profoundly impaired starvation-induced autophagic flux and the clearance of damaged mitochondria caused by mitochondrial uncoupler. Importantly, restoring ULK1 expression in p32-depleted cells rescued autophagy and mitophagy defects. Our findings highlight a cytoprotective role of p32 under starvation conditions by regulating ULK1 stability, and uncover a crucial role of the p32-ULK1-autophagy axis in coordinating stress response, cell survival and mitochondrial homeostasis.Cell Death and Differentiation advance online publication, 24 April 2015; doi:10.1038/cdd.2015.34.

Chaperone-like protein p32 regulates ULK1 stability and autophagy

Mitophagy mediates clearance of dysfunctional mitochondria, and represents one type of mitochondrial quality control, which is essential for optimal mitochondrial bioenergetics. p32, a chaperone-like protein, is crucial for maintaining mitochondrial membrane potential and oxidative phosphorylation. However, the relationship between p32 and mitochondrial homeostasis has not been addressed. Here, we identified p32 as a key regulator of ULK1 stability by forming complex with ULK1. p32 depletion potentiated K48-linked but impaired K63-linked polyubiquitination of ULK1, leading to proteasome-mediated degradation of ULK1. As a result, silencing p32 profoundly impaired starvation-induced autophagic flux and the clearance of damaged mitochondria caused by mitochondrial uncoupler. Importantly, restoring ULK1 expression in p32-depleted cells rescued autophagy and mitophagy defects. Our findings highlight a cytoprotective role of p32 under starvation conditions by regulating ULK1 stability, and uncover a crucial role of the p32-ULK1-autophagy axis in coordinating stress response, cell survival and mitochondrial homeostasis.

Isolation of lactic acid bacteria from pao cai, a Chinese traditional fermented vegetable, with inhibitory activity against Salmonella associated with fresh-cut apple, using a modelling study

AIMS

To isolate lactic acid bacteria (LAB) from pao cai, a Chinese traditional fermented vegetable, with outstanding inhibitory activity against Salmonella inoculated on fresh-cut apple, using a modelling method.

METHODS AND RESULTS

Four kinds of pao cai were selected. A total of 122 isolates exhibited typical LAB characteristics: Gram-positive and catalase negative, among which 104 (85·24%) colonies showed antibacterial activity against Salmonella by the well diffusion assay. Four colonies showing maximum antibacterial radius against Salmonella were selected to co-inoculate with Salmonella on fresh-cut apple and stored at 10°C, further identified as three strains of Lactobacillus plantarum and one strain of Lactobacillus brevis by 16s rRNA gene sequence analysis. The modified Gompertz model was employed to analyse the growth of the micro-organisms on apple wedges. Two of the four selected strains showed antagonistic activity against Salmonella on fresh-cut apple, one of which, RD1, exhibited best inhibitory activity (Salmonella were greatly inhibited when co-inoculated with RD1 at 10°C at 168 h). No deterioration in odour or appearance of the apple piece was observed by the triangle test when fresh-cut apple was inoculated with RD1.

CONCLUSIONS

The mathematical modelling method is essential to select LAB with outstanding inhibitory activity against Salmonella associated with fresh-cut apple. LAB RD1 holds promise for the preservation of fresh-cut apple.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study provided a new method on fresh-cut product preservation. Besides, to make the LAB isolating procedure a more correct one, this study first added the mathematical modelling method to the isolating procedure.

Clinical significance of microRNA-24 expression in esophageal squamous cell carcinoma

microRNA-24 has been reported to participate in tumorgenesis and progression by several signaling pathways in various tumors. However, its potential as a serum diagnostic factor and predictive biomarker for esophageal squamous cell carcinoma (ESCC) has not been studied. In the present study, serum samples were collected from 105 pathologically proven ESCC patients and 30 healthy volunteers. All patients were treated with concurrent chemotherapy and radiotherapy. Real-time polymerase chain reaction was carried out to measure the serum miR-24 expression level in all patients and volunteers. The data were compared among radio-sensitive group (CR+PR, 62 patients), radio-resistant group (SD+PD, 43 patients) and healthy volunteers to elucidate the diagnostic value of serum miR-24 testing for ESCC and the predictive value of miR-24 expression of treatment response. In the result, of the 105 ESCC patients enrolled in the study, 62 patients achieved partial or complete response. The serum miR-24 level in ESCC patients is 4.82 times as high as that in healthy subjects(P<0.01), indicating that serum miR-24 expression could be an excellent diagnostic factor. The mean miR-24 serum levels differ by 2.05 folds between radiosensitive group and radioresistant group, indicating that it may serve as a biomarker for predicting the response of ESCC patient to CRT. Furthermore, the responsiveness of therapy is significantly correlated with Cyfra21-1(P<0.05), serum miR-24 level (P<0.05) and the myelosuppression (P<0.01). In the prsent study, we come to the conclusion that serum miR-24 has the potential to serve as a noninvasive biomarker for both ESCC diagnosis and predicting treatment responses to concurrent chemo-radiation therapy. ESCC patients with lower Cyfra21-1, higher miR-24, and severer myelosupression were much more sensitive to CRT.

KEYWORDS

miR-24 expression, esophageal squamous cell carcinoma, chemo-radiation therapy, radiosensitivity.

Cost-effectiveness of alternative strategies for integrating MRI into breast cancer screening for women at high risk

BACKGROUND

Magnetic resonance imaging (MRI) is recommended for women at high risk for breast cancer. We evaluated the cost-effectiveness of alternative screening strategies involving MRI.

METHODS

Using a microsimulation model, we generated life histories under different risk profiles, and assessed the impact of screening on quality-adjusted life-years, and lifetime costs, both discounted at 3%. We compared 12 screening strategies combining annual or biennial MRI with mammography and clinical breast examination (CBE) in intervals of 0.5, 1, or 2 years vs without, and reported incremental cost-effectiveness ratios (ICERs).

RESULTS

Based on an ICER threshold of $100,000/QALY, the most cost-effective strategy for women at 25% lifetime risk was to stagger MRI and mammography plus CBE every year from age 30 to 74, yielding ICER $58,400 (compared to biennial MRI alone). At 50% lifetime risk and with 70% reduction in MRI cost, the recommended strategy was to stagger MRI and mammography plus CBE every 6 months (ICER=$84,400). At 75% lifetime risk, the recommended strategy is biennial MRI combined with mammography plus CBE every 6 months (ICER=$62,800).

CONCLUSIONS

The high costs of MRI and its lower specificity are limiting factors for annual screening schedule of MRI, except for women at sufficiently high risk.

Pathological analysis of extracapsular extension of metastatic lymph node and its potential impact on nodal clinical target volume in the radiotherapy of esophageal squamous cell carcinoma

There is no consensus regarding the clinical target volume (CTV) margins which surround the gross tumor volume of metastatic lymph nodes (LN) in radiotherapy of esophageal squamous cell carcinoma (ESCC). This study retrospectively assessed the distance of extracapsular extension (ECE) of metastatic LN in thoracic ESCC and defined nodal CTV margins. Histological sections of metastatic LNs from 217 patients with thoracic ESCC were re-examined. The incidence and maximal distance of ECE of metastatic LNs were assessed. The relationships between ECE and clinicopathologic features were also investigated. The ECE was found in 37.3% of patients (81/217) and 23.1% of metastatic LN (159/689), and the incidences had a significant relationship with N stage and LN size. The median distance of ECE was 1.0 mm (range, 0.2-9.7 mm). The distance of ECE showed a positive correlation with LN size (Spearman's correlation coefficient = 0.419; p<0.001). The ECE distances of LN with <10 mm diameter were significantly smaller than LN with 10-30 mm diameter (p<0.001). The 95th percentiles of ECE distances for these two groups were 3 mm and 5 mm, respectively. For pathologic LN <10 mm in diameter, a 3-mm CTV margin appears to be adequate to encompass 95% of the microscopic ECE, and for LN 10-30 mm, a 5-mm CTV margin is recommended.

Coverage effect on reactivity can be more complicated than what you believe: H2 dissociation on H-precovered Pd(111)

A systematic investigation based on density-functional-theory calculations is presented for elucidating the effect of adatoms on the energetics of H2 dissociation on H-precovered Pd(111) surfaces. Surprisingly, we found that the H-adatoms do not only have a poisoning effect but can also promote H2 dissociation when they are adsorbed on sites which are sufficiently far from the dissociating H2 molecule. The presence of these antagonistic effects produces many crossovers of the minimum energy profiles for H2 dissociation when coverage is varied and thus leads to a quite perplexing picture for the adatom effects. We devised a sorting procedure which allows for rationalizing nicely the influence of H-adatoms on the energetics of H2 dissociation on H-precovered Pd(111) surfaces.

Meta-analysis of the effects of endoscopy with narrow band imaging in detecting dysplasia in Barrett's esophagus

Narrow band imaging (NBI) is a real-time imaging technique. The aim of this meta-analysis was to estimate the sensitivity, specificity, and diagnostic accuracy on the role of NBI in the detection and characterization of specialized intestinal metaplasia (SIM), high-grade dysplasia (HGD) in the Barrett's esophagus. We identified studies by performing a literature search of Medline, EMBASE, and the Cochrane Library databases up to May 2013. We performed data analysis using Meta-DiSc (version 1.4) software. To assess study quality and potential for bias, we used the Quality Assessment of Diagnostic Accuracy Studies-2 tool (QUADAS-2). Overall, seven eligible studies including over 3988 lesions of 502 patients were retrieved. The results showed that endoscopic diagnosis of dysplasia performed using NBI has a high diagnostic performance, with an area under the summary receiver operating characteristic (SROC) curve near 0.90 both in HGD lesions and SIM lesions. We also found that NBI has a sensitive and specificity of 0.91 (95% confidence interval [CI] = 0.86-0.94) and 0.85 (95% CI = 0.76-0.92) on a per-patient element, and 0.97 (95% CI = 0.95-0.98) and 0.64 (95% CI = 0.59-0.68) on a per-lesion element for SIM diagnosis, respectively. The pooled per-patient sensitivity and specificity for identifying HGD are 0.91 (95% CI = 0.75-0.98) and 0.95 (95% CI = 0.91-0.97). The pooled per-lesion sensitivity and specificity for identifying HGD are 0.69 (95% CI = 0.63-0.74) and 0.90 (95% CI = 0.88-0.91). In conclusion, we found that endoscopic diagnosis with NBI is an accurate test to diagnosis dysplasia of Barrett's esophagus.

The histone methyltransferase ESET is required for the survival of spermatogonial stem/progenitor cells in mice

Self-renewal and differentiation of spermatogonial stem cells (SSCs) are the foundation of spermatogenesis throughout a male's life. SSC transplantation will be a valuable solution for young male patients to preserve their fertility. As SSCs in the collected testis tissue from the patients are very limited, it is necessary to expansion the SSCs in vitro. Previous studies suggested that histone methyltransferase ERG-associated protein with SET domain (ESET) represses gene expression and is essential for the maintenance of the pool of embryonic stem cells and neurons. The objective of this study was to determine the role of ESET in SSCs using in vitrocell culture and germ cell transplantation. Cell transplantation assay showed that knockdown of ESET reduced the number of seminiferous tubules with spermatogenesis when compared with that of the control. Knockdown of ESET also upregulated the expression of apoptosis-associated genes (such as P53, Caspase9, Apaf1), whereas inhibited the expression of apoptosis-suppressing genes (such as Bcl2l1, X-linked inhibitor of apoptosis protein). In addition, suppression of ESET led to increase in expression of Caspase9 and activation of Caspase3 (P17) as well as cleavage of poly (ADP-ribose) polymerase. Among the five ESET-targeting genes (Cox4i2, spermatogenesis and oogenesis Specific Basic Helix-Loop-Helix 2, Nobox, Foxn1 and Dazl) examined by ChIP assay, Cox4i2 was found to regulate SSC apoptosis by the rescue experiment. BSP analyses further showed that DNA methylation in the promoter loci of Cox4i2was influenced by ESET, indicating that ESET also regulated gene expression through DNA methylation in addition to histone methylation. In conclusion, we found that ESET regulated SSC apoptosis by suppressing of Cox4i2 expression through histone H3 lysine 9 tri-methylation and DNA methylation. The results obtained will provide unique insights that would broaden the research on SSC biology and contribute to the treatment of male infertility.

Note: a Piezo Tip/Tilt Platform: structure, kinematics, and experiments

A Piezo Tip/Tilt Platform (PT(2)P) is presented with its structure, kinematics, and preliminary experiments. Two essential models of the presented PT(2)P, an equivalent hinge of the flexure hinge and a simplified model of the transmission mechanism, are discussed with the analysis on the structure of the PT(2)P. Based on these models, the inverse kinematics of the PT(2)P is derived. Two experiments are conducted on a prototype of the PT(2)P. The kinematic model is verified with experimental results, which also indicate that the resolution and the repeatability of the PT(2)P is, respectively, better than 0.50 μrad and 0.25 μrad.

Degradation of acetochlor by a bacterial consortium of Rhodococcus sp.T3-1, Delftia sp.T3-6 and Sphingobium sp.MEA3-1

Owing to acetochlor persistence in the environment and its perceptible threats to the ecosystem and human health, it is urgent to search for effective approaches to decontaminate acetochlor. In this study, an acetochlor-degrading enrichment culture was obtained by continuous enrichment from acetochlor-contaminated soil and named T3. T3 could completely degrade 100 mg l(-1) acetochlor and butachlor within 6 days. Two bacterial strains Rhodococcus sp.T3-1 and Delftia sp.T3-6 and one strain Sphingobium sp.MEA3-1 were isolated and identified from T3 by using acetochlor and MEA as sole carbon source, respectively. These three bacteria could completely mineralize acetochlor by the cooperative metabolism. The biochemical pathway of acetochlor degradation by these three bacteria in a consortium was proposed: acetochlor to 2'-methyl-6'-ethyl-2-chloroacetanilide (CMEPA) by Rhodococcus sp. T3-1, CMEPA to 2-methyl-6-ethyl aniline (MEA) by Delftia sp.T3-6 and MEA by Sphingobium sp.MEA3-1 based on the identified degradation intermediates. Under laboratory conditions, the consortium was effective in the acetochlor mineralization.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study presents a bacterial consortium consisting of Rhodococcus sp.T3-1, Delftia sp.T3-6 and Sphingobium sp.MEA3-1 could completely mineralize acetochlor by biochemical cooperation. The study reveals the metabolic mechanism of acetochlor biodegradation and highlights the potential of the bacterial consortium for cleaning up acetochlor and its metabolites subsisting in the environment.

Towards bond selective chemistry from first principles: methane on metal surfaces

Controlling bond-selective chemical reactivity is of great importance and has a broad range of applications. Here, we present a molecular dynamics study of bond selective reactivity of methane and its deuterated isotopologues (i.e., CH(4-x)D(x), x=0,1,2,3,4) on Ni(111) and Pt(111) from first principles calculations. Our simulations allow for reproducing the full C-H bond selectivity recently achieved experimentally via mode-specific vibrational excitation and explain its origin. Moreover, we also predict the hitherto unexplored influence of the molecular translational energy on such a selectivity as well as the conditions under which the full selectivity can be realized for the a priori less active C-D bond.

Infectivity, transmission, and pathology of human-isolated H7N9 influenza virus in ferrets and pigs

The emergence of the H7N9 influenza virus in humans in Eastern China has raised concerns that a new influenza pandemic could occur. Here, we used a ferret model to evaluate the infectivity and transmissibility of A/Shanghai/2/2013 (SH2), a human H7N9 virus isolate. This virus replicated in the upper and lower respiratory tracts of the ferrets and was shed at high titers for 6 to 7 days, with ferrets showing relatively mild clinical signs. SH2 was efficiently transmitted between ferrets via direct contact, but less efficiently by airborne exposure. Pigs were productively infected by SH2 and shed virus for 6 days but were unable to transmit the virus to naïve pigs or ferrets. Under appropriate conditions, human-to-human transmission of the H7N9 virus may be possible.

Design methodology and performance analysis of application-oriented flexure hinges

Flexure hinges are widely employed in miniature and ultra-precision equipments with the development of precision engineering. In this paper, Castigliano's theorem and Labotto quadrature formula are utilized to derive the compliance matrix. An exclusive longitudinal section of corner-filleted flexure hinges is proposed and the curve of the cross-section is expressed by basic design parameters (r0, d, and l) and machining error parameter (η). The influences of parameters are analyzed by the defined evaluation indexes, i.e., rotation capacity, relative flexibility, and relative rotation error, which are used to assess the quality of flexure hinges. The analysis results indicate small d and optimized values of r0, l, and η will improve flexure hinges' performances. The proposed method is verified by finite element method and experiments within a 5% margin of error.

Obesity, diabetes, and survival outcomes in a large cohort of early-stage breast cancer patients

BACKGROUND

To determine the relationship between obesity, diabetes, and survival in a large cohort of breast cancer patients receiving modern chemotherapy and endocrine therapy.

PATIENTS AND METHODS

We identified 6342 patients with stage I-III breast cancer treated between 1996 and 2005. Patients were evaluated according to body mass index (BMI) category and diabetes status.

RESULTS

In a multivariate model adjusted for body mass index, diabetes, medical comorbidities, patient- and tumor-related variables, and adjuvant therapies, relative to the normal weight, hazard ratios (HRs) for recurrence-free survival (RFS), overall survival (OS), and breast cancer-specific survival (BCSS) for the overweight were 1.18 [95% confidence interval (CI) 1.02-1.36], 1.20 (95% CI 1.00-1.42), and 1.21 (95% CI 0.98-1.48), respectively. HRs for RFS, OS, and BCSS for the obese were 1.13 (95% CI 0.98-1.31), 1.24 (95% CI 1.04-1.48), and 1.23 (95% CI 1.00-1.52), respectively. Subset analyses showed these differences were significant for the ER-positive, but not ER-negative or HER2-positive, groups. Relative to nondiabetics, HRs for diabetics for RFS, OS, and BCSS were 1.21 (95% CI 0.98-1.49), 1.39 (95% CI 1.10-1.77), and 1.04 (95% CI 0.75-1.45), respectively.

CONCLUSIONS

In patients receiving modern adjuvant therapies, obesity has a negative impact on RFS, OS, and BCSS; and diabetes has a negative impact on RFS and OS. Control of both may be important to improving survival in obese and diabetic breast cancer patients.