Novel stent in the palliation of malignant esophageal strictures: a retrospective study

The placement of metal stents is often used as a palliative treatment for malignant esophageal stenosis. We designed a novel stent that has been used clinically since 2011, and we therefore performed a retrospective study to compare the therapeutic effects of this novel metal stent to a conventional partially covered metal stent in patients with malignant esophageal strictures. The records of 201 consecutive patients who underwent placement of either the conventional partially covered metal stents (Group A, n = 92) or the new metal stents (Group B, n = 109) in the Endoscopy Center of General Hospital of Chengdu Military Command from October 2008 to March 2013 were reviewed. The median dysphagia score significantly improved in both groups 1 week following stent placement (P < 0.001). No significant differences were observed in success rate (P = 0.910) or the complication rate (P = 0.426) between groups. Six months after stent placement, recurrent dysphagia due to stent migration, tissue ingrowth or overgrowth or food obstruction occurred in 45% and 29% of patients in the conventional stent and new stent groups, respectively. The results of this retrospective study indicate that the new modified self-expandable metal stents (SEMS) is at least as safe and effective as the conventional partially covered SEMS in treatment of malignant esophageal strictures.

[Efficacy of esophageal cancer screening in high risk population: results of 105 561 subjects in Sichuan province]

Objective: To analyze the efficacy of endoscopic screening for esophageal cancer in high risk population from high risk areas in order to provide scientific basis for evaluation of the results of early diagnosis and treatment of esophageal cancer. Methods: Ten high incidence cities and counties of esophageal cancer in Sichuan province were included in this study. Subjects aged 40-69 years were selected to participate in the endoscopic screening based on the cluster sampling, and the screening-positive subjects were further confirmed by pathological examination. Results: A total of 105 561 subjects were screened during 2006-2014 in 10 cities and counties in Sichuan Province. The detection rate of precancerous lesions was 5.53% (5 841/105 561), and the positive detection rate was 1.13% (1 193/105 561). The overall detection rates of low-grade hyperplasia, moderate hyperplasia, high-grade hyperplasia/carcinoma in situ, early esophageal cancer and invasive carcinoma were 3.87% (4 089/105 561), 1.66% (1 752/105 561), 0.77% (816/105 561), 0.08% (84/105 561) and 0.28% (293/105 561), respectively. The detection rates of all lesions in males were significantly higher than those in females (P<0.05), and were gradually increased with age (P<0.05). Conclusions: At these ten cities and counties in Sichuan Province with high incidence of esophageal cancer, the endoscopic screening has good effect. There are considerable numbers of patients aged 40-69 with precancerous lesions from the high risk areas. Improving the follow-up work of the population with precancerous lesions will achieve better results of early diagnosis and early treatment.

Selective-releasing-affected lubricant mechanism of a self-assembled MoS2/Mo–S–C nanoperiod multilayer film sliding in diverse atmospheres

A self-assembled MoS₂/Mo–S–C multilayer film prepared by r.f. co-sputtering of MoS₂ and graphite targets was tribotested in diverse sliding atmospheres, and the lubricant mechanism and its correlations to the selective releasing behavior of non-lubricant component were analyzed in detail.

[Cerebral infarction in a patient with primary Sjogren's syndrome: a case report and literature review]

Sjogren's syndrome (SS) is a chronic autoimmune disorder characterized by lymphocytes infiltration in the exocrine glands. Central nervous system complications of primary SS are not rare, but ischemic stroke has been rarely reported. Here we report a 43-year-old female with a two-year history of primary SS, presenting with sudden cerebral infarction. Her primary SS was diagnosed on the basis of clinical features, high levels of serum anti-SSA and anti-SSB antibodies, salivary gland secretion evaluation and positive sublingual gland biopsy results. Magnetic resonance imaging revealed infarct lesions in the parietal and occipital lobes, as well as in the left basal ganglia. Magnetic resonance angiography showed a remarkable stenosis in the left middle cerebral artery. Other differential diagnoses were ruled out. Corticosteroid and immunosuppressor, together with anti-platelet and statin were effective, and the patient recovered quickly without sequelae. Based on these findings, vasculitis due to primary SS should be considered among the causes of stroke. The literature was reviewed and the relationship between primary SS and cerebral infarction explored. The pathogenesis of ischemic stroke in primary SS is still unknown and warrants further studies.

Aluminium foil as a single-use substrate for MALDI-MS fingerprinting of different melanoma cell lines

Herein, we present the intact cell matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) for the fingerprinting of human melanoma cancer cell lines grown on aluminium foil.

Electronic and magnetic properties of epitaxial perovskite SrCrO₃(0 0 1)

We have investigated the intrinsic properties of SrCrO3 epitaxial thin films synthesized by molecular beam epitaxy. We find compelling evidence that SrCrO3 is a correlated metal. X-ray photoemission valence band and O K-edge x-ray absorption spectra indicate a strongly hybridized Cr3d-O2p state crossing the Fermi level, leading to metallic behavior. Comparison between valence band spectra near the Fermi level and the densities of states calculated using density functional theory (DFT) suggests the presence of coherent and incoherent states and points to strong electron correlation effects. The magnetic susceptibility can be described by Pauli paramagnetism at temperatures above 100 K, but reveals antiferromagnetic behavior at lower temperatures, possibly resulting from orbital ordering.

Identification and characterization of the novel Col10a1 regulatory mechanism during chondrocyte hypertrophic differentiation

The majority of human skeleton develops through the endochondral pathway, in which cartilage-forming chondrocytes proliferate and enlarge into hypertrophic chondrocytes that eventually undergo apoptosis and are replaced by bone. Although at a terminal differentiation stage, hypertrophic chondrocytes have been implicated as the principal engine of bone growth. Abnormal chondrocyte hypertrophy has been seen in many skeletal dysplasia and osteoarthritis. Meanwhile, as a specific marker of hypertrophic chondrocytes, the type X collagen gene (COL10A1) is also critical for endochondral bone formation, as mutation and altered COL10A1 expression are often accompanied by abnormal chondrocyte hypertrophy in many skeletal diseases. However, how the type X collagen gene is regulated during chondrocyte hypertrophy has not been fully elucidated. We have recently demonstrated that Runx2 interaction with a 150-bp mouse Col10a1 cis-enhancer is required but not sufficient for its hypertrophic chondrocyte-specific reporter expression in transgenic mice, suggesting requirement of additional Col10a1 regulators. In this study, we report in silico sequence analysis of this 150-bp enhancer and identification of its multiple binding factors, including AP1, MEF2, NFAT, Runx1 and TBX5. Using this enhancer as bait, we performed yeast one-hybrid assay and identified multiple candidate Col10a1-interacting genes, including cyclooxygenase 1 (Cox-1) and Cox-2. We have also performed mass spectrometry analysis and detected EF1-alpha, Fus, GdF7 and Runx3 as components of the specific complex formed by the cis-enhancer and nuclear extracts from hypertrophic MCT (mouse chondrocytes immortalized with large T antigen) cells that express Col10a1 abundantly. Notably, some of the candidate genes are differentially expressed in hypertrophic MCT cells and have been associated with chondrocyte hypertrophy and Runx2, an indispensible Col10a1 regulator. Intriguingly, we detected high-level Cox-2 expression in hypertrophic MCT cells. Electrophoretic mobility shift assay and chromatin immunoprecipitation assays confirmed the interaction between Cox-2 and Col10a1 cis-enhancer, supporting its role as a candidate Col10a1 regulator. Together, our data support a Cox-2-containing, Runx2-centered Col10a1 regulatory mechanism, during chondrocyte hypertrophic differentiation.

Effects of surface defects on two-dimensional electron gas at NdAlO3/SrTiO3 interface

Density functional theory calculations of NdAlO₃/SrTiO₃ heterostructure show that two-dimensional electron gas (2-DEG) is produced at the interface with a built-in potential of ~0.3 eV per unit cell. The effects of surface defects on the phase stability and electric field of 2-DEG have been investigated. It is found that oxygen vacancy is easily to form on the NdAlO₃(001) surface, with a low threshold displacement energy and a low formation energy. This point defect results in surface reconstruction and the formation of a zigzag -Al-O-Al- chain, which quenches the built-in potential and enhances the carrier density significantly. These results will provide fundamental insights into understanding how surface defects influence the electronic behavior of 2-DEG and tuning their electronic properties through surface modification.

Silencing of Jagged1 inhibits cell growth and invasion in colorectal cancer

Dysregulated Notch signaling has a critical role in the tumorigenesis. Jagged1, a Notch ligand, is overexpressed in various human cancers. Recent studies revealed the involvement of Jagged1 in colorectal cancer (CRC) development. These basic studies provide a promising potential for inhibition of the Notch pathway for the treatment of CRC. Herein, we aimed to investigate the consequences of targeting Jagged1 using shRNA on CRC both in vitro and in vivo to test their potential to inhibit this key element for CRC treatment. We found that downregulation of Jagged1 with lentiviral Jagged1-shRNA resulted in decreased colon cancer cell viability in vitro, most likely mediated through reduced cell proliferation. Importantly, Jagged1 knockdown induced G₀/G₁ phase cell cycle arrest, with reduced Cyclin D1, Cyclin E and c-Myc expression. Silencing of Jagged1 reduced the migration and invasive capacity of the colon cancer cells in vitro. Furthermore, colon cancer cells with knockdown of Jagged1 had much slower growth rate than control cells in a xenograft mouse model in vivo, with a marked downregulation of cell proliferation markers (PCNA, Ki-67, and c-Myc) and metastasis markers (MMP-2 and MMP-9). These findings rationalize a mechanistic approach to CRC treatment based on Jagged1-targeted therapeutic development.

Water decoction of coptidis rhizoma prevents oxidative damage in erythrocytes of mice

Coptidis Rhizoma (Coptis chinensis) has been reported to have antioxidative effect on hemolysis of erythrocytes induced by acetylphenylhydrazine in mice and rats. However, the ability of Coptidis Rhizoma to protect structure and function of erythrocytes membrane and morphology of erythrocytes against oxidative damage remains unknown. In this study, we undertook a characterization of antioxidative activity in erythrocytes membrane of Coptidis Rhizoma using an in vivo model of acetylphenylhydrazine-induced mice together with in vitro studies with 2,2-azo-bis (2-amidinopropane) dihydrochloride-induced erythrocytes for further morphology characterization. Acetylphenylhydrazine-induced mice were treated intragastrically with Coptidis Rhizoma at doses of 0.3, 0.6, and 1.2 g/kg per day for 3 days and at the dose of 0.6 and 1.2 g/kg it showed that there was an increasing trend in membranes cytoskeletal proteins of band I-IV, especially a significant upregulation in band II. Significant increase in phosphatidylserine and phosphatidylcholine content at the dose of 1.2 g/kg Coptidis Rhizoma was obsereved. At all doses of Coptidis Rhizoma, the declined membrane fluidity of acetylphenylhydrazine-induced mice was significantly increased. In addition, at the dose of 1.2 g/kg Coptidis Rhizoma treatment showed a significant increase in Ca²⁺/Mg²⁺-ATPase activity and there was an increasing trend in the activity of Na⁺/K⁺-ATPase. In vitro, Coptidis Rhizoma protected erythrocytes from 2,2-azo-bis (2-amidinopropane) dihydrochloride-induced hemolysis in a dose-dependent manner at concentrations of 0.25-1.5 mg/ml, and also significantly inhibited the 2,2-azo-bis (2-amidinopropane) dihydrochloride-induced morphological alterations in mice erythrocytes. These results demonstrate that Coptidis Rhizoma is capable of protecting erythrocytes against oxidative damage probably by acting as an antioxidant and maintaining membrane integrity.

Aspirin and aspirin-like drugs induce HLA-DR expression in HT29 colon cancer cells

Nonsteroidal anti-inflammatory drugs (NSAIDs) decrease the incidence of colon cancer. The underexpression of HLA antigens during colon cancer development is suspected to be a mechanism by which malignant cells escape immune surveillance. We examined whether NSAIDs affect the expression of HLA-DR in HT29 human colon adenocarcinoma cells, which do not express HLA-DR. Aspirin, indomethacin and sulindac induced several-fold the expression of HLA-DR in these cells in a concentration- and time-dependent manner. Aspirin increased HLA-DR alpha steady-state mRNA levels and HLA-DR alpha gene transcription rate. These findings raise the possibility that such a mechanism may be operative in vivo.

Partial longitudinal resection of the anorectum and sphincter for very low rectal adenocarcinoma: a surgical approach to avoid permanent colostomy

AIM

Abdominoperineal resection has been the standard procedure for low rectal cancer. The present study details a new technique, partial longitudinal resection of the anorectum and sphincter, and assesses the oncological and functional outcomes.

METHOD

Between January 2004 and April 2008, 12 patients underwent partial longitudinal resection of the anorectum and sphincter for low rectal cancer. All patients underwent a diverting ileostomy and received biofeedback training before stoma closure. Functional results were assessed by vector manometry, Wexner constipation score and Wexner incontinence score. The quality of life (QoL) was assessed using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ-C30).

RESULTS

There was no postoperative mortality and a R0 curative resection was confirmed in every case. Morbidity included anastomotic leakage in three patients, one of whom underwent reoperation, and stenosis in 11, which was successfully managed with dilatation. The patient who underwent reoperation was not included in the functional analysis. The 11 successful patients received biofeedback training for 1-4 months, and underwent ileostomy closure 6-12 months after surgery. No patient had severe faecal incontinence after stoma closure. The EORTC QLQ-C30 global health status and QoL scores at 12 months after stoma closure were 50.4 ± 24.3, similar to preoperation scores of 52.3 ± 25.6 (P = 0.927), and not significantly different to scores for the healthy control population of 63.4 ± 23.5 (P = 0.539). No patients developed local recurrence during the median observation period (35.5 months). One patient had distant metastases at 24 months, and underwent resection of the left liver.

CONCLUSION

Curability and acceptable anal function can be obtained by partial longitudinal resection of the anorectum and sphincter in patients with very low rectal cancers. This technique is recommended as an alternative to abdominoperineal resection in patients with external sphincter muscle invasion or tumours located below the dentate line.