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To investigate the effects of the optical field and the Fermi velocity on the transport properties of spin and valley electrons, we impose a normal/ferromagnetic/normal (N/F/N) quantum structure based on the monolayer WSe 2. The results indicate that there is a strong switch effect for spin- and valley-related electrons. When left-handed off-resonant circularly polarized light is irradiated in the intermediate ferromagnetic region, 100 % polarization for K valley electrons can be achieved in the entire effective energy spectrum of the optical field. Meanwhile, 100 % polarization of the K ′ valley can also be gained with the right-handed off-resonant circularly polarized light in the junction. Moreover, the perfect polarization of spin-up electrons can be obtained when the ferromagnetic exchange field is applied to the structure. Additionally, the Fermi velocity barrier also changes the energy band of the studied material, which makes the spin and valley transport increase with the increase of the velocity barrier but does not produce spin or valley polarizations. These interesting results clarify that the optical field and the Fermi velocity both make a contribution to the modulation of spin electrons for the two valleys and provide a useful method for the design of novel spintronic and valleytronic devices. [ABSTRACT FROM AUTHOR]

Oncolytic adenoviruses (Ad) represent a promising therapeutic platform for the treatment of cancer. Despite their reliable safety and ease of handling, the recognized oncolytic Ad immune responses, biodistribution, spreads and efficacy of viral replication, compared with non-replicating adenoviruses, in vivo, have not been well understood. The present study establishes a novel permissive mouse immunocompetent orthotopic colon carcinoma model focusing on non-replicating Adv-TKs, a well-established adjuvant treatment in cancer and comparing its antitumor efficacy and safety profile with those of the two newly synthesized oncolytic Ad vectors, M7 and M8, formed by the insertion of a fragment of HSV-TK cDNA into the deleted 6.7 K/gp19 K or ADP in the E3 region to the E1A CR2-deleted Ad5 vectors. Systemic administration in the permissive immunocompetent orthotopic colon carcinoma mouse model, which could better predict the clinical results of Ad-based treatment by combining the characteristics that fully mimic the clinical orthotopic carcinogenesis and permissive Ad replication, show M7 and M8, especially M8, to have more powerful antitumoral efficacy and similar safety profiles relative to the Adv-TK. This promises a significant advance in the field of Ad cancer therapy and will perhaps provide the impetus to design new preclinical M7 and M8 viruses in the future. [ABSTRACT FROM AUTHOR]

Malignant peripheral nerve sheath tumours (MPNST) are rare soft tissue sarcomas. The aim of this study was to assess clinicopathological characteristics and prognostic factors in order to improve the treatment of such tumours in the head and neck region. We performed a retrospective analysis of head and neck MPNST patients in our hospital between 1996 and 2012. Clinical features and pathological findings of these cases (n=43) were summarized. In addition, prognostic variables were evaluated by univariate and multivariate analyses. The median age of the patients at presentation was 41 years. Surgery was the main treatment approach. Pertinent information regarding the presence of neurofibromatosis type 1 was found in 13 patients (30.2%). Two-thirds of these patients were admitted for a primary tumour (n=27, 62.8%), while one-third (n=16, 37.2%) were treated for recurrent neoplasms. The overall survival rate was 46.5%. Multivariable analysis identified tumour size, surgical margins, and postoperative radiotherapy to be independent prognostic factors. MPNST of the head and neck is extremely difficult to manage. Surgery with postoperative radiation may be the optimum choice of treatment for primary head and neck MPNST. [ABSTRACT FROM AUTHOR]

Mammalian checkpoint kinases 1 and 2 (Chk1 and Chk2) are essential kinases that are involved in cell cycle checkpoint control, and the abrogation of either has been proposed as one way to sensitize cancer cells to DNA-damaging agents. However, it remains unclear which kinase is the most therapeutically relevant target, and whether multiple kinases might need to be targeted to achieve the best efficacy because of their overlapping substrate spectra and redundant functions. To clarify this issue, we established asynchronous cell cycle arrest models to investigate the therapeutic outcomes of silencing Chk1 and Chk2 in the presence of irradiation or cisplatin. Our results showed that Chk1- and Chk2-targeting small interference RNAs (siRNAs) demonstrated synergistic effects when both siRNAs were used simultaneously. Interestingly, Chk1 and Chk2 co-expression occurred in ∼90% of neoplastic tissues examined and showed no difference in neoplastic versus non-neoplastic tissues. Therefore, the selective targeting of Chk1 and Chk2 by oncolytic adenovirus mutants was chosen to treat resistant tumor xenograft mice, and the maximum antitumoral efficacy was achieved with the combined co-abrogation of Chk1 and Chk2 in the presence of low-dose cisplatin. This work deepens our understanding of novel strategies that target checkpoint pathways and contributes to the development of novel, potent and safe checkpoint abrogators. [ABSTRACT FROM AUTHOR]

We investigate the control of 0-Π transition in Josephson junctions consisting of a highly spin-polarized ferromagnet coupled to two iron pnictide superconductors (SCs). It is shown that, a 0-Π transition as a function of interband coupling strength is always exhibited, which can be experimentally used to discriminate the s± -wave pairing symmetry in the iron pnictide SCs from the s++ -wave one in MgB2. By tuning the doping level in the s± -wave SCs, one can vary the interband coupling strength so as to obtain the controllable 0-Π transition. This device may be realized with current technologies and has practical use in Cooper pair spintronics and quantum information. [ABSTRACT FROM AUTHOR]

The integration of an approximate model and a clonal selection algorithm (CSA) is considered as one of the most effective ways to solve complex optimization design problems in engineering. In this study, first, a process for developing an approximate model and the principles of clonal selection algorithms is presented. Second, a variotherm temperature injection mold was used to produce a large liquid crystal display (LCD) TV panel. Next, an approximate model for optimizing the layout of the heating channels in the mold was established. Third, the clonal selection algorithm program was coded according to the aforementioned principles to solve the established approximate model. Finally, the layout of the heating channels was optimized and the optimal solutions were obtained. Finite element simulation and industrial injection production indicated that the integration of the approximate model and clone selection algorithm used in this study to optimize the layout of the heating channels for the injection mold was very effective. [ABSTRACT FROM AUTHOR]

Owing to rarity and awareness deficiency towards inflammatory myofibroblastic tumor (IMT), we sought to review on its clinicopathological features; arising awareness to achieve early diagnosis; exploring prognostic factors and then establishing a treatment protocol. Retrospective study was performed on patients with histological proven IMT between January 2003 and December 2010. Their demographic data, clinical and histological presentations were recorded. Overall survival (OS) and progression-free-survival (PFS) were estimated via Kaplan-Meier method. Cox regression model was applied to determine the significant of prognostic factors. Logistic regression model was established to predict the probability of relapse. A total of 28 patients. Five-year PFS was 65%. Surgical margins primarily and independently determined the survival, followed by size, pseudocapsule of the lesion, intra-lesional necrosis and lastly Ki-67 and ALK overexpression. Logistic model in prediction of relapse was established, with the formula as probability of relapse=1/(1+e(-)(z)) where e=exponential function, z=constant value (3.9)+B*margin+B*size+B*immunohistochemical expression+B*pseudocapsule+B*intra-lesional necrosis. Immunohistochemical overexpression was significant if Ki-67 was strongly expressed with a conditioned ALK overexpression simultaneously. Staining intensity must be at least moderate for those ALK nuclear staining was less than 25%. Weak ALK staining intensity is only significant if nuclear staining was more than 25%. Diagnosis of IMT is achieved via exclusion. Radical resection and obtaining negative margins remains the mainstay of treatment. Both high and moderate-risk groups required post-operative radiotherapy. In low-risk group, post-operative radiotherapy was recommended if the lesion is larger than 5cm in diameter with a conditioned ALK & Ki-67 overexpression. [ABSTRACT FROM AUTHOR]

Abstract: Er2O3 films were grown on Ge (001) substrates at different temperatures by molecular beam epitaxy using metallic Er and molecular oxygen sources with otherwise identical conditions. High-resolution transmission electron microscopy and X-ray photoelectron spectroscopy were used to characterize the microstructures and compositions of the films. The film deposited at room temperature is found to be composed of an Er2O3 layer and an ErGexOy interface layer with a thickness of 5.5nm; the film grown at 300°C has a mixed structure of Er2O3 and ErGexOy and the thickness was found to be reduced to 2.2nm; the film grown at 450°C becomes much rougher with voids formed underneath the film, having a mixed structure of three compounds of Er2O3, GeO and ErGexOy. The growth mechanisms of the films at different temperatures are suggested. Current images obtained by tunneling atomic force microscopy show that the film grown at 450°C has much more leaky spots than those grown at RT and 300°C, which may arise from the formation of volatile GeO in the film. [Copyright &y& Elsevier]

BACKGROUND AND PURPOSE Emodin (1,3,8-trihydroxy-6-methylanthraquinone) is an active component of many herb-based laxatives. However, its mechanism of action is unclear. The aim of the present study was to investigate the role of mast cells and enteric neurons in emodin-induced ion secretion in the rat colon. EXPERIMENTAL APPROACH Short-circuit current ( ISC) recording was used to measure epithelial ion transport. A scanning ion-selective electrode technique was used to directly measure Cl- flux ( JCl−) across the epithelium. RIA was used to measure emodin-induced histamine release. KEY RESULTS Basolateral addition of emodin induced a concentration-dependent increase in ISC in colonic mucosa/submucosa preparations, EC50 75 µM. The effect of emodin was blocked by apically applied glibenclamide, a Cl- channel blocker, and by basolateral application of bumetanide, an inhibitor of the Na+-K+-2Cl- cotransporter. Emodin-evoked JCl− in mucosa/submucosa preparations was measured by scanning ion-selective electrode technique, which correlated to the increase in ISC and was significantly suppressed by glibenclamide and bumetanide. Pretreatment with tetrodotoxin and the muscarinic receptor antagonist atropine had no effect on emodin-induced Δ ISC in mucosa-only preparations, but significantly reduced emodin-induced Δ ISC and JCl− in mucosa/submucosa preparations. The COX inhibitor indomethacin, the mast cell stabilizer ketotifen and H1 receptor antagonist pyrilamine significantly reduced emodin-induced Δ ISC in mucosa and mucosa/submucosa preparations. The H2 receptor antagonist cimetidine inhibited emodin-induced Δ ISC and JCl− only in the mucosa/submucosa preparations. Furthermore, emodin increased histamine release from the colonic mucosa/submucosa tissues. CONCLUSIONS AND IMPLICATIONS The results suggest that emodin-induced colonic Cl- secretion involves mast cell degranulation and activation of cholinergic and non-cholinergic submucosal neurons. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of the study was to develop a surgical classification system for primary malignant sacral tumors.Methods: The sacrum is divided into three regions 1, 2 and 3 by the S1-S2 and S2-S3 junctions. En bloc resections were classified into five types: type I involves regions 1, or 1 and 2, or regions 1, 2 and 3, type II involves regions 2 and 3, and type III involves only region 3. Type IV includes sagittal hemisacrectomy and resection of a portion of the adjacent ilium. Type V includes the sacrum and the fifth lumbar vertebra. 117 patient cases (68 females and 49 males) were reviewed.Results: There were two perioperative deaths. Of the 35 patients who should have undergone type I resection, local recurrence (LR) occurred in four of the 14 patients who underwent type I resection with free margins without tumor rupture. The other 21 patients underwent piecemeal resection, and LR occurred in 15 (P = 0.013). 35 patients underwent type II resection. Free margin without tumor rupture was accomplished in 26 and LR occurred in 6. Tumor rupture (TR) occurred in the other 9 and LR occurred in seven (Yates' P = 0.012). All 33 patients underwent type III resection with free margins without tumor rupture. LR occurred in five. 11 patients had type IV resection. Free margin without tumor rupture was accomplished in seven and LR occurred in three. TR occurred in the other four, and LR occurred in two (Yates' P = 0.689). One patient underwent type V resection with free margin without tumor rupture and LR occurred. Postoperatively, less than 1/3 needed long-term urethral catheterization. No patients received colostomy for postoperative fecal incontinence. All the patients were able to ambulate.Conclusion: Our classification system and the corresponding surgical approaches are helpful in dealing with primary malignant sacral tumors. Better oncologic results could be expected if free margin without tumor rupture was accomplished. [ABSTRACT FROM AUTHOR]

Recently, we demonstrated the expression of NKCC2, an absorptive isoform of NKCC specifically expressed in the kidney, in the rat gastrointestinal tract including the distal colonic mucosa. This study aims to investigate its localization in colonic epithelia and possible role in the colonic ion transport. Reverse transcription polymerase chain reaction (RT-PCR), Western blotting, and immunohistochemistry were used to investigate the expression and localization of NKCC2. The role of NKCC2 on the colonic ion transport was examined by mean of short-circuit current (I(SC)) monitoring. The results indicated that NKCC2 was expressed in the apical region of the epithelia in rat distal colon and human sigmoid colon. NKCC1, which is a secretive NKCC isoform, was localized predominantly in the basolateral membrane, which has been well documented. Serosal (basolateral) administration of bumetanide, an inhibitor of both NKCC1 and NKCC2, inhibited serosal forskolin-induced I(SC) increase by 66% but enhanced the luminal (apical) forskolin-induced I(SC) response by 63%. Furthermore, the blocking of epithelial Na(+) channels by apical addition of amiloride (10 [mu]mol/L), K(+) channels by tetraethylammoniumion (TEA) (5 mmol/L), or glibenclimide (0.1 mmol/L) did not affect apical forskolin-induced I(SC) increase, excluding the involvement of cations, Na(+) and K(+), in the I(SC) response. The luminal forskolin-induced I(SC) increase was enhanced markedly by the apical pretreatment with bumetanide or the reduction of apical Cl(-) concentration by 114% and 198%, respectively, which were inhibited by apical addition of glibenclimide (1 mmol/L) by more than 60%. This finding suggests the involvement of an anion. Furthermore, the removal of basolateral HCO(3)(-) reduced apical forskolin-induced I(SC) by more than 75% indicated that the apical forskolin-induced I(SC) increase in rat distal colon was mediated by Cl(-) absorption and HCO(3)(-) secretion. In conclusion, NKCC2 is expressed widely in the colonic epithelium in rat distal colon and human sigmoid colon, especially in the apical membrane. It involves the process of colonic Cl(-) absorption coupled with HCO(3)(-) secretion. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Accessory parotid lesions are clinically rare and its management remains poorly understood. The aim of this study was to analyze the clinical management of accessory parotid lesions. STUDY DESIGN: From April 1999 to November 2008, a retrospective analysis of 32 patients with accessory parotid lesions was performed. The preoperative examinations, surgical treatment, and prognosis were recorded and analyzed. RESULTS: Among the 32 patients, there were 8 men and 24 women with an overall average age of 45 years. These patients always presented without obvious symptoms, and the masses were moderate to hard in hardness without tenderness, mobile, and with clear boundary. The pathologic diagnoses were 24 benign and 8 malignant lesions. Surgery and surgery plus radiotherapy were performed in the patients with benign and malignant lesions, respectively, with good prognosis. CONCLUSIONS: Accessory parotid lesions are rare, and the clinical manifestation is always the same for benign tumors. Surgical resection and surgical resection plus radiotherapy are the primary choices of treatment for benign and malignant lesions, respectively. The prognosis is always good. [ABSTRACT FROM AUTHOR]

To retrospectively review the diagnosis and treatment outcomes of 21 diagnosed with synovial sarcoma (SS) extending to skull base region and identify prognostic factors for local recurrence and distant metastasis. The clinical and pathological records of 21 synovial sarcoma cases involving skull base treated at Department of Oral and Maxillofacial Surgery, Affiliated to Ninth People's Hospital, Shanghai Jiao Tong University, from 2003 to 2008 were reviewed. Parameters including clinical, radiographic, histological findings, and treatment modalities were analyzed. Prognostic factors influencing overall survival, local recurrence, and metastasis were identified. Categorical variables were compared between groups for local recurrence and distant metastasis by using 2-tailed Fisher exact test. The sample consisted of 8 males and 13 females with a median age of 23. 42.9% of cases showed skull base bone erosion with 9.5% of cases presenting intracranial tumor extension. 52.4% of cases died from recurrence or metastasis with a median survival time of 11months. Orbital involvement, perineural and cranial invasion along with other factors were statistically significant for their impact on overall survival. Local recurrence was associated with tumors located in the infratemporal space (p=0.01), perineural invasion (p=0.001), pathological grade 3 (p=0.005), and tumor size >5cm (p=0.008). The aggressive behavior of skull base SS and its close proximity to vital structures make the diagnosis and management a challenge. The study reported high local recurrence rates despite surgical and postoperative radiotherapy. Adjuvant chemotherapy did not seem to affect distant metastasis rates. [ABSTRACT FROM AUTHOR]

Abstract: Ultrathin single crystalline Tm2O3 films have been grown on Si (001) substrate by molecular beam epitaxy using metallic Tm source at a substrate temperature of 600°C and an atomic oxygen ambient pressure of 2×10−7 Torr. The epitaxial relationship between the Tm2O3 films and the Si substrates is Tm2O3 (110)//Si (001), Tm2O3 [001]//Si [110] or Tm2O3 [1−10]//Si [110]. Higher oxygen pressure would change the preferential growth orientations from (110) to (111) with the growth mode from epitaxy to non-epitaxy. After annealing in O2 ambience at 450°C for 30min, the single crystalline films exhibit a dielectric constant of 10.8 and a leakage current density of 2×10−3 A/cm2 at an electric field of 1MVcm−1 with an equivalent oxide thickness of 2.3nm. Small angle X-ray reflectivity measurements were carried out to investigate the annealing effect in the improvement of electrical properties of the films. [Copyright &y& Elsevier]

Background and purpose: 5-Hydroxytryptamine (5-HT) is a key regulator of the gastrointestinal system and we have shown that submucosal neuronal 5-HT3 receptors exerted a novel inhibitory effect on colonic ion transport. The aim of the present study was to investigate the precise mechanism(s) underlying this inhibitory effect. Experimental approach: Mucosa/submucosa or mucosa-only preparations from rat distal colon were mounted in Ussing chambers for measurement of short-circuit current ( Isc) as an indicator of ion secretion. Somatostatin release was determined with radioimmunoassay. Intracellular cAMP content was measured with enzyme-linked immunoadsorbent assay ( elisa). Immunohistochemical techniques were used to study the expression of 5-HT3 receptors, somatostatin and somatostatin receptors in colonic tissue. Key results: In rat distal colonic mucosa/submucosa preparations, pretreatment with 5-HT3 receptor antagonists enhanced 5-HT-induced increases in Isc. However, in mucosa-only preparations without retained neural elements, pretreatment with 5-HT3 receptor antagonists inhibited 5-HT-induced Δ Isc. Pretreatment with a somatostatin-2 (sst2) receptor antagonist in mucosa/submucosa preparations augmented 5-HT-induced Δ Isc. Combination of sst2 and 5-HT3 receptor antagonists did not cause further enhancement of 5-HT-induced Δ Isc. Moreover, both sst2 and 5-HT3 receptor antagonists enhanced 5-HT-induced increase in intracellular cAMP concentration in the mucosa/submucosa preparations. 5-HT released somatostatin from rat colonic mucosa/submucosa preparations, an effect prevented by pretreatment with 5-HT3 receptor antagonists. Immunohistochemical staining demonstrated the presence of 5-HT3 receptors on submucosal somatostatin neurons and of sst2 receptors on colonic mucosa. Conclusion and implications: Activation of neuronal 5-HT3 receptors in the submucosal plexus of rat colon suppressed 5-HT-induced ion secretion by releasing somatostatin from submucosal neurons. [ABSTRACT FROM AUTHOR]