Study on the Low Temperature Photoluminescence Spectra of II-VI Group Telluride Bulk Crystals.

The dominant point defects in II-VI group telluride bulk crystals grown from melt usually varied due to different growth conditions and cooling history, in turn affect the electrical and optical behaviors of corresponding single crystals and devices. Low temperature photoluminescence (PL) spectra acts as a contact-less and non-destructive technique, can be used to evaluate the behaviors of point defects and impurities in the as-grown telluride bulk crystals. With the purpose of comparing the defect structures in un-doped ZnTe and CdTe crystals grown under Te-rich condition, 8. 6 K PL spectra were obtained. The conductivity type and resistivity were investigated by Hall-effect measurements at room temperature (RT). For p-type low resistivity ZnTe crystal, the intensity of. free electron to neutral acceptor (e, A(0)) transition is higher than the donor-acceptor pair (DAP) transition, which predominates in the PL spectra. However, in the contrary, DAP peak dominates the PL emissions for n-type high resistivity CdTe. This difference is mainly attributed to the distinct properties of the grown-in point defects due to different growth. velocities and cooling processes. In terms of the un-doped CdZnTe crystal grown under stoichiometry, neutral donor bound exciton (D(0), X) emission is predominated in the 9.2 K PL spectra, with the intensity of (e, A(0)) peak is higher than DAP peak, which then overlaps to each other when the temperature higher then 15 K. In the case of In-doped CdZnTe crystal grown by Te-rich situation, A-center emission is clearly observed, which introduces an energy level approximately of 0.15 eV, with the intensity proportional to the concentration of indium dopant. This defect is seemingly related to the complex of [In(Cd)+V(Cd)2-]- formed by a shallow donor In(Cd) and Cd vacancy.

[Expression and Clinical Significance of Eukaryotic Initiation Factor 4E in Newly Diagnosed Patients with Multiple Myeloma].

OBJECTIVE: To explore the expression and clinical significance of eukaryotic translation initiation factor 4E(eIF4E) in bone marrow samples of newly diagnosed multiple myeloma (NDMM) patients. METHODS: Immunohistochemical staining was used to analyze the expression of eIF4E protein in bone marrow biopsy samples from 75 NDMM patients and 25 patients with benign bone marrow disease. Clinical data were collected to analyze the correlation between eIF4E protein expression and clinical features and its prognostic significance in bone marrow samples of NDMM patients. RESULTS: The positive rate of eIF4E protein expression in bone marrow samples of NDMM patients was higher than that in patients with benign bone marrow disease (P<0.001). Positive expression of eIF4E protein was correlated with elevated serum lactate dehydrogenase in MM patients. Univariate and multivariate analysis showed that positive expression of eIF4E protein was significantly associated with shortened overall survival (OS) in NDMM patients, and was an independent risk factor affecting OS in NDMM patients. CONCLUSION: Positive expression of eIF4E protein is an independent poor prognostic factor for OS in NDMM patients.

[Peripheral primitive neuroectodermal tumor of trachea: a case report and review of literatures].

OBJECTIVE: To improve the understanding of tracheal peripheral primitive neuroectodermal tumor (PNET). METHODS: A case of tracheal PNET diagnosed in July 2010 was reported and the related literatures were reviewed. The literature review was carried out respectively with "primitive neuroectodermal tumor", "peripheral" as the search terms in Wanfang med online and PubMed database by September 2011. RESULTS: A case of 63 year-old female patient, who had been misdiagnosed as having chronic pharyngitis, chronic bronchitis and bronchial asthma, was admitted to the hospital because of cough and sputum production for 50 days, and anhelation for 1 month. After admission, the chest computerized tomography showed a space-occupying lesion in the middle of the trachea. Bronchoscopy showed a pedicle neoplasm 4 cm under the subglottic, with integral capsule, smooth surface and rich vascellum. Subsequently, tumor resection under bronchoscope was performed. Pathology report after operation showed infiltration of flake small round malignant cells under bronchial mucosa. Immunohistochemistry showed CD(99)(+), Syn(+) and S-100(+). EWS-FLI-1 fusion transcript was detected by RT-PCR. Accordingly, it was diagnosed as PNET. The symptoms of cough and anhelation were disappeared after operation. So far, there was no local recurrence and distant metastasis with 14 months follow-up. A total of 111 literatures were received in Pubmed, including one of prospective study, one of review, 22 of retrospective study and 87 of case report. Forty literatures and 187 cases in all were received in Wanfang Med Online, including 24 of retrospective study and 16 of case report. But, there were no reports about tracheal PNET. CONCLUSIONS: PNET can occur in the trachea and is easy to be misdiagnosed. To make a definite diagnosis, histopathology and immunohistochemistry are needed and detection of EWS-FLI-1 fusion transcript is a reliable marker for molecular diagnosis. The tracheal pPNET may be different with the pPNETs in other parts, and has a lower-grade invasion and less distant metastasis.

[Expression of MicroRNA-26a and Its Target Gene CDK6 in Extra-nodal NK/T-Cell Lymphoma].

OBJECTIVE: To explore the expression level of microRNA-26a and its target gene CDK6 in extranodal NK/T-cell lymphoma (ENKTCL) and their possible role in genesis and development of ENKTCL. METHODS: Real time fluorescent quantitative PCR was used to detect the expression level of miR-26a in tissue of 15 patients with ENKTCL and 10 samples of normal NK cells. Maxvision immunohistochemistry technique was used to detect the expression level of CDK6 and miR-26a in tissue of 20 ENKTCL cases, 10 cases of proliferative lymphadenitis and 10 samples of normal lymph node, respectively. The possible role of miR-26a and its target gene CDK6 in genesis and development of ENKTCL were analyzed according to the clinical features of ENKTCL patients. RESULTS: The expression of miR-26a was significantly lower in ENKTCL than that in normal NK cells. The expression of CDK6 was significantly higher in ENKTCL group than that in group proliferative lymphadenitis and normal lymph node. Correlation analysis showed that there was significant negative correlation between miR-26a expression and CDK6 expression (r = -0.54, P = 0.04). Meanwhile, there were no correlation of miR-26a expression with age, sex, Ann Arbor stage, LDH level, B symptoms and IPI. Although, there were no correlation of CDK6 expression with age, sex, LDH level and B symptoms, there were positive correlation of CDK6 expression with Ann Arbor stage and IPI. CONCLUSION: that abnormal expression of miR-26a may participate in genesis and development of ENKTCL through regulating the expression of its target gene CDK6.