Structural and optical characterization of CdS films grown by photochemical deposition

CdS thin films are grown by photochemical deposition from an aqueous solution and characterized by x-ray diffraction (XRD), Raman spectroscopy, photoluminescence measurement, and optical transmission spectroscopy. The films are deposited at room temperature and annealed at temperatures up to 500°C. The as-deposited film is dominantly zinc blende cubic. The cubic phase remains dominant until the annealing temperature becomes higher than 400°C. By the annealing at 450°C, the XRD pattern turns to that of hexagonal phase. Moreover, its peak width decreases and the near-band-edge luminescence begins to be observed. The band gap is decreased by annealing below 400°C and then abruptly increased by the annealing at 450°C. This annealing behavior of the band gap is interpreted considering the quantum size effects, the band tail due to disorder, and the cubic-hexagonal transition.application/pdfjournal articl

Slow photoconductivity decay in 3C-SiC on Si substrates

N-type 3C-SiC layers grown on p-type (001) Si substrates were characterized by the conventional photoconductivity decay method. A N2 laser (337 nm wavelength) was used as the excitation source. A very slow component with a time constant larger than 1 ms was observed in the photoconductivity decay curves. A numerical simulation considering a trap with a very small capture cross section for electrons (<1×10-21 cm2) was able to reproduce main qualitative features of the experimental results. From comparison of the experimental decay curves with the theoretical ones, the following conclusions were drawn about the trap in 3C-SiC. (1) The trap level Et is close to the conduction band edge Ec(Ec-Et = 0.1-0.15eV). (2) The concentration is considered to decrease with increasing donor concentration.application/pdfjournal articl

Image-guided core needle biopsy for musculoskeletal lesions

Background: Image-guided percutaneous core needle biopsy (CNB) has been an important diagnostic procedure for musculoskeletal lesions. Here we surveyed the variety of diagnostic strategies available and assessed the clinical usefulness and limitations of image-guided CNB carried out by a multidisciplinary team comprising specialists in various fields. Methods: We conducted a retrospective study of 284 image-guided CNBs among 1899 consecutive biopsy procedures carried out at our institution for musculoskeletal tumorous conditions, focusing on their effectiveness including diagnostic accuracy and utility for classification of specimens according to malignant potential and histological subtype as well as their correlation with biopsy routes. Results: Among the 284 studied biopsies, 252 (88.7%) were considered clinically “effective”. The sensitivity for detection of malignancy was 94.0% (110/117) and the specificity was 95.3% (41/43). The diagnostic accuracy for detection of malignancy was 94.4% (151/160) and that for histological subtype was 92.3% (48/52). The clinical effectiveness of the procedure was correlated with the complexity of the biopsy route (P = 0.015); the trans-pedicular, trans-retroperitoneal and trans-sciatic foramen approaches tended to yield ineffective results. Repeat biopsy did not have a significant impact on the effectiveness of image-guided CNB (P = 0.536). Conclusions: The diagnostic accuracy rates of image-guided CNB performed at multidisciplinary sarcoma units were usable even for patients who have variety of diagnostic biopsy procedures. It is important to establish and implement diagnostic strategies based on an understanding that complicated routes, especially for spine and pelvic lesions, may be associated with ineffectiveness and/or complications

Giant cell tumor of bone arising in long bones possibly originates from the metaphyseal region

Giant cell tumor of bone (GCTB) is a primary benign bone tumor with a locally aggressive character. Definitive descriptions of the site of origin for this type of tumor are not available. The aim of the present study was to evaluate the site of origin of GCTB of long bones with regards to epiphyseal lines by means of radiographic examination. For that purpose, plain X‑ray scans of 71 GCTBs arising in long bones were retrospectively reviewed. The tumor locations were the distal femur in 31 cases, proximal femur in 11 cases, proximal tibia in 13 cases, distal radius in 6 cases, proximal humerus in 5 cases and proximal fibula in 5 cases. The vertical center (VC) of the tumor was determined with X‑ray anteroposterior view, and the correlation between the VC and the epiphyseal line, and between the distance from the epiphyseal line to the VC and tumor area or volume were analyzed using a regression model equation based on scatter plot diagrams. The VC of the tumor was located in the metaphyseal region in 57 cases, in the epiphyseal line in 11 cases and in the epiphyseal region in 3 cases. In cases of GCTB located in the distal femur or proximal tibia, significant correlations between the distance from the VC to the epiphyseal line and tumor area or volume were identified. The site of origin of GCTB was estimated to be located in the metaphyseal region. GCTB often occurs in mature patients, which renders it challenging to estimate the true site of origin of this lesion, since the metaphyseal line has disappeared in mature patients. The results of the present study suggest that GCTB possibly originates in the metaphyseal region.journal articl

Clinical implications of using both fluoropyrimidine and paclitaxel in patients with severe peritoneal metastasis of gastric cancer: A post hoc study of JCOG1108/WJOG7312G

Background: In the JCOG1108/WJOG7312G trial, a combination (FLTAX) of 5-fluorouracil (FU) /leucovorin (FL) and paclitaxel (PTX) did not show superiority in overall survival (OS) to FL in untreated patients with severe peritoneal metastasis of gastric cancer (GC-SPM), some of whom received second-line chemotherapy with PTX after FL. This post hoc study aimed to investigate the clinical implications of using both FU and PTX either sequentially or in combination for patients with GC-SPM.Methods: A total of 94 patients were enrolled and categorized into the following three subgroups: patients treated with (1) FL followed by PTX (FL/PTX, = 25), (2) FL followed by best supportive care (BSC) (FL/BSC, = 21), and (3) FLTAX ( = 48). OS was compared between the subgroups. By comparing baseline factors between the FL/PTX and FL/BSC subgroups, factors preventing the sequential use of PTX (SUP) were explored using logistic regression model. The efficacy of FL and FLTAX was compared according to the presence of risk factors preventing SUP.Results: The FL/PTX subgroup showed better and equivalent OS compared to the FL/BSC (median 7.8 vs. 2.0 months, < 0.01) and FLTAX (median 7.8 vs. 8.0, = 0.49) subgroups, respectively. Glasgow Prognostic Score 2 and initially unresectable disease were identified as risk factors preventing SUP. Absence of both risks predicted SUP with a sensitivity of 13% and a specificity of 100%, whereas absence of any risks predicted SUP with a sensitivity of 67% and a specificity of 62%. FLTAX showed better OS than FL in patients with one or two of these risks but worse OS in those with none.Conclusions: Although sequential use of FU and PTX showed equivalent survival to FLTAX in patients with GC-SPM, FLTAX might be preferable given the difficulty in selecting patients likely to receive sequential use at the initiation of first-line chemotherapy

Clinical factors affecting pathological fracture and healing of unicameral bone cysts

BACKGROUND: Unicameral bone cyst (UBC) is the most common benign lytic bone lesion seen in children. The aim of this study is to investigate clinical factors affecting pathological fracture and healing of UBC. METHODS: We retrospectively reviewed 155 UBC patients who consulted Nagoya musculoskeletal oncology group hospitals in Japan. Sixty of the 155 patients had pathological fracture at presentation. Of 141 patients with follow-up periods exceeding 6 months, 77 were followed conservatively and 64 treated by surgery. RESULTS: The fracture risk was significantly higher in the humerus than other bones. In multivariate analysis, ballooning of bone, cyst in long bone, male sex, thin cortical thickness and multilocular cyst were significant adverse prognostic factors for pathological fractures at presentation. The healing rates were 30% and 83% with observation and surgery, respectively. Multivariate analysis revealed that fracture at presentation and history of biopsy were good prognostic factors for healing of UBC in patients under observation. CONCLUSION: The present results suggest that mechanical disruption of UBC such as fracture and biopsy promotes healing, and thus watchful waiting is indicated in these patients, whereas patients with poor prognostic factors for fractures should be considered for surgery

Analysis of the MYD88 L265P mutation in IgM monoclonal gammopathy by semi-nested polymerase chain reaction-based restriction fragment length polymorphism method

MYD88 L265P mutation causes constitutive activation of NF-κB and possible driver mutation in B-cell lymphoid malignancies. It is frequently detected in Waldenstrom’s macroglobulinemia （WM） （50％-100％）, and its detection is important in diagnostic and therapeutic targets of this syndrome. Standard detection method of MYD88 L265P mutation in clinical practice has yet to be established. We developed semi-nested PCR-based restriction fragment length polymorphism （snPCR-RFLP） to detect the mutation. The snPCR-RFLP method is a modification of the PCR-RFLP method, which uses the restriction enzyme BsiEI that recognizes CGACT/CG, intending to increase detection sensitivity by amplification of mutated allele in the DNA sample using semi-nested PCR before enzyme digestion. The detection sensitivity of snPCR-RFLP was estimated as 0.1％, by detecting mutated allele in wild-type allele in the cloned plasmid DNA, which is comparable with allele-specific （AS） PCR method widely used as sensitive detection method. By analyzing 40 cases with IgM monoclonal gammopathy, snPCR-RFLP detected 29/40 （70％） of all cases, 22/31 （70.9％） of WM, and 6/9 （66.6%） of IgM-type monoclonal gammopathy with undetermined significance （IgMMGUS）, including five cases （three cases of WM and two cases of IgMMGUS） in which the mutation was detected only by snPCR-RFLP but not by Sanger sequencing method. Regarding DNA sample status, particularly five cases, a case was extracted from formalin-fixed paraffin-embedded tissue and four cases were extracted from cells by Ficoll-Hypaque density gradient. In correlation with clinical features, the MYD88 mutation detected by snPCR-RFLP method was associated with the adverse prognostic index （WMIPSS） of WM using patient age, hemoglobin （Hb） level, platelet count, β2MG level, and serum IgM level （p＝0.055）. The snPCR-RFLP method is a clinically useful MYD88 mutation detection method that can be performed in general laboratories