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Aims: Alterations in microenvironments are a hallmark of cancer, and these alterations in germinomas are of particular significance. Germinoma, the most common subtype of central nervous system germ cell tumours, often exhibits massive immune cell infiltration intermingled with tumour cells. The role of these immune cells in germinoma, however, remains unknown. Methods: We investigated the cellular constituents of immune microenvironments and their clinical impacts on prognosis in 100 germinoma cases. Results: Patients with germinomas lower in tumour cell content (i.e. higher immune cell infiltration) had a significantly longer progression‐free survival time than those with higher tumour cell contents (P = 0.03). Transcriptome analyses and RNA in‐situ hybridization indicated that infiltrating immune cells comprised a wide variety of cell types, including lymphocytes and myelocyte‐lineage cells. High expression of CD4 was significantly associated with good prognosis, whereas elevated nitric oxide synthase 2 was associated with poor prognosis. PD1 (PDCD1) was expressed by immune cells present in most germinomas (93.8%), and PD‐L1 (CD274) expression was found in tumour cells in the majority of germinomas examined (73.5%). Conclusions: The collective data strongly suggest that infiltrating immune cells play an important role in predicting treatment response. Further investigation should lead to additional categorization of germinoma to safely reduce treatment intensity depending on tumour/immune cell balance and to develop possible future immunotherapies. [ABSTRACT FROM AUTHOR]

Melting-solidification transition of Zn nanoparticles (NPs) with the mean diameter of 11.5 nm, embedded in silica glass, was investigated by glancing incident x-ray diffraction (GIXRD) at high temperatures using synchrotron radiation (SR). With increasing temperature, 101Zn diffraction peak gradually decreases up to ∼360 °C and then steeply decreases. This is due to the melting of Zn NPs, which completes around 420 °C. With decreasing temperature, the solidification of the NPs begins around ∼310 °C. The temperature hysteresis with a width of ∼110 °C was observed. With temperature, the diffraction angle shows a shift without hysteresis, which is ascribed to thermal expansion of Zn NP lattice. Thermal expansion coefficient of Zn NPs was determined as 24.4×10-6 K-1 along the <101> direction. Optical absorption spectroscopy shows a broad ultraviolet (UV) peak which was observed at even higher temperatures than the melting temperature but shifts to the low-energy side with the melting. The energy shift in the UV peak also shows the temperature hysteresis which resembles with the melting-solidification hysteresis recorded by SR-GIXRD. The melting-solidification transition is also detectable by the optical absorption spectroscopy in the UV-visible-near-infrared region. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the interactions of implant diameter, insertion depth, and loading angle on stress/strain fields in a three-dimensional finite element implant/jawbone system and to determine the influence of the loading angle on stress/strain fields while varying the implant diameter and insertion depth. Materials and Methods: Four finite element models were created, which corresponded to two implant diameters and two insertion depths. The jawbone was composed of cortical and cancellous bone and modeled as a linearly elastic medium; the implant had a detailed screw structure and was modeled as an elastic-plastic medium. Static loading was applied to the coronal surface of the implant with a maximum load of 200 N for all the models. Loading directions were varied, with buccolingually applied loading angles ranging from 0 to 85 degrees. Results: Increases in the angle of force application caused not only increased maximum stress/strain values but worsened stress/strain distribution patterns in the bone and implant. The maximum stress in the bone always occurred at the upper edge of the cortical bone on the lingual side adjacent to the implant. The use of a larger-diameter implant or an increased insertion depth significantly reduced the maximum stress/strain values, improved the stress/strain distribution patterns and, in particular, decreased the stress/strain sensitivity to loading angle. Conclusions: A narrow-diameter implant, when inserted into jawbone with a shallow insertion depth and loaded with an oblique loading angle, is most unfavorable for stress distribution in both bone and implant. An optimized design of the neck region of an implant, in combination with a carefully controlled implant insertion depth that sets the threads of the implant neck well below the upper edge of the cortical bone, should be especially effective in improving the biomechanical environment for the maintenance of bone in implant/bone systems. [ABSTRACT FROM AUTHOR]

Chain elongation suppression of cyclic block copolymers in microphase-separated bulk was determined quantitatively. Solvent-cast and annealed films are confirmed to show alternating lamellar structure and their microdomain spacing D increases with increasing total molecular weight M according to the relationship D∝M0.59, which agrees quite consistently with the theoretically predicted power law, i.e., D∝M3/5. This result is in contrast to the well-established issue for linear block copolymers, where the relationship D∝M2/3 has been confirmed to hold both experimentally and theoretically. This means that chain elongation of each component block is suppressed considerably, owing to their looped conformation in strongly segregated bulk. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The initial nucleation of diamond film on a Si substrate, deposited by a three-step growth process together with a cycle bias enhanced nucleation (BEN) growth/H[sub 2] plasma etching technique in a microwave plasma enhanced chemical vapor deposition system has been investigated by atomic force microscopy, Raman spectroscopy and x-ray photoelectron spectroscopy. The surface morphology and the uniformity of {100}-oriented textured grains at the BEN step were found to be greatly increased by applying the cyclic process with some optimal H[sub 2] plasma etching time during the BEN stage. [ABSTRACT FROM AUTHOR]