Growth of bulk ß-Ga2O3 crystals from melt without precious-metal crucible by pulling from a cold container.

We report the growth of bulk ß-Ga2O3 crystals based on crystal pulling from a melt using a cold container without employing a precious-metal crucible. Our approach, named oxide crystal growth from cold crucible (OCCC), is a fusion between the skull-melting and Czochralski methods. The absence of an expensive precious-metal crucible makes this a cost-effective crystal growth method, which is a critical factor in the semiconductor industry. An original construction 0.4-0.5 MHz SiC MOSFET transistor generator with power up to 35 kW was used to successfully grow bulk ß-Ga2O3 crystals with diameters up to 46 mm. Also, an original diameter control system by generator frequency change was applied. In this preliminary study, the full width at half maximum of the X-ray rocking curve from the obtained ß-Ga2O3 crystals with diameters ≤ 46 mm was comparable to those of ß-Ga2O3 produced by edge-defined film fed growth. Moreover, as expected, the purity of the obtained crystals was high because only raw material-derived impurities were detected, and contamination from the process, such as insulation and noble metals, was below the detection limit. Our results indicate that the OCCC technique can be used to produce high-purity bulk ß-Ga2O3 single crystalline substrate.

Label-free photoacoustic imaging of human palmar vessels: a structural morphological analysis.

We analysed the vascular morphology of the palm using a photoacoustic tomography (PAT) instrument with a hemispherical detector array. The three-dimensional (3D) morphology of blood vessels was determined noninvasively. Overall, 12 females and 11 males were recruited as healthy volunteers. Their ages were distributed almost evenly from 22 to 59 years. In all cases, many vascular networks were observed just beneath the skin and were determined to be veins anatomically. To analyse the major arteries, the layer containing the subcutaneous venous network was removed from the image. The analysis focused on the common and proper palmar digital arteries. We used the curvature of these arteries as a parameter to analyse their morphologies. There was no significant difference in the curvature between genders when comparing the subjects as a whole. The blood vessel curvature increased with age. Good agreement was found between the 3D numerical analysis results and the subjective evaluation of the two-dimensional (2D) projection image. The PAT system enabled visualization of the 3D features of blood vessels in the palm and noninvasive analysis of arterial tortuousness.

Visualization of tumor-related blood vessels in human breast by photoacoustic imaging system with a hemispherical detector array.

Noninvasive measurement of the distribution and oxygenation state of hemoglobin (Hb) inside the tissue is strongly required to analyze the tumor-associated vasculatures. We developed a photoacoustic imaging (PAI) system with a hemispherical-shaped detector array (HDA). Here, we show that PAI system with HDA revealed finer vasculature, more detailed blood-vessel branching structures, and more detailed morphological vessel characteristics compared with MRI by the use of breast shape deformation of MRI to PAI and their fused image. Morphologically abnormal peritumoral blood vessel features, including centripetal photoacoustic signals and disruption or narrowing of vessel signals, were observed and intratumoral signals were detected by PAI in breast cancer tissues as a result of the clinical study of 22 malignant cases. Interestingly, it was also possible to analyze anticancer treatment-driven changes in vascular morphological features and function, such as improvement of intratumoral blood perfusion and relevant changes in intravascular hemoglobin saturation of oxygen. This clinical study indicated that PAI appears to be a promising tool for noninvasive analysis of human blood vessels and may contribute to improve cancer diagnosis.

ZEB1 induces EPB41L5 in the cancer mesenchymal program that drives ARF6-based invasion, metastasis and drug resistance.

Onset of the cancer mesenchymal program is closely associated with cancer malignancy and drug resistance. Among the different epithelial-mesenchymal transition (EMT)-associated transcriptional factors, ZEB1 has a key role in inducing the mesenchymal phenotypes and stem cell-like properties of different breast cancer cells. ARF6 and its effector AMAP1 are frequently overexpressed in breast cancer cells, and promote invasion, metastasis and drug resistance. EPB41L5 is induced during EMT, and mediates the disruption of E-cadherin-based cell-cell adhesion and the promotion of focal adhesion dynamics. Here we show that EPB41L5 is an integral component of the ARF6-based pathway, which is induced by ZEB1. We found that EPB41L5 is expressed at high levels in malignant breast cancer cells and binds to AMAP1. ZEB1 induced EPB41L5 both in cancer cells and normal cells. This relationship was recaptured with The Cancer Genome Atlas RNASeq data set, and correlated with the poor outcome of the patients. In contrast, diversified events, such as tumor growth factor ß1 stimulation, expression of SNAI1 and TP53 mutation, can each cause the induction of ZEB1 and EPB41L5, depending on the cellular context. Our results demonstrated that the ZEB1-EPB41L5 axis is at the core of the cancer mesenchymal program that drives ARF6-based invasion, metastasis and drug resistance of significant populations of primary breast cancers, and is tightly correlated with the poor outcomes of patients.

Predominance of ß-cell neogenesis rather than replication in humans with an impaired glucose tolerance and newly diagnosed diabetes.

CONTEXT: A decrease in pancreatic ß-cell mass is involved in the development of type 2 diabetes. OBJECTIVE: The purpose of this study was to evaluate the ß-cell mass and the incidence of ß-cell neogenesis, replication, and apoptosis at both the prediabetic and diabetic stages. METHODS: We conducted a cross-sectional study of pancreatic tissues obtained from 42 patients undergoing a pancreatectomy who were classified into 4 groups: normal glucose tolerance (n = 11), impaired glucose tolerance (n = 11), newly diagnosed diabetes (n = 10), and long-standing type 2 diabetes (n = 10). RESULTS: The relative ß-cell area decreased and the ß-cell apoptosis increased during the development of diabetes. The number of single and clustered ß-cells, some of which coexpressed nestin, increased in the patients with impaired glucose tolerance and newly diagnosed diabetes. The prevalence of cells positive for both insulin and glucagon or somatostatin also increased in these patients compared with those with normal glucose tolerance. These double-positive cells were mainly localized in single and clustered ß-cells, rather than large islets, and were also positive for Pdx1 or Ngn3. The percentage of insulin-positive cells embedded within ducts increased in the impaired glucose tolerance group. There were no significant differences in the incidence of cells positive for both insulin and Ki67 among the groups. CONCLUSIONS: These results suggest that ß-cell neogenesis, rather than replication, predominates during impaired glucose tolerance and newly diagnosed diabetes in humans and may serve as a compensatory mechanism for the decreased ß-cell mass.

Visualization of angiographical arteriovenous shunting in perisylvian glioblastomas.

BACKGROUND: Arteriovenous shunting visualized by angiography is one of the major features of glioblastomas, and the visualization is dependent on the presence of extensive shunting. Extensive arteriovenous shunting is associated with the risk of poorly controlled intraoperative bleeding. When a tumor with extensive arteriovenous shunting is located in close proximity to the eloquent regions of the brain, a meticulous surgical procedure is necessary. In the present study, the site-oriented visualization of angiographical arteriovenous shunting was evaluated from the perspective of surgical treatment, with a particular focus on the perisylvian region that is in close proximity to motor and language regions (dominant hemisphere), as well as large arteries and veins. METHODS: Twenty-six consecutive patients underwent a resection of glioblastoma between February 2007 and September 2012. All patients were presurgically examined using digital subtraction angiography. The patients were subdivided into the following two groups based on the location of the tumor: 1) perisylvian glioblastoma (18 patients) and 2) non-perisylvian glioblastoma (eight patients). Angiography to detect the arteriovenous shunting was performed. In addition, the number of intratumoral vessels, tumor proliferative activity (MIB-1 labeling index), and volume of intraoperative bleeding were evaluated and compared between the two groups. RESULTS: Angiographical arteriovenous shunting was definitively visualized in 13 of 18 (72 %) perisylvian glioblastomas, in contrast to only one of eight (13 %) non-perisylvian glioblastomas (p = 0.007). There were no significant differences between the two groups with respect to the number of intratumoral vessels, MIB-1 labeling index, and volume of intraoperative bleeding. However, massive intraoperative bleeding of > 2,000 mL occurred in one perisylvian glioblastoma patient. CONCLUSIONS: Glioblastomas in the perisylvian region tend to be associated with extensive arteriovenous shunting that can be definitively visualized by performing an angiography. Because arteriovenous shunting carries the risk of intraoperative bleeding, perisylvian glioblastomas-particularly in the dominant hemisphere-should be resected with a meticulous surgical procedure and strategy.

InN thin film lattice dynamics by grazing incidence inelastic x-ray scattering.

Achieving comprehensive information on thin film lattice dynamics so far has eluded well established spectroscopic techniques. We demonstrate here the novel application of grazing incidence inelastic x-ray scattering combined with ab initio calculations to determine the complete elastic stiffness tensor, the acoustic and low-energy optic phonon dispersion relations of thin wurtzite indium nitride films. Indium nitride is an especially relevant example, due to the technological interest for optoelectronic and solar cell applications in combination with other group III nitrides.

Down-scattered neutron imaging detector for areal density measurement of inertial confinement fusion.

A custom developed (6)Li glass scintillator (APLF80+3Pr) for down-scattered neutron diagnostics in inertial confinement fusion experiments is presented. (6)Li provides an enhanced sensitivity for down-scattered neutrons in DD fusion and its experimentally observed 5-6 ns response time fulfills the requirement for down-scattered neutron detectors. A time-of-flight detector operating in the current mode using the APLF80+3Pr was designed and its feasibility observing down-scattered neutrons was demonstrated. Furthermore, a prototype design for a down-scattered neutron imaging detector was also demonstrated. This material promises viability as a future down-scattered neutron detector for the National Ignition Facility.

Effect of selective vaccination on a decrease in the rate of hepatitis B virus-positive Japanese first-time blood donors.

The government of Japan started a selective vaccination programme to prevent mother-to-infant infection by hepatitis B virus (HBV) since January 1986. The effect of the programme on first-time blood donors has not been examined in detail. Data of first-time blood donors aged 16-25 years from 1996 to 2007 were extracted from the Japanese Red Cross (JRC) donors' database. Principal component analysis (PCA) was used to visualize the birth-year-dependent group of rate of HBV-positive donors. According to the birth of year, donors were divided into four groups by PCA. After the start of the programme, donors born in 1986-1989 comprised a single group. Before the start of the programme, three groups (1980, 1981-1984 and 1985) were identified. Although a significant time-dependent decrease in the rate of HBV-positive donors was observed before the start of the programme, a significant difference in the rate of HBV-positive donors was observed around the start of the programme by regression analysis for 16-19-year-old first-time blood donors. The selective vaccination programme has been effective to prevent the vertical transmission of HBV from the analysis of first-time blood donors. On the other hand, vaccination of blood donors should be considered to reduce the risk of post-transfusion HBV infection, because the horizontal transmission increases in HBV-positive blood donors.

A new method of concentrating hepatitis B virus (HBV) DNA and HBV surface antigen: an application of the method to the detection of occult HBV infection.

BACKGROUND: The risk of post-transfusion hepatitis B virus (HBV) infection has been reduced after the implementation of HBV nucleic acid amplification technology (NAT). However, the problem of HBV DNA-positive and HBV surface antigen (HBsAg)-negative occult HBV infections remains to be solved. This is in part due to the HBV DNA load being too low to detect these occult HBV infections using mini-pool NAT. In Japan, the assay for the antibody against the HBV core antigen (anti-HBc) has not completely excluded occult HBV infection. To solve this problem, we have developed a new method of concentrating HBV DNA and HBsAg simultaneously to increase the sensitivity of detection tests. METHODS: Virus concentration is achieved by the enhancement of the agglutination of viruses using poly-L-lysine in the presence of a bivalent metal. Poly-L-lysine-coated magnetic beads are used to shorten the time of each step of the concentration procedure. Seventy-seven anti-HBc-positive and HBsAg-negative donations were examined. HBsAg and anti-HBc were tested by enzyme immunoassay (EIA) (AxSYM; Abbott) and haemagglutination inhibition test (Japanese Red Cross), respectively. RESULTS: HBV surface antigen and HBV DNA levels were concentrated up to four- to sevenfold. Using this method, 35 of the 77 anti-HBc-positive and HBsAg-negative donors were HBV DNA-positive by individual NAT and a further five donors became HBV DNA-positive by HBV concentration. Twenty-seven of 40 occult HBV infections became HBsAg-positive by HBsAg concentration. CONCLUSION: Our new method of concentrating HBV and HBsAg increased the sensitivities of EIA and HBV NAT, and enabled us to detect 27 of 40 occult HBV infections by HBsAg EIA.

The useful combination of a higher frequency miniprobe and endoscopic submucosal dissection for the treatment of T1 esophageal cancer.

BACKGROUND: There are few published data on the discrimination ability of endoscopic ultrasonography (EUS) among each subdivision of T1 cancer, and overdiagnosis is an unsolved problem that eventually causes overtreatment. The purpose of this study was to verify whether our treatment strategy incorporating EUS realizes a tailored patient management of T1 esophageal cancer. METHODS: This study comprised 20 esophageal cancer patients undergoing 12- to 20-MHz miniprobes for T staging and a 7.5-MHz dedicated echoendoscope for N staging. Initial therapy constituted endoscopic submucosal dissection (ESD) for endosonographically node-negative, mucosal, or slight submucosal cancers and a primary esophagectomy with three-field lymphadenectomy for deeper cancers. If the ESD specimen revealed no cancer involvement of the muscularis mucosa, the patients entered a follow-up program; otherwise, they were advised to undergo a subsequent esophagectomy and three-field lymphadenectomy. RESULTS: Perfect discrimination accuracy was achieved among T1, T2, and T3 cancers. Whether cancer depth was up to the slight submucosal layer or deeper was correctly differentiated in 12 of 14 T1 cancers (86%). EUS categorized all patients correctly into candidates for either ESD or surgery. The pathological cancer depth of the resected specimens revealed that no patients experienced unnecessary overtreatment. CONCLUSIONS: A higher frequency miniprobe is useful for the detailed evaluation of cancer depth, contributing to decision making for treatment options of T1 esophageal cancer. A miniprobe and echoendoscope in combination with ESD provide an appropriately tailored management plan on an individual basis, avoiding unnecessary treatment or indicating radical surgery.

Epidemiology of blood donors in Japan, positive for hepatitis B virus and hepatitis C virus by nucleic acid amplification testing.

BACKGROUND AND OBJECTIVES: The Japanese Red Cross screens seronegative blood donors by nucleic acid amplification testing (NAT) for hepatitis B, hepatitis C and human immunodeficiency virus-1 markers. NAT-positive donors thus identified seemed to have a different infectious background from serologically positive donors. The purpose of our study was to characterize this background in the hepatitis B virus (HBV) and hepatitis C virus (HCV) NAT-positive donors. MATERIALS AND METHODS: Some 328 HBV DNA-positive and 44 HCV RNA-positive donors were detected by NAT testing of seronegative blood donors. These were characterized regarding age, gender and genotype of HBV and HCV. RESULTS: Those who were HBV NAT-positive were mainly young, in particular teenage girls. In Japan, genotypes C and B have previously been dominant, but recently genotype A has increased, and genotype H was recently detected. In HBV NAT-positive donors, the rate of genotype A was high (12.2%) compared with patients in hospital (1.7-2%). Donors who were HCV NAT-positive were also young, but mostly men in their twenties. The ratio of genotype 1b to 2a or 1b to 2b in HCV NAT-positive donors differed from that of hospitalized patients in Japan. We did not find genotype 1a, which is dominant in the USA. CONCLUSIONS: The high-risk donors detected by NAT were mainly young, with a different distribution of genotypes from that of hospitalized patients, regarding both HBV and HCV. The rare HBV genotype H has been found for the first time in Japan. The findings reflect the present spread of hepatitis viruses B and C.

Functional modulation of activated lymphocytes by time-varying magnetic fields.

Time-varying magnetic fields (TVMF), especially those of extremely low frequency (below 250 Hz), have been reported to have profound effects on biological systems due to the induced currents since the biological systems consist of electrolyte solution. We have been interested in utilizing TVMF for cellular immunomodulations, and have shown that the TVMF could augment macrophage activation. In this study, the effect of TVMF on lymphocyte activation was studied. Murine spleen lymphocytes were isolated from DDY mice and incubated in the presence of Concanavalin A (ConA) for 72 h. The lymphocytes were exposed to TVMF for various durations, from 20 min to 2 h. The proliferation activities of lymphocytes were assayed by ELISA by use of 5-bromo-2'-deoxy-uridine Labeling and Detection Kit III (Roche Diagnostic Corp. Indianapolis, IN, USA). The IL1beta and IL2 concentrations in the culture medium were measured by ELISA assay. The IL2 receptor expression on the lymphocytes was evaluated by FACS analysis by use of FITC-conjugated monoclonal antibody. The proliferation activities were significantly enhanced by the TVMF for up to 40 min exposure from the initiation of ConA stimulation. The degree of augmentation effects, defined by the ratio of activation index of with and without TVMF, was varied from 1.1 to 2.7, and related to the lymphocyte responsiveness to the ConA. The less responsive cells showed more TVMF augmentation effects. The TVMF exposure after 40 min from ConA addition showed no effect, suggesting that the TVMF effects are most likely related to the Ca ion influx. The prolonged exposure of TVMF depressed the augmentation effects, which was caused by the depressed IL-2 receptor expression although both IL1-beta and IL-2 productions were not affected.

Capacity of the horizontal vestibuloocular reflex motor learning in goldfish.

The vestibuloocular reflex (VOR) stabilizes visual image on the retina during head motion by counter-rotating the eyes in the orbit. It indicates a type of learning called motor learning by which changes in system characteristics due to development, aging etc. are adaptively compensated to achieve visual stabilization. Presently, we evaluated the capacity of the horizontal VOR motor learning in goldfish to argue the limitation in their learning ability and to identify the neuronal sites that is capable of achieving the learning task. We demonstrate that goldfish VOR can be modified in the opposite directions for right and leftward head rotations simultaneously. The roles of cerebellum to achieve this learning are discussed.

Superiority of minipool nucleic acid amplification technology for hepatitis B virus over chemiluminescence immunoassay for hepatitis B surface antigen screening.

BACKGROUND AND OBJECTIVES: The Japanese Red Cross (JRC) have developed a fully automated multiplex (MPX) nucleic acid amplification technology (NAT) system for hepatitis B virus (HBV), hepatitis C virus (HCV) and human immunodeficiency virus 1 (HIV-1). This is used to test serologically negative blood units from volunteer, non-remunerated donors. The system utilizes a 50-sample pool for NAT screening with an input volume of each pool. This results in a significantly higher sensitivity for hepatitis B than that seen with highly sensitive hepatitis B surface antigen (HBsAg) testing. MATERIALS AND METHODS: From 1 February 2000 to 15 October 2001, over 11 million donations, which were serologically negative, were tested using the MPX NAT system. Donations found to be HBV DNA positive were further tested by using the chemiluminescence immunoassay (CLIA). RESULTS: Out of 181 HBV DNA-positive donations, 96 (53%) and 76 (42%) were negative by individual enzyme immunoassay (EIA) and CLIA testing, respectively. CONCLUSIONS: The sensitivity of the 50-sample pool MPX NAT system was higher than that of individual HBsAg screening by CLIA. By adopting this NAT-screening system, the JRC has improved the safety of the blood supply and maintained supply across Japan.

Status of NAT screening for HCV, HIV and HBV: experience in Japan.

The first nationwide nucleic acid amplification testing (NAT) for hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus type 1 (HIV-1) of voluntarily donated blood after serological pre-screening and before release of cellular components and plasma for fractionation was implemented by the Japanese Red Cross Blood Transfusion Services. The NAT screening assay using multiplex reagent is time-saving, cost effective, and labour-saving procedure for all blood and blood products including short-shelf life platelets. During the 50-mini-pool NAT screening of serologically negative donations (February 1, 2001-April 30, 2001), we were able to screen out 112 HBV-positive, 25 HCV-positive, and 4 HIV-1 positive units from blood and blood components.

Analysis of the entire genomes of thirteen TT virus variants classifiable into the fourth and fifth genetic groups, isolated from viremic infants.

TT virus (TTV) DNA in serum samples obtained from 24 TTV-infected infants was amplified by polymerase chain reaction (PCR) with inverse primers derived from the untranslated region. The amplified PCR products were molecularly cloned; six clones each were analyzed. Seventy-six (53%) of the 144 TTV clones were classified into group 4 (YONBAN isolates), and 22 (15%) into a novel genetic group (group 5). The TTV clones in group 4 were classified into 9 types, and those in group 5 into 4 types. The entire nucleotide sequence of one representative clone each from the 13 types were determined; they comprised 3570-3770 nucleotides, and had poor homology to TTVs of groups 1-3 (TA278, PMV and SANBAN isolates). A phylogenetic tree based on the entire nucleotide sequence of open reading frame 1 confirmed the presence of five distinct clusters separated by a bootstrap value of 100%. Analysis of 13 TTV variants demonstrated preservation of the genomic organization and transcription profile in all TTV groups. TTV group 4 was detected in 54% or 72% of 7-to-12-month-old infants in Japan and China, respectively, which is comparable with that among adults in the respective country, indicating early and frequent acquisition of this TTV group in infancy.