Surface smoothing of additively manufactured Ti-6Al-4V alloy by combination of grit blasting and large-area electron beam irradiation

Additively manufactured (AMed) titanium products are typically produced by electron beam melting (EBM), since oxidation of titanium alloy surface can be suppressed in vacuum environment. The surface roughness of AMed titanium products becomes more than 200 µm Rz, and the very rough surface would lead to reduction in fatigue strength. Therefore, a post surface finishing process is required. Abrasive blasting is one of the common surface smoothing processes of AMed metal products. Large surface roughness can be decreased, and compressive residual stress can be introduced to the surface. However, there is a limitation to reduction of surface roughness to several µm Rz. On the other hand, it was recently found that AMed metal surface produced by powder bed fusion with laser beam could be smoothed by large-area electron beam (LEB) irradiation. However, it is difficult to smooth surface with large initial surface roughness, and a tensile residual stress may be generated on the surface. In this study, surface smoothing and change in residual stress of AMed titanium alloy (Ti-6Al-4 V) were proposed by combination of grit blasting and LEB irradiation. Surface roughness of AMed Ti-6Al-4 V alloy significantly decreases from 265 to about 2.0 µm Rz by combination of grit blasting and LEB irradiation. Reduction rate of surface roughness by LEB irradiation linearly increases with decreasing mean width of blasted surface. Influence of the mean width on smoothing effect by LEB irradiation can be explained by thermo-fluid analysis. Moreover, tensile residual stress caused by LEB irradiation can be reduced when LEB is irradiated to blasted surface

The secretion of high molecular weight cathepsin B from cultured human liver cancers.

The biochemical characteristics of cathepsin B secreted from cultured human liver cancer cells were examined. The enzyme activity of culture medium against a synthetic substrate, N-carbobenzoxy-L-arginyl-L-arginine-4-methyl-coumaryl-7-amide, was dependent on the addition of cysteine, and the optimal pH was found to be 6.0. No activity was observed when the enzyme source was fresh medium not used for culture. These results suggest that the enzyme released from liver cancer cells is the thiol-protease cathepsin B. The molecular weight of the enzyme with 90% of the total activity was 40,000. Two cathepsin B molecules were found in liver tissue from patients with hepatocellular carcinoma (HCC); one was equivalent in size to the secreted enzyme, and a smaller one was the same as normal liver cathepsin B (27,000), which was also obtained from HCC-bearing cirrhotic liver. These results demonstrate that two molecules of cathepsin B are synthesized in liver cancer, and that the larger one is released into the surrounding tissue.</p

Ixia から分離された bean yellow mosaic virus

A strain (Ixia-B) of bean yellow mosaic virus (BYMV) isolated from Ixia hybrida was characterized and compared with other isolates of BYMV and clover yellow vein virus (CYVV). Ixia-B was transmitted by aphids,Myzus presicae in a non-presistent manner and by sap-inoculation to 11 of 46 species in 5 of 10 families tested, and had a similar host range to that of some BYMV isolates, althrough some defferences were detected. Sap from diseased C. quinoa was infective after 10 min heating at 55℃ but not 60℃, after a dilution to 10-3 but not 10-4, and after 2 days but not 4 days at 20℃.The Virus particles were filamentous rods of about 13×820 nm. Ixia-B contaied a single protein species with a molecular weight of 34,000 and a single viral RNA with approximately 9,000 bases. In ultrahtin sections of leaf tissues from infected plants, the virus particles, cylindrical cytoplasmic inclusions and dense bodies were obsserved in the cytoplasm. The antiserum to Ixia-B produced by immunizing a rabbit had a titer of 1/512. A close serological relationship was revealed between Ixia-B and two strains of BYMV from crocus and gladiolus, but no relationship to clover yellow vein virus was found in agar gel diffusion tests. However,Ixia-B could be distinguished from two strains of BYMV by the formation of spurs among them in agar gel and by the differences in the patterns of peptide mapping of coat proteins. From these findings, Ixia-B was identified as a strain of BYMV.1992年に岡山県倉敷市玉島で、葉に斑入りを生じた球根類花卉植物Ixia hybridaからpotyvirus(Ixia-B)が分離され、その諸性質から　bean yellow masaic virus(BYMV)と同定された。本ウイルスを11科47種の植物に接種したとこと、フリージャ、Nicotiana clevelandii、Chenopodium amaranticolar、ソラマメ、クリムソンクローバー、インゲンマメ、ホウレンソウに全身感染し、またC.quinoa、フダンソウ、ツルナ、センニチコウなどに局部感染したが、エンドウ、ササゲ、ダイズなどには感染しなかった。本ウイルスをはモモアカアブラムシにより非永続的伝搬され、C.quinoa の病葉粗汁液中での安定性は耐熱性が55℃～60℃（10分）、耐希釈性10-3～10-4、耐保存性2～4日であった。DN法試料の電顕観察で多くのpotyvirusよりやや長い約820nmのひも状粒子と管状封入体の破片が見られた。感染葉の超薄切片では風車状、層板状の封入体、dence body、細胞質に散在するウイルス粒子が観察された。本ウイルスはfreesia mosaic virusおよびclover yellow vein virusの抗血清と反応せず、また本ウイルス抗血清を用いた寒天ゲル内二重拡散法ではBYMV分離株（Cro-4, BYMV-G）と反応したが、本ウイルスとBYMVのCro-4およびBYMV-G間にspurが形成され、異種抗原の存在が認められた。外被タンパク質の分子量は約34Kで、ssRNAのサイズは約9Kbであった。Papain,chymotrypsin,pepsinを用いた外被タンパク質のぺプタイドマッピングでは、本ウイルス、Cro-4、BYMV-G、Cal-35の部分分解パターンがそれぞれ異なり、外被タンパク質がアミノ酸配列レベルで異なっていることが示唆された

Development of hydroxyapatite-coated nonwovens for efficient isolation of somatic stem cells from adipose tissues

Adipose-derived stem cells (ASCs) are an attractive cell source for cell therapy. Despite the increasing number of clinical applications, the methodology for ASC isolation is not optimized for every individual. In this study, we developed an effective material to stabilize explant cultures from small-fragment adipose tissues. Methods: Polypropylene/polyethylene nonwoven sheets were coated with hydroxyapatite (HA) particles. Adipose fragments were then placed on these sheets, and their ability to trap tissue was monitored during explant culture. The yield and properties of the cells were compared to those of cells isolated by conventional collagenase digestion. Results: Hydroxyapatite-coated nonwovens immediately trapped adipose fragments when placed on the sheets. The adhesion was stable even in culture media, leading to cell migration and proliferation from the tissue along with the nonwoven fibers. A higher fiber density further enhanced cell growth. Although cells on nonwoven explants could not be fully collected with cell dissociation enzymes, the cell yield was significantly higher than that of conventional monolayer culture without impacting stem cell properties. Conclusions: Hydroxyapatite-coated nonwovens are useful for the effective primary explant culture of connective tissues without enzymatic cell dissociation

Notch activates cell cycle reentry and progression in quiescent cardiomyocytes

The inability of heart muscle to regenerate by replication of existing cardiomyocytes has engendered considerable interest in identifying developmental or other stimuli capable of sustaining the proliferative capacity of immature cardiomyocytes or stimulating division of postmitotic cardiomyocytes. Here, we demonstrate that reactivation of Notch signaling causes embryonic stem cell–derived and neonatal ventricular cardiomyocytes to enter the cell cycle. The proliferative response of neonatal ventricular cardiomyocytes declines as they mature, such that late activation of Notch triggers the DNA damage checkpoint and G2/M interphase arrest. Notch induces recombination signal-binding protein 1 for Jκ (RBP-Jκ)-dependent expression of cyclin D1 but, unlike other inducers, also shifts its subcellular distribution from the cytosol to the nucleus. Nuclear localization of cyclin D1 is independent of RBP-Jκ. Thus, the influence of Notch on nucleocytoplasmic localization of cyclin D1 is an unanticipated property of the Notch intracellular domain that is likely to regulate the cell cycle in multiple contexts, including tumorigenesis as well as cardiogenesis

Yeast functional assay of the p53 gene status in human cell lines maintained in our laboratory

We used a yeast functional assay (functional analysis of separated alleles in yeast: FASAY) to determine the p53 gene status of human cell lines maintained in our laboratory. This assay enables the researcher to score wild-type p53 expression on the basis of the ability of expressed p53 to transactivate the reporter gene HIS 3 via the p53-responsive GAL 1 promoter in Saccharomyces cerevisiae. The cell lines examined were ten hepatoma, two hepatoblastoma, three in vitro immortalized fibroblast, two osteosarcoma, a chondrosarcoma, an ovarian teratocarcinoma and a colon cancer cell line. Out of 20 cell lines, 11 cell lines had mutations in both alleles of the p53 gene, and another 8 cell lines had no mutation in the p53 gene. Thus, 55% of the cell lines examined had mutations in the p53. Interestingly, PA-1 cells had both the normal and the mutant p53 alleles, showing that FASAY is a useful method for detecting the wild-type and mutated p53 genes simultaneously. As for the three liver cell lines harboring HBsAg, there was no relationship between their p53 gene status and the presence of HBsAg. Two cell lines were normal for p53 status, while the other had a mutation of the p53 gene.</p

Comparison of cellular characteristics between human hepatoma cell lines with wild-type p53 and those with mutant-type p53 gene

Characteristics of human hepatoma cell lines with the wild-type p53 were compared with those of human hepatoma cell lines with the mutant-type p53. The p21 protein located downstream of p53 was expressed in cell lines with the wild-type p53 but was not expressed in cell lines with the mutant-type p53. As to other tumor suppressor genes such as p16 and p27, there was no difference in their expression between both types of cell lines. In addition, no marked difference was observed in the activities of CDK2 and CDK4 between cell lines with the wild-type and the mutant-type p53. Phosphorylated Rb protein was detected in all cell lines except the HLE line, indicating that this cell line may have a deletion of and/or a mutation of the Rb gene. These results indicate that abnormalities of tumor suppressor genes other than p53, p16, p27, and Rb may be involved in hepatocarcinogenesis. The population doubling time of the wild-type p53 cells was significantly longer than that of the mutant p53 cells. Neither type of cell line showed a specific chromosome distribution which would indicate karyotype instability. The cell lines expressing the wild-type p53 produced tumors at lower frequency than those with the mutant p53 gene. Although there was no significant difference in effects of TGF-&#946;1, EGF, cholera toxin, and db-cAMP on cell growth between the two types of cells, all three cell lines with the wild-type p53 were resistant to cytotoxicity of TNF-&#945;, while two of the three with the mutant p53 were very sensitive to its cytotoxic effects.</p

Wearing graduated compression stockings augments cutaneous vasodilation but not sweating during exercise in the heat

The activation of cutaneous vasodilation and sweating are essential to the regulation of core temperature during exercise in the heat. We assessed the effect of graduated compression induced by wearing stockings on cutaneous vasodilation and sweating during exercise in the heat (30°C). On two separate occasions, nine young males exercised for 45 min or until core temperature reached ~1.5°C above baseline resting while wearing either (1) stockings causing graduated compression (graduate compression stockings, GCS), or (2) loose‐fitting stockings without compression (Control). Forearm vascular conductance was evaluated by forearm blood flow (venous occlusion plethysmography) divided by mean arterial pressure to estimate cutaneous vasodilation. Sweat rate was estimated using the ventilated capsule technique. Core and skin temperatures were measured continuously. Exercise duration was similar between conditions (Control: 42.2 ± 3.6 min vs. GCS: 42.2 ± 3.6 min, P = 1.00). Relative to Control, GCS increased forearm vascular conductance during the late stages (≥30 min) of exercise (e.g., at 40 min, 15.6 ± 5.6 vs. 18.0 ± 6.0 units, P = 0.01). This was paralleled by a greater sensitivity (23.1 ± 9.1 vs. 32.1 ± 15.0 units°C−1, P = 0.043) and peak level (14.1 ± 5.1 vs. 16.3 ± 5.7 units, P = 0.048) of cutaneous vasodilation as evaluated from the relationship between forearm vascular conductance with core temperature. However, the core temperature threshold at which an increase in forearm vascular conductance occurred did not differ between conditions (Control: 36.9 ± 0.2 vs. GCS: 37.0 ± 0.3°C, P = 0.13). In contrast, no effect of GCS on sweating was measured (all P > 0.05). We show that the use of GCS during exercise in the heat enhances cutaneous vasodilation and not sweating

EGFR Down-regulation Predicts anti-EGFR Response

ABC, antibody-binding capacity; ADCC, antibody-dependent cellular cytotoxicity; ATCC, American Type Culture Collection; BSA, bovine serum albumin; CR, complete response; CRC, colorectal cancer; CT, computed tomography; ECACC, European Collection of Authenticated Cell Cultures; EGF, epidermal growth factor; EGFR, epidermal growth factor receptor; ETS, early tumor shrinkage; FBS, fetal bovine serum; FISH, fluorescent in situ hybridization; HRP, horseradish peroxidase; HSRRB, Health Science Research Resources Bank; IHC, immunohistochemistry; MesNa, Mercaptoethanesulfonic acid sodium; mCRC, metastatic colorectal cancer; mAb, monoclonal antibody; mAbs, monoclonal antibodies; PARP, poly (ADP-ribose) polymerase; PBS, phosphate buffered saline; PD, progressive disease; p-ERK, phosphorylated ERK; PNA-LNA, peptide nucleic acid-locked nucleic acid; PR, partial response; PVDF, polyvinylidene difluoride; RECIST, Response Evaluation Criteria in Solid Tumors; RIKEN BRC, RIKEN BioResource Center; SD, stable disease; SDS, sodium dodecyl sulfate; SDS-PAGE, SDS-polyamide gel electrophoresis; TBS-T, Tris-buffered saline with 0.1% Tween; TGF-α, transforming growth factor-α