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Ultra-high molecular weight polyethylene (UHMWPE) has been widely used as a bearing surface of joint implants. Since wear of UHMWPE component has been the primal cause of implant failure, crosslinking of UHMWPE is now widely used to improve its wear property. On the other hand, crosslinking degrades its fatigue property and increase of fatigue related failure, such as delamination, is possible. However, the relationship between degraded fatigue property and implant failure is not clear, primarily because the fatigue properties of failed and retrieved UHMWPE components are not known. In this study, we propose a new test method to evaluate the fatigue property of retrieved UHMWPE components or final products using small specimens. First, the effects of test conditions were investigated using virgin UHMWPE. Then, tests were repeated using specimens from UHMWPE components of retrieved knee implants. The fatigue properties of virgin and retrieved UHMWPE were suc- cessfully evaluated by the new test method and a relationship was found among the extent of oxidation, the fatigue property, and occurrence of delamination. This result suggested that evaluation of fatigue property of UHMWPE component can predict the occurrence of fatigue related implant failure during operation in vivo.

An integrated optical micro-displacement sensor was developed that uses the beam diverging from a vertical cavity surface emitting laser (VCSEL). The sensor consists of a VCSEL ( 1.5 mm × 1.5 mm × 1.2 mm ) that is surrounded by three photodiodes and can measure the linear distance traveled and the tilting angle of an external mirror. The resolution is 20 nm for a measurement range up to 0.4 mm, or less than 40 nm for a wider measurement range of 1.8 mm. The full range of the measurable tilting angle is 5 ° . This sensor can be incorporated into devices with micro-mirrors, such as integrated scanning microscopes.

To apply human mesenchymal stem cells (hMSC) to regenerative medicines, it is necessary to multiply hMSC in vitro in a short period. In addition, it is desirable that the medium which is used for the hMSC multiplication is not supplemented with the serum, because the addition of the serum has risks of infection. In this study, we cultured hMSC with three kinds of medium used for multiplying hMSC (DMEM, MSCGM, STK2) and compared hMSC proliferation in each medium. As a result, it was confirmed that hMSC proliferation was significantly higher in STK2 medium which is a novel serum-free medium developed for hMSC multiplication. Moreover, we compared the hMSC proliferation in these media under the environment that assumed bone reproduction. When we cultured hMSC in each medium with hydroxyapatite (HAp), the proliferative inhibition by HAp depended on the additive amount, and the degree of the proliferative inhibition was different among the media but the lowest inhibitory effect was observed in STK2 medium.

チャボリュウノヒゲの大量増殖手法を確立するため, 生長調節物質の濃度と種類を違えたMS培地で茎頂分裂組織を培養した。その結果, 無菌再生個体が得られ組織培養による本種の増殖の可能性を確認した。α-ナフタレン酢酸は高濃度の時にカルスを, 低濃度の時に根を誘導し, その違いに関係なくシュートの成長を促進すること, 6-ベンジルアミノブリンは, シュートを誘導し, α-ナフタレン酢酸の効果を抑制することがほぼ明らかになった。

ニワゼキショウの群生地の形成手法を確立するため, 種子の発芽と生育習性, および刈取り抵抗性を調べた。その結果, 種子の発芽には光の照射が要求され, 発芽適温が15～20℃ にあった。花期は5～11月で, 葉は常緑に近い性質を持ち, 主に, 4～9月は地下部の養分と地上での生産養分によって, 地上部の栄養と繁殖成長を行い, 9～11月に生産養分を地下部に蓄積した。2週毎刈取りでは枯死し, 群生地形成における最適下刈り頻度は4週毎であった。

Changes in the clay mineralogy in a chronosequence of polder soils cultivated with paddy rice for 15, 75, 150, and 265 years in Kojima Basin were studied. Parent materials of each profile appeared to be homogeneous. Prolonged paddy cultivation (150 and 265 years) brought about some modification in the clay mineralogy of Ap horizons, while the mineralogical changes were not evident in the profiles less than 75 years of age. Characteristic changes consisted of the formation of 18-25 A minerals, which were composed of interlamellar humus-smectite complexes and interstratified minerals. The interstratification showed intermediate stages from smectite to kaolin minerals along with partial chloritization of smectite. The interstratification and partial chloritization of smectite caused the CEC of the clay fractions of Ap horizons to decrease partly.

オオスギゴケの張り苔の生産手法を検討するため, 火山灰赤色土 (赤土) と花崗岩風化土 (キラ土) 及びこれに真珠岩パーライトM1, M3, バラス砕石を混合させた実験用上において, 蒔き付けた木種の生茎葉から個体成立状況を比較した。茎葉をキラ土に蒔くと, 栄養繁殖により増殖は良好であるが, パーライトM3を30%混合させると最大の生長が得られた。この場合の蒔き付け後7カ月目の成立茎数は, 4.5木/cm2植被率は90%に達した。

P-nitrosodimethylaniline (P-NSDA), one of the OH radical (OH·) scavengers, inhibited platelet aggregation by ADP or arachidonic acid (AA), inducing a certain alteration in platelet phospholipid metabolism.In the platelet aggregation, it has been reported that reactive oxygen species, OH·, is generated in the process of the concomitant AA metabolism, and modified the rate and extent of various reactions in it. Then, we studied the effects of OH· scavengers on platelet aggregation.Washed rabbit platelets were incubated at 37°C for 4min with OH· scavengers (P-NSDA, thiourea, D-mannitol, urea and methional), lipoxygenase inhibitor (nordihydroguaiaretic acid; NDGA) or cyclooxygenase inhibitor (benzoic acid; BA) before aggregation was induced. P-NSDA inhibited ADP or AA-induced platelet aggregation about 70-80% in comparison with control, but other OH· scavengers had no effects on ADP, AA, thrombin or A23187-induced aggregation. On the other hand, BA and NDGA inhibited AA or ADP-induced aggregation and their inhibition patterns were similar to that of P-NSDA. So, we considered that the inhibition of P-NSDA on ADP or AA-induced aggregation was not induced by its effect of trapping OH· but by altering the phospholipid metabolism associated with the platelet aggregation.To confirm these considerations, we tried to analyze phospholipid metabolites during AA-induced platelet aggregation treated with P-NSDA by TLC.In the results, it was found that the pattern of TLC in the platelet treated with P-NSDA was greatly different from those treated with inhibitors of AA metabolism, such as aspirin and NDGA. These findings indicate that the inhibition of the platelet aggregation by P-NSDA relates with other phospholipid metabolism than AA metabolism in platelet associated with platelet aggregation and that P-NSDA may be useful for investigating phospholipid metabolism in platelet aggregation.

室温16-28℃に自動制御されたガラス室で, ゼラニウムの9品種を, 最近, 省力化育苗技術として期待されているプラグ苗生産容器において挿し木増殖させた.供試品種は, 花ゼラニウムP.hortorumの2系統5品種と, アイビーゼラニウムP.peltatumの4品種とし, 供試用土は, バーミキュライトと真珠岩パーライトM2を容積比で同量混合した用土とした.その結果, 供試9品種中7品種の発根率は, 挿し木後の経過日数が40日目において, 最高値の80%以上に達した.しかし, その後50日まで経過させても発根率は向上せず, 逆に根腐れなどを招くことが判明した.また, 花ゼラニウムの2品種を用い, 鉢上げ時期を挿し木後30日目, 40日目, 50日目と違えた場合, 生育に及ぼすその影響は供試品種間で異なったが, 挿し木後40日目に鉢上げした場合の生育は両品種において良好となった.したがって, ゼラニウムのポット苗生産上の最適鉢上げ時期は, 挿し木後40日目であることがほぼ把握された.一方, 低コスト大量生産に適した花ゼラニウムの系統は発根率, 1株当りの腋芽数の増加に優れたエキストラ系であり, レッドハートは'特に有望な品種であると考えられた.

The spreading of blood platelets after adhesion was first observed by Eberth et al. (1885) and has been studied since by many investigators. The underlying mechanisms, however, are not known in many respects and there has been no report so far of its electron microscopic observation.PURPOSE: For making observation of the mode of normal platelet adhesion and spreading by scanning electron microscopy as well as to investigate morphological changes of spreading platelets in elected hematologic disorders.SUBJECTS: The mechanism of platelet spreading was investigated with specimens from healthy male adults, followed by comparison of the spreading of plateles from patients with C. M. L. or I. T. P.PROCEDURE: Platelets were allowed to spread on plastic plates by the method of Breddin and fixed after intervals of 5, 15 or 30 minutes for microscopic observation. Those from patients were fixed after 30 minutes of spreading. For electron microscopy, specimens were fixed with 1% glutaraldehyde and, after postfixation in 1% OsO4, they were dehydrated, dried and covered by the vacuum evaporation of carbon and metal.RESULTS: Mode of spreading—At 5 minutes of spread each platelet was found to have sent out one or two pseudopodia. When 15 minutes had elapsed the pseudopodia were found increasing in number and elongated to shape up a dendritic form. At 30 minutes, the platelet was spread to assume a discoid shape with the peripheral transparent hyalomere and the central portion consisting of a gel-like material. A series of scanning electron micrographs shows that, generally speaking, the platelet sends out pseudopodia which thereafter increase in number and extend to form dendroid structures with a subsequent formation of the hyalomere just like a membrane spreading around neighboring pseudopodia; the platelet thereby gradually spreads into an ellipsoid shape. An occasional platelet shows the formation of a clear zone by a sol-like outflow around the pseudopodia, followed by its confluence with the substance from the central portion to eventually make the platelet discoid. It was also noted that a platelet had a peripheral clear zone formed around it at as early as the initial stage of adhesion and thereafter appeared to continue spreading in all directions; it remains yet to be determined whether or not this represents the consequences of a rapid progress in platelet spreading in either of the foregoing two fashions. Platelets from patients—Most platelets from CML patients were found asteroid with incompletely spread peripheral dendroid structures. In ITP, platelets were ellipsoid and displayed remarkably active spreading; the central portion consisted of a gel-like substance with an irregularly uneven surface and with trabeculations around it.CONCLUDION: Blood platelets were observed to spread in three different modes, and this finding would be of significance as an aid to elucidation of the process of platelet adhesion. The observation also disclosed a remarkably striking difference in the morphology of platelet spreading between CML and ITP, suggesting likely abnormalities of platelet function in these conditions.

Platelet aggregation test was originated from Breddin which determined degree of platelet aggregation in vitro by mechanical stimuli such as contact of platelets on siliconized glass surface. We have carried out the PAT test using 45 subjects including 6 patients with ITP, 5 with uremia, 7 with hepatitis, 6 with carcinoma, 13 with other miscellaneous diseases and 9 healthy volunteers. In the result of PAT test, degrees of platelet aggregation were graded to I-V scales. At the same time, platelet spreadability (PSA) test following Breddin and ADP-induced platelet aggregation test were performed. We have modified PSA test to use a pair of clean plastic slide arranging parallel with one cm in distance in which the specimen was filled. Using this modified method, a reasonably high reproducibility was obtained. The degree of PSA was recorded as mean diameters of spreading platelets on plastic surface. In ADP-induced aggregation, 10μM ADP was added into platelet rich plasma using Evans aggregometer. In 8 out of 9 healthy subjects, grade III PAT was observed, whereas in 5 ITP patients, markedly lowered ability of platelets to aggregate grade I was observed. The PAT was found enhanced in the cases of uremia. Most patient with carcinoma displayed an enhanced PAT while it was depressed in the few remainders. Statistical analysis of the data revealed no significant interrelation between PAT and PSA. However, the combination with both the test, characteristic changes were noted in each of diseases. There was a statistical evidence of significant correlatation between PAT and ADP-induced platelet aggregation, with the equation of regression:Y=1.72+0.28X, r=0.492, P=0.02The above results would suggest that PAT and PSA test may be useful to determine some clinical conditions, when both the methods are used in a combination.

Peripheral and bone marrow leukocytes from 24 leukemic patients (including 5 patients with DIC) were analysed for coagulant and fibrinolytic activity. Suspension of leukocytes were prepared by dextran method. Washed preparations were disrupted by freezing and thawing three times and homogenized. Lysates of these leukocytes were added into prothrombin time system instead of lyoplastin (rabbit lung tissue thromboplastin). For comparison, leukocytes from 10 normal donnors were tested. Antithrombin III, fibrinogen, prothrombin and FDP were simultaneously measured and these change in clinical courses were compaired with leukocytic thromboplastin like activity.Lysate of these leukocytes from peripheral and bone marrow in cases of leukemia with DIC showed high coagulant activity in prothrombin time system. FDP increased and antithrombin III, prothrombin and fibrinogen decreased. However lysate of leukemia without DIC showed normal or lower leukocytic thromboplastin like activity in prothrombin time system and FDP, antithrombin III, prothrombin and fibrinogen were not so changed. The coagulant activity of the lysate of AMMoL was intermediate between DIC and non DIC. In clinical courses of leukemic therapy, leukocytic thromboplastin like activity was relatively related to number of leukemic cells. The cases with high leukocytic thromboplastin like activity before chemotherapy have an anxierty to induce DIC.We think that leukocytic thromboplastin like activity is related to DIC in leukemia.

The influence of various acid glycosaminoglycans on the platelet spreadability (PSA) was studied, along with the platelet aggregation test (PAT) and ADP aggregation test.Acid glycosaminoglycans; chondroitin-6-sulfate (chondroitin A) dermatan sulfate (chondroitin B) and chondroitin-4-sulfate (chondroitin C) present in vascular endothelirium and heparin, amyropectin sulfate, amylose sulfate, glycogen sulfate and glycogen were added to PRP at the concentration of 0.0025mg/ml after 15 minutes, the number of platelets adhering to the plastic plate was counted to ovserve the spreading of platelet. PAT was conducted by Breddin I method and ADP aggregation induced by 10-5M. ADP was measured in the same sample.Addition of chondroitin C resulted in a marked decrease of the plastic plate adhesion on the plastic plate with disturbance of platelet spreading, indicating a definite inhibition of PSA. PAT was mildly inhibited. Chondroitin A and B mildly inhibited PSA but the responses of PAT were variable. Heparin definitely augmented both PAT and PSA with an increase of platelet adhesion on plastic plate. Amylose sulfate and amylopectin sulfate failed to influence the spreading definitly. While glycogen sulfate augmented PAT and PSA, glycogen exerted no such action. No difinite change occurred in aggregation in response to any of these substances tested.Three of the acid glycosaminoglycans present in the vascular endothelium inhibited platelet spreading and interfered with the platelet adhesion to the plastic plate. Especially chondroitin C most abundantly found with in the endothelium showed a marked inhibitly effect. Heparin, on the contrary, interestingly augmented platelet adhesion at 0.0025mg/ml. Other acid glycosaminoglycans showed no inhibitory action on platelet adhesion. These observation provably suggest the relationship between acid glycosaminoglycans in the vascular endotherium and platelets.