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Similar to psychostimulants, the peripheral administration of menthol promotes mouse motor activity, and the neurotransmitter dopamine has been suggested to be involved in this effect. The present study aimed to elucidate the effects of l-menthol on parts of the central nervous system that are involved in motor effects. The subcutaneous administration of l-menthol significantly increased the number of c-Fos-like immunoreactive nuclei in the dorsal striatum of the mice, and motor activity was promoted. It also increased the extracellular dopamine level in the dorsal striatum of the mice. These observations indicated that after subcutaneous administration, l-menthol enhances dopamine-mediated neurotransmission, and activates neuronal activity in the dorsal striatum, thereby promoting motor activity in mice.

Permeability and thermal conductivity of natural gas hydrate sediments were characterized using a microfocus X-ray computed tomography (CT) technique. The free-gas spaces, sand particles, and hydrates or ices were identified from the obtained three-dimensional X-ray CT images, from which continuous pore networks were identified. The absolute permeability of the sediment correlated well increased with the ratio of parallel to vertical directions of continuous pore numbers. This fact indicates that the pore network in sediment can be useful for assessment of permeability. In order to characterize the thermal conductivity of methane hydrate sediments, a homogenization method was applied to microfocus X-ray CT images. The thermal conductivity calculated from three dimensional X-ray CT images was good agreement to those measured by the hot disk method, when the thermal conductivity of sand particles is 0.5 W/mK. These results demonstrated that the microfocus X-ray CT imaging can be effective for studying material flow and thermo-mechanical properties of natural gas hydrate sediments.

Excretory dysfunction associated with congenital anal anomalies (a generic term that includes anal atresia and Hirschsprung's disease) is presumed to greatly affect the psychology of the affected children. In this study, we conducted a survey on the psychological status of children with excretory dysfunction, and investigated the relationship between the affected children and their families in addition to their social life. Four children with fecal dysfunction due to a congenital anal anomaly and their mothers were interviewed. The results of psychological tests in the children and mothers along with our findings in the interviews with the children and mothers, were included in the data analysis. We found that regardless of the degree of excretory dysfunction, the child's state of mind was influenced by whether the mother exhibited warmth or criticism towards her child and whether there was a support system for the mother and child. We suggest that psychiatric consultation is necessary for these children.

We report that tissue-like structure can be formed when cells are cultured on a microporous polymer film (honeycomb film). The honeycomb films were fabricated by applying a moist air to a spread polymer solution containing biodegradable polymers (poly(L-lactic acid) (PLLA) and poly(ε-caprolactone) (PCL)) and an amphiphilic polymer. Hepatocytes were cultured on a self-supporting honeycomb film of PLLA. The hepatocytes formed a single layer of columnar shape cells with a thickness of 20 μm. The tissue formation of hepatocytes was specifically occurred on the honeycomb film of PLLA and not on a flat film of PLLA. Three-dimensional tissue structures were formed, when cells were cultured on both sides of the self-supporting honeycomb film. Double layers of hepatocytes were obtained by the method. Striated tissues such as heart and blood vessel could be reconstructed by utilizing a stretched honeycomb film of PCL.

マンガン酸化バクテリアの媒介によってマンガン酸化物が沈殿している東海大学海洋科学博物館の地下海水給水系に, スライド・ガラスを多数設置し, その上に付着するマンガン酸化バクテリアおよび酸化物を時系列的に調べ, マンガン酸化物の成長過程の形態学的および化学的研究を行った。最初, バクテリアがばらばらにスライドガラスに付着し, その後集菌する。それらは集塊状になった後溶菌する。溶菌と共にマンガン酸化物が沈殿を開始し, ドーナツ状, ドーム状を経て, カリフラワー状に成長する。ドーナツ状になった段階で, 酸化物表面に, マンガン酸塩(manganate)特有の蜂の巣状構造が現れる。マンガン酸化物の成長速度は1.8×10-2mmyr-1であり, Mn(II)の酸化速度定数(kMn)は, kMn=6×1019mol-4l4d-1であった。マンガン酸化物中のCoおよびNiの濃度は, 沈殿後取り込み現象(post-depositional uptake)により, 時間と共に増加するが, Cuにはこの傾向は見られなかった。

海水(Mn~2+:約50ppm;pH:約8.0)中でバクテリアの媒介によって生成するマンガン酸化物鉱物を, いろいろなマンガン酸化バクテリアと海水の組み合わせを用いて調べた。その結果, hydrohausmannite, feitknechtite(β-MnOOH), manganite(γ-MnOOH), unnamed MnO2 mineral(JCPDS Card:42-1316)および10Å manganate(buseriteあるいはtodorokite)が生成したが, マンガン酸化物が生成しない組み合わせもかなり存在した。バクテリアのマンガン酸化活性が高いときには, 酸化状態の高いMn(IV)酸化物が, それが低いときには, Mn(III)酸化物が, それぞれ生成した。各鉱物は, 中間物質を経ることなく, Mn~2+の酸化によって直接生成したものと考えられる。海洋環境に存在するMn(IV)酸化物は, 純粋な無機的反応よりもむしろ微生物の媒介によって生成するものと考えられる。

The tensile bond strength (TBS) to denture base materials of silicone-rubber soft relining materials (DRS: Denture Relining Soft type, GC) immersed in water at 37°C from 1 day to 8 weeks was investigated. Four denture base metals (18 K-Au alloy, Ag-Pd-Au alloy, Co-Cr alloy and Pure Ti) and two denture base resins (polycarbonate resin and polysulfon resin) were used. The TBS of DRS was 1.39-2.05 MPa to denture base metals and 1.59-1.81 MPa to denture base resin after 1-dayimmersion, and 1.59-2.75 MPa and 1.47-2.33 MPa respectively after 8-week immersion. These values were significantly superior to those of two ordinary silicone-rubber relining materials.

In order to utilize sarcotestae of Ginkgo biloba for medical purposes, their flavonoids and terpenoids were qualitatively and quantitatively analyzed. Flavonols such as kaempferol, quercetin and isorhamnetin present in leaves could not be detected in sarcotestae while anthocyanidins of delphinidin and cyanidin were found. Sarcotestae were noted to contain small amounts of ginkgolides A, B and C as terpenoids, as did also the leaves. The composition of ginkgolides in sarcotestae were varied during maturation whereas quantity of anthocyanidins was independent on harvest season.

To determine whether chronic central gamma-aminobutyric acid (GABA) stimulation would attenuate development of hypertension, tail-cuff systolic pressures were measured in male spontaneously hypertensive rats (SHR) treated with either an inhibitor of GABA breakdown (valproate, VPA), or a GABA-receptor agonist (muscimol). When VPA was injected intraperitoneally (i.p.) daily for 4 weeks, tail-cuff systolic pressures were decreased during the last 2 weeks. On the other hand, continuous infusion of muscimol into the lateral cerebral ventricle for 14 days using an osmotic minipump decreased systolic pressures throughout the 10-day observation period. During terminal experiments under urethane anesthesia, pressor and sympathetic nerve responses to electrical stimulation of the ventromedial hypothalamus were reduced in VPA- or muscimol-treated SHR. Pressor responses to intravenously (i.v.) injected norepinephrine (NE) were unaltered by either treatment, indicating that diminished pressor responsiveness to hypothalamic stimulation was not due to diminished cardiovascular reactivity. Regardless of either VPA acid or muscimol treatment, basal blood pressure (BP), heart rate (HR), and responses to hypothalamic stimulation were lower in normotensive Wistar-Kyoto controls (WKY) than in SHR. In addition, chronic treatment with either drug had weaker hypotensive and hypothalamic depressant effects in WKY than in SHR. Our results suggest that in SHR the central GABAergic system is impaired and that chronic treatment with GABAergic stimulants can attenuate development of spontaneous hypertension by reducing hypothalamic overactivity.

A 59 year-old housewife was admitted to the emergency service with a sudden onset of chest pain and nausea. Initially she was treated as an acute myocardial infarction, but conventional treatments were not effective, and she was sent to our hospital for further evaluation. Her ECG showed several abnormal findings including T-wave inversion, atrial flutter, QT-time prolongation, ST-segment depression or elevation, and frequent ventricular ectopic beats. The echocardiogram, 201thallium scintigram and coronary angiography were almost normal. Both urinary and plasma levels of catecholamines were remarkably increased, and the plasma epinephrine was extremely high during attacks. Abdominal echotomography and CT-scanning showed a large left adrenal tumor. The 131MIBG scintiscan revealed a high accumulation in this tumor. Then the patient was diagnosed as having pheochromocytoma and catecholamine-induced myocarditis. The administration of phentolamine (10 mg) normalized the inversion of T-wave and the high blood pressure. But when propranolol (2 mg) was administrated in addition to phentolamine, the ECG showed a biphasic low T-wave change. According to these phenomena, we supposed that the alpha-adrenergic receptor was involved in the development of the ST-T changes of the ECG, and the alpha-adrenergic receptor of this patient might be sensitive under excessive catecholamines, according to the inhibition of the beta-receptor by propranolol.

From biological and clinical perspectives, it is important to clarify tumor heterogeneity. This study was aimed to investigate whether or not intratumoral heterogeneity of DNA ploidy pattern exists in hepatocellular carcinoma (HCC).Using fresh materials resected from 31 untreated patients, DNA ploidy was analyzed at different sites of the same HCC by means of flow cytometry. The tumor size ranged from 1.7 to 25.0 cm.There was no case in which euploid and aneuploid HCCs coexisted in the same tumor. The DNA ploidy pattern was euploid in 15 and aneuploid in 16 instances. Of 15 euploid tumors, the areas analyzed were all diploid in 12 and tetraploid in 2 but diploid/tetraploid in 1. Among 16 aneuploid tumors, the DNA indices (DI) at different sites were similar in 9, but apparently, different aneuploid subclones coexisted in 7 cases. The incidence of DI heterogeneity in aneuploid HCCs was similar between small (5 cm) and large (or = 5 cm) tumors; 3 of 7 (42.9%) versus 4 of 9 (44.4%).It is assumed that euploid and aneuploid HCCs develop in their own ploidy pattern and that the evolution of aneuploid subpopulations from euploid HCC is rare, but new aneuploid subclones can evolve from aneuploid HCC due to increased instability of its karyotype.

To determine whether clonidine can improve the central alteration of the baroreflex in SHR, the centrally cut end of the aortic depressor nerve was electrically stimulated in SHR with intravenously administered clonidine. Aortic depressor nerve (ADN) stimulation elicited depressor and sympatho-inhibitory responses in a frequency-dependent manner in WKY and SHR. These responses were significantly smaller in SHR than in WKY. The attenuated depressor and sympatho-inhibitory responses to ADN stimulation in SHR were restored following i.v. injections of clonidine, although the drug did not affect the responses to ADN stimulations in WKY. These findings suggest that clonidine can improve central attenuation of the baroreflex in hypertension.

This study aimed to elucidate the mechanism of the hypotensive effect of bromocriptine (BRC), and to investigate whether or not the effects of BRC on the sympathetic nervous system are altered in hypertension. BRC was administered intravenously to normotensive and spontaneously hypertensive rats (SHR). It elicited hypotensive effects dose-dependently in urethane-anaesthetized normotensive rats, an effect which was antagonized with metoclopramide. Pretreatment with intravenous hexamethonium attenuated the hypotensive effect of BRC. BRC decreased plasma norepinephrine (NE) without inhibiting the sympathetic nerve spikes recorded from the postganglionic sympathetic nerve bundle. The hypotensive effect of BRC was significantly greater in SHR than in Wistar Kyoto Rats (WKY). Decrease in NE by BRC was also significantly greater in SHR than in WKY. These results suggest that the hypotensive effect of BRC is induced by suppression of NE release, not by inhibition of sympathetic nerve spikes, and that the dopaminergic presynaptic inhibition is attenuated in SHR.

The hypothesis that a functional projection from the locus coeruleus (LC) to the posterior hypothalamus contributes to the development of hypertension in SHR, was tested by measuring norepinephrine (NE) in the posterior hypothalamus by brain dialysis after injections of L-glutamate (L-glu) into LC. L-glu elicited a prolonged elevation of blood pressure in both SHR and WKY. Pressor effects were significantly larger in SHR than in WKY. Extracellular NE in the posterior hypothalamus increased after LC stimulation; NE release was significantly higher in SHR than in WKY. Injections of 6-hydroxydopamine (6-OHDA) into posterior hypothalamus lowered the resting blood pressure and attenuated the pressor responses to L-glu injections into the LC in SHR. These findings suggest that the LC projects functionally to the posterior hypothalamus and that the projection can contribute to the development of hypertension in SHR.

An experiment was conducted with growing rats to investigate the effects of feeding excessive specific L-amino acids for 8 days on serum and tissue cholesterol, alpha-tocopherol, ascorbic acid, and copper, and on liver microsomal cytochrome P-450. To a 10% casein diet were added 4% L-methionine, 5% L-cystine, 5% L-histidine, 5% L-threonine, 5% L-tryptophan, 5% L-phenylalanine, 5% L-tyrosine, 6% L-valine, 7% L-isoleucine, 7% L-lysine, or 8% L-leucine. Excessive cystine and histidine increased serum cholesterol and alpha-tocopherol. Excessive cystine and methionine increased liver and kidney alpha-tocopherol and ascorbic acid. Excessive tyrosine and phenylalanine caused a marked increase in serum copper and ceruloplasmin activity, whereas excessive cystine, methionine, and histidine caused a decrease in the ceruloplasmin activity. Excessive histidine increased liver cytochrome P-450, whereas excessive tyrosine markedly decreased liver cytochrome P-450.

甘藷デンプン粒は, 20℃, 5M尿素で膨潤および溶解が始まり,尿素濃度が高くなるにつれて,膨潤およびデンプンの溶解度が増大した。 10M尿素では約13%のデンプンが可溶化された。尿素処理したデンプンのプルラナーゼによる分解可溶化は,デンプンの尿素変性度合と相関関係は認められず,あるレベル以上の変性を受けると急速に進行した。10M尿素処理デンプンのプルラナーゼ処理で,約67%のデンプンが可溶化された。10M尿素-プルラナーゼ処理にも抵抗性のデンプンは約20%であった。デンプン粒は尿素により構造上の変性を受け, 7M以上の尿素で2～3倍に急速に膨潤した。膨潤デンプンはヨウ素により内層部は青色に,外層部は紫褐色になり,洗浄すると内層部のデンプンが溶出して,袋状の外層部からなるものに分画された。この袋状デンプンのプルラナーゼ処理により,デンプン粒の表層と考えられる殼が残査として得られた。

Tail-cuff systolic pressures became elevated in male Wistar rats fed chow containing 8% NaCl for 4 weeks. After 4 weeks of salt loading, pressor and sympathetic responses to ventromedial hypothalamic stimulation were larger in salt-loaded rats. When similar experiments were done following sinoaortic denervation, all of the effects previously induced by dietary salt loading persisted. By contrast, after only 1 week of salt loading, pressor and sympathetic responses to hypothalamic stimulation were reduced, instead of being increased. Since circulating plasma volume was increased in week 1, it was considered possible that reduced hypothalamic responsiveness was due to enhanced cardiopulmonary baroreflexes. Supporting this interpretation, bilateral vagotomy reversed the hypothalamic inhibition occurring in week 1. Although neither the site nor mechanism causing sympathetic hyperactivity has been determined, our results indicate that chronic dietary salt loading has biphasic effects on the ventromedial hypothalamus: an initial inhibition in the first week followed by stimulation thereafter. These results could mean that dietary salt loading eventually increases sympathetic activity and thereby induces hypertension by stimulating the ventromedial hypothalamus.

To determine whether the renal nerves affect central baroreflex regulation, the aortic depressor nerve (ADN) was stimulated electrically, while blood pressure, heart rate, and splanchnic nerve activity were recorded in renal denervated and sham-operated rats anesthetized with urethane. Tail cuff systolic pressure fell 6 days after renal denervation, but mean blood pressure recorded after anesthetizing with urethane did not differ between renal denervated and sham-operated rats. Urinary sodium excretion was greater in renal denervated than in sham-operated rats. ADN stimulation produced frequency-dependent falls in blood pressure accompanied by inhibitions of sympathetic nerve activity and heart rate. Depressor and sympathetic inhibitory responses to ADN stimulation were significantly smaller in renal denervated than in sham-operated rats. These findings suggest that the renal nerves can regulate baroreflexes centrally.

The authors devised a new method for making a maxillary prosthesis with a hollow obturator, which was named the Balloon Technique. This new technique has a number of advantages over the conventional method in that it not only facilitates the molding of a soft plastic hollow obturator in a single process, but also simplifies the trial fitting of the completed obturator. Furthermore, it makes possible firm adhesion of the hollow obturator and the denture base by the hot-melt method while the denture base resin is cured. Finally, the completed maxillary prosthesis is extremely light.