Involvement of the Central Catecholaminergic System in Nicotine-Induced Tail-Tremor in Rats

The effect of 6-hydroxydopamine on repeated nicotine-induced tail-tremor was investigated in rats. Tail-tremor induced by nicotine (0.5 mg/kg/day, subcutaneously) became more pronounced in intensity with daily administration for 9 days. Rats pretreated with 6-hydroxydopamine (250 micrograms, intracerebroventricularly) showed almost the maximum degree of tail-tremor during the whole experimental period. However, in rats pretreated with 6-hydroxydopamine plus desipramine, enhancement of tail-tremor was slight in the beginning but increased with the daily nicotine administration. Fourteen-day administration of nicotine did not result in significant changes in noradrenaline and dopamine levels in the cortex, hypothalamus, striatum and nucleus accumbens. These results suggest that nicotine-induced tail-tremor is associated with the supersensitivity of postsynaptic catecholaminergic receptors in the central nervous system, and that the noradrenergic system may be more important than the dopaminergic system in this phenomenon.</p

Repeated Mazindol and Methamphetamine Administration Produces Cross-Sensitization to Stereotyped Behavior Induced by these Agents in Rats

The cross-sensitization to stereotyped behavior between mazindol (MZD) and methamphetamine (MAP) was investigated in rats. MZD (5 and 10 mg/kg/day, p.o.), MAP (5 and 10 mg/kg/day, p.o.) and saline (1 ml/kg, p.o.) were administered once daily for a week. Challenge with MZD (10 mg/kg, p.o.) on the 8th day caused markedly stereotyped behavior in MAP-pretreated group compared with the saline-pretreated control group. MAP (10 mg/kg, p.o.)-induced stereotyped behavior on the 8th day was also greater in MZD-pretreated group rather than the saline-pretreated control group. These results suggest that repeated MZD and MAP administration cross-sensitizes to their stereotype-producing effects.</p

Analysis of hydroxy sphingomyelin

Sphingomyelin (SM) with N-α-hydroxy fatty acyl residues (hSM) has been shown to occur in mammalian skin and digestive epithelia. However, the metabolism and physiological relevance of this characteristic SM species have not been fully elucidated yet. Here, we show methods for mass spectrometric characterization and quantification of hSM. The hSM in mouse skin was isolated by TLC. The hydroxy hexadecanoyl residue was confirmed by electron impact ionization-induced fragmentation in gas chromatography-mass spectrometry. Mass shift analysis of acetylated hSM by time of flight mass spectrometry revealed the number of hydroxyl groups in the molecule. After correcting the difference in detection efficacy, hSM in mouse skin and intestinal mucosa were quantified by liquid chromatography-tandem mass spectrometry, and found to be 16.5 ± 2.0 and 0.8 ± 0.4 nmol/μmol phospholipid, respectively. The methods described here are applicable to biological experiments on hSM in epithelia of the body surface and digestive tract

Transphosphatidylation by GIPC-PLD

Glycosylinositol phosphoceramide (GIPC) is the most abundant sphingolipid in plants and fungi. Recently, we detected GIPC-specific phospholipase D (GIPC-PLD) activity in plants. Here, we found that GIPC-PLD activity in young cabbage leaves catalyzes transphosphatidylation. The available alcohol for this reaction is a primary alcohol with a chain length below C4. Neither secondary alcohol, tertiary alcohol, choline, serine nor glycerol serves as an acceptor for transphosphatidylation of GIPC-PLD. We also found that cabbage GIPC-PLD prefers GIPC containing two sugars. Neither inositol phosphoceramide, mannosylinositol phosphoceramide nor GIPC with three sugar chains served as substrate. GIPC-PLD will become a useful catalyst for modification of polar head group of sphingophospholipid

Terrestrial biota of Nishinoshima Island, the Ogasawara Islands, in 2021

西之島は2019年12月から2020年8月までの噴火により全域が溶岩と火山灰に被覆され、旧西之島由来の陸地のない完全な新島と言える状況となった。この島の陸上生物相の現状把握のため、2021年7月と9月に調査を行った。無人航空機による調査の結果、カツオドリ、アオツラカツオドリ、クロアジサシ、セグロアジサシ、オオアジサシの繁殖が確認された。陸上に設置した自動録音装置ではオナガミズナギドリの飛来が確認された。上陸地探索で上陸した北部の海岸ではカツオドリの死体は分解が進んでいなかったものの、死体下の砂礫からノミバエ類の蛹が確認されたほか、消化管内からハマゴウの種子が検出された。このほか菌類らしき構造が確認されたが、植物は確認されなかった。海鳥の繁殖成功度は低く、現在の西之島はエコロジカルトラップになっている可能性がある。海鳥は重要な生態系機能を持ち生態系成立プロセスに大きな影響を与えるため、初期の鳥類相変化のモニタリングが不可欠である。The eruption from December 2019 to August 2020 had covered the entire area of Nishinoshima with lava and volcanic ash, making it a completely new island without land derived from the former Nishinoshima. In order to clarify the current status of the terrestrial biota on this island, we conducted surveys in July and September 2021. As a result of the survey using unmanned aerial vehicles, we confirmed the breeding of the brown booby, masked booby, brown noddy, sooty tern and great-crested tern. The arrival of the wedgetailed shearwater was confirmed by using acoustic recorders located on the island. The carcass of a brown booby found on the northern beach had not decomposed, but pupae of Phoridae fly were identified in the sand under the carcass, and Vitex rotundifolia seeds were found in the digestive tract of the carcass. In addition, fungus-like structures were observed, but no plants were found. The breeding success of seabirds seemed very low, and Nishinoshima might be an ecological trap. Since seabirds have important ecological functions and greatly influence the process of ecosystem establishment of Nishinoshima, it is essential to monitor the initial avifaunal changes.departmental bulletin pape

Steady-state serum concentrations of carbamazepine and valproic acid in obese and lean patients with epilepsy.

Steady-state serum concentrations of carbamazepine (CBZ) and valproic acid (VPA) were investigated in normal weight (body mass index; BMI 20 to 25), lean (smaller than 20 BMI) and moderately obese subjects (greater than 25 BMI) who received either 400 mg/day of CBZ or 800 mg/day of VPA. The CBZ serum concentration in lean subjects was significantly higher than that in normal weight subjects. However, no significant differences in VPA serum concentration were found between the three groups. The CBZ serum concentration decreased with increases in total body weight, and the VPA serum concentration decreased with increases in ideal body weight. However, both serum concentrations were not correlated with BMI. These results suggest that VPA doses should be calculated using ideal body weight and that degree of obesity may affect CBZ serum concentration rather than VPA serum concentration.</p

Continuous in-vIvo measurement of the brain tissue and the ischemic muscle gas tension using MEDSPECT, MS-8

I MEDSPECT is a medical mass spectrometer for continuous in-vivo measurement of tissue, blood and respiratory gases. Interfacing catheter for tissue in measurement has Teflon membrane. The permeability and perfusion rate for various gases through its membrane varied with temperature. The temperature coefficient of Teflon catheter in the range of 15℃-40℃ is approximately constant with -2% of correction per degree for oxygen and carbon dioxide. Linear correlation was confirmed experimentally. II The brain tissue gas tensions were measured in ten dogs with intra-venous anesthesia at normothermia and deep hypothermia using perfusion cooling, including circulatory arrest for 30 minutes at 20°C of cerebral temperature. On average, the brain tissue P(O2) was 15mmHg in normothermia when the arterial P(O2) showed 95mmHg and the brain tissue P(CO2) was 49mmHg when the arterial PC02 showed 30mmHg. The brain tissue carbon dioxide tension gradually decreased by cooling and increased during circulatory arrest for 30 minutes; from 45mmHg to 72mmHg. The brain tissue oxygen tension increased during cooling from 15mmHg to 41mmHg and decreased in the circulatory arrest; from 41mmHg to 36mmHg. III The ischemic muscle gas tension was measured in a 22-year-old man, who was suffered from thromboangiitis obliterans bilaterally, and had the popliteal autovein bypass surgery 3 months ago. Control oxygen tensions in the both anterior tibial muscles showed about the same; 35mmHg and 36mmHg respectivelly, and the P(O2) of the non-operated side showed remarkable low level of 18mmHg as compared with the side of arterial reconstruction surgery after 5-minutes ankle exercise

Molecular Pathological Characteristics of Thyroid Follicular-Patterned Tumors Showing Nodule-in-Nodule Appearance with Poorly Differentiated Component

Thyroid follicular-patterned tumors (TFTs) showing nodule-in-nodule (NN) appearance with poorly differentiated component (PDc) but neither invasion nor metastasis are diagnosed as benign nodules. Although PDc exhibits histologically aggressive features relative to the outer nodule (Out-N), its pathological significance remains unclear. TP53 binding protein-1 (53BP1) is a DNA damage response (DDR) molecule that rapidly localizes at DNA double-strand breaks. Using dualcolor immunofluorescence with Ki-67, the profile of 53BP1 expression is shown to be significantly altered during diverse tumorigenesis. In this study, we aimed to elucidate the malignant potential of PDc at the molecular level. We analyzed the profile of 53BP1 expression and NRAS codon 61 and TERT-promoter (TERT-p) mutations in 16 cases of TFTs showing NN with PDc compared to 30 adenomatous goiters, 31 follicular adenomas, 15 minimally invasive follicular carcinomas (FCs), and 11 widely invasive FC cases. Our results revealed that the expression level of abnormal type 53BP1 and incidence of NRAS and TERT-p mutations in PDc were comparable to FCs, suggesting a malignant potential. Because co-expression of 53BP1 and Ki-67 can be an indicator of altered DDR, the development of PDc in NN may be associated with DDR impairments after harboring NRAS and TERT-p mutations

UAV-based exploratory survey of invertebrates on Nishinoshima Island

西之島は2013年以降断続的に噴火を繰り返しており、2017年からは毎年噴火が記録されている。特に2019年12月からの激しい噴火以降は火山活動への警戒により、島のほぼ全てのエリアで上陸調査ができない状況が続いている。しかし、その期間中も西之島では生態系遷移が進むと考えられる。そこで無人航空機（UAV）を活用することにより、遠隔からの生態系モニタリングを実施することとした。小型の無脊椎動物については撮影調査による情報収集が難しいことから、粘着トラップ、吸引機、採水器をUAV で運搬して試料を採集する新規の手法により調査を試みた。粘着トラップではカクレイワガニとシラミバエの1種が捕獲され、採水サンプルの環境DNA解析では軟体動物、棘皮動物のDNA が検出された。生態系遷移の初期段階を明らかにするための調査においては網羅的な生物群の時間的変化を記録することが重要である。火山活動が続く西之島において安全に生態系モニタリングを継続するためにUAVを活用した多様な生物の探索技術は重要な手段となりうる。Nishinoshima Island has been volcanically active since 2013, with eruptions recorded every year since 2017. Especially since the severe eruption in December 2019, almost all areas of the island cannot be surveyed ashore due to the warnings of volcanic activity. However, ecological succession on Nishinoshima Island may continue to progress even during the period. We utilised UAVs to carry out remote ecosystem monitoring. As it is difficult to collect information on small invertebrates by photographing surveys, we tried new methods for collecting samples by transporting a sticky trap, a vacuum cleaner and a water sampler using a UAV. Geograpsus grayi and Olfersia sp. were captured in the sticky traps. Environmental DNA analysis of the collected water samples detected molluscs and echinoderms. It is important to record temporal changes of a comprehensive biological dataset in order to clarify the earliest stages of ecosystem succession on oceanic islands. Various biological survey techniques using UAVs can be important tools for safely conducting continuous implementation of ecosystem monitoring on Nishinoshima Island, where volcanic activity is continuing.departmental bulletin pape