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OBJECTIVE To examine the role of central mechanisms on the production and release of an ouabain-like factor, the effects of intracerebroventricular injections of 6-hydroxydopamine on the tissue content and on the plasma level of the ouabain-like factor were determined in rats. METHODS The vehicle (0.1% ascorbic acid in 0.9% saline) and 6- hydroxydopamine (250 micrograms/rat) were injected into the left lateral ventricle in ether-anaesthetized Wistar rats. Hypothalamus, pituitary, adrenal and venous blood was sampled 24h and 7 days later. The procedure was repeated using another rat group 7 days later. Characteristics of immunoreactive ouabain-like factor were determined by a combination of high-performance liquid chromatography and a highly sensitive enzyme-linked immunosorbent assay for ouabain. The level of the ouabain-like factor in these tissues and in plasma extracts measured by the enzyme-linked immunosorbent assay was compared between the two groups receiving 6-hydroxydopamine and the vehicle. RESULTS Twenty-four hours after the intracerebroventricular injections of 6-hydroxydopamine, the ouabain-like factor level in the pituitary, hypothalamus and plasma had decreased significantly, whereas the ouabain-like factor level in the adrenal had not changed. The content of noradrenaline in the hypothalamus was also decreased markedly 7 days later and the content of ouabain-like factor in the pituitary remained low. On liquid chromatography the elution pattern of the ouabain-like factor in plasma and in tissue extracts coincided with that of authentic ouabain. CONCLUSIONS Intracerebroventricular treatments with 6-hydroxydopamine elicited decreases in ouabain-like factor contents in the pituitary, the hypothalamus and the plasma. These results suggest that the production and release of ouabain-like factor are closely associated with the brain, particularly the hypothalamus-pituitary axis, and that noradrenergic or dopaminergic neurons, or both, play a key role in this mechanism.

Microflora from root canals and periodontal pockets of periodontally affected teeth were compared in order to elucidate the as yet unknown relationship between pulpal and periodontal disease. Caries-free teeth affected with advanced periodontitis and diagnosed as clinically dead by electric pulp testing were selected. The root canals and periodontal pockets were sampled, and the bacterial flora examined by both culture and interference microscopy. The results indicated that the aerobe/anaerobe ratio in the periodontal pocket was 0.23, while it was 0.0022 in the root canal, the large predominance of obligate anaerobes reflecting the anaerobic environment found in the root canal. Morphological classification obtained from interference microscopy showed similar proportions of morphotypes in the two sites. Results of anaerobic culture demonstrated a significantly higher rate of detection of facultative Streptococcus bacteria in the periodontal pocket than in the root canal. The predominant bacterial species common to both regions were Streptococcus, Peptostreptococcus, Eubacterium, Bacteroides, and Fusobacterium for obligate anaerobes. As for facultative anaerobes, Actinomyces and Streptococcus were detected predominantly in the periodontal pocket. The occurrence of micro-organisms common to both sites in this study suggests that the periodontal pocket may be a possible source of root canal infections.

X線写真による肺癌集検をより効果的にするため, 昭和60年度の宮城方式におけるX線写真による成績を分析した.スクリーニングにおける間接写真経年ファイルの導入は, 精度向上と効率化を可能としえた.受診者223796名より56例の肺癌を発見した.切除を行った37例のうち26例がStage Iaであった.腫瘤状陰影を呈した44例の腫瘍陰影径の平均は29mmであり, 30mm以下の症例は30例 (68%) であった.肺癌集検歴のある症例40例中28例に過去の集検写真で腫瘍陰影を認めた.過去の集検写真に腫瘍陰影を認める症例は, 認めない症例に比較し, 腫瘍陰影径が小さく病期が良好な傾向があった.

メインテナンス中の成人性歯周炎患者の158部位の歯肉縁下細菌叢および162部位の臨床指標を検索し, その変動から歯周ポケットの深さを予測することを多変量解析法を用いて行った。その結果, 重回帰分析の結果からは被検部位の歯周ポケットの深さの変動の約47.4%が運動性細菌の比率, 嫌気性グラム陰性桿菌の比率, 嫌気総菌数の3つの因子で説明できることが示された。また数量化理論I類の分析結果からは被検部位の歯周ポケットの深さの変動の約49.5%がplaque index, bleeding on probing, suppurative indexの3つの因子で説明できることが示された。さらにグラム陰性桿菌の比率とbleeding on probingがperiodontal disease activityの指標となる可能性が示唆された。

4～8mmの歯周ポケットを有する9名め成人性歯周炎罹患者について, プラークコントロール, 歯石除去及びルートプレーニングを施した。その前後にポケット底部より採取した細菌叢の変動を, グラム染色, 暗視野顕微鏡, 嫌気培養法を用いて検討した。その結果, 歯周初期治療後にグラム陽性球菌の増加とグラム陰性桿菌, 糸状菌の減少が認められた。また, 術前, プラークコントロール, 歯石除去とルートプレーニングの3時期において Fusobacterium 属は6.8%, 4.8%, 1.4%, Bacteroides 属は11.0%, 3.1%, 0.4%, Spirochetes は11.0%, 9.5%, 0.5%の変動を示した。black pigmented Bacteroides は7被検部位中3部位で, Fusobacterium necrophorum は7被検部位中5部位で検出された。Bacteroides はポケットの深さと, Spirochetes はポケットの深さ, 歯肉炎指数, プラークスコアとの間で各々有意な相関性が認められた。

γ-Methyl-substituted allylic ethers proved to be converted into β-substituted dienes exclusively on treatment with t-BuOK in refluxing THF or cyclohexane.

Background Platelet-rich fibrin (PRF), a platelet-rich plasma (PRP) derivative mainly composed of fibrin networks, has been increasingly demonstrated to be effective in wound healing in clinical and pre-clinical animal studies. However, there has still been a concern that major growth factors may significantly be loss from PRF during its preparation through the slow clotting process. To address this concern, we compared the angiogenic potential of PRF and PRP by standardization of procedures based on volume ratios. Methods PRP, PRF, and platelet-poor plasma (PPP) were prepared from the peripheral blood of healthy donors. PRF preparations were squeezed or homogenized to produce exudate (PRFexu) or extract (PRFext), respectively. Concentrations of the angiogenic factors and their bioactivities were determined using ELISA kits, a scratch assay using endothelial cells and a chicken chorioallantoic membrane (CAM) assay. Results In PRP and PRF preparations, both VEGF and PDGF-BB were significantly more concentrated than PPP. In the scratch assay, PRFexu and PRFext were the most effective for wound closure. In the CAM assay, PRF membranes were the most effective for neovascularization. Conclusions It is suggested that PRF preparations efficiently preserve the angiogenic factors and function not only as a scaffolding material but as a reservoir of angiogenic factors in wound healing.