Use of a micromanipulator system (NeuRobot) in endoscopic neurosurgery.

NeuRobot, a micromanipulator system with a rigid neuroendoscope and three micromanipulators, was developed for less invasive and telecontrolled neurosurgery. This system can be used to perform sophisticated surgical procedures through a small, 10-mm-diameter, window. The present study was performed to evaluate the feasibility of using NeuRobot in neuroendoscopy. Four different intraventricular neurosurgical procedures were simulated in three fixed cadaver heads using NeuRobot: (1) fenestration of the floor of the third ventricle; (2) fenestration of the septum pellucidum; (3) biopsy of the thalamus; and (4) biopsy of the choroid plexus of the lateral ventricle. Each procedure required less than 2 min, and all procedures were performed accurately. After these surgical simulations, a third ventriculostomy was carried out safely and adequately in a patient with obstructive hydrocephalus due to a midbrain venous angioma. Our results confirmed that NeuRobot is applicable to lesions in which conventional endoscopic neurosurgery is indicated. Furthermore, NeuRobot can perform more complex surgical procedures than a conventional neuroendoscope because of its maneuverability and stability. NeuRobot will become a useful neurosurgical tool for dealing with lesions that are difficult to treat by conventional neuroendoscopic surgery.

Bianthraquinones from Cassia siamea.

The isolation of two bianthraquinones, 1,1',3,8,8'-pentahydroxy-3',6-dimethyl[2,2'-bianthracene]-9,9',10,10'-tetrone and 7-chloro-1,1',6,8,8'-pentahydroxy-3,3'-dimethyl[2,2'-bianthracene]-9,9',10,10'-tetrone, from the root bark of Cassia siamea is reported. The structures were established by analysis of spectroscopic data and 7-chloro-1,1',6,8,8'-pentahydroxy-3,3'-dimethyl[2,2'-bianthracene]-9,9',10,10'-tetrone was determined on the direct comparison with synthetic compound.

Cyclopentene dialdehydes from Tabebuia impetiginosa.

The isolation of two cyclopentene dialdehydes, 2-formyl-5-(4'-methoxybenzoyloxy)-3-methyl-2-cyclopentene-1-acetal dehyde, and 2-formyl-5-(3', 4'-dimethoxybenzoyloxy)-3-methyl-2-cyclopentene-1-acetaldehyde, from the bark of Tabebuia impetiginosa is reported. The structures were established by analysis of spectroscopic data. These compounds showed anti-inflammatory activity.

[The influence of methionine and its metabolites on the progression of atherosclerosis in rabbits].

The effects of a high level of methionine on the changes of lipid and amino acid metabolism were investigated. Eighteen New Zealand White rabbits were divided into three groups; a methionine group, which was fed a diet supplemented with 3% D, L-methionine, a Cholesterol+Methionine group, which was fed a 3% D, L-methionine and a 0.2% cholesterol diet, and a Cholesterol group which was fed a 0.2% cholesterol diet for 22 weeks. The plasma triglyceride, cholesterol, homocysteine, cysteine and serum SO4(2-) levels were measured and compared. On the first and the final day of the experiment, lipid peroxide levels in blood samples were also measured. We found that the Methionine group and the Cholesterol+Methionine group showed elevated levels of plasma triglyceride, cholesterol, homocysteine, cysteine, serum SO4(2-) and lipid peroxide compared with the Cholesterol group. More prominent fat deposits in the aorta were observed in the Methionine group and the Cholesterol+Methionine group than in the Cholesterol group. Our results indicated that the interaction of cholesterol with methionine or its derivatives plays a role in the progression of atherosclerosis.

Functional assessment of the stratum corneum under the influence of oral aromatic retinoid (etretinate) in guinea-pigs and humans. Comparison with topical retinoic acid treatment.

Clinically we have noted that the skin of patients treated with long-term oral etretinate becomes uniformly soft and smooth to touch, like facial skin that becomes smoother and less wrinkled following treatment with topical tretinoin. This suggests that retinoids, whether used systemically or topically, alter the physical properties of the skin, particularly of the stratum corneum (SC). To study the influence of retinoids on the SC, we serially assessed the functional properties of the SC non-invasively in retinoid-treated humans and experimental animals. SC hydration and barrier function were assessed by measurement of high-frequency conductance and transepidermal water loss (TEWL), respectively. Daily application of topical retinoic acid creams was found to rapidly induce a time- and dose-dependent, linear increase in SC hydration of the forearm skin of healthy adults over a 2-week period and to compromise its water barrier function in a similar fashion. Systemic administration of high-dosage etretinate, 4 or 8 mg/kg/day, to guinea-pigs also induced dose-dependent increases in both SC hydration and TEWL measured on the plantar skin after 1 month. Moreover, in the animals given etretinate 4 mg/kg/day we confirmed a slight but significant decrease in the number of cell layers of the plantar SC. Likewise, patients with various dermatoses began to show similar functional changes of the SC in the uninvolved skin of the flexor surface of the forearms 3 weeks after the start of oral etretinate treatment, consisting of 50 mg daily for 2 weeks, followed by gradual dose tapering.(ABSTRACT TRUNCATED AT 250 WORDS)

A Chinese traditional medicine, juzentaihoto, inhibits the O2- generation by macrophages.

Guinea pig peritoneal macrophages generate superoxide anion (O2-), when stimulated with N-formyl-L-methionyl-L-leucyl-L-phenylalanine (fMLP), phorbol-myristate acetate (PMA) or ovalbumin complex of guinea pig IgG2 antibody (OA gamma 2). These responses were found to be inhibited by a Chinese traditional medicine, Juzentaihoto (JT). When the inhibition was assayed by the use of fMLP as a stimulant, at least one of the substances responsible for the inhibitory activity of JT was identified to be cinnamic acid. An authentic sample of cinnamic acid also inhibited the O2- generation by fMLP-stimulated macrophages. Cinnamic acid, however, did not inhibit the O2- generation, when macrophages were stimulated with PMA and OA gamma 2. These results indicate that a certain cinnamic acid-inhibitable factor may be involved in the intracellular triggering event(s) initiated by fMLP, leading to activation of the respiratory burst reduced nicotinamide adenine dinucleotide phosphate oxidase, but not in those by PMA and OA gamma 2.