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.

A 21-aminosteroid, U-74006F, attenuates endotoxin-induced lung injury in awake sheep.

The purpose of the present study was to examine the efficacy of U-74006F, a 21-aminosteroid, on lung dysfunction induced by endotoxaemia in awake sheep with lung lymph fistula and haemodynamic monitoring. We measured pulmonary haemodynamics, lung lymph balance, circulating leucocyte count, arterial blood gas tensions, and levels of thromboxane (Tx) B2 and 6-keto-prostaglandin (PG) F1 alpha in plasma and lung lymph. We performed two experiments. In experiment 1 (n = 6), we intravenously infused Escherichia coli lipopolysaccharide endotoxin (1 microgram/kg) over 30 min and observed the parameters over 5 h. In experiment 2 (n = 6), we pretreated sheep with an intravenous bolus of U-74006F (2 mg/kg) 30 min before the infusion of endotoxin in the same manner of experiment 1, and continuously infused U-74006F (0.5 mg/kg per h) over 5 h after the bolus during the experiment. The U-74006F significantly suppressed the early pulmonary hypertension, the late increase in pulmonary permeability and the elevations of TxB2 and 6-keto-PGF1 alpha levels in plasma and lung lymph during the early period following endotoxaemia, although the compound did not change the time course of leucocytopenia and hypoxaemia. These findings suggest that the administration of U-74006F attenuates the lung dysfunction induced by endotoxaemia in awake sheep.

The effect of kampo formulae on bone resorption in vitro and in vivo. II. Detailed study of berberine.

We previously isolated berberine from aqueous extracts of tsu-kan-gan, a Kampo formula used for the treatment of osteoporosis. Berberine caused an inhibitory effect on parathyroid hormone (PTH)-stimulated bone resorption in neonatal mouse bone. In this report we describe the inhibitory effect of berberine on the formation of osteoclast-like multinucleated cells (OCLs) in the co-culture of mouse osteoblastic cells and bone marrow cells in the presence of 1alpha,25-dihydroxyvitamin D3 [1alpha,25(OH)2D3], PTH and interleukin-1alpha (IL-1alpha). Berberine dose-dependently inhibited the formation of tartrate-resistant acid phosphatase (TRAP)-positive OCLs induced by 1alpha25(OH)2D3, PTH and IL-1alpha. We prepared OCLs in the co-culture of osteoblastic cells and bone marrow cells. The effect of berberine on pit formation by OCLs was examined using dentin slices. As OCLs are terminally differentiated multinucleated cells, the survival of OCLs affects the bone-resorbing activity of OCLs. This prompted us to count the number of TRAP-positive OCLs on the slices. Berberine dose-dependently inhibited pit formation and caused a decrease in the number of TRAP-positive OCLs. Calcitonin (CT) inhibited pit formation without affecting the number of OCLs. Berberine accelerated the cell death in OCLs cultivated on a culture plate, but CT did not affect the cell death of OCLs. This suggests that the decrease in the number of OCLs on dentin slices may be due to apoptotic cell death in OCLs. In fact, Hoechst 33258 staining revealed that the treatment of OCLs with berberine resulted in condensed nuclei and a decrease in cell size. Oral administration of the berberine (30 and 50 mg/kg/d) to ovariectomized rats prevented a decrease in bone mineral density (BMD) of the lumbar vertebra without affecting the weight of the uterus and plasma concentration of estradiol. These results suggested that berberine prevented a decrease in BMD in vivo by inhibiting osteoclastic bone resorption.

Ion exchange chromatography of aluminum using 3-carboxy-2-naphthylamine-N,N-diacetic acid as a fluorescent post-column chelating reagent.

Ion exchange chromatography of aluminum ion using 3-carboxy-2-naphthylamine-N,N-diacetic acid (CNDA) as a fluorescent post-column chelating reagent was studied. The solution containing ammonium chloride and hydrochloric acid was used for the eluent, and acetate buffer solution containing CNDA was used for the post column chelating reagent. The peak of aluminum was separated from that of calcium, magnesium and zinc, and the chromatogram was not affected by copper(II) and iron(III). The calibration curve gave linear plots with a range of 0.0027-0.54 ppm aluminum, the regression coefficient of correlation (r2) was 1.000, and the detection limit (S/N = 3) was 0.3 ppb, indicating that the method could determine aluminum with high sensitivity. It was demonstrated that CNDA is a useful metallofluorescent reagent for aluminum. This method has been successfully applied to the determination of aluminum in some tea drinks.

The effect of low molecular weight chitosan on bone resorption in vitro and in vivo.

We studied the effect of low molecular weight chitosan (LMWC) on the formation of osteoclast-like multinucleated cells (OCLs) in the co-culture of mouse osteoblastic cells and bone marrow cells in the presence of 1alpha,25-dihydroxyvitamin D3 [1alpha,25(OH)2D3]. LMWC at 440 microg/ml inhibited the formation of tartrate-resistant acid phosphatase (TRAP)-positive OCLs induced by 1alpha,25(OH)2D3. We prepared OCLs in the co-culture of osteoblastic cells and bone marrow cells. The effect of LMWC on pit formation by OCLs was examined using dentin slices, and LMWC inhibited pit formation at 440 microg/ml. Oral administration of the LMWC to ovariectomized rats prevented a decrease in bone mineral density (BMD) of the lumbar vertebra without affecting the body and uterus weights. These results suggested that LMWC prevented a decrease in BMD in vivo by inhibiting osteoclastic bone resorption.

Antiosteoporotic activity of the stems of Sambucus sieboldiana.

We previously found that a methanolic extract of the stems of Sambucus sieboldiana inhibited bone resorption in organ culture. In this study, we further fractionated the methanol extract guided by the activity towards bone resorption stimulated by parathyroid hormone (PTH) in vitro. The ethyl acetate fraction (EtOAc Fr.) of the methanolic extract inhibited PTH-stimulated bone resorption of neonatal mouse bones, and the inhibitory activity was more potent than those of other fractions. Oral administration of the EtOAc Fr. (50 and 100 mg/kg/d) to ovariectomized (OVX) rat prevented the decrease in bone mineral density (BMD) of the lumbar (L2-4) vertebra, indicating that the EtOAc Fr. is effective in vivo. Furthermore, the EtOAc Fr. (50, 100 and 150 mg/kg/d) decreased the serum calcium level elevated in low calcium dietary rats. The phenolic constituents of the EtOAc fraction were examined for their inhibitory effect on bone resorption stimulated by PTH in neonatal mouse bone. Among them, vanillic acid, vanillin and coniferyl alcohol showed significant inhibitory effects on bone resorption. Of the compounds examined, vanillic acid was found to have a significant inhibitory effect on the decrease of BMD in OVX mice. Therefore, the EtOAc Fr. of S. sieboldiana showed a suppressive effect on bone resorption in vitro and in vivo. In addition, the inhibitory effects of the EtOAc Fr. on bone resorption may be at least partly due to the inhibitory action of vanillic acid.

Lecithinized superoxide dismutase attenuates phorbol myristate acetate-induced injury in isolated dog lung.

Lecithinized superoxide dismutase, a lecithin derivative bound to recombinant human CuZn superoxide dismutase, has a higher affinity for cells such as polymorphonuclear leukocytes and endothelial cells than recombinant human CuZn superoxide dismutase has. We determined the protective effects of lecithinized superoxide dismutase on the increased microvascular permeability induced by phorbol myristate acetate (PMA) in isolated dog lungs. Microvascular permeability was assessed by the capillary filtration coefficient (Kf,c) and solvent drag reflection coefficient (sigma(f)). PMA (13.3 microg) increased microvascular permeability, as evidenced by an increase in Kf,c and the small sigma(f) value. Lecithinized superoxide dismutase at both low (4800 U) and high doses (48,000 U) inhibited the PMA-induced increase in Kf,c, but only the high dose of lecithinized superoxide dismutase attenuated the decrease in sigma(f). Recombinant human CuZn superoxide dismutase did not affect the PMA-induced increase in vascular permeability at either a low (4800 U) or a high dose (48,000 U). These findings suggest that lecithinized superoxide dismutase has a protective effect against oxygen radical-induced lung injury in isolated dog lungs.

The effect of Kampo formulae on bone resorption in vitro and in vivo. I. Active constituents of Tsu-kan-gan.

Four water extracts of Kampo formulae (Yi-kkan-sen, Dai-ho-in-gan, Ni-chi-gan, Tsu-kan-gan) were screened for their inhibitory activities on bone resorption induced by parathyroid hormone (PTH) in organ culture using neonatal mouse parietal bones. Among the Kampo formulae, Tsu-kan-gan (TKG) showed the most potent inhibitory activity. We further fractionated the TKG water extract by monitoring the inhibitory activity on bone resorption stimulated by PTH in vitro. The MeOH fraction of the water extract inhibited PTH-stimulated bone resorption, and its inhibitory activity was more potent than those of other fractions. The MeOH fraction was then subjected to Sephadex LH-20 column chromatography to give fractions I, II and III, which were examined for bone resorption activity. Fraction I inhibited PTH-stimulated bone resorption, and its inhibitory activity was more potent than those of the other fractions. Upon oral administration of the three fractions (100 mg/kg/d) to ovariectomized (OVX) mice, fractions I and III prevented the decrease of bone mineral density (BMD) of the lumbar vertebra. Eleven compounds isolated from the MeOH fraction were examined for their inhibitory effect on PTH-stimulated bone resorption. Among them, berberine (1), syringin (3), limonin (4) and mangiferin (10) showed a significant inhibitory effect on bone resorption. In the formation assay of osteoclast-like cells, these compounds decreased the number of tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cells (MNCs). The inhibitory effect of TKG on bone resorption may be at least partly due to the inhibitory action of these compounds.

Effects of Cimicifugae rhizoma on serum calcium and phosphate levels in low calcium dietary rats and on bone mineral density in ovariectomized rats.

We studied the effects of ethyl acetate-(EtOAc) soluble fractions from methanol (MeOH) extracts of Cimicifugae rhizoma derived from two species - Cimicifuga heracleifolia Komarov and C. foetida L. - and four triterpenoids (1-4) isolated from them on the serum calcium (Ca) and phosphate (P) levels in low - Ca dietary rats. The EtOAc-soluble fraction from C. heracleifolia Komarov (HE) significantly drecreased Ca levels when administered. Similarly, the EtOAc-soluble fraction from C. foetida L. (FE) significantly lowered serum Ca levels at doses of 100 and 200 mg/kg/day, while the four triterpenoids (1-4) did the same at a dose of 25mg/kg/day. Interestingly only 7,8-didehydro-24-0-acetylhydroshengmanol-3-0-ß-xyloside (4) showed a significant influence on serum P levels. The effects of HE and FE on the bone mineral density (BMD) of the lumbar spine (L 2-4) in ovariectomized rats were measured by dual energy X-ray absorptiometry (DXA). Rats treated with HE and FE showed a significant increase in BMD compared to untreated ovariectomized rats. BMD was lower in the latter than in sham-operated rats.

Effects on cultured neonatal mouse calvaria of the flavonoids isolated from Boerhaavia repens.

A MeOH extract from the whole plant of Boerhaavia repens was found to inhibit bone resorption induced by parathyroid hormone (PTH) in tissue culture. Systematic separation of the MeOH extract afforded one new and two known flavonoid glycosides, namely, eupalitin 3-O-beta-D-galactopyranosyl-(1-->2)-beta-D-glucopyranoside (1), eupalitin 3-O-beta-D-galactopyranoside (2), and 6-methoxykaempferol 3-O-beta-D-(1-->6)-robinoside (3). The structure of the new compound 1 was determined using spectroscopic techniques. The inhibitory activity of these substances toward bone resorption induced by PTH was evaluated, and compounds 1 and 2 were found to exhibit significant activity.

Effects of muscle relaxation therapy using specially designed plates in patients with pulmonary emphysema.

It has been suggested that respiratory muscle dysfunction plays a major role in the development of acute ventilatory failure in patients with chronic obstructive pulmonary disease (COPD). In this study, we devised a respiratory muscle relaxation maneuver using wedge-shaped wooden plates, with which pressure was exerted on the intercostal and accessory respiratory muscles by hand, or by tapping with a wooden hammer, for 15-20 minutes twice a day. The muscle relaxation maneuver was performed in 5 moderate to severe pulmonary emphysema patients for 4 weeks and in 7 emphysema patients for 6 weeks, and the effects on pulmonary function were examined. After the therapy, inspiratory capacity (IC) and vital capacity (VC) in both the 4 weeks-and 6 weeks-treated groups, and the forced expiratory volume in 1 second (FEV 1.0) in the 6 weeks-treated group were significantly increased, and CO2 retention had also improved. Daily peak expiratory flow (PEF) showed significant increases from 2 weeks after the initiation of the therapy. These results suggest that the respiratory muscle relaxation maneuver is effective for improving the pulmonary function of pulmonary emphysema patients.

Hemodynamic mechanisms of antianginal action of calcium channel blocker nisoldipine in dynamic exercise-induced angina.

To investigate the mechanism of antianginal action of the calcium channel blocker nisoldipine and to determine the reproducibility of the clinical and hemodynamic events induced by supine leg exercise, 30 patients with stable effort angina pectoris were studied. They were divided into two groups; one group of 19 patients received a single 10-mg dose of nisoldipine orally, and the other group of 11 patients received a single dose of placebo orally. Chest pain was induced in all of 30 patients during the control exercise test. After nisoldipine administration, chest pain was not induced in 13 of 19 patients and was of lessened severity in five patients with the same work load as those performing control exercise. ST segment at peak exercise showed less severe depression after nisoldipine. Systemic vascular resistance was reduced by 38% (p less than 0.001) at rest and 22% (p less than 0.001) at peak exercise, and coronary vascular resistance was reduced by 31% (p less than 0.01) at rest and 18% (p less than 0.01) at peak exercise. Pulmonary artery wedge pressure fell from 6 +/- 1 to 3 +/- 1 mm Hg (p less than 0.001) at rest and from 28 +/- 3 to 11 +/- 2 mm Hg (p less than 0.001) at peak exercise. Coronary sinus flow at rest and myocardial oxygen uptake both at rest and during exercise was not modified by nisoldipine. However, coronary sinus flow at peak exercise increased significantly from 219 +/- 24 to 249 +/- 31 ml/min (p less than 0.01) after nisoldipine, and myocardial oxygen uptake was not significantly changed despite decreased coronary vascular resistance. The clinical and hemodynamic events induced by the exercise during invasive studies (except pulmonary artery wedge pressure at rest) were reproducible after placebo administration. Our data demonstrate that increased coronary blood flow could be the major mechanism of the antianginal action of nisoldipine in supine leg exercise-induced angina.

A suitable culture medium for ossification of embryonic chick femur in organ culture.

To establish a culture medium which allows ossification in organ culture, 9-day-old embryonic chick femurs were cultured in variously supplemented BGJb-HW2 media. Changes of Ca and Pi concentrations in the BGJb-HW2 medium or the 10% addition of chick embryo extract (CEE) did not induce ossification. Furthermore, combinations of the 10% CEE with a high Ca x Pi product or with 5 mM beta-glycerophosphate (beta-GP) or with 10% horse serum plus a high Ca x Pi product often caused pathological abnormalities in the periosteum. On the other hand, BGJb-HW2 medium supplemented with 5 mM beta-GP induced development of ossification. The Ca content of femurs and the diaphysial hydroxyproline content were markedly increased. Histological observation showed a formation of a thick and active periosteum, numerous osteoblastic cells, a sufficient amount of osteoid tissue and well developed calcified trabeculae without any pathological changes. Thus, the organ culture system using this medium was considered to be an appropriate one for studies on osteogenesis in vitro.

[A trial of suppressing secondary hyperparathyroidism by oral high dose therapy of 1, 25-dihydroxyvitamin D3].

We reported a successful treatment of secondary hyperparathyroidism by intermittent oral administration of high dose of 1, 25 dihydroxycholecalciferol [1.25-(OH)2D3] in three patients on maintenance hemodialysis. Dialysis durations were 4 months in case 1, 6.5 years in case 2 and 12.5 years in case 3. The levels of c-PTH ranged from 4.7 ng/ml to 94.2 ng/ml. 1, 25-(OH)2D3 in dosages up to 8.0 micrograms was given once a week just after hemodialysis. Before the administration and after 48 hours, serum Ca, serum Pi, serum Mg, c-PTH and highly sensitive PTH were assayed. There was a significant correlation between max. plasma concentration of 1, 25-(OH)2D and logarithm of the dose in all patients. The max. plasma level of 1, 25-(OH)2D reached 25-(OH)2D reached to 200 pg/ml at 4 hours after the oral administration of 8.0 micrograms. Their thresholds of 1, 25-(OH)2D level which could decrease the PTH levels were elevated proportionally to their dialysis durations. Case 1 required 4.0 micrograms to suppress secondary hyperparathyroidism, whereas, case 2 and 3 did 8.0 micrograms of 1, 25-(OH)2D3. Severe hypercalcemia was not observed during a high dose treatment. In conclusion, we have succeeded in treating refractory secondary hyperparathyroidism by intermittent oral administration of high dose 1, 25-(OH)3D3. This therapy is recommended to start in the earlier stage of a long-term dialysis in order to prevent severe secondary hyperparathyroidism and bone disease.

Graded nephron mass reduction and renal synthesis of 1,25-dihydroxyvitamin D3 in the rat.

The effect of graded nephron mass reduction by partial nephrectomy and the influence of parathyroid hormone and dietary phosphorus (P) on the production of 1,25-dihydroxy-vitamin D [1,25(OH)2D] were studied in vitamin D deficient rats. At 48 hours (acute experiments) or 2 weeks (chronic experiment) after partial nephrectomy, the rates of [3H]1,25(OH)2D production from [3H]25 hydroxyvitamin D (25-OHD) were measured in vivo. The production of 1,25(OH)2D decreased in proportion to the remaining nephron mass, and it was not greater in chronic experiments than in acute experiments at any level of nephron mass reduction. By contrast, plasma creatinine was elevated in 5 of 6 nephrectomized rats in acute, but not in chronic, experiments, suggesting the compensatory mechanism for renal excretory function but not for 1,25(OH)2D production. Further, at any level of nephron mass reduction, the production of this active metabolite was not greater in rats fed low P diet than those fed normal or high P diets. Thyroparathyroidectomy at 12 hours prior to a dose of [3H]-25)OHD suppressed 1,25(OH)2D production at any level of nephron mass reduction in rats fed normal or high P diet. These data suggest that in both experimental acute and chronic renal failure 1,25(OH)2D production is proportional to residual nephron mass and that parathyroid hormone may enhance the metabolism of 25OHD in renal failure and also may be critical for 1,25(OH)2D in normal or high P diet.