Effects of isatin, an endogenous MAO inhibitor, on dopamine (DA) and acetylcholine (ACh) concentrations in rats

Isatin (indole-2,3-dione), an endogenous inhibitor of monoamine oxidase (MAO), has several physiological properties for stress and anxiety. We previously identified isatin in the brain of stroke-prone spontaneously hypertensive rats (SHRSP) using gas-chromatography mass spectrometry. This study elucidated the effects of isatin on the ACh and DA levels of brain tissues in rats. Furthermore, we evaluated the effect of isatin on DA levels in a rat model of Parkinson's disease induced by Japanese encephalitis virus. Striatal ACh and DA levels significantly increased at 2 hours after isatin (50-200 mg/kg, i.p.) administration. Perfused through a microdialysis probe, isatin (10(-6)-10(-4) M) also produced a significant and concentration-dependent increase in the ACh and DA concentrations in the perfusate from the rat striatum. Furthermore, urinary isatin concentrations in patients with Parkinson's disease tend to increase according to the severity of disease. Isatin (100 mg/kg, i.p.) significantly increased striatal DA levels in a rat model of Parkinson's disease. These results suggest that urinary isatin may become a diagnostic marker for the clinical severity of Parkinson's disease and that endogenous isatin, a new biological modulator, may play a role in the regulation of the brain levels of ACh by increasing the level of DA under stress.     

Effects of four volatile anesthesics on postanesthetic ventilation: a comparison of halothane,enflurane, isoflurane,and sevoflurane

To investigate the effects of four volatile anesthetics (halothane, enflurane, isoflurane, and sevoflurane) on postanesthetic ventilation and levels of consciousness, we enrolled 24 patients undergoing tympanoplasty in this study. Anesthesia was maintained with 67% nitrous oxide and one of four volatile anesthetics. We measured end-tidal carbon dioxide concentration (C_ETco₂), minute volume ( ) and respiratory rate (RR), and determined the volatile anesthetic concentration in whole arterial blood (C_BAnesth) and arterial carbon dioxide tension (Paco₂) at 20 min and 2h after tracheal extubation. We also observed the level of consciousness (awake, drowsy, and asleep) before the measurement. Ventilatory variables were similar among the four groups at 20 min, although the ratio of volatile anesthetic concentration in the alveoli to the minimum alveolar concentration (MAC) (C_AAnesth/MAC ratio) calculated from C_BAnesth in the halothane group was twice those in the other groups. In the halothane group, Paco₂ was significantly higher, and and RR were significantly lower compared with the isoflurane and sevoflurane groups at 2h. Halothane tended to prolong the recovery of levels of consciousness. We conclude that isoflurane and sevoflurane provide clinical advantages over halothane on postanesthetic ventilation and recovery of levels of consciousness.     

Extrarenal Wilms' tumour

Extrarenal Wilms' tumour is rare and its imaging has received scant mention in the literature. We describe a 2-year-old boy with a firm mass in the right flank. CT, MRI and ultrasonography showed an inhomogeneous solid mass located in the retroperitoneum, which was separate from the right kidney. Angiography showed an enlarged right gonadal artery and irregularly tortuous vessels in the tumour similar to intrarenal Wilms' tumour (spider leg or creeping vine appearance). Histopathological examination confirmed an extrarenal Wilms' tumour.     

Anesthetic management of a patient with Hallermann-Streiff syndrome

Key words  airway management - difficult intubation - Hallermann-Streiff syndrome     

Analysis of spine morphological plasticity in developing hippocampal pyramidal neurons

Dendritic spines are targets of most excitatory inputs in the central nervous system (CNS) and are morphologically heterogeneous. Ultrastructural studies have traditionally classified spines into four major categories (filopodia, stubby, thin, and mushroom) based on their distinct morphologies. The recent discovery of rapid morphological plasticity of spines has raised the possibility that those categories, rather than being intrinsically different populations of spines, represent instead temporal snapshots of a single dynamic phenomenon. We examined this question with two-photon time-lapse imaging of developing hippocampal pyramidal neurons, transfected with E-GFP in cultured slices. After blind scoring to morphologically classify spines into the four traditional groups, we analyzed the fate of populations of spines over a period of 2-4 h. We found considerable morphological conversions among all categories, although systematic trends were detected. While most stubbies and spines (defined for our analysis as the combination of thin and mushroom protrusions) retained their basic morphologies, most filopodia transformed into stubbies and spines, although they could also extend out of existing spines. Our results suggest that in developing hippocampal pyramidal neurons, traditional morphological distinctions are stable over short (<4 h) periods of time, but that at the same time, considerable mixing among these groups takes place.     

Ultrasonographic evaluation of gastric emptying in normal children and children after pyloromyotomy

Gastric emptying in the fundus, body, and antrum of the stomach was evaluated by ultrasonography (US) in 41 control children aged 2 to 18 years and 30 patients aged 1 to 19 years who had undergone pyloromyotomy because of hypertrophic pyloric stenosis. The gastric emptying curve decreased in an exponential manner for both control children and patients, while there was no significant difference in gastric emptying time (GET) between control children and patients within any of the age groups. However, GET was faster for younger children in both groups. An X-ray contrast study of the stomach performed in 2 patients who showed markedly delayed GET showed delayed gastric emptying but no significant deformities of the prepylorus. Our results suggest that US is a reliable method of measuring GET in children.     

Potentiation of Paclitaxel Cytotoxicity by Inostamycin in Human Small Cell Lung Carcinoma, Ms-1 Cells

In the present study, we found that inostamycin increased the ability of paclitaxel to induce apoptosis in Ms-1 cells. A considerably higher concentration of paclitaxel was required for the induction of apoptosis in Ms-1 cells than in other cell lines tested. Treatment of Ms-1 cells with inostamycin, an inhibitor of phosphatidylinositol (PI) synthesis, reduced the dosage of paclitaxel required to induce cell death by apoptosis. This effect of inostamycin is specific to Ms-1 cells, and inostamycin did not increase the cytotoxicity of other antitumor drugs such as adriamycin, vinblastine, methotrexate, cisplatin, etoposide, or camptothecin in Ms-1 cells. Addition of inostamycin to paclitaxel-treated cells caused a significant increase in the sub G1 peak, representing apoptosis, which was accompanied by a decrease in the G2/M peak seen in paclitaxel-treated Ms-1 cells, without affecting paclitaxel-inhibited tubulin depolymerization. Moreover, paclitaxel did not enhance inostamycin-inhibited PI synthesis. The expression levels of Bcl-2, Bax, and Bcl-X_L were not changed following the co-treatment with inostamycin plus paclitaxel, whereas the activated form of caspase-3 was markedly increased. Thus, inostamycin is a chemosensitizer of paclitaxel in small cell lung carcinoma Ms-1 cells.     

Afferents of cranial sensory ganglia pathfind to their target independent of the site of entry into the hindbrain

In vertebrates, sensory neurons interconnect a variety of peripheral tissues and central targets, conveying sensory information from different types of sensory receptors to appropriate second-order neurons in the central nervous system (CNS). To explore the possibility that the different rhombomere environments where sensory neurons enter into the hindbrain affect the pathfinding capability of growth cones, we studied the development of the VIIIth ganglion afferent both in vivo and in vitro. We focused on the vestibular nerve because it is the only cranial nerve projecting to the cerebellum, allowing for ready identification from its pattern of projection. Embryonic rat brain was cut along the dorsal midline and, with the VIIIth and Vth ganglia still attached, flat mounted and visualized with antibodies specific for sensory ganglia. Axons reached the cerebellar primordium at embryonic day (E) 13, then splayed out towards the edges of the rhombic lip of rostral hindbrain. In vitro, the VIIIth ganglion showed development similar to that in vivo and innervated the cerebellum, an appropriate target, indicating that mechanisms for axon guidance and target recognition are preserved in vitro. When the VIIIth ganglion was transplanted to the position of the Vth ganglion, axons from the transplanted ganglion entered the cerebellar primordium with a trajectory characteristic of the VIIIth nerve. These results indicate that the central projection pattern of the VIIIth nerve is not affected by the environment of nerve entry into the brainstem, suggesting that axons of sensory cranial ganglion intrinsically possess the capacity to find their target correctly.