Effect of Ginkgo biloba on Expression of c-Fos Protein in the Vestibular Nuclear Complex following Unilateral Labyrinthectomy in Rats

BACKGROUND AND OBJECTIVES: The neuroprotective effect of Ginkgo biloba has been demonstrated in several in vivo and in vitro models. The effect of Ginkgo biloba on vestibular compensation following unilateral labyrinthectomy (UL) was investigated. Material and Methods: Spontaneous nystagmus and c-Fos protein expression were measured following UL in Sprague-Dawley rats with pretreatment of Ginkgo biloba (50 mg/kg, i.p.). RESULTS: After pretreatment with Ginkgo biloba (50 mg/kg, i.p.) expression of c-Fos protein in the vestibular nuclear complex and frequency of spontaneous nystagmus were measured till 24 hours after UL. UL produced spontaneous nystagmus with frequency of 124+/-.2 beats/min at post-op 2 hrs and 70+/-.1 beats/min at post-op 24 hrs. Pretreatment with Ginkgo biloba significantly decreased the frequency of spontaneous nystagmus till post-op 24 hrs compared to control group (p<0.05). UL produced marked expression of c-Fos protein in bilateral medial vestibular nucleus, inferior vestibular nucleus, and superior vestibular nucleus, and the number of expression was significantly higher in contralateral vestibular nuclei to the lesion than ipsilateral vestibular nuclei at post-op 2 hrs (p<0.01). The number of c-Fos protein expression was decreased with time and significantly higher in ipsilateral vestibular nuclei than contralateral ones at post-op 24 hrs (p<0.01). Pretreatment with Ginkgo biloba significantly decreased the number of c-Fos protein expression following UL (p<0.01) and abolished the asymmetry of c-Fos protein expression in bilateral vestibular nuclei at post-op 24 hrs. CONCLUSION: These results suggest that Ginkgo biloba may facilitate vestibular compensation following UL through modulation of neurotransmitters and neuroprotective effects.

Neuronal Activity of the Vestibular Nuclei Following Acute Hypotension in Rats

The role of peripheral vestibular receptors in acute hypotension was investigated in anesthetized rats. Acute hypotension was induced by either intravenous infusion of sodium nitroprusside (SNP) or by experimental hemorrhage, and electrical activity and expression of cFos-like immunoreactive (cFL) protein were measured in the medial vestibular nuclei (MVN). Blood pressure decreased proportionately to the does of intravenous SNP and to the volume of the hemorrhage. Blood pressure decreased 10, 30, 50% for the 5, 10, 15ng/kg SNP injection, respectively, and also decreased 30 and 50% after 1- and 2-ml blood loss, respectively, due to hemorrhage. In animals with intact labyrinths, acute hypotension induced by either intravenous infusion of SNP or hemorrhage produced different electrical activities with three different patterns in type I and II neurons of MVN. The responses of type I neurons showed excitatory in 2/3 of recorded neurons and inhibitory or no change in 1/3 of neurons, while the responses of type II neurons showed inhibitory in 2/3 of recorded neurons and excitatory or no change in 1/3 of neurons. In unilateral labyrinthectomized animals, 2/3 of type I neurons ipsilateral to the lesion showed an inhibitory response, and 2/3 of contralateral type I neurons showed an excitatory response after the induction of acute hypotension. The response patterns of type II neurons were opposite from those of the type I neurons. After 30% decrease in blood pressure, cFL protein expressed in the bilateral vestibular nuclei of control animals with intact labyrinths. Expression of cFL protein increased significantly proportionately to the reduction of blood pressure. The unilateral labyrinthectomized animals with acute hypotension produced expression of cFL neurons in contralateral vestibular nuclei to the lesion side, but not in ipsilateral vestibular nuclei. However, cFL protein was not expressed in bilateral vestibular nuclei after acute hypotension in bilateral labyrinthectomized animals. These results suggest that the peripheral vestibular receptors might play a significant role in controlling blood pressure following acute hypotension via activation of type I neurons and inhibition of type II neurons in the vestibular nuclei.

Electrical stimulation can facilitate vestibular compensation following unilateral labyrinthectomy in rats

To investigate the effects of electrical stimulation on vestibular compensation, which is the recovery of vestibular symptoms following unilateral labyrinthectomy (UL), intermittent electrical stimulation was applied to the injured vestibular portion in Sprague-Dawley rats. Vestibuloocular and vestibulospinal reflexes, electrical activity and expression of c-Fos protein in medial vestibular nuclei (MVN) were measured with time following UL. Spontaneous nystagmus occurred with frequency of 2.9+/-0.2 beats/sec at 2 hours after UL and disappeared after 72 hours. Electrical stimulation decreased the frequency of nystagmus significantly till 24 hours after UL. Roll head deviation was 107+/-9.7degree at 2 hours after UL and the deviation was maintained till 72 hours, but electrical stimulation decreased the deviation significantly 6 hours after UL. Resting activity of type I neurons in ipsilateral MVN to the injured vestibular side decreased significantly compared with control at 6 and 24 hours after UL, but the activity of type I neurons was recovered to control level by electrical stimulation at 24 hours after UL. Gain of type I neurons induced by sinusoidal rotation of 0.1 Hz decreased significantly till 24 hours after UL, but electrical stimulation restored the activity at 24 hours. The gain of type II neurons decreased significantly at 6 hours after UL, but electrical stimulation restored the activity. Expression of c-Fos protein was asymmetric between bilateral MVN till 24 hours after UL, but the asymmetry disappeared by electrical stimulation 6 hours after UL. These results suggest that electrical stimulation to the injured vestibular portion facilitates vestibular compensation following UL by restoration of symmetry of neuronal activity between bilateral vestibular nuclei resulting from increased activity in ipsilateral vestibular nuclei to the injured side.

Feasibility Study of Application of UHDDS Items for Hospital Discharge Abstract and Analysis in Tertiary Care Hospitals / 대한의료정보학회지

The purpose of this study is to identify standardized items from Hospital Discharge Abstract and Analysis data by using UHDDS(Uniform Hospital Discharge Data Sets in USA) and to ascertain the computerization in tertiary hospitals. The data were collected by questionnaire survey, responded 38 hospitals(86.4%) out of 44 tertiary hospitals, and the conclusions are as follows. 1. As for the general characteristics of patient; hospital registration number, patient name, sex and social identification number were reported to 0.92%. 2. As for admission and discharge aspects; admission date was showed 0.92, type of admission and insurance were 0.87%, discharge date 0.92%, the code of primary condition, other diagnoses and primary procedure were 0.89%, disposition of discharge was 0.61%. 3. As for the other characteristics; attending physician license number and name of operating physician were showed 0.87%, birth weight of newborn 0.74%, nationality 0.44%. 4. As for the order communicating system, computerization for the medical record management was showed 57.9%, administration of outpatient 53.6%, administration of inpatient 44.7%, administration of emergency care 28.9%. Judging from the study, the development of Korean Uniform Hospital Discharge Data Sets using Discharge Abstract and Analysis System is applicable to the national wide collection of statistics on the diseases for the discharged patients.

A Survey on the Status of Health Statistics Generation by the Medical Record Offices of Hospitals and its Automation Rate / 대한의료정보학회지

We surveyed the generation rate of health statistics by medical records offices of the 78 hospitals and its automation rate using computerized hospital information system. Structured questionnaire was given to one medical record officer of each hospital. Items in the questionnaire was selected from statistics required for hospital service evaluation or OECD health statistics. More than 50% of the medical record office generated questioned health statistics, and most of them was automated. Because many of the medical record offices of the hospitals are producing essential health statistics and automated, there is a possibility that we can collect and use these datas to build up national health database if adequate standardization procedure can be implemented.