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PCR coupled with electrospray ionization mass spectrometry (PCR/ESI-MS) was compared with culture for pathogen detection in peritoneal dialysis (PD)-related peritonitis. Of 21 samples of PD effluent, PCR/ESI-MS identified microorganisms in 18 (86%) samples, including Mycobacterium tuberculosis in 1 culture-negative sample. Of 15 double-positive samples, PCR/ESI-MS and culture reached levels of agreement of 100% (15/15) and 87.5% (7/8) at the genus and species levels, respectively. PCR/ESI-MS can be used for rapid pathogen detection in PD-related peritonitis.

BACKGROUND AND STUDY AIM: Although narrow-band imaging (NBI) in endoscopy can improve detection of early-stage esophageal malignancies in patients with head and neck cancers, false-positive results may be obtained in areas with nonspecific inflammatory changes. This study evaluated the feasibility of primary screening with NBI and magnification for the presence of esophageal malignancies in these cancer patients. PATIENTS AND METHODS: Sixty-nine patients with documented head and neck cancers were enrolled from April 2008 to January 2009. All patients underwent a meticulous endoscopic examination of the esophagus using a conventional white-light system followed by re-examination using the NBI system and final confirmation with NBI plus magnification. RESULTS: Twenty-one patients (30.4 %) were confirmed to have esophageal neoplasia. Among these 21, 16 (76.2 %) had synchronous lesions, 9 (42.9 %) were asymptomatic, and 10 (47.6 %) had early-stage neoplasia. The incidence of multiple esophageal neoplasia was 57.1 %. NBI was more effective than conventional endoscopy in detecting neoplastic lesions (35 lesions in 21 patients vs. 22 lesions in 18 patients) and was particularly effective in patients with dysplasia (13 lesions in 9 patients vs. 3 lesions in 3 patients). The sensitivity and accuracy of detection were 62.9 % and 64.4 % for conventional endoscopy, 100 % and 86.7 % for NBI alone, and 100 % and 95.6 % for NBI with high magnification, respectively. CONCLUSIONS: Compared with current approaches, NBI followed by high magnification significantly increases the accuracy of detection of esophageal neoplasia in patients with head and neck cancers. The result warrants conducting prospective randomized controlled study to confirm its efficacy.

Aminophylline is known to have respiratory stimulant properties, and it has been suggested that it may also be effective in sleep apnoea. However, its role in this disorder remains uncertain. Theoretically, increasing upper airway motoneural activity in order to maintain airway patency might alleviate obstructive sleep apnoea. On the other hand, increasing the respiratory drive may also prove beneficial in treating central sleep apnoea. In these studies, we attempted to determine the effect of aminophylline on neural activities of the upper airway and diaphragm. We administered intravenously either a low dose (4 mg.kg-1) or a high dose (16 mg.kg-1) of aminophylline to decerebrated, vagotomized and paralysed cats, and continuously recorded the phrenic hypoglossal and recurrent laryngeal nerve activities for 3 h. Results showed that a high dose of aminophylline induced a marked increase in phrenic nerve activity, but not hypoglossal or recurrent laryngeal nerve activity. In a group treated with a low dosage of aminophylline, a significant increase of activity was found in all three nerves. Furthermore, phrenic nerve activity increased more with a high dose than with a low dose. We confirmed that aminophylline has dose-dependent and selective effects on respiratory neural activity. A low dose acts on the upper airway and diaphragm, but a high dose induces a marked increase in central respiratory drive. According to our results, low dose aminophylline might be beneficial in obstructive sleep apnoea, whereas, a high or low dose might improve some cases of central sleep apnoea.

This study applied frequency analysis to compare changes in the power spectrum density functions of surface electromyograms obtained from the paired masseter and anterior temporal muscles during therapy with three types of functional appliances, namely the Bionator, modified Fränkel type I, and Fränkel type III. Eighteen children were divided into three groups receiving either Bionator, Fränkel type I, or Fränkel type III therapy; a fourth group consisting of six children who received no therapy served as control. Before and after 3, 6, and 12 months of therapy, each child performed maximum voluntary isometric clenches in the position of maximum intercuspation. The mean frequency of the power spectrum was the variable studied. Children treated with the Bionator and Fränkel type I appliances showed greater changes in mean frequency than those treated with the Fränkel type III appliance. Although the muscles of untreated children also showed shifts of mean frequency to lower frequency values as a function of time, there was a greater downward shift of mean frequency in those treated with functional appliances. The downward shifts might have been associated with changes in muscle fiber lengths and/or recruitment patterns as a result of both treatment and normal growth.

DNA tests in normal subjects and patients with ataxia and Parkinson's disease (PD) were carried out to assess the frequency of spinocerebellar ataxia (SCA) and to document the distribution of SCA mutations underlying ethnic Chinese in Taiwan. MJD/SCA3 (46%) was the most common autosomal dominant SCA in the Taiwanese cohort, followed by SCA6 (18%) and SCA1 (3%). No expansions of SCA types 2, 10, 12, or dentatorubropallidoluysian atrophy (DRPLA) were detected. The clinical phenotypes of these affected SCA patients were very heterogeneous. All of them showed clinical symptoms of cerebellar ataxia, with or without other associated features. The frequencies of large normal alleles are closely associated with the prevalence of SCA1, SCA2, MJD/SCA3, SCA6, and DRPLA among Taiwanese, Japanese, and Caucasians. Interestingly, abnormal expansions of SCA8 and SCA17 genes were detected in patients with PD. The clinical presentation for these patients is typical of idiopathic PD with the following characteristics: late onset of disease, resting tremor in the limbs, rigidity, bradykinesia, and a good response to levodopa. This study appears to be the first report describing the PD phenotype in association with an expanded allele in the TATA-binding protein gene and suggests that SCA8 may also be a cause of typical PD.

The effects of hypercapnia and hypocapnia on the activities of the cardiac and pulmonary vagal single fibers were examined in the decerebrated, unanesthetized, paralyzed, and vagotomized cats. The animals breathed 100% O2. Fractional end tidal CO2 concentration was raised to 9% by adding CO2 into the O2 inlet. Average discharge rate of efferent cardiac vagal units (n=10) increased from 1.0+/-0.3 to 2.2+/-0.3 Hz. Hypocapnia apnea was produced by hyperventilation. Activities of cardiac vagal units tested (n = 4) showed dramatic decrease (0.1+/-0.0 Hz). Mean arterial blood pressure did not change significantly under these conditions. In contrast, only instantaneous firing rate during inspiration was significantly increased for efferent pulmonary vagal units (n = 11) during hypercapnia. The activities of the 3 pulmonary vagal units tested with hypocapnia decreased significantly. We concluded that cardiac and pulmonary vagal neurons were excited by chemoreceptor input.

The effects of electrical and chemical activation of the rostral ventrolateral medulla (rVLM) on respiratory-related facial nerve activity were investigated in decerebrated, paralyzed, vagotomized and ventilated cats. The animal was maintained at normocapnia and hypercapnia in hyperoxia. Phrenic and facial nerve activities were simultaneously recorded. Excitation of the rVLM either by electrical current (12.5 to 50 microA, 80 Hz and 0.5 ms pulse duration) or glutamate microinjection (50 mM, 20 to 200 nl) inhibited both phrenic and facial nerve discharges. Although inhibition of the rVLM upon both nerves was attenuated by hypercapnia, this inhibition remained significant during hypercapnia. These results suggest that the rVLM may be involved in the modulation of upper airway patency by controlling respiratory-related facial nerve activity.

A luteolytic dose (500 micrograms) of cloprostenol was given four days before expected estrus to five mature cyclic cows of native Taiwan Yellow cattle. Blood samples were collected at hourly intervals for 60 hours and then twice daily (0800 h and 1600 h) until onset of the following estrus or Day 29 after prostaglandin (PG) injection. Plasma progesterone levels were quite low in the follicular phase and elevated over an 11-13 day period during the luteal phase for every animal. Two cows showed peak luteinizing hormone (LH) levels of 19.97 and 23.77 ng/ml of plasma at 120 and 127 h after PG injection. One cow did not show peak LH level during the 60-h sampling period, but had its highest concentration of 18.02 ng/ml at 0800 h on Day 8. Two cows showed no detectable peak LH during the 60-h sampling period or on subsequent days. But these two cows had increased concentrations of progesterone beginning on Day 6 and Day 12. All animals came back into estrus 23-28 days after PG treatment.

The purpose of the present study was to examine respiratory-modulated facial nerve activity (FNA) in response to activation of the ventrolateral subarea of the nucleus of the tractus solitarius (vlNTS). The cat was anesthetized with sodium pentobarbital and then vagotomized bilaterally, paralyzed and ventilated artificially. End-tidal fractional concentration of CO2 was maintained at hyperoxic normocapnia. Partial occipital craniotomy was performed to expose the obex. Activities of the phrenic and the facial nerves were simultaneously recorded. The vlNTS was excited by electrical current (80 Hz frequency, 0.5 ms pulse duration and a variety of current from 12.5 to 50 microA) and glutamate (30-100 nl, 0.5 M). Three responsive patterns for both nerves were observed in response to vlNTS activation. First, inspiratory facial nerve activity (iFNA) and phrenic nerve activity (PNA) were decreased (p0.01), while expiratory facial nerve activity (eFNA) was not changed. Second, iFNA and PNA were diminished (p0.01) but eFNA was enhanced. Third, iFNA was decreased whereas PNA was enhanced. These results suggest that there might be a neural pathway projecting from the vlNTS to the facial nuclei to modulate respiratory-modulated facial nerve activities.

Cardiorespiratory responses, including changes of systemic arterial pressure (SAP), renal or splanchnic sympathetic nerve activity (SNA) and phrenic nerve activity (PNA), were elicited by microinjection of monosodium glutamate solution (0.5 M, 100 nl) into the dorsal (DM) and rostral ventrolateral medulla (RVLM) in 15 vagotomized cats anesthetized by urethane-chloralose and paralyzed by gallamine triethiodide. Artificial ventilation was adjusted to keep the end-tidal CO2 concentration at 4.0-0.5%. Sixty two pressor and 17 non-pressor sites were stimulated. Most of the stimulations inhibited the PNA. The responses of SNA was variable, showing increases, decreases or no change. Inhibition of SNA during SAP increase was not secondary to baroreceptor activation as the inhibition persisted in carotid sinus/aortic denervated animals. Although various combinations of changes of SNA and PNA were observed, their temporal courses were similar in many instances. Attenuation of SNA and PNA was synchronized, suggesting that these changes are coupled in the stimulating sites. The findings suggest that some neurons in DM and RVLM act as a functional unit to modulate cardiorespiratory functions whereas others simply coexist in the same area independent from each other.

There is only limited information of the neurotransmitters in central respiratory control. L-glutamic acid has been proposed as the primary neurotransmitter in the nucleus of the tractus solitarius (NTS) in cats. To test whether there is a respiratory effect of glutamic acid in the respiratory center or not, we microinjected L-glutamic acid (1 M, 0.1 microliter) via 1 microliter Hamilton microsyringe into the ventrolateral nucleus of NTS, namely dorsal respiratory group (DRG) over two-second intervals with continuous monitoring of phrenic nerve activity (PNA), frequency (f), end tidal CO2, blood pressure and heart rate. Glutamate induced various respiratory changes including: increase in PNA and f decrease in PNA and f [corrected] increase in PNA but decrease in f and decrease in PNA but increase in f. In addition to regular changes of PNA or f elicited by glutamate microinjection were found. Other patterns of irregular rhythmic changes such as absence of PNA, continuous phrenic nerve discharge and irregular phrenic nerve discharge with reflex apnea, apneusis and irregular respiration respectively were also observed. Glutamic acid appears to significantly modulate respiratory drive in DRG. We suggested that L-glutamic acid may be a neurotransmitter in the respiratory center and be involved in central respiratory control.

An attempt was made to explore the possibility of using the masticatory muscle reflexes as pain indices in human subjects. It was found that the digastric reflex, so readily evoked by electrodental stimulation in experimental animals, could not be consistently elicited in man. The reflex silent period of the masseteric muscles, on the other hand, may be used as a pain index for evaluating dental analgesia, provided that analgesic interference is anticipated at points along the reflex arc.

The power spectrum of electromyograms (EMG) has been demonstrated to vary with muscles having different muscle fiber type compositions. This study investigated the variations in EMG power spectrum patterns of the masticatory muscles with age and gender by comparison of the mean power frequency (MPF) of the anterior temporal and masseter muscles in children and adults. Surface EMG signals were sampled bilaterally from the muscles when the subjects were performing maximum voluntary isometric clenches at maximal intercuspal position. The results indicated that MPF values were age-dependent (p

A search in ancient Chinese medicinal literature and modern phytochemical reference indicates that the therapeutic value of Leonurus artemisia (I-mu ts'ao, the Chinese motherwort) might reside in a uterotonic principle present in leaves. Leonurine (4-guanidino-n-butyl syringate) was isolated from fresh and dry leaves of Leonurus artemisia. The uterotonic effect of leonurine was demonstrated in rat uterus in vitro. Results from this study suggest that functional phytochemistry based on ethnobotanical experience could lead to development of new and effective drugs from Chinese medicine.

A method for the assessment of induced regional dental analgesia in experimental animals is described. It is based on the validity of the electrodentally elicited digastric electromyogram as a pain index. This method has been applied to study the effectiveness of one local anesthetic and of “electroacupuncture” to suppress pain regionally.

In order to evaluate the effect of changing respiratory mechanics on the relation between respiratory mechanical output and phrenic activity, we simultaneously measured ventilatory output from the trace of pneumotachograph and changes in phrenic nerve activity before and after pneumothorax in alpha-chloralose anesthetized dogs. After pneumothorax, the dynamic lung compliance, inspiratory duration and tidal volume were decreased significantly, whereas the integrated peak amplitude and the rate of rise of phrenic neural output were increased substantially. The difference between respiratory mechanical output and phrenic activity was also significant (p less than 0.05). As shown from the results, the increase of phrenic response to pneumothorax may be mediated through intrapulmonary receptors along the vagal afferent rather than through the changes in chemical drive.

The effects of superfusion of morphine, met-enkephalin and D-ala2-met5-enkephalinamide on the spontaneous neural discharge rates of units in the spinal trigeminal nucleus and cuneate nucleus of decerebrate cats were studied. The drugs were superfused onto the dorsum of the exposed surface of the caudal medulla overlying these nuclei. Some of these neurons were identified by their response to innocuous mechanical stimuli delivered to the skin. In the caudal spinal trigeminal nucleus, morphine caused a dose-dependent suppression of the spontaneous discharge rate in the majority of the neurons studied. Endogenous opiate peptide, met-enkephalin or its synthetic analogue, D-ala2-met5-enkephalinamide caused an initial reduction, followed by a rebound of the discharge rate to the control value. These depressant effects of morphine and enkephalins were antagonized by concomitant superfusion of the opiate antagonist naloxone. In the main cuneate nucleus, however, similar doses of morphine, met-enkephalin and D-ala2-met5-enkephalinamide have little if any significant effect on the spontaneous activity of the neurons studied. These results provide electrophysiological evidence for the presence of opiate receptors in the caudal spinal trigeminal nucleus and the relative lack of such receptors in the main cuneate nucleus.

The purpose of the present study was to examine the afferent mechanisms for phasic hypoglossal and phrenic responses to airflow changes in the upper airway (UAW). An isolated UAW was produced in decerebrate, unanesthetized, vagotomized, paralyzed and ventilated cats. Activities of both the hypoglossal and phrenic nerves were monitored at hyperoxic (FETCO2 greater than 0.80) normocapnia (FETCO2 = 0.04-0.05). As inspiratory airflow passing through the UAW, hypoglossal activity enhanced significantly while phrenic discharge reduced (p less than 0.01). After bilateral denervation of the superior laryngeal nerve (SLN), enhancements of hypoglossal activity in response to the same level of airflow were much lower whereas reduce in phrenic discharge was eliminated. Combined with sectioning of the glossopharyngeal nerve (GPN), augmentation of hypoglossal response to airflow was even higher. This increase in hypoglossal activity with airflow changes was not discerned when the trigeminal ganglion (TGG) was further destroyed. These results suggest that airflow changes in the UAW, which was sensed by the receptors in the SLN, GPN, and TGG, produce an increase in hypoglossal discharge and a decrease in phrenic burst. Increase in hypoglossal activity in response to airflow change in the UAW may relate to keeping a patent UAW.

The duration of the masseteric EMG silent period as induced by tapping on the chin was measured at different levels of sustained bite force. Under both open bite and normal occlusion, the duration of the silent period was inversely related to the magnitude of the bite force. For bite force of the same magnitude, the value of the silent period remained relatively constant for the same subject in different trials (SEM ≅ 1 per cent), whereas the absolute values of the silent periods ranged far and wide for different individuals even under similar experimental conditions.

Only limited information relating neurotransmitters to central regulation of the respiratory system exists. L-glutamic acid has been proposed as the primary neurotransmitter in the nucleus of the tractus solitarius (NTS) of cats. To test whether or not glutamic acid has an effect on the respiratory center, we microinjected L-glutamic acid (1 M, 0.1 microliter) via a 1 microliter Hamilton microsyringe into the ventrolateral area of the NTS dorsal respiratory groups (DRG) of unanesthetized, decerebrated cats at two-second intervals with continuous monitoring of tidal volume (VT), respiratory rate (f), end tidal CO2, blood pressure and heart rate. The results showed that glutamate induced the following respiratory changes: VT and f increased; VT and f decreased; and VT decreased but f increased. In addition to VT or f changes elicited by glutamate microinjection, changes in other rhythmic patterns such as apnea, apneusis and irregular respiration were observed. Glutamic acid appears to play a significant role in the modulation of the respiratory drive in the DRG. We, therefore, suggest that the excitatory amino acid L-glutamic acid may be involved in central respiratory control.

We checked serum beta-endorphin levels in 17 chronic uremic patients under regular hemodialysis and compared them with the levels in 17 age-matched control subjects. Higher levels of serum beta-endorphin were found in uremic patients (22.54 +/- 6.20 pg/0.1 ml vs 9.42 +/- 5.19 pg/0.1 ml, p less than 0.001). There were no sex differences in both uremic patients (M: F = 21.04 +/- 7.53 pg/0.1 ml vs 23.59 +/- 5.25 pg/0.1 ml, p greater than 0.05) and normal control subjects (9.16 +/- 5.15 pg/0.1 ml vs 9.76 +/- 5.55 pg/0.1 ml, p greater than 0.05). No significant difference in the serum levels was noted between the patients with a hemodialysis history longer than two years (19.96 +/- 5.79 pg/0.1 ml vs 25.45 +/- 5.60 pg/0.1 ml, p greater than 0.05) and those with less than a two year's history (19.96 +/- 5.79 pg/0.1 ml vs 25.45 +/- 5.60 pg/0.1 ml, p greater than 0.05). Moreover, serum beta-endorphin levels were not altered after dialysis (22.54 +/- 6.20 pg/0.1 ml to 20.66 +/- 4.57 pg/0.1 ml, p greater than 0.05) by either acetate or bicarbonate dialysate (acetate vs bicarbonate = 20.83 +/- 5.03 pg/0.1 ml vs 20.13 +/- 3.14 pg/0.1 ml, p greater than 0.05). The role of beta-endorphin in the pathogenesis of uremic syndrome still requires further study.

The purpose of the present study was to evaluate the response of respiratory-modulated facial nerve to electrical activation on the superior laryngeal nerve (SLN). The experiments were performed on fifteen cats which were anesthetized with pentobarbital, vagotomized, paralyzed and artificially ventilated. The animals were maintained at different levels of carbon dioxide in hyperoxia. Parameters of electrical stimulation were 20 Hz of frequency, 0.5 mSec of duration and a variety of intensity (30, 50, 100 and 150 microA). Facial activity increased significantly (P less than 0.05) in response to SLN activation. This augmentation of facial discharge was proportional to the intensity of electrical activation on the SLN. Phrenic response to SLN stimulation was either decreased or not changed. Total duration of respiratory cycle after activation of the SLN was increased. The results showed that facial activity may play a role in the regulation of nasal resistance.

The effect of lanthanum ion on the contraction of the perfused guinea-pig heart has been investigated. Lanthanum caused inhibition of the contractile force. The dose-response curves suggest that there is more than one site with which lanthanum may interact. The high affinity interaction is antagonised by high external calcium. The possibility that a low concentration of lanthanum may block calcium entry into the myocardium is discussed.

Electrical and chemical stimulation methods were used to determine the topographic organization of the medullary raphe nuclei (MRN) in controlling the systemic arterial blood pressure (BP) and phrenic nerve activities (PNA). Decerebrated, unanesthetized and bilateral vagotomized cats were used. Effective points in the MRN were systematically explored with constant current stimulation. We found stimulation of the rostral MRN produced a decrease in PNA amplitude and increase in BP and PNA frequency. Stimulation of the caudal MRN produced increases in BP and the amplitude and frequency of PNA. Microinjection of glutamate solution into the caudal or the rostral MRN points produced qualitatively similar results. Thus, we concluded that the caudal MRN neurons had excitatory connections whereas the rostral MRN neurons had excitatory and inhibitory connections to the cardiovascular preganglionic neurons and the phrenic nerve motoneurons.