Central Hypoventilation Syndrome in Posterior Circulation Stroke Treated by Respiratory Rehabilitation: a Case Report

Central hypoventilation syndrome is a rare and fatal condition resulting from various central nervous system disorders that is characterized by a failure of automatic breathing. We report a case of central hypoventilation syndrome following posterior circulation stroke whose pulmonary function was improved by respiratory rehabilitation. A 59-year-old woman with a history of hemorrhagic stroke of the bilateral cerebellum was hospitalized due to pneumonia. A portable ventilator was applied via tracheostomy, recurrent episodes of apnea and hypercapnia impeded weaning. A respiratory rehabilitation program including chest wall range of motion exercise, air stacking exercise, neuromuscular electrical stimulation (NMES) on abdominal muscles, upper extremity ergometer, locomotor training, high-frequency chest wall oscillator, mechanical insufflation, and exsufflation was employed, as spirometry showed a severe restrictive pattern. A spontaneous breathing trial was started, and a portable ventilator was applied for 8 hours, only during nighttime, to prevent sudden apneic event. After 4 weeks of treatment, follow-up spirometry showed much improved respiratory parameters. This case suggests that respiratory rehabilitation can improve pulmonary function parameters and quality of life in central hypoventilation syndrome.

The effect of mechanical or electrical stimulation on apnea length in mice

Premature birth is a leading cause of infant mortality which is often attributed to irregular breathing and apnea of prematurity. A common treatment for apnea is caffeine to stimulate the brain's respiratory center. However, caffeine's long term effect on infant development is not fully comprehended. We hypothesized that noninvasive localized body stimulation regularizes breathing pattern. We investigated the impact of electrical or mechanical stimulation on breathing in mice. After the mice were ventilated for 28 s to induce apnea, mice were taken off the ventilator while receiving mechanical, electrical, or no stimulation in a randomized order. Both stimuli targeted the diaphragm area through a custom-built belt with vibrating motors or adhesive electrodes. After each apnea cycle, the time to take the first breath (T) was recorded. The electrical stimulation given at 4.5, 8.3, 16.7 V (pulse rate = 3 Hz, pulse width = 120 μs) showed no reduction in T. Electrical stimulation at pulse rates of 10 or 20 Hz (16.7 V, pulse width 260 μs) showed a detrimental effect increasing T by ~ 7% compared to control values (p = 0.005, p = 0.038 respectively). High and medium intensity mechanical stimulations significantly reduced T by 11.74 (p<10⁻¹³) and by 17.08% (p<10⁻⁸), respectively. Further reducing the amplitude of vibrations did not affect T. When the probe was attached to the ankles, only the high intensity vibrations resulted in a decrease in T (p<10⁻¹³). Mechanical vibrations, applied at various intensities and locations, could be used to treat irregular breathing and apnea in infants.

Sleep Disorder and Alcohol / 수면정신생리

The use of alcohol is associated with the development and worsening of sleep disorder. Alcohol is generally known to have a sedative effect, but it has an arousal or sedative effect depending on the timing and drinking dose and directly affects REM sleep physiology. Alcohol acts on the central nervous system (CNS) to interfere with the sleep-wake cycle and to affect sleep-related hormone secretion. In addition, the ingestion of alcohol pre-sleep is associated with deterioration and development of sleep related breathing disorders (SBD). The increase in resistance of the upper respiratory tract and the decrease in sensitivity of the CNS respiratory center and the respiratory muscles are major mechanisms of alcohol-induced SBD, and result in snoring or apnea in healthy men or aggravating apnea in patients with OSA. Sleep-related restless leg syndrome and circadian rhythm disorders are common in alcohol use disorder patients. This review provides an assessment of scientific studies that investigated on the impact of alcohol ingestion on nocturnal sleep physiology and sleep disorders.

Microbiologic distribution and clinical features of nontuberculous mycobacteria in the tertiary hospital in Daegu / 영남의대학술지

BACKGROUND: Recent studies have shown that the nontuberculosis mycobacterium (NTM) recovery rate in clinical cultures has increased within Korea. However, another study conducted by a secondary hospital within Daegu reported different results. Therefore, the purpose of this study is to understand and evaluate the microbiological distribution and clinical features of NTM in Daegu. METHODS: A retrospective study was conducted on 11,672 respiratory specimens undergoing acid fast bacilli (AFB) culture from 6,685 subjects who visited Yeungnam University Respiratory Center from January 2012 to December 2013. RESULTS: Of the 11,672 specimens undergoing AFB culture, 1,310 specimens (11.2%) showed positive results. Of these specimens, NTM was recovered from 587 specimens, showing a recovery rate of 44.8%. Identification test for NTM was performed on 191 subjects; the results were as follows: M. avium-intracellulare complex (MAC) 123 (64.4%), M. abscessus 20 (10.5%), M. kansasii 12 (6.3%), and 33 other NTM germ strains. Of the 382 subjects with NTM, 167 were diagnosed with pulmonary NTM disease (43.7%), however virulence differed depending on NTM strain. Multivariate analysis showed that nodular bronchiectasis, the nodules, and finding consistent with cavity under imaging study were statistically significant for triggering pulmonary NTM disease. AFB culture showing MAC and M. abscessus was statistically significant as well. Positive predictive value for NTM polymerase chain reaction (NTM-PCR) was 88.6%. CONCLUSION: Results for NTM recovery rate within the Daegu area were similar to those for the Seoul metropolitan area. We can assume that NTM infection is increasing in our community, therefore AFB-positive subjects (1) should undergo NTM-PCR, (2) should have their culture results checked for differentiation of mycobacterium tuberculosis complex (MTB) from NTM, and (3) undergo NTM identification test to confirm its type. Administration of treatment with the above results should be helpful in improving the patients' prognosis.

Application of neurally adjusted ventilatory assist in preterm infants with respiratory distress syndrome / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To observe the effects of neurally adjusted ventilatory assist (NAVA) on the patient-ventilator synchrony, gas exchange, and ventilatory parameters in preterm infants with respiratory distress syndrome (RDS) during mechanical ventilation.</p><p><b>METHODS</b>Ten preterm infants with RDS received mechanical ventilation in NAVA mode for 60 minutes and in synchronized intermittent mandatory ventilation (SIMV) mode for 60 minutes, and the two modes were given in a random order. The vital signs, patient-ventilator synchrony, blood gas values, and ventilatory parameters were compared between the two ventilation modes.</p><p><b>RESULTS</b>Inspiratory trigger delay was significantly shorter with NAVA than with SIMV (P<0.05). There were no significant differences in arterial pH, PaCO2, PaO2 and PaO2/FiO2 between the two modes. The spontaneous respiratory rate, peak inspiratory pressure (PIP), electrical activity of the diaphragm and work of breathing were significantly lower in NAVA than in SIMV (P<0.05).</p><p><b>CONCLUSIONS</b>Compared with SIMV, NAVA appears to improve patient-ventilator synchrony, decrease PIP, and reduce diaphragmatic muscle load and work of breathing in preterm infants with RDS during mechanical ventilation.</p>

Phrenic Nerve Stimulation for Diaphragm Pacing in a Quadriplegic Patient

Chronic hypoventilation due to injury to the brain stem respiratory center or high cervical cord (above the C3 level) can result in dependence to prolonged mechanical ventilation with tracheostomy, frequent nosocomial pneumonia, and prolonged hospitalization. Diaphragm pacing through electrical stimulation of the phrenic nerve is an established treatment for central hypoventilation syndrome. We performed chronic phrenic nerve stimulation for diaphragm pacing with the spinal cord stimulator for pain control in a quadriplegic patient with central apnea due to complete spinal cord injury at the level of C2 from cervical epidural hematoma. After diaphragmatic pacing, the patient who was completely dependent on the mechanical ventilator could ambulate up to three hours every day without aid of mechanical ventilation during the 12 months of follow-up. Diaphragm pacing through unilateral phrenic nerve stimulation with spinal cord stimulator was feasible in an apneic patient with complete quadriplegia who was completely dependent on mechanical ventilation. Diaphragm pacing with the spinal cord stimulator is feasible and effective for the treatment of the central hypoventilation syndrome.

An Acute Postoperative Intractable Hyperventilation after an Endoscopic Third Ventriculostomy

This report describes a rare case of postoperative hyperventilation attack after an endoscopic third ventriculostomy in a 46-year-old woman. About 60 min after the termination of the operation, an intractable hyperventilation started with respiratory rate of 65 breaths/min and EtCO2, 16.3 mm Hg. Sedation with benzodiazepine, thiopental sodium, fentanyl, and propofol/remifentanil infusion was tried under a rebreathing mask at a 4 L/min of oxygen. With aggressive sedative challenges, ventilation pattern was gradually returned to normal during the 22 hrs of time after the surgery. A central neurogenic hyperventilation was suspected due to the stimulating central respiratory center by cold acidic irrigation solution during the neuroendoscopic procedure.

Damage effects of chronic hypoxia on medulla oblongata associated with oxidative stress and cell apoptosis / 生物医学工程学杂志

The aim of this study is to study the damage effects of chronic hypoxia on medulla oblongata and to explore whether the damage is associated with oxidative stress and cell apoptosis. Adult male SD rats were randomly divided into two groups: control group and chronic hypoxia group. Medulla oblongata was obtained for the following methods of analyses. Nissl's staining was used to examine the Niss bodies of neurons in medullary respiratory related nuclei, biochemistry methods were utilized to examine oxidant stress damage induced by chronic hypoxia on medulla oblongata through measuring malondialdehyde (MDA) content and superoxide dismutase (SOD) activity, and RT-PCR technique was used to study the influence of apoptosis induced by chronic hypoxia on medulla oblongata through analyzing the levels of Bax mRNA and Bcl-2 mRNA. The results showed the optical densities of Nissl's staining in pre-BötC, NA, NTS, FN, and 12N were significantly decreased in chronic hypoxia group in comparison with that in control group (P < 0.05). In chronic hypoxia group, MDA level was significantly higher than that in the control group (P < 0.05), whereas SOD level had no significant difference between the two groups (P > 0.05). Bax mRNA expression had no obvious change and Bcl-2 mRNA expression significantly decreased in chronic hypoxia group in comparison with that in control group (P < 0.05). The results suggest that chronic hypoxia could bring about serious damage to medullary respiratory centers through aggravating oxidative stress and increasing cell apoptosis.

Identification of major rice allergen and their clinical significance in children / 소아과

PURPOSE: Recently, an increase in the number of patients sensitized to rice allergen with or without clinical symptoms has been reported. This study was designed to determine the major allergens in rice and their clinical significance. METHODS: Twenty-four children (15 boys and 9 girls; mean age, 16.3 months) with allergic disease, who were sensitized to rice antigen (by UniCAP) in the Pediatric Allergy Respiratory Center at Soonchunhyang University Hospital, were enrolled in this study. The allergenicity of various types of rice (raw, cooked, and heat-treated, simulated gastric fluid [SGF], and simulated intestinal fluid [SIF]) was investigated using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoglobulin E (IgE) immunoblots. The patients' medical records, including laboratory data and allergy symptoms after ingestion of rice were reviewed. RESULTS: Patients were sensitized to an average of 13.5 food antigens and their mean total IgE was 6,888.7 kU/L. In SDS-PAGE, more than 16 protein bands were observed in the raw rice, whereas only 14-16 kDa and 31-35 kDa protein bands were observed in cooked rice. The common SDS-PAGE protein bands observed in SGF-, SIF-, and heat-treated rice were 9, 14, and 31 kDa. In a heated-rice IgE immunoblot, protein bands of 9, 14, and 31-33 kDa were found in 27.8%, 38.9%, and 38.9% of all sera, respectively, and in 50%, 50%, and 75%, of ser a from the 4 symptomatic patients, respectively. CONCLUSION: The 9-, 14-, and 31-kDa protein bands appeared to be the major allergens responsible for rice allergy symptoms.

Group II metabotropic glutamate receptors is involved in the modulation of respiratory rhythmical discharge activity in neonatal rat medullary brain slices / 南方医科大学学报

<p><b>OBJECTIVE</b>To explore the role of group II metabotropic glutamate receptors in the modulation of basic respiratory rhythm.</p><p><b>METHODS</b>Neonatal (0-3 days) SD rats of either sex were used. The medulla oblongata brain slice containing the medial region of the nucleus retrofacialis (mNRF) and the hypoglossal nerve rootlets was prepared, and the surgical procedure was performed in the modified Kreb's solution (MKS) with continuous carbogen (95% O2 and 5% CO2) within 3 min. The brain slices were quickly transferred to a recording chamber and continuously perfused with oxygen-saturated MKS at a rate of 4-6 ml/min at 27-29 degrees celsius. Eighteen medulla oblongata slices were divided into 3 groups and treated for 10 min with group II metabotropic glutamate receptor-specific agonist 2R,4R-4-aminopyrrolidine-2,4-dicarboxylate (APDC) (at concentrations of 10, 20, 50 micromol/L), group II metabotropic glutamate receptor antagonist (2S)-alpha-ethylglutamic acid (EGLU) (300 micromol/L), or APDC (50 micromol/L)+EGLU (300 micromol/L) after a 10 min APDC (50 micromol/L) application. Respiratory rhythmical discharge activity (RRDA) of the rootlets of the hypoglossal nerve was recorded by suction electrodes.</p><p><b>RESULTS</b>APDC produced a dose-dependent inhibitory effect on the RRDA, prolonging the respiratory cycle and expiratory time and decreasing the integral amplitude and inspiratory time. EGLU induced a significant decrease in the respiratory cycle and expiratory time. The effect of APDC on the respiratory rhythm was partially reversed by the application of APDC+EGLU.</p><p><b>CONCLUSION</b>Group II metabotropic glutamate receptors are probably involved in the modulation of the RRDA in isolated neonatal rat brainstem slice.</p>

A study of the frequency and characteristics of minor clinical manifestations in children with atopic dermatitis / 소아과

PURPOSE: We aimed to evaluate the frequency and characteristics of minor clinical manifestations of atopic dermatitis (AD) in Korean children to aid the diagnosis and treatment of AD. METHODS: From April 2007 to December 2007, we enrolled 106 children (aged 1 month [infants] to 15 years) diagnosed with AD at the Pediatric Allergy Respiratory Center in Soonchunhyang University Hospital. Clinical manifestations were examined and laboratory findings (total and specific immunoglobulin E [IgE] levels and peripheral blood eosinophil count) were analyzed and compared. RESULTS: Minor symptoms, in order of frequency, included xerosis (78.3%), aggravation due to environmental or emotional stress (43.4%), lichenification (35.8%), orbital darkening (34.0%), periauricular eczema (33.0%), and cutaneous infection (31.1%). Older children (> or =2 years) showed more orbital darkening (P=0.01), horizontal crease (P=0.01), and lichenification (P=0.001) than infants. Patients with severe AD (scoring atopic dermatitis [SCORAD] score, > or =40) showed higher frequencies of xerosis (P=0.04), cutaneous infection (P=0.03), ichthyosis (P=0.18), keratosis pilaris (P=0.02), pityriasis alba (P=0.07), recurrent conjunctivitis (P=0.02), orbital darkening (P=0.001), aggravation due to environmental or emotional stress (P=0.05), facial eczema (P=0.001), lichenification (P=0.001), and hand/foot eczema (P=0.04) than those with mild-to-moderate AD. Children with atopic eczema showed more facial eczema (P=0.01) and lichenification (P=0.04) than those with non-atopic eczema. CONCLUSION: The clinical manifestations of AD were similar to those established by Hanifin and Rajka. However, we need to develop our own diagnostic criteria for AD, because the frequencies shown by our subjects differed from those observed in other countries.

Identification and classification of respiratory pacemaker neurons in the medial region of nucleus retrofacialis in neonatal rats / 生理学报

The aim of the present study is to supply direct experimental proof that the medial region of nucleus retrofacialis (mNRF) is the site generating basic rhythm of respiration. Medullary slices of neonatal Sprague-Dawley rats, including hypoglossal nerve root and mNRF, were made according to Suzue's method. Simultaneous recordings of the respiratory rhythmic discharge activity (RRDA) in hypoglossal nerve root with suction electrode and the respiratory neuronal discharge in the mNRF with whole cell patch clamp were performed on the brainstem slice in vitro. Not only the electrophysiological characteristics of pacemaker and non-pacemaker neurons, but the cadmium-sensitivity of pacemaker neurons was observed. The nature of the discharge in the respiratory pacemaker neurons in mNRF was spontaneous, rhythmical and voltage-dependent burst behavior, generating an ectopic burst in response to a depolarizing or hyperpolarizing current. There were no significant differences in capacitance of membrane (C(m)), input resistance of membrane (R(m)) and leak inward current (I(leak)) between the pacemaker neurons and the non-pacemaker ones. Moreover, most pacemaker neurons in the mNRF were Cd(2+)-insensitive. In conclusion, these results support the idea that the mNRF is the site generating basic respiratory rhythm.

Clinical Investigation of Children with Severe Atopic Dermatitis / 소아알레르기및호흡기학회지

PURPOSE: We attempted to investigate clinical characteristics of children with severe atopic dermatitis. METHODS: A total of 204 children diagnosed with Atopic dermatitis at the Pediatric Allergy Respiratory Center in Busan St. Mary's Medical Center from June 2006 to June 2008 were enrolled in this study. Cases were divided into 3 groups according to SCORAD index: severe, moderate and mild groups. We collected birth, environment, and allergic family history, and tested serum IgE, total eosinophil count, specific IgE, ECP (Eosinophil Cationic Protein) and the SCORAD index between the 3 groups. RESULTS: Of the 204 patients, 100 (49.02%) were included in the severe group, 51 (25.0%) in the moderate group, and 53 (25.98%) in the mild group. There were no differences in serum total IgE, serum total eosinophil counts and ECP between the severe and moderate groups. Serum total IgE, serum total eosinophil counts and ECP were relatively higher in the severe group than mild group. Food allergen sensitization rate was relatively higher in the infantile severe group than in the childhood severe group, while inhalant allergen sensitization rate was relatively higher in the childhood severe group than in the infantile severe group. There was no correlation between serum total IgE, serum total eosinophil counts, ECP and the number of sensitized allergens relative to SCORAD index in the severe group. CONCLUSION: Serum IgE, total eosinophil count, specific IgE and ECP may be specific indicators of children with severe atopic dermatitis. Further studies are needed to determine a clear distinction between severe and moderate atopic dermatitis patients.

Comparison of Clinical Severity and Laboratory Results between Atopic and Non-atopic Eczema in Children / 소아알레르기및호흡기학회지

PURPOSE: We aim to compare clinical severity of atopic and non-atopic eczema in children and examine the relationship between total-IgE, eosinophil counts, Eosinophil, Eosinophil cationic protein (ECP) and clinical severity of atopic dermatitis (AD). METHODS: A total of 271 children diagnosed with AD at the Pediatric Allergy Respiratory Center in Soonchunhyang University Hospital from October 2005 to March 2008 were enrolled for this study and divided into 2 groups: atopic and non-atopic eczema. Serum concentrations of total- and specific-IgE, eosinophil counts and ECP were measured. Allergy skin tests were also performed and the SCORAD index was used to evaluate clinical severity. Comparisons the SCORAD index and serum total-IgE, eosinophil count and ECP between the 2 groups were made. RESULTS: Of the 271 patients, 162 (59.8%) were included in the atopic eczema group, while 109 (40.2%) were included in the non-atopic group according to the laboratory results. Serum total- IgE, eosinophil counts, ECP, the SCORAD index and the frequency of a family history of eczema were relatively higher in the atopic group. In the atopic group, serum total-IgE, eosinophil counts and ECP each had a statistically significant correlation with the SCORAD index with eosinophil counts showing the highest correlation. However, only eosinophil counts had a statistically significant correlation with the SCORAD index in the non-atopic group. CONCLUSION: Serum total-IgE, eosinophil counts, and ECP can be used as markers for clinical severity in patients with atopic eczema, while eosinophil counts be used as marker for clinical severity in those with non-atopic eczema.

GABA A receptor participates in respiratory enhancement induced by nikethamide in neonatal rats / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the role of GABA A receptor in nikethamide-induced respiratory enhancement in the medullary slices of neonatal rats.</p><p><b>METHODS</b>Ex vivo medullary slices of neonatal rats (1 to 3 days old) containing the medial region of the nucleus retrofacialis with the hypoglossal nerve rootlets were prepared and perfused with modified Kreb's solution to record respiration-related rhythmic discharge activity (RRDA) from the hypoglossal nerve rootlets using suction electrodes. Thirty RRDA-positive slices were randomized into 5 equal groups and perfused with nikethamide (at concentrations of 0.5, 1, 3, 5, 7, and 10 microg/ml with the optimal nikethamide concentration determined), GABA (at 10, 20, 40, and 60 micromol/ to determine the optimal concentration), 10 micromol/ bicuculline, 10 micromol/ bicuculline plus 40 micromol/L GABA, and 5 microg/ml nikethamide followed by 5 microg/ml nikethamide plus 10 micromol/ bicuculline after wash out, respectively.</p><p><b>RESULTS</b>Nikethamide increased RRDA at the concentrations of 0.5-7 microg/ml, and 5 microg/ml nikethamide showed the most distinct effect on the inspiratory time (TI), integral amplitude (IA), and respiratory cycle (RC). GABA at 40 micromol/ showed the most effective inhibition of RRDA in terms of TI, IA, and RC. Bicuculline at 10 micromol/ could increase the IA, TI and RC, but the combination of 10 micromol/ bicuculline and 40 micromol/ GABA had no significant effects on RRDA. Compared with nikethamide used alone, nikethamide plus bicuculline significantly increased TI and IA without affecting RC.</p><p><b>CONCLUSION</b>Nikethamide can enhance RRDA of the hypoglossal nerve rootlets in the medullary slices of neonatal rats, and the effect can be partially mediated by the GABA A receptor.</p>

Glycine is involved in the modulation of respiratory rhythmical discharge activity in neonatal rat medullary brain slices / 南方医科大学学报

<p><b>OBJECTIVE</b>To determine the role of glycine (Gly) in the generation and modulation of basic respiratory rhythm.</p><p><b>METHODS</b>Neonatal (0-3 days) SD rats of either sex were used in this study. The medulla oblongata brain slice containing the medial region of the nucleus retrofacialis (mNRF) and the hypoglossal nerve rootlets was prepared, and the surgical procedure was performed in the modified Kreb's solution (MKS) with continuous carbogen (95% O(2) and 5% CO(2)) within 3 min. The rhythmical respiratory discharge activity (RRDA) of the hypoglossal nerve rootlets was recorded using suction electrode. Eighteen medulla oblongata slice preparations were divided into 3 groups and treated for 20 min with Gly receptor specific agonist Gly (10 micromol/L), Gly receptor antagonist strychnine (STR, 1 micromol/L), or Gly+STR after a 20 min Gly application. The changes in RRDA of the hypoglossal nerve rootlets were observed.</p><p><b>RESULTS</b>Gly significantly decreased the inspiratory time and integral amplitude (IA), but the changes of respiratory cycle (RC) and expiratory time (TE) were not statistically significant. STR induced a decrease in expiratory time and respiratory cycle without significantly affecting the inspiratory time or integral amplitud. The effect of Gly on the respiratory rhythm was partially reversed by additional application of STR.</p><p><b>CONCLUSION</b>Gly may play an important role in the modulation of RRDA in the medulla oblongata slice of neonatal rats.</p>

Role of 5-HT(2A) receptor in increase in respiratory-related rhythmic discharge activity by nikethamide in neonatal rat transverse medullary slices / 生理学报

To investigate the effects of nikethamide on the generation and modulation of rhythmic respiration of neonatal rats and the role of 5-HT(2A) receptor in this course, experiments were performed on the transverse medullary slices of neonatal rats (both sexes, 1-3 d) in vitro. The slices containing the medial region of the nucleus retrofacialis (mNRF) with the hypoglossal nerve rootlets were prepared in which the respiratory-related rhythmic discharge activity (RRDA) was recorded from the hypoglossal nerve rootlets by suction electrode. The possible role of nikethamide on RRDA was investigated by administration of an agonist of 5-HT(2A) receptor, 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI), and an antagonist of 5-HT(2A) receptor, ketanserine, dissolved in modified Krebos solution (MKS). Thirty slices were randomly divided into five groups: Group 1: the slices were perfused with different concentrations of nikethamide (0.5, 1, 3, 5, 7, 10 μg/mL), and the most effective concentration was selected; Group 2: the slices were perfused with DOI (40 μmol/L); Group 3: the slices were perfused with ketanserine (40 μmol/L); Group 4: the slices were perfused with ketanserine + DOI; Group 5: the slices were perfused with nikethamide, then perfused with nikethamide + ketanserine after washout of nikethamide. Nikethamide increased RRDA in transverse medullary slices at 0.5-7 μg/mL, and 5 μg/mL was the most effective concentration. DOI increased RRDA with prolonged inspiratory time (TI), increased integral amplitude (IA), and shortened respiratory cycle (RC). Ketanserine decreased RRDA with shortened TI, decreased IA and prolonged RC. Ketanserine + DOI had no significant effects on RRDA. The effects of nikethamide on RC and IA were totally and partially reversed by additional application of ketanserine, but the effect of nikethamide on TI was not influenced by ketanserine. It is proposed that nikethamide increases RRDA partly via 5-HT(2A) receptors.

Role of 5-HT2A-receptors coupled with superoxide anion in the medial area of nucleus retrofacialis / 南方医科大学学报

<p><b>OBJECTIVE</b>To explore the effect of 5-HT2A-receptors coupled with superoxide anion (O2-) on respiratory regulation signal transductionin passageway in the medial area of nucleus retrofacialis (mNRF).</p><p><b>METHODS</b>mNRF island was prepared from medullary slices of neonatal SD rats according to Johnson's method and transferred separately into 24-well culture plates with reagents according to protocol, followed by incubation for 60 min at 37 degrees C in a humidified incubator with 5% CO2. Absorbance of 100 microl supernatant was measured by spectrophotometry at 550 nm and the effect of 5-HT and 2,5-dimethoxy-4-iodoamphetamine hydrochloride (DOI, agonist of 5-HT2A-receptors) on O2- generation in the mNRF was observed, along with the inhibition of this effect by ketanserin (antagonist of 5-HT2A-receptors) and alpha-lipoic acid (alpha-LA, a antioxidant).</p><p><b>RESULTS</b>5-HT concentration-response curve demonstrated that absorbance peak occurred at 1 micromol/L without further increment with higher concentration. DOI concentration-response curve showed the absorbance peak at 20 micromol/L without further increment. 5-HT and DOI significantly increased the absorbance with comparable effects. Ketanserin and alpha-LA significantly decreased the absorbance generated by 5-HT and DOI.</p><p><b>CONCLUSION</b>Activation of 5-HT2A receptors results in obvious O2- production in mNRF, suggesting that 5-HT2A receptors regulate respiratory function in association with O2-.</p>

Risk Factors for Persistent Wheezing in Infants with Recurrent Wheezing / 소아알레르기및호흡기학회지

PURPOSE: The purpose of our study was to investigate the risk factors in developing persistent wheezing in infants with recurrent wheezing. METHODS: Two hundred thirty two infants with recurrent wheezing under two years old visited to Pediatric Allergy and Respiratory Center in Soonchunhyang University Hospital from August 1998 to May 2002 were enrolled and investigated until May 2006, retrospectively. The patients were divided into two groups; persistent wheezer group (PW) who had recurrent wheezing until six years old and transient wheezer group (TW) who didn't have wheezing after three years old. The patients' demographics and laboratory data such as serum total IgE, specific IgE (Dp, Df, dog hair, egg white, milk, soy) and peripheral blood eosinophil count at the first visit were analysed to investigate the risk factors for developing persistent wheezing. RESULTS: PW was 115 (49.5%) and TW was 117 (50.5%) out of 232 infants with recurrent wheezing. In comparison analysis between PW and TW, there were no significant differences in age (months), serum total IgE, peripheral blood eosinophil (P=0.319), birth weight, and gestational age. However, increased serum total IgE (OR 1.72; 95% CI 1.01-2.90), sensitization to Dp (3.6, 1.14-11.39) and egg white (2.96, 1.49-5.89), family history of allergic diseases (2.35, 1.33-4.13), personal history of atopic dermatitis (2.08, 1.11-3.89), and not having older siblings (2.93, 1.64-5.24) had statistic significance. Among these results, not having older sibling (adjusted OR 2.74, 1.46-5.13) and having family history of allergic diseases (adjusted OR 2.69, 1.39-5.18) had strong significance by regnession a nalysis. CONCLUSION: Early intervention of infants with high risk factors for developing persistent wheezing may improve their outcome. Therefore early intervention of infants with high risk factors will be necessary for preventing develop childhood asthma.

The Prior Symptoms in Children Hospitalized with Acute Asthma Exacerbation / 소아알레르기및호흡기학회지

PURPOSE: Several studies have suggested that many children have no symptoms before hospitalization with asthma exacerbations. The purpose of this study was to evaluate how many asymptomatic children were hospitalized for asthma exacerbation, and to analyze their prior symptoms. METHODS: Children over 3 years old, hospitalized for acute asthma exacerbation in the Pediatric Allergy and Respiratory Centers in the Kangnam St. Mary's Hospital from January 2003 to December 2006 were enrolled, and their medical records reviewed retrospectively. RESULTS: Among 142 identified patients (median age 5+/-2.5 yr), the group who developed asthmatic symptoms within four weeks before admission occupied about 18.5%. And the group who developed asthmatic symptoms in four weeks or acute exacerbation in six weeks before admission occupied about 23.2%. And group who had asthmatic symptoms in four weeks or acute exacerbation in six weeks or acute exacerbation one year before admission occupied about 31.6%. In September, the group who had no symptom before admission was larger than the group who had asthmatic symptom. The baseline characteristics of each group were not significantly different with respect to age, sex, past history or family history of allergic disease, UniCAP, total IgE and eosinophil count. CONCLUSION: Many children had no symptoms before admission for acute asthma exacerbation. Therefore, we suggest considering that a large number of patients with no previous symptoms are at great risk of acute exacerbation in September, when maintenance therapy is determined.