Effectiveness of a positive expiratory pressure device in conjunction with beta2-agonist nebulization therapy for bronchial asthma

Patients with asthma often show increased airway hyperreactivity and mucus hypersecretion. Although beta2-agonist therapy is one of the most common and effective ways used to relieve airway obstruction, the use of a positive expiratory pressure device (PEPD) is also effective in mucus clearance. However, no previously reported study has examined the effectiveness of these two therapies used in combination. This study assessed the effectiveness of a PEPD on beta2-agonist nebulization therapy by measuring the pulmonary function before and after nebulization therapy in 54 asthmatic patients. The results show that the use of PEPD after beta2-agonist nebulization therapy improved pulmonary function compared with the use of beta2-agonist nebulization therapy alone, as shown by the increases in forced midexpiratory flow and forced vital capacity (FVC). Patients with forced expiratory volume in 1 sec (FEV1) below 85% FVC obtained a significant improvement in FEV1 and FVC after using PEPD. When PEPD was used before beta2-agonist nebulization therapy, there were no obvious direct bronchodilative effects. The use of PEPD after beta2-agonist therapy, however, significantly enhanced the bronchodilative effect of beta2-agonist therapy in patients with an FEV1 below 85% FVC. The additional effect of PEPD use in improving pulmonary function after beta2-agonist nebulization therapy might be a result of an enhancement in mucus clearance.

Familial Mediterranean fever in a Taiwanese patient

Familial Mediterranean fever is a rare disease characterized by cyclic attacks of fever, serositis and strong family background. Here we report a 22-year-old man who suffered from recurrent fever accompanied by chest and abdominal pain for more than 10 years. The attack frequency was about once per 2-3 weeks. Although he consulted many clinics and even received appendectomy at the age of 15, no definite diagnosis was given. During the admission, many laboratory examinations failed to show any abnormality except mild leukocytosis and elevated C-reaction protein. Image studies including chest X ray and abdominal CT scan showed negative result but, interestingly, Gallium-67 scan showed a hot spot in right lower chest and right lower abdomen. After prophylaxis with colchicine 1.0 mg per day, he has enjoyed more than 2 years without the above symptoms.

Enhanced prostaglandin E2 secretion in sputum from asthmatic patients after zafirlukast therapy

BACKGROUND AND PURPOSE

Leukotrienes are important inflammatory mediators of bronchial asthma that cause bronchoconstriction, mucous secretion, and increased vascular permeability. Current guidelines recommend anti-leukotriene agents as alternative treatments for asthma; however, data on their anti-inflammatory effect is lacking.

METHODS

The purpose of this study was to determine the anti-inflammatory effect of zafirlukast, a leukotriene antagonist, in patients with bronchial asthma. A total of 30 adult patients with mild persistent asthma received 6 weeks of zafirlukast treatment. Peak expiratory flow rate (PEFR) was determined before and after therapy to assess clinical efficacy. Both serum and sputum samples were collected before and after therapy and concentrations of eosinophil cationic protein (ECP), prostaglandin E2 (PGE2), and leukotriene E4 (LTE4) were measured.

RESULTS

A significant improvement in PEFR was found after zafirlukast therapy (p = 0.017). There was also a significant reduction in serum ECP concentration (13.6 +/- 2.4 micrograms/L vs 10.3 +/- 2.1 micrograms/L, p < 0.025) and a significant increase in sputum PGE2 concentration (112.7 +/- 14.0 pg/mL vs 176.8 +/- 32.1 pg/mL, p < 0.01). The percentage eosinophil count and the concentrations of ECP and LTE4 in the sputum were not significantly different after therapy.

CONCLUSION

This study found a significant reduction in serum ECP and a significant increase in sputum PGE2 concentrations in asthmatic patients after zafirlukast treatment, both of which were significantly associated with improvement in PEFR. The modulation of PGE2 and ECP production might occur through the anti-inflammatory effect of zafirlukast.

Effects of BCG on ovalbumin-induced bronchial hyperreactivity in a guinea pig asthma model

To test the effects of Bacillus Calmette-Guérin (BCG) on ovalbumin (OVA)-induced airway hyper-reactivity in guinea pigs, a total of 40 young guinea pigs was individually vaccinated subcutaneously with 0.2 mL of 2% OVA, 50 microg BCG, or a mixture of OVA and BCG (OVA+BCG). Airways were sensitized using nebulization with 1% OVA for 3 min once a week for two applications, followed by 2% OVA nebulized challenge for 3 min 1 week after the last application. Different concentrations of methacholine were used to detect airway hyperreactivities. At the third week, the guinea pigs were nebulized with either methacholine or OVA to test airway hyperreactivity. The OVA-vaccinated group presented with severe airway hyperresponsiveness after OVA and methacholine challenges; the BCG-vaccinated group showed mild airway hyperreactivity; and the OVA+BCG group showed the least amount of airway hyperreactivity. Lung histopathology in all groups, except the OVA+BCG-vaccinated group, showed severe thickening of the alveolar walls which became firmly fibrotic, and narrowing of the alveolar spaces was also noted. The guinea pigs in the OVA+BCG-vaccinated group had similar pulmonary morphology with that of naive guinea pigs, and had mild cell infiltration in the alveolar wall. The results of the skin biopsies at 6 h (2% OVA, 0.05 mL) and 36 h (20 microg PPD, 0.05 mL) after purified protein derivative (PPD) inoculation showed that infiltration of eosinophils and activation of CD4+ T-cells occurred in the OVA-vaccinated group. In the BCG-vaccinated groups, infiltration of CD4+ T-cells, CD8+ T-cells and macrophages occurred. OVA-specific IgG2 increased in the BCG-vaccinated groups after OVA-induced airway hyperreactivity occurred. The peripheral cell subpopulation showed that there was obviously increased activation of CD4+ and CD8+ T-cells in the OVA+BCG-vaccinated group. The phagocytic activity of macrophages also increased in both BCG- and OVA+BCG-vaccinated groups. The prevention of OVA-induced airway hyperreactivities using BCG vaccination in conjugation with OVA in these young guinea pigs indicated that it might be a good approach to avoid allergic reactions in humans.

Temporal trends and molecular epidemiology of HIV-1 infection in Taiwan from 1988 to 1998

Eight hundred and seventy-nine HIV-1-infected patients (comprising 46% of reported HIV-1/AIDS cases in Taiwan) were recruited for this study of the molecular epidemiology of HIV-1 in Taiwan from 1988 to 1998. HIV-1 subtypes were determined using a modified peptide-enzyme immunoassay complemented with DNA sequencing and phylogenetic analysis. Of the 807 HIV-1 infected men, 68.2% were infected with HIV-1B, 29.5% with HIV-1 circulating recombinant form (CRF)01_AE and 2.3% with other subtypes. Of the 72 HIV-1-infected women, 72.2% were infected with HIV-1 CRF01_AE, 13.9% with HIV-1B, and 13.9% with other subtypes. All of 8 foreign-born, Southeast Asian women and 6 of 7 (85.7%) Taiwan-native female commercial sex workers were infected with HIV-1 CRF01_AE. Fourteen of the 33 (42.4%) heterosexual married men with CRF01_AE had transmitted HIV-1 to their wives, whereas only 1 of 17 (5.9%) men with HIV-1 B had transmitted HIV-1 to their spouses (p < .01). Of 18 heterosexual male injecting drug users, 1 of 12 (8.5%) with HIV-1B and 5 of 6 (83.3%) with HIV-1 CRF01_AE had had sexual contact with female commercial sex workers (p < .01). Therefore, in this population, CRF01_AE was preferentially associated with heterosexual risk groups, a finding compatible with differences in transmission capability between B and non-B subtypes.

Efficacy of zafirlukast in the treatment of patients with bronchial asthma

Zafirlukast is a drug newly used for the treatment of asthma. In this study, we examined the efficacy of zafirlukast on asthmatic patients and compared this efficacy between patients in different age groups and with different severities of pulmonary function. Patients concurrently inhaled long-acting beta2-agonist, corticosteroid or taken an oral aminophylline regimen, were treated with 20 mg oral zafirlukast twice daily for 6 weeks. In total, 32 asthmatic patients were included in the study. The primary efficacy measures included morning and evening peak expiratory flows (PEFs); secondary efficacy measures were the scoring of asthma symptoms including sleeping, coughing, and wheezing scores. Pulmonary functions including forced expiratory flow in 1 sec (FEV1), forced vital capacity (FVC), and PEF rate (PEFR) were examined during each clinical visit. Results showed that oral zafirlukast administration resulted in improvements in morning and evening PEFs and asthma symptom scores with the following statistical p values: morning PEF (285.8 vs 308.4 L/min), p = 0.003; evening PEF (293.3 vs 312.1 L/min), p = 0.007; coughing score (1.03 vs 0.72), p = 0.011; and wheezing score (0.71 vs 0.51), p = 0.009. As to the pulmonary function during the clinical visit, only the improvement of PEFR reached a statistically significant level (74.3 vs 82, p = 0.017). We compared the efficacy between asthmatic patients of different ages and those with different severities of pulmonary function. In patients aged below 50 years, those with FEV1 above 80% of the predicted value and FVC above 85% of the predicted value were more responsive to zafirlukast. In conclusion, we demonstrate the efficacy of zafirlukast in asthma therapy particularly for those patients who are younger and have better pulmonary function. When asthmatic patients do not respond to inhaled corticosteroid, long-acting beta2-agonist, or oral aminophylline, zafirlukast may provide an adjunct effect for asthma therapy.

Identification of vacuolar serine proteinase as a major allergen of Aspergillus fumigatus by immunoblotting and N-terminal amino acid sequence analysis

Aspergillus species are common airborne fungi that have been identified as causative agents of extrinsic bronchial asthma. More than 10 allergens from A. fumigatus have been recently characterized by cDNA cloning. The objective of this study is to identify A. fumigatus allergens through immunoblot analysis using sera from asthmatic patients. IgE-binding components of A. fumigatus and IgE cross-reactivity among allergens of different prevalent airborne fungal species were analysed by immunoblot and immunoblot inhibition, respectively, using sera from asthmatic patients. The N-terminal amino acid sequences of major allergens identified were determined by Edman degradation. Among two batches (70 and 41 sera) of asthmatic sera tested, 19 (27%) and 14 (34%), respectively, have IgE immunoblot reactivity towards components of A. fumigatus. A 34-kDa protein that reacts with IgE antibodies in 15 (79%) and 11 (79%) of the 19 and 14 positive samples, respectively, may be considered a major allergen of A. fumigatus. The N-terminal amino acid sequences of the 34 kDa major allergen and the 30.5 and 30 kDa IgE-binding components of A. fumigatus showed sequence identity to that of the vacuolar serine proteinase from A. fumigatus. The results from immunoblot inhibition show IgE cross-reactivity among major allergens of A. fumigatus, P. notatum and P. oxalicum. Results obtained suggest that the 34 kDa major allergen of A. fumigatus may be a vacuolar serine proteinase. There is IgE cross-reactivity among serine proteinase allergens of A. fumigatus, P. notatum and P. oxalicum.

Cerebral and oculorhinal manifestations of a limited form of Wegener's granulomatosis with c-ANCA-associated vasculitis

The authors report on cerebral and oculorhinal manifestations in a patient with a cytoplasmic pattern of antineutrophil cytoplasmic autoantibody (c-ANCA)-associated vasculitis. Recurrent Tolosa-Hunt syndrome, cavernous sinus syndrome, Raeder's paratrigeminal neuralgia, and seizures were the major clinical manifestations. Brain MRI showed localized enhancing lesions initially in the cavernous sinus and later in the convexity pachymeninges. The lesions disappeared following 9 months of oral prednisolone (15 mg/day) and cyclophosphamide (100 mg/day) therapy. The presence of c-ANCA, demonstration of vasculitis, and depositions of immunoglobulin G (IgG) and fibrinogen in the vessel walls of pachymeninges of the patient confirmed an immune-mediated cause of the vasculitis. Cranial pathology without renal and pulmonary involvement suggests a variant of Wegener's granulomatosis, which is called the "limited" form of Wegener's granulomatosis. MRI, Raeder's paratrigeminal neuralgia, localized pachymeningitis.

Noncompetitive inhibition of the glycine receptor-mediated current by melatonin in cultured neurons

The effect of melatonin on the glycine receptor-mediated response was studied in cultured chick spinal cord neurons using the whole-cell voltage-clamp recording technique. Melatonin rapidly and reversibly inhibited the glycine-induced current in a dose-dependent fashion, with an EC(50) of 934 microM and a maximal inhibition of 100%. Furthermore, melatonin noncompetitively inhibited the glycine response by an agonist-independent mechanism that was distinct from that of an open-channel blocker.

Neither occlusion constraint nor binocular disparity accounts for the perceived depth in the 'sieve effect'

Current notions of binocular depth perception include (1) neural computations that solve the correspondence problem and calculate retinal positional disparity, and (2) recovery of ecologically valid occlusion relationships. The former framework works well for stimuli with unambiguous interocular correspondence, but less so for stimuli without well-defined disparity cues. The latter framework has been proposed to account for the phenomenon of perceived depth in stimuli without interocular correspondence, but its mechanism remains unclear. In order to obtain more insight into the mechanism, we studied the depth percept elicited by a family of stereograms - 'sieve' stimuli, adapted from Howard (1995) [Perception, 24, 67-74] - with interocular differences but no well-defined positional disparity cue. The perceived depth was measured by comparison to references at various depths established by standard retinal disparity and was consistently found to lie behind the fixation plane. Moreover, the magnitude of the depth percept depended on both the horizontal and vertical spatial characteristics of the stimulus in ways that were at odds with constraints of occlusion geometry. In comparison to the depth percept elicited by stimuli with well-defined disparity cues, the precision of the percept from the sieve stimuli was 10-20 times worse, suggesting that a different underlying computation was involved. Thus, neither of the above frameworks accounts for the depth percept arising from these stimuli. We discuss implications of our results for physiologically based computations underlying binocular depth perception.

Transient removal of extracellular Mg(2+) elicits persistent suppression of LTP at hippocampal CA1 synapses via PKC activation

Previous work has shown that seizure-like activity can disrupt the induction of long-term potentiation (LTP). However, how seizure-like event disrupts the LTP induction remains unknown. To understand the cellular and molecular mechanisms underlying this process better, a set of studies was implemented in area CA1 of rat hippocampal slices using extracellular recording methods. We showed here that prior transient seizure-like activity generated by perfused slices with Mg(2+)-free artificial cerebrospinal fluid (ACSF) exhibited a persistent suppression of LTP induction. This effect lasted between 2 and 3 h after normal ACSF replacement and was specifically inhibited by N-methyl-D-aspartate (NMDA) receptor antagonist D-2-amino-5-phosphovaleric acid (D-APV) and L-type voltage-operated Ca(2+) channel (VOCC) blocker nimodipine, but not by non-NMDA receptor antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX). In addition, this suppressive effect was specifically blocked by the selective protein kinase C (PKC) inhibitor NPC-15437. However, neither Ca(2+)/calmodulin-dependent protein kinase II inhibitor KN-62 nor cAMP-dependent protein kinase inhibitor Rp-adenosine 3', 5'-cyclic monophosphothioate (Rp-cAMPS) affected this suppressive effect. This persistent suppression of LTP was not secondary to the long-lasting changes in NMDA receptor activation, because the isolated NMDA receptor-mediated responses did not show a long-term enhancement in response to a 30-min Mg(2+)-free ACSF application. Additionally, in prior Mg(2+)-free ACSF-treated slices, the entire frequency-response curve of LTP and long-term depression (LTD) is shifted systematically to favor LTD. These results suggest that the increase of Ca(2+) influx through NMDA channels and L-type VOCCs in turn triggering a PKC-dependent signaling cascade is a possible cellular basis underlying this seizure-like activity-induced inhibition of LTP.

Neurocognitive attention and behavior outcome of school-age children with a history of febrile convulsions: a population study

PURPOSE

A prospective population-based case-control study was performed to ascertain whether febrile convulsion (FC) in early childhood is associated with neurocognitive attention deficits in school age.

METHODS

A total of 103 children, confirmed to have FC by age 3 years from a population survey of 4,340 live-birth newborns in Tainan City, Taiwan, was followed up until at least age 6 years. An achievement test, behavioral ratings, and computerized neurocognitive battery assessing various subcomponents of attention were given to 87 FC children (FC group) and 87 randomly selected population-matched control (CC group).

RESULTS

Compared with the CC group, the FC group did not have scholastic performance or behavioral outcome disadvantage. Overall FC group performance was distinguished by significantly higher scores in the achievement test and fewer missing errors (p < 0.005) and commission errors (p < 0. 05), less variability in reaction time (p < 0.005), and a nonsignificant trend of impulsivity. Attention performance of the FC and CC groups were comparable. Within the FC group, age at onset, complex FC, recurrence of FC, development of unprovoked seizures, or prior use of phenobarbital had no adverse effects on neurocognitive attention outcome.

CONCLUSIONS

This population study suggests that FC in early childhood does not have adverse effects on behavior, scholastic performance, and neurocognitive attention. On the contrary, the FC group demonstrated significantly better control of distractibility and attention at school age.

Purification of group 2 Dermatophagoides pteronyssinus allergen and prevalence of its specific IgE in asthmatics

Group 2 allergens are a major cause of sensitization in patients allergic to house dust mites. This study was performed to determine the prevalence of hypersensitivity to group 2 allergens (Der p 2) of Dermatophagoides pteronyssinus (Dp) in asthmatic patients in Taiwan. To facilitate the analysis of Der p 2-specific IgE, we raised a panel of monoclonal antibodies (MoAbs) to Der p 2 antigens. Purified Der p 2 was obtained after MoAb affinity column purification. There were 82 asthmatic patients (41 adults and 41 children) with hypersensitivity to Dp who were analyzed for hypersensitivity to Der p 2. All of them were both skin test- and serology test-reactive to Dp. Using purified Der p 2, 87.8% (72/82) of patients had a skin-test-positive reaction. Six adults (6/41) and 4 children (4/41) had negative skin tests for Der p 2. Ten families (both parents and children were asthmatics) of the 82 patients were selected for Der p 2 skin testing and Der p 2-specific IgE determination using immunoblot analysis. Results showed that 90% (18/20) of patients' skin reactions to Der p 2 and serum contained specific IgE to Der p 2. Because 87.8% (85.4% of adults and 90.2% of children) of the asthmatic patients with Dp hypersensitivity were allergic to Der p 2, its role in the pathogenesis of asthma in Taiwan appears to be important. Purified Der p 2 allergens can be further used for allergen skin testing and immunotherapy.

Identification and expression of an allergen Asp f 13 from Aspergillus fumigatus and epitope mapping using human IgE antibodies and rabbit polyclonal antibodies

The Aspergillus genus of fungi is known to be one of the most prevalent aeroallergens. On two-dimensional immunoblotting using patients' sera containing IgE specific for Asp f 13, an allergen with a molecular mass of 33 kDa and a pI of 6.2 was identified. This allergen was also present in A. fumigatus culture filtrates. Furthermore, the sequence of the Asp f 13 cDNA was identical to that for alkaline protease isolated from A. fumigatus and showed 42-49% identity of amino acids with two proteases from P. cyclopium and T. album and with the Pen c 1 allergen from P. citrinum. Asp f 13 coding sequences were expressed in Escherichia coli as a [His](6)-tagged fusion protein which was purified by Ni(2+)-chelate affinity chromatography. Recombinant Asp f 13 was recognized by rabbit polyclonal antibodies against Asp f 13 and by IgE antibodies from subject allergic to A. fumigatus. To identify and characterize the linear epitopes of this allergen, a combination of chemical and enzymatic cleavage and immunoblotting techniques, with subsequent N-terminal sequencing and mass spectrometry, were performed. At least 13 different linear epitopes reacting with the rabbit anti-Asp f 13 antiserum were identified, located throughout the entire molecule. In contrast, IgE from A. fumigatus-sensitive patients bound to three immunodominant epitopes at the C-terminal of the protein.

The Chinese herbal medicine Chai-Hu-Long-Ku-Mu-Li-Tan (TW-001) exerts anticonvulsant effects against different experimental models of seizure in rats

We evaluated the anticonvulsant effect of Chai-Hu-Long-Ku-Mu-Li-Tan (TW-001), a Chinese herbal medicine, and its mechanisms in several standard rodent models of generalized seizure. TW-001 (4 g/kg, p.o.) significantly increased the threshold for tonic electroconvulsions and the threshold for tonic seizures in response to i.v. infusion of pentylenetetrazole (PTZ). In the s.c. PTZ seizure test, both the incidence and severity of seizures were decreased by TW-001. TW-001 (1-10 mg/ml) did not alter resting membrane potential or input resistance of the hippocampal CA1 neurons, but elicited a reversible suppression of stimulus-triggered epileptiform activity in area CA1 and spontaneously occuring epileptiform burst discharges in area CA3 elicited by picrotoxin. Both field excitatory postsynaptic potentials and population spikes were reversibly depressed by TW-001 (0.5-15 mg/ml) in a concentration-dependent manner. The sensitivity of postsynaptic neurons to a glutamate-receptor agonist, alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid or N-methyl-D-aspartate, was not altered by TW-001 (10 mg/ml). However, TW-001 (5 mg/ml) clearly increased the magnitude of paired-pulse facilitation. TW-001 (5-10 mg/ml) reversibly limited the repetitive firing and reduced the maximal rate of rise of action potentials elicited by injection of depolarizing current pulses (0.4 nA, 200 ms) into the pyramidal cells. TW-001 (1-10 mg/ml) exerted a concentration-dependent reduction of the tetrodotoxin-sensitive sodium currents and high voltage-activated calcium currents. These results suggest that TW-001 is an interesting new anticonvulsant agent that exerts its anticonvulsant activity through inhibition of sodium and calcium channels, stabilizing neuronal membrane excitability and inhibiting glutamate release.

[Different age of asthmatic patients affected by different aeroallergens]

A total of 1070 cases of bronchial asthma, aged from 3 to 70 years, were analyzed for their hypersensitivity to the four most common aeroallergens, Dermatophagoides pteronyssinus, German cockroaches, Penicillium notatum and Candida albicans. The severity of hypersensitivity was classified as mild, moderate and severe based on the concentration of allergen specific IgE in the sera. Results showed that there were 77.9% patients allergic to D. pteronyssinus, 40.0% to G. cockroaches, 9.6% to P. notatum and 10.4% to C. albicans. The incidence and severity varied with age. For D. pteronyssinus, the highest incidence was 96.8% with the age between 11 and 20 years. Seventy percent of them were severe hypersensitivity. For P. notatum, the highest incidence was 18.9% with the age above 61 years. None of them were severe hypersensitivity and 11.9% of them were moderate hypersensitivity. For C. albicans, the highest incidence was 27.3% with the age between 51 and 60 years. All of them were mild hypersensitivity. For G. cockroaches, the highest incidence was 55.4% with the age between 21 and 30 years. 76.8% of them were mild hypersensitivity and 23.2% were moderate hypersensitivity. We concluded that different age of asthmatic patients affected by different aeroallergens. D. pteronyssinus was the most potent aeroallergen. Most asthmatic patients sensitized by mite were severe, particularly those patients with the age below 20 years of age.

Prior short-term synaptic disinhibition facilitates long-term potentiation and suppresses long-term depression at CA1 hippocampal synapses

Long-term potentiation (LTP) and long-term depression (LTD) are two main forms of activity-dependent synaptic plasticity that have been extensively studied as the putative mechanisms underlying learning and memory. Current studies have demonstrated that prior synaptic activity can influence the subsequent induction of LTP and LTD at Schaffer collateral-CA1 synapses. Here, we show that prior short-term synaptic disinhibition induced by type A gamma-aminobutyric acid (GABA) receptor antagonist picrotoxin exhibited a facilitation of LTP induction and an inhibition of LTD induction. This effect lasted between 10 and 30 min after washout of picrotoxin and was specifically inhibited by the L-type voltage-operated Ca2+ channel (VOCC) blocker nimodipine, but not by the N-methyl-D-aspartate (NMDA) receptor antagonist D-2-amino-5-phosphopentanoic acid (D-APV). Moreover, this picrotoxin-induced priming effect was mimicked by forskolin, an activator of cyclic adenosine monophosphate (cAMP)-dependent protein kinase (PKA), and was blocked by the adenylyl cyclase inhibitor 9-(tetrahydro-2-furanyl)-9H-purin-6-amine (SQ 22536) and the PKA inhibitor Rp-adenosine 3',5'-cyclic monophosphothioate (Rp-cAMPS). It was also found that following picrotoxin application, CA1 neurons have a higher probability of synchronous discharge in response to a population of excitatory postsynaptic potential (EPSP) of fixed slope (EPSP/spike potentiation). However, picrotoxin treatment did not significantly affect paired-pulse facilitation (PPF). These findings suggest that a brief of GABAergic disinhibition can act as a priming stimulus for the subsequent induction of LTP and LTD at Schaffer collateral-CA1 synapses. The increase in Ca2+ influx through L-type VOCCs in turn triggering a cAMP/PKA signalling pathway is a possible molecular mechanism underlying this priming effect.

HLA-DMA and HLA-DMB genotyping in patients with systemic lupus erythematosus

OBJECTIVE. To investigate the relation of HLA-DMA and DMB alleles to the development of systemic lupus erythematosus (SLE).

METHODS

We studied HLA-DMA and DMB alleles in 108 patients with SLE and 138 healthy controls using the amplification created restriction site method.

RESULTS

The phenotypic frequency of HLA-DMA*0104 was significantly higher in patients with SLE than in healthy controls. The HLA-DMA and DMB alleles were not related to clinical manifestations and various laboratory tests in patients with SLE.

CONCLUSION

HLA-DMA*0104 may be associated with the susceptibility of SLE.

Risk factors for a first febrile convulsion in children: a population study in southern Taiwan

PURPOSE

To identify risk factors for a first febrile convulsion among 3-year-old children by a matched case-control population study.

METHODS

All 11,714 neonatal survivors born in Tainan City between October 1989 and September 1991 were enrolled. At age 3, 10,460 children were available for telephone survey for febrile convulsions, and were confirmed by home visit interviews. Those without history of seizure were randomly matched to each febrile convulsion case by age, gender, and residence district.

RESULTS

Two hundred fifty six children had febrile convulsions, and 218 of them and their matched controls were available for analysis. The febrile convulsion cases had significantly more febrile episodes (four or more) per year (33.0 vs. 22.5%; p = 0.021), and cases had a higher percentage of developmental delay (3.7 vs. 0.4%; p = 0.046) and a higher percentage of febrile convulsions in their siblings (12 vs. 0.4%; p = 0.011) than controls. The other sociodemographic, environmental, and biologic variables showed no differences between cases and controls. Step-wise logistic regression showed a highly significant independent association between febrile convulsions and history of febrile convulsions in the siblings, and a moderate one between febrile convulsions and the number of febrile episodes per year.

CONCLUSIONS

The presence of febrile convulsions in the siblings and the number of fever episodes per year were the independent and significant predictors of febrile convulsion for an individual case in our population-based sample.

HLA-DMA and HLA-DMB genotyping in patients with rheumatic diseases

To investigate the correlation of HLA-DMA and DMB alleles to some rheumatic diseases, HLA-DMA and DMB genes were detected in 11 patients with juvenile rheumatoid arthritis (JRA), 22 patients with psoriatic arthritis, 26 patients with Behcet's disease, 62 patients with ankylosing spondylitis (AS), and 138 unrelated healthy controls. There was no significant difference in phenotypic frequencies of HLA-DMA and DMB alleles between controls and patients with these rheumatic diseases. HLA-DMA and DMB genes are not related to the susceptibility of JRA, psoriatic arthritis, Behcet's disease, and AS.

An indigenous melioidosis: a case report

Melioidosis is a rare but potentially fatal infectious disease in Taiwan, although it has been endemic in Southeast Asia, especially northeast Thailand, and northern Australia. In this article, we report a male diabetes with fulminant pneumonia, and septicemia caused by Burkholderia pseudomallei without traveling abroad before this episode. Productive cough and intermittent chills, high fever for one week, followed by progressively deteriorating dyspnea, shock, disturbed consciousness status were the major presentations. Blood culture grew B. pseudomallei on the fifth admission day. Unfortunately, the patient died on the 9th admission day, despite intensive care and the broad-spectrum antimicrobial regimen used.

The respiratory burst activity of activated eosinophils in atopic asthmatics

Although activated eosinophils in peribronchial tissue and peripheral blood are increased in patients with asthma, the mechanisms contributing to their presence and causing airway hyperreactivity are not well established. Recently, the respiratory burst activity on activated eosinophils can be evaluated by dual staining with monoclonal antibody EG2 and 2,7-dichlorofluorescein diacetate, which can be analyzed with the FACS analyzer. The severity of allergy and airway hyperreactivity can be evaluated by allergen-specific IgE and airway hyperresponsiveness to methacholine. In this study we evaluated the cell numbers with respiratory burst activity on activated eosinophils and correlated these cell numbers with the allergen-specific IgE and airway hyperresponsiveness to methacholine. Results showed that the cell number with respiratory burst activity of activated eosinophils was increased in those patients with more hyperresponsiveness to methacholine and correlated with PD20 of methacholine with r = -0.643 and p = 0.01. The number of activated eosinophils was also correlated with allergen-specific IgE with r = 0.641 and p = 0.025. There were increased cell numbers of activated eosinophils (EG2(+)/PMN) and cells with respiratory burst activity (DCF+EG2(+)/PMN) in the unstable asthmatic patients when compared to those of stable asthmatic patients. These results suggest that there is in vivo activation of eosinophils in the asthmatic patients, especially in the unstable patients and patients who have airways more hyperreponsive to methacholine. We concluded that the cell numbers with respiratory burst activity of activated eosinophils cannot only reflect the airway hyperresponsiveness but also the disease severity of asthmatic patients.

Salmonella choleraesuis bacteremia in southern Taiwan

Within a 6-year period from January 1991 to December 1996, 19 patients with Salmonella choleraesuis bacteremia were enrolled for clinical and microbiological analysis. Young children, the elderly and patients with hematological malignancy (36.8%), liver cirrhosis (26.3%), systemic lupus erythematosus (10.5%), chronic renal impairment (10.5%), and peptic ulcer (10.5%) were at high risk of this infection. The ratio of male to female was 3:1. Three cases (15.8%) were nosocomially acquired. Fever (89.5%), chills (57.9%) and anorexia (52.6%) were the most common clinical manifestations. Seven patients (36.8%) presented no gastrointestinal manifestations. Normal white blood cell count was noted in seven patients (36.8%), and neutropenia caused by underlying diseases or severe infection was found in six cases (31.6%). Various types of metastatic focal infections were found, such as septic arthritis, cutaneous infection, spontaneous bacterial peritonitis, and pneumonia. The severe immunocompromised status of patients and the high virulence of this pathogen may contribute to the high case fatality rate (21%). Higher resistance rate to commonly used antimicrobial agents was noted in ampicillin (94.7%), chloramphenicol (89.5%), and TMP/SMZ (63.8%). All strains of S. choleraesuis were susceptible to third-generation cephalosporins and fluoroquinolones. Generally, S. choleraesuis bacteremia should be taken into account in the differential diagnosis of sepsis in immunocompromised patients, even without gastrointestinal manifestations. The third-generation cephalosporins and fluoroquinolones may be the first choice for treatment of this invasive infections.

Epidemiological study of human salmonellosis during 1991-1996 in southern Taiwan

Within a 6-year period from January 1991 to December 1996, 249 patients of salmonellosis admitted to Kaohsiung Medical College Hospital were enrolled for clinical and microbiological analysis. The number of patients increased by year from 1991 (14 patients) to 1996 (79 patients), especially in the case of nontyphoid salmonellosis. There were 57 different serotypes isolated during these period. Salmonella typhimurium was the most common clinical serotype of human origin in southern Taiwan, followed by S. choleraesuis, S. schwanzengrund, and S. derby. Fever (81.1%), diarrhea (68.9%), and anorexia (44.6%) were the most common manifestations of human salmonellosis. Relative bradycardia was a more important feature in S. typhi group (100%) than nontyphoid salmonellosis. Leukocytosis, especially lymphocytosis, was found especially in nontyphoid, but not in typhoid salmonellosis. Elevated liver function tests were found in the most severe patients, such as S. choleraesuis and S. typhi infections. Malignancy (8.8%), especially hematological malignancy (5.2%), gastrointestinal diseases (8.8%), and diabetes mellitus (6.4%) were the common underlying diseases. Case fatality rate of human salmonellosis was 8% (20/249), especially high in S. choleraesuis group. The severity of underlying diseases may be the major cause in S. choleraesuis group. There was no fatal case with typhoid fever. Very high resistance rate to commonly used antimicrobial agents in nontyphoid Salmonella was noted in southern Taiwan with overall rates of resistance to ampicillin, 67.9%, chloramphenicol, 66.7%, and TMP/SMZ, 42.2%. The emergence of ciprofloxacin-resistant and multiresistant strains was also a major therapeutic problem in this study.

Different densities of human eosinophils respond differently to PAF and IL-5

Human eosinophils are heterogeneous, consisting of both normal and light density cells which may differ in their functional properties. In this study, we compared different densities of eosinophils in response to PAF and IL-5. The eosinophil activation markers were identified either by staining with monoclonal antibody EG2 or, by respiratory burst activity with dichrofluorescin diacetate (DCFH-DA). Both functions were analysed by flow cytometric analyzer. Results showed that light density eosinophils stained with a higher percentage of EG2 (EG2/ Kimura stain) in comparison with normal density eosinophils (88.5 +/- 19.1% vs. 43.9 +/- 18.5% p <0.01). When both groups of cells were analysed with the respiratory burst activity, on EG2+ cells, the activity in light density EG2+ cells were much higher than that of normal density EG2+ cells. These activities in both groups of cells can be further enchanced by PAF and IL-5. Furthermore, the light density EG2+ cells were more eligible to PAF and IL-5 stimulation than were normal density EG2+ cells. In conclusion, normal density and light density eosinophils had different respiratory burst activities; both groups of EG2+ eosinophils responded differently to PAF and IL-5.