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Y C Huang

Publications and source records attributed to Y C Huang.

At least 19 recordsLinked to original sources
PubMed2000

Expression of capsid [correction of caspid] protein VP1 for use as antigen for the diagnosis of enterovirus 71 infection.

To produce enterovirus 71 antigen for diagnostic purposes, the gene encoding the entire capsid protein VP1 was amplified by reverse transcription-polymerase chain reaction (RT-PCR), cloned and expressed in Escherichia coli as a poly-histidine fusion protein. Western blotting experiments with sera from patients with enterovirus 71 infection indicated that immunoglobulin G (IgG) and IgM antibodies bound to a single polypeptide VP1. According to these results, IgM anti-VP1 appeared in sera of patients with a symptomatic enterovirus 71 acute infection, whereas IgG anti-VP1 was present in sera of past infection. This finding suggests that detecting IgG and IgM immune responses against linear epitopes of recombinant VP1 is an effective means of determining the different phases of enterovirus 71 infection. In addition, sera containing coxsackie virus 16 (CA16) antibodies did not cross-react with the recombinant VP1 of enterovirus 71, despite the homology between VP1 proteins of both viruses. Comparison with reference PCR and neutralization assays showed these antibody tests to be appropriate for the serodiagnosis of enterovirus 71 infection.

Antibodies, Viral↗
PubMed2000

Necrotising pneumonitis in children.

UNLABELLED: We retrospectively analysed the clinical features and outcome of children under 17 years of age with necrotising pneumonitis (NP). The radiographs and CT scans of the chest of children under 17 years of age between July 1995 and March 1999 who had complicating community-acquired pneumonia were reviewed. CT scans were obtained for persistent fever, respiratory distress and sepsis despite empiric antibiotic therapy and closed tube drainage. A total of 21 children had the radiographic features of NP of whom 11 (52%) patients were successfully managed using antibiotic therapy with or without closed tube drainage. Ten patients required thoracoscopic decortications and/or lysis of pleural adhesions or debridement of empyema due to refractory pleural sepsis, failure of pulmonary re-expansion and persistent air-leaks. The most common pathogens identified were Streptococcus pneumoniae (n = 3), Staphylococcus aureus (n = 2), and Haemophilus influenzae type b (n = 2). The days of hospital stay, duration of fever and days of C-reactive protein return to normal were significantly less for the medically versus the surgically treated children (P < 0.05). CONCLUSION: The clinical course of necrotising pneumonitis in children following complicated pneumonia is often prolonged despite adequate antibiotic therapy. Necrotising pneumonitis with co-existing multiple loculations, pneumothorax/ bronchopleural fistula in the empyema and extensive pleural peel are poor prognostic factors for medical therapy. Thoracoscopic removal of loculated empyema, lysis of adhesions and/or decortication are effective in relieving tachypnoea, chest pain, and controlling fever and improve the outcome, especially in children with empyema.

Adolescent↗
PubMed2000

Transarterial embolisation of complex cavernous sinus dural arteriovenous fistulae with low-concentration cyanoacrylate.

We report the effectiveness of low-concentration n-butyl-2-cyanoacrylate (NBCA)-Lipiodol-tungsten mixture (10-15 %) in the management of patients with aggressive or recurrent complex cavernous dural arteriovenous fistulae (CSDAVF). We treated five patients with complex CSDAVF with a low concentration of an NBCA-Lipiodol-tungsten mixture after catheterisation of the feeding arteries arising from the external carotid artery. Three had a recurrent CSDAVF after transarterial particulate embolisation. Three refused transvenous treatment or could not be treated in this way; two patients had also feeding dural branches of the internal carotid artery. All patients had complete resolution of symptoms and signs within a month of the procedure. No definite neurological complication was found during follow-up ranging from 12 to 36 months. Transarterial embolisation with low-concentration cyanoacrylate appears to be an effective alternative management of aggressive or recurrent CSDAVF.

Arteriovenous Fistula↗
PubMed2000

Relationship between serotypes and genotypes based on the hypervariable region of the S1 gene of infectious bronchitis virus.

To group infectious bronchitis virus (IBV) isolates, a genetic grouping method based on hypervariable region 1 (HVR 1, nucleotides 168 to 197) was compared with that based on the whole S1 gene. Both methods resulted in the same grouping data. So the grouping method based on HVR 1 could represent the grouping method based on the whole S1 gene. Taiwan isolates could not be placed within the existing groups. In order to test the correlation between genotype and serotype, a one-way neutralization test was used to compare 9 Taiwan isolates selected from different genotypes with Massachusetts (Mass) (H120) and Connecticut (Conn) standard strains. In addition, a two-way cross-neutralization test was performed in embryonated eggs with the beta method (constant-virus, diluted-serum) and the reciprocal neutralization titers were calculated to give the relatedness (r) values. The results of two kinds of neutralizing tests showed that the serotypes of 9 isolates were different from Mass or Conn. Based on the r-values, 9 isolates were divided into two serotypes which were correlated with their genotypes. From pathogenicity tests, IBV Taiwan isolates could be divided into high, intermediate, and low pathogenicity according to their pathogenicity indexes. However, no relationship exists between pathotype and genotype. In conclusion, the genetic typing method based on HVR 1 can be used for typing IBV isolates.

Animals↗
PubMed2000

Candidaemia in special care nurseries: comparison of albicans and parapsilosis infection.

OBJECTIVES: Candidaemia caused by Candida parapsilosis (CP) is being increasingly reported among infants in neonatal intensive care units (NICU). To assess relative severity, clinical manifestations of candidaemia caused by C. albicans (CA) and CP in a NICU were compared. METHODS: Between January 1994 and July 1997, episodes of candidaemia occurring among infants hospitalized in the NICU were identified in a children's hospital. The demographic characteristics, associated risk factors, clinical manifestations and outcome of the infants with CP fungaemia were collected and compared with those of the infants with CA fungaemia. RESULTS: Twenty-four episodes caused by CA and 22 episodes caused by CP were included in this study. No significant differences were found between the two groups for gestational age, birth weight, male gender, post-natal age at onset of candidaemia, frequency of antecedent neonatal events, prior duration of antibiotic therapy and hyperalimentation, as well as presence of central venous catheter (CVC). Infants with CA fungaemia were significantly more likely than those with CP fungaemia to present with hypoxaemia, bradycardia and respiratory distress requiring intubation, and have a longer prior duration of indwelling CVC and a higher dissemination rate. The eradication rate of candidaemia and overall case fatality rate were comparable in both groups. but CP fungaemia did not appear to cause acute lethal events. CONCLUSION: The presenting signs of CP fungaemia are relatively not so severe, but CP fungaemia, which is relatively difficult to eradicate, increases the morbidity and mortality of the infants.

Blood↗
PubMed2000

Nutritional status of mechanically ventilated critically ill patients: comparison of different types of nutritional support.

Malnutrition is a common problem in hospitalized patients. Early assessment of nutritional status may help in identifying patients for whom nutritional interventions are needed. The purpose of this study was to assess and compare the nutritional status of mechanically ventilated critically ill patients who were receiving nutritional support. Forty-nine patients were divided into either enteral nutrition, total parenteral nutrition or combined (enteral plus total parenteral nutrition) groups. Anthropometric and biochemical measurements, and medical status (APACHE II score) were assessed at the 1st day and 14th day of admission in the intensive care unit (ICU) of Taichung Veteran General Hospital. The length of ventilator dependency was significantly positively correlated with calorie and carbohydrate intake in the pooled group. Patients receiving enteral and combined nutrition showed significantly lower anthropometric measurements at the 14th day after admission. Patients in all groups had abnormal mean biochemical values at the 1st day of admission. Subjects in the combined group showed a significant increase in prealbumin and the Maastricht Index levels after 14 days. Patients in all three groups were malnourished when admitted to the ICU. Patients showed a slightly improvement of nutritional status after receiving nutritional support for 14 days.

APACHE↗
PubMed2000

Fluconazole therapy in neonatal candidemia.

We reviewed 62 episodes (from 59 infants) of neonatal candidemia that occurred between January 1994 and June 1999. Except 5 term babies, all infants were premature (median gestational age [GA], 30 weeks) and birth weight was less than 2,500 g (median, 1,300 g). Most infants had reported risk factors and other neonatal problems. The age at onset of candidemia ranged from 15 to 173 days with a median of 34 days. In addition to catheter removal, all but one infants received antifungal agents and candidemia was eradicated subsequently in 46 episodes (75%). Eighteen infants with 19 episodes ever received fluconazole therapy. Fluconazole was administered as the first line agent in 6 episodes and successfully cleared candidemia in 5 episodes. Fluconazole was used as an alternative agent in an additional 13 episodes after amphotericin B (am B) +/- flucytosine were given for a period without a satisfactory result and eradication of candidemia was achieved in 8 episodes subsequently. All 18 infants tolerated fluconazole well and no withdrawal was required on account of its adverse effect. In contrast, am B alone was administered as the first line agent in 55 episodes and successfully cleared candidemia in 32 episodes (58%). This retrospective analysis suggests that fluconazole appears to be safe in neonates and can be used as an alternative agent in treating neonatal candidemia. A large-scaled prospective study may be needed.

Antifungal Agents↗
PubMed2000

Vanidipinedilol: a vanilloid-based beta-adrenoceptor blocker displaying calcium entry blocking and vasorelaxant activities.

Calcium channel and beta-adrenoceptor blockade have proved highly useful in antihypertensive therapy. Studies of the mechanisms of action of vanidipinedilol that combine these effects within a single molecule are described here. Intravenous injection of vanidipinedilol (0.1, 0.25, 0.5, 1.0, and 2.0 mg/kg) produced dose-dependent hypotensive and bradycardic responses, significantly different from nifedipine-induced (0.5 mg/kg, i.v.) hypotensive and reflex tachycardic effects in pentobarbital-anesthetized Wistar rats. A single oral administration of vanidipinedilol at doses of 10, 25, and 50 mg/kg dose-dependently reduced blood pressure with a decrease in heart rate in conscious spontaneously hypertensive rats (SHRs). In the isolated Wistar rat atrium, vanidipinedilol (10(-7), 10(-6), and 10(-5) M) competitively antagonized the (-)isoproterenol-induced positive chronotropic and inotropic effects and inhibited the increase in heart rate induced by Ca2+ (3.0-9.0 mM) in a concentration-dependent manner. The parallel shift to the right of the concentration-response curve of (-)isoproterenol and CaCl2 suggested that vanidipinedilol possessed beta-adrenoceptor-blocking and calcium entry-blocking activities. On tracheal strips of reserpinized guinea pig, cumulative doses of vanidipinedilol (10(-10) to 3x10(-6) M) produced dose-dependent relaxant responses. Preincubating the preparation with ICI 118,551 (10(-10), 10(-9), 10(-8) M), a beta2-adrenoceptor antagonist, shifted the vanidipinedilol concentration-relaxation curve significantly to a region of higher concentrations. These results implied that vanidipinedilol had a partial beta2-agonist activity. In the isolated thoracic aorta of rat, vanidipinedilol had a potent effect inhibiting high-K+-induced contractions. KCI-induced intracellular calcium changes of blood vessel smooth muscle cell (A7r5 cell lines) determined by laser cytometry also was decreased after administration of vanidipinedilol (10(-8), 10(-7), 10(-6) M). Furthermore, the binding characteristics of vanidipinedilol and various antagonists were evaluated in [3H]CGP-12177 binding to ventricle and lung and [3H]nitrendipine binding to cerebral cortex membranes in rats. The order of potency of beta1- and beta2-adrenoceptor antagonist activity against [3H]CGP-12177 binding was (-)propranolol (pKi, 8.59 for beta1 and 8.09 for beta2) > vanidipinedilol (pKi, 7.09 for beta1 and 6.64 for beta2) > atenolol (pKi, 6.58 for beta1 and 5.12 for beta2). The order of potency of calcium channel antagonist activity against [3H]nitrendipine binding was nifedipine (pKi, 9.36) > vanidipinedilol (pKi, 8.07). The ratio of beta1-adrenergic-blocking/calcium entry-blocking selectivity is 0.1 and indicated that vanidipinedilol revealed more in calcium entry-blocking than in beta-adrenergic-blocking activities. It has been suggested that vanidipinedilol-induced smooth muscle relaxation may involve decreased entry of Ca2+ and partial beta2-agonist activities. In conclusion, vanidipinedilol is a nonselective beta-adrenoceptor antagonist with calcium channel blocking and partial beta2-agonist associated vasorelaxant and tracheal relaxant activities. Particularly, the vasodilator effects of vanidipinedilol are attributed to a synergism of its calcium entry blocking and partial beta2-agonist activities in the blood vessel. A sustained bradycardic effect results from beta-adrenoceptor blocking and calcium entry blocking, which blunts the sympathetic activation-associated reflex tachycardia in the heart.

Adrenergic beta-1 Receptor Antagonists↗
PubMed2000

Factors associated with intestinal perforation in children's non-typhi Salmonella toxic megacolon.

BACKGROUND: To evaluate the risk factors for intestinal perforation in children with toxic megacolon caused by non-typhi Salmonella infection. METHODS: During an 11-year period we reviewed the records of children treated for non-typhi Salmonella infection. All of the subjects had positive stool culture for non-typhi Salmonella and were treated with intravenous ceftriaxone during hospitalization. Clinical data reviewed included demographic features, clinical manifestations, laboratory findings, radiologic findings, microbiology, therapeutic effect of hydration and rectal tube placement and the operative findings. Patients with toxic megacolon were defined as those having toxic appearance, diarrhea, high fever (>39 degrees C) and marked colon dilatation with maximal diameter > 1.5 times the width of the vertebra body of the first lumbar spine (L1-VB). To define the risk factors for patients with toxic megacolon complicated by intestinal perforation, patients were divided into two groups for analysis: P group, those complicated with intestinal perforation; and NP group, those without intestinal perforation. Differences in age, sex, severity of diarrhea, duration of fever, hemogram and its differential, culture, stool analysis, serum C-reactive protein (CRP), electrolytes, maximal colon diameter, medical therapy and timing of rectal tube insertion between the two groups were analyzed. Statistical analyses were conducted with chi square tests and multiple logistic regression. RESULTS: A total of 75 patients (P group, 27 patients; NP group, 48 patients) ages 4 months to 6 years were evaluated. With chi square analysis 7 variables were found to be significantly associated with intestinal perforation: age >1 year; fever >5 days; ratio of immature to total neutrophils >20%; serum CRP >200 mg/l; colon diameter >2.5 times the width of L1-VB; inadequate early hydration; and delay in rectal tube insertion. With multivariate analysis age >1 year, serum CRP >200 mg/l and colon diameter >2.5 times of width of L1-VB, inadequate early hydration and delay in rectal tube insertion were the most significant factors associated with intestinal perforation. CONCLUSION: Identification of patients with toxic megacolon associated with non-typhi Salmonella infection at risk for further intestinal perforation is possible. Early effective fluid resuscitation and rectal tube insertion may be helpful to prevent the occurrence of intestinal perforation.

Child↗
PubMed2000

Proinflammatory cytokines increase in sepsis after anti-adhesion molecule therapy.

Cytokine mediators and leukocyte-endothelial cell adhesion molecules are critical and interdependent components of the acute inflammatory response in sepsis. We hypothesized that the administration of monoclonal antibodies to intercellular adhesion molecule-1 (CD54) or E- and L-selectin (CD62E/L) would decrease serum levels of the proinflammatory cytokines interleukin-1beta (IL-1), IL-6, and IL-8 and tumor necrosis factor receptor (TNFR-1) in baboons during sepsis. Adult male baboons received infusions of 1 x 10(9) colony forming units (CFU)/kg heat-killed Escherichia coli (E. coli) followed 12 h later by live E. coli (1 x 10(10) CFU/kg). At the time of live bacterial infusion, six septic animals were treated with a monoclonal antibody to CD54 and six with an antibody to CD62E and L (1 mg/kg). Eight untreated septic animals served as controls. Sequentially drawn serum samples were assayed for IL-1, IL-6, IL-8, and TNFR-1 using enzyme-linked immunoassay (ELISA). Data were compared using Mann-Whitney U tests and Chi-square analyses. Median survival was decreased in both treatment groups compared to controls (P < 0.05). Peak IL-1 level was higher than controls in septic animals treated with anti-CD54 but not anti-CD62E/L (P < 0.05, P = NS, respectively). Elevations in IL-6, IL-8, and TNFR-1 were increased and prolonged in both antibody treated groups compared to controls (P < 0.05). These results provide the first in vivo evidence that leukocyte-endothelial adhesion molecules CD54 and CD62E/L regulate cytokine production in sepsis.

Animals↗
PubMed2000

Affinity cleavage at the divalent metal site of porcine NAD-specific isocitrate dehydrogenase.

A divalent metal ion, such as Mn2+, is required for the catalytic reaction and allosteric regulation of pig heart NAD-dependent isocitrate dehydrogenase. The enzyme is irreversibly inactivated and cleaved by Fe2+ in the presence of O2 and ascorbate at pH 7.0. Mn2+ prevents both inactivation and cleavage. Nucleotide ligands, such as NAD, NADPH, and ADP, neither prevent nor promote inactivation or cleavage of the enzyme by Fe2+. The NAD-specific isocitrate dehydrogenase is composed of three distinct subunits in the ratio 2alpha:1beta:1gamma. The results indicate that the oxidative inactivation and cleavage are specific and involve the 40 kDa alpha subunit of the enzyme. A pair of major peptides is generated during Fe2+ inactivation: 29.5 + 10.5 kDa, as determined by SDS-PAGE. Amino-terminal sequencing reveals that these peptides arise by cleavage of the Val262-His263 bond of the alpha subunit. No fragments are produced when enzyme is incubated with Fe2+ and ascorbate under denaturing conditions in the presence of 6 M urea, indicating that the native structure is required for the specific cleavage. These results suggest that His263 of the alpha subunit may be a ligand of the divalent metal ion needed for the reaction catalyzed by isocitrate dehydrogenase. Isocitrate enhances the inactivation of enzyme caused by Fe2+ in the presence of oxygen, but prevents the cleavage, suggesting that inactivation occurs by a different mechanism when metal ion is bound to the enzyme in the presence of isocitrate: oxidation of cysteine may be responsible for the rapid inactivation in this case. Affinity cleavage caused by Fe2+ implicates alpha as the catalytic subunit of the multisubunit porcine NAD-dependent isocitrate dehydrogenase.

Animals↗
PubMed2000

Sonographic evaluation of cellulitis in children.

Within a 3 year period from July 1996 to July 1999, a total of 105 children with clinical diagnosis of cellulitis were evaluated by ultrasonography. Eighty-six children (age range, 17 days to 15 years) fulfilling the sonographic criteria for diagnosis of cellulitis were enrolled into the study. The sonographic features were used to correlate with clinical symptoms and their duration, the peripheral leukocyte count, and the serum C-reactive protein level. Pus aspiration for immediate microscopic and later bacteriologic studies was carried out under sonographic guidance. Ultrasonographic features of cellulitis included subcutaneous tissue thickening without distortion and pus (25 cases, 29%), distortion of subcutaneous tissue without pus accumulation (26 cases, 30%), distortion of subcutaneous tissue with pus accumulation (19 cases, 23%), and distortion of tissue with abscess formation (16 cases, 18%). The presence of sonographic features of tissue distortion with or without pus accumulation, including abscess formation in children with cellulitis, correlated with a longer duration of symptoms (greater than 4 days), the presence of high-grade fever, higher peripheral leukocyte count, and higher serum C-reactive protein levels. Those patients who underwent sonographically guided aspiration or surgical intervention showed a shorter hospital stay and fever duration than those without such aspiration. Our results indicated that ultrasonography is of great value in managing cellulitis by providing information regarding the progression of inflammation. Sonographically guided aspiration of pus may be a treatment of choice, as it may decrease the need for operation.

Adolescent↗
PubMed2000

Foot complications in people with diabetes: a community-based study in Taiwan.

BACKGROUND AND PURPOSE: This comparative cross-sectional and community-based study was aimed at defining foot complications in diabetic patients. These data have not yet been reported for Asian societies. METHODS: Of a population of 3,602 subjects aged 35 years or more in Chin-Shan, Taipei, 309 diabetic patients were identified. Two hundred and nineteen (71%) of those patients were compared to 100 individuals randomly selected for the nondiabetic control group in the same community. RESULTS: Three diabetic patients underwent lower extremity amputation and four had skin ulcerations. Diabetic patients had a significantly higher prevalence of peripheral neuropathy (32.4% vs 16%), arterial insufficiency (12.6% vs 3.0%), and medial arterial calcification (13.6% vs 5.0%), when compared to the nondiabetic controls. The age and sex-adjusted rates of hallux valgus, loss of skin hair on the dorsum of the foot, tinea unguium, arterial insufficiency, medial artery calcification, and peripheral neuropathy were significantly higher in diabetic than nondiabetic subjects. Aging and hyperglycemia (> 140 mg/dL) increased the prevalence of foot complications in both groups. Foot complications were also remarkably associated with the duration of diabetes (p = 0.003). CONCLUSIONS: This study shows that diabetes mellitus is associated with an increased likelihood of foot complications in this geographically defined Taiwanese population. Patient age and diabetic duration are associated with the significantly higher prevalence of foot complications.

Adult↗
PubMed2000

The interference of uptake of thallium-201 in cultured rat myocardial cells with existence of potassium related pharmaceuticals--a preliminary report.

Thallium-201 myocardial perfusion imaging is wildly used to detect and assess the extent of jeopardized myocardial ischemia in the coronary artery disease and the viability of myocardium post infarction. In recent years, there has been a great deal of pharmacological development of blockers and openers of potassium channel. In this study, we will discuss the interference of uptake of thallium-201 ion in cultured neonatal rat myocytes with existence of a variety of pharmacological agents. The cultures of neonatal rat myocardial cells were incubated with different agents such as potassium chloride, sodium-potassium ATPase pump inhibitor (ouabain), cesium compound, variable potassium channel blockers (4 AP, TEA and glibenclamide) and their openers (minoxidil, and cromakalim). The radioactivity of intracellular thallium-201 that could enter rat myocardial cells was detected by gamma counter sixty minutes after thallium-201 was added. In this study we found that thallium and potassium ions behave in an analogous manner in cultured rat myocardial cells. Both 2.5 mM and 5 mM concentration of extracellular potassium ion significantly result in reduction of thallium-201 ion influx in rat myocardial cells. 0.5 mM ouabain, an inhibitor of sodium-potassium ATPase pump, reduced about 40% of influx of thallium-201 ion in cultured rat myocardial cells via active transport. Combination of both potassium ion and ouabain inhibit most of thallium-201 ions influx in myocardial cells, but it is not completely inhibited. Cesium, a potassium antagonist, also interferes with the uptake of thallium-201 in cultured rat myocytes in our study. The most interesting finding in our investigation is that potassium channel blockers such as TEA and glibenclamide, inhibit the influx of thallium-201 in myocytes. However, potassium channel openers have no overt effect on influx of thallium-201 in cultured rat myocytes. We indirectly observe about 60% of influx of thallium-201 ion into cultured rat myocardial cells via active sodium-potassium ATPase pump. Potassium, cesium and potassium channel blockers, such as TEA and glibenclamide, inhibited the different percentage of influx of thallium-201 in cultured rat myocardial cells in this study.

Adenosine Triphosphate↗
PubMed2000

Influenza A virus infection in infants.

Influenza A virus causes a variety of respiratory and nonrespiratory illness in children. The symptomatology varies with different age groups. The purpose of this retrospective study was to define the clinical characteristics of influenza A infection in Taiwanese infants. During the period from December 1997 to February 1998, 37 febrile patients younger than 1 year of age, including five newborns, were admitted to our hospital due to suspicion of sepsis or meningitis. The medical records of these patients were retrospectively evaluated. Influenza A virus was isolated from the specimens of the throat swabs in all patients, whereas no bacterial pathogen was detected. The most common clinical manifestations of these infants were lower respiratory tract infections, including pneumonia, bronchiolitis, and croup. There was no significant difference between the clinical characteristics of infants younger than 3 months and those aged from 3 months to 1 year. The mean duration of fever, peak of body temperature, and duration of hospitalization were 3.41 (+/-1.86) versus 4.4 (+/-2.02) days, 39.0 (+/-0.57) versus 39.9 (+/-0.63) oC, 4.9(+/-1.49) versus 6.3 (+/-3.7) days in infants younger than 3 months and infants aged from 3 months to 1 year, respectively. The older infants aged from 3 months to 1 year had a significantly higher peak body temperature than the infants younger than 3 months (p < 0.05). Two patients with croup had a more severe clinical course, however, the outcomes were good in all patients. During an influenza A virus outbreak, influenza A infection should be included in the differential diagnosis of infants with lower respiratory tract infection.

Age Factors↗