Y H Ni

National Taiwan University, T’ai-pei, Taipei, Taiwan

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Publications (62)293.06 Total impact

  • Paediatric respiratory reviews 07/2013; 14:S68. DOI:10.1016/S1526-0542(13)70101-5 · 2.20 Impact Factor

  • Journal of Hepatology 03/2011; 54. DOI:10.1016/S0168-8278(11)60891-X · 11.34 Impact Factor
  • P W Chen · W L Hwu · M C Ho · N C Lee · Y H Chien · Y H Ni · P H Lee ·
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    ABSTRACT: Chen PW, Hwu WL, Ho MC, Lee NC, Chien YH, Ni YH, Lee PH. Stabilization of blood methylmalonic acid level in methylmalonic acidemia after liver transplantation. Pediatr Transplantation 2010: 14: 337–341. © 2009 John Wiley & Sons A/S. Abstract: Methylmalonic acidemia with complete mutase deficiency (mut0 type) is an inborn error of metabolism with high mortality and morbidity. LT has been suggested to be a solution to this disease, but elevation of urinary and blood MMA was still observed after LT. In this study, we measured dry blood spot MMA and its precursor propionyl-carnitine (C3-carnitine) for mut0 patients. The results revealed that when C3-carnitine rose during metabolic stress, MMA rose exponentially (up to 1000 μmol/L) in patients who did not undergo LT. In patients who underwent LT, MMA rose to 100–200 μmol/L when C3-carnitine reached 10–20 μmol/L. However, when C3-carnitine rose further to 40–50 μmol/L, MMA levels just stayed put. Therefore, LT stabilized blood MMA level, though there might be a threshold for blood MMA clearance by the donor liver. This finding should be critical to understand the long-term outcome for LT in methylmalonic acidemia.
    Pediatric Transplantation 08/2009; 14(3):337-41. DOI:10.1111/j.1399-3046.2009.01227.x · 1.44 Impact Factor
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    W. J. Su · W. Y. Cheng · D. P. Liu · Y. H. Ni · L. C. Hsu · C. Y. Lu ·

    International Journal of Infectious Diseases 12/2008; 12. DOI:10.1016/j.ijid.2008.05.213 · 1.86 Impact Factor
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    International Journal of Infectious Diseases 12/2008; 12. DOI:10.1016/j.ijid.2008.05.231 · 1.86 Impact Factor
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    C. Y. Lu · Y. H. Ni · L. Y. Chang · C. Y. Lee · D. S. Chen · L. M. Huang ·

    International Journal of Infectious Diseases 12/2008; 12. DOI:10.1016/j.ijid.2008.05.349 · 1.86 Impact Factor
  • J. H. Lee · H. L. Chen · Y.H. Ni · H.Y. Hsu · M. H. Chang ·
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    ABSTRACT: Neonatal Dubin-Johnson syndrome (DJS) is rarely diagnosed and mutational analysis of multidrag-resistance-associated protein 2 (MRP2) in such patients had not been reported. We aimed to investigate the possible correlations between genotype and phenotype of patients with DJS. Four cases of DJS, two diagnosed during the neonatal period and two diagnosed at adolescence, were followed for 5-20 y. Mutational analysis in the MRP2/ABCC2 gene was performed in all four cases. Biphasic pattern of jaundice attack was observed in one patient who was followed for 20 y, with jaundice subsiding before 1 y of age and recurring at adolescence. Six novel mutations in four patients were found, including deletions (2748del136, 3615del229, and Del3399-3400), and missense mutations (L441M and E1352Q) and nonsense mutation (Y1275X). The immunohistochemical staining in liver tissues from two patients with neonatal onset showed negative staining for MRP2. Reviewing previously reported cases, all patients diagnosed as DJS before 10 y of age have mutations involving one of the two ATP-binding cassettes (ABC) of the MRP2. This study suggests that long-term follow-up is indicated for neonatal DJS because of possible recurrence and/or second attacks of jaundice in later life, and that disruption of functionally important ABC domains in MRP2 may be related to the earlier onset of the disease.
    Journal of Hepatology 04/2006; 44(4):S242. DOI:10.1016/S0168-8278(06)80653-7 · 11.34 Impact Factor
  • PC Chan · HL Chen · MS Kong · FC Huang · HC Lee · CC Lin · CC Liu · IH Lee · TC Wu · SF Wu · YH Ni · HY Hsu · MH Chang ·
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    ABSTRACT: Aim: To investigate the factors affecting the outcome of fulminant hepatic failure (FHF) in children in relation to hepatitis B virus (HBV) infection. Methods: Retrospective review of a total of 94 cases (61 males and 33 females, aged from I month to 15 years) recruited from nine tertiary referral centers in Taiwan from 1985 to 1999. Results: The overall mortality rate was 75%. Patients in the mortality group were of an older age, had higher peak total bilirubin levels, a longer prothrombin time, and a lower percentage of HBV positivity (P < 0.001, P = 0.003, P = 0.0027 and P = 0.042, respectively). Mortality was 65% in the HBV positive (n = 42) and 83% in the HBV negative (n = 52) group (P = 0.05). In the HBV positive group, the prothrombin time was noted to be the single factor affecting outcome (P = 0.036). In the HBV negative group, older age and higher peak value of total serum bilirubin were suggestive of poor survival rate (P < 0.001 and P = 0.006, respectively). Multivariate analysis revealed that total bilirubin was the single factor affecting outcome in the HBV-negative group. The mortality rate of HBV positive children in three consecutive time periods without liver transplantation (1985-1989, 1990-1994, 1995-1999) decreased gradually (91, 67 and 38%, respectively, with P= 0.027). This change was not observed in HBV-negative cases. Conclusions: Hepatitis B virus positive FHF had a lower mortality rate than HBV negative FHF, with each group having different factors affecting mortality. (C) 2005 Blackwell Publishing Asia Pty Ltd.
    Journal of Gastroenterology and Hepatology 08/2005; 20(8):1223-1227. DOI:10.1111/j.1400-1746.2005.03923.x · 3.50 Impact Factor

  • Journal of Pediatric Gastroenterology and Nutrition 06/2004; 39(Supplement 1). DOI:10.1097/00005176-200406001-00463 · 2.63 Impact Factor
  • YH Ni · M H Chang · L M Huang · H L Chen · HY Hsu · TY Chiu · K S Tsai · D S Chen ·
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    ABSTRACT: Hepatitis B virus (HBV) infection is hyperendemic in Taiwan. Before universal HBV immunization was started in Taiwan in 1984, the carrier rate for hepatitis B surface antigen (HBsAg) was 15% to 20% in the general population. To quantify the population impact of a mass vaccination program for HBV 15 years after its implementation. Descriptive analysis of serologic markers of HBV in healthy children and adolescents. Chung-Cheng District, Taipei City, Taiwan, in 1999. 1357 persons younger than 15 years of age, who were born after the implementation of universal HBV vaccination, and 559 persons 15 to 20 years of age, who were born before the program began. Repeated serologic surveys similar to those done before and 5 and 10 years after the national vaccination program was implemented. All participants were tested for serum HBsAg, its antibody (anti-HBs), and hepatitis B core antibody (anti-HBc). During the 15 years since the vaccination program was implemented, the prevalence of HBsAg among persons younger than 15 years of age decreased from 9.8% in 1984 to 0.7% in 1999; among persons 15 to 20 years of age, the 1999 prevalence of HBsAg was 7% (P < 0.001). Hepatitis B core antibody seropositivity, which represents HBV infection, was found in 2.9% of persons younger than 15 years of age and in 20.6% of persons 15 to 20 years of age (P < 0.001); in the same age groups, the rate of anti-HBs seropositivity was 75.8% and 70.7%, respectively (P = 0.02). Universal vaccination significantly decreased the HBV carrier rate and infection rate among children and adolescents born since the program began. By decreasing the carrier pool, continuation of the national HBV immunization program should prevent HBV infection in the children of Taiwan, and, subsequently, adults as well.
    Annals of internal medicine 11/2001; 135(9):796-800. · 17.81 Impact Factor
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    HY Hsu · M H Chang · YH Ni · S F Huang ·
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    ABSTRACT: Murine extrahepatic bile duct epithelial cells (MEBEC) were isolated from extrahepatic bile ducts of BALB/c mice and established in primary culture. The epithelial origin was confirmed by positive cytokeratin 19 staining for these cells and the presence of microvilli and tight junctions under electron microscopy. By immunofluorescent staining with monoclonal antibodies and flow-cytometric analysis, MEBEC in culture constitutively express low levels of intercellular adhesion molecule (ICAM)-1, class I and class II major histocompatibility (MHC) antigens. The expression of ICAM-1 was significantly increased by interferon gamma (INF-gamma) or tumour necrosis factor alpha (TNF-alpha) stimulation. Class I and class II antigen expression were significantly enhanced by INF-gamma and in vitro murine cytomegalovirus (MCMV) infection. MEBEC infected with MCMV revealed a progressive cytopathic effect. MEBEC activated by INF-gamma or infected by MCMV induced a low but significant proliferation of allogeneic T cells and displayed a significant decrease in the absorbance at O.D. 550 nm in a microtitre tetrazolium assay after these treated cells were co-cultured with allogeneic T cells. These results suggest that following the up-regulation of surface MHC antigen and adhesion molecule expression with cytokines or MCMV, the MEBEC can function as antigen-presenting cells and initiate T-cell proliferation, which in turn trigger the recognition of MEBEC by effector T-cell-mediated cytotoxic responses. These findings may be implicated in the pathogenesis of virally induced, immune-mediated extrahepatic bile duct damage disorders.
    Clinical & Experimental Immunology 11/2001; 126(1):84-91. DOI:10.1046/j.1365-2249.2001.01558.x · 3.04 Impact Factor
  • E T Wu · H L Chen · YH Ni · P I Lee · HY Hsu · H S Lai · M H Chang ·
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    ABSTRACT: Bacterial cholangitis (BC) is a common complication in patients with biliary atresia (BA) and is characterized by fever, acholic stools and positive blood cultures. The diagnosis is often empirical because the yield of blood cultures is low. It is difficult to differentiate BC from other febrile episodes. In order to characterize the clinical and laboratory features of BC in patients with BA, identify risk factors, and correlate cholangitis with outcome, 37 patients with BA from 1993 to 1998 who underwent a Kasai operation in our hospital were studied. The follow-up period ranged from 6 to 59 months. A total of 107 febrile episodes were documented in these patients. The diagnostic criteria for cholangitis were fever, increased jaundice, or acholic stools. The clinical features, laboratory data, results of bacterial cultures, and outcomes were analyzed retrospectively. A total of 107 febrile episodes, including 78 bouts of cholangitis and 29 non-cholangitis infections, were found in 34 patients. Patients with BC had higher postoperative bilirubin levels (P = 0.02) and less frequent use of prophylactic antibiotics (P = 0.05) than those with non-cholangitis infections. Abnormal white blood cell counts (> 12,000 or <4,000 mm3) tended to be present in patients with BC (P = 0.08). There were no statistical differences in the risk factors and laboratory data between culture-positive (n = 16) and -negative (n = 62) cholangitis cases. The occurrence of cholangitis significantly reduced survival in both patients with good (P = 0.03) and inadequate bile flow (P = 0.03). All 9 patients who had never had cholangitis survived during the follow-up period. Repeated attacks of BC further decreased survival probability. The responsive organisms were mainly enteric bacteria, including Escherichia coli, Enterobacter cloacae, Klebsiella pneumoniae, Pseudomonas aeruginosa, Acinetobacter baumanni, and Salmonella typhi. The sensitivity tests justified empirical therapy with ceftriaxone. The effectiveness of prophylactic trimethoprim-sulfamethoxazole or neomycin warrants further studies. BC was a highly prevalent postoperative complication in patients with BA, especially those with inadequate bile drainage. It significantly affected early mortality. Aggressive and complete treatment with empirical ceftriaxone was appropriate.
    Pediatric Surgery International 08/2001; 17(5-6):390-5. DOI:10.1007/s003830000573 · 1.00 Impact Factor
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    H L Chen · P S Chang · H C Hsu · J H Lee · Y H Ni · H Y Hsu · Y M Jeng · M H Chang ·
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    ABSTRACT: MDR3 P-glycoprotein mediates canalicular phospholipid transport in hepatocytes. Defects in the MDR3 gene have been found to cause a subtype of progressive familial intrahepatic cholestasis (PFIC) with high gamma-glutamyltranspeptidase (GGT) levels. Affected children develop proliferation of biliary epithelium, portal inflammation, and biliary cirrhosis. The frequency of MDR3 mutations in patients with high GGT-PFIC is unclear. There have been no Asian patients reported to carry MDR3 mutations. To determine the role of MDR3 defects in chronic cholestatic patients, we studied six Taiwanese children from five families who presented high GGT-PFIC among 47 patients with infantile onset chronic intrahepatic cholestasis. Sequence analysis of MDR3 cDNA from liver tissues was performed. Only one patient had mutation in the MDR3 gene. This patient had a homozygous 719-bp deletion (nucleotide 287 to 1005) of liver cDNA encompassing exon 5 to 9 and leading to protein truncation. The onset age was 1 y in contrast with the other five patients who presented neonatal cholestasis. Four patients without mutation, including one sibling pair, exhibited histologic features of prominent portal fibrosis leading to advanced biliary cirrhosis that were indistinguishable from the case of MDR3 mutation. We concluded that mutations in MDR3 accounted for approximately 2% (1/47) of infantile onset chronic cholestasis in Taiwan. Those patients presenting high GGT-PFIC with early onset cholestasis but without MDR3 mutation probably had inheritable disorders remaining to be clarified.
    Pediatric Research 08/2001; 50(1):50-5. DOI:10.1203/00006450-200107000-00011 · 2.31 Impact Factor
  • Y J Yang · J C Yang · YM Jeng · M H Chang · YH Ni ·
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    ABSTRACT: Little is known about the prevalence of antibiotic-resistant Helicobacter pylori infection in children. Culture and antimicrobial susceptibility testing are generally time-consuming and not a routine in many hospitals. To investigate the prevalence of clarithromycin-resistant H. pylori strains in children, to identify those isolates via rapid methodology and to examine the severity of gastritis caused by the antibiotic-resistant H. pylori isolates. Enrolled were 245 children investigated for H. pylori infection by endoscopic examination. The gastric antral specimens were subjected to DNA extraction and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) with primers specific to the H. pylori 23S rRNA gene. Conventional bacterial cultures were performed simultaneously as the diagnostic standard. Minimal inhibitory concentrations of clarithromycin and metronidazole were determined by E test. This was used as a standard to determine the sensitivity and specificity of the above PCR-RFLP assay. The specimens were processed for histologic examination and evaluated by the updated Sydney system. H. pylori was isolated in 67 of the 245 children; 12 (18%) of them were clarithromycin-resistant and 6 (9%) were metronidazole-resistant. No difference in histologic examinations was noted between the antibiotic-resistant and -susceptible strains. We performed PCR-RFLP with all 12 clarithromycin-resistant isolates: 10 had a 23S ribosomal RNA A2144G point mutation; 1 had a mixture of an A2143G point mutant and susceptible strains; and 1 had neither of the 2 mutations. The prevalence of clarithromycin-resistant H. pylori isolates in Taiwanese children is 18%. PCR-RFLP had a high sensitivity (92%) and specificity (100%) for the clarithromycin resistance gene mutation determination. The dominant mutation is A2144G. PCR-RFLP provides a rapid and accurate approach to detect clarithromycin-resistant strains within 24 h.
    The Pediatric Infectious Disease Journal 08/2001; 20(7):662-6. DOI:10.1097/00006454-200107000-00005 · 2.72 Impact Factor
  • Y J Yang · M H Chang · Y H Ni ·
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    ABSTRACT: Volvulus of the sigmoid colon is rare in children. An early, accurate diagnosis can avoid unnecessary surgery and reduce the risk of complications. This condition is mainly due to a redundant sigmoid colon with a narrow mesosigmoid attachment. We describe two cases of sigmoid volvulus, which showed different clinical severities and were treated with different methods. Patient 1, a 9-year-old boy, presented with acute abdominal pain and vomiting. Patient 2, an 11-year-old boy, presented with abdominal pain, abdominal distention, and bloody mucoid stool. Plain abdominal radiographs revealed a distended colonic loop extending upward from the pelvis in patient 1 and a typical "coffee bean" sign in patient 2. Barium enema examination was used to confirm the diagnosis in both cases. The volvulus was reduced by insertion of a rectal tube in patient 1 and surgically in patient 2. Sigmoid colon volvulus should be included in the differential diagnosis of childhood abdominal pain or distention. This report suggests that nonsurgical reduction should be attempted first for uncompromised sigmoid volvulus in children, unless bowel ischemia or perforation develops.
    Journal of the Formosan Medical Association 03/2001; 100(2):134-6. · 1.97 Impact Factor
  • Lin JTH · Y H Chen · Y H Ni · H S Lai · S.S.-F. Peng ·
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    ABSTRACT: This report describes a 6-year-old girl with a choledochal cyst associated with recurrent pancreatitis. A cystic dilatation of the common bile duct was detected by abdominal ultrasound and magnetic resonance cholangiopancreatography (MRCP). She displayed only one of the classic triads: abdominal pain plus pancreatitis. Cyst excision and Roux-en-Y hepaticojejunostomy was indicated in this case. MRCP can be considered as a unique non-invasive tool and the first choice in evaluation of choledochal cyst in pediatric group.
    Acta paediatrica Taiwanica = Taiwan er ke yi xue hui za zhi 01/2001; 42(6):363-6.
  • M C Ho · R H Hu · YH Ni · H S Lai · W J Ko · M H Chang · P H Lee ·

    Transplantation Proceedings 12/2000; 32(7):2179-81. DOI:10.1016/S0041-1345(00)01624-9 · 0.98 Impact Factor
  • I J Tsai · M H Chang · H L Chen · Y H Ni · P I Lee · T Y Chiu · Assad Safary ·
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    ABSTRACT: The combination of hepatitis A virus (HAV) and hepatitis B virus (HBV) vaccinations can offer convenience, increased compliance and cost saving. We have studied the immunogenicity, reactogenicity and safety of combined hepatitis A and B vaccination in young adults (16-35 years old). Eighty healthy young adults were divided into two random groups. One group received the combined hepatitis A and B vaccine (HAB) in one arm while the other group was administered concomitant hepatitis A and B vaccines (HAV + HBV) in the right and left arms, respectively. The immunogenicity, reactogenicity and safety were assessed after each dose in both the groups. In local symptoms, the percentage of the combined HAB group was lower than the HAV + HBV group, and the general symptoms were noted in approximately 30% of each group without any significant difference. No serious adverse effects were noted. All the subjects were seropositive for antibody to hepatitis A virus (anti-HAV) after one dose of vaccine, and remained seropositive after three doses in both groups. The seropositive rate for antibody to hepatitis B surface antigen (anti-HBs) was significantly higher (84%) in the combined HAB group than the concomitant HAV + HBV group (62%), (p<0.05) after dose two, and all the subjects were seropositive (100%) after the third dose. The GMTs of anti-HAV and anti-HBs were not significantly different between groups 1 and 2 (p>0.1) except in month 6 when the GMT of anti-HBs was higher in HAB group (p=0.0039). The combined HAB vaccine was found to be safe, well tolerated and had less local symptoms in young adults. The immunogenicity and reactogenicity were similar to the concomitant HAV + HBV vaccines.
    Vaccine 11/2000; 19(4-5):437-41. DOI:10.1016/S0264-410X(00)00205-X · 3.62 Impact Factor
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    Y H Ni · M H Chang · H Y Hsu · H L Chen ·
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    ABSTRACT: Core gene deletion mutants of hepatitis B virus (HBV) have been identified in adults. Because the acquisition of HBV occurs mainly in infancy and childhood in hyperendemic areas, this study aimed to learn the temporal profile of such mutants in children with chronic HBV infection. We have followed up 365 HBV-infected children for more than 10 years and screened out HBV core gene deletion from their sera. Serial serum samples of positive cases were subjected to HBV-DNA nucleotide sequence analyses and quantification. Deletion mutants were found in 18 of the 365 patients (4.9%). Most cases (15 of 18) with deletion mutants heralded hepatitis B e antigen (HBeAg) seroconversion phase, while the other cases (3 of 18) remained in HBeAg-seropositive phase. Deletion mutants disappeared after HBeAg seroconversion except in 1 child. Decreased HBV-DNA levels accompanied deletion mutants for those who finally underwent HBeAg seroconversion, but the HBV-DNA level did not decline if there was no seroconversion. Deletion mutants were not associated with a particularly high peak liver enzyme. Core gene deletion mutants could appear as early as the age of 5. The duration of their appearance was 0.5 to 5 years. Horizontal rather than perinatal transmission of HBV was a favorable factor for these mutants to develop. Deletion fragments were located in the middle part of core gene. The emergence of the mutants was likely the result of host-viral interaction and mostly signified HBeAg seroconversion within 1 year. Core gene deletion mutants appeared preferably in children acquiring HBV by horizontal transmission.
    Hepatology 08/2000; 32(1):124-8. DOI:10.1053/jhep.2000.8529 · 11.06 Impact Factor
  • YH Ni · J T Lin · S F Huang · J C Yang · M H Chang ·
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    ABSTRACT: Invasive and noninvasive tests have been developed for the diagnosis of Helicobacter pylori infection. Because H pylori infection is acquired in childhood and adolescence, accurate diagnosis of the infection in the pediatric population is important. We conducted a study to compare invasive tests: culture, biopsy urease test, histology, and polymerase chain reaction on gastric biopsy specimens, with noninvasive tests: serology, (13)C-urea breath test, and a new diagnostic modality, stool antigen test to diagnose H pylori infection. A total of 53 children with symptoms were enrolled in this study, and all had completed the 7 diagnostic tests for H pylori. All the diagnostic tests except serology were excellent methods of diagnosing H pylori infection in children; the diagnostic accuracy was as follows: stool antigen test 96.2%, biopsy urease test 96.2%, histology 98.1%, polymerase chain reaction 94.3%, culture 98.1%, (13)C-urea breath test 100%, and serology 84.9%. The stool antigen test, being highly sensitive and specific, will be potentially very helpful in diagnosing H pylori infection in children.
    Journal of Pediatrics 07/2000; 136(6):823-7. DOI:10.1016/S0022-3476(00)00880-5 · 3.79 Impact Factor