A trophoblast-likecell line, II., was established from a normal-term humanplacenta.The TI, cells ... more A trophoblast-likecell line, II., was established from a normal-term humanplacenta.The TI, cells were epithelial in morphologywith rela tively large vesicularnuclei, prominentnucleoli, and numerousmicrovilli on the cell surface. Cytoplasmic organelles were generally sparse but mitochondriaand polysomes were abundant.The cells grew as compact sheets with close membraneapproximationinterconnectedoccasionally bydesmosome-likejunctions.TL cells containedplacenta!alkaline phos- phatase, a placenta-associatedantigen, cytokeratin, and prekeratin,but not keratin.In parallel, they were
Purpose: To investigate sequence variants in the optineurin (OPTN) gene in patients with juvenile... more Purpose: To investigate sequence variants in the optineurin (OPTN) gene in patients with juvenile-onset open-angle glaucoma (JOAG) in Taiwan. Methods: We analyzed the sequence variants of OPTN in 51 unrelated Taiwanese probands with JOAG and in 51 control group subjects who did not have JOAG. Genomic DNA was extracted from the individuals and subjected to polymerase chain reaction (PCR) to
Lenticulostriate vasculopathy is associated with various disorders, in particular cytomegalovirus... more Lenticulostriate vasculopathy is associated with various disorders, in particular cytomegalovirus infection, which can cause neurological consequences. We wanted to evaluate the association of lenticulostriate vasculopathy and cytomegalovirus infection. We retrospectively collected data on lenticulostriate vasculopathy from 858 neonatal ultrasonography scans. Fifty-five patients with lenticulostriate vasculopathy were diagnosed. Lenticulostriate vasculopathy was classified as severe and mild according to the ultrasonographic findings. We analyzed gender, unilateral and bilateral lenticulostriate vasculopathy, mild and severe lenticulostriate vasculopathy, intrauterine growth retardation, and lenticulostriate vasculopathy associated with other brain malformations to determine whether they were correlated with cytomegalovirus infection. Neonatal cytomegalovirus infections correlated primarily with lenticulostriate vasculopathy that was associated with brain structure anomalies p < 0.0001, followed by severe lenticulostriate vasculopathy (p = 0.029). Cytomegalovirus urine polymerase chain reaction ratios were 69% for severe and 23% for mild lenticulostriate vasculopathy (p = 0.002; odds ratio = 7.33). Of 72 newborns with intrauterine growth retardation without lenticulostriate vasculopathy, 33 were analyzed for cytomegalovirus, of whom only one was positive, which was significantly different from the newborns with lenticulostriate vasculopathy (p = 0.003; odds ratio = 11.64). Lenticulostriate vasculopathy on neonatal ultrasonography is useful for predicting cytomegalovirus infection, particularly in severe lenticulostriate vasculopathy. When severe lenticulostriate vasculopathy is associated with a brain structure anomaly, cytomegalovirus infection should be considered. The outcomes for the cases in which cytomegalovirus infection was associated with other brain structure anomalies were significantly worse than the outcomes in cases associated with lenticulostriate vasculopathy only.
International journal of pediatric otorhinolaryngology, 2010
To determine whether variants of the TMIE gene are causes of nonsyndromic deafness in Taiwan. A g... more To determine whether variants of the TMIE gene are causes of nonsyndromic deafness in Taiwan. A genetic survey was made from 370 individuals, with 250 nonsyndromic hearing loss and 120 normal hearing individuals. Genomic DNA was extracted from peripheral blood leukocytes and then subjected to PCR to amplify selected exons and flanking introns of the TMIE gene; the amplified products were screened for base variants by autosequence. Data from the two groups were then compared using Fisher's two-tailed exact test and Armitage's trend test. The analysis revealed 7 novel variants in the TMIE gene. Of the 7 variants, 5 variants were found in both nonsyndromic hearing loss and normal hearing group. Both allelic and genotype frequencies of these sequence changes did not differ significantly between patients and controls (P>0.05). However, a missense variant (c.257G>A) and one promoter variant (g.1-219A>T) were found in two patients with nonsyndromic hearing loss. Family stu...
International journal of pediatric otorhinolaryngology, 2009
To determine whether variants of exons 7, 11, 22 and 28 of the MYO7A gene are causes of nonsyndro... more To determine whether variants of exons 7, 11, 22 and 28 of the MYO7A gene are causes of nonsyndromic deafness in Taiwanese. We screened a total of 331 unrelated Taiwanese individuals (age range, 4-22 years), including 231 patients with severe to profound nonsyndromic hearing loss and 100 individuals with normal hearing. Genomic DNA was extracted from peripheral blood leukocytes and then subjected to PCR to amplify selected exons and flanking introns of the MYO7A gene; the amplified products were screened for base mutations by autosequence. Data from the two groups were then compared using the chi-square (chi(2)) test. The analysis revealed six variants in 3 out of 4 screened exons and flanking intronic sequences of the MYO7A gene (exons 7, 11, and 22). Three missense variants were found only in patients with hearing loss and were heterozygous, including Arg206Cys, Arg206His and Thr381Met. A variant, c.IVS22+58G>A, was found in intron 22 of the MYO7A gene from both patients and co...
The effect of L-arginine on the slow motility of mammalian cochlear outer hair cells was studied ... more The effect of L-arginine on the slow motility of mammalian cochlear outer hair cells was studied in this experiment. L-Arginine (3 mM) but not D-arginine (3 mM) or other amino acids (L-aspartate or L-glutamate) induced length increases of guinea pig outer hair cell. Similarly, the membrane-permeant cGMP analogues, 8-(4-chlorophenylthio)guanosine 3P:5P-cyclic monophosphate (1 mM) or 8-bromo-guanosine 3P:5P-cyclic monophosphate (1 mM) induced length increases of guinea pig outer hair cells. These length increases induced by L-arginine can be attenuated by a 30 min preincubation of the cells with the nitric oxide synthase inhibitors N G -nitro-L-arginine methyl ester hydrochloride (3 mM) or 7-nitroindazole (1 mM). Comparing the effects of L-arginine and ionomycin on cell length and intracellular calcium change in outer hair cells, both L-arginine and ionomycin were able to induce the elongation of outer hair cells but L-arginine did not change the fluorescence intensity of Fluo-3. Preincubation of the cells with EGTA (3 mM) for 40 min to reduce the extracellular calcium concentration did not influence the effect of L-arginine. This experiment demonstrated that nitric oxide/cGMP pathway involvement in regulating the slow motility of mammalian outer hair cells cannot be ruled out. The effect of L-arginine is independent of extracellular calcium concentration. ß
2006 8th International Conference Advanced Communication Technology, 2006
The two-dimensional (2D) gel electrophoresis technique is used by biologists to separate complex ... more The two-dimensional (2D) gel electrophoresis technique is used by biologists to separate complex protein mixtures. The digitized format of the 2D gel stored in a database offers the biologist a wider range of analytical research opportunities to find the key affecting the human health. However, the 2D gel image access on the Internet can be slowed by the network's bandwidth
2005 International Conference on Neural Networks and Brain, 2005
Classification of yeast genes based on their expression levels obtained from micro array hybridiz... more Classification of yeast genes based on their expression levels obtained from micro array hybridization experiments is an important and challenging application domain in data mining and knowledge discovery. Over the past decade, neural networks and support vector machines (SVMs) have achieved good results for genes classification. This paper presents a methodology which uses two neural networks to classify unseen genes based on their expression levels. In order to remove some of the noise and deal with the imbalanced class distribution of the dataset, data pre-processing is firstly performed before data classification in which data cleaning, data transformation and data over-sampling using SMOTE algorithm are undertaken. Thereafter, two neural networks with different architectures are trained using Scaled Conjugate Gradient in two different ways: 1) the training-validation-testing approach and 2) 10-fold crossvalidation. Experimental results show that this methodology outperforms the previous best-performing SVM for this problem and 8 other classifiers: 3 SVMs, C4.5, Bayesian network, Naive Bayes, K-NN and JRip.
The major capsid protein of human polyomavirus JC virus, VP1, has been cloned into a baculovirus ... more The major capsid protein of human polyomavirus JC virus, VP1, has been cloned into a baculovirus genome and expressed in insect cells. The VP1 protein was expressed in the cytoplasm and trans- ported into the nucleus. It was then purified by a sucrose cushion and CsCl density gradient centri- fugation to near homogeneity. Electron microscopy showed that isolated recombinant VP1
A number of repetitive DNA clones were generated from PCR ampli¢cations of Indian muntjac genomic... more A number of repetitive DNA clones were generated from PCR ampli¢cations of Indian muntjac genomic DNA using primer sequences derived from a white tailed deer satellite II DNA sequence. One clone (Mmv-0.7) was characterized and shown to be a cervid satellite II DNA clone. Multiple colored FISH studies with cervid satellite I (C5) and this satellite II clone (Mmv-0.7) to Chinese muntjac metaphase chromosomes localized both satellite DNAs at the pericentromeric regions of all chromosomes except for chromosome 3 and the Y chromosome, whereas chromosome 3 exhibited pericentromeric satellite II DNA only. Where distinguishable, the pericentromeric satellite II signals appeared terminally oriented with respect to satellite I. Six pairs of Chinese muntjac autosomes had interstitial satellite I sites with four of these autosomal pairs (chromosomes 1, 2 and two other smaller autosomal pairs) also exhibiting interstitial satellite II signals. An interstitial site on the X chromosome was found to have satellite II signals. For the Indian muntjac chromosomes, FISH studies revealed a pericentromeric hybridization for satellites I and II as well as 27 distinct interstitial hybridization sites, each having at least one of the satellite DNAs. These data were used to more precisely de¢ne the chromosome fusion-associated breakpoints that presumably led to the formation of the present-day Indian muntjac karyotype. It further hints at the possibility that the Indian muntjac karyotype may have evolved directly from a 2n 70 ancestral karyotype rather than from an intermediate 2n 46 Chinese muntjac-like karyotype.
Myotonic dystrophy (DM) is an inherited, autosomal dominant muscular disease which is primarily c... more Myotonic dystrophy (DM) is an inherited, autosomal dominant muscular disease which is primarily caused by a CTG trinucleotide expansion mutation on chromosome 19ql3.3. The size of this trinucleotide repeat is related both to the age of onset and to the severity of the clinical manifestation. This disease is very rare in Taiwan, and clinical and genetic study on DM has
Mycotoxins are fungal secondary metabolites with very diversified toxic effects in humans and ani... more Mycotoxins are fungal secondary metabolites with very diversified toxic effects in humans and animals. In the present study, patulin (PAT) and citrinin (CTN), two prevalent mycotoxins, were evaluated for their genotoxic effects and oxidative damage to mammalian cells, including Chinese hamster ovary cells (CHO-K1), human peripheral blood lymphocytes, and human embryonic kidney cells (HEK293). PAT, but not CTN, caused a significant dose-dependent increase in sister chromatid exchange (SCE) frequency in both CHO-K1 and human lymphocytes. PAT also elevated the levels of DNA gap and break in treated CHO-K1. In the single cell gel electrophoresis (SCGE) assay, exposure of HEK293 to concentrations above 15 microM of PAT induced DNA strand breaks; the tail moment values also greatly increased after posttreatment with formamidopyrimidine-DNA glycosylase (Fpg). This suggests that in human cells PAT is a potent clastogen with the ability to cause oxidative damage to DNA. However, no significant change in the tail moment values in CTN-treated cultures was found, suggesting that CTN is not genotoxic to HEK293. Incubation of HEK293 with CTN increased the mRNA level of heat shock protein 70 (HSP70), but not that of human 8-hydroxyguanine DNA glycosylase 1 (hOGG1). PAT treatment did not modulate the expression of either HSP70 or hOGG1 mRNA.
Dysfunctional gap junctions caused by GJB2 (CX26) and GJB6 (CX30) mutations are implicated in nea... more Dysfunctional gap junctions caused by GJB2 (CX26) and GJB6 (CX30) mutations are implicated in nearly half of nonsyndromic hearing loss cases. A recent study identified a heterozygous mutation, c.119C.T (p.A40V), in the GJB6 gene of patients with nonsyndromic hearing loss. However, the functional role of the mutation in hearing loss remains unclear. In this study, analyses of cell biology indicated that a p.A40V missense mutation of CX30 causes CX30 protein accumulation in the Golgi body rather than in the cytoplasmic membrane. The tet-on protein expression system was used for further study of mutant proteins in CX30 and CX30A40V co-expressions and in CX26 and CX30A40V co-expressions. The p.A40V missense mutation exerted a dominant negative effect on both normal CX30 and CX26, which impaired gap junction formation. Moreover, computer-assisted modeling suggested that this p.A40V mutation affects the intra molecular interaction in the hydrophobic core of Trp44, which significantly alters the efficiency of gap junction formation. These findings suggest that the p.A40V mutation in CX30 causes autosomal-dominant nonsyndromic hearing loss. These data provide a novel molecular explanation for the role of GJB6 in hearing loss.
Mutation Research/Reviews in Mutation Research, 1997
A total of 15 newly-developed Bowen's disease patients and 34 age-sex-residence-matched controls ... more A total of 15 newly-developed Bowen's disease patients and 34 age-sex-residence-matched controls were recruited from three arseniasis-hyperendemic villages in Taiwan to compare spontaneous and arsenic-induced sister chromatid exchanges (SCEs), proportion of cells with high frequencies of SCEs (HFCS), and replication index (RI) in their peripheral lymphocytes. Arsenic-induced Bowen's disease patients were found to have significantly higher spontaneous SCEs and HFCs and a lower spontaneous RI than in matched controls without or with adjustment for age, gender, cigarette smoking, alcohol drinking, tea drinking, status of major diseases, HBsAg carrier status and arsenic exposure indices through multivariate analysis. Sodium arsenite was found to increase SCEs and HFCs and to decrease RI in a dose-response pattern for both cases and controls. The arsenic-induced decrease in RI was significantly greater in arsenic-induced Bowen's disease patients than in matched controls. The arsenic-induced increases in SCEs and HFCs were also consistently, but not statistically significantly.
Spinocerebellar ataxia (SCA) type 7 is an autosomal dominant disorder characterized by neural los... more Spinocerebellar ataxia (SCA) type 7 is an autosomal dominant disorder characterized by neural loss, mainly in the cerebellum and regions of the brainstem and particularly the inferior olivary complex. This neurodegeneration disease is associated with expansion of unstable CAG repeats within the 5'-translated region of the SCA7 gene, located on chromosome 3p. We conducted a local survey of the normal population and candidate patients for the analysis of the CAG repeats in the SCA7 gene. The distributions of the CAG repeat units of SCA7 gene in the normal population in Taiwan were established in this study by using the radioactive genomic polymerase chain reaction (PCR). The normal range of CAG repeats is from 6 to 17 repeats, with the more common being around 8-13 repeats. The range is narrower than that reported for other ethnic groups (7-35 CAGs). Meanwhile, by the use of a combination of PCR and Southern blot analysis, one SCA7 family was identified and is reported here. A marked instability of the CAG repeat number during transmission from father to son (41 vs. 100) was observed in the SCA7 family. Clinical anticipation is significant in this family including an infantile case, who was found to have nystagmus from the age of 1 month. To date, the SCA7 mutation has been detected in one of 73 families with autosomal dominant cerebellar ataxia phenotypes, which is about 1.4% of the ataxia families referred to us, compared to 1.4% SCA1, 9.6% SCA2, and 27.3% SCA3/Machado-Joseph disease in our collection. In addition, we demonstrate that the PCR-based Southern blot analysis, with the advantages of sensitivity of PCR and specificity of Southern blot, is a reliable diagnostic method for SCA7 mutation screening. The molecular analysis technique makes possible the quick and accurate diagnosis of SCA7 patients and in the future will hopefully be applied to prenatal screening for SCA7 families.
To investigate the prevalence of human polyomaviruses in Taiwan, urine samples from immunocompete... more To investigate the prevalence of human polyomaviruses in Taiwan, urine samples from immunocompetent (healthy), transient immunocompromised (pregnant), and prolonged immunosuppressed (autoimmune disease) individuals were collected throughout the island. The viral DNA in the urine was detected by the polymerase chain reaction (PCR) and Southern blot. The viral genotypes were determined by DNA sequencing within the regulatory region. The overall results, including cases reported previously, show that 13.3% (10/75) of immunocompetent individuals, 26.0% (20/77) of pregnant women, and 37.5% (18/48) of autoimmune disease patients are JCV positive. All of the immunocompetent individuals are BKV negative, but 3.9% (3/77) of the pregnant women and 6.2% (3/48) of autoimmune disease patients are BKV positive. Twenty-four percent (48/200) of the examined urine samples were JCV positive, but only 3% (6/200) were BKV positive. JCV positive individuals were mainly infected with CY (42%) and TW-1 (52%) subtypes. These results suggest that the incidence of urinary excretion of human polyomaviruses in immunosuppressed individuals is higher than that of immunocompetent individuals. The prevalence of JCV appears to be higher than that of BKV in Taiwan. In addition, CY and TW-1 are the predominant subtypes of JCV prevalent in the Taiwanese population.
Governmental officials as well as medical scientists in Taiwan have worked hard in recent years t... more Governmental officials as well as medical scientists in Taiwan have worked hard in recent years to develop and to implement various measures, such as prenatal diagnosis and neonatal screening, to lower the incidence of hereditary diseases and mental retardation in the population. An inquiry into the possibility of devising a chromosomal and biochemical screening program and to apply it routinely to all the mentally retarded school children island-wide was the major aim of the present study. A collection of 1,614 blood samples was screened for phenylketonuria (PKU), galactosemia, homocystinuria, biotinidase deficiency, and congenital hypothyroidism. The IQ of these children ranged from 50-75 (1,397 children, moderate group) to less than 50 (217 children, severe group). Six cases of PKU (one tetrahydrobiopterin deficient and five classical) and three cases of thyroid dysfunction were found. The overall incidence of these two diseases was 0.56~. Of the 1,614 blood samples, 1,323 were cultured and karyotyped successfully. One hundred and twenty-five of them had chromosome abnormalities. The majority (64 out of 125) were trisomy 21. A remarkable difference in the percentage of mentally retarded children with chromosome abnormalities was observed between the moderate (7.87~) and severe (17.51~) retardates.
Hirschsprung disease (HSCR), or congenital intestinal aganglionosis, is a relatively common disor... more Hirschsprung disease (HSCR), or congenital intestinal aganglionosis, is a relatively common disorder characterized by the absence of ganglion cells in the nerve plexuses of the lower digestive tract, resulting in intestinal obstruction in neonates. Mutations in genes of the RET receptor tyrosine kinase and endothelin receptor B (EDNRB) signaling pathways have been shown to be associated in HSCR patients. In this study, we collected genomic DNA samples from 55 HSCR patients in central Taiwan and analyzed the coding regions of the RET and EDNRB genes by PCR amplification and DNA sequencing. In the 55 patients, an A to G transition was detected in two (identical twin brothers). The mutation was at the end of RET exon 19 at codon 1062 (Y1062C), a reported critical site for the signaling pathways. Single nucleotide polymorphisms (SNP) in exons 2, 7, 11, 13, and 15 of RET and exon 4 of EDNRB in the HSCR patients or controls were detected. The differences between patients and controls in allele distribution of the five RET polymorphic sites were statistically significant. The most frequent genotype encompassing exons 2 and 13 SNPs (the polymorphic sites with the highest percentage of heterozygotes) was AA/GG in patients, which was different from the AG/ GT in the normal controls. Transmission disequilibrium was observed in exons 2, 7, and 13, indicating nonrandom association of the susceptibility alleles with the disease in the patients. This study represents the first comprehensive genetic analysis of HSCR disease in Taiwan.
A trophoblast-likecell line, II., was established from a normal-term humanplacenta.The TI, cells ... more A trophoblast-likecell line, II., was established from a normal-term humanplacenta.The TI, cells were epithelial in morphologywith rela tively large vesicularnuclei, prominentnucleoli, and numerousmicrovilli on the cell surface. Cytoplasmic organelles were generally sparse but mitochondriaand polysomes were abundant.The cells grew as compact sheets with close membraneapproximationinterconnectedoccasionally bydesmosome-likejunctions.TL cells containedplacenta!alkaline phos- phatase, a placenta-associatedantigen, cytokeratin, and prekeratin,but not keratin.In parallel, they were
Purpose: To investigate sequence variants in the optineurin (OPTN) gene in patients with juvenile... more Purpose: To investigate sequence variants in the optineurin (OPTN) gene in patients with juvenile-onset open-angle glaucoma (JOAG) in Taiwan. Methods: We analyzed the sequence variants of OPTN in 51 unrelated Taiwanese probands with JOAG and in 51 control group subjects who did not have JOAG. Genomic DNA was extracted from the individuals and subjected to polymerase chain reaction (PCR) to
Lenticulostriate vasculopathy is associated with various disorders, in particular cytomegalovirus... more Lenticulostriate vasculopathy is associated with various disorders, in particular cytomegalovirus infection, which can cause neurological consequences. We wanted to evaluate the association of lenticulostriate vasculopathy and cytomegalovirus infection. We retrospectively collected data on lenticulostriate vasculopathy from 858 neonatal ultrasonography scans. Fifty-five patients with lenticulostriate vasculopathy were diagnosed. Lenticulostriate vasculopathy was classified as severe and mild according to the ultrasonographic findings. We analyzed gender, unilateral and bilateral lenticulostriate vasculopathy, mild and severe lenticulostriate vasculopathy, intrauterine growth retardation, and lenticulostriate vasculopathy associated with other brain malformations to determine whether they were correlated with cytomegalovirus infection. Neonatal cytomegalovirus infections correlated primarily with lenticulostriate vasculopathy that was associated with brain structure anomalies p < 0.0001, followed by severe lenticulostriate vasculopathy (p = 0.029). Cytomegalovirus urine polymerase chain reaction ratios were 69% for severe and 23% for mild lenticulostriate vasculopathy (p = 0.002; odds ratio = 7.33). Of 72 newborns with intrauterine growth retardation without lenticulostriate vasculopathy, 33 were analyzed for cytomegalovirus, of whom only one was positive, which was significantly different from the newborns with lenticulostriate vasculopathy (p = 0.003; odds ratio = 11.64). Lenticulostriate vasculopathy on neonatal ultrasonography is useful for predicting cytomegalovirus infection, particularly in severe lenticulostriate vasculopathy. When severe lenticulostriate vasculopathy is associated with a brain structure anomaly, cytomegalovirus infection should be considered. The outcomes for the cases in which cytomegalovirus infection was associated with other brain structure anomalies were significantly worse than the outcomes in cases associated with lenticulostriate vasculopathy only.
International journal of pediatric otorhinolaryngology, 2010
To determine whether variants of the TMIE gene are causes of nonsyndromic deafness in Taiwan. A g... more To determine whether variants of the TMIE gene are causes of nonsyndromic deafness in Taiwan. A genetic survey was made from 370 individuals, with 250 nonsyndromic hearing loss and 120 normal hearing individuals. Genomic DNA was extracted from peripheral blood leukocytes and then subjected to PCR to amplify selected exons and flanking introns of the TMIE gene; the amplified products were screened for base variants by autosequence. Data from the two groups were then compared using Fisher's two-tailed exact test and Armitage's trend test. The analysis revealed 7 novel variants in the TMIE gene. Of the 7 variants, 5 variants were found in both nonsyndromic hearing loss and normal hearing group. Both allelic and genotype frequencies of these sequence changes did not differ significantly between patients and controls (P>0.05). However, a missense variant (c.257G>A) and one promoter variant (g.1-219A>T) were found in two patients with nonsyndromic hearing loss. Family stu...
International journal of pediatric otorhinolaryngology, 2009
To determine whether variants of exons 7, 11, 22 and 28 of the MYO7A gene are causes of nonsyndro... more To determine whether variants of exons 7, 11, 22 and 28 of the MYO7A gene are causes of nonsyndromic deafness in Taiwanese. We screened a total of 331 unrelated Taiwanese individuals (age range, 4-22 years), including 231 patients with severe to profound nonsyndromic hearing loss and 100 individuals with normal hearing. Genomic DNA was extracted from peripheral blood leukocytes and then subjected to PCR to amplify selected exons and flanking introns of the MYO7A gene; the amplified products were screened for base mutations by autosequence. Data from the two groups were then compared using the chi-square (chi(2)) test. The analysis revealed six variants in 3 out of 4 screened exons and flanking intronic sequences of the MYO7A gene (exons 7, 11, and 22). Three missense variants were found only in patients with hearing loss and were heterozygous, including Arg206Cys, Arg206His and Thr381Met. A variant, c.IVS22+58G>A, was found in intron 22 of the MYO7A gene from both patients and co...
The effect of L-arginine on the slow motility of mammalian cochlear outer hair cells was studied ... more The effect of L-arginine on the slow motility of mammalian cochlear outer hair cells was studied in this experiment. L-Arginine (3 mM) but not D-arginine (3 mM) or other amino acids (L-aspartate or L-glutamate) induced length increases of guinea pig outer hair cell. Similarly, the membrane-permeant cGMP analogues, 8-(4-chlorophenylthio)guanosine 3P:5P-cyclic monophosphate (1 mM) or 8-bromo-guanosine 3P:5P-cyclic monophosphate (1 mM) induced length increases of guinea pig outer hair cells. These length increases induced by L-arginine can be attenuated by a 30 min preincubation of the cells with the nitric oxide synthase inhibitors N G -nitro-L-arginine methyl ester hydrochloride (3 mM) or 7-nitroindazole (1 mM). Comparing the effects of L-arginine and ionomycin on cell length and intracellular calcium change in outer hair cells, both L-arginine and ionomycin were able to induce the elongation of outer hair cells but L-arginine did not change the fluorescence intensity of Fluo-3. Preincubation of the cells with EGTA (3 mM) for 40 min to reduce the extracellular calcium concentration did not influence the effect of L-arginine. This experiment demonstrated that nitric oxide/cGMP pathway involvement in regulating the slow motility of mammalian outer hair cells cannot be ruled out. The effect of L-arginine is independent of extracellular calcium concentration. ß
2006 8th International Conference Advanced Communication Technology, 2006
The two-dimensional (2D) gel electrophoresis technique is used by biologists to separate complex ... more The two-dimensional (2D) gel electrophoresis technique is used by biologists to separate complex protein mixtures. The digitized format of the 2D gel stored in a database offers the biologist a wider range of analytical research opportunities to find the key affecting the human health. However, the 2D gel image access on the Internet can be slowed by the network's bandwidth
2005 International Conference on Neural Networks and Brain, 2005
Classification of yeast genes based on their expression levels obtained from micro array hybridiz... more Classification of yeast genes based on their expression levels obtained from micro array hybridization experiments is an important and challenging application domain in data mining and knowledge discovery. Over the past decade, neural networks and support vector machines (SVMs) have achieved good results for genes classification. This paper presents a methodology which uses two neural networks to classify unseen genes based on their expression levels. In order to remove some of the noise and deal with the imbalanced class distribution of the dataset, data pre-processing is firstly performed before data classification in which data cleaning, data transformation and data over-sampling using SMOTE algorithm are undertaken. Thereafter, two neural networks with different architectures are trained using Scaled Conjugate Gradient in two different ways: 1) the training-validation-testing approach and 2) 10-fold crossvalidation. Experimental results show that this methodology outperforms the previous best-performing SVM for this problem and 8 other classifiers: 3 SVMs, C4.5, Bayesian network, Naive Bayes, K-NN and JRip.
The major capsid protein of human polyomavirus JC virus, VP1, has been cloned into a baculovirus ... more The major capsid protein of human polyomavirus JC virus, VP1, has been cloned into a baculovirus genome and expressed in insect cells. The VP1 protein was expressed in the cytoplasm and trans- ported into the nucleus. It was then purified by a sucrose cushion and CsCl density gradient centri- fugation to near homogeneity. Electron microscopy showed that isolated recombinant VP1
A number of repetitive DNA clones were generated from PCR ampli¢cations of Indian muntjac genomic... more A number of repetitive DNA clones were generated from PCR ampli¢cations of Indian muntjac genomic DNA using primer sequences derived from a white tailed deer satellite II DNA sequence. One clone (Mmv-0.7) was characterized and shown to be a cervid satellite II DNA clone. Multiple colored FISH studies with cervid satellite I (C5) and this satellite II clone (Mmv-0.7) to Chinese muntjac metaphase chromosomes localized both satellite DNAs at the pericentromeric regions of all chromosomes except for chromosome 3 and the Y chromosome, whereas chromosome 3 exhibited pericentromeric satellite II DNA only. Where distinguishable, the pericentromeric satellite II signals appeared terminally oriented with respect to satellite I. Six pairs of Chinese muntjac autosomes had interstitial satellite I sites with four of these autosomal pairs (chromosomes 1, 2 and two other smaller autosomal pairs) also exhibiting interstitial satellite II signals. An interstitial site on the X chromosome was found to have satellite II signals. For the Indian muntjac chromosomes, FISH studies revealed a pericentromeric hybridization for satellites I and II as well as 27 distinct interstitial hybridization sites, each having at least one of the satellite DNAs. These data were used to more precisely de¢ne the chromosome fusion-associated breakpoints that presumably led to the formation of the present-day Indian muntjac karyotype. It further hints at the possibility that the Indian muntjac karyotype may have evolved directly from a 2n 70 ancestral karyotype rather than from an intermediate 2n 46 Chinese muntjac-like karyotype.
Myotonic dystrophy (DM) is an inherited, autosomal dominant muscular disease which is primarily c... more Myotonic dystrophy (DM) is an inherited, autosomal dominant muscular disease which is primarily caused by a CTG trinucleotide expansion mutation on chromosome 19ql3.3. The size of this trinucleotide repeat is related both to the age of onset and to the severity of the clinical manifestation. This disease is very rare in Taiwan, and clinical and genetic study on DM has
Mycotoxins are fungal secondary metabolites with very diversified toxic effects in humans and ani... more Mycotoxins are fungal secondary metabolites with very diversified toxic effects in humans and animals. In the present study, patulin (PAT) and citrinin (CTN), two prevalent mycotoxins, were evaluated for their genotoxic effects and oxidative damage to mammalian cells, including Chinese hamster ovary cells (CHO-K1), human peripheral blood lymphocytes, and human embryonic kidney cells (HEK293). PAT, but not CTN, caused a significant dose-dependent increase in sister chromatid exchange (SCE) frequency in both CHO-K1 and human lymphocytes. PAT also elevated the levels of DNA gap and break in treated CHO-K1. In the single cell gel electrophoresis (SCGE) assay, exposure of HEK293 to concentrations above 15 microM of PAT induced DNA strand breaks; the tail moment values also greatly increased after posttreatment with formamidopyrimidine-DNA glycosylase (Fpg). This suggests that in human cells PAT is a potent clastogen with the ability to cause oxidative damage to DNA. However, no significant change in the tail moment values in CTN-treated cultures was found, suggesting that CTN is not genotoxic to HEK293. Incubation of HEK293 with CTN increased the mRNA level of heat shock protein 70 (HSP70), but not that of human 8-hydroxyguanine DNA glycosylase 1 (hOGG1). PAT treatment did not modulate the expression of either HSP70 or hOGG1 mRNA.
Dysfunctional gap junctions caused by GJB2 (CX26) and GJB6 (CX30) mutations are implicated in nea... more Dysfunctional gap junctions caused by GJB2 (CX26) and GJB6 (CX30) mutations are implicated in nearly half of nonsyndromic hearing loss cases. A recent study identified a heterozygous mutation, c.119C.T (p.A40V), in the GJB6 gene of patients with nonsyndromic hearing loss. However, the functional role of the mutation in hearing loss remains unclear. In this study, analyses of cell biology indicated that a p.A40V missense mutation of CX30 causes CX30 protein accumulation in the Golgi body rather than in the cytoplasmic membrane. The tet-on protein expression system was used for further study of mutant proteins in CX30 and CX30A40V co-expressions and in CX26 and CX30A40V co-expressions. The p.A40V missense mutation exerted a dominant negative effect on both normal CX30 and CX26, which impaired gap junction formation. Moreover, computer-assisted modeling suggested that this p.A40V mutation affects the intra molecular interaction in the hydrophobic core of Trp44, which significantly alters the efficiency of gap junction formation. These findings suggest that the p.A40V mutation in CX30 causes autosomal-dominant nonsyndromic hearing loss. These data provide a novel molecular explanation for the role of GJB6 in hearing loss.
Mutation Research/Reviews in Mutation Research, 1997
A total of 15 newly-developed Bowen's disease patients and 34 age-sex-residence-matched controls ... more A total of 15 newly-developed Bowen's disease patients and 34 age-sex-residence-matched controls were recruited from three arseniasis-hyperendemic villages in Taiwan to compare spontaneous and arsenic-induced sister chromatid exchanges (SCEs), proportion of cells with high frequencies of SCEs (HFCS), and replication index (RI) in their peripheral lymphocytes. Arsenic-induced Bowen's disease patients were found to have significantly higher spontaneous SCEs and HFCs and a lower spontaneous RI than in matched controls without or with adjustment for age, gender, cigarette smoking, alcohol drinking, tea drinking, status of major diseases, HBsAg carrier status and arsenic exposure indices through multivariate analysis. Sodium arsenite was found to increase SCEs and HFCs and to decrease RI in a dose-response pattern for both cases and controls. The arsenic-induced decrease in RI was significantly greater in arsenic-induced Bowen's disease patients than in matched controls. The arsenic-induced increases in SCEs and HFCs were also consistently, but not statistically significantly.
Spinocerebellar ataxia (SCA) type 7 is an autosomal dominant disorder characterized by neural los... more Spinocerebellar ataxia (SCA) type 7 is an autosomal dominant disorder characterized by neural loss, mainly in the cerebellum and regions of the brainstem and particularly the inferior olivary complex. This neurodegeneration disease is associated with expansion of unstable CAG repeats within the 5'-translated region of the SCA7 gene, located on chromosome 3p. We conducted a local survey of the normal population and candidate patients for the analysis of the CAG repeats in the SCA7 gene. The distributions of the CAG repeat units of SCA7 gene in the normal population in Taiwan were established in this study by using the radioactive genomic polymerase chain reaction (PCR). The normal range of CAG repeats is from 6 to 17 repeats, with the more common being around 8-13 repeats. The range is narrower than that reported for other ethnic groups (7-35 CAGs). Meanwhile, by the use of a combination of PCR and Southern blot analysis, one SCA7 family was identified and is reported here. A marked instability of the CAG repeat number during transmission from father to son (41 vs. 100) was observed in the SCA7 family. Clinical anticipation is significant in this family including an infantile case, who was found to have nystagmus from the age of 1 month. To date, the SCA7 mutation has been detected in one of 73 families with autosomal dominant cerebellar ataxia phenotypes, which is about 1.4% of the ataxia families referred to us, compared to 1.4% SCA1, 9.6% SCA2, and 27.3% SCA3/Machado-Joseph disease in our collection. In addition, we demonstrate that the PCR-based Southern blot analysis, with the advantages of sensitivity of PCR and specificity of Southern blot, is a reliable diagnostic method for SCA7 mutation screening. The molecular analysis technique makes possible the quick and accurate diagnosis of SCA7 patients and in the future will hopefully be applied to prenatal screening for SCA7 families.
To investigate the prevalence of human polyomaviruses in Taiwan, urine samples from immunocompete... more To investigate the prevalence of human polyomaviruses in Taiwan, urine samples from immunocompetent (healthy), transient immunocompromised (pregnant), and prolonged immunosuppressed (autoimmune disease) individuals were collected throughout the island. The viral DNA in the urine was detected by the polymerase chain reaction (PCR) and Southern blot. The viral genotypes were determined by DNA sequencing within the regulatory region. The overall results, including cases reported previously, show that 13.3% (10/75) of immunocompetent individuals, 26.0% (20/77) of pregnant women, and 37.5% (18/48) of autoimmune disease patients are JCV positive. All of the immunocompetent individuals are BKV negative, but 3.9% (3/77) of the pregnant women and 6.2% (3/48) of autoimmune disease patients are BKV positive. Twenty-four percent (48/200) of the examined urine samples were JCV positive, but only 3% (6/200) were BKV positive. JCV positive individuals were mainly infected with CY (42%) and TW-1 (52%) subtypes. These results suggest that the incidence of urinary excretion of human polyomaviruses in immunosuppressed individuals is higher than that of immunocompetent individuals. The prevalence of JCV appears to be higher than that of BKV in Taiwan. In addition, CY and TW-1 are the predominant subtypes of JCV prevalent in the Taiwanese population.
Governmental officials as well as medical scientists in Taiwan have worked hard in recent years t... more Governmental officials as well as medical scientists in Taiwan have worked hard in recent years to develop and to implement various measures, such as prenatal diagnosis and neonatal screening, to lower the incidence of hereditary diseases and mental retardation in the population. An inquiry into the possibility of devising a chromosomal and biochemical screening program and to apply it routinely to all the mentally retarded school children island-wide was the major aim of the present study. A collection of 1,614 blood samples was screened for phenylketonuria (PKU), galactosemia, homocystinuria, biotinidase deficiency, and congenital hypothyroidism. The IQ of these children ranged from 50-75 (1,397 children, moderate group) to less than 50 (217 children, severe group). Six cases of PKU (one tetrahydrobiopterin deficient and five classical) and three cases of thyroid dysfunction were found. The overall incidence of these two diseases was 0.56~. Of the 1,614 blood samples, 1,323 were cultured and karyotyped successfully. One hundred and twenty-five of them had chromosome abnormalities. The majority (64 out of 125) were trisomy 21. A remarkable difference in the percentage of mentally retarded children with chromosome abnormalities was observed between the moderate (7.87~) and severe (17.51~) retardates.
Hirschsprung disease (HSCR), or congenital intestinal aganglionosis, is a relatively common disor... more Hirschsprung disease (HSCR), or congenital intestinal aganglionosis, is a relatively common disorder characterized by the absence of ganglion cells in the nerve plexuses of the lower digestive tract, resulting in intestinal obstruction in neonates. Mutations in genes of the RET receptor tyrosine kinase and endothelin receptor B (EDNRB) signaling pathways have been shown to be associated in HSCR patients. In this study, we collected genomic DNA samples from 55 HSCR patients in central Taiwan and analyzed the coding regions of the RET and EDNRB genes by PCR amplification and DNA sequencing. In the 55 patients, an A to G transition was detected in two (identical twin brothers). The mutation was at the end of RET exon 19 at codon 1062 (Y1062C), a reported critical site for the signaling pathways. Single nucleotide polymorphisms (SNP) in exons 2, 7, 11, 13, and 15 of RET and exon 4 of EDNRB in the HSCR patients or controls were detected. The differences between patients and controls in allele distribution of the five RET polymorphic sites were statistically significant. The most frequent genotype encompassing exons 2 and 13 SNPs (the polymorphic sites with the highest percentage of heterozygotes) was AA/GG in patients, which was different from the AG/ GT in the normal controls. Transmission disequilibrium was observed in exons 2, 7, and 13, indicating nonrandom association of the susceptibility alleles with the disease in the patients. This study represents the first comprehensive genetic analysis of HSCR disease in Taiwan.
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Papers by Shuan-yow Li