Biomedical subjects

W C Hsu

Publications and source records attributed to W C Hsu.

At least 19 recordsLinked to original sources

PubMed2006

Apolipoprotein E, angiotensin-converting enzyme and kallikrein gene polymorphisms and the risk of Alzheimer's disease and vascular dementia.

Lipoproteins and vascular factors may play roles in the development of Alzheimer's disease (AD) and/or vascular dementia (VaD). In this study, odd ratios (ORs) and 95% confidence intervals (CIs) for apolipoprotein E (APOE), angiotensin-converting enzyme (ACE), and kallikrein (KLK1) polymorphisms were computed to test their association with the disease by a case-control study. The risk of AD was significantly increased for individuals with APOE varepsilon4 allele (OR = 3.73, 95% CI = 2.38-5.98). The risk of AD was also significant for people with ACE DD genotype, D allele, or T-D haplotype [OR (95% CI) = 4.29 (1.96-10.23), 1.90 (1.35-2.70), or 2.91 (1.71-5.10), respectively]. The above association between ACE-VaD was also strong (p = 0.0012, 0.0050, 0.0007, respectively). Reporter constructs containing the -240 A or T allele displayed similar transcriptional activity in both HEK-293 and IMR-32 cells. Thus, another putative pathogenic marker that is linked with the Alu D allele might affect the risk of AD and VaD in Taiwan.

Alzheimer Disease↗

PubMed2006

Clinical characteristics of multiple sclerosis in Taiwan: a cross-sectional study.

This study reviewed the clinical characteristics of multiple sclerosis (MS) in Taiwanese patients from 1993 to 2001. Of the 75 MS patients with a mean age of onset of 35.6 +/- 12.6 years, the female-to-male ratio was 4.4 (61/14). In 42 (56%) optico-spinal MS (OS-MS) patients, the age of onset (37.6 +/- 11.1 years) tended to be older than conventional MS (C-MS) patients (33.1 +/- 14.1 years, P = 0.08). In 60 cerebrospinal fluid (CSF) specimens, raised IgG index (>0.7) and oligoclonal bands were noted in 26 (43.3%) and two (3.3%) cases, respectively. The frequency of raised IgG index was lower in OS-MS (31.3%) than in C-MS (57.1%, P = 0.07). The CSF total protein concentrations were significantly higher in OS-MS (64.5 mg/dL) than in C-MS (46.6 mg/dL, P = 0.047). The mean annual relapse rate was 54.1%, and was significantly higher within the first year (59.7%, P < 0.001). The mean annual relapse rate in OS-MS (62.7%) was significantly higher than in C-MS (41.2%, P=0.01). The differences in the annual relapse rate and total protein concentration in CSF between OS-MS and C-MS suggest probably two distinct immunopathogenesis. The higher first year relapse rate of MS patients in Taiwan may address the importance of early intervention with immunomodulatory therapy.

Adult↗

PubMed2005

Heat shock protein 70 and tumor necrosis factor alpha in Taiwanese patients with dementia.

This study was to determine whether polymorphisms of heat shock protein 70-1 (HSP70-1) and tumor necrosis factor alpha (TNF-alpha) are associated with the risk of Alzheimer's disease (AD) and vascular dementia (VaD). Using the criteria of the NINCDS-ADRDA and NINDS-AIREN, 125 AD patients, 57 VaD patients and 109 ethnically matched nondemented controls were enrolled. The HSP70-1 -110 A/C and TNF-alpha -1031 T/C, -863 C/A and -857 C/T polymorphisms were analyzed by means of genotype or haplotype association methods. None of the four genotypes examined showed a statistically significant difference in genotype distribution between the AD cases and controls. However, the HSP70-1 -110 CC genotype occurred more frequently among AD cases (p=0.0821; odds ratio: 2.08; 95% confidence interval, CI: 0.92-4.98). The overall genotype distribution among the VaD cases tended to be different at the HSP70-1 -110 and TNF-alpha -1031 sites (p=0.0604 and 0.0316, respectively). The HSP70-1 -110 CC genotype was more frequent (p=0.0459), and the association of the -110 CC genotype with VaD was evident (p=0.0207; odds ratio: 3.22; 95% CI: 1.20-8.87). The more frequent TNF-alpha -1031 TC genotype (p=0.0614) was also evidently associated with VaD (p=0.0209; odds ratio: 2.32; 95% CI: 1.14-4.78). Multivariate analysis demonstrated the synergistic effect of the HSP70-1 -110 CC and TNF-alpha -1031 TC/CC genotypes on VaD (p=0.0091; odds ratio: 10.09; 95% CI: 2.01-75.97). Haplotype analysis among TNF-alpha -1031, -863, -857 sites revealed that -1031C-857C may act as a risk haplotype among VaD cases (p=0.0132, odds ratio: 2.26; 95% CI: 1.19-4.33). Our results suggest a potential protective role for HSP70 in both VaD and AD, whereas TNF-alpha may act as a risk factor only for VaD, and not for AD.

Aged↗

PubMed2005

Prenatal three-dimensional ultrasound and magnetic resonance imaging evaluation of a fetal oral tumor in preparation for the ex-utero intrapartum treatment (EXIT) procedure.

Recent attempts at predelivery management of obstructed fetal airways have focused on the EXIT (ex-utero intrapartum treatment) procedure, which allows sufficient time to secure the fetal airway through preservation of uteroplacental gas exchange. We report a fetus with an exophytic oral tumor noted at 34 weeks of gestation. In this case, three-dimensional (3D) ultrasound allowed a complete and interactive evaluation of the tumor and related facial anatomy, and confirmed that access to the fetal airway was unlikely during delivery. Fetal magnetic resonance imaging (MRI) further demonstrated that the tumor originated in the nasopharynx and obstructed the upper airway. Both imaging results led to a final decision to offer an EXIT procedure for the neonate. At 36 weeks' gestation, a successful EXIT procedure was performed to reduce the risk of respiratory distress immediately after birth. This report highlights the value of 3D ultrasound and MRI as essential prerequisites for optimization of the triage process in selecting EXIT candidates.

Adult↗

PubMed2005

Enhanced sodium absorption in middle ear epithelial cells cultured at air-liquid interface.

CONCLUSION: As we demonstrated previously that transcription of alpha-ENaC was correlated with oxygen tension in the culture medium, this study suggests that the increase in alpha-ENaC expression observed under ALI conditions may result from greater oxygenation of ME cells. OBJECTIVE: The physiology of the middle ear (ME) is primarily concerned with keeping the cavities fluid-free, to allow transmission of sound vibrations from the eardrum to the inner ear. ME epithelial cells are thought to play a key role in this process as they actively absorb sodium and water in order to clear any excess fluid present in the cavities. MATERIAL AND METHODS: As an air-liquid interface (ALI) model has been shown to improve differentiation and enhance sodium absorption in other respiratory epithelia, we established an ALI model for ME cells. RESULTS: ME cells cultured under ALI conditions exhibited a fourfold increase in sodium absorption, which was not related to either a metabolic effect or to enhanced morphological differentiation, but instead to an increase in expression of the alpha-subunit of the epithelial sodium channel (alpha-ENaC).

Absorption↗

PubMed2004

The enhancement of nuclear receptor transcriptional activation by a mouse actin-binding protein, alpha actinin 2.

The p160 coactivators, steroid receptor coactivator 1, glucocorticoid receptor interacting protein 1 (GRIP1) and the activator of thyroid and retinoic acid receptor, have two activation domains, AD1 and AD2, which transmit the activation signal from the DNA-bound nuclear receptor to the chromatin and/or transcription machinery. In screening for mammalian proteins that bind the AD2 of GRIP1, we identified a mouse actin-binding protein, alpha actinin 2 (mACTN2). mACTN2 was expressed in the heart, skeletal muscle, lung, brain and testis, but there was no expression in the spleen, liver or kidney. Interestingly, the expression level of mACTN2 in the developing embryo depended on the embryonic stage. We further demonstrated that mACTN2 could enhance two transactivation activities of GRIP1, which in turn could enhance the homodimerization of mACTN2. Importantly, mACTN2 not only served as a primary coactivator for androgen receptor, estrogen receptor and thyroid receptor activities, but also acted synergistically with GRIP1 to enhance these nuclear receptor (NR) functions. However, the NR binding motif, LXXLL, conserved in mACTN2 and other actinin family proteins, might be a dispensable domain for its coactivator roles in NRs. These findings suggested that mACTN2 might play an important role in GRIP1-induced NR coactivator functions.

Actinin↗

PubMed2003

A feasibility study on the predictive emission monitoring system applied to the Hsinta power plant of Taiwan Power Company.

The continuous emission monitoring system (CEMS) can monitor flue gas emissions continuously and instantaneously. However, it has the disadvantages of enormous cost, easily producing errors in sampling periods of bad weather, lagging response in variable ambient environments, and missing data in daily zero and span tests and maintenance. The concept of a predictive emission monitoring system (PEMS) is to use the operating parameters of combustion equipment through thermodynamic or statistical methods to construct a mathematic model that can predict emissions by a computer program. The goal of this study is to set up a PEMS in a gas-fired combined cycle power generation unit at the Hsinta station of Taiwan Power Co. The emissions to be monitored include nitrogen oxides (NOx) and oxygen (O2) in flue gas. The major variables of the predictive model were determined based on the combustion theory. The data of these variables then were analyzed to establish a regression model. From the regression results, the influences of these variables are discussed and the predicted values are compared with the CEMS data for accuracy. In addition, according to the cost information, the capital and operation and maintenance costs for a PEMS can be much lower than those for a CEMS.

Automation↗

PubMed2001

Cochlear electrical stimulation: influence of age of implantation on Fos immunocytochemical reactions in inferior colliculi and dorsal cochlear nuclei of the rat.

The influence of age at the time of implantation of a stimulating electrode unilaterally in the inner ear on central auditory pathways was investigated in rats deafened shortly after birth. Immunoreactivity for Fos served as a functional marker of neuronal activity. Electrodes were implanted in the left cochlea of rats aged 3 weeks or 4 months. Stimulation lasted 45 minutes, then rats were sacrificed and tissues processed for immunocytochemistry. The younger animals showed significantly more neurons with Fos immunoreactivity bilaterally in the dorsal cochlear nuclei (DCN) and inferior colliculi (IC) than the older rats or control animals with normal hearing receiving the same stimulation. Activity was more prominent in the left DCN and right IC. The results show that electrical stimulation of the inner ear is more effective in younger animals in eliciting gene expression associated with development of a functional network in the auditory pathways. This suggests that deaf children should be provided with cochlear implants as early as possible.

Age Factors↗

PubMed2001

Accumulation of mitochondrial DNA deletions in human oral tissues -- effects of betel quid chewing and oral cancer.

Accumulation of mitochondrial DNA (mtDNA) mutations in human tissues has been associated with intrinsic aging and environmental insult. Recently, mtDNA mutations have been detected in various tumors, including head and neck tumors. However, the factors affecting the occurrence and accumulation of mtDNA deletions in tumor tissues are poorly understood. In Taiwan, betel quid chewing is a major risk factor for oral cancer. Using polymerase chain reaction (PCR) techniques, we examined large-scale deletions of mtDNA in 53 pairs of tumor and non-tumor oral tissues from the patients with or without betel quid chewing history. The results revealed that irrespective of the history of betel quid chewing, the incidences of the 4977bp deletion and other deletions of mtDNA were lower in the tumor portion as compared with the non-tumor portion. The average proportions of the 4977bp deleted mtDNA in the tumor tissues of the betel quid chewers and non-betel quid chewers were 13- and 5-fold, respectively, lower than those in the corresponding non-tumor tissues. Moreover, the average proportion of 4977bp deleted mtDNA was significantly higher (P<0.05) in the non-tumor oral tissues of the patients with betel quid chewing history than that of the patients without the history of betel quid chewing. These results suggest that betel quid chewing may increase mtDNA mutation in human oral tissues and that accumulation of mtDNA deletions and subsequent cytoplasmic segregation of these mutations during cell division could be an important contributor to the early phase of oral carcinogenesis.

Areca↗

PubMed2001

Serous or mucoid effusion in the course of secretory otitis media: influence of ion transport modulation.

OBJECTIVE: Secretory otitis media is defined by a chronic effusion in the middle ear cavities, behind an intact tympanic membrane without acute infection. In the course of secretory otitis media, the effusion is sometimes thick (or mucoid) and other times thin (or serous). For several authors, these differences might be related to different inflammatory levels rather than to distinct pathophysiological mechanisms. The purpose of this study was to determine whether the modulation of ion transport by inflammation could account for the differences observed in the aspect of ME effusion. METHODS: Hydrogen peroxide (H2O2), used as an inflammation model was tested on a middle ear cell line (MESV) in culture. RESULTS: Results show that low and high concentrations of H2O2 have opposite effects on ion (and then water) absorption by the middle ear epithelium. CONCLUSION: the modulation of ion and water absorption by inflammation could modify the mucins concentration in the effusion, and explain observed viscosity differences in the course of secretory otitis media.

Anti-Infective Agents, Local↗

PubMed2001

Specific IgA antibodies to recombinant early and nuclear antigens of Epstein-Barr virus in nasopharyngeal carcinoma.

Nasopharyngeal carcinoma is a common cancer in Taiwan. The Epstein-Barr virus (EBV) is closely associated with nasopharyngeal carcinoma. The sera of patients with nasopharyngeal carcinoma have IgA antibodies to a variety of EBV latent and replicated antigens. Recently, an enzyme-linked immunosorbent assay (ELISA) kit, combining both the EBV early antigen (EA) and nuclear antigen (EBNA-1) became commercially available. The purpose of this study was to assess its clinical application. Serum IgA antibodies to the EBV EA and EBNA-1 were measured by using the ELISA kit in various groups of subjects. Fluorescence antibody (FA) tests against EBV viral capsid antigen (VCA) and EA in the IgA and IgG classes were also studied for comparison. The DNA content analysis was also carried out to investigate the association with IgA antibody titres using ELISA. The sensitivity, specificity and accuracy of the ELISA test were 98.1%, 81.8% and 88.7% respectively. It was far better than any FA tests. The IgA antibody titres showed no association with DNA content analysis. Univariate analysis of various factors revealed that IgA antibody titres were statistically correlated to N stage (P = 0.0291) and M status (P = 0.001). However, there was no association with the age, sex, T stage and clinical stage. Multivariate analysis of various factors was found to be statistically significant in patients with T4 (P = 0.0133), N3 (P = 0.0244) or M1 (P = 0.001) respectively. Serial testing of antibody titres in 22 previously untreated patients found a trend of decreasing IgA antibody titres after initial treatment when the tumours disappeared (P = 0.0358). The ELISA kit to identify specific IgA antibodies with the combination of EBV EA and EBNA-1 recombinant antigens has high sensitivity and acceptable specificity and accuracy in the diagnosis of nasopharyngeal carcinoma. This assay should be useful for early diagnosis and mass screening of patients.

Aged↗

PubMed2001

Failure of grommet insertion in post-irradiation otitis media with effusion.

Nasopharyngeal carcinoma (NPC) survivors with post-irradiation otitis media with effusion (OME; 100 ears) were divided into 2 groups. One group underwent grommet insertion, and the other group was treated by repeated myringotomies plus aspiration to evaluate the outcome of the OME. Computed tomography, magnetic resonance imaging, audiometry, and local checks of the ear, nose, and nasopharyngeal fields were performed to evaluate the sinus and middle ear conditions over a long-term (more than 10 years) follow-up period. The results in these NPC survivors with OME indicated that the prevalence of middle ear complications in the myringotomized group (33%) was less than that in the grommeted group (90%). Grommets alone cannot eradicate inflammation outside the middle ear cavity, but rather, they can aggravate it by superinfection. We therefore recommend that controlling the radiation-induced inflammation in areas such as the ears, nose, sinuses, and nasopharynx is most important. In conclusion, post-irradiation OME should be treated in a different way from conventional OME. Restated, grommet insertion is contraindicated in post-irradiation OME.

Adult↗

PubMed2001

Hyperinsulinemia and insulin resistance related metabolic syndrome.

BACKGROUND: A cross-sectional study in northern Taiwan was conducted to investigate the role of serum insulin level on the development of hyperglycemia, hypertension, obesity and hyperlipidemia. METHODS: Demographic data (age, gender), body mass index, blood pressure, and laboratory blood tests (uric acid, total cholesterol, triglycerides, glucose and immunoreactive insulin when fasting and two hours after loading 75 gm glucose) were collected. A logistic model or polychotomous model, treating each chronic disease (hyperglycemia, hypertension, obesity and hyperlipidemia) as a dependent variable, were fitted to study the effect of serum insulin level. RESULTS: Four hundred and twenty one volunteers (women:men = 237:184) were recruited from 1991 to 1993. Women were more obese and had more hyperglycemia, while the frequency of hyperuricemia was lower than of men. Women with a higher level of the sum of fasting and 2-hour post glucose load insulin (SIRI) levels had higher frequencies of glucose intolerance, hypertension, obesity and hyperlipidemia, whereas SIRI was related to only obesity and hyperlipidemia in men. The high plasma SIRI was a risk factor for both impaired glucose tolerance (IGT) and obesity in women. Men with a high plasma SIRI showed a more than three-fold risk of obesity. CONCLUSIONS: We have observed that a higher serum insulin level was significantly associated with the development of metabolic manifestations (glycemic status and obesity) in a suburban community in northern Taiwan. Men and women with a higher serum insulin level probably had a greater chance of developing obesity, and women had a greater chance of developing IGT.

Adolescent↗

PubMed2001

Computed tomography-guided percutaneous transpedicular biopsy of the thoracic spine.

BACKGROUND: Despite the recent, widespread use around the world of computed tomography (CT)-guided spinal biopsy for presurgical evaluation, its use has remained uncommon in Taiwan. Using 9 patients, we attempted to evaluate the safety of its use for the thoracic spine biopsy. METHODS: In the past 3 years (May 1996 to May 1999), 9 patients with known thoracic or multiple spinal lesions underwent CT-guided biopsy. The patients comprised 4 men and 5 women; with ages ranging between 28 and 85 years. For the transpedicular approach, patients were laid prone on the CT table. A trephine bone biopsy needle set was used after local anaesthesia. The specimens obtained had tissue pathology and/or bacterial/tuberculosis (TB) culture. RESULTS: Excellent results were achieved in 8 of the 9 patients, with no significant procedure-related complications. Among them, 2 were diagnosed as metastatic carcinomas; 3 as osteoporotic compression fractures; 2 were proved to be bacterial or tuberculosis spondylitis and the last one was a healing fracture. CONCLUSION: CT-guided transpedicular trephine biopsy of the thoracic spine is a safe and effective method for preoperative evaluation of various thoracic spinal disorders. Based on the biopsy results, more effective treatment regimens were prescribed and, in turn, better outcomes were expected.

Adult↗

PubMed2000

Genetic risk factors of sporadic Alzheimer's disease among Chinese in Taiwan.

To evaluate the genetic factors for AD among a Chinese population in Taiwan, we studied the polymorphisms of six candidate genes of Alzheimer's disease (AD), including the regulatory region of apolipoprotein E (Apo-E, G-186T), the promoter of apolipoprotein E (Apo-E, A-491T), the bleomycin hydrolase gene (BH, A1450G), a mutation of alpha(2)-macroglobulin gene (A2M G2998A), low-density lipoprotein receptor-related protein gene (LRP, C766T), and alpha(1)-antichymotrypsin gene (ACT, -15Ala/Thr) in AD patients and non-affected elder individuals among Taiwanese Chinese. Eighty-two AD patients and 110 non-affected individuals were recruited for this study. We used polymerase chain reaction (PCR) and restriction enzyme digestion to identify their genotypes. The statistical examination was performed by combining the results of our previous reports - apolipoprotein E epsilon4 (ApoE-4), presenilin-1 intronic polymorphism (PS-1, allele 1/2), and the five-nucleotide deletion of alpha(2)-macroglobulin gene (A2M). Among these nine candidate genes of AD, the ApoE-4 allele is the only independent genetic risk factor for AD. The other candidate genes in this study were not associated with the occurrence of AD. In addition, there are no gene-gene interactions.

Aged↗

PubMed2000

Primary placement of a titanium motility post in a porous polyethylene orbital implant: animal model with quantitative assessment of fibrovascular ingrowth and vascular density.

PURPOSE: To determine whether a Medpor porous polyethylene orbital implant, at the time of initial orbital implant surgery, will tolerate the insertion of a titanium screw on the anterior surface of the implant. METHODS: Twelve New Zealand white rabbits were enucleated and implanted with a porous polyethylene orbital implant. At the time of enucleation, the porous polyethylene orbital implants were drilled, and titanium motility coupling posts were inserted. The motility coupling posts were inserted at two projection heights (2 or 4 mm) and either covered within Tenon capsule/conjunctiva (eight implants) or left exposed (four implants). Rabbits were killed at 6 or 12 weeks. Clinical tissue tolerance, histologic response to the motility coupling post, and vascular density of the porous polyethylene orbital implant were evaluated. RESULTS: The motility coupling posts were well tolerated, and extrusion or migration of the motility coupling post did not occur. The average percentage cross-sectional area of the implant occupied by fibrovascular tissue at 6 and 12 weeks was 76.3% and 97.5%, respectively. In comparing the vascular density (number of vessels per square millimeter) in the porous polyethylene orbital implant within a 1-mm zone immediately surrounding the motility coupling post, no significant difference between this zone and the vascular density found within its entire corresponding annulus was found at either 6 or 12 weeks. CONCLUSIONS: During the 6- and 12-week observation periods, all implanted motility coupling posts demonstrated favorable tissue tolerance and stable interfaces with surrounding tissues. The extent of fibrovascular tissue ingrowth and vascular density verify that initial screw insertion does not adversely affect the healing process after porous polyethylene orbital implant implantation. Thus, primary placement of the motility coupling post may obviate the need for a secondary surgical procedure.

Animals↗

PubMed2000

Inhibition of conjunctival scarring and contraction by a porous collagen-glycosaminoglycan implant.

PURPOSE: To study the healing processes of full-thickness wounds in the adult rabbit conjunctiva after grafting with a porous collagen-glycosaminoglycan (CG) copolymer matrix. METHODS: A 7-mm trephine was used to produce lesions of the bulbar conjunctiva down to the level of the bare sclera. Full-thickness removal of the conjunctiva and Tenon's capsule created a reproducible wound bed. Wounds either remained ungrafted (control) or were grafted with CG matrix. In previous studies, this CG matrix has induced partial regeneration of the dermis in the human, the swine, and the guinea pig. Healing of the conjunctival epithelium and underlying stroma was evaluated by histology, immunohistochemistry, and measurement of wound contraction kinetics. RESULTS: By 28 days, ungrafted wounds had closed by contraction (26.4% +/- 5.0% fornix shortening) and the formation of scarlike tissue comprising an aligned array of dense collagen populated with occasional fibroblasts. Grafting of identical defects with CG copolymer matrix resulted in inhibition of wound contraction (6.8% +/- 3.2% fornix shortening) and the formation of a tissue that resembled normal conjunctival stroma, being composed of a loose network of collagen fibers and fibroblasts. Contractile fibroblasts (myofibroblasts) were identified at the edge of both ungrafted and grafted wounds during the period of active contraction. Both ungrafted and grafted wounds were completely re-epithelialized by 28 days. CONCLUSIONS: Implantation of CG copolymer matrix drastically reduced contraction and promoted the formation of a nearly normal subconjunctival stroma.

Animals↗

PubMed1999

No association of alpha-2 macroglobulin gene five-nucleotide deletion with AD in Taiwan Chinese.

The alpha-2 macroglobulin five-nucleotide deletion (A2M-2) allele frequency was not significantly higher in the AD group than the control group (0.062 versus 0.101, p > 0.1). The odds ratio for AD in individuals with the A2M-2 allele was 0.582 (95% CI, 0.25 to 1.40). These results do not support the association between A2M-2 and AD in the Chinese population, although the allele frequency of A2M-2 is lower than that found in the Caucasian population. Therefore, A2M-2 might not be a significant risk factor of AD among Taiwan Chinese.

Aged↗