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Biomedical subjects

B H Chen

Publications and source records attributed to B H Chen.

At least 37 records · Page 2Linked to original sources
PubMed2001

Seroprevalence and demographic characteristics of HTLV-I among blood donors in Taiwan: 1996-1999.

Screening for the human T-cell lymphotropic virus type I (HTLV-I) and-II in blood donors was implemented in Taiwan beginning in February 1996. The purpose of the present study was to investigate the changes in HTLV-I seroprevalence in all unpaid blood donors in Taiwan during the period from February 1996 to December 1999 and to determine the influence of age and sex on the HTLV-I seropositivity of donors. HTLV-I and HTLV-II screening was performed using combined HTLV-I/II immunoassay. Repeated reactive samples were confirmed by Western blot analysis. Of a total of 3,701,087 donors in all 6 blood centers in Taiwan, 2,311 (0.058%) were seropositive for HTLV-I. The HTLV-I seropositivity was 0.130%, 0.063%, 0.044%, and 0.032% in the years 1996, 1997,1998, and 1999, respectively. There was a linear increase of HTLV-I seropositivity with advancing age. The HTLV-I carrier rate for female donors was twice that for the male donors. Ninty-seven percent of HTLV-I seropositive results came from first-time donors. Our findings suggest that Taiwan is a low-prevalence nonendemic area for HTLV-I infection. The large-scale HTLV-I screening program has decreased HTLV-I seropositivity among blood donors and is useful for preventing HTLV-I transmission via blood transfusion.

Adolescent↗
PubMed2001

GAD65 antibody prevalence and association with thyroid antibodies, HLA-DR in Chinese children with type 1 diabetes mellitus.

Persistent humoral autoimmunity to the enzyme glutamic acid decarboxylase (GAD) has been described in a substantial proportion of patients with type 1 diabetes mellitus. Higher prevalence of GAD antibody in diabetes patients using a new radioligand-binding assay with recombinant human GAD65 antibodies (GAD65Ab) has been seen in several studies. Using this method, we have reassessed the prevalence of GAD65Ab and investigated the association of GAD65Ab with HbA1C values, C-peptide values, HLA-DR typing and thyroid autoimmune antibody in 70 Chinese children with type 1 diabetes mellitus (mean age of onset 8.21+/-3.84 years, mean duration 3.39+/-2.54 years). Our result revealed that GAD65 antibodies were present in 54.3% (38/70) of diabetes children. There was no significant difference in gender, diabetes onset and duration, HbA1c, C-peptide concentration and frequencies of HLA DR3, DR4, DR9, DR3/DR4, DR3/DR9 and DR4/DR9 genotypes between GAD65Ab+ and GAD65Ab- groups. There was no negative correlation between GAD65Ab values and duration of diabetes in those with GAD65Ab positivity (r=-0.239, P>0.05). The frequencies of antimicrosomal and anti-thyroglobulin antibodies in GAD65Ab+ (13.5,8.1%, respectively) were not different from GAD65- patients (9.4,12.5%, respectively).

Adolescent↗
PubMed2001

Formation of polycyclic aromatic hydrocarbons in the smoke from heated model lipids and food lipids.

The contents of polycyclic aromatic hydrocarbons (PAHs) in the smoke from model lipids and food lipids during heating were determined and the mechanism of PAH formation was studied. A Rancimat oil stability analyzer was used as a model system for heating model lipids and food lipids at 220 degrees C for 2 h and for adsorption of smoke. The various lipid degradation products and PAHs in the smoke were identified and quantified by a GC/MS technique. Results showed that model lipids were more susceptible to smoke formation than food lipids during heating, but the PAH levels were lower for the former than latter. Methyl linolenate produced the highest amount of PAHs, followed by methyl linoleate, methyl oleate, and methyl stearate. Also, soybean oil generated a larger amount of PAHs than canola oil or sunflower oil. Benzene-like compounds were found to be possible precursors for PAHs formation. Several PAH derivatives were also present in heated model lipids and food lipids.

Adsorption↗
PubMed2001

Primary hyperparathyroidism and acute pancreatitis during the third trimester of pregnancy.

The simultaneous occurrence of maternal primary hyperparathyroidism (PHPT) and acute pancreatitis during pregnancy is very rare. We report a case of concurrent PHPT and pancreatitis during the third trimester of pregnancy. A summary of the relevant literature regarding the clinical course and recommended management in relation to this case is also presented.

Acute Disease↗
PubMed2001

Comparison of biomechanical response to surgical procedures used for cervical radiculopathy: posterior keyhole foraminotomy versus anterior foraminotomy and discectomy versus anterior discectomy with fusion.

The objective of this study was to compare the change in flexibility of C5-C6 caused by three procedures using a three-dimensional nonlinear finite element model: posterior foraminotomy (keyhole procedure), anterior foraminotomy with discectomy, and anterior discectomy with fusion. The keyhole procedure produced a minor increase in motion. The anterior foraminotomy and discectomy produced one to two times greater motion. Anterior discectomy with fusion produced 50% to 100% reduction in motion. The posterior keyhole foraminotomy has a much lesser effect on the stability of the cervical spine segment than does an anterior procedure, and fusion is a requisite part of the anterior decompression procedure.

Biomechanical Phenomena↗
PubMed2001

Intrafamilial transmission and risk assessment of HTLV-I among blood donors in southern Taiwan.

The human T-lymphotropic virus type I (HTLV-I) is one of the important etiological agents of adult T-cell leukemia/lymphoma and of HTLV-I associated myelopathy or tropical spastic paraparesis. There is still a lack of data concerning HTLV-I transmission by seropositive carriers in Taiwan. We investigated the patterns of HTLV-I intrafamilial transmission in HTLV-I seropositive blood donors and assessed the risk factors of HTLV-I transmission in relatives of HTLV-I carriers in Taiwan. A total of twenty HTLV-I seropositive donors and their 103 relatives were enrolled. Among those 103 relatives, 40 (38.8%) were seropositive for HTLV-I. Their ages ranged from one to 70 years old with a mean age of 31.0 +/- 1.65 year-old. Three of the ten wives of male carriers were HTLV-I seropositive. However, none of the six husbands of female carriers were HTLV-I seropositive. Mother-to-child vertical transmission was found in nine of 48 (18.8%) tested. Significant risk factors of HTLV-I transmission among relatives of HTLV-I carriers were hospital admission, previous transfusion, breast feeding, anti-HCV seropositivity and female relatives of age >/= 30 with odds ratio (OR) of 9.73, 8.64, 4.36, 8.86 and 4.91, respectively (all p < 0.05). Nonsignificant risk factors of HTLV-I transmission were sharing needles, operation history, HBsAg seropositivity and male relatives of age >/= 30. Our findings suggest that mother-to-child and husband-to-wife transmissions are the important forms of intrafamilial transmission of HTLV-I in Taiwan. Screening for HTLV-I in family members of HTLV-I seropositive blood donors may be warranted.

Adult↗
PubMed2001

Prenatal diagnosis of der(11)t(11;18)(q24;q21.3) due to paternal balanced translocation and both parents are carriers of alpha-thalassemia-1--a case report.

A couple were identified as alpha-thalassemia-1 carriers (father: alpha-thal-1 of Filipino type, mother: alpha-thal-1 of SEA type). Amniocentesis was done at 19 weeks of gestation by a local obstetrician. Molecular study of amniotic fluid presented a non-thalassemia fetus, but the cytogenetic study revealed a karyotype of 46,XX,der(11)t(11;18)(q24;q21.3), resulting from a paternal balanced reciprocal translocation and unbalanced adjacent 1 segregation. The pregnancy was terminated at 23 weeks of gestation. The gross of fetus revealed bilateral cleft lip and palate, hypertelorism, flat nasal bridge, frontal bossing, micrognathia, low set ears, short neck with cystic hygroma, overlapping fingers, prominent heels, and limited hip abduction. The chromosome complement of the present case was partial monosomy for 11q24-qter and partial trisomy for 18q21.3-qter. This is the first prenatal diagnosis of unbalanced translocation with der(11)t(11;18)(q24;q21.3) pat due to paternal balanced translocation and both parents being carriers of alpha-thalassemia-1.

Adult↗
PubMed2000

Anterior cervical fusion: a finite element model study on motion segment stability including the effect of osteoporosis.

STUDY DESIGN: Three-dimensional, nonlinear finite element models were used to evaluate the stability of the mid cervical spine after anterior fusion in patients with and without osteoporosis. OBJECTIVES: The objective of this study was to compare the change in flexibility of C5-C6 after anterior discectomy with both loose-fitting and tight-fitting fusion graft. SUMMARY OF BACKGROUND DATA: Many factors such as surgical technique, osteoporosis, and excess neck motion during the postoperative period may contribute to fusion failure. Knowledge about changes in biomechanical properties after the surgical procedure is important for selection of grafts with appropriate strength and for guiding patients in postoperative care and rehabilitation. METHODS: Analyses with anterior fusion models with both loose-fitting and tight-fitting graft were performed in a normal and an osteoporotic spine. The motion of the C5 vertebra in relation to the C6 vertebra were calculated, after multidirectional moment loads of 0.5 Nm combined with a compressive preload of 105 N. RESULTS: Loose-fitting graft produced both an increase and a decrease in motion under various external moment loads, with graft compressive stress below the compressive strength of the graft material. A reduction in motion was observed under all moment loads when a tight-fitting graft was used. The compressive stress in the tight-fitting graft was higher than the strength of the graft material. Osteoporosis increased the principal motions with both the loose-fitting graft and tight-fitting graft. Maximum increase in motion with a loose-fitting graft construct was observed under extension and axial torsion moment loads. CONCLUSIONS: Anterior discectomy and insertion of the loose graft resulted in increased motion. A tight-fitting graft is beneficial in reducing motion, but the stress within the graftincreases beyond the graft strength. The presence of osteoporosis was nominally significant when the graft was tight fitting.

Adult↗
PubMed2000

Synthesis and magnetic and transport properties of Sr6V9S22O2: "AM2S5" phases revisited.

The compound Sr6V9S22O2 was prepared from SrS, sulfur, vanadium metal, and V2O5 at 950 degrees C in an evacuated quartz tube. The compound is rhombohedral, R3, with a = 8.7538(6) A, c = 34.934(3) A, and Z = 3, and shows strong preferred orientation in its XRD profiles (00l) due to the layered nature of the structure. The compound contains charged CdI2 type VS2 layers of formula [V7S14]4- separated by [Sr6(VOS3)2(S2)]4+ layers. The latter has VOS3(3-) tetrahedra and S2(2-) disulfide units linked by Sr2+ ions. Magnetic susceptibility and four-probe resistivity studies show essentially temperature-independent paramagnetism above 80 K and small gap semiconductor behavior, respectively. The compound has a positive Hall coefficient at room temperature. The relationship among Sr6V9S22O2, "SrV2S5" (J. Solid State Chem. 1996, 126, 189), and other AM2S5 phases is discussed.

Journal Article↗
PubMed2000

Analysis and stability of carotenoids in the flowers of daylily (Hemerocallis disticha) as affected by various treatments.

The analysis and stability of carotenoids in the flowers of daylily (Hemerocallis disticha) as affected by soaking and drying treatments were studied. The various carotenoids in the flowers of daylily were analyzed using a reversed-phase C(30) HPLC column and a mobile phase of methanol/methylene chloride/2-propanol (89:1:10, v/v/v) with methanol/methylene chloride (45:55, v/v) as sample solvent. Twenty-one pigments were resolved, of which 14 carotenoids were identified, including neoxanthin, violaxanthin, violeoxanthin, lutein-5,6-epoxide, lutein, zeaxanthin, beta-cryptoxanthin, all-trans-beta-carotene, and their cis isomers, based on spectral characteristics and Q ratios. Prior to hot-air-drying (50 degrees C) or freeze-drying, some of the daylily flowers were subjected to soaking in a sodium sulfite solution (1%) for 4 h. Under either the hot-air- or the freeze-drying treatment, the amounts of most carotenoids were higher in the soaked daylily flowers than in those that were not soaked. With hot-air-drying, the amount of cis carotenoids showed a higher yield in soaked samples than in nonsoaked samples. However, with freeze-drying, only a minor change of each carotenoid was observed for both soaked and nonsoaked samples. Also, air-drying resulted in a higher loss of carotenoids than freeze-drying.

Air↗
PubMed2000

Potential dengue virus-triggered apoptotic pathway in human neuroblastoma cells: arachidonic acid, superoxide anion, and NF-kappaB are sequentially involved.

Direct in vivo evidence for the susceptibility of human neuronal cells to dengue virus has not been reported. In this study, we demonstrated that type 2 dengue (DEN-2) virus infection induced extensive apoptosis in the human neuroblastoma cell line SK-N-SH. Phospholipase A(2) (PLA(2)) was activated by DEN-2 infection, which led to the generation of arachidonic acid (AA). Inhibition of PLA(2) activity by the PLA(2) inhibitors, AACOCF(3) and ONO-RS-082, diminished DEN-2 virus-induced apoptosis. In contrast, the cyclooxygenase inhibitors aspirin and indomethacin, thought to increase AA accumulation by blocking AA catabolism, enhanced apoptosis. Exogenous AA induced apoptosis in a dose-dependent manner. Superoxide anion, which is thought to be generated through the AA-activated NADPH oxidase, was increased after infection. Pretreatment with superoxide dismutase (SOD) protected cells against DEN-2 virus-induced apoptosis. Furthermore, generation of superoxide anion was blocked by AACOCF(3). In addition, the transcription factors, NF-kappaB and c-Jun, were found to be activated after DEN-2 virus infection. However, pretreatment of cells with oligodeoxynucleotides containing NF-kappaB, but not c-Jun, binding sites (transcription factor decoy) strongly prevented dengue virus-induced apoptosis. The finding that AACOCF(3) and SOD significantly block activation of NF-kappaB suggests that this activation is derived from the AA-superoxide anion pathway. Our results indicate that DEN-2 virus infection of human neuroblastoma cells triggers an apoptotic pathway through PLA(2) activation to superoxide anion generation and subsequently to NF-kappaB activation. This apoptotic effect can be either directly derived from the action of AA and superoxide anion on mitochondria or indirectly derived from the products of apoptosis-related genes activated by NF-kappaB.

Animals↗
PubMed2000

Formation of heterocyclic amines in fried fish fiber during processing and storage.

The formation of heterocyclic amines (HAs) in fried fish fiber during processing and storage was studied. Fried fish fiber was prepared by boiling of raw fish, followed by eviscerating, pressing, chopping, and then the fish meat was subjected to frying, during which the various additives such as sugar, soybean sauce, and edible oil were added. The various HAs in fried fish fiber were analyzed by high-performance liquid chromatography with photodiode-array detection. Only four HAs, Norharman, Harman, 2-amino-9H-pyrido[2,3-b]indole, and 2-amino-3-methyl-9H-pyrido[2,3-b]indole were detected in fried fish fiber. The amount of HAs increased with increasing frying temperature. Amino acids might play a more important role for HA formation than reducing sugar during processing of fried fish fiber. During storage, the HAs increased with increasing storage temperature when the fried fish fiber was packed in an aluminum foil bag. However, the relationship between storage temperature and HAs formation was not consistent when the fried fish fiber was packed in a plastic bag.

Amines↗
PubMed2000

Coexistent insulin dependent diabetes mellitus and hyperthyroidism in a patient with Down's syndrome.

The prevalence of thyroid disease is increased in Down's syndrome. Compared with adults, thyroid dysfunction in children with Down's syndrome is less frequently reported. Insulin dependent diabetes mellitus is also uncommon in Down's syndrome children. Coexistent insulin dependent diabetes mellitus and hyperthyroidism in Down's syndrome was only reported once previously in literature. We report an 8-year-old girl with Down's syndrome that had polyuria, polydipsia, abdominal pain and urinary incontinence one and half a month prior to admission. Physical examination revealed typical face of Mongolism and tachycardia. Thyroid glands were not palpable. Laboratory data revealed diabetic ketoacidosis with plasma glucose: 860 mg/dl. She had thyroid hyperfunction with TSH: < 0.1 microU/ml, T3: 219.7 ng/dl, T4: 15 micrograms/dl. Thyroid autoimmune antibodies were also increased. There was markedly increased radiotracer uptake in the bilateral thyroid glands in Tc-99 thyroid scan. We suggest that Down's syndrome children with insulin dependent diabetes mellitus should be evaluated carefully for thyroid function and autoimmune disease.

Child↗
PubMed2000

Acute lymphoblastic leukemia in one of two siblings with Alstrom syndrome.

Alstrom syndrome is a rare autosomal recessive disease; less than 60 cases have been reported. No Chinese patient with this disease has been reported previously in the literature. Here, we describe an 11-year-old Chinese boy with this condition. His elder sister also had Alstrom syndrome, and his father had non-insulin-dependent diabetes mellitus. Both siblings had degenerative retinopathy, obesity, mental retardation, perceptive hearing loss, short stature, non-insulin-dependent diabetes mellitus, nephropathy, hyperlipidemia, acanthosis nigricans, and hepatic dysfunction. The boy also developed acute lymphoblastic leukemia, which was confirmed by cytochemistry and immunophenotyping findings. He received chemotherapy and radiotherapy for the malignancy. The present case suggests that acute lymphoblastic leukemia may be coincident with or may be a previously undescribed systemic manifestation of Alstrom syndrome.

Adolescent↗
PubMed2000

The influence of age and gender on HLA-DR in Chinese child-onset type 1 diabetes mellitus patients.

To further clarify the association of HLA DR alleles with type 1 diabetes mellitus and the influence of age-onset and gender on type 1 diabetes, we investigated HLA-DR in 76 child onset Chinese (36 males) type 1 diabetes patients and 154 normal controls by using PCR-SSP (sequence specific primer). The mean age of onset of diabetes patients was 8.43 +/- 3.96 year-old. Our results revealed that the frequencies of DR3, DR4 and DR9 in diabetes patients were significantly higher than those in control group (all P < 0.01). The susceptible alleles were DR3, DR4, DR9, with relative risks of 8.25, 2.57 and 2.67, respectively. The protective alleles to type 1 diabetes were DR 2, DR8, DR11 and DR12 with relative risk of 0.24, 0.15, 0.16 and 0.39, respectively. There were no significant differences between the frequencies of HLA DR 3, DR4, DR9, DR3/4, DR3/9 and DR4/9 in male and female diabetic children. We divided the diabetes patients into three groups according to their age of onset (1-5 years old, 6-10 years old and 11-17 years old). There was a trend that the frequencies of DR9 decreased with the increase of age at onset, but there was no significant difference of DR3, DR4, DR9, DR3/4, DR3/9 and DR4/9 frequencies between diabetes children with age onset 0-10 years and 11-17 years. As to the influence of gender on the HLA genotypes, the frequency of DR3/4 decreased with the increase of age at onset for male patients and the frequency of DR3/4 increased with the increase of age at onset for female patients.

Adolescent↗
PubMed2000

Comparison of appendectomy medical expense and clinical outcome between fee for service and prospective payment system.

Since the introduction of national health insurance on March 1st 1995 in Taiwan, another 9 items (including appendectomy) were introduced into the Taiwan/prospective payment system (T/PPS). The modified T/PPS was based on those complicated appendectomy cases with secondary diagnosis or second operation where a total fee over 37,500 New Taiwan (NT) dollars was paid by National Health Insurance Bureau (NHIB) according to the real cost. The T/PPS was implemented in October 1997 due to the continuously increasing financial burden of medical expenses on the NHIB. The purpose of this study is (1) to compare the length of stay (LOS) and total medical expense of appendectomy of fee for service (FFS) and T/PPS and (2) to compare the clinical outcome of wound healing after discharge of the two systems by telephone interview. Our study investigated 100 consecutive appendectomy cases under FFS payment system and 99 consecutive appendectomy cases under T/PPS. We retrospectively analyzed LOS, operation time, and hospital cost of different items through chart review and computer data. Our results revealed that the LOS and operation time of T/PPS were significantly shorter than those of FFS (both p < 0.01). The total hospital cost, fee for room service, treatment, pharmacy, examination and anesthesia in T/PPS were also significantly less than those in FFS (all p < 0.01, except for anesthesia p < 0.05). There existed positive correlation between total hospital cost and LOS, operation time, fee for room service, treatment, pharmacy, examination and anesthesia both for T/PPS and FFS. To evaluate the clinical outcome of appendectomy between T/PPS and FFS, we interviewed 73 T/PPS cases and 73 FFS cases by telephone and chart review. Our results revealed that there were no significant differences in frequencies of having painful incision, clear incision wound on the day of discharge, and removal of stitches at hospital (p all > 0.05). We concluded that compared to FFS, T/PPS can decrease LOS and total hospital cost of appendectomy, and T/PPS's clinical outcome of appendectomy in T/PPS showed no significant difference from that in FFS.

Adult↗