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Biomedical subjects

S M Wang

Publications and source records attributed to S M Wang.

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

The C677T mutation of the methylenetetrahydrofolate reductase gene is not associated with the risk of coronary artery disease or venous thrombosis among Chinese in Taiwan.

OBJECTIVES: We sought to investigate the association between the methylenetetrahydrofolate reductase (MTHFR) gene C677T mutation and the risk of coronary artery disease (CAD), myocardial infarction (MI) and venous thrombosis (VT) in a Chinese population in Taiwan. METHODS: The subjects included 218 CAD patients, 107 VT patients, and their age- and sex-matched controls. DNA was extracted from the blood and genotypes were determined by polymerase chain reaction, restriction mapping with HinfI and gel electrophoresis. RESULTS: The distribution of MTHFR genotypes was similar in the CAD cases and controls; the genotype TT was present in 6.0% of CAD patients, as compared to 6.9% of CAD control subjects (p = 0.165; odds ratio = 0. 86; 95% confidence interval = 0.40-1.85). The frequency of the T allele was also similar in CAD cases and controls (25.5% vs. 24.8%; p = 0.788). There was no significant association between TT homozygosity and the risk of MI. The genotype distributions and the frequency of the T allele were also similar in VT cases and controls. CONCLUSIONS: Our data suggest that there is no association between the C677T mutation of the human MTHFR gene and the risk of CAD or VT among Chinese in Taiwan.

Alleles↗
PubMed2001

Generation of high-quantity and quality tag/ditag cDNAs for SAGE analysis.

The serial analysis of gene expression (SAGE) technique is an important tool for genome-wide gene expression analysis. However, the requirement of a large amount of mRNA for the analysis and the difficulties in generating high-quality tag and ditag fragments for the construction of a SAGE library often interfere with the successful performance of the SAGE technique. We developed two procedures to solve these issues: (i) introducing low-cycle PCR amplification of the 3' cDNA before the BsmFI digestion of the 3' cDNAs and (ii) gel purifying the BsmFI-released tag fragments before ditag formation. These modifications provide a large quantity of initial 3' cDNAs and high-quality tags and ditags for the construction of SAGE libraries.

Cloning, Molecular↗
PubMed2001

Characteristics of repeated ambulance use in an urban emergency medical service system.

BACKGROUND AND PURPOSE: Although many studies have examined the reasons for repeated use of emergency medical service (EMS), little information is available concerning repeated ambulance use in Taiwan. This study evaluated the characteristics of repeated EMS ambulance use in an urban EMS system in Taiwan. METHODS: Data from a local EMS computerized database for the period from January 1996 through December 1998 were collected for analysis. All calls to the dispatch center that resulted in EMS transports were included. Repeat users were identified by matching the user name, sex, age, and home address. Transports were categorized according to how many times the patient was transported by ambulance during the 3-year period: single use, one time; repeated use, two or three times; or frequent use, more than three times. RESULTS: During the 36-month study period, there were 41,792 calls, with 13,076 non-transports (a non-transport rate of 31.3%). Of the 28,716 transports during the study period, 2,101 represented repeated or frequent use (7.3%); the rate of frequent use was 1.4% (406/28,716). The frequency of repeated use reached a daily first peak at 8:00 AM, with the second and third peaks at 1:00 PM and 7:00 PM. The mean age increased with increasing repeated use of transport (37.25 +/- 0.24 vs 41.55 +/- 1.03 vs 46.23 +/- 1.57 years, respectively; p < 0.001). The percentage of non-trauma missions increased with increasing repeated use of transport (26.3% vs 55.6% vs 73.2%; p < 0.001). Response time significantly increased for repeated use (analysis of variance [ANOVA], p < 0.001). The on-scene interval (time from arrival until departure) in the single-use group was shorter than in the repeated and frequent use groups (ANOVA, p < 0.005). CONCLUSIONS: The results of this study indicate that the characteristics of repeat users of EMS transport differ from those of single users. Characteristics of service time, reason for transport, and interval to each subsequent call varied among different groups of users. Studies of repeat use under a wider range of conditions such as in rural EMS systems and after implementation of a priority-dispatch system are needed to determine the implications of repeated ambulance use.

Ambulances↗
PubMed2000

Transcriptional activation of estrogen receptor alpha in human breast cancer cells by histone deacetylase inhibition.

Recent findings have established a connection between DNA methylation and transcriptionally inactive chromatin characterized by deacetylated histones. Because the absence of estrogen receptor alpha (ERalpha) gene expression has been associated with aberrant methylation of its CpG island in a significant fraction of breast cancers, we tested whether histone deacetylase activity contributes to the transcriptional inactivation of the methylated ER gene in a panel of ER-negative human breast cancer cells. Treatment of these cells with trichostatin A, a specific histone deacetylase inhibitor, led to dose- and time-dependent re-expression of ER mRNA as detected by reverse transcription-PCR without alteration in ERalpha CpG island methylation. Trichostatin A-induced ER re-expression was associated with increased sensitivity to DNase I at the ER locus in MDA-MB-231 cells. These data implicate inactive chromatin mediated by histone deacetylation as a critical component of ER gene silencing in human breast cancer cells. Therefore, histone deacetylation may be a potential target for therapeutic intervention in the treatment of a subset of ER-negative breast cancers.

Base Sequence↗
PubMed2000

Shark cartilage extract interferes with cell adhesion and induces reorganization of focal adhesions in cultured endothelial cells.

In this study, we examined the effects of shark cartilage extract on the attachment and spreading properties and the focal adhesion structure of cultured bovine pulmonary artery endothelial cells. Treatment with cartilage extract resulted in cell detachment from the substratum. Immunofluorescence staining of those treated cells that remained attached showed that, instead of being present in both central and peripheral focal adhesions as in control cells, both integrin alpha(v)beta(3) and vinculin were found only in peripheral focal adhesion and thinner actin filament bundles were seen. In addition to causing cell detachment, cartilage extract partially inhibited the initial adherence of the cells to the substratum in a dose-dependent manner. Integrin alpha(v)beta(3) and vinculin staining of these cells also showed a peripheral focal adhesion distribution pattern. Vitronectin induced cell spreading in the absence of serum, but was blocked by simultaneous incubation with cartilage extract, which was shown to inhibit both integrin alpha(v)beta(3) and vinculin recruitment to focal adhesion and the formation of stress fibers. Dot binding assays showed that these inhibitory effects on cell attachment and spreading were not due to direct binding of cartilage extract components to integrin alpha(v)beta(3) or vitronectin. Shark cartilage chondroitin sulfate had no inhibitory effect on either cell attachment or spreading of endothelial cells. These results show that the inhibitory effects of cartilage extract on cell attachment and spreading are mediated by modification of the organization of focal adhesion proteins.

Acid Phosphatase↗
PubMed2000

Color Doppler vascularity index can predict distant metastasis and survival in colon cancer patients.

The purpose of this study was to investigate the clinical usefulness of the color Doppler vascularity index (CDVI) in patients with colon cancer before surgery. Forty-four patients with sonographically visible tumor mass of colon cancer were investigated. The CDVI of each tumor was determined using transabdominal color Doppler ultrasound. The CDVI was defined as the ratio of the number of the colored pixels within a tumor section to the number of total pixels in that specific tumor section and was calculated by using Encomate software (Electronic Business Machine Co. Ltd., Taipei, Taiwan). The correlation between the CDVI and clinicopathological factors, mode of recurrence, and patient survival was studied. For comparison, microvessel density (the mean number of microvessels in three areas of highest vascular density at x200 magnification) of the tumors of these 44 patients was also evaluated by using immunohistochemical staining of surgical specimens with anti-CD34. The microvessel density was not correlated with Dukes' classification, clinicopathological factors, and survival. The CDVI was significantly higher in the patients with lymph node metastases and vascular invasion than in those without such metastases and invasion (P = 0.006 and P = 0.0098, respectively). Moreover, in patients with a high CDVI (> 15%) and positive vascular invasion, survival was significantly poorer than in those with low CDVI (< or = 15%) and negative invasion (P = 0.0037 and 0.0039, respectively). Multivariate analysis indicated that liver metastasis, vascular invasion, and CDVI are independent prognostic factors in the patients with colon cancer. According to the mode of recurrence in 36 patients who underwent curative resection, the frequency of the distant organ recurrence was significantly higher in the high CDVI group (40%) than in the low CDVI group (0%). The CDVI is a good preoperative indicator of recurrence and patient survival in colon cancer. Thus, the CDVI may be helpful in stratifying patients for adjuvant therapy.

Adult↗
PubMed2000

Screening poly(dA/dT)- cDNAs for gene identification.

Many genes expressed in the human genome have not been identified despite intensive efforts. We observed that the presence of long poly(dA/dT) sequences in the 3' end of cDNA templates contributes significantly to this problem, because the hybrids formed randomly between poly(dA) and poly(dT) sequences of unrelated cDNA templates lead to loss of many templates in the normalization/subtraction reactions. The low abundant copies, which account for the majority of the expressed genes, are affected in particular by this phenomenon. We have developed a strategy called screening poly(dA/dT)(-) cDNAs for gene identification to overcome this obstacle. Applying this strategy can significantly enhance the efficiency of genome-wide gene identification and should have an impact on many functional genomic studies in the postgenome era.

Base Sequence↗
PubMed2000

Generation of longer cDNA fragments from serial analysis of gene expression tags for gene identification.

We have developed a technique called the generation of longer cDNA fragments from serial analysis of gene expression (SAGE) tags for gene identification (GLGI), to convert SAGE tags of 10 bases into their corresponding 3' cDNA fragments covering hundred bases. A primer containing the 10-base SAGE tag is used as the sense primer, and a single base anchored oligo(dT) primer is used as an antisense primer in PCR, together with Pfu DNA polymerase. By using this approach, a cDNA fragment extending from the SAGE tag toward the 3' end of the corresponding sequence can be generated. Application of the GLGI technique can solve two critical issues in applying the SAGE technique: one is that a longer fragment corresponding to a SAGE tag, which has no match in databases, can be generated for further studies; the other is that the specific fragment corresponding to a SAGE tag can be identified from multiple sequences that match the same SAGE tag. The development of the GLGI method provides several potential applications. First, it provides a strategy for even wider application of the SAGE technique for quantitative analysis of global gene expression. Second, a combined application of SAGE/GLGI can be used to complete the catalogue of the expressed genes in human and in other eukaryotic species. Third, it can be used to identify the 3' cDNA sequence from any exon within a gene. It can also be used to confirm the reality of exons predicted by bioinformatic tools in genomic sequences. Fourth, a combined application of SAGE/GLGI can be applied to define the 3' boundary of expressed genes in the genomic sequences in human and in other eukaryotic genomes.

Cloning, Molecular↗
PubMed2000

Sonographic detection of delayed small bowel perforations after blunt abdominal trauma.

Isolated perforations of the small bowel resulting from blunt abdominal trauma are rare and difficult to diagnose because of their variable presentation, especially when their appearance is delayed. We report 2 such cases that were diagnosed by sonography and emphasize the usefulness of sonography in detecting bowel injuries after blunt abdominal trauma.

Abdominal Injuries↗
PubMed2000

Role of desmin filaments in chicken cardiac myofibrillogenesis.

Desmin filaments are muscle-specific intermediate filaments located at the periphery of the Z-discs, and they have been postulated to play a critical role in the lateral registration of myofibrils. Previous studies suggest that intermediate filaments may be involved in titin assembly during the early stages of myofibrillogenesis. In order to investigate the putative function of desmin filaments in myofibrillogenesis, rabbit anti-desmin antibodies were introduced into cultured cardiomyocytes by electroporation to perturb the normal function of desmin filaments. Changes in the assembly of several sarcomeric proteins were examined by immunofluorescence. In cardiomyocytes incorporated with normal rabbit serum, staining for alpha-actinin and muscle actin displayed the typical Z-line and I-band patterns, respectively, while staining for titin with monoclonal anti-titin A12 antibody, which labels a titin epitope at the A-I junction, showed the periodic doublet staining pattern. Staining for C-protein gave an amorphous pattern in early cultures and identified A-band doublets in older cultures. In contrast, in cardiomyocytes incorporated with anti-desmin antibodies, alpha-actinin was found in disoriented Z-discs and the myofibrils became fragmented, forming mini-sarcomeres. In addition, titin was not organized into the typical A-band doublet, but appeared to be aggregated. Muscle actin staining was especially weak and appeared in tiny clusters. Moreover, in all ages of cardiomyocytes tested, C-protein remained in the disassembled form. The present data suggest the essential role of desmin in myofibril assembly.

Actinin↗
PubMed2000

Vibrio vulnificus infection complicated by acute respiratory distress syndrome in a child with nephrotic syndrome.

A 9-year-old girl with nephrotic syndrome visited a local hospital after developing fever, chills, and edematous changes and multiple hemorrhagic bullae on both legs over 2 days. Cultures of blood and an aspirate from the bullae yielded Vibrio vulnificus. The patient was transferred to our hospital because of persistent fever, generalized edema, acute renal failure, and disseminated intravascular coagulopathy. We treated this patient as a V. vulnificus infection complicated with necrotizing fasciitis. With minocycline and ceftazidime combination therapy was instituted. Emergency fasciotomy and continuous peritoneal dialysis were performed. The patient developed acute respiratory distress syndrome (ARDS) during the hospitalization, requiring intubation and mechanical ventilation. She eventually died. The histopathological findings showed diffuse alveolar damage with lobular pneumonitis. Hyaline membranes, composed of proteinaceous exudate and cellular debris, covered the alveolar surfaces. Microscopic examinations of lung could not distinguish the effects of cytolysin from other insults to lungs that occur in ARDS. This report highlights the postmortem pathological findings in V. vulnificus infection in a child with nephrotic syndrome complicated by ARDS.

Acute Disease↗
PubMed2000

Sequence and mechanical implications of titin's PEVK region.

A widely used titin monoclonal antibody (9D10) was epitope mapped to the PEVK region in the I-band portion of titin. Sequence analysis of the titin PEVK region revealed a large number of 28 amino acid modules (termed "PPAK" repeats) alternating with glutamic acid rich segments. Species differences in cardiac rest tension could not be ascribed to differences in the PEVK length of the N2B titin isoform. The low rest tension generated by dog cardiac muscle also does not appear to be explained by the N2 and PEVK segment lengths in the N2A titin isoform.

Amino Acid Sequence↗
PubMed2000

An outbreak of enterovirus 71 infection in Taiwan, 1998: epidemiologic and clinical manifestations.

BACKGROUND: An outbreak of enterovirus infections occurred throughout Taiwan in 1998. The diseases were manifectated with hand, foot, and mouth disease (HFMD), some associated with meningitis, encephalitis, or acute flaccid paralysis (AFP). OBJECTIVES: This study is aimed to characterize and analyze the epidermologic and clinical features during the outbreak. STUDY DESIGN: The epidemiologic information was collected from the Ministry of Health on passive surveillance; clinical and virological investigations were carried out at National Cheng Kung University Medical Center. RESULTS: Between April and December 1998, 405 children were hospitalized, and 78 patients died during this outbreak in Taiwan. There were 119 cases identified to be EV71 infection in Tainan and Chiayi areas; 105 cases by virus isolation and 14 by serological assay. The outbreak had a biphasic curve with peak in June and October, especially in the southern Taiwan. Seventy-two percent of patients were below 3 years of age. The spectrum of disease included HFMD in 54, HFMD with central nerve system (CNS) involvement in 37, herpangina in 12, aseptic meningitis in three, encephalitis/ meningoencephalitis in ten, acute flaccid paralysis in three. There was nine fatal cases complicated with neurogenic pulmonary edema. Myoclonus with sleep disturbance was the most important early sign of EV71 infection with CNS involvement. CONCLUSION: Our experience demonstrated that the EV71 isolated in Taiwan had strong dermatotropic as well as neurotropic tendencies. Early detecting CNS involvement and commencing aggressive therapy may reduce the mortality.

Adolescent↗
PubMed2000

Magnolol stimulates steroidogenesis in rat adrenal cells.

1. This study investigated the effect of magnolol, a compound purified from Magnolia officinalis, on glucocorticoid production by primary adrenal cell culture. 2. Magnolol increased corticosterone secretion in a dose-dependent manner, this effect being maximal at 40 microM. A similar effect was seen in a minced adrenal gland system. 3. In magnolol-treated cells, the number and total area of cytoplasmic lipid droplets were reduced, suggesting a high utilization rate of cholesterol esters stored in lipid droplets. In control cells, the capsule of the lipid droplet was clearly delineated by immunostaining with antibody A2, whereas capsular staining was discontinuous or undetectable following magnolol treatment. The percentage of decapsulated cells increased significantly from 20% in the control group to 80% in the magnolol-treated group. 4. Magnolol-induced steroidogenesis was not mediated either via the traditional ACTH-cyclic AMP-protein kinase A pathway or by protein kinase C, since the intracellular cyclic AMP level did not change and inhibition of protein kinase A or C did not block the action of magnolol. Furthermore, calcium/calmodulin-dependent protein kinase II was not involved in magnolol-induced steroidogenesis. 5. The stimulatory effect of magnolol on steroidogenesis apparently requires new protein synthesis, since cycloheximide inhibited magnolol-induced corticosterone production by 50%. 6. Although other studies have shown that high concentrations of magnolol inhibit acyl-CoA: cholesterol acyltransferase and 11 beta-hydroxysteroid dehydrogenase in a cell-free system, our data show that, in adrenal cell cultures, low concentrations of magnolol have a stimulatory effect on steroidogenesis, and the glucocorticoid produced may explain the effective control of asthma by Magnolia officinalis.

Adrenal Glands↗
PubMed2000

Preoperative anxiety and postoperative nausea and vomiting in children: is there an association?

UNLABELLED: We performed a cross-sectional study to explore a potential association between preoperative anxiety and postoperative nausea and vomiting (PONV). The study enrolled 51 unpremedicated children 5-16 yr old undergoing outpatient surgery and standardized general anesthesia. Anxiety of children was assessed in the preoperative holding area and during the induction of anesthesia. The incidence of nausea and vomiting was documented in the postanesthesia care unit (PACU) and 24 h postoperatively (POD#1). In addition to univariate analysis, we used multivariate logistic regression models, wherein the dependent variable was the presence or absence of PONV and the independent variables included potential confounders such as age, sex, and perioperative opioid consumption. Univariate analysis showed that children who experienced nausea (32 +/- 5 vs 31 +/- 4, P = ns) or vomiting (32 +/- 4 vs 32 +/- 5, P = ns) in the PACU did not differ significantly in their anxiety before surgery. A multivariate model, in which the dependent variable was the presence or absence of vomiting at POD#1 and the independent variables included preoperative anxiety, age, sex, and opioid consumption, indicated that preoperative anxiety does not predict the occurrence of nausea and vomiting (P = ns). We conclude that children's anxiety in the preoperative holding area has no predictive value for the occurrence of PONV in the PACU or POD#1. IMPLICATIONS: This study was performed to explore a possible association between children's anxiety before surgery and postoperative nausea and vomiting. We found that controlling for confounding variables, anxiety in the preoperative holding area has no predictive value for the occurrence of postoperative nausea and vomiting.

Adolescent↗
PubMed2000

Parental presence and a sedative premedicant for children undergoing surgery: a hierarchical study.

BACKGROUND: Although some anesthesiologists use oral sedatives or parental presence during induction of anesthesia (PPIA) to treat preoperative anxiety in children, others may use these interventions simultaneously (e.g., sedatives and PPIA). The purpose of this investigation was to determine whether this approach has advantages over treating children with sedatives alone. METHODS: The child's and the parental anxiety throughout the perioperative period was the primary endpoint of the study. Parental satisfaction was the secondary endpoint. Subjects (n = 103) were assigned randomly to one of two groups: a sedative group (0.5 mg/kg oral midazolam) or a sedative and PPIA group. Using standardized measures of anxiety and satisfaction, the effects of the interventions on the children and parents were assessed. Statistical analysis (varimax rotation) of the satisfaction questionnaire items resulted in two factors that described satisfaction of the separation process and satisfaction of the overall care provided. RESULTS: Anxiety in the holding area, at entrance to the operating room, and at introduction of the anesthesia mask did not differ significantly between the two groups (F[2,192] = 1.26, P = 0.28). Parental anxiety after separation, however, was significantly lower in the sedative and PPIA group (F[2,93] = 4.46, P = 0.037). Parental satisfaction with the overall care provided (-0.28 +/- 1.2 vs. 0.43 +/- 0.26, P = 0.046) and with the separation process (-0.30 +/- 1.2 vs. 0.47 +/- 0.20, P = 0.03) was significantly higher among the sedative and PPIA group compared with the sedative group. CONCLUSIONS: PPIA in addition to 0.5 mg/kg oral midazolam has no additive effects in terms of reducing a child's anxiety. Parents who accompanied their children to the operating room, however, were less anxious and more satisfied.

Adult↗
PubMed2000

Attenuation of the preoperative stress response with midazolam: effects on postoperative outcomes.

BACKGROUND: Previously, effects of preoperative sedatives were assessed mainly with respect to preoperative outcomes such as anxiety and compliance. The purpose of this investigation was to evaluate the effects of preoperative sedatives on postoperative psychological and clinical recovery. METHODS: Patients undergoing general anesthesia and outpatient surgery were enrolled in a double-blind, randomized, placebo-controlled trial. Subjects (n = 55) were randomly assigned to receive either 5 mg intramuscular midazolam (n = 26) or a placebo injection (n = 29) at least 30 min before surgery. The anesthetic technique was controlled. Postoperative anxiety, pain, analgesic consumption, clinical recovery parameters, and global health (SF-36) were evaluated up to 1 month after surgery. RESULTS: Surgery length did not differ significantly between the treatment and placebo groups (118 +/- 45 min vs 129 +/- 53 min; P = NS). Throughout the first postoperative week, subjects in the treatment group reported a greater reduction in postoperative pain compared with subjects in the placebo group (F1,50= 3.5; P = 0.035). Moreover, at 1 week, ibuprofen use was reported by less subjects in the treatment group than in the placebo group (0% vs 17.2%; P = 0.026). Subjects in the treatment group also reported a greater reduction in postoperative anxiety throughout the follow-up period (F1,53 = 9.2; P = 0.04). However, global health indexes (SF-36) did not detect any significant differences between the two experimental groups (multivariate F1,45 = 0.44; P = 0.51). CONCLUSION: Subjects treated with midazolam preoperatively self-report improved postoperative psychological and pain recovery. However, the clinical significance of these findings is unclear at the present time.

Adult↗