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Chang YY, Kim KS, Jung JH, Yang JK, Lee SM. Application of iron-coated sand and manganese-coated sand on the treatment of both As(III) and As(V). WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2007; 55:69-75. [PMID: 17305125 DOI: 10.2166/wst.2007.029] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
In this study, manganese-coated sand (MCS) and iron-coated sand (ICS) were applied in the oxidation of As(III) and adsorption of As(V), respectively. ICS and MCS were prepared by mixing FeCl3 and Mn(NO3)2, respectively, with Joomoonjin sand at 150 degrees C. In the batch adsorption isotherms, adsorption of As(III) and As(V) onto ICS followed a Langmuir type. ICS showed a greater capacity in the removal of As(V) than As(III) and also in the removal of As(V) compared with MCS. Three different configurations of ICS and MCS were used to investigate the oxidation of As(III) and adsorption of As(V) in a column. In the homogenised system, arsenic breakthrough was approximately two-times delayed compared with the separately packed systems. After breakthrough of arsenic, concentration of As(III) in the effluents was below 40 ppb for the entire reaction period in all configurations, and most arsenic was identified as As(V) owing to near complete conversion of As(III) to As(V) by MCS. The catalytic activity of MCS on the oxidation of As(III) was maintained up to 700 pore volumes, which corresponds to the treatment of at least 300 mg As(III) based on the 1 kg MCS. Compared with the homogenised column, the released Mn(II) concentration from two-staged and four-staged columns was great for the entire reaction period. In the case where the same amount of ICS and MCS was packed in a filtration system, the homogenised column was identified as a better configuration compared with the two-staged and four-staged columns when considering the arsenic breakthrough time as well as the released concentration of Fe(III) and Mn(II).
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Su CF, Chang YY, Pai HH, Liu IM, Lo CY, Cheng JT. Mediation of beta-endorphin in exercise-induced improvement in insulin resistance in obese Zucker rats. Diabetes Metab Res Rev 2005; 21:175-82. [PMID: 15386812 DOI: 10.1002/dmrr.496] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
BACKGROUND Aerobic exercise including treadmill running has long been used to successfully treat and/or prevent insulin resistance and type-2 diabetes. Increase of plasma beta-endorphin is observed with exercise. The present study was designed to clarify the role of endogenous beta-endorphin in exercise-induced improvement in insulin resistance. METHODS We used a moderate exercise program consisting of treadmill running at 20 m/min and 0% grade for 1 h/day, 7 days/week, for 8 weeks. Plasma glucose concentration was assessed by the glucose oxidase method. The enzyme-linked immunosorbent assay was performed to quantify the plasma level of beta-endorphin-like immunoreactivity (BER). The glucose disposal rate (GDR) was measured by the hyperinsulinemic euglycemic clamp technique. Changes of the insulin signaling in isolated soleus muscle were then detected by immunoprecipitation and immunoblotting. RESULTS An increase of plasma BER in parallel with the reduction of plasma glucose was obtained in exercise-trained obese Zucker rats. Different from a marked reduction in sedentary obese rats, the value of insulin-stimulated GDR obtained from the exercised obese rats was reversed to near that of the sedentary lean group, eight weeks after the last period of exercise. This effect of exercise was inhibited by naloxone or naloxonazine at doses sufficient to block opioid micro-receptors. Signaling-related defects in the soleus muscle of sedentary obese Zucker rats, which impaired glucose transporter subtype 4 (GLUT 4), included decreased phosphorylation of insulin receptor substrate (IRS)-1, as well as an attenuated p85 regulatory subunit of phosphatidylinositol 3-kinase (PI3 kinase) and Akt serine phosphorylation. In contrast, exercise training failed to modify the levels of insulin receptor (IR), IRS-1, and IR tyrosine autophosphorylation in obese Zucker rats. CONCLUSION Enhanced insulin sensitivity via exercise training might be mediated by endogenous beta-endorphin through an increase of postreceptor insulin signaling related to the IRS-1-associated PI3-kinase step that leads to the enhancement of GLUT 4 translocation and improved glucose disposal in obese Zucker rats.
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Wang SH, Sheng WH, Chang YY, Wang LH, Lin HC, Chen ML, Pan HJ, Ko WJ, Chang SC, Lin FY. Healthcare-associated outbreak due to pan-drug resistant Acinetobacter baumannii in a surgical intensive care unit. J Hosp Infect 2003; 53:97-102. [PMID: 12586567 DOI: 10.1053/jhin.2002.1348] [Citation(s) in RCA: 103] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Acinetobacter baumannii is ubiquitous and has recently become one of the most important healthcare-associated (HA) pathogens in hospitals. Infection caused by this organism often leads to significant morbidity and mortality. Outbreaks of pan-drug resistant Acinetobacter baumannii (PDRAB) have rarely been reported. During a two-month period, an outbreak of PDRAB colonization and infection affecting 7 patients occurred in our surgical intensive care unit (SICU). The colonized sites were respiratory tract (N = 7) and central venous catheter (N = 2). One of the patients had a surgical wound infection. Extensive environmental contamination was identified, including sites such as bed rails, bedside tables, surface of ventilators and infusion pump, water for nasogastric feeding and ventilator rinsing and sinks. All of the isolates were analysed by pulsed-field gel electrophoresis (PFGE) and showed an identical pattern. After use of strict cohort nursing, hand hygiene environmental cleaning, and replacement of a dysfunctional high-efficiency particulate air filter (HEPA), the outbreak was controlled.
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Chen WH, Kao YF, Lan MY, Chang YY, Liu JS. A perturbation of antithrombin-III and protein C coupling associates with an increase of anti-beta2-glycoprotein I antibody in non-antiphospholipid antibody syndrome cerebral ischemia. Blood Coagul Fibrinolysis 2002; 13:703-9. [PMID: 12441909 DOI: 10.1097/00001721-200212000-00006] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Anti-beta -glycoprotein I antibody (abetaGPI) has been recognized in raising the risk of cerebral ischemia in patients with antiphospholipid antibody syndrome (APS), especially by protein C (PC) axis perturbation. Although a high potential is also seen in non-APS patients, the mechanism is substantially unknown. In the present study, we examined the effect of abetaGPI on PC and antithrombin-III (AT-III) activity in non-APS patients with non-cardiac cerebral ischemia (NCCI). A total of 111 NCCI patients and 30 healthy controls were enrolled. They were free of APS manifestation, and their anticardiolipin antibody and lupus anticoagulant tests were within normal range. There were 14.4% patients found to have an abnormal increase of blood abetaGPI. The PC, AT-III, albumin, aminotransferases, creatinine, prothrombin time and activated partial thromboplastin time did not differ between our patients and controls, or patients with or without increased abetaGPI. However, a marked decrease of the PC/AT-III ratio was found in patients with increased abetaGPI. The correlation between PC and AT-III activity was highly significant in patients with an increase of abetaGPI (P = 0.001), only marginal in controls (P = 0.042), and was insignificant in patients with a normal abetaGPI (P = 0.277). The abetaGPI did not correlate to PC or AT-III activity in either patients or controls. These findings suggest that high PC/AT-III coupling may relate to NCCI in non-APS patients associated with an increase of abetaGPI. This coupling effect seems not to be caused by abetaGPI directly.
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Chia JS, Chang LY, Shun CT, Chang YY, Tsay YG, Chen JY. A 60-kilodalton immunodominant glycoprotein is essential for cell wall integrity and the maintenance of cell shape in Streptococcus mutans. Infect Immun 2001; 69:6987-98. [PMID: 11598074 PMCID: PMC100079 DOI: 10.1128/iai.69.11.6987-6998.2001] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2001] [Accepted: 07/12/2001] [Indexed: 11/20/2022] Open
Abstract
We have demonstrated previously by Western blotting that in naturally sensitized humans, the serum or salivary antibody response to Streptococcus mutans was directed predominantly to a protein antigen with a size of approximately 60-kDa. To identify this immunodominant antigen, specific serum antibodies were eluted from immunoblots and five positive clones with inserts ranging in length from 3 to 8 kb from identical chromosomal loci were obtained by screening a genomic expression library of Streptococcus mutans GS-5. Amino acid sequencing established the identity of this immunodominant antigen, a 60-kDa immunodominant glycoprotein (IDG-60), to be a cell wall-associated general stress protein GSP-781, which was originally predicted to have a molecular mass of approximately 45 kDa based on the derived nucleotide sequence. Discrepancy in the molecular mass was also observed in recombinant his-tagged IDG-60 (rIDG-60) expressed from Escherichia coli. Glycosylation, consisting of sialic acid, mannose galactose, and N-acetylgalactosamine, was detected by lectin binding to IDG-60 in cell wall extracts from S. mutans and rIDG-60 expressed in vivo or translated in vitro. Despite the presence of multiple Asn or Ser or Thr glycosylation sites, IDG-60 was resistant to the effect of N-glycosidase F and multiple O-glycosidase molecules but not to beta-galactosidase. Insertional inactivation of the gene encoding IDG-60, sagA, resulted in a retarded growth rate, destabilization of the cell wall, and pleiomorphic cell shape with multifold ingrowth of cell wall. In addition, distinct from the parental GS-5 strain, the isogenic mutant GS-51 was unable to survive the challenge of low pH and high osmotic pressure or high temperature. Expression of the wild-type gene in trans within GS-51 from plasmid pDL277 complemented the growth defect and restored normal cell shape. These results suggested that IDG-60 is essential for maintaining the integrity of the cell wall and the uniformity of cell shape, both of which are indispensable for bacteria survival under stress conditions.
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Lee JR, Chang YY, Hahn MJ. Development of a new epitope tag recognized by a monoclonal antibody to Rickettsia typhi. Biotechniques 2001; 31:541-5. [PMID: 11570498 DOI: 10.2144/01313st08] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The epitope recognized by a mouse monoclonal antibody (MAb) to the crystalline surface layer protein of Rickettsia typhi, SRT10, was mapped to 10 amino acid residues (SRTag TFIGAIATDT). The oligonucleotide sequence covering the epitope recognized by SRT10 was inserted into a mammalian expression vector together with multiple cloning sites. When the SRTag was fused in frame to the coding region of the NCC27/CLIC1 gene and expressed in mammalian cells, the MAb SRT10 could detect the tagged protein by immunoblotting, immunocytochemistry, and immunoprecipitation. In addition to the SRT-NCC27/CLIC1, SRT10 could detect N-terminal-tagged MEF2D and C-terminal-tagged CD4 by immunocytochemistry. We suggest that this specific recognition of the SRTag by SRT10 is generally applicable to cellular and molecular biology research that requires the expression and detection of fusion proteins.
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Lu KY, Pan SM, Lee LL, Shia LY, Chang YY. The influence of professional commitment on turnover intention. Kaohsiung J Med Sci 2001; 17:364-71. [PMID: 11593963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023] Open
Abstract
This study investigated the influence of professional commitment on turnover intentions of nurses. The study also examined the relationships between demographic data, work-related variables and the professional commitment. The self-administered questionnaires were distributed to one fifth of Southern Taiwan's population of nurses (n = 4,000). A total of 2,543 subjects completed the questionnaires with a 63.6% response rate. The nurses exhibited a medium-high degree of overall professional commitment. Age, salary, years in profession and years in organization were correlated significantly with professional commitment by Pearson's correlation. There were significant correlations between professional commitment and marital status, educational level, status of the youngest child, level of position, and family support in Spearman's correlations. Family support, age, level of position and status of hospital were the significant predictors in the final regression analysis model. The discriminant analysis showed that 45.4% of nursing professional commitment was correctly classified in predicting intention to leave the profession and 33.1% in predicting the intention to leave the organization. The study recommended that nursing professional commitment is an important moderator to affect the turnover intention of staff nurses.
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Huang CY, Fujimura M, Chang YY, Chan PH. Overexpression of copper-zinc superoxide dismutase attenuates acute activation of activator protein-1 after transient focal cerebral ischemia in mice. Stroke 2001; 32:741-7. [PMID: 11239196 DOI: 10.1161/01.str.32.3.741] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Reactive oxygen species (ROS) have been implicated in reperfusion injury after focal cerebral ischemia (FCI). ROS are known to regulate the activity of transcription factors such as activator protein-1 (AP-1), which is a dimer consisting of members of the Jun and Fos families. We investigated the role of ROS in AP-1 activity after FCI using transgenic mice that overexpressed copper-zinc superoxide dismutase (SOD1) and that had reduced infarction volume after FCI. METHODS The SOD1 transgenic mice and their wild-type littermates were subjected to middle cerebral artery occlusion and reperfusion by intraluminal suture blockade. After 60 minutes of middle cerebral artery occlusion, mice were allowed to recover for 1, 2, and 4 hours before euthanasia. Protein expression of c-Jun and c-Fos was examined by immunohistochemistry and Western blotting. AP-1 DNA-protein binding activity was assessed by electrophoretic mobility shift assays. RESULTS In wild-type mice, immunohistochemistry demonstrated acute c-Jun and c-Fos activation in ischemic cortex and its outer boundary. Expression of both was reduced in SOD1 transgenic mice. Western blotting confirmed that SOD1 overexpression was associated with reduced c-Jun and c-Fos protein levels in ischemic brain. Electrophoretic mobility shift assays revealed that the ischemia-enhanced DNA binding activity observed in wild-type mice was reduced in SOD1 transgenic mice. Supershift assays indicated that c-Jun participated in the bound AP-1 complex. CONCLUSIONS SOD1 overexpression prevents early activation of AP-1 after transient FCI in mice. This may block the expression of downstream target genes that are injurious, thereby reducing the infarction volume after transient FCI in mice.
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Huang YT, Lin HC, Chang YY, Yang YY, Lee SD, Hong CY. Hemodynamic effects of synephrine treatment in portal hypertensive rats. JAPANESE JOURNAL OF PHARMACOLOGY 2001; 85:183-8. [PMID: 11286401 DOI: 10.1254/jjp.85.183] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Synephrine, a sympathomimetic alpha1-adrenoceptor agonist, has been shown to induce dose-dependent portal hypotensive effects after acute intravenous infusion. The present study was undertaken to investigate the hemodynamic effects of 8-day administration of synephrine in portal hypertensive rats. Portal hypertension was induced by either partial portal vein ligation (PVL) or bile duct ligation (BDL). Portal hypertensive rats were allocated into one of two groups: vehicle group (0.1 N HCl, 0.5 ml/12 h) or synephrine group (1 mg/kg per 12 h), with 7 rats in each group. Synephrine or vehicle was administered by gavage into PVL and BDL rats for 8 consecutive days. Systemic as well as splanchnic hemodynamic parameters were measured thereafter. Synephrine significantly ameliorated the hyperdynamic state in both PVL and BDL rats. The portal venous pressure in PVL and BDL rats (-13.5% and -10.1%, respectively), portal tributary blood flow (-19.5% and -20.4%) and cardiac index (-12.1% and -18.8%) were significantly reduced, while mean arterial pressure (10.4% and 23.4%) and systemic (26.3% and 51.0%) as well as portal territory (47.1% and 67.7%) vascular resistance were enhanced by treatment of synephrine as compared with vehicle treatment. Our results showed that eight-day administration of synephrine exerted beneficial hemodynamic effects in two models of portal hypertensive rats.
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Wang JT, Chang SC, Ko WJ, Chang YY, Chen ML, Pan HJ, Luh KT. A hospital-acquired outbreak of methicillin-resistant Staphylococcus aureus infection initiated by a surgeon carrier. J Hosp Infect 2001; 47:104-9. [PMID: 11170773 DOI: 10.1053/jhin.2000.0878] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) has become an important hospital-acquired pathogen, infection with which often leads to major morbidity and mortality. The principal mode of transmission for MRSA is transfer of the organism from a carrier or infected patient to uninfected patients by the hands or clothing of staff. From January 16 1997 to April 2 1997, five patients who had undergone open-heart surgery in a hospital located in northern Taiwan, developed surgical wound infections and mediastinitis caused by MRSA. All patients were hospitalized in two adjacent surgical intensive care units (ICUs) following their respective operations. Consequently, the hospital's infection control team commenced investigation of the outbreak. Pulsed-field gel electrophoresis (PFGE) has been shown to be a good technique for epidemiological typing. By analysing cultures taken from staff by PFGE, it was demonstrated that this outbreak was most likely to be initiated by a surgeon with MRSA carriage. After elimination of the carrier state using topical mupirocin treatment, the outbreak was controlled without further incident.
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Choe S, Lee SH, Chang YY, Hwang KY, Khim J. Rapid reductive destruction of hazardous organic compounds by nanoscale Fe0. CHEMOSPHERE 2001; 42:367-372. [PMID: 11100787 DOI: 10.1016/s0045-6535(00)00147-8] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Fe0-mediated reductive destruction of hazardous organic compounds such as chlorinated organic compounds (COCs) and nitroaromatic compounds (NACs) in the aqueous phase is one of the latest innovative technologies. In this paper, rapid reductive degradation of COCs and NACs by synthesized nanoscale Fe0 in anaerobic batch systems was presented. The nanoscale Fe0, characterized by high specific surface area and high reactivity, rapidly transformed trichloroethylene (TCE), chloroform (CF), nitrobenzene (NB), nitrotoluene (NT), dinitrobenzene (DNB) and dinitrotoluene (DNT) under ambient conditions, which results in complete disappearance of the parent compounds from the aqueous phase within a few minutes. GC analysis reported that the main products of the dechlorination of TCE and CF were ethane and methane as well as that most of the nitro groups in NACs were reductively transformed to amine groups. These results suggest that the rapid reductive destruction by nanoscale Fe0 is potentially a viable in situ or aboveground treatment of groundwater contaminated with hazardous organic compounds including COCs and NACs.
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Lu KY, Chang YY, Chiou SL. [Changes in nursing professional commitment among junior college graduates]. HU LI YAN JIU = NURSING RESEARCH 2001; 9:28-38. [PMID: 11548213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
The purposes of this longitudinal study were to understand the changes in professional commitment from nursing students before graduation to registered nurses one year and two years after their graduation, and to find the relationship among these changes, work backgrounds and organizational satisfaction. The sample consisted of 890 junior college graduates. The Nursing Professional Commitment Scale was used for data collection at the first and the second test, while work backgrounds and organizational satisfaction were included at the third test. The data were analyzed by using percentage, mean, standard deviation, correlation and repeated measure ANOVA statistical methods. The results showed that: (1) The average scores of the three tests were 2.96, 2.84 and 2.79, with a full point scale of 4. (2) There were positive correlations among the three tests of professional commitments; also, positive correlation was shown between organizational satisfaction and professional commitment on the third test. (3) The scores for overall nursing professional commitment decreased significantly one year after graduation, but there was no significant changes from one year to two years after graduation. (4) There was a significant relationship between the changes in professional commitment and grades of hospital, but no significant relationship with job category or work unit. (5) Organizational satisfaction influenced the decrease in professional commitment from nursing students before graduation to two years after graduation; it also changed professional commitment from one to two years after graduation significantly. The author suggests that nursing educators and administrators should be concerned with changes in the professional commitment of nurses so as to increase nurses' organizational satisfaction.
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Huang CY, Fujimura M, Noshita N, Chang YY, Chan PH. SOD1 down-regulates NF-kappaB and c-Myc expression in mice after transient focal cerebral ischemia. J Cereb Blood Flow Metab 2001; 21:163-73. [PMID: 11176282 DOI: 10.1097/00004647-200102000-00008] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Reactive oxygen species (ROS) are implicated in reperfusion injury after focal cerebral ischemia (FCI). Reactive oxygen species regulate activity of transcription factors like NF-kappaB. The authors investigated the role of ROS in NF-kappaB activity after FCI using transgenic mice that overexpressed human copper/zinc-superoxide dismutase (SOD1) and that had reduced infarction volume after FCI. Superoxide dismutase transgenic and wild-type mice were subjected to 1 hour of middle cerebral artery occlusion (MCAO) and subsequent reperfusion. Immunohistochemistry showed SOD1 overexpression attenuated ischemia-induced NF-kappaB p65 immunoreactivity. Colocalization of NF-kappaB and the neuronal marker, microtubule-associated proteins (MAPs), showed that NF-kappaB was up-regulated in neurons after FCI. Electrophoretic mobility shift assays showed that SODI overexpression reduced ischemia-induced NF-kappaB DNA binding activity. Supershift assays showed that DNA-protein complexes contained p65 and p50 subunits. Immunoreactivity of c-myc, an NF-kappaB downstream gene, was increased in the ischemic cortex and colocalized with NF-kappaB. Western blotting showed that SOD1 overexpression reduced NF-kappaB and c-Myc protein levels in the ischemic brain. Colocalization of c-Myc and TUNEL staining was observed 24 hours after FCI. The current findings provide the first evidence that SOD1 overexpression attenuates activation of NF-kappaB after transient FCI in mice and that preventing this early activation may block expression of downstream deleterious genes like c-myc, thereby reducing ischemic damage.
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Chang YY, Cronan JE. Conversion of Escherichia coli pyruvate oxidase to an 'alpha-ketobutyrate oxidase'. Biochem J 2000; 352 Pt 3:717-24. [PMID: 11104678 PMCID: PMC1221509] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Escherichia coli pyruvate oxidase (PoxB), a lipid-activated homotetrameric enzyme, is active on both pyruvate and 2-oxobutanoate ('alpha-ketobutyrate'), although pyruvate is the favoured substrate. By localized random mutagenesis of residues chosen on the basis of a modelled active site, we obtained several PoxB enzymes that had a markedly decreased activity with the natural substrate, pyruvate, but retained full activity with 2-oxobutanoate. In each of these mutant proteins Val-380 had been replaced with a smaller residue, namely alanine, glycine or serine. One of these, PoxB V380A/L253F, was shown to lack detectable pyruvate oxidase activity in vivo; this protein was purified, studied and found to have a 6-fold increase in K(m) for pyruvate and a 10-fold lower V(max) with this substrate. In contrast, the mutant had essentially normal kinetic constants with 2-oxobutanoate. The altered substrate specificity was reflected in a decreased rate of pyruvate binding to the latent conformer of the mutant protein owing to the V380A mutation. The L253F mutation alone had no effect on PoxB activity, although it increased the activity of proteins carrying substitutions at residue 380, as it did that of the wild-type protein. The properties of the V380A/L253F protein provide new insights into the mode of substrate binding and the unusual activation properties of this enzyme.
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Hwang SL, Yang YH, Lieu AS, Chuang MC, Chang SJ, Chang YY, Lin HJ, Howng SL. The conditional survival statistics for survivors with primary supratentorial astrocytic tumors. J Neurooncol 2000; 50:257-64. [PMID: 11263506 DOI: 10.1023/a:1006484220764] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
BACKGROUND Relative survival rates can offer a general description of tumor outcome and, traditionally, are used for surveillance and comparison purposes. However, they are not informative for individual tumor survivors. Conditional survival estimates can calculate the probability of surviving next some years given survival to a specific period of time after craniotomy for individual tumor survivors. However, clinically, they have not been used for predicting the tumor outcome. METHODS We calculated conditional probabilities of survival within 6 years after craniotomy in 112 patients with primary supratentorial astrocytic tumors and evaluated factors affecting the survival time more than 2 years after craniotomy. RESULTS Our data showed that the conditional probability of survival can predict yearly survival rate when patients survive for a specific period of time. The conditional survival rates within 6 years after craniotomy were always higher than those evaluated by relative survival rates. Overall, the longer the patients survived, the higher the conditional probabilities of surviving sixth year postoperatively were. CONCLUSION Our study demonstrates the conditional probabilities of survival have good availability and are important estimates for individual tumor survivors.
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Choe S, Chang YY, Hwang KY, Khim J. Kinetics of reductive denitrification by nanoscale zero-valent iron. CHEMOSPHERE 2000; 41:1307-1311. [PMID: 10901263 DOI: 10.1016/s0045-6535(99)00506-8] [Citation(s) in RCA: 153] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Zero-valent iron powder (Fe0) has been determined to be potentially useful for the removal of nitrate in the water environment. This research is aimed at subjecting the kinetics of denitrification by nanoscale Fe0 to an analysis of factors affecting the chemical denitrification of nitrate. Nanoscale iron particles with a diameter in the range of 1-100 nm, which are characterized by the large BET specific surface area to mass ratio (31.4 m2/g), removed mostly 50, 100, 200, and 400 mg/l of nitrate within a period of 30 min with little intermediates. Compared with microscale (75-150 microm) Fe0, end product is not ammonia but N2 gas. Kinetics analysis from batch studies revealed that the denitrification reaction with nanoscale Fe0 appeared to be a pseudo first-order with respect to substrate and the observed reaction rate constant (k(obs)) varied with iron content at a relatively low degree of application. The effects of mixing intensity (rpm) on the denitrification rate suggest that the denitrification appears to be coupled with oxidative dissolution of iron through a largely mass transport-limited surface reaction (<40 rpm).
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Shu BC, Tien AY, Lung FW, Chang YY. Norms for the Wisconsin Card Sorting Test in 6- to 11-year-old children in Taiwan. Clin Neuropsychol 2000; 14:275-86. [PMID: 11262702 DOI: 10.1076/1385-4046(200008)14:3;1-p;ft275] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The main aims of this study were to develop norms for the Wisconsin Card Sorting Test in 6- to 11-year-old children in Taiwan; to explore the effect of sex, age, birth order, number of siblings, and parental education on WCST performance in 6- to 11-year-old children; and to make a comparison of WCST performance between children in Taiwan and the USA. The results of this comparison of developmental norms of school children in Taiwan and the United States may facilitate the WCST as a clinical or research instrument in combination with other test procedures to assess aspects of cognitive and neuropsychological functioning of school children.
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Chang YY, Eichel J, Cronan JE. Metabolic instability of Escherichia coli cyclopropane fatty acid synthase is due to RpoH-dependent proteolysis. J Bacteriol 2000; 182:4288-94. [PMID: 10894739 PMCID: PMC101943 DOI: 10.1128/jb.182.15.4288-4294.2000] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cyclopropane fatty acids (CFAs) are generally synthesized as bacterial cultures enter stationary phase. In Escherichia coli, the onset of CFA synthesis results from increased transcription of cfa, the gene encoding CFA synthase. However, the increased level of CFA synthase activity is transient; the activity quickly declines to the basal level. We report that the loss of CFA activity is due to proteolytic degradation dependent on expression of the heat shock regulon. CFA synthase degradation is unaffected by mutations in the lon, clpP, and groEL genes or by depletion of the intracellular ATP pools. It seems likely that CFA synthase is the target of an unidentified energy-independent heat shock regulon protease. This seems to be the first example of heat shock-dependent degradation of a normal biosynthetic enzyme.
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Hou MF, Tsai KB, Fan HM, Wang CY, Lin WC, Liu CS, Lin HJ, Chai CY, Fu OY, Li SS, Chang YY, Huang TJ. Familial breast cancer in southern Taiwan. Kaohsiung J Med Sci 2000; 16:414-21. [PMID: 11221545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023] Open
Abstract
The purpose of this study is to evaluate whether there are pathobiologic differences and differences in overall rates survival between familial and non-familial breast cancer patients in Taiwan. A retrospective study was performed evaluating 76 familial breast cancer patients in 69 families, which included two BRCA1 related cases and six BRCA2 related cases. Patients were compared with 425 non-familial sporadic cases. Familial breast cancer patients had similar ages and stages as non-familial patients (mean, 46.6 years vs 48.9 years, p = 0.306). However, the familial breast cancer patients with BRCA1 and BRCA2 related cases presented at lower stages (p = 0.034) and younger ages than non-familial patients (mean, 45.1 years vs 48.9 years P = 0.042). The occurrence of infiltrating ductal carcinoma and lobular carcinoma in situ was not significantly different in the two groups. Mucinous carcinoma was represented with 6.7% (4/76) and 1.3% (1/76) medullary carcinoma. The overall grade of familial breast cancer, including BRCA1 and BRCA2 related cases in 8 infiltrating ductal carcinoma, was significantly higher than that of controls. The mean follow up was 4.5 years for familial breast cancers. Five- and 10-year overall survival rates were 69% and 61% for those with a family history, compared with 86% and 64% for those in the control group (p = 0.644). There were no statistically significant differences in disease-free survival rates between the two groups at 5 or 10 years (69% vs 78% in 5 years; 48% vs 58% in 10 years) (p = 0.862). Despite the younger ages and earlier stages at presentation in familial breast cancer patients with BRCA1 and BRCA2 related cases, the familial breast cancer patients had higher grade patholobiologic characteristics, but similar prognoses when compared with sporadic breast cancer patients. Owing to the limited number of familial cases in this study, more cases and longer follow up are needed.
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Shu BC, Lung FW, Chang YY. The mental health in mothers with autistic children: a case-control study in southern Taiwan. Kaohsiung J Med Sci 2000; 16:308-14. [PMID: 11584432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023] Open
Abstract
The aim of this study was to investigate the impact of autistic children on the mental health of their mothers. Autism is a complicated neuropsychiatric disorder. Evidence shows that mothers with autistic children experience greater stress than those having children with other chronic diseases. In this study we have 1) assessed the mental health of mothers with autistic children; 2) determined their prevalence of minor psychiatric morbidity (MPM); 3) classified their MPM; and 4) determined factors related to their mental health. A case-controlled design was used to compare the mental status among mothers having children with either autistic (n = 30), or Down syndrome (n = 11) and with normal children (n = 56). The mean score of the Chinese Health Questionnaire (CHQ) showed no differences between those mothers of case and control groups. Using a 9-point criterion to screen for MPM in the CHQ, more mothers (37%) in the case group had scores > or = 9 compared with the control group (18%). Mothers of the case group had significantly higher for MPM using logistic regression analysis. The educational level was inversely related to the CHQ scores. Mothers with a CHQ score > or = 9, were later diagnosed with either depression (36%) and anxiety (46%); or anxiety and depression (9%). A primary care model for mothers with autistic children should therefore be developed to prevent them from developing mental disorders.
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Wu WT, Wang PM, Chang YY, Huang TK, Chien YH. Suspended rice particles for cultivation of Monascus purpureus in a tower-type bioreactor. Appl Microbiol Biotechnol 2000; 53:542-4. [PMID: 10855713 DOI: 10.1007/s002530051654] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cultivation of Monascus purpureus (CCRC 31615) for the production of natural pigments was investigated. Traditionally, Monascus species were grown on rice by solid-state culture. For large-scale cultivation, solid-state cultures were associated with some problems such as contamination and scale-up. By using submerged cultures with rice particles, a stirred-tank fermentor was not suitable for submerged cultures as the impeller tended to break the particles into small pieces. A conventional bubble column was also unsuitable as its mixing capability was poor. In the present study, a modified bubble column with wire-mesh draft tubes was employed for the cultivation of M. purpureus. The proposed column had a shorter mixing time and a higher oxygen transfer rate relative to the conventional bubble column. The production of pigments using the proposed column was up to 80% higher than that achieved using the conventional bubble column.
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Wu HS, Kolonoski P, Chang YY, Bermudez LE. Invasion of the brain and chronic central nervous system infection after systemic Mycobacterium avium complex infection in mice. Infect Immun 2000; 68:2979-84. [PMID: 10768998 PMCID: PMC97513 DOI: 10.1128/iai.68.5.2979-2984.2000] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/1999] [Accepted: 01/18/2000] [Indexed: 11/20/2022] Open
Abstract
Central nervous system (CNS) infections caused by nontuberculous mycobacteria have been described previously, especially in patients with AIDS. To investigate specific aspects of the pathogenesis of this entity, C57BL bg(+)/bg(-) mice were infected intravenously with Mycobacterium avium, and cultures of blood and brain as well as histopathology examination of brain tissue were carried out at several time points up to 6 months after infection. Low-grade inflammatory changes with small aggregates of lymphocytes and macrophages as well as perivascular cuffing were seen early in the infection. A small number of bacteria could be observed in the parenchyma of the choroid plexus. Six months after infection, numerous bacteria were present within the foamy macrophage of the granulomatous lesions along the ventricle and meninges. None of the mice developed clinical signs of meningitis or encephalitis or even died spontaneously during the period of observation. Use of CD18(-/-) knockout mice indicated that transport of the bacterium within neutrophils or monocytes into the brain is unlikely. Mild chronic CNS infection developed in the mice during sustained systemic M. avium infection, similar to what has been reported in most human cases.
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Liu JS, Chang YY, Wu HS, Huang CY, Chen WH, Lan MY, Kao YF, Chen SS. Transtentorial cerebellar c-jun expression after focal cerebral cortical injury in mice. Neurosci Lett 2000; 282:85-8. [PMID: 10713402 DOI: 10.1016/s0304-3940(00)00865-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Delayed and remote effect of focal cerebral cortical lesion on cerebellum remains unclear. The c-Jun, an inducible transcription factor of cellular immediate early gene, is the predominant transcription factor and consistent marker for neurons that respond to stress or injury. We use a mouse cryogenic injury model to study the spatial and temporal changes of c-jun in the cerebellum after focal neocortical lesion. A transient and moderate expression of c-jun mRNA was found in the cerebellum with central dominance since 3 day postinjury and gradually subsided within 2 weeks. A distinct increment of c-Jun protein expression in Purkinje cells of the bilateral cerebellar hemispheres with focal connotation in the vermis was detected since 1 week postinjury. These findings suggest that the delayed and remote c-jun expression of the cerebellum, functionally connected with the cerebral cortex, indicate transneuronal gene activation.
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Chen WH, Lan MY, Chang YY, Liu JS. An abnormal cholesterol profile in young adults with normocholesterolemic cerebral ischemia. Kaohsiung J Med Sci 2000; 16:141-7. [PMID: 10846350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
Abstract
An abnormal cholesterol fraction can still be able to provoke cascades of lipidic atherogenesis even when the serum TC level is within normal range (< 200 mg%). However, there is a shortage of convincing data concerning cerebral atherogenesis in young Asians who have a different diet habit and living style from those in western countries. In this study, we examined the lipoprotein-cholesterol profile in young Taiwanese patients with noncardiac cerebral ischemia (NCCI) whose serum TC level was < 200 mg% and 200-250 mg%. The results showed a decrease of HDLC and an increase of VLDLC in patients with TC < 200 mg%, but only a decrease of HDLC in patients with TC = 200-250 mg%. The cholesterol fraction metabolism is obviously perplexed in NCCI subjects. These findings were not related to their associated risk factors. Accordingly, a derangement of cholesterol fraction with normal serum TC level can also incite lipidic cerebral atherogenesis in young Taiwanese adults. Therefore, a detailed evaluation of cholesterol profile should be born in mind in young eastern NCCI patients despite of a normal serum TC level. Tailored measure of diet and living should be modified to prevent lipidic atherogenesis in our society in future.
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Lu KY, Chiou SL, Chang YY. A study of the professional commitment changes from nursing students to registered nurses. Kaohsiung J Med Sci 2000; 16:39-46. [PMID: 10741015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
Abstract
The purposes of this longitudinal study were to understand the professional commitment changes from nursing students to registered nurses. A total of 890 subjects completed the questionnaires of the nursing professional commitment and personality test before their graduation, and nursing professional commitment one year after their graduation, respectively. The data were analyzed by mean, correlation, t-test and repeated measures ANOVA. The results showed that: (1) the nurses exhibited a medium-high degree of professional commitment--the average score was 2.99 before graduation and 2.85 after graduation; (2) there was a highly significant correlation between professional commitments for nursing students and registered nurses; (3) The scores of overall commitment and four factors of professional commitment decreased from nursing students to registered nurses significantly; (4) personality traits were positively correlated with professional commitment for nursing students and registered nurses; and (5) there was no significant relationship between nurses' work backgrounds and the changes of professional commitment from nursing students to registered nurses. Implications for nursing education and for hospital management are suggested.
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