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C-H Huang

Publications and source records attributed to C-H Huang.

16 recordsLinked to original sources

Diagnostic accuracy of tissue Doppler echocardiography for patients with acute heart failure.

BACKGROUND: Acute heart failure leads to high mortality and morbidity rates. The symptom of acute dyspnoea is non-specific and the diagnostic tools of acute heart failure are still not satisfactory. Tissue Doppler echocardiography is accurate in evaluating cardiac function; however, its efficacy in diagnosing patients with acute dyspnoea in emergency departments remains unclear. METHODS: Patients with acute dyspnoea were included prospectively while visiting the emergency department. Tissue Doppler echocardiography was carried out and the ratios of peak early diastolic transmitral blood flow velocity (E) to the peak early diastolic tissue velocity over mitral annulus (Ea) were recorded. The sensitivity, specificity and accuracy of tissue Doppler parameters and the receiver-operating characteristic curves for diagnosing acute heart failure were also evaluated. RESULTS: A total of 92 patients were enrolled. The ratio E:Ea was found to be a good diagnostic test to estimate the diagnostic performances of tissue Doppler echocardiography using receiver-operating characteristic curves in cases of acute heart failure in patients with preserved left ventricular systolic function (mean (SD) area under the curve = 0.875 (0.049); p<0.001; cut-off value = 11) and with left ventricular systolic dysfunction (mean (SD) area under the curve = 0.903 (0.061); p = 0.003; cut-off value = 16). E:Ea was an independent predictor of acute heart failure in multiple logistic regressions. For patients with a B-type natriuretic peptide level between 100 and 500 pg/ml, E:Ea provided an accuracy of 90.9% (p = 0.015) for diagnosing acute heart failure. CONCLUSIONS: Tissue Doppler echocardiography is accurate in diagnosing patients with acute heart failure in emergency departments. It can be a useful supplementary diagnostic tool for patients with inconclusive blood B-type natriuretic peptide level.

Acute Disease↗

Calciphylaxis.

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Aged↗

A randomised double-blind controlled study evaluating the hypothermic effect of 150 microg morphine during spinal anaesthesia for Caesarean section.

We studied the hypothermic effect of adding 150 microg morphine during spinal anaesthesia in 60 parturients scheduled for elective caesarean section. All the parturients received intrathecal injection of a solution containing 150 mug morphine or normal saline in addition to 10-12 mg hyperbaric bupivacaine 0.5%. In both groups, a significant decrease in body temperature was noted. There was no difference in the area under the curve for temperature against time for the two groups; however, the maximum decrease in temperature from baseline was significantly larger after morphine than after saline injection (mean (SD) 1.11 (0.61) degrees C vs 0.76 (0.39) degrees C, respectively; p = 0.01) and the time to nadir temperature was significantly longer (59.5 (17.6) min vs 50.4 (15.9) min, respectively; p = 0.047). The lowest temperature observed in the morphine group was 34.3 degrees C. We conclude that intrathecal injection of 150 microg morphine intensified the intra-operative hypothermic effect of bupivacaine spinal anaesthesia for caesarean section.

Adult↗

Transvascular dissemination of Porphyromonas gingivalis from a sequestered site is dependent upon activation of the kallikrein/kinin pathway.

BACKGROUND AND OBJECTIVE: Epidemiological evidence implicates a connection between human periodontitis and systemic diseases. One possible mechanism involves the direct dissemination of periodontopathogens to the target organs through the circulation. The aim of this work was to define the mechanism used by Porphyromonas gingivalis for dissemination from a sequestered infection site. MATERIAL AND METHODS: BALB/c mice were subcutaneously infected with P. gingivalis via use of a mouse chamber model. Tissue fluids from various sites were collected and cultured to determine the presence of P. gingivalis. Evans Blue dye was used to measure the dissemination ability of P. gingivalis. Kinin-associated molecules were introduced into mice, and their effects on bacterial dissemination and mouse pathology were monitored. RESULTS: P. gingivalis strain A7436 caused remote lesions and septicemia with severe cachexia, resulting in animal death. Intrachamber challenge with A7436 resulted in vascular permeability enhancement (VPE), as measured by the systemic infiltration of Evans Blue dye into chamber fluids. VPE was blocked by kininase and kinin receptor antagonist and enhanced by exogenous bradykinin and kininase inhibitor. Live bacteria were recovered from the subcutaneous perichamber and abdominal spaces (spreading), and from the blood (disseminating) of infected mice. Both kininase and kinin receptor antagonist reduced animal mortality as a result of infection with strain A7436 and decreased the number of bacteria recoverable from the blood, but they were not associated with bacterial spreading. CONCLUSIONS: The results suggest that activation of the kinin system is involved in the breach of the vascular barrier that permits dissemination of P. gingivalis.

Angiotensin-Converting Enzyme Inhibitors↗

Identification and molecular characterization of Zantedeschia mild mosaic virus, a new calla lily-infecting potyvirus.

Tissue-cultured seedlings of calla lily (Zantedeschia spp.) with mild mosaic symptom were observed in Taiwan. A new potyvirus, Zantedeschia mild mosaic virus (ZaMMV), was identified in the diseased plants based on the result of ELISA, virion morphology and sequence data. In the host range test, ZaMMV only infected Philodendron selloum and Zantedeschia spp. causing systemic mosaic and mild mosaic symptom, respectively. The 3'-terminal region of the virus was amplified by RT-PCR from total RNA using a potyvirus-specific degenerate primer and an oligo-dT primer. Sequence analysis revealed that the highest amino acid sequence identity of the capsid protein (CP) gene between ZaMMV and thirty potyviruses was 55%, and the highest nucleotide identity of 3' untranslated region (3'UTR) was 52%. Therefore, in terms of species demarcating criteria, ZaMMV is a new species of the genus Potyvirus. From the result of phylogenetic analysis, ZaMMV should be a member of the Bean common mosaic virus subgroup. According to the deduced amino acid sequence of ZaMMV, the N terminus of the CP contained 39 glutamine residues before DAG motif. This unique sequence has never been discovered in plant viruses.

Amino Acid Sequence↗

Cancer immunotherapy using a DNA vaccine encoding a single-chain trimer of MHC class I linked to an HPV-16 E6 immunodominant CTL epitope.

The potency of DNA vaccines may be affected by the efficiency of intracellular processing and MHC class I presentation of encoded antigens. Since a single-chain trimer (SCT) composed of peptide, beta2-microglobulin (beta2m), and MHC class I heavy chain has been shown to bypass antigen processing and lead to stable presentation of peptides, we investigated the efficacy of a DNA vaccine encoding a SCT composed of an immunodominant CTL epitope of human papillomavirus type 16 (HPV-16) E6 antigen, beta2m, and H-2Kb MHC class I heavy chain (pIRES-E6-beta2m-Kb). Transfection of 293 cells with pIRES-E6-beta2m-Kb can bypass antigen processing and lead to stable presentation of E6 peptide. Furthermore, C57BL/6 mice vaccinated with pIRES-E6-beta2m-Kb exhibited significantly increased E6 peptide-specific CD8+ T-cell immune responses compared to mice vaccinated with DNA encoding wild-type E6. Most importantly, 100% of mice vaccinated with pIRES-E6-beta2m-Kb DNA were protected against a lethal challenge of E6-expressing TC-1 tumor cells. In contrast, all mice vaccinated with wild-type E6 DNA or control plasmid DNA grew tumors. Our data indicate that a DNA vaccine encoding a SCT can lead to stable enhanced MHC class I presentation of encoded antigenic peptide and may be useful for improving DNA vaccine potency to control tumors or infectious diseases.

Animals↗

Exact algorithms for planted motif problems.

The problem of identifying meaningful patterns (i.e., motifs) from biological data has been studied extensively due to its paramount importance. Three versions of this problem have been identified in the literature. One of these three problems is the planted (l, d)-motif problem. Several instances of this problem have been posed as a challenge. Numerous algorithms have been proposed in the literature that address this challenge. Many of these algorithms fall under the category of heuristic algorithms. In this paper we present algorithms for the planted (l, d)-motif problem that always find the correct answer(s). Our algorithms are very simple and are based on some ideas that are fundamentally different from the ones employed in the literature. We believe that the techniques we introduce in this paper will find independent applications.

Algorithms↗

NF-kappaB inhibitors stabilize the mRNA of high-affinity type-2 cationic amino acid transporter in LPS-stimulated rat liver.

BACKGROUND: Induction of inducible nitric oxide synthase (iNOS) results in nitric oxide (NO) overproduction during endotoxemia. Cellular uptake of L-arginine, modulated by the isozymes of type-2 cationic amino acid transporters (CAT), including CAT-2, CAT-2A and CAT-2B, has been reported to be a crucial factor in the regulation of iNOS activity. We sought to elucidate the expression of CAT-2 isozymes and the role of nuclear factor-kappaB (NF-kappaB) in this expression in lipopolysaccharide (LPS)-treated rat liver. METHODS: Adult male Sprague-Dawley rats were randomly given intravenous (i.v.) injections of normal saline (N/S), LPS, LPS preceded by an NF-kappaB inhibitor (PDTC, dexamethasone or salicylate) or an NF-kappaB inhibitor alone. After injection, rats were sacrificed at different times and enzyme expression and liver injury were examined. Hepatic and systemic NO production were also measured. RESULTS: CAT-2, CAT-2A and CAT-2B were constitutively expressed in un-stimulated rat liver. LPS stimulation not only significantly increased iNOS mRNA and NO concentrations but also decreased the mRNA concentrations of CAT-2 and CAT-2B, but not CAT-2A, in a time-dependent manner. LPS-induced hepatic and systemic NO overproduction was associated with hepatocellular injury. Pre-treatment with NF-kappaB inhibitors significantly attenuated LPS-induced iNOS induction as well as CAT-2/CAT-2B mRNA destabilization, which was associated with significant inhibition of NO biosynthesis and less liver injury. CONCLUSION: NF-kappaB inhibitors stabilize CAT-2 and CAT-2B mRNA in LPS-stimulated rat liver. The hepatic CAT-2/CAT-2B pathway may be a constitutive part of cytoprotective mechanisms against sepsis.

Alanine Transaminase↗

Severe acute respiratory syndrome in Taiwan: analysis of epidemiological characteristics in 29 cases.

OBJECTIVES: To describe the clinical characteristics and outcomes of patients with severe acute respiratory syndrome (SARS). METHODS: Between March 28 and June 30 '2003, 29 patients with probable SARS seen at Shin Kong Wu Ho-Su Memorial Hospital, Taipei, were analysed. RESULTS: Presenting symptoms included fever (100%), cough (69.0%), chills or rigor (62.1%), and shortness of breath (41.4%). Mean days to defervescence were 6.8+/-2.9 days, but fever recurred in 15 patients (51.7%) at 10.9+/-3.4 days. Common laboratory features included lymphopenia (72.4%), thrombocytopenia (34.5%) and elevated C-reactive protein (CRP), lactate dehydrogenase (LDH), and aspartate aminotransferase (AST) (93.1, 62.1, 44.8%, respectively). All patients except one had initial abnormal chest radiographs and 20 (69.0%) had radiological worsening at 7.5+/-2.6 days. Nine patients (31.0%) subsequently required mechanical ventilation with four deaths (13.8%). Most patients with clinical deterioration responded to pulse corticosteroid therapy (14 out of 17) but six complicated with nosocomial infections. The risk factors associated with severe disease were presence of diarrhoea, high peak LDH and CRP, high AST and creatine kinase on admission and high peak values. CONCLUSIONS: Prudent corticosteroid use, vigilant microbiological surveillance and appropriate antibiotics coverage are the key to successful treatment.

Adrenal Cortex Hormones↗

Deletion of arginine codon 229 in the Rhce gene alters e and f but not c antigen expression.

BACKGROUND: Rh CcEe antigens occur as ce, Ce, cE, or CE alleles in the RBC membrane. Their epitope structures and the location of their cis interacting products remain to be defined. MATERIALS AND METHODS: A rare blood sample from a white male whose parents are first cousins was identified. Hemagglutination was performed using standard methods. RH structure and genotype was assessed by Southern blots. Rh transcripts were obtained by gene-specific RT-PCR and sequenced. The mutation was verified by genomic PCR assays. RESULTS: The donor's RBCs typed D+C-c+E-e-f(Rh6)- with a normal c dose, suggesting the Dc- phenotype. Further tests revealed a weak and qualitatively altered e expression. Southern blots indicated a genotype of Dce/dce without other gross changes. RT-PCR detected a triplet deletion (Delta685AGA687) in the Rhce gene that specifies codon 229 for arginine (Arg229). Sequencing of the region around the mutated exon 5 confirmed the donor to be homozygous for the AGA deletion. DISCUSSION: Arg229 is invariant on external loop 4 and close to the Ala226Pro change specific for e/E polymorphism. The qualitative and quantitative alteration of e antigen defines Arg229 as a crucial component for e/E epitope presentation. Given a normal dose of c antigen, the disruption of f (Rh6) by Arg229 deletion suggests that external loop 4 is a major structural element contributing to the expression of RHCE cis interacting antigenic products.

Amino Acid Sequence↗

RH locus contraction in a novel Dc-/D-- genotype resulting from separate genetic recombination events.

BACKGROUND: The rare phenotypes Dc- and D-- lack the expression of E/e and CcEe antigens, respectively; their cotransmission in a single family has not been reported. STUDY DESIGN AND METHODS: Six members of a Chinese family with two exhibiting the Dc- phenotype were studied using standard serologic methods. Rh genotypes were analyzed by Southern blot, and RH loci, by exon PCR. Rh transcripts were characterized by gene-specific RT-PCR and sequencing. RESULTS: Although Rh typing detected two members as Dc- homozygotes, RFLP analysis and exon PCR showed them to be Dc- heterozygotes with a partial deletion of RHCE. cDNA sequencing showed the expression in the family of normal RHD and RHCe as well as hybrid transcripts, RHD(1-9)/RHCE(10) and RHCE(1-3)/RHD(4-10). Thus, the Dc- members had the genotype of Dc-/ D-- and expressed both hybrid genes that were inherited from their parents, respectively. DISCUSSION: This is the first demonstration in a family that the Dc- and D-- complexes neither are linked with a normal RHD or RHCE gene. The segregation of these two different hybrid genes with single break points suggests their independent genetic origin and provides molecular insights into the dynamic nature of genomic rearrangements leading to RH locus contraction.

Adult↗

Dynamic changes of gene expression profiles during postnatal development of the heart in mice.

OBJECTIVE: To study postnatal cardiac differentiation in the mouse. HYPOTHESIS: There might be mechanisms or factors in cardiac differentiation that could be identified by systematic gene expression analysis during postnatal cardiac development. METHODS: Expression of 6144 genes was examined in mouse heart, from the newborn period (day 0), through day 7 and day 14 day, to adulthood, using the cDNA microarray approach. Northern blotting and immunohistochemical techniques were used to confirm the microarray results. RESULTS: Various cardiac development related genes involving the cell cycle (cyclin B1, proliferating cell nuclear antigen (PCNA), and Ki67), growth factors (IGF-II, pleiotrophin (PTN), and midkine (MK)), and transcriptional regulation, cytoskeleton, and detoxification enzymes were identified by microarray analysis. Some of these genes were also confirmed by Northern blotting and immunohistochemistry of their RNA and protein content. In vivo treatment with PTN (20 ng/g) increased bromodeoxyuridine incorporation (by 2.24-fold) and PCNA expression (by 1.71-fold) during day 7 to day 14, indicating that PTN induces cell proliferation in mouse heart. CONCLUSIONS: Global gene expression analysis in the whole heart may be useful in understanding the orchestrated process of postnatal development or terminal differentiation in the cardiac environment. These data are likely to be helpful in studying developmental anomalies of the heart in neonates.

Animals↗

Release of cytochrome c and activation of caspases related to myocyte apoptosis in obstructed ureters in a rat model of obstructive uropathy.

OBJECTIVE: To investigate the roles of cytochrome c and caspases in the pathogenesis of muscular damage in obstructed ureters in a rat model. MATERIALS AND METHODS: Apoptotic cells were detected using in situ end-labelling of DNA fragments. The expression of cytochrome c, and caspases-3, -8 and -9 was examined in 54 rats, using immunohistochemistry. RESULTS: The severity of ureteric smooth muscle damage increased during obstruction. Apoptotic myocytes, and the expression of cytochrome c and the three caspases in the smooth muscle layer were apparent 14 days after ligation, reaching a peak at 21 days. The numbers of apoptotic cells in the smooth muscle layer correlated significantly with expression of cytochrome c and the three caspases (r = 0.8673, 0.8701, 0.5723 and 0.7910, respectively; all P < 0.01). The expression of cytochrome c in the smooth muscle layer correlated significantly with the expression of the three caspases (r = 0.8234, 0.7558 and 0.7825, respectively; all P < 0.001). The expression of caspase-3 and -8, and -3 and -9 also correlated significantly (r = 0.6721 and 0.8501, respectively; both P < 0.002). CONCLUSIONS: Cytochrome c and caspases are involved in ureteric myocyte apoptosis; the release of cytochrome c might be important in ureteric damage during obstructive uropathy.

Animals↗

Complete genome sequence of the model actinomycete Streptomyces coelicolor A3(2).

Streptomyces coelicolor is a representative of the group of soil-dwelling, filamentous bacteria responsible for producing most natural antibiotics used in human and veterinary medicine. Here we report the 8,667,507 base pair linear chromosome of this organism, containing the largest number of genes so far discovered in a bacterium. The 7,825 predicted genes include more than 20 clusters coding for known or predicted secondary metabolites. The genome contains an unprecedented proportion of regulatory genes, predominantly those likely to be involved in responses to external stimuli and stresses, and many duplicated gene sets that may represent 'tissue-specific' isoforms operating in different phases of colonial development, a unique situation for a bacterium. An ancient synteny was revealed between the central 'core' of the chromosome and the whole chromosome of pathogens Mycobacterium tuberculosis and Corynebacterium diphtheriae. The genome sequence will greatly increase our understanding of microbial life in the soil as well as aiding the generation of new drug candidates by genetic engineering.

Bacterial Proteins↗

Over-expression of apoptosis-related proteins contributes to muscular damage in the obstructed ureter of the rat.

OBJECTIVE: To determine the role of apoptosis-related proteins (Myc, Bax, Bcl-2, and Bcl-X(L)) in muscular damage in obstructed rat ureters. MATERIALS AND METHODS: The in situ end-labelling of DNA fragments and the expression of apoptosis-related proteins were assessed, using immunohistochemistry, in 54 female Sprague-Dawley rats in which unilateral ureteric obstruction was caused by ureteric ligation. RESULTS: The severity of ureteric damage increased during the period of obstruction. Apoptotic cells and the expression of Bax were detected in the smooth muscle layer from 14 days after ligation. The percentage of apoptotic cells and the expression of Bax in the smooth muscle layer increased and reached a peak 21 days after ligation, and then declined. The expression of Myc was also detected in the smooth muscle layer 14 days after ligation but reached a peak at 28 days. The expressions of Bcl-2 and Bcl-X(L) in the smooth muscle layer were only detected 21 and 28 days after ligation. The numbers of apoptotic cells in the smooth muscle layer correlated significantly with the expressions of Myc and Bax (r = 0.7360 and 0.7432, respectively; both P < 0.005), and with the expression index of Bax/Bcl-2 and Bax/Bcl-X(L) (r = 0.8909 and 0.8592, respectively; both P < 0.001). CONCLUSIONS: Apoptosis-related proteins might be important in regulating cell apoptosis in ureteric damage during the development of obstructive uropathy.

Animals↗