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Biomedical subjects

C M Huang

Publications and source records attributed to C M Huang.

At least 19 recordsLinked to original sources

Heart transplant coronary artery disease in Chinese recipients.

BACKGROUND: Transplant coronary artery disease is the principle limiting factor for long-term survival of heart transplantation (HTx) recipients. We reviewed our data to assess the incidence of this disorder among Chinese HTx recipients and to compare it with the results of Western studies. MATERIAL AND METHODS: From July 1988 to May 2002, 182 patients received 184 orthotopic HTx. One hundred sixty-three recipients survived for at least 1 year with available SPECT scans or coronary angiogram studies. The data set included donor characteristics, recipient characteristics, active cytomegalovirus (CMV) infection rate, rejection episodes, immunosuppressants, and human leukocyte antigen (HLA) mismatches. RESULTS: Surgical mortality in our program was 4.3% and the actuarial freedom from coronary artery disease at 1, 3, and 5 years was 99%, 95%, and 92%, respectively. Angiogram results were stratified into coronary artery disease (n = 15) or absence of the disorder (n = 148) groups. Only older donor age showed statistical significance between the groups. Compared with the Western series, the present data show higher actuarial survival rates and freedom from coronary artery disease. There were statistically significant differences in regard to graft ischemia time, proportion of male recipients, ischemic heart disease, rejection episodes during the first year, and incidence of CMV infection. CONCLUSIONS: SPECT scan can detect coronary artery disease before there is significant stenosis of the coronary artery with acceptable survival rates. Chinese HTx recipients show a lower incidence of the disorder, lower rates of ischemia heart disease, lower proportion of male gender, lower incidence of CMV infection, fewer rejection episodes during the first year, and less ischemic time than Western recipients, which maybe the contributing factors to their better survival.

Adult↗

Heart transplantation at Cheng Hsin General Hospital in Taiwan: 15-year experience.

Heart transplantation (HTx) in Taiwan, which started in 1987, now includes more than 500 cases. From July 1988 to September 2003, we performed 215 cases of orthotopic HTx in 164 male and 51 female recipients of mean age of 47.3 +/- 14.3 years, (range 2.7 to 74.9 years). The leading etiologies were dilated cardiomyopathy (CMP), 68.5%; ischemic CMP, 20.2%; and valvular CMP, 4.2%. The actuarial survival rates at 1, 5, and 10 years are 88.3%, 77.1%, and 57.2%, respectively. We performed the first case of HTx in Asia after bridging for 14 days with an indigenous total artificial heart (TAH; the Phoenix-7 model); we performed the first case of infant HTx without blood transfusion and also the first case of autotransplantation of heart for repair of a left ventricular rupture after a mitral valve replacement. These cases were all successful with the longest surviving HTx recipient in Asia. We have used the biatrial anastomosis technique in all cases. We discovered familial CMP due to mitochondrial defects in two pediatric cases. Because of the scarcity of donor hearts, we have used size-mismatched hearts as well as suboptimal and hepatitis-positive donor hearts, all with satisfactory outcomes. Our experience has shown comparable results to Western programs, with efficacy and cost-effectiveness. We find the technique of biatrial anastomosis for orthotopic HTx to result in a low incidence of tricuspid regurgitation and conduction anomalies. The use of suboptimal and size-mismatched donor hearts is also promising.

Cause of Death↗

Sera from children with active Henoch-Schönlein purpura can enhance the production of interleukin 8 by human umbilical venous endothelial cells.

OBJECTIVE: To investigate the ability of sera from children with active Henoch-Schonlein purpura (HSP) to enhance endothelial interleukin (IL) 8 production and intercellular adhesion molecule (ICAM)-1 expression. METHODS: Nine children with active HSP and nine normal healthy children were enrolled. IL8 serum levels of patients and controls at different stages were analysed. Production of IL8 and expression of ICAM-1 by human umbilical venous endothelial cells were detected (ELISA for IL8, flow cytometry for ICAM-1) and compared under various stimuli, including sera of patients at different stages, sera of controls, and medium alone. RESULTS: Serum levels of IL8 were increased at the acute stage. Levels of IL8 in supernatants from human umbilical venous endothelial cells (HUVEC) co-cultured with sera from children with active HSP were significantly higher than those from HUVEC without any treatment (p = 0.001), HUVEC treated with inactive sera (p = 0.004), and HUVEC treated with sera from healthy controls (p = 0.004). Sera from patients and from controls did not enhance the expression of ICAM-1 on HUVEC. CONCLUSIONS: Some factors may be present in sera from children with active HSP that could activate endothelial cells to produce IL8. This process may account, in part, for the mechanisms of perivascular neutrophil infiltration and leucocytosis in HSP.

Acute Disease↗

Polymorphisms of the interleukin-4 gene in chinese patients with systemic lupus erythematosus in Taiwan.

We aimed to evaluate the relationship between two polymorphisms of the IL4 gene (-590T/C and intron 3) and systemic lupus erythematosus in Chinese patients in Taiwan. This study included 91 patients with systemic lupus erythematosus (SLE) and 163 unrelated, age matched healthy controls living in the same area. The typing of -590T/C and intron 3 VNTR (variable number of tandem repeats) polymorphisms were performed by PCR-RFLP and PCR, respectively. Allelic frequencies and carriage rates between SLE patients and controls were compared, and the relationship between allelic frequencies and clinical manifestations of SLE was evaluated. The genotype frequencies of IL-4 intron 3 were found to differ significantly between SLE patients with and without discoid rash (chi-square test, P = 0.03 5). The allelic frequency of intron 3 RP1 was significant different in the patients with discoid rash when compared to patients without this clinical feature (OR = 3.70, 95% CI 2.04-6.72, chi2 test, P = 0.029). The RP1/RP1 homozygous carriage was significantly associated with patients with discoid rash when compared to patients without this clinical feature (OR = 6.04, 95% CI 2.81-12.95, P = 0.01). The allelic frequency of -590T was significant different in the patients with discoid rash when compared to patients without this clinical feature (OR = 3.44, 95% CI 1.88-6.31, chi-square test, P=0.04). The T/T homozygous carriage was significantly associated with patients with discoid rash when compared to patients without this clinical feature (OR = 5.41, 95% CI 2.50-11.68, P = 0.02). We describe a novel association between RPI/RPI and T/T homozygous carriage and patients with discoid rash. The role of the intron 3 polymorphism of the IL4 gene in SLE remains unclear and further substantiation based on larger patient samples is needed.

Adolescent↗

Association of vitamin D receptor gene BsmI polymorphisms in Chinese patients with systemic lupus erythematosus.

The purpose of this study was to evaluate whether vitamin D receptor (VDR) genes BsmI polymorphisms were markers for susceptibility to or severity of systemic lupus erythematosus (SLE) in Chinese patients in Taiwan. The study included 47 Chinese patients with SLE. In addition, 90 unrelated, healthy individuals living in central Taiwan served as control subjects. Each polymorphism was detected as a result of polymerase chain reaction (PCR)-based restriction analysis. A PCR product length was determined to be 580bp (BB) whereas two fragments of 405 and 175bp were determined to be excisable lengths (bb) by BsmI endonuclease. The relationship between Bsm polymorphisms and clinical manifestations of SLE was evaluated. We found that BB was significantly more common and bb less common in SLE than in control group (chi2 = 54.2, P < 0.0001). In addition, the frequency of B allele was also significantly more common in patients with SLE than in the healthy control subjects (chi2 = 38.7, P < 0.0001), giving an odds ratio of 7.14 (95% confidence interval 3.53-14.4). In the SLE patients, we did not detect any associations of VDR genotype with the clinical, laboratory profiles, or lupus nephritis (chi2 = 2.34, P = 0.3). This study indicated an increased distribution of VDR BB genotype and B allelic frequencies in the Chinese SLE patients in Taiwan. However, there were no associations between the frequency of VDR allelic variations and clinical manifestations, laboratory profiles, or lupus nephritis.

Asian People↗

Proteomic analysis of proteins in PC12 cells before and after treatment with nerve growth factor: increased levels of a 43-kDa chromogranin B-derived fragment during neuronal differentiation.

Proteomic analysis is an important approach to characterizing the proteome and studying protein function in the post-genomic era. It is also a powerful screening method for detecting unexpected alterations in protein expression that may be missed by conventional biochemical techniques. The aim of this study was to perform a preliminary proteomic analysis of PC12 cells in order to investigate the effect of nerve growth factor (NGF) on protein expression in PC12 cells during neurite outgrowth. PC12 cell proteins were separated by two-dimensional electrophoresis (2DE) and visualized by silver staining, then certain proteins were identified by N-terminal amino acid microsequencing and a homology search of a protein sequence database. Over 400 proteins were detected, 10% of which showed a significant (greater than 30%) increase or decrease in expression during NGF-induced neuronal differentiation. Seven proteins in the 2DE map were identified; the levels of five of these were unaffected by NGF treatment, whereas the levels of the other two, beta-tubulin and a novel 43-kDa chromogranin B-derived fragment, were significantly increased by more than 30 and 200%, respectively. Our results suggest that chromogranin B processing is enhanced in PC12 cells during NGF-induced neuronal differentiation. In addition, since this increase in the levels of the chromogranin B-derived fragment was specifically blocked by PD98059, we suggest that the increased processing can be ascribed to activation of the MAP kinase pathway, and that the 43-kDa chromogranin B-derived fragment can serve as a new marker of neuronal differentiation for proteomic studies.

Animals↗

Involvement of noradrenergic innervation from locus coeruleus to hippocampal formation in negative feedback regulation of penile erection in the rat.

We demonstrated previously that a novel negative feed back mechanism for the regulation of penile erection, which is triggered by ascending sensory inputs initiated by tumescence of the penis, exists in the hippocampal formation (HF). This study further elucidated the role of the locus coeruleus (LC), which is the largest aggregate of norepinephrine-containing neurons in the brain and provides the major noradrenergic innervation to the HF, in this process. Adult male Sprague-Dawley rats that were anesthetized and maintained with chloral hydrate were used. The intracavernous pressure (ICP) recorded from the corpus cavernosum of the penis was used as the experimental index for penile erection. Electrical activation of the LC elicited a significant reduction in baseline ICP. Similar observations were obtained on microinjection bilaterally into the hippocampal CA1 or CA3 subfield or dentate gyrus of equimolar doses (5 nmol) of norepinephrine (alpha1-, alpha2-agonist), phenylephrine (alpha1-agonist), or BHT 933 (alpha2-agonist). Bilateral electrolytic lesions of the LC discernibly enhanced the magnitude and/or duration of the elevation in ICP induced by intracavernous administration of papaverine (400 microgram). A potentiation of the papaverine-evoked ICP increase was also observed following pretreatment with bilateral hippocampal application of equimolar doses (250 pmol) of either prazosin (alpha1-, alpha2B-, alpha2C-antagonist), naftopidil (alpha1A/D-antagonist), yohimbine (alpha2-antagonst), or rauwolscine (alpha2B-, alpha2C-antagonist). None of these antagonists, however, affected baseline ICP. These results suggest that noradrenergic innervation of the HF that originates from the LC may play an active role in negative feedback regulation of penile erection, engaging at least alpha1A/D-, alpha2B-, and alpha2C-adrenoceptors in the HF.

Adrenergic alpha-Agonists↗

Interleukin-1beta and interleukin-1 receptor antagonist gene polymorphisms in rheumatoid arthritis.

The purpose of this study was to evaluate if IL-1beta (IL-1beta promoter and IL-1beta exon 5) and IL-1receptor antagonist (IL-1Ra) gene polymorphisms act as markers of susceptibility to or severity of RA. The study included 104 RA patients and 103 normal controls. No significant difference was observed in the cytokine allelic frequencies of IL-1beta promoter and IL-1beta exon 5 between patients with RA and healthy controls. In addition, there was no significant association in the cytokine carriage rates of I and II allele of IL-1Ra between RA patients and healthy controls. In contrast, the IV allele of IL-1Ra was significantly increased in RA patients with low inflammatory activity (P=0.03). This study indicated that allelic frequency and carriage rate of IL-1beta (IL-1beta promoter and IL-1beta exon 5) and IL-1Ra (I and II allele) do not differ significantly between normal controls and RA patients in Taiwan. However, the carriage rate of IV allele of IL-1Ra was high in the RA patients with low inflammatory activity.

Arthritis, Rheumatoid↗

A proteomic analysis of secreted proteins from xylan-induced Bacillus sp. strain K-1.

The expression level of extracellular proteins in an alkaliphilic bacterium, Bacillus sp. strain K-1, grown in a xylan-containing medium, is significantly increased when compared with that grown in the nonxylan culture medium. A proteomic approach has been efficiently applied to separate and characterize these differentially expressed secretory proteins. Eight prominent protein spots were identified and subjected to N-terminal amino acid sequencing. The results show that three spots share considerable similarity with the xylanolytic enzymes and that two spots share considerable similarity with the GltC regulatory protein and 3-dehydroquinate dehydratase, respectively. In addition, the three other proteins show little similarity with the known proteins in the database. In conclusion, our results demonstrate that the proteomic approach is a highly efficient method to rapidly study the differential expression of the secreted proteins by Bacillus sp. strain K-1 grown under xylan-induced condition.

Bacillus↗

Gouty arthritis in a female patient with mixed connective tissue disease.

Gout with systemic lupus erythematosus (SLE) or progressive systemic sclerosis (PSS) has rarely been reported, whereas mixed connective tissue disease (MCTD) with the demonstration of intra-articular monosodium urate crystals has never been reported. We describe an unusual case of MCTD (SLE-PSS) in a 37-year-old woman who developed acute gouty arthritis. Arthrocentesis and synovianalysis may be necessary to differentiate gout from the arthropathy of MCTD.

Adult↗

Targeting delivery of paclitaxel into tumor cells via somatostatin receptor endocytosis.

BACKGROUND: The binding of somatostatin (SST) to endogenous G-protein-coupled receptors (SST receptors or SSTRs) is followed by internalization of SST, and, several reports have shown that a high density of SSTRs is present on most hormone-secreting tissue tumors. Facile synthesis of the long-acting SST analog, octreotide, has previously been described. Octreotide might be of practical value in developing tumor tracers and in serving as a carrier of cytotoxic antitumor drugs. RESULTS: Fluorescein-labeled octreotide was internalized into the cytosol of human breast MCF-7 carcinoma cells via binding to SSTRs. Octreotide-conjugated paclitaxel (taxol) was created by coupling taxol-succinate to the amino-terminal end of octreotide. This conjugate retains the biological activity of taxol in inducing formation of tubulin bundles, eventually causing apoptosis of MCF-7 cells. Cytotoxicity of octreotide-conjugated taxol is mainly mediated by SSTR, as shown by the observation that octreotide pretreatment can rescue the induced cell death. In comparison with free taxol, this conjugate shows much less toxicity in Chinese hamster ovary cells. CONCLUSIONS: Octreotide-conjugated taxol exerts the same antitumor effect of free taxol on stabilizing microtubule formation and inducing cell death. This conjugate triggers tumor cell apoptosis mediated by SSTRs and is exclusively toxic to SSTR-expressing cells. Octreotide-conjugated taxol is less toxic to low-SSTR-expressing cells compared with free taxol. Our results strongly indicated that octreotide-conjugated taxol demonstrates cell selectivity and may be used as a targeting agent for cancer therapy.

Animals↗

Diagnostic usefulness of telomerase activity in nasopharyngeal carcinoma.

Telomeres are specialized structures at the ends of eukaryotic chromosomes which are composed of simple repetitive G-rich hexameric sequences. Activation of telomerase, a ribonucleoprotein that synthesizes telomeric DNA, is found in most malignant tumors. However, little data is available concerning the correlation between telomerase activity and NPC (nasopharyngeal carcinoma). In this study, telomerase activation was determined using the TRAP (telomerase repeat amplification protocol) assay in 62 nasopharyngeal biopsies (25 NPC, 25 non-malignant nasopharyngeal lymphoid tissues, 12 post-irradiated nasopharyngeal tissues). The results showed that strong telomerase activity was present in both NPC and non-malignant nasopharyngeal biopsies. Post-irradiated nasopharyngeal samples had a significantly lower telomerase activity than NPC and non-malignant nasopharyngeal lymphoid tissues. It is well known that nasopharyngeal tissue is infiltrated by numerous lymphocytes, which might retain telomerase activity. Therefore, the finding that the telomerase activation was lowest in post-irradiated nasopharyngeal tissues is reasonable because of the destruction of activated lymphocytes and NPC by radiation. NPC biopsies with positive lymph node involvement exhibited higher levels of telomerase compared to those without lymph node involvement. Our data indicate a positive association between telomerase activity and tumor potential for lymphatic spreading in limited local tumors. In addition, telomerase activity may be useful as a diagnostic marker in the detection of tumor cells in recurrent NPC, but not in primary NPC.

Adolescent↗

Predictors of short-term outcome in Chinese patients with ambulatory heart failure for heart transplantation with ejection fraction <25%.

Heart transplantation (HT) provides longer survival than that of the natural history in patients with dilated cardiomyopathy (DCM). However, the optimal timing for cardiac transplantation and predictors of mortality in patients with end-stage cardiomyopathy (ESCM) has been poorly defined. The primary purpose of this study focused on the natural history of ambulatory patients with ESCM for HT assessment. Secondly, we tried to determine prognostic factors of individuals with the poorest short-term outcome and the optimal timing for HT in patients with ESCM. Finally, clinical treatment with angiotensin converting-enzyme inhibitors (ACEIs), carvedilol and amiodarone in the prevention of mortality caused by ESCM, were retrospectively evaluated. The short-term outcomes of 119 referral patients with ESCM for four years were observed. The patients had New York Heart Association class III to IV dyspnea at initial assessment for HT. Left ventricular ejection fraction (LVEF) was 17 +/- 6% and cardiac index (CI) was 2.0 +/- 0.6l/min/m2. After optimization of medical treatment, the patients were divided into two major groups according to CI equal to or less than 2.0l/min/m2 and more than 2.0l/min/m2. HTs were accepted in 88 patients and the patients were divided into two groups: medical treatment (group 1, 56 patients) or HT (group 3, 32 patients); HT was not accepted in the other 31 patients (group 2). We studied the probability of the survival curve and prognostic variables of the groups with medical treatment in the follow-up of 12 +/- 9 months. During follow-up, 49 patients were alive without HT. The remaining 38 patients died; 27 patients were in group 1 and 11 patients were in group 2. Eight deaths in group 2 were sudden. The actuarial survival rate among the non-HT population was 73%, 68%, 63 %, and 56 % at 3, 6, 9 and 12 months, respectively. The actuarial survival rate among group 1 was 70 %, 59 %, 55 %, and 52 % at 3, 6, 9 and 12 months, respectively. The actuarial survival rate among group 2 was 87 %, 85 %, 77 %, and 65 % at 3, 6, 9 and 12 months, respectively. A comparison, excluding patients with HT, was performed with those who had survived < 1 year and > or 1 year after assessment, and those who had died. Two parameters were independent predictors of prognosis on univariate and multivariate analysis: total pulmonary vascular resistance (TPR) > or = 14 Wood units (W) and CI < 1.65 l/min/m2 at 6 and 12 months after assessment. Treatment with amiodarone for ventricular tachycardia (VT) showed no convincing role in the prevention of sudden death in our patients. Also, treatment with ACEIs or carvedilol for heart failure was unconvincing to improve the short-term outcome in this study. Our results suggest in properly selected patients that HT should be considered within six months among patients with severe heart failure. Hemodynamic parameters associated with right cardiac function are important determinants of mortality caused by progressive heart failure. Predictors such as CI and TPR may be considered as important markers of mortality in prediction of short-term outcome in patients with ESCM, as other predictors reported in the literature.

Adolescent↗

Indolent cutaneous mucormycosis with pulmonary dissemination in an asthmatic patient: survival after local debridement and amphotericin B therapy.

We describe a 68-year-old asthmatic female patient with multiple pulmonary cavities. A preexisting ecthyma on the left lower leg became erythematous and swollen during exacerbation of her asthma which was under treatment with high-dose steroids. Nonseptate broad hyphae were found in her sputum, pus from the wound, and debrided skin tissue. Hematogenous spread of septic emboli from indolent cutaneous mucormycosis to both lungs was the suspected mechanism of dissemination. High-dose steroid therapy may have been the major contributory factor. The patient was successfully treated with local surgical debridement of the wound and intravenous amphotericin B.

Aged↗

Age-related changes in the cerebellum: parallel fibers.

Between the ages of 3 and 23 months, the cerebella of NIH Fischer 344 rats lose 30% of the thickness of the molecular layer, 60% of the length of parallel fibers, and 80% of the synaptic varicosities along parallel fibers. Nearly 60% of these synaptic varicosities disappear between 3 and 9 months. Thus, the loss of cerebellar synapses is unusual, may have begun early in life, and continue into old age, causing profound synaptic losses in older rats. In addition to serious implications to functional losses, we speculate that these synaptic losses may trigger other age-related cellular losses in the cerebellum.

Aging↗

Quantitative estimation of RNA transcripts suggests persistence of Pax-6 expression in the postembryonic chick retina.

Pax-6 is expressed during early embryonic development of the eye. Very little is known about its expression in the functionally mature retina. We have detected Pax-6 transcripts in the ganglion cell- and amacrine cell layers at days 3, 10, 17 and 31 posthatching and in 2- to 3-month-old chick retina by in situ hybridization. These observations were confirmed by a quantitative analysis. Competitive RT-PCR with a homologous internal control revealed a significant reduction (p < 0.001) in the number of Pax-6 transcripts in day 17 retina [(0.39 +/- 0.13) x 10(10)/mg tissue] compared to day 3 retina [(1.65 +/- 0.48) x 10(10)/mg tissue]. Although significantly lower than at day 3, the day 31 retina [(0.7 +/- 0.16) x 10(10)/mg tissue] and retina from 2- to 3-month-old chicks [(0.9 +/- 0.28) x 10(10)/mg tissue] contained an increased number of Pax-6 transcripts in comparison to day 17. On the basis of the amount of RNA, the number of Pax-6 transcripts in the day 3 retina [(0.45 +/- 0.14) x 10(10)/microg RNA] relative to day 17 retina [(0.4 +/- 0.08) x 10(10)/microg RNA] did not change significantly (p = 0.29). However, at day 31 and at 2-3 months of age an increased number of Pax-6 transcripts [(0.65 +/- 0.14) x 10(10)/microg RNA and (0.65 +/- 0.2) x 10(10)/microg RNA, respectively)] were found. In view of the known association of Pax-6 expression with proliferation and emergence of different cell types, these data suggest that cell types in ganglion and inner nuclear cell layers may retain proliferative potential for an extended period in the young adult retina.

Aging↗