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Biomedical subjects

C C Chuang

Publications and source records attributed to C C Chuang.

At least 19 recordsLinked to original sources
PubMed2006

Blockade of interleukin 6 accelerates acinar cell apoptosis and attenuates experimental acute pancreatitis in vivo.

BACKGROUND: It remains unclear whether interleukin (IL) 6 plays a role in initiating either the inflammatory or antiapoptotic responses in severe acute pancreatitis. This study examined the effect of neutralizing antibody against IL-6 on the induction of pancreatic acinar cell apoptosis and attenuation of the severity of severe acute pancreatitis. METHODS: Experiments were conducted on laboratory mice with severe acute pancreatitis induced by lipopolysaccharide injection following six injections of caerulein at intervals of 6 h. Neutralizing monoclonal anti-IL-6 antibody was administered either 5 min or 2 h after the first caerulein injection. Apoptosis in pancreatic sections was determined by the terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick-end labelling method. RESULTS: Administration of caerulein and LPS induced an increase in serum amylase and IL-6 levels, severe acute pancreatitis, pancreatitis-associated lung injury, and phosphorylation of signal transducer and activator of transcription (STAT) 3 in the pancreas. A neutralizing antibody against IL-6 effectively suppressed these responses. Application of IL-6 neutralizing antibody caused the induction of apoptosis in the pancreatic acinar cells of mice with acute pancreatitis. CONCLUSION: Blocking IL-6 suppresses STAT-3 activation in the pancreas and consequently attenuates the severity of severe acute pancreatitis by promotion of pancreatic acinar cell apoptosis.

Amylases↗
PubMed2005

Treatment of nanosized TiO2-containing wastewater by simultaneous electrocoagulation/electrofiltration.

In this work, a simultaneous electrocoagulation/electrofiltration (EC/EF) treatment module was employed to treat nanosized TiO2-containing wastewater. Nanosized TiO2-containing wastewater was obtained and treated by a self-designed EC/EF treatment module. To evaluate the performance of this novel treatment module, the effects of electric field strength (EFS), transmembrane pressure (TMP), and crossflow velocity (CV) on permeate qualities were investigated. Permeate qualities of concern included pH, turbidity, conductivity, chemical oxygen demand (COD), and total organic carbon (TOC). A full factorial design of experiments was adopted in this work. First, by keeping TMP and CV constant the effects of EFS on permeate qualities were studied. In this set of testing, it was noticed that an application of electric field greatly increased the filtration rate, which was further influenced by the magnitude of EFS. In all cases, the filtration rate decreased as the treatment time elapsed due mainly to fouling of the membrane. Further tests were conducted to study the effects of TMP on permeate qualities by keeping EFS and CV constant. Finally, the effects of CV on permeate qualities were studied by keeping EFS and TMP constant. It was found that the optimal operating conditions would be electric field strength of 166.7 V/cm, transmembrane pressure of 1 kgf/cm2, and crossflow velocity of 0.22cm/s. Under such conditions, permeate would have the following qualities: (1) pH, 6.32; (2) turbidity, 2.41 NTU; (3) conductivity, 15.11 microS/cm; (4) COD, 100.0 mg/L; and (5) TOC, 512.6 mg/L.

Carbon↗
PubMed2004

Impact of an outbreak of severe acute respiratory syndrome on a hospital in Taiwan, ROC.

STUDY OBJECTIVE: To estimate the impact of the severe acute respiratory syndrome (SARS) outbreak in early 2003 on a tertiary care hospital in Taiwan, ROC. METHODS: The study estimated the utilisation of resources related to infection control, SARS related medical services, and routine medical services, and SARS related medical outcomes at National Cheng Kung University Hospital (NCKUH) from 25 March to 16 June 2003 through a cross sectional survey of hospital records. RESULTS: A mean of 5100 persons per day (95%CI 4580 to 5610) underwent fever screening at the outpatient and emergency department (ED) entrances to the hospital, of which 35 per day (95% CI 30 to 40) were referred for further evaluation for suspected or probable SARS. ED isolation surge capacity was created via 12 new beds outside the ED: eight for SARS assessment, three for patients awaiting in hospital bed assignment, and one for resuscitation. A total of 382 patients were fully evaluated for suspected or probable SARS outside the ED, of which 27 were admitted. The mean numbers of outpatient clinic patient visits, ED visits, ED trauma patient visits, ED admissions, hospital admissions, and operative procedures decreased during the outbreak. Thirty eight patients were hospitalised with suspected SARS, of which three received the final diagnosis of probable SARS. Two patients with probable SARS died. No cases of nosocomial SARS transmission occurred. CONCLUSIONS: This SARS outbreak was associated with substantial use of hospital and ED resources aimed at infection control, comparatively less use of resources related to the medical care of patients with suspected or probable SARS, and decreased use of routine medical services.

Bed Occupancy↗
PubMed2001

Emergency medical technicians' disaster training by tabletop exercise.

The objective of this study was to assess the attitudes of emergency medical technicians (EMTs) toward tabletop drills to determine the effect of tabletop simulation on the EMT student perception of disaster preparedness and management. In November 1998 and April 1999, 59 firefighters underwent 260 hours of EMT intermediate level training at the National Cheng Kung University Hospital in Tainan, Taiwan. All participants had experience in field disaster exercise training before they attended this EMT training course. The EMT courses included a disaster and mass-casuality incident program. A 9-item questionnaire was completed by the 59 EMTs before (for field exercise) and after undergoing the tabletop drills. The results of the survey revealed that the field operation exercise could not provide adequate provisions to link the results of disaster exercises to appropriate changes in terms of training, equipment, supplies, and plans. Field operation failed to show the ability of others to fill in during the absence of key officials. Tabletop drilling provided better performance for these 2 issues. Tabletop exercise also provided a better chance than field exercise to evaluate the response without the use of telephones, which are not always reliable in real emergency situation. For disaster exercises, limitations of field operation drills such as communications, coordination, assignment of responsibilities, and postevent mitigation priorities were noted, and tabletop drills provided additional benefits for these settings. Large-scale effect evaluation of different drills may be necessary to design future disaster preparedness programs.

Adult↗
PubMed1999

Purification, characterization and molecular cloning of trichoanguin, a novel type I ribosome-inactivating protein from the seeds of Trichosanthes anguina.

The seeds of the plant Trichosanthes anguina contain a type I ribosome-inactivating protein (RIP), designated trichoanguin, which was purified to apparent homogeneity by the combined use of ion-exchange chromatographies, i.e. first with DE-52 cellulose and then with CM-52 cellulose. The protein was found to be a glycoprotein with a molecular mass of 35 kDa and a pI of 9.1. It strongly inhibits the protein synthesis of rabbit reticulocyte lysate, with an IC50 of 0.08 nM, but only weakly that of HeLa cells, with an IC50 of 6 microM. Trichoanguin cleaves at the A4324 site of rat 28 S rRNA by its N-glycosidase activity. The cDNA of trichoanguin consists of 1039 nt and encodes an open reading frame coding for a polypeptide of 294 amino acid residues. The first 19 residues of this polypeptide encode a signal peptide sequence and the last 30 residues comprise an extension at its C-terminus. There are four potential glycosylation sites, located at Asn-51, Asn-65, Asn-201 and Asn-226. A comparison of the amino acid sequence of trichoanguin with those of RIPs such as trichosanthin, alpha-momorcharin, ricin A-chain and abrin A-chain reveals 55%, 48%, 36% and 34% identity respectively. Molecular homology modelling of trichoanguin indicates that its tertiary structure closely resembles those of trichosanthin and alpha-momorcharin. The large structural similarities might account for their common biological effects such as an abortifacient, an anti-tumour agent and anti-HIV-1 activities. Trichoanguin contains two cysteine residues, Cys-32 and Cys-155, with the former being likely to be located on the protein surface, which is directly amenable for conjugation with antibodies to form immunoconjugates. It is therefore conceivable that trichoanguin might be a better type I RIP than any other so far examined for the preparation of immunotoxins, with a great potential for application as an effective chemotherapeutic agent for the treatment of cancer.

Amino Acid Sequence↗
PubMed1999

Abdominal weight and inspiratory resistance: their immediate effects on inspiratory muscle functions during maximal voluntary breathing in chronic tetraplegic patients.

OBJECTIVE: To study the immediate effects of maximal voluntary (MV) breathing, with and without abdominal weight (AW) or inspiratory resistance (IR), on inspiratory muscle functions in chronic tetraplegic patients. DESIGN: A crossover trial design. SETTING: Rehabilitation department of a university hospital. PARTICIPANTS: Nine tetraplegic men injured at the C4 to T1 levels, with a mean duration of injury of 72.8 months. INTERVENTIONS: Each subject performed MV breathing without and with AW load (AWMV breathing) and IR load (IRMV breathing) separately. MAIN OUTCOME MEASURES: Electromyographic (EMG) activity of the inspiratory muscles, mouth pressure, inspiratory flow, and inspiratory volume. RESULTS: AWMV breathing evoked greater diaphragmatic EMG activity, inspiratory flow, and inspiratory volume than did IRMV breathing, although the increase of diaphragmatic EMG activity was not statistically significant. Conversely, IRMV breathing produced greater sternocleidomastoid EMG activity and negative mouth pressure than did AWMV breathing. Both AWMV and IRMV breathing evoked greater inspiratory muscle EMG activity than did MV breathing. CONCLUSION: AW and IR loads have differential immediate effects on the inspiratory muscle functions during MV breathing in patients with chronic tetraplegia, suggesting that these two breathing maneuvers may have dissimilar mechanisms of training in such patients. The muscle EMG activity evoked during MV breathing with AW or IR is greater than that without a mechanical load, implying that mechanically loaded training in tetraplegic patients results in load compensatory adjustments via their respiratory motor output to improve respiratory function.

Abdomen↗
PubMed1999

Homology modeling of cephalopod lens S-crystallin: a natural mutant of sigma-class glutathione transferase with diminished endogenous activity.

The soluble S-crystallin constitutes the major lens protein in cephalopods. The primary amino acid sequence of S-crystallin shows an overall 41% identity with the digestive gland sigma-class glutathione transferase (GST) of cephalopod. However, the lens S-crystallin fails to bind to the S-hexylglutathione affinity column and shows very little GST activity in the nucleophilic aromatic substitution reaction between GSH and 1-chloro-2,4-dinitrobenzene. When compared with other classes of GST, the S-crystallin has an 11-amino acid residues insertion between the conserved alpha4 and alpha5 helices. Based on the crystal structure of squid sigma-class GST, a tertiary structure model for the octopus lens S-crystallin is constructed. The modeled S-crystallin structure has an overall topology similar to the squid sigma-class GST, albeit with longer alpha4 and alpha5 helical chains, corresponding to the long insertion. This insertion, however, makes the active center region of S-crystallin to be in a more closed conformation than the sigma-class GST. The active center region of S-crystallin is even more shielded and buried after dimerization, which may explain for the failure of S-crystallin to bind to the immobilized-glutathione in affinity chromatography. In the active site region, the electrostatic potential surface calculated from the modeled structure is quite different from that of squid GST. The positively charged environment, which contributes to stabilize the negatively charged Meisenheimer complex, is altered in S-crystallin probably because of mutation of Asn99 in GST to Asp101 in S-crystallin. Furthermore, the important Phe106 in authentic GST is changed to His108 in S-crystallin. Combining the topological differences as revealed by computer graphics and sequence variation at these structurally relevant residues provide strong structural evidences to account for the much decreased GST activity of S-crystallin as compared with the authentic GST of the digestive gland.

Algorithms↗
PubMed1998

Clinically silent primary adrenal lymphoma: a case report and review of the literature.

Primary adrenal lymphoma (PAL) is extremely uncommon. We describe a case of clinically silent non-Hodgkin's B-cell lymphoma of diffuse large cell type with exclusive left adrenal localization. The tumor was discovered by computed tomography (CT) as a 2.5-cm dense mass and diagnosed at autopsy. Literature concerning this unusual neoplasm is reviewed. During the early stage, particularly when the lesion is small, PAL is likely to be missed. This unusual entity should be included in the differential diagnosis of adrenal masses so that early diagnosis may be made and intervention might dramatically affect the clinical outcome.

Adrenal Gland Neoplasms↗
PubMed1998

Prevalence study of thyroid dysfunction in the elderly of Taiwan.

The present study was aimed at investigating the prevalence of thyroid dysfunction in the elderly, aged 65 years or older, in a community of southern Taiwan. By using the records of the local household registry, a sampling frame for the elderly population was constructed, and a sample of 1,400 subjects was drawn by simple random sampling. After the exclusion of nonresponse subjects, 917 subjects aged between 65 and 88 years (mean 71.9) were included in our survey. The serum thyrotropin levels of these participants were measured by monoclonal antibodies TSH immunoradiometric assays. A normal range, 0.45-4.65 microU/ml, was determined from the middle 95% of the TSH distribution of 140 'disease-free' subjects. By reference to the normal range, 23 (2.51%) participants had high (> 4.65 microU/ml), and 41 (4.47%) had low (< 0.46 microU/ml) TSH levels. The overall prevalence of thyroid dysfunction in the sample was 6.98%. Of the 23 participants with high TSH levels, 8 (34.8%) had low free T4 values (< 1.21 ng/dl), so-called overt hypothyroidism, and of the 41 participants with low TSH levels, only 1 (2.4%) had high T3 values, so-called T3 thyrotoxicosis. Antithyroid antibodies were found in 56.5% of those with high TSH levels but only 12.2% of those with low TSH levels (odds ratio = 8.53, 95% confidence limits = 2.55-28.50, p < 0.001). This result indicates that autoimmune disease is still the major cause of hypothyroidism in aged people. However, the prevalence of subclinical hyperthyroidism is higher than that of subclinical hypothyroidism and it might relate to nonautoimmune factors.

Aged↗
PubMed1998

Clinical experience with pendimethalin (STOMP) poisoning in Taiwan.

The herbicide pendimethalin (STOMP) shares a similar chemical structure with nitro compounds such as dinitrobenzene, which was previously demonstrated to cause methemoglobinemia in mammals. However, reports on STOMP poisoning in humans are rare. We reviewed 71 STOMP poisoning cases (42 men and 29 women of mean age 43.9 +/- 2.5 y) reported to the Poison Control Center--Taiwan from September 1986 to September 1997 and summarized their clinical manifestations. Two incidences resulted from skin and eye contact. The rest were due to oral ingestion intentionally or accidentally. The average ingestion was 106.1 +/- 13.4 ml. Among them, 20 cases had no symptoms or signs, 38 had mild effects such as nausea, vomiting and sore throat, 7 had effects such as severe retching, hematemesis and seizures. Four patients expired due to also taking other herbicides (mainly organophosphates) and because of inadequate airway management. Adequate ventilation support was the major therapy in salvaging the poisoning cases.

Adult↗
PubMed1998

Evidence for the involvement of protein kinase C in the inhibition of prolactin gene expression by transforming growth factor-beta2.

We investigated the mechanisms by which transforming growth factor (TGF)-beta2 inhibited prolactin mRNA expression in GH3 rat pituitary tumor cells. Maximal inhibition was observed with cells exposed to 5 ng/ml TGF-beta2 for 24 hr. Continuous presence of the hormone during the entire period was not necessary because exposure of cells to TGF-beta2 for 20 min was sufficient to trigger the same extent of prolactin mRNA inhibition at 24 hr as with its persistent presence. The action of TGF-beta2 could be abolished by cycloheximide or EGTA, suggesting the requirement of a newly synthesized protein and extracellular Ca2+. The response of prolactin mRNA to TGF-beta2 was inhibited by preincubation of cells with phorbol-12-myristate-13-acetate, which down-regulated protein kinase C (PKC). The activities of both the cytosolic and membrane PKC were significantly reduced at 20 min after TGF-beta2 addition, and inhibition continued to 24 hr, the last time point analyzed. However, the ratio of cytosolic to membrane PKC was not altered by TGF-beta2. Inhibition of PKC did not require the sustained presence of TGF-beta2. In vitro kinase assays of the immunoprecipitated PKC demonstrated that the activities of alpha, epsilon, mu, and zeta isozymes were significantly decreased in the TGF-beta2-treated cells, whereas that of PKClambda was not affected. Western blotting did not reveal any change in PKCepsilon steady state protein levels, suggesting TGF-beta2 inhibits PKC activity through a post-translational mechanism. Our results support that inhibition of PKC activity is an early event mediating TGF-beta2-inhibited prolactin mRNA expression in GH3 cells.

Animals↗
PubMed1997

Quality of life of spinal cord injured patients in Taiwan: a subgroup study.

The major purposes of this study were to assess the quality of life (QOL) of spinal cord injured patients, and to assess the possible factors affecting the QOL. The survey was conducted from 1992-1993 by mailed questionnaires to members of Spinal Cord Injury Association of the Republic of China. There were 347 quality responses with the mean age of 37.5 +/- 10.2 years old and the mean duration of illness of 7.8 +/- 6.8 years. The questionnaire included five domains, physical mobility, environment-transportation, psychosocial adjustment, education and economics for a total of 39 items. Each item contained a rating of 'importance' and 'satisfaction'. The quality of life index (QLI) was calculated by multiplying the satisfaction score with the importance score, then dividing by the possible highest score. The major results included: (1) the subjects had mild to moderate dissatisfaction with most items in five domains except psychosocial adjustment: (2) quality of life in those with complete tetraplegia (QLI = -0.41) and incomplete tetraplegia (QLI = -0.31) was significantly lower than that of those with complete paraplegia (QLI = -0.13) and incomplete paraplegia (QLI = -0.04); (3) both the severity of injury and the post-injury working status were the major factors affecting the life quality of spinal cord injured patients in Taiwan.

Adult↗
PubMed1997

Metacarpal hand: classification and guidelines for microsurgical reconstruction with toe transfers.

Metacarpal hand refers to the hand that has lost its prehensile ability through amputation of all fingers with or without amputation of the thumb. Functional restoration can be achieved by a wide variety of microvascular toe transfer techniques. When deciding which procedure should be used, careful consideration must be given to the level of amputation of the fingers as well as the functional status of the remaining thumb. In this article we propose a classification for the various patterns of the metacarpal hand along with guidelines for selection of the proper toe transfer procedure.

Adult↗
PubMed1996

Study of structure-activity correlation in destruxins, a class of cyclodepsipeptides possessing suppressive effect on the generation of hepatitis B virus surface antigen in human hepatoma cells.

A new destruxin [destruxin E2 chlorohydrin] was isolated from the culture medium of Metarrhizium anisopliae and its structure was determined by NMR spectroscopy and mass spectrometry. As compared with other destruxins, the new destruxin showed a lower suppressive activity on the production of hepatitis B virus surface antigen in human hepatoma Hep3B cells. NMR study coupled with molecular modeling by computer graphics has revealed that the hydrophobicity nature of the convex surface characteristic of all destruxin molecules plays an important role in their biological activity.

Antiviral Agents↗
PubMed1996

Protein engineering of venom toxins by synthetic approach and NMR dynamic simulation: status of basic amino acid residues in waglerin I.

The tertiary structure of waglerin I has been determined by NMR and dynamic simulated annealing [Chuang et al., Biochim. Biophys. Acta 1292, 145-155 (1996)]. It is believed that the peptide basicity of waglerin may play an important role for its activity due to its high content of basic amino acids. In order to investigate the active site of the toxin, seven analogues of waglerin, [Ala3]-waglerin, [Ala7]-waglerin, [Ala10]-waglerin, [Ala14]-waglerin, [Ala18]-waglerin, [Ala20]-waglerin and [Ala22]-waglerin have been synthesized chemically by single replacement of basic amino acid residues one by one with Ala. By correlation of structures for each analogue with LD50 toxicity bioassays, it is found that the [Ala10]-waglerin exhibits no toxicity and the active site of the native toxin seems to reside in the proximity of the disulfide loop, which is spatially close to His10. Furthermore, the closer is the disulfide loop to the basic amino acid in waglerin, the more influential is the basic amino acid on the toxicity of waglerin. Based on the tertiary structure of waglerin, the structures of all synthetic analogues were derived based on computer-simulated modelling. By the pair-wise structural comparison, the disulfide loop in [Ala10]-waglerin analogue is found to be twisted as compared to the native form, in agreement with the lack of toxicity for this synthetic analogue.

Amino Acid Sequence↗
PubMed1996

Conformation of Vespa basalis mastoparan-B in trifluoroethanol-containing aqueous solution.

Mastoparan-B, a tetradecapeptide isolated from the venom of the hornet Vespa basalis, belongs to the mastoparan analogs of vespid venom with the lysine residues common for all mastoparan family toxins at positions 4, 11 and 12. Here we use 1H-NMR spectroscopy and hybrid distance geometry-simulated annealing calculation to investigate its three-dimensional structure in trifluoroethanol-containing aqueous solution. The calculated structure shows that residues 3-14 adopt an amphiphilic alpha-helical structure in which the residues with hydrophilic side chains (i.e. Lys-4, Ser-5, Ser-8, Lys-11, Lys-12) are located on one side and the residues with hydrophobic side chains (i.e. Leu-3, Ile-6, Trp-9, Ala-10, Val-13, Leu-14) located on the other side of the molecule. The overall structural features a very similar to the conformation of mastoparan-X reconstituted in vesicle [Wakamatsu et al. (1992) Biochemistry 31, 5654-5660] in spite of the substitutions made for eight residues with distinctly different hydrophobicity. These substitutions lead to a larger hydrophobic moment for the alpha-helical segment and further mobilized N-terminal. This study will help reveal the conformational significance of mastoparan toxins with respect to their potency and activity in G protein regulation.

Amino Acid Sequence↗
PubMed1996

The salvage of a degloved hand skin flap by arteriovenous shunting.

Nine cases of hand degloving injuries were treated successfully with arteriovenous shunting technique. Of these nine cases, four were degloved from the wrist level and one from the forearm, three were degloved at the palm and one at the dorsum of the hand. All injuries resulted in distally based skin flaps, which were either superficial to the palmar fascia or within the subcutaneous layer. Lack of active bleeding from the periphery of the avulsed flaps substantiated circulatory compromise before revascularization. Survival of the avulsed flaps was achieved by directing the proximal arterial flow into the venous channel within the avulsed skin flaps. The post-operative care and rehabilitation were straightforward, and functional results were satisfactory.

Adolescent↗