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Biomedical subjects

C C Chen

Publications and source records attributed to C C Chen.

At least 793 records · Page 44Linked to original sources
PubMedDate not supplied

Characteristics and psychosocial problems of patients with bipolar disorder at high risk for suicide attempt.

BACKGROUND: Bipolar disorder with a history of substance abuse or suicide attempt is a strong predictor of suicide. A high comorbidity of substance use disorders may obscure the specificity of findings about suicide behaviors in Western patients with bipolar disorder. METHODS: The clinical data of Chinese bipolar patients (DSM-III-R) in Taiwan who had been naturalistically followed up for at least 15 years were obtained by a combination of chart reviews and interviews with patients and family members. The national identity numbers were used to search for deceased subjects. RESULTS: There were 158 patients originally included for chart review; 4 of them died from suicide. A 9.9% lifetime prevalence of alcohol use disorders was found in 101 final subjects who accepting interview. Multiple logistic regression showed that subjects with a history of suicide attempt (n = 53, 52.5%) were more likely to have interpersonal problems with spouse or romantic partner (adjusted odds ratio = 2.85, 95% C.I. = 0.69-11.51), occupational problems mainly maladjustment and frequently changing job (adjusted odds ratio = 3.08, 95% C.I. = 1.12-10.49), and an earlier age (< or = 22 years) of onset (adjusted odds ratio = 0.96, 95% C.I. = 0.90-1.02). LIMITATION: To use an interview schedule for assessing the psychosocial problems of clinical population limits the interpretation and generalisability of the data. CONCLUSION: Despite low comorbidity of alcohol/drug use disorders in Chinese bipolar patients, a consistently high rate of suicide attempts reinforces that bipolar disorder is a high-risk group of suicide. An earlier age of onset, interpersonal problems with spouse or romantic partner, and occupational maladjustment rather than demographic characteristics may collectively identify those at high risk of suicide attempt in bipolar disorder.

Adjustment Disorders↗
PubMedDate not supplied

QT interval effects of cisapride in the clinical setting.

PURPOSE: The clinical effect of cisapride on QT intervals was prospectively studied. SUBJECTS: Consecutive adult patients were recruited in whom cisapride was indicated for gastroesophogeal reflux, gastric ulcer, duodenal ulcer, diabetic gastroparesis or chronic constipation refractory to laxatives. Exclusion criteria included disorders and medications affecting cardiac conduction, electrolyte homeostasis, drug clearance and membrane stability. METHODS: Seventy-five patients were included and followed at 1 to 2 week intervals. Patients took cisapride 5 mg thrice daily for 1 to 4 weeks (lower dose stage), followed by 10 mg thrice daily for another 1 to 4 weeks (higher dose stage). Twelve-lead ECGs were performed before commencing cisapride (group B), at completion of the lower dose stage (group L) and at completion of the higher dose stage (group H). RESULTS: No patients experienced presyncope or syncope. Seventeen patients failing to comply, and 7 complaining of abdominal discomfort or diarrhea were excluded, leaving 51 participants. Group H's corrected QT interval (QTc) was longer than group B's by 13+/-15 ms (P<0.001), and longer than group L's by 7+/-11 ms (P<0.001). Group L's QTc was longer than group B's by 7+/-21 ms (P<0.05). QT dispersion did not differ significantly among groups. Neither torsade de pointe nor ventricular tachycardia were noted in Holter monitoring of 33 patients during the higher dose stage. CONCLUSION: cisapride dose-dependently prolongs the QT interval. Further study is needed to examine the arrhythmogenicity of cisapride in higher doses and for longer durations.

Adult↗
PubMedDate not supplied

Orthogonal subspace projection-based approaches to classification of MR image sequences.

Orthogonal subspace projection (OSP) approach has shown success in hyperspectral image classification. Recently, the feasibility of applying OSP to multispectral image classification was also demonstrated via SPOT (Satellite Pour 1'Observation de la Terra) and Landsat (Land Satellite) images. Since an MR (magnetic resonance) image sequence is also acquired by multiple spectral channels (bands), this paper presents a new application of OSP in MR image classification. The idea is to model an MR image pixel in the sequence as a linear mixture of substances (such as white matter, gray matter, cerebral spinal fluid) of interest from which each of these substances can be classified by a specific subspace projection operator followed by a desired matched filter. The experimental results show that OSP provides a promising alternative to existing MR image classification techniques.

Brain↗
PubMedDate not supplied

Representation of phase equilibrium behavior of antibiotics.

The phase equilibrium behavior of biomolecules is important both in understanding the partition mechanisms and in the design and optimization of downstream recovery processes. Chen et al. (1989) proposed a molecular thermodynamic framework that successfully represents the liquid-solid equilibrium behavior of amino acids and small peptides as functions of temperature, ionic strength, solvent compositions, and pH. Based on this theoretical framework, this paper presents recent results in representing the liquid-solid equilibrium behavior (solubilities) and the liquid-liquid equilibrium behavior (phase partitioning) of beta-lactam antibiotics, which are amino acid derivatives and important chemotherapeutic agents.

Ammonium Chloride↗
PubMedDate not supplied

Development of the coping scale for infertile couples.

Infertility treatment involves more complicated, uncomfortable, and humbling medical procedures for women, so the coping strategies used by wives may differ from those used by husbands. The purpose of this study was to develop and test a Coping Scale for Infertile Couples that would be sensitive to the differences in gender. What couples actually do to cope with infertility and whether these strategies are different between couples were also addressed. A total of 138 infertile couples participated in this study. The Coping Scale for Infertile Couples was administered with the Infertility Questionnaire, the Perceived Stress Scale, and the Jalowiec Coping Scale as measures of concurrent validity. Factor analysis extracted 4 subscales from the Coping Scale for Infertile Couples. Test-retest and internal consistency reliability were high. Paired t tests revealed that wives used the "Increasing space and Sharing the burden" strategies to a greater degree than their husbands. Husbands used the "Being the best" strategy to a greater degree than the wives. A significant correlation with distress, stress, and coping measures provided evidence of concurrent validity. Preliminary results suggest that this measure has good reliability and validity, which can contribute toward the elucidation of coping strategies used by infertile couples and assist in planning effective interventions.

Adaptation, Psychological↗
PubMedDate not supplied

The capture envelope of a flanged circular hood in cross drafts.

The flow patterns of an exterior circular hood subject to the influence of various uniform cross drafts were experimentally studied in an apparatus consisting of hood-model/wind-tunnel assembly. A two-component laser Doppler anemometer was employed to measure the velocity field on the symmetry plane. The streamline patterns were obtained from the measured velocity data. The cross draft caused a characteristic envelope similar to a half Rankine body-of-revolution to form in the flow field. The boundary of the envelope is described by a dividing streamline. All streamlines within the envelope lead to the opening; those outside the envelope evolve to the downstream area. The normalized geometry of the capture envelope is theoretically justified and correlated by modifying the potential theory of point-sink-plus-rectilinear-flow. The domain and shape of the envelope enclosing the hood opening are determined primarily by the velocity ratio between the cross draft and hood suction. The correlated formula is applicable to design the hood parameters, including the sizes of opening and flange as well as the location of contaminant sources.

Air Pollutants, Occupational↗
PubMedDate not supplied

Computer simulation of particle overlap in fiber count samples.

Fibrous aerosols are of great importance to industrial hygienists because of the severe health risks that may be associated with inhaling such particles. Previous studies on measurement error due to overloading of fibers and nonfibrous particles on the collected sample indicate that a 100-1300 fiber/mm2 filter area is the best filter loading density to reduce bias in fiber counts. The present study investigated the upper fiber and particle concentration limits for reliable counting and identification and the possibility of a procedure for correcting observed fiber counts to account for fiber masking due to overlapping particles or fibers. A computer-generated grid was used to simulate the light microscope graticule field. The resolution of 2000 x 2000 was found to accurately represent the shape of the fibers and nonfibrous particles. Bivariate lognormal distributions were used to describe the length and width distributions of the fibers. The capability of distinguishing particle-overlapped fibers (defined as the resolution index), the coverage of the graticule field, the filter surface loading density, size distributions of fibers and particles, and the fiber-to-particle concentration ratio were the primary parameters in this study. The counting efficiency was found to consistently decrease with increasing filter surface loading density and decreasing resolution index. The recommended upper limit of filter surface fiber density depended not only on the number concentration ratio but also on the filter surface loading densities and size distributions of fibers and particles. The advantage of using a thoracic preseparator on counting efficiency was calculated and found to improve counting efficiency significantly when the count median diameter of nonfibrous particles was close to or larger than the thoracic 50% cutoff point of 10 microm.

Air Pollutants, Occupational↗
PubMedDate not supplied

Capture envelopes of rectangular hoods in cross drafts.

The suction fields of the rectangular hoods of various aspect ratios varying from 0.1 to 10 that are subject to the influence of cross drafts were experimentally studied in an apparatus consisting of a hood model/wind tunnel assembly. The velocity field on the symmetry plane was measured with a two-component laser Doppler anemometer. Being under the influence of cross draft, the suction field presents a characteristic capture envelope, which is described by a dividing streamline. The characteristics of the capture envelope were found to be determined by the cross-draft to hood-suction velocity ratio R and the hood-opening aspect ratio AR. The flow characteristics of the hoods with aspect ratios less than unity were dramatically different from those with aspect ratios greater than one. If areas of the hood openings had the same values, the hydraulic-diameter normalized characteristic length scales of the capture zone of the square hood were as same as those of the circular hood. When the diameter of a circular hood was equal to the width of a square hood, the physical dimensions of the capture zones created by these two hoods coincided with each other.

Air Movements↗
PubMedDate not supplied

C-reactive protein and lactate dehydrogenase isoenzymes in the assessment of the prognosis of acute pancreatitis.

The value of serum C-reactive protein, lactate dehydrogenase isoenzymes and erythrocyte sedimentation rate in predicting the outcome of acute pancreatitis was evaluated for 57 episodes in 54 patients. Serum C-reactive protein levels on day 2, 4 and 7 after admission were significantly higher in 19 episodes of severe attacks than in 38 episodes of mild attacks (13.71 +/- 9.68, 9.00 +/- 7.54, 6.02 +/- 3.83 vs 4.78 +/- 3.91, 3.30 +/- 3.61, 1.43 +/- 2.08 mg/dL; P less than 0.0001, P less than 0.005, P less than 0.0001, respectively). The sensitivity, specificity and accuracy of predicting a severe attack were 94, 76 and 82% using C-reactive protein greater than or equal to 8 mg/dL on day 2; 67, 92 and 84% using C-reactive protein greater than or equal to 5 mg/dL on day 7; and 59, 76 and 70% using Ranson's criteria greater than or equal to 3. Increases in LDH-4 and LDH-5 isoenzymes were found in both groups, with LDH-4 being slightly higher in severe attacks than in mild attacks. There was no significant difference of erythrocyte sedimentation rate between both groups. When compared with Ranson's criteria, lactate dehydrogenase isoenzymes and erythrocyte sedimentation rate, C-reactive protein is more valuable in the early assessment of the severity of acute pancreatitis.

Acute Disease↗
PubMedDate not supplied

Endoscopic sinus surgery and postoperative intravenous aminoglycosides in the treatment of atrophic rhinitis.

A total of 29 atrophic rhinitis patients were treated by endoscopic sinus surgery between 1990 and 1995. After the surgery, a 7 to 10-day course of systematic aminoglycoside was administered. Two cases were excluded, due to later occurrence of nasal lymphoma in one patient and incompleteness of postoperative antibiotic therapy in the other. Among those included, atrophic rhinitis occurred in the absence of prior surgery in 24 patients, and the condition was secondary to a previous intranasal surgery in the other three patients. After a 1 to 6-year follow-up (mean: 63.4 months), seven patients were successfully managed without any characteristic symptom or sign of atrophic rhinitis. Another 18 patients felt improved. Only two patients did not have any improvement. The rate of improvement was 92.6%. Overall, one patient suffered from a left retrobulbar hematoma after operation. Exposed orbital fat was observed in the other patient. The orbital complication rate was therefore 7.4%. No other major complication occurred in this series. The bacteriologic, radiological, antroscopic, and pathologic findings are also included here. It is concluded that endoscopic sinus surgery in combination with adequate postoperative antibiotic therapy can significantly treat atrophic rhinitis.

Adolescent↗
PubMedDate not supplied

Choledochal cyst in infancy: a follow-up study.

From January 1980 to February 1997, 19 cases, 8 males and 11 females, of choledochal cyst were diagnosed before one year old. The majority of patients were diagnosed by ultrasonography before 6 months old (15/19; 79%), including two diagnosed prenatally. According to Todani's classification, type Ia was the most common (74%), followed by type Ic (26%). Fourteen patients underwent Roux-en-Y choledocho- or hepatico-jejunostomy and cyst excision, 3 patients underwent Kasai operation, and I patient underwent external biliary drainage only. The remaining one patient with Trisomy 18 anomaly refused operation. Four of the 10 patients in whom liver histologic examinations were performed, had liver cirrhosis. The follow-up period of these patients ranged from 6 months to 9 years, with a mean of 4.1 years. We divided these 19 cases into 2 groups, according to the presence or absence of biliary atresia. In the 7 infants with biliary atresia (37%), all presented with jaundice and alcoholic stool. Two patients died due to delayed presentation and surgery, both had liver cirrhosis. One patient is living with liver cirrhosis. Another patient was lost to follow-up, but frequent cholangitis was noted till 8 months old. The remaining 3 patients are living and well. In the 12 without biliary atresia, 9 patients are living and well. Two patients died, one due to Trisomy 18 anomaly and the other with delayed surgery and liver cirrhosis. One case was lost to follow-up. In summary: 1-) a possibility of the association of biliary atresia in infants with choledochal cyst should be carefully searched and considered as a unique group; 2) ultrasonography is a good diagnostic tool in choledochal cyst during prenatal or infancy period; 3) the mortality cases were characterized by prolonged bile stasis, biliary cirrhosis, delayed surgery, or multiple anomalies; 4) surgery should be performed as early as possible for those with persistent jaundice and light colored stools.

Choledochal Cyst↗
PubMedDate not supplied

Immunogenicity and reactogenicity of two recombinant hepatitis B vaccines in healthy adolescents on two-dose schedule.

This is an open, randomized study to compare the immunogenicity and reactogenicity of two recombinant hepatitis B virus (HBV) vaccines. The HBV-NF is a new formulation with a new adjuvant phenoxyethanol which replaced the conventional adjuvant of a commercially available recombinant HBV vaccine (Engerix-B). These two vaccines had the same 20 micrograms hepatitis B surface antigen (HBsAg). They were administered to the deltoid muscle of 116 healthy adolescents, aged between twelve and eighteen years, according to the 0, 6-month schedule. Serum was taken at month 0, 1, 6, and 7. Antibody to HBsAg was tested by radioimmunoassay. Geometric mean titers of both vaccines displayed no significant difference at month 1, 6, and 7. Following the second dose of vaccine, the seroprotection titer (10 mIU/ml) rates at month 7 were 90.9% in HBV-NF and 93.4% in Engerix-B, respectively (p = 0.43). The incidences of local and general adverse reactions were from 3% to 7% without significant difference between the two vaccines and the reactions were all mild and tolerable. Based on this study, regimens of this two-dose schedule proved to be safe and immunogenic, which may provide a cost-effective alternative for HBV mass vaccination program in adolescents.

Adolescent↗
PubMedDate not supplied

Nonfunctioning pancreatic tumor manifestated as abdominal mass in a child.

This report concerns a 9-year-old girl with a nonfunctioning pancreatic tumor presented as an abdominal mass. An encapsulated tumor, measuring approximately 8 x 7 cm, was found during operation, and debulking surgery was done. Histopathologic studies proved that it was a pancreatic tumor, compatible with non-functioning islet cell tumors. She displayed neither clinical picture of jaundice, nor excessive hormonal manifestations such as diarrhea or flushing. No evidence would suggest its association with multiple endocrine neoplasia type I. To our knowledge, it has never been reported in children in Taiwan.

Abdominal Pain↗
PubMedDate not supplied

[The coexistence of vesicoureteral reflux and ureteropelvic junction obstruction in children].

From January 1982 to December 1990, there were 229 cases with 337 ureters having vesicoureteral reflux (VUR). Thirteen of them (3.86%) were also found to have ureteropelvic junction (UPJ) obstruction in the same ureter. They were categorized into three groups based on the therapeutic implications. Group 1 (two ureters) underwent pyeloplasty. Group 2 (two ureters) received both pyeloplasty and reimplantation. The remaining nine ureters having VUR and pseudo-obstruction fell into group 3, and two of them became true UPJ obstruction eventually. We stressed the importance of evaluating upper urinary tract in all refluxed ureters with inappropriately dilated renal pelvis. By doing that we can avoid unnecessary surgery and prevent complications from wrong sequence of operation to a least extent.

Child↗
PubMedDate not supplied

Renal cell carcinoma in childhood: report of one case.

Renal cell carcinoma is extremely rare in children. A case is reported here of renal cell carcinoma in a seven-year-old boy whose clinical manifestations were fever and right loin pain. Imaging studies revealed a solid mass in the right kidney and a metastatic nodule over the middle lobe of the right lung. Right nephrectomy and middle lobectomy of the right lung were performed. Pathologic examination revealed a renal cell carcinoma with predominance of clear cells. Despite Stage IV, the patient is still alive without chemotherapy and radiotherapy. It should be emphasized that renal cell carcinoma should be included in the differential diagnosis of pediatric renal solid masses, particularly in older children and adolescents.

Carcinoma, Renal Cell↗
PubMedDate not supplied

The management of anorectal malformations.

From 1982 to 1990, 120 cases of anorectal malformation (84 males and 36 females) were admitted to Mackay Memorial Hospital; 101 cases were corrected surgically. Among these, 40 cases were high (H) or intermediate (I) type, and 61 cases were low (L) type. In the 40 cases of the H and I type, 13 (Group 1) received Stephens' procedure (SPR) and the remaining 27 (Group 2) received Peña's procedure (PSARP). For the L type, translocation anoplasty, cut-back anoplasty and limited PSARP were employed in 10, 45 and 6 cases, respectively. Anorectal continence results were evaluated by Kiesewetter's criteria. In Group 1, the results were good in 25%, fair in 17% and poor in 58%. In Group 2, the results were good in 70% and fair in 30%. In addition to better anorectal continence, the PSARP resulted in a lower rate of major complications. In the L type, the results were excellent without significant difference among the types of surgery employed.

Anal Canal↗
PubMedDate not supplied

Hepatoblastoma in infancy and childhood: a clinical and pathological study of 32 cases.

During the twenty-nine-year period from June 1959 to October 1988, 32 infants and children with histology-proved hepatoblastoma were seen at the Department of Pediatrics, National Taiwan University Hospital (NTUH). The age at diagnosis ranged from four days to six years, with a mean of one year and eight months. Most of the patients (87.5%) were under the age of three. There was no sex predilection (16 males, 16 females). The most common presenting signs were an upper abdominal mass (71.9%) and/or abdominal distention (62.5%). Physically, all the patients revealed hepatomegaly, with or without mass. Laboratory abnormalities included primarily thrombocytosis (64.3%), elevated serum aspartate aminotransferase (75.0%), serum alanine aminotransferase (62.5%), cholesterol (78.3%) and alphafetoprotein (92.3%). According to the classification of Ishak and Glunz, 56.3% of these belonged to the epithelial type; the others belonged to the mixed type. During the follow-up period, 6 patients with complete resection of the tumor remained alive from 2 years to 17 years and 4 months. Twenty-two patients died from 8 days to 16 months after diagnosis. Four patients were lost to follow-up. The two-year survival rate was 21.4% (6/28). Complete resection of the tumor was the key treatment for achieving survival.

Carcinoma, Hepatocellular↗