Search PubMed⌕ Search

Biomedical subjects

C N Chen

Publications and source records attributed to C N Chen.

At least 37 records · Page 2Linked to original sources
PubMed1998

Laparoscopic subtotal gastrectomy with lymphadenectomy in a patient with early gastric cancer.

Laparoscopic surgery is rapidly gaining in popularity among general surgeons. It is not widely used to treat abdominal malignancies because of technical difficulties and the fear of peritoneal dissemination. We describe the use of laparoscopic surgery to treat early gastric cancer. A 66-year-old man was diagnosed with early gastric adenocarcinoma by endoscopic ultrasonography and biopsy. Subtotal gastrectomy along with removal of the perigastric (D1) and selective extraperigastric lymph nodes over the celiac trunk was accomplished laparoscopically, through five punctures and a minilaparotomy. The patient's convalescence was uneventful. Bowel sounds were heard on postoperative day 1. On postoperative day 3, he passed flatus. The patient was started on a clear liquid diet on postoperative day 5. There was neither leakage nor obstruction after oral intake. He was discharged on postoperative day 11. No local recurrence or distant metastasis was found during 16 months' follow-up. This is the first report of successful laparoscopic resection of early gastric cancer with lymph node dissection in Taiwan.

Aged↗
PubMed1997

Analysis of exon/intron structure and 400 kb of genomic sequence surrounding the 5'-promoter and 3'-terminal ends of the human glypican 3 (GPC3) gene.

GPC3, the gene modified in the Simpson-Golabi-Behmel gigantism/overgrowth syndrome (SGBS), is shown to span more than 500 kb of genomic sequence, with the transcript beginning 197 bp 5' of the translational start site. The Xq26.1 region containing GPC3 as the only known gene has been extended to > 900 kb by sequence analysis of flanking BAC clones. Two GC isochores (40.6 and 42.6% GC) are observed at the 5' and 3' ends of the locus, with a large repertoire of repetitive sequences that includes an unusual cluster of four L1 elements > 92% identical over 2.8 kb. Eight exons, accounting for the full 2.4-kb GPC3 cDNA, have been sequenced along with neighboring intronic regions. PCR assays have been developed to amplify each exon and exon/intron junction sequence, to help discriminate instances of SGBS among individuals with overgrowth syndromes and to facilitate mutational analysis of lesions in the gene.

Amino Acid Sequence↗
PubMed1997

Simultaneous determination of imipramine, desipramine and their 2- and 10-hydroxylated metabolites in human plasma and urine by high-performance liquid chromatography.

A simultaneous assay for imipramine, desipramine and their 2- and 10-hydroxy-metabolites using high-performance liquid chromatography (HPLC) is described. The drugs and internal standard, pericyazine, were extracted from plasma or urine at pH 9.6 with diethyl ether and back-extracted into 0.1 M orthophosphoric acid. The recovery of the compounds ranged from 78.6% for imipramine to 94.3% for 2-hydroxydesipramine. The extracts were analysed by reversed-phase HPLC with electrochemical detection using a mobile phase of 30% acetonitrile in 0.1 M K2HPO4 at pH 6.0 delivered at 2 ml/min. All compounds were resolved in a run time of 15 min with lower limits of quantification of 1.5 ng/ml for hydroxy-metabolites and 3 ng/ml for imipramine and desipramine. The intra- and inter-day coefficients of variation at 50 ng/ml were 5.2% and 6.8%, respectively (n=8).

Adult↗
PubMed1997

Seroprevalence of Helicobacter pylori in patients with surgical peptic ulcer.

BACKGROUND: Helicobacter pylori is known as a major cofactor in ulcerogenesis. However, the role of H pylori in surgical patients with peptic ulcer and its possible influence on surgical treatment is unclear. OBJECTIVES: To determine the prevalence of H pylori infection in surgical patients with complicated peptic ulcer diseases and analyze its clinical significance. DESIGN: A prospective, controlled study. SETTING: University-affiliated hospital and tertiary care center. SUBJECTS: Two study groups: surgical group (n = 66), i.e., patients who received surgical treatment for their peptic ulcer disease), and control group (n = 377) comprising 3 subgroups: normal volunteers (NV subgroup, n = 136) and patients who required only medical treatment for duodenal ulcer (DU subgroup, n = 119) or gastric ulcer (GU subgroup, n = 122) from January 1, 1994 to June 30, 1995. METHODS: Preoperative or overnight fasting serum samples were collected, and H pylori state was assessed by serum anti-H pylori IgG. RESULTS: Seropositivity was similar between the surgical group (60.6%) and NV control subgroup (58.8%), but it was highest in the DU control subgroup (87.4%) (P < .001 compared with NV control subgroup), followed by GU control subgroup (76.2%) (P < .01 compared NV). The patients with surgical peptic ulcer who had both seropositive and seronegative results for H pylori were similar for sex, age, social status, ulcer history, associated major medical problems, use of nonsteroid anti-inflammatory drugs, ulcer location, type of surgery, and ulceration recurrence rate. Although patients who underwent elective surgery had a higher seroprevalence rate (88.9%) than those requiring emergency surgery (56.4%) and patients who were seronegative for H pylori seemed to be associated with a higher major morbidity, these results were not statistically significant. CONCLUSION: No significant association of H pylori infection and peptic ulcer was noted between patients who required surgical treatment compared with those who required only medical treatment; H pylori played only a limited role in the cause of disease in surgical patients, perhaps only in the cases complicated with stenosis or intractable ulcers. This suggests that presently adequate acid reduction procedure will still be the main objective of surgical treatment and prevention of the ulcer recurrence.

Adult↗
PubMed1997

Endoscopic removal of nasogastric tube sutured unintentionally to gastrojejunostomy.

A nasogastric tube mistakenly sutured to the anastomotic site is a rare surgical error during gastrointestinal operation. When it does happen, proper management will prevent subsequent complications. If resistance is experienced when pulling the nasogastric tube after gastrointestinal surgery, it should never be pulled more forcefully. The endoscope should be introduced to document the etiology and to provide treatment after 2 weeks postoperation based on the wound healing process and strength of suture materials.

Endoscopy↗
PubMed1996

Ordered shotgun sequencing of a 135 kb Xq25 YAC containing ANT2 and four possible genes, including three confirmed by EST matches.

Ordered shotgun sequencing (OSS) has been successfully carried out with an Xq25 YAC substrate. yWXD703 DNA was subcloned into lambda phage and sequences of insert ends of the lambda subclones were used to generate a map to select a minimum tiling path of clones to be completely sequenced. The sequence of 135 038 nt contains the entire ANT2 cDNA as well as four other candidates suggested by computer-assisted analyses. One of the putative genes is homologous to a gene implicated in Graves' disease and it, ANT2 and two others are confirmed by EST matches. The results suggest that OSS can be applied to YACs in accord with earlier simulations and further indicate that the sequence of the YAC accurately reflects the sequence of uncloned human DNA.

Bacteriophage lambda↗
PubMed1996

Cough mixture misuse in Hong Kong--an emerging psychiatric problem?

Cough mixture misuse has become a focus of concern in Hong Kong since the late 1980s. Psychiatric admissions related to cough mixture misuse have been reported with increasing frequency during the past 5 years. A retrospective chart review of psychiatric admissions related to cough mixture misuse for a 54-month period was conducted in two psychiatric units in Hong Kong. Twenty-seven subjects were identified. The main psychiatric presentations included acute organic brain syndrome, schizophreniform psychosis and affective episode. They appeared to be associated with the pharmacological activities of opiates, antihistamines and sympathomimetics, the main ingredients of most cough mixtures.

Adolescent↗
PubMed1996

Long-range sequence analysis in Xq28: thirteen known and six candidate genes in 219.4 kb of high GC DNA between the RCP/GCP and G6PD loci.

DNA comprising 219 447 bp was sequenced in nine cosmids and verified at > 99.9% precision. Of the standard repetitive elements, 187 Alus make up 20.6% of the sequence, but there were only 27 MERs (2.9%) and 17 L1 fragments (1.6%). This may be characteristic of such high GC (57%) regions. The sequence also includes an 11.3 kb tract duplicated with 99.2% identity at a distance of 38 kb. The region is 80-90% transcribed and 12.5% translated. Thirteen known genes and their exon-intron borders are all accurately predicted at least in part by GRAIL programs, as are six additional genes. From centromere to telomere, the orientation of transcription varies among the first eight genes, then runs centromeric to telomeric for the next five, and is in the opposite sense for the last six. Eighteen of the 19 genes are associated with CpG islands. Two islands are exact copies in the 11.3 kb repeat units, and could thus give rise to double dosage levels of an X-linked gene. Another island is associated with two genes transcribed in opposite directions. From the sequence data, three genes and their exon structure are inferred. One of them, previously associated with HEX2, is shown to be a different gene unrelated to hexokinases; a second gene, previously known by an EST, is plexin, from its 65.5% identity with the Xenopus analog; and a third is a subunit of a vacuolar H-ATPase, and is named VATPS1.

Base Sequence↗
PubMed1996

Clinicopathologic characteristics and prognosis of gastric stump cancer.

To evaluate the prognosis of patients with gastric stump cancer after previous distal gastrectomy for benign gastroduodenal disease, we compared 25 patients with resected gastric remnant cancer with 143 patients with primary cancer in the upper third of the stomach. The histopathological differences between gastric remnant cancer and primary cancer were not significant, except for esophageal invasion. The percentage of esophageal invasion in gastric remnant cancer is 16%, significantly lower than 56.6% in primary cancer. The overall 5-year survival rates were 46% and 25% for patients with resected remnant cancer (n = 25) and resected primary cancer (n = 143), respectively, and there was no statistical difference between the two groups. The 5-year survival rates for gastric remnant cancer with stage I or II and primary cancer with the same stages were 89% (n = 11) and 39% (n = 50), a statistically significant (p < 0.02) difference. On contrast, the 5-year survival rate for gastric remnant cancer with stage III or IV was 0%, which was significantly worse than 17% for primary cancer with the same stages (p < 0.05). The prognosis of gastric remnant cancer is better than that of primary cancer in the upper third of the stomach at its early stages, but it is worse at its late stages. An aggressive resection is recommended for gastric stump cancer.

Adolescent↗
PubMed1996

Surgical treatment of peptic ulcer disease: changing patterns in the past 40 years.

During the past 40 years (1951-1990), 7,663 patients with peptic ulcer disease underwent surgical treatment at the National Taiwan University Hospital. A great change in patient characteristics and operative procedures was noted between the last 10 years and the previous three decades. There were 7,105 patients (92.7%) between 1951 and 1980, an average of 237 patients per year. However, only 558 patients received surgery in the last 10 years, an average of 56 patients per year. The proportion of female patients increased from 9.5% in the earlier period to 20.4% in the last 10 years; the average age of patients also increased. In the earlier period, the indications for surgery were hemorrhage (38.4%), perforation (36.1%), intractable pain (16.4%) and stenosis (9.1%). Perforation (89.2%) was the most common indication for surgical treatment in the last 10 years. Hemorrhage (4.9%), pain (4.1%) and stenosis (1.8%) were less common. There was no significant difference in surgical morbidity between the two periods. Primary subtotal gastrectomy (SG) accounted for 75.4% of operations in the earlier period, but vagotomy became the main treatment in the last 10 years, including highly selective vagotomy (HSV) (31.9%), and truncal vagotomy with drainage procedure (TV + D) (31.0%). The surgical mortality in the earlier period was 1.3% for SG, 1.8% for TV + D and 16.1% for simple closure. There was no significant change in ulcer location between the two periods. The overall mortality rate was higher in the last 10 years (5.2%) than in the earlier 30 years (2.7%) (p < 0.001). In follow-up studies, the satisfactory rate after operation was similar among patients receiving SG (89.8%), HSV (90.3%) and TV + D (91.1%) between 1977 and 1990.

Adolescent↗
PubMed1996

Endoscopically-assisted duodenal feeding tube placement using a nasogastric tube: preliminary two-year experience.

Our initial 2-year experience using a new technique of nasoduodenal feeding tube placement with a soft nasogastric tube is presented. This technique was used for patients with major burns to initiate early, safe enteral feeding. With the use of double loops in the tube and endoscopic assistance, the placement of the nasogastric tube beyond the second portion of the duodenum was accomplished in approximately 20 minutes. A method of transpyloric duodenal intubation using a soft, unstented nasogastric tube that allowed rapid bedside nasoduodenal intubation, with the patient in the supine position, was used. The tube placement technique minimizes the suffering of critically ill patients and the labor of clinicians performing the tube placement.

Burns↗
PubMed1995

Some new insights into bladder function in infancy.

OBJECTIVES: To evaluate normal bladder function and micturition patterns in infants. PATIENTS, SUBJECTS AND METHODS: Twenty-one infants (16 boys, five girls; mean age 5.9 months) with no lower urinary tract pathology underwent natural filling cystometry. Micturition patterns were also observed simultaneously with polysomnography in 26 healthy neonates (16 boys, 10 girls; mean age 7.4 days). RESULTS: In infants, cystometry showed (95% CI) a capacity of 42-53 mL, a maximum rise in detrusor pressure during voiding of 95-120 cmH2O and a voiding efficiency (voided volume/capacity) of 0.86-0.91. On micturition, urinary flow was discoordinated from peak detrusor pressures in 10 infants. Detrusor instability occurred in one of 21 infants. Micturition was observed only during wakefulness or on arousal from sleep. In neonates, 17 of 61 recorded voids (28%) were during full wakefulness and 44 (72%) during arousal from sleep. Notably, none of the recorded voids occurred during quiet sleep. CONCLUSIONS: The normal infant's bladder was stable and emptied almost completely. Voiding with incomplete co-ordination between detrusor contraction and urinary sphincter relaxation could be normal. Micturition never occurred during quiet sleep. There was cortical arousal in response to a full bladder even in new-born infants. This contradicts the traditional concept of a totally uninhibited bladder in infancy. There are potential implications for the management of children with nocturnal enuresis.

Female↗
PubMed1994

Sleep paralysis in Chinese: ghost oppression phenomenon in Hong Kong.

Despite reports of wide variation in the prevalence of sleep paralysis among different ethnic groups, there has never been any study in Chinese. In Hong Kong, a condition known as ghost oppression is descriptively identical to sleep paralysis. To examine this phenomenon, the response of 603 undergraduate students to a questionnaire were analyzed. Thirty-seven percent had experienced at least one attack of ghost oppression. There was no sex difference in the prevalence, and the peak age of onset was at the range of 17-19 for both sexes. A strong familial association was found and 20% of subjects reported a positive family history. Over one sixth of the subjects identified sleep disruption and stress as precipitating events.

Adolescent↗
PubMed1994

Narcolepsy in Hong Kong Chinese--a preliminary experience.

BACKGROUND: Narcolepsy is a sleep disorder of unknown aetiology. Despite the widely reported strong association with HLA DR2 among different ethnic groups and their varying prevalence rates, there has never been any series of laboratory documented narcolepsy in Chinese. AIMS: To report the preliminary experience with Chinese narcoleptic patients and their HLA typing. METHODS: The records of 342 patients who presented to our sleep laboratory for various sleep problems from 1986 to 1992 were examined. Both clinical and polysomnographic data were analysed. The criteria for a diagnosis of narcolepsy is based on shortened mean sleep latency of less than 5 minutes and presence of rapid eye movement (REM) sleep in two or more of the five 20-minute naps during multiple sleep latency test (MSLT). RESULTS: There were five narcoleptic patients documented resulting in an overall laboratory prevalence of 1.5% or 2.3% of patients presenting with hypersomnia. All patients were HLA DR2 positive. CONCLUSION: There is 100% association with HLA DR2 in Hong Kong Chinese narcoleptic patients. Based on the laboratory prevalence, the prevalence rate of narcolepsy among Hong Kong Chinese population is estimated to be within the range of four in 10,000 to one in 100,000.

Adolescent↗
PubMed1994

A patient with coexisting narcolepsy and morbid jealousy showing favourable response to fluoxetine.

A 37 year old Chinese man suffered from coexisting narcolepsy and morbid jealousy which were precipitated by head injury 5 years previously. Fluoxetine 20 mg/day reduced his narcoleptic symptoms and morbid jealousy but not his sleepiness. On defaulting treatment, the patient's symptoms and marital problem recurred. A common central serotonin disturbance might be involved in mediating the sleep disorder and associated psychopathology.

Accidents, Traffic↗