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D F Chen

Publications and source records attributed to D F Chen.

66 records · Page 4Linked to original sources
PubMed1987

Cloning and expression of cDNA for human poly(ADP-ribose) polymerase.

cDNAs encoding poly(ADP-ribose) polymerase from a human hepatoma lambda gt11 cDNA library were isolated by immunological screening. One insert of 1.3 kilobases (kb) consistently hybridized on RNA gel blots to an mRNA species of 3.6-3.7 kb, which is consistent with the size of RNA necessary to code for the polymerase protein (116 kDa). This insert was subsequently used in both in vitro hybrid selection and hybrid-arrested translation studies. An mRNA species from HeLa cells of 3.6-3.7 kb was selected that was translated into a 116-kDa protein, which was selectively immunoprecipitated with anti-poly (ADP-ribose) polymerase. To confirm that the 1.3-kb insert from lambda gt11 encodes for poly(ADP-ribose) polymerase, the insert was used to screen a 3- to 4-kb subset of a transformed human fibroblast cDNA library in the Okayama-Berg vector. One of these vectors [pcD-p(ADPR)P; 3.6 kb] was tested in transient transfection experiments in COS cells. This cDNA insert contained the complete coding sequence for polymerase as indicated by the following criteria: A 3-fold increase in in vitro activity was noted in extracts from transfected cells compared to mock or pSV2-CAT transfected cells. A 6-fold increase in polymerase activity in pcD-p(ADPR)P transfected cell extracts compared to controls was observed by "activity gel" analysis on gels of electrophoretically separated proteins at 116 kDa. A 10- to 15-fold increase in newly synthesized polymerase was detected by immunoprecipitation of labeled transfected cell extracts. Using pcD-p(ADPR)P as probe, it was observed that the level of poly(ADP-ribose) polymerase mRNA was elevated at 5 and 7 hr of S phase of the HeLa cell cycle, but was unaltered when artificial DNA strand breaks are introduced in HeLa cells by alkylating agents.

Carcinoma, Hepatocellular↗
PubMed1987

[Value of prophylactic irradiation to supraclavicular areas in small cell lung carcinoma--analysis of 104 patients].

A series of 104 patients with limited small cell lung carcinoma was treated by combination of chemotherapy and radiotherapy from August 1975 to July 1981. 104 patients were divided into three groups: prophylactic irradiation to supraclavicular areas (14 patients), non-prophylactic group (72 patients), non-prophylactic irradiation with positive supraclavicular lymph node metastasis after the treatment (18 patients). The 5 year survival rates of the three groups were 14%, 6% and 0%. Distant metastasis rates after the treatment were 36%, 52% and 61%, respectively. The supraclavicular lymph node metastasis rate after the treatment was higher in patients with intra-thoracic lymph node metastasis before the treatment (25%) than in those without this metastasis (0%). It is suggested that, for small cell lung cancer patients, especially with intra-thoracic lymph node metastasis before the treatment, prophylactic irradiation to the supraclavicular areas be valuable.

Adult↗
PubMed1984

Organochlorine pesticide residues in paddy fish in Malaysia and the associated health risk to farmers.

Paddy fish (Trichogaster pectoralis Regan) were collected from five sampling locations in a major paddy-growing area of Malaysia and analysed for organochlorine residues. During the same period, ten farming families, chosen at random from each of the five sampling sites, were interviewed. Information was obtained about the quantity of paddy fish consumed, the amount and type of pesticide used on the paddy-field, and the frequency of application.The pesticide residues found in the fish samples were aldrin/dieldrin, chlordane, HCH, and DDT. Only the projected maximum intake level for aldrin/dieldrin approached the acceptable daily intake as recommended by FAO/WHO; other residue levels were relatively low. However, this study considered only fish; the total daily intake of pesticide residues by the Malaysian paddy farmer may be considerably increased by consumption of other contaminated food.

Agricultural Workers' Diseases↗
PubMedDate not supplied

Internal hernia caused by Meckel diverticulum in an infant: report of one case.

Intestinal obstruction caused by internal hernia due to Meckel diverticulum is a rare disease. The condition is seldom diagnosed preoperatively. In this paper, we present a 10-month-old boy who suffered from abdominal pain, persistent vomiting, and mild fever for 2 days. Abdominal sonography, plain abdomen X-ray, and computed tomography merely showed mechanical ileus and partial malrotation. However, exploratory laparotomy revealed a Meckel diverticulum through which the small bowel had herniated. We introduce the Meckel diverticulum and internal hernia and discuss intestinal obstructions.

Hernia↗
PubMedDate not supplied

Carcinoma of the colon in a child.

A 13-year-old boy presented with carcinoma of the ascending colon. He had had intermittent abdominal pain for about one year, with body weight loss, prior to admission. Physical examination showed diffuse abdominal tenderness, but no palpable mass. Lower GI barium study and colonofibroscopic examination showed a protruding mass over the proximal ascending colon. At operation, right hemicolectomy with ileotransversecolostomy was performed, the pathologic finding was adenocarcinoma, signet-ring cell type. Although chemotherapy with 5-fluorouracil, mitomycin, and levamisole were given subsequently, the patient expired one year after surgery because of multiple metastasis. Carcinoma of the colon is extremely rare in the young. Mucin-producing adenocarcinoma is the most predominant type of colon cancer, and most are of signet-ring cell carcinoma. While prognosis is relatively bright in adult, the prognosis is quite unfavorable in children because of the preponderance of the poor histological characteristics and the difficulty of diagnosis.

Adenocarcinoma, Mucinous↗
PubMedDate not supplied

Defecographic evaluation of patients with defecation difficulties.

Defecographic studies were carried out in 36 females and 19 males with specific complaints of straining with defecation, incomplete rectal emptying and perineal descent. Of these, 91% had abnormal defecographic findings. Abnormalities were more common in females than in males. The female patients mean anorectal angles were 111.3 degrees (resting), 102.2 degrees (squeezing) and 124.7 degrees (straining). Their mean anterior rectocele size was 1.8 cm and the mean difference between the pelvic floor and the anorectal junction at rest and during maximal straining, the mean Ds-R, was also 1.8 cm. Ninety-one percent of the females had anterior rectoceles, 33% had internal rectal intussusception, 25% had hypertonic puborectalis slings and 22% had a Ds-R > 3 cm. The mean anorectal angles of the males were 116.3 degrees (resting), 102.0 degrees (squeezing) and 132.9 degrees (straining) and the mean Ds-R was 2.0 cm. Sixty-eight percent of the males had hypertonic puborectalis slings, 58% had internal rectal intussusception, and 42% had a Ds-R > 3 cm. All patients with hypertonic puborectalis slings had smaller, more acute straining angles. Males with abnormal perineal descent had a greater Ds-R than patients without perineal descent.

Adult↗
PubMedDate not supplied

Laboratory aid and ultrasonography in the diagnosis of appendicitis in children.

Forty-seven consecutive patients with clinically suspected acute appendicitis were studied at this hospital from June, 1994 to March, 1995. All the patients had received a complete study protocol including: detailed history and physical examination; complete blood cell count with differential count; erythrocyte sedimentation rate; C-reactive protein and sonographic examination. The male to female ratio is 29: 18. The age range is from 4 to 14 years. Thirty patients received laparotomy and 27 were diagnosed as appendicitis by histologic findings including 6 cases of perforated appendicitis. The remaining 3 patients had no evidence of appendicitis histologically. The other 17 patients were observed clinically. In these, the abdominal pain resolved spontaneously, or it was proved due to other diseases. The sensitivity and specificity of these laboratory examinations are: leukocytosis (> 10,000/mm3): 85. 2%, 65%; leukocytosis with a shift-to-the-left (neutrophil > 75%): 81.5%, 70%; elevated ESR (> 20 mm/hr): 40.7%, 85%; elevated CRP (> 0.9 mg/dl): 70.4%, 65%; (> 5 mg/dl); 51.9%, 95%; sonography: 85.2%, 100%. There were 4 false-negative and no false-positive ultrasonographic results in our study. Five of the 6 case of perforated appendicitis had elevated CRP levels of more than 8 mg/dl. In conclusion, detailed history taking and physical examination are still the most reliable tools for diagnosis. For the doubtful cases, sonography can provide excellent specificity and good sensitivity for differential diagnosis. The classical tools of leukocytosis and shift-to-the-left can only provide a screening property but not for diagnosis. CRP was not a good predictor in our study, but it can be a useful parameter when perforated appendicitis is suspected.

Acute Disease↗
PubMedDate not supplied

Abdominal teratomas in children.

Seventeen cases of abdominal teratoma were studied retrospectively. These patients had been diagnosed at Cathay General Hospital from 1978 to 1993. The male to female ratio was 9:8, the range of age at diagnosis was from 2 days to 13 years. The chief complaints were palpable abdominal mass in 13 patients (76%) and abdominal distention in 7 (41%). Fifteen teratomas were located in the retroperitonium; also, 1 of the 17 had gastric teratoma and another, a tumor originating from an undescended testes. The tumors were resected in all patients. Postoperative courses were smooth except for one patient, who died suddenly on the day following surgery. No further specific management was needed because the pathologic findings were all benign in nature. Ultrasonography is of benefit in locating, as well as diagnosing, abdominal teratoma. Surgical excision is curative for the majority of cases. Long term follow-up is necessary, in consideration of the rare chance of recurrence.

Abdominal Neoplasms↗
PubMedDate not supplied

Acute diffuse phlegmonous esophagogastritis: report of a survived case.

A 42-year-old man was admitted because of a persistent pain on swallowing together with epigastralgia, chest pain, fever, and shortness of breath for 5 days. An unbearable shortness of breath with a retrosternal pain was noted each time he tried to lie down. The patient also developed bilateral pleural effusion and pericardial effusion. Ten days after admission, he underwent an emergency laparotomy after an acute episode of severe epigastralgia with hematemesis and rebound tenderness limited to the epigastrium. Operative findings showed diffuse phlegmonous esophagogastritis. A near-total esophagectomy and a total gastrectomy were done. He lost 15 kilograms of body weight and was discharged 3 months later. The patient underwent reconstructive surgery 2 months after discharge, recovered well and regained his weight within one year.

Adult↗
PubMedDate not supplied

Choledochal cyst in infancy: report of two cases.

Choledochal cysts are malformations of the biliary ductal system, which rarely occur in infancy. In neonates and infants, choledochal cysts are congenital, may be associated with distal biliary atresia and typically presents with cholestatic jaundice and acholic stools characteristic of biliary obstruction. In older children and adults, it may be acquired in association with an anomalous pancreaticobiliary union and presents with any combination of intermittent jaundice, abdominal pain, and a palpable abdominal mass. Early detection of choledochal cysts is important in the prevention of the fatal complications of biliary obstruction. Here, we present two cases of congenital choledochal cyst in which the patients were 9 weeks old and 7 weeks old respectively. Both of them presented with jaundice, acholic stools, and hepatomegaly. Combined use of sonography, computed tomography and hepatobiliary scintigraphy demonstrated the presence of choledochal cysts. Thereafter, they underwent surgical excision of the cysts with Roux-en-Y reconstruction of the biliary tree; the results were successful.

Choledochal Cyst↗