Biomedical subjects

L T Chen

Publications and source records attributed to L T Chen.

At least 55 records · Page 3Linked to original sources

PubMed1996

Computed tomography, endoscopic ultrasonography and intraoperative assessment in TN staging of gastric carcinoma.

In a prospective study from November 1989 to December 1993, the accuracy of computed tomography (CT), endoscopic ultrasonography (EUS) and intraoperative surgical assessment were compared for the evaluation of the depth of invasion (T category) and involvement of lymph nodes (N category) in patients with gastric carcinoma. Sixty-nine consecutive patients who received preoperative CT and EUS underwent subsequent surgery. CT and EUS results were compared with histopathologic staging of tumor invasion depth and regional lymph node metastasis (pT and pN categories). T categories were staged correctly in 42% of the cases by CT, 71% by EUS and 55% by intraoperative surgical assessment. CT correctly staged 49% of N1 and N2 lymph nodes compared with 65% for EUS and 45% for intraoperative surgical assessment. CT was more accurate for advanced cancer but had a tendency to understage the T and N categories. EUS was more accurate for serosal cancer and displayed a tendency to overstage T categories and understage N categories. Intraoperative surgical assessment overstaged early T stages, understaged the T4 stage and had a tendency to overstage N categories. CT and intraoperative surgical assessment of T and N categories were of limited value in the staging of gastric carcinoma compared to EUS. EUS is a valuable form of assessment to evaluate gastric cancer staging before surgery.

Adenocarcinoma↗

PubMed1996

Clinicopathologic study of gastric carcinoma with duodenal invasion.

Clinicopathologic features of 319 patients who underwent gastrectomy for adenocarcinoma of stomach were studied whether disease involved duodenum or not. Thirty-eight patients (11.9%) had duodenum invasion. Gastric carcinoma with duodenal invasion was most often Borrmann III or Borrmann IV (65.8%) type, with pylorous invasion by endoscopy (39.5%), large tumor size (73.7% > or = 5cm), lymph node metastasis (78.9%), serosal invasion (97.4%) and the incidence of the resection line not being free was high (13.2%). Duodenal invasion was most often (55.3%) direct through the deep layer or through lymphatics or venules. We need to pay more attention to finding duodenum invasion. More than 3 cm width of duodenal resection is recommended if duodenum invasion is suspected.

Adenocarcinoma↗

PubMed1995

Effect of 5-fluorouracil on methotrexate transport and cytotoxicity in HT29 colon adenocarcinoma cells.

Exposure of the human colon adenocarcinoma HT29 cells to different concentrations of 5-fluorouracil (5FU) for 24 h resulted in a dose-dependent increase in the cellular glutathione (GSH) level which remained elevated up to 72 h following 5FU treatment. Pretreatment of HT29 cells with 5FU was found to enhance the uptake of methotrexate (MTX) as compared to control cells. Administration of MTX 24 h after 5FU was found to be synergistic, whereas administration of MTX 24 h before 5FU or together with 5FU was not found to be synergistic. The results of this study suggest that the increase in cellular GSH level as a result of 5FU pretreatment may play a role in the enhancement of MTX uptake and the cytotoxicity of both drugs in HT29 cells.

Adenocarcinoma↗

PubMed1995

Cruciferous vegetables and glutathione: their effects on colon mucosal glutathione level and colon tumor development in rats induced by DMH.

The effect of a diet containing 10-40% lyophilized cabbage or broccoli as cruciferous vegetable or 10-40% lyophilized potato as noncruciferous vegetable fed for 14 days on the colon mucosal glutathione (GSH) level was studied in male rats. The GSH levels of the duodenum mucosa and the liver were also measured. Cabbage and broccoli enhanced the colon and duodenum mucosal GSH levels in a dose-related manner; potato had no effect. All three vegetables had no effect on the liver GSH level. The effect of GSH on colon tumorigenesis induced by 1,2-dimethylhydrazine (DMH) was also examined in rats. Male Sprague-Dawley rats were injected with DMH (20 mg/kg body wt) weekly for 20 weeks. DMH lowered the colon mucosal GSH level. GSH (100 mg/day/rat) dissolved in the drinking water and given to rats during and after DMH injections had little or no effect on tumor incidence and total number of colon tumors. Tumors were larger in rats that received GSH than in those that received water. This study shows that the colon mucosal GSH level can be enhanced by feeding rats a diet high in cabbage or broccoli and that GSH added to the drinking water did not affect DMH-induced colon tumorigenesis under the experimental conditions used.

1,2-Dimethylhydrazine↗

PubMed1995

Utility of Argyrophilic nucleolar organizer regions (AgNOR) in differentiating malignant from benign of colorectal tumors.

BACKGROUND: Argyrophilic nucleolar organizer regions (AgNOR) can reflect the activity of cellular proliferation. The purpose of this study is to evaluate the potential value of AgNOR in differentiating benign from malignant colon epithelial neoplasms, and to determine the correlation between the nucleus AgNOR and the grade of colonic adenocarcinomas. METHODS: In this study, AgNOR technique was applied to 61 paraffin embedded sections of colorectal tissue including normal mucosa (n = 10), adenomatous polyp (n = 16), and adenocarcinoma (n = 35). RESULTS: The mean +/- standard error (SE) numbers of AgNOR dots per nucleus of normal mucosa, adenomatous polyp, and adenocarcinoma were 2.17 +/- 0.07 (n = 10) 3.89 +/- 0.10 (n = 16) and 5.52 +/- 0.10 (n = 35), respectively (p < 0.00001). In addition, the mean numbers of AgNOR dots per nucleus of well differentiated (WD) adenocarcinoma (n = 14), moderately differentiated (MD) adenocarcinoma (n = 11) and poorly differentiated (PD) adenocarcinoma (n = 10) were 5.20 +/- 0.12, 5.81 +/- 0.20, 5.67 +/- 0.15, respectively. MD and PD tumor had significantly higher AgNOR count than that of WD tumor (p < 0.05). However, there was no significant difference between MD and PD colorectal adenocarcinoma. CONCLUSION: AgNOR method is a simple, rapid method in diagnosis of colorectal tumors, and it provides a useful adjunct to histopathology in the diagnosis of colorectal tumors.

Adenocarcinoma↗

PubMed1995

Technetium-99m albumin scintigraphy in the diagnosis of protein-losing enteropathy: a case report.

A 34-year-old female presenting with bilateral lower leg edema and distended abdomen was admitted to our hospital. The serum albumin was 1.42g/dl. Renal function and hepatic function were normal. Urinalysis did not show proteinuria. Tc-99m albumin scintigraphy was arranged for this patient to rule out protein-losing enteropathy. The results demonstrated loss of albumin into the intestines. We conclude that Tc-99m albumin scintigraphy of the abdomen is a valuable adjunct in the diagnosis of protein-losing enteropathy.

Adult↗

PubMed1995

Variable tissue reactions and endocrine responses to a jugular catheter.

Although the use of soft catheter materials allows for safe long-term venous access in humans and animals, a significant percentage of individuals react adversely. We have studied a group of 52 male rats over 30 days (d) for the category and degree of tissue responses to silicone-based catheters implanted in the jugular vein. Included in this evaluation was blood withdrawal at multiple intervals for assay of plasma hormones corticosterone (CORT) and prolactin (PRL) as they were correlated with the immune phenomena associated with early (5-7d) obstruction of the catheter tip. The intravascular portion of all catheters were covered with a transparent sheath which was composed of endothelial cells, smooth muscle cells, fibroblasts and numerous collagen fibers. Early blockage of catheters was the result of large white masses (wm) enclosing the tip which were continuous with the sheath. The wm consisted of: a) an inner zone nearest the catheter in some regions predominantly composed of numerous platelets and in others granulocytes and platelets; b) a middle zone containing numerous neutrophils; c) an outer zone containing a few inflammatory cells and many spaces filled with red blood cells. Rats that developed a wm blockage 7-10d after catheter placement had higher plasma CORT levels (3-5d post implant) when compared to those of animals with catheters remaining open 3-4 weeks. When viewed together, these observations describe a subset of a larger population of rats that have a local intravascular inflammatory reaction to silicone-based catheters. This preparation may be a useful model for investigating reported differences in human reactivity to silicone-based prostheses.

Animals↗

PubMed1995

Does Helicobacter pylori infection play a role in the pathogenesis of non-ulcer dyspepsia--a study of gastric emptying time.

UNLABELLED: To investigate the relationship between gastric motility and Helicobacter pylori infection in patients with non-ulcer dyspepsia, 28 patients and 10 asymptomatic healthy persons underwent gastroduodenal endoscope examinations and scintigraphic test of solid phase gastric emptying time using Chinese fried rice as a test meal. Clinical symptoms were also recorded using questionnaires for scoring. Half emptying times for ingested food (t1/2) between H. pylori infected (190.86 +/- 112.53 minutes) and uninfected patients (227.69 +/- 179.29 minutes) were not different statistically. Seven of the 15 patients with H. pylori infection (46.6%) had delayed gastric emptying time (t1/2 > 197.7 minutes), compared to 4 out of 13 without infection (30.07%) (p > 0.05). There was also no association between the status of H. pylori infection and severity of clinical symptoms (total symptoms scores: H. pylori positive: 10.07 +/- 3.84; H. pylori negative: 7.62 +/- 2.25) (p > 0.05). Seven patients from whom H. pylori was found to have been eradicated using triple therapy (colloid bismuth subcitrate 120 mg q i d, tetracycline 500 mg q i d and metronidazole 250 mg q i d for 14 days) did not show significant changes in gastric emptying time (before: 171.14 +/- 128.13; after: 158.57 +/- 182.49 minutes) but showed improvement in total symptoms scores (before: 9.28 +/- 3.85; after: 3.85 +/- 4.22) (p = 0.0277). CONCLUSIONS: infection by H. pylori in patients with non-ulcer dyspepsia did not influence solid phase of gastric emptying time and was not associated with clinical symptoms. Eradication of H. pylori infection relieved the clinical symptoms of the patients with non-ulcer dyspepsia.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1994

Reappraisal of gastroduodenal lesions after transcatheter arterial chemoembolization of liver neoplasms--selective versus superselective method.

Twenty-six patients with liver neoplasm receiving transcatheter arterial chemoembolization (TAE) therapy underwent gastroduodenal endoscopic examinations before and after TAE. The balloon was inflated in the common hepatic artery before chemoembolization if superselective cannulation beyond the gastroduodenal artery could not be done. Sixteen of the 26 patients (61.5%) showed new gastroduodenal lesions, with superficial gastritis in six, one or more erosions in nine, and hemorrhagic gastritis in five. The frequency of lesions detected was no different when the common hepatic artery was obstructed (60.0%) than when superselective embolization was done in more peripheral branch(es) (60.0%). No clinical events indicating upper gastrointestinal bleeding were noticed after TAE. The presence of esophageal and/or gastric varices and session(s) of TAE performed before did not affect the occurrence of gastroduodenal lesion(s). We conclude that TAE produces erosive gastroduodenal lesions that are detected by endoscopic examination but are clinically unimportant; balloon catheter occlusion of the common hepatic artery did not result in more frequent gastroduodenal complications than the ordinary superselective chemoembolization method.

Adult↗

PubMed1994

Long-term follow-up and serological study after triple therapy of Helicobacter pylori-associated duodenal ulcer.

OBJECTIVE: The purpose of this study was to monitor the change of IgG antibodies to Helicobacter pylori during the course of a long-term follow-up after the eradication of H. pylori, as well as to evaluate the efficacy of triple therapy in preventing the recurrence of duodenal ulcer (DU). METHODS: Twenty-three DU patients with positive H. pylori were studied; among those patients, 20 ulcers healed after initial treatment of triple therapy. Each patient received a follow-up endoscopy and biopsy examination every 3 months for 1 yr, or whenever the ulcer symptoms recurred. Serological tests for IgG antibodies were performed with a commercial ELISA. RESULTS: Of the 20 patients with healed ulcers, one dropped out of this study; the recurrence rate of DU at 1 yr was 5% (1/19). There was no recurrence of ulcer in 17 H. pylori-negative patients and only one recurrence out of two H. pylori-positive patients. After the eradication of H. pylori, the seroconversion rates of IgG were 5%, 21%, 42%, 76%, and 94% at 0, 3, 6, 9, and 12 months, respectively. After 6 months, 95% (18/19) of the patients in which H. pylori was eradicated had at least a one-grade fall in IgG titers (p < 0.001). One patient had a relapse of H. pylori which was accompanied with re-elevating IgG titers. CONCLUSIONS: We conclude that seroconversion, which usually occurs after 1 yr, indicates complete eradication of H. pylori. Furthermore, we suggest that the success of the eradication of H. pylori can be judged without endoscopic examination, 8 months after treatment by triple therapy, according to the fall of IgG titers or seroconversion. Re-elevating IgG titers may be a warning of the possibility of relapse or reinfection of H. pylori.

Anti-Ulcer Agents↗

PubMed1993

MRI demonstration of peritoneal ligaments and mesenteries.

The normal appearances of 14 peritoneal ligaments and mesenteries were demonstrated by magnetic resonance imaging (MRI). Antegrade or retrograde air introduction was employed to distend and mark the gastrointestinal tract. Delineation of these ligaments and mesenteries was helped by the presence of ascites and air-distended bowel loops. The different intraperitoneal compartments are also demonstrated.

Humans↗

PubMed1993

The use of MRI in bowel obstruction.

Nine patients with clinical or radiographic evidences of bowel obstruction were examined by magnetic resonance imaging. Retrograde insufflation of 1000-1200 ml of air through a Foley catheter placed in the rectum was employed. Scopolamine was used to inhibit bowel peristalsis and possibly relax the ileocecal valve. The administered air successfully distended the colon and the small bowel distal to the obstruction in seven of the nine cases. The air-filled small bowel loops were useful in delineating the obstruction sites and adjacent lesions in these seven cases. The diagnosis was established by means of surgery in six cases and by clinical course in three cases. The causes of obstruction included four peritoneal carcinomatoses, and one each of supravesical hernia, intussusception, adhesive band, benign granulomatous stricture, and radiational stricture. The site of obstruction was the distal small bowel in eight cases, and the rectosigmoid colon in one case.

Female↗

PubMed1993

Abdominal MR imaging following antegrade air introduction into the intestinal loops.

Air was used to distend the gastrointestinal tract and act as a contrast medium to effectively delineate the other abdominal organs/masses and to outline intraluminal or mural lesions. We used a nasogastric tube to introduce air into the stomach. Metoclopramide was administered to propel air throughout the gastrointestinal tract. Bowel peristalsis was then controlled by scopolamine butylbromide. Most of the alimentary tract could be distended by air. The normal bowel walls were barely visible between intraluminal signal-void air and extraluminal high-signal fat. Intraluminal tumor, wall thickening, and adjacent structures could be clearly delineated.

Adolescent↗

PubMed1993

Retrograde air insufflation in MRI: a technical note.

Retrograde air insufflation was employed to distend the colon and the ileum in 18 patients and five volunteers for magnetic resonance examination. Good and moderate marking of the ileum was obtained in 18 cases. The colon was nearly completely distended in every case. Intraluminal tumor, mural thickening, and extraluminal lesion were outlined by intraluminal air and surrounding air-distended bowel. This study shows that retrograde air insufflation is a useful method to mark the colon and most parts of the ileum.

Adult↗

PubMed1993

Eradication of Helicobacter pylori infection and the recurrence of duodenal ulcers.

The purpose of this study was to compare the performance of different regimens on Helicobacter pylori (H. pylori) eradication and duodenal ulcer recurrence. During a four-week period, 59 patients with duodenal ulcers who were positive for H. pylori infection were randomly treated with one of three regimens. Seventeen patients were treated with ranitidine, 19 with colloidal bismuth subcitrate (CBS), and 23 with triple therapy (CBS, tetracycline and metronidazole). Forty-six patients with healed ulcers after treatment received follow-up for six months without maintenance therapy. The recurrence rates of duodenal ulcers confirmed by endoscopy in these three groups were 64%, 33% and 0% at the third month, and 73%, 67% and 5% at the sixth month, respectively. In the ranitidine therapy group, H. pylori infection was still present at the final follow-up. In the CBS therapy group, H. pylori was suppressed initially, but recurred in all cases. In the triple therapy group, there was only one case in which H. pylori infection persisted and where ulcer recurrence occurred after 3.5 months. The remaining cases were all H. pylori negative and had no recurrence of duodenal ulcers during the six months of follow-up. Overall, 19/27 (70%) patients positive for H. pylori had a recurrence of duodenal ulcers, while none of the 19 patients who were negative for H. pylori had a recurrence of ulcers at the sixth month. This study shows that triple therapy is more effective than the other two regimens in the eradication of H. pylori and in reducing the recurrence of ulcers. H. pylori may play a role in the recurrence of the duodenal ulcer.

Adolescent↗

PubMed1992

MRI manifestations of peritoneal carcinomatosis.

Three cases of proved peritoneal carcinomatosis were examined by magnetic resonance imaging (MRI). Air was used to distend the entire gastrointestinal tract via an antegrade method. The findings included seedings along the small intestine, transverse and sigmoid colon, stellate pattern in the mesentery, plaque-like and bulky tumor masses in the mesentery and greater omentum, and focal thickenings along the right subdiaphragmatic parietal peritoneum. Stenosis caused by tumor encasement at the duodenojejunal junction and ileocolic anastomosis were first detected by MRI and later confirmed by barium studies. Ascites was present in all cases. One case showed ascites located only along the left paracolic gutter. This report shows that MRI is also able to demonstrate peritoneal carcinomatosis by using air as a gastrointestinal contrast medium.

Adenoma, Bile Duct↗

PubMed1992

[Flow cytometric analysis of DNA in esophageal cancer].

Malignancy is the first of the ten leading causes of death in Taiwan area, however, since 1978, esophageal cancer is on the first ten causes of malignancy. Esophageal cancer is an aggressive neoplasm with a generally poor prognosis. This is usually related to the advanced stages of the neoplasm at presentation and at diagnosis. In this study, the DNA content in tumor was analyzed by flow cytometry, and compared it with clinical- pathological data, especially the survival time. All thirty seven cases (36 male, 1 female, mean age: 56.5 +/- 10.3 y/o) received operation at Kaohsiung Medical College Hospital in the past 11 years and 29 cases (27 male, 2 female, mean age: 62.2 +/- 9.6 y/o) proved to be esophageal cancer by endoscopic biopsy were assayed in this study. The formalin fixed-paraffin embedded block is used to analyze DNA content by flow cytometry. After comparing these results with clinical-pathological data, there were no significant difference in sex, age, duration, tumor location and length. However, there is a significant correlation between ploidy and tumor cell differentiation, that is, most of the diploid cells were well differentiated while most of the aneuploid cells were poorly differentiated. The median survival time of diploid cases was 325 days which was longer than the 277 days in aneuploid group, but there was no significant difference between these two groups. The same result was noticed in DNA index. Multiple variables analysis of prognostic factors disclosed that there were significant difference in correation with age tumor location tumor length, and whether there was combined radiotherapy and operation. But there were no significant relationship between survival and DNA ploidy DNA index distant metastasis surrounding tissue invasion sex duration and tumor cell differentiation. These data suggest that DNA folw cytometry analysis alone, may not provide a sueful biologic basis for the variable prognosis seen with esophageal tumors.

Aged↗

PubMed1992

Comparison of omeprazole and nizatidine in the treatment of duodenal ulcers.

This study compares the efficacy and side effects of omeprazole and regular- and double-dose nizatidine in the treatment of duodenal ulcers. Duodenal ulcer healing rates in these three groups (omeprazole, 20 mg qd; nizatidine, 300 mg hs and 600 mg hs) were 81.8%, 19% and 30%, respectively, after two weeks of therapy; and 90.5%, 70% and 84.2%, respectively, after four weeks of treatment. Omeprazole had a significantly better healing rate than nizatidine, 300 mg or 600 mg, after two weeks of treatment (p < 0.01), but not after four weeks of treatment. Omeprazole relieved the ulcer pain sooner than nizatidine (p < 0.05). Smoking decreased the duodenal ulcer healing rate in the omeprazole group, but not in the nizatidine groups. Clinical features, such as sex, age, alcohol consumption, ulcer size, past history of upper gastrointestinal bleeding and duration of peptic ulcer history, did not collate with the healing rate. Patients with double-dose nizatidine did not show any benefits over those with a regular dose in this study. Adverse effects were minor, and there were no significant changes in biochemistry after therapy in these three groups of patients.

Adult↗