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Biomedical subjects

G H Chen

Publications and source records attributed to G H Chen.

At least 73 records · Page 4Linked to original sources
PubMed1998

Gastric dysrhythmia in uremic patients on maintenance hemodialysis.

BACKGROUND: Dyspeptic symptoms are common in uremic patients receiving hemodialysis. Investigators have placed emphasis on the changes in histopathology and physiology of the gastrointestinal tract. But not much data about the gastric myoelectric activity are available. The aim of this study was to assess gastric myoelectric activity in uremic patients undergoing hemodialysis. METHODS: Fifty-eight subjects were enrolled. They were assigned to: group I, uremic patients undergoing hemodialysis with dyspeptic complaints (n = 20); group II, non-uremic patients with matched dyspeptic complaints (n = 20); and group III, healthy volunteers without dyspeptic complaints (n = 18). Gastric myoelectric activity was measured with abdominal surface electrodes in each person. Patients in group I were measured twice, before (group Ia) and after (group Ib) hemodialysis. The data were compared between the groups. RESULTS: In the prehemodialysis period there was a significantly lower percentage of normal slow-wave frequency when compared with group III (fasting, 66.54%+/-5.39% versus 84.58%+/-3.63%; P < 0.005; fed, 72.25%+/-4.16% versus 89.06%+/-2.57%; P < 0.01). In the post-hemodialysis period the difference was even more profound (fasting, 46.52%+/-4.26% versus 84.58%+/-3.63%; P < 0.001; fed, 51.49%+/-6.89% versus 89.06%+/-2.57%; P < 0.005). Yet, when compared with group II, a significant difference existed only in the post-hemodialysis period (fasting, 46.52%+/-4.26% versus 67.30%+/-3.46%; P<0.001; fed, 51.49%+/-6.89% versus 70.41%+/-4.39%; P < 0.01). Another finding is that hemodialysis decreased the gastric myoelectric activity after hemodialysis (fasting, 66.54%+/-5.39% versus 46.52%+/-4.26%; P < 0.001; fed, 72.25%+/-4.16% versus 51.49%+/-6.89%; P < 0.005). CONCLUSIONS: Uremic patients undergoing hemodialysis have impaired gastric myoelectric activity. Interestingly, hemodialysis seems to cause deterioration in gastric myoelectric activity.

Adult↗
PubMed1998

Salivary function in patients with reflux esophagitis: effect of cisapride.

UNLABELLED: Saliva plays an important role in esophageal acid clearance. Reduction in salivary function has been considered in the pathogenesis of reflux esophagitis. Cisapride, a prokinetic agent, has been reported effective for treating mild-to-moderate grade gastroesophageal reflux disease. Some studies have shown that cisapride increases saliva volume and acid-buffering capacity. The aim of this study was to evaluate the effect of cisapride on salivary gland function by means of dynamic salivary scintigraphy. METHODS: Fifty-five patients with endoscopic reflux esophagitis (Savary-Miller Grades I-II) were enrolled in this study. In Group 1 (n = 29), patients were evaluated during the fasting state, both before and after cisapride treatment (5 mg, 3 times/day, before meals, for 2 wk). In Group 2 (n = 26), patients were evaluated during the postprandial state, both before and after cisapride treatment. Uptake ratio (UR) and excretion ratio (ER) of the salivary gland in each group were compared using the paired Student's t-test. RESULTS: In Group 1, no significant differences were found in UR or ER after cisapride treatment. However, in Group 2, ER increased significantly after treatment (p < 0.01), but UR did not show any significant change. CONCLUSION: Cisapride can increase the secretion function of salivary glands during the postprandial phase but not the fasting phase.

Cisapride↗
PubMed1998

Intraluminal mucin pool in mucinous gastric adenocarcinoma: a case report.

Mucinous gastric carcinoma is a rare pathologic subtype of gastric adenocarcinoma. Whether the mucin behaves aggressively as in mucinous colorectal carcinoma is still controversial. Most mucinous gastric carcinomas are diagnosed from surgical specimens. The mucinous gastric carcinoma in this case report was discovered preoperatively according to its characteristic presentation. An upper gastrointestinal endoscopic examination showed a round protruding tumor of greater than 4 cm in size on the mid-body of the stomach; it had an uneven, friable and shiny surface. The surface was coated with a sticky layer of mucin-like substance, which persisted even after the aspiration of the gastric juice. Endoscopic ultrasonography (EUS) revealed a large heterogeneous hyperechoic tumor mass, originating from the mucosal and submucosal layers, on the body of the stomach. The mass was covered with a thick layer of hypoechoic amorphous substance. Hence, a mucin-producing tumor was suspected. Subsequent surgical biopsy proved the mass to be a moderately differentiated mucinous adenocarcinoma. This case illustrates the first endoscopic ultrasonographic report of an intraluminal mucin pool as a hypoechoic substance, which is quite different from the hyperechoic presentation of intramural mucin lakes. In preoperative evaluation, EUS is not only important for determining the depth of tumor invasion, but it is also useful in differentiating mucinous gastric carcinoma from nonmucinous gastric carcinoma.

Adenocarcinoma, Mucinous↗
PubMed1997

Enteric-coated peppermint-oil capsules in the treatment of irritable bowel syndrome: a prospective, randomized trial.

To determine the efficacy and tolerability of an enteric-coated peppermint-oil formulation (Colpermin), we conducted a prospective, randomized, double-blind, placebo-controlled clinical study in 110 outpatients (66 men/44 women; 18-70 years of age) with symptoms of irritable bowel syndrome. Patients took one capsule (Colpermin or placebo) three to four times daily, 15-30 min before meals, for 1 month. Fifty-two patients on Colpermin and 49 on placebo completed the study. Forty-one patients on Colpermin (79%) experienced an alleviation of the severity of abdominal pain (29 were pain-free); 43 (83%) had less abdominal distension, 43 (83%) had reduced stool frequency, 38 (73%) had fewer borborygmi, and 41 (79%) less flatulence. Corresponding figures for the placebo group were: 21 patients (43%) with reduced pain (4 were pain-free), 14 (29%) with reduced distension, 16 (32%) with reduced stool frequency, 15 (31%) with fewer borborygmi, and 11 (22%) with less flatulence. Symptom improvements after Colpermin were significantly better than after placebo (P < 0.05; Mann-Whitney U-test). One patient on Colpermin experienced heartburn (because of chewing the capsules) and one developed a mild transient skin rash. There were no significant changes in liver function test results. Thus, in this trial, Colpermin was effective and well tolerated.

Adolescent↗
PubMed1997

Nitric oxide is required for effective innate immunity against Klebsiella pneumoniae.

Nitric oxide (NO) has been associated with protection against various parasitic and viral infections and may play a similar role in bacterial infections. We studied the role of NO in host defense against Klebsiella pneumoniae infection in the lung. Initial studies demonstrated a time-dependent increase in NO production of the lungs of CBA/J mice following the intratracheal administration of K. pneumoniae (7 x 10(2) CFU). To assess the role of NO in Klebsiella pneumonia, mice were treated intraperitoneally with either L-NAME (N-omega-nitro-L-arginine methylester), a competitive inhibitor of NO synthesis, or D-NAME, an inert enantiomer. The treatment of Klebsiella-infected mice with L-NAME resulted in a 10- and 46-fold increase in K. pneumoniae CFU in lungs and blood, respectively, at 48 h post-K. pneumoniae inoculation compared to treatment of mice with D-NAME. In addition, a greater-than-twofold increase in mortality was evident in L-NAME-treated mice compared to the mortality in control animals. No significant difference in bronchoalveolar lavage inflammatory cell profiles was noted between L-NAME- and D-NAME-treated mice with Klebsiella pneumonia. Interestingly, increased levels of tumor necrosis factor, gamma interferon, macrophage inflammatory protein 1alpha (MIP-1alpha), and MIP-2 mRNA and protein were noted in infected mice treated with L-NAME compared to the levels in mice treated with D-NAME. Importantly, the in vitro incubation of murine alveolar macrophages with L-NAME, but not with D-NAME, resulted in a significant impairment in both the phagocytosis and killing of K. pneumoniae. In total, these results suggest that NO plays a critical role in antibacterial host defense against K. pneumoniae, in part by regulating macrophage phagocytic and microbicidal activity.

Animals↗
PubMed1997

Comprehensive gastric emptying study for type-II diabetes mellitus dyspeptic patients.

BACKGROUND: Gastrointestinal symptoms without demonstrable lesions in the upper gastrointestinal tract are common in diabetic patients. Scintigraphic liquid- and solid-phase gastric emptying studies and gastric emptying of indigestible particles were performed to determine the gastric emptying function in type-II diabetes mellitus patients with dyspepsia. METHODS: Twenty type-II diabetic patients with symptoms suggestive of delayed gastric emptying were included. A gelatin capsule containing 10 rod-shaped radiopaque markers was ingested, along with the solid-phase test meal, to assess the emptying of indigestible particles. Scintigraphic liquid-phase gastric emptying studies were performed on a separate day. RESULTS: There were 7 patients (35%) with delayed liquid-phase gastric emptying, 14 patients (70%) with delayed solid-phase gastric emptying, and 14 patients (70%) with abnormal gastric emptying of indigestible particles. There were only three patients (15%) with normal gastric emptying of both the liquid and solid phase. Furthermore, only one patient showed normal result in all three gastric emptying studies. CONCLUSIONS: For determining abnormalities in gastric emptying function for type-II diabetic dyspepsia patients, comprehensive gastric emptying studies, including scintigraphic liquid- and solid-phase gastric emptying studies and gastric emptying of indigestible particles, are most helpful.

Aged↗
PubMed1997

The incidence of reflux esophagitis among the Chinese.

OBJECTIVES: Very few epidemiological data on reflux esophagitis in Chinese are available in the literature. METHODS: To evaluate the incidence of reflux esophagitis, upper gastrointestinal endoscopies were performed on 2044 patients (male 1266, female 778; age range 16-82 yr) during a 6-month period. RESULTS: The overall incidence of reflux esophagitis was 5%, and most of the patients (86.3%) had a mild grade of esophagitis. Hiatal hernia was found in 44 patients (2.2%); those patients were significantly older than those without hiatal hernia (60.3 +/- 10.8 vs. 49.4 +/- 12.1 yr, p < 0.05). Patients with symptoms suggesting gastroesophageal reflux (acid regurgitation, heartburn, and belching) had higher incidence of esophagitis (22.9%, 22.5%, and 24.7%, respectively). The body mass index was significantly higher in patients with esophagitis than in those without esophagitis (25.7 +/- 3.1 vs. 24.0 +/- 3.6, p < 0.05). The male:female ratio for esophagitis was 5.6:1. No esophagitis was found in patients who were less than 21 yr old. However, there was a difference in age group distribution for the incidence of esophagitis. The habit of coffee or tea drinking does not contribute to the development of esophagitis. CONCLUSIONS: Based on the results of this study, the incidence of endoscopic reflux esophagitis among the Chinese is 5%, which is lower than in Western countries.

Adolescent↗
PubMed1997

Correlation between patterns of antral contractility and gastric emptying of radiopaque markers.

OBJECTIVES: Gastric clearance of radiopaque markers (ROMs) has been proposed as an easy and noninvasive technique for assessment of gastric emptying. This study was conducted to evaluate the role of antral obliterating contractions in gastric emptying of ROMs in healthy volunteers. METHODS: Fifteen healthy volunteers, 12 males and three females, aged 21-38 yr, were enrolled in this study. Simultaneous recording of scintigraphic solid phase gastric emptying, gastric clearance of ROMs, and gastric manometry were performed after an overnight fast. The data of scintigraphic solid phase gastric emptying were expressed by half-emptying time (t1/2). The ROMs remaining in the stomach were counted fluoroscopically 2.5 and 4.5 h after the test meal. The time for the appearance of antral obliterating contractions after the meal was calculated. RESULTS: Six subjects (40%) passed all 10 ROMs after 4.5 h of recording. Among these six subjects, five had antral obliterating contractions 190-251 min (mean 232.2 +/- 24.3 min) after the test meal. There was no significant difference in t1/2 between subjects with or without antral obliterating contractions within the 4.5 h of recording. CONCLUSIONS: There was a considerable intersubject variation in the time of first antral obliterating contraction after the test meal. In the healthy volunteers, all ROMs were passed when there was a postprandial antral obliterating contraction. However, some of the ROMs still passed from the stomach in the absence of antral obliterating contractions.

Adult↗
PubMed1997

Ambulatory 24-hour esophageal manometry and pH-metry in patients with noncardiac chest pain, but no reflux symptoms.

The aim of this study is to determine the diagnostic value of 24-hour ambulatory esophageal manometry and pH-metry for patients with noncardiac chest pain (NCCP), but no reflux symptoms. Twenty-four hour ambulatory esophageal manometry and pH-metry was performed on 34 patients with NCCP, but no reflux symptoms. The pressure transducers were located 3, 8, and 13 cm above the lower esophageal sphincter (LES) and the pH probes were located 5 and 20 cm above the LES. An event marker was triggered by the patient for chest pain. Only 17 patients (50%) had at least one pain episode (total 81 episodes, range 1-19 episodes per person) during a 24-hour recording. Twenty-one chest pain episodes (26%) occurred during abnormal motility, whereas 4 episodes (5%) were associated with pH < 4, and 10 episodes (12%) had both abnormalities. The majority of chest pain episodes, 46 out of 81 events (57%), did not have any association with motility or pH abnormalities. Five of 7 patients (71%) with reflux-related chest pain and 8 of 11 patients (73%) with dysmotility-related chest pain had symptom association probability > 95%, indicating a significant association between chest pain and esophageal dysfunction. Our conclusion is that ambulatory esophageal manometry and pH-metry is a useful tool in the evaluation of NCCP, but only a few additional patients with reflux-related chest pain could be found in patients without reflux symptoms.

Adult↗
PubMed1997

[The effect of the dry heat sterilization on vaseline gauze].

When taking dry heat sterilization on vaseline gauze, it must be strictly control sterile temperature and time. The result of this test indicated that sterilization can be made either with a temperature of 160 degrees and lasting 90 minutes or with a temperature of 150 degrees and lasting 120 minutes. But the box can not be opened at once and use the steriled vaseline gauze unless its temperature is naturally lowered. If it is obliged to be opened, the vaseline gauze can be recontaminated. Attention must be paid to both the cleaning of sample background and regularized manipulation, otherwise it may cause false positive and disturb the result of surveillance.

Bandages↗
PubMed1996

Urokinase is required for the pulmonary inflammatory response to Cryptococcus neoformans. A murine transgenic model.

Urokinase (uPA) is hypothesized to provide proteolytic activity enabling inflammatory cells to traverse tissues during recruitment, and it is implicated as a cytokine modulator. Definitive evaluation of these hypotheses in vivo has previously been impossible because uPA could not completely and irreversibly be eliminated. This limitation has been overcome through the development of uPA-deficient transgenic mice (uPA-/-). Using these mice, we evaluated the importance of uPA in the pulmonary inflammatory response to Cryptococcus neoformans (strain 52D). C. neoformans was inoculated into uPA-/- and control mice (uPA+/+), and cell recruitment to the lungs was quantitated. The number of CFU in lung, spleen and brain was determined to assess clearance, and survival curves were generated. By day 21 after inoculation, uPA-/- mice had markedly fewer pulmonary inflammatory (CD45+), CD4+, and CD11b/CD18+ cells compared with uPA+/+ controls (P<0.0007); pulmonary CFUs in the uPA-/- mice continued to increase, whereas CFUs diminished in uPA+/+ mice(P<0.005). In survival studies, only 3/19 uPA+/+ mice died, whereas 15/19 uPA-/- mice died (p<0.001). We have demonstrated that uPA is required for a pulmonary inflammatory response to C. neoformans. Lack of uPA results in inadequate cellular recruitment, uncontrolled infection, and death.

Animals↗
PubMed1996

Granulocyte-macrophage colony-stimulating factor overrides the immunosuppressive function of corticosteroids on rat pulmonary dendritic cells.

Pulmonary dendritic cells (DC) are present in extremely small numbers, but they are the most potent antigen-presenting cells in the lungs. Pure populations of DC can be isolated from the lung following collagen digestion, Percoll gradient centrifugation, removal of phagocytic cells and flow cytometric sorting for cells which exhibit high levels of surface major histocompatibility complex (MHC) class II molecules. Exogenous GM-CSF enhances this immunostimulatory capacity of the pulmonary DC. Soluble factors produced by type II airway epithelial cells and interstitial macrophages also enhance the immunostimulating capacity of pulmonary DC while alveolar macrophages suppress it. Thus, the function of DC may be regulated by locally produced cytokines. Corticosteroids are widely used as immunosuppressive agents in pharmacotherapy. While these agents are known to inhibit T cell proliferation and macrophage activation, their effects on DC are not known. We found that dexamethasone (Dex) pretreatment resulted in about a 50% reduction in the immunostimulatory capacity of rat pulmonary DC. This was associated with downregulation of MHC class II (Ia) expression. Dex-induced suppression of DC function could be restored with GM-CSF. We conclude that corticosteroids downregulate antigen-presenting capacity by direct suppression of pulmonary DC. This immunosuppressive effect of corticosteroids on DC may, however, be abrogated by exogenous GM-CSF. Corticosteroids and GM-CSF are therapeutic agents with potent direct immunomodulating effects on DC.

Adrenal Cortex Hormones↗
PubMed1996

Discrepant pattern of solid and liquid gastric emptying in Chinese patients with type II diabetes mellitus.

While abnormal gastric emptying has been widely reported in patients with diabetes, its clinical relevance is still uncertain. We conducted scintigraphic gastric emptying studies in patients with Type II diabetes mellitus who had symptoms suggestive of delayed gastric emptying in an attempt to evaluate the incidence of abnormal gastric emptying and to assess the clinical parameters of the different patterns of gastric emptying. Seventy male diabetic patients were included in the study. The patients were divided into four groups according to the results of liquid and solid gastric emptying: group 1, normal liquid and solid emptying (n = 22); group 2, normal liquid but delayed solid emptying (n = 30); group 3, delayed liquid but normal solid emptying (n = 7); group 4, delayed liquid and solid gastric emptying (n = 11). To assess clinical significance, we compared duration of disease, status of blood sugar control, presence or absence of vascular complications and of peripheral neuropathy among the four groups. Of the 70 patients, 18 (25.7%) showed delayed liquid gastric emptying and 41 (58.6%) delayed solid gastric emptying. There were no significant differences in the clinical parameters of the four groups, except that patients with good sugar control were likely to have normal liquid gastric emptying. Based on the results of this study, delayed solid gastric emptying is more common than liquid gastric emptying in symptomatic Type II diabetes mellitus patients. Of the different patterns of gastric emptying, delayed liquid gastric emptying with normal solid gastric emptying is the most unusual. For Type II diabetic patients with symptoms suggestive of delayed gastric emptying, both liquid and solid gastric emptying studies should be performed.

Aged↗