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Biomedical subjects

G H Chen

Publications and source records attributed to G H Chen.

At least 91 records · Page 5Linked to original sources
PubMed1996

Abnormal gastric emptying and Helicobacter pylori infection in patients with cirrhosis of the liver.

Thirty-seven patients aged 36-75 years with cirrhosis of the liver secondary to chronic hepatitis were included in the study. They were divided into three groups according to the modified Child's classification for cirrhotic severity, where A = good, B = fair and C = poor. In addition, the patients were divided according to the presence or absence of each of the following: ascites, splenomegaly and oesophageal varices. Radionuclide-labelled solid meals were used to evaluate gastric emptying and the 14C-urea breath test was used to detect Helicobacter pylori infection. Gastric emptying was represented by the gastric retention ratio of the solid meal at 90 min (RR90) and calculated using the following formula: the residual radioactivity within the region of interest (ROI) covering the whole stomach at 90 min divided by the initial radioactivity within the ROI at 0 min. We found that 75.7% (28/37) of the patients had abnormal gastric emptying and 45.9% (17/37) had H. pylori infection. No significant correlation was found between abnormal gastric emptying and H. pylori infection. There were no significant differences among the three groups regarding gastric emptying or H. pylori infection according to the modified Child's classification. However, the highest rates of abnormal gastric emptying and H. pylori infection were in patients in Child's class C. The differences in RR90 among patients with and without ascites, and patients with and without splenomegaly, were not significant (P > 0.05). However, there was a significant difference between the patients with and without oesophageal varices (P < 0.05). In addition, poor correlations (R2 < 0.01) were found between RR90 and serum levels of bilirubin and albumin.

Adult↗
PubMed1996

Gastric clearance of radiopaque markers in non-ulcer dyspepsia patients.

BACKGROUND: The use of radiopaque markers has been proposed as an easy, non-invasive method for measuring gastric emptying. In this study we intended to evaluate the effectiveness of this test in determining the gastric motor function in patients with non-ulcer dyspepsia. METHODS: Simultaneous recording of scintigraphic solid gastric emptying and gastric clearance of radiopaque markers were conducted in 65 non-ulcer dyspepsia patients. RESULTS: Forty-two patients (64.4%) showed abnormal gastric clearance of radiopaque markers, and 38 patients (58.5%) showed delayed solid gastric emptying. There was no correlation between delayed solid gastric emptying and abnormal gastric clearance of radiopaque markers (p > 0.05). Although the frequency of abnormal gastric clearance of radiopaque markers was higher than that of delayed solid gastric emptying (64.6% versus 58.5%), it was not statistically significant. CONCLUSIONS: On the basis of the results of our study, gastric clearance of radiopaque markers may be used as an easy, non-invasive screening test for the purpose of detecting gastric motor dysfunction. However, this test is not superior to scintigraphic gastric emptying studies.

Adolescent↗
PubMed1996

The effect of Helicobacter pylori infection on gastric emptying of digestible and indigestible solids in patients with nonulcer dyspepsia.

OBJECTIVE: There is no general agreement with regard to the effect of Helicobacter pylori infection on gastric emptying in patients with nonulcer dyspepsia. METHODS: We performed the 14C urea breath test as well as simultaneous recordings of scintigraphic gastic emptying and gastric clearance of radiopaque markers to determine the effect of Helicobacter pylori infection on gastric emptying of digestible and indigestible solids in nonulcer dyspepsia patients. RESULTS: Sixty patients, 30 males and 30 females, were enrolled in the study. There were 22 patients (36.7%) without and 38 patients (63.3%) with H. pylori infection. Twenty-four of the 60 patients (40%) showed normal and 36 patients (60%) showed delayed gastric emptying of digestible solids. In addition, 21 patients (35%) showed normal and 39 patients (63%) showed delayed gastric emptying of indigestible solids. There was no correlation between delayed gastric emptying of digestible and indigestible solids (p > 0.05, difference not significant). Although not statistically significant, the incidence of delayed indigestible solid emptying was higher than that of delayed digestible solid emptying (65% vs. 60%). Among different patterns of gastric emptying, no difference was noted between the patients with and without H. pylori infection. CONCLUSION: Delayed gastric emptying of indigestible solids is as common as delayed gastric emptying of digestible solids in nonulcer dyspepsia patients. The status of H. Pylori infection appeared not to influence the incidence of delayed gastric emptying of digestible and indigestible solids.

Adolescent↗
PubMed1996

Abnormal gastric emptying in patients with liver cirrhosis.

Twenty-eight patients (aged: 44-76 years) with liver cirrhosis secondary to chronic hepatitis were included in this study. None of the patients had a history of gastric surgery, diabetes, hypothyroidism, or neurological or collagen vascular disease. The patients were divided into groups based on the presence or absence of the following conditions: (1) ascites, (2) splenomegaly, (3) esophageal varices. Radionuclide labelled solid meals were used to evaluate gastric emptying (GE). GE was represented by the gastric retention ratio of the solid meal at 90 min (RR90), and calculated by the following formula: RR90 = residual radioactivity within the region of interest (ROI) covered the whole stomach at 90 min divided by the initial radioactivity within the ROI at 0 min. The RR90 values of the patients were compared with the RR90 values of 25 normal control volunteers. If the RR90 was more than two standard deviations (SD) above the mean of the control group (> 0.687), GE was defined as abnormal. The results showed 71% (20/ 28) of the cirrhotic patients had abnormal GE. Patients with ascites, splenomegaly, or esophageal varices had higher RR90 values than patients without ascites, splenomegaly or esophageal varices. The differences in RR90 among patients with and without ascites, and patients with and without splenomegaly, were not significant (P values > 0.05). However, there were significant differences among the 2 patient groups separated according to the presence or absence of esophageal varices (P values < 0.05). In addition, poor correlations (R square values < 0.01) were found for RR90 and serum values of bilirubin and albumin.

Adult↗
PubMed1996

[Gastric emptying in non-insulin dependent diabetic patients].

Disordered gastrointestinal motility is an often overlooked clinical problem. Delayed gastric emptying of solid and/or liquid meal in patients with both type 1 and type 2 diabetes mellitus occurs in approximately 50% of these patients. Gastric emptying time (GET) was studied in seventy four non-insulin dependent (type 2) diabetic out-patients by using radionuclide gamma-photography with Tc-99m phytate solid experimental meal. Thirty nine of them received Tc-99m phytate liquid test meal on the next day. Forty six normal healthy volunteers acted as controls. The results showed that solid GET in patients with type 2 diabetes mellitus was significantly delayed (149.44 +/- 64.0 min) as compared with that in the control group (88.7 +/- 14.2 min) (p < 0.001). Fifty three among these 74 diabetic patients had delayed solid GET, accounting for 71.6%. Only 5 of 39 (12.8%) diabetic patients showed delayed liquid GET (average 38.7 +/- 35.3 min; control 46.2 +/- 11.1 min). There were no differences in sugar control, duration of the disease, and upper gastrointestinal symptoms between patients with delayed GET and those with normal GET. We concluded that delayed gastric emptying is very common in patients with non-insulin dependent diabetes mellitus and which has no direct correlation to blood sugar control, duration of the disease, and upper gastrointestinal symptoms. Radionuclide solid gastric emptying test is a both safe (low radioactivity) and convenient (non-invasive) diagnostic tool in non-insulin dependent diabetic gastroparesis.

Adult↗
PubMed1996

Relationship between C14 urea breath test values and solid-phase gastric emptying time in non-ulcer dyspepsia patients.

BACKGROUND: Non-ulcer dyspepsia (NUD) is a poorly understood syndrome often found with endoscopic evidence of gastritis; Helicobacter pylori (Hp) is a common and important cause of gastritis. In the recent literature, gastric hypomotility is thought to be a cause of NUD. Thus, this investigation studied the relationship between Hp and delayed gastric emptying in NUD patients. METHODS: Using a radionuclide-labelled solid meal to calculate gastric emptying time (GET) of 78 NUD patients. The carbon-14 urea breath test (C14 UBT) was used to quantitate Hp infection. RESULTS: The prevalence of Hp infection in patients with NUD reached 59%. There was a strong association of Hp infection with advanced age (p = 0.0091). There was no significant difference between solid-phase GET and C14 UBT values among three different age groups (young, middle, old) of NUD patients. There was no difference among sex, age, body weight and solid-phase GET between Hp-positive and Hp-negative NUD patients. However the solid-phase GET was significantly prolonged in patients with NUD, compared with the controls. CONCLUSIONS: Solid-phase GET is not correlated with the C14 UBT values, and Hp gastric colonization does not account for dyspeptic syndrome in NUD patients.

Adult↗
PubMed1996

Cytomegalovirus colitis in an immunocompetent old woman successfully treated with ganciclovir: a case report.

Cytomegalovirus (CMV) diseases occur almost exclusively in the immunocompromised hosts. Persons most commonly affected are patients with acquired immunodeficiency syndrome (AIDS). On rare occasions, however, CMV diseases can be seen in apparently immunocompetent persons. A CMV colitis in a 68-year old immunocompetent woman presenting with watery diarrhea, malaise, and body weight loss of about 5 kg over a three week period is reported. Colonoscopy and mucosal biopsy revealed CMV colitis involving the sigmoid colon. Treatment for two weeks with ganciclovir (10 gm/kg/day I.V. in 2 divided doses) resulted in resolution of colitis and clinical symptoms without any noticeable side-effects. There was no relapse of infection by six months of follow-up. The possibility of CMV colitis should be considered in any elderly person with watery diarrhea, general debilitation, marked body weight loss and with negative stool cultures. CMV colitis may be more frequent than is usually believed. It has a favorable response to ganciclovir without further relapse after the successful treatment in patients with normal immune function.

Aged↗
PubMed1996

Evaluation of lung ventilation and alveolar permeability in cirrhosis.

UNLABELLED: This study sought to evaluate lung ventilation and alveolar permeability (AP) in patients with cirrhosis of the liver. METHODS: Pulmonary function in 29 patients with cirrhosis was measured by 99mTc-DTPA aerosol inhalation lung scintigraphy, using commercial lung radio-aerosol delivery units. Equilibrium lung ventilation images were visually interpreted according to the presence or absence of inhomogeneous distribution, inverted base-to-apex gradient and segmental defects. Degree of AP damage to the upper, middle, lower and total right lung was expressed as the slopes of the time-activity curves from dynamic lung images. The patients were classified into three groups, according to cirrhotic severity, using the modified Child's classification (A = good; B = fair; C = poor). Twelve healthy nonsmokers (2 women, 10 men; 42-75 yr old) formed the control group, and all had normal chest radiographic and pulmonary function test results. RESULTS: None of the 29 patients had significantly abnormal lung ventilation findings, but 13 had reduced lung ventilation in the basilar lung zone. The incidence of lung ventilation abnormalities was 20% (3 of 15), 50% (3 of 6) and 88% (7 of 8) in patients with nil, slight-to-moderate and moderate-to-severe ascites, respectively (p < 0.05 for nil versus moderate-to-severe ascites). The AP studies showed higher time-activity curve slopes for patients with cirrhosis than for normal control subjects. The slopes for the right total lung showed no significant differences among the three groups; however, those for right upper and right lower lung showed significant differences between some subgroups. In addition, albumin and bilirubin levels showed no significant correlation with slope values in cirrhotic patients. CONCLUSION: Although lung ventilation is normal in most patients with cirrhosis of the liver (16 [55%] of 29 in the present study), the disease can predispose patients to AP damage; however, the degree of damage is not related to cirrhotic severity.

Adult↗
PubMed1996

Squamous papilloma of the esophagus.

BACKGROUND: Squamous papilloma of the esophagus (SPE) is a rare lesion, with a prevalence of 0.01% to 0.04%. This study was to assess the incidence, symptoms, signs and prognosis of squamous papilloma of the esophagus. METHODS: From October 1981 to October 1994, 124,000 patients at our hospital were examined with panendoscopy; 9 (0.0073%) subjects were histologically proved to have squamous papilloma of the esophagus. RESULTS: They included 4 males and 5 females, aged 60.8 +/- 9.7 years, ranging from 49 to 78 years old. These tumor locations were seven in the lower, one in the middle and one in the upper portion of the esophagus; sizes were not larger than 5 mm. Most of them were single (seven of nine) and sessile (eight of nine). Three of them were followed up with panendoscopy and six of them were followed up through clinical symptoms. The longest follow-up period were 11 years. The mean following time was 2.2 +/- 3.6 years. CONCLUSIONS: All of the patients are alive, and none has malignancy in the SPE. It is suggested that squamous papilloma of the esophagus may have a benign clinical course. Symptoms and signs are thought to be associated with gastroesophageal reflux or peptic ulcer diseases, and not to be related to the squamous cell papilloma itself.

Aged↗
PubMed1995

Down-regulation of the afferent phase of T cell-mediated pulmonary inflammation and immunity by a high melanin-producing strain of Cryptococcus neoformans.

The interaction(s) between cryptococcal virulence factors and leukocytes involved in generating protective cell-mediated immunity is not well defined. Intratracheal inoculation of Cryptococcus neoformans strain 52 induced a vigorous T cell-mediated pulmonary inflammatory response that controlled the growth of the organism. In contrast, strain 145 induced a pulmonary inflammatory response that was delayed in onset, slower to develop, and ineffective in controlling the infection. In addition, the expansion of cryptococcus-specific lymphocytes in the pulmonary lymph nodes and titer of specific Abs in the serum of strain 145-infected mice were both diminished markedly. Of the known cryptococcal virulence factors, these two strains differed only in melanin production (52-low and 145-high). Heat-killed strain 145 cryptococci (HKC-145) that had been rendered melanin-negative induced TNF-alpha production by alveolar macrophages in vitro and stimulated vigorous cryptococcus-specific lymphoproliferation. In contrast, high melanin-containing HKC-145 inhibited TNF-alpha production and lymphoproliferation. In vivo, mice infected with melanin low strain 52, but not melanin high strain 145, had elevated levels of TNF-alpha in the bronchoalveolar lavage fluid. Mice co-infected with strains 145 and 52 generated a pulmonary inflammatory response resulting in increased long-term survival. Taken together, these studies demonstrate that melanin does not protect cryptococci from being eliminated in vivo by recruited, activated effector cells; but melanin can inhibit the recognition of the organism by host defenses, thereby down-regulating the afferent phase of T cell-mediated immunity, e.g., TNF-alpha production and lymphoproliferation.

Animals↗
PubMed1995

Increased accuracy of the carbon-14 D-xylose breath test in detecting small-intestinal bacterial overgrowth by correction with the gastric emptying rate.

To date, there is no general agreement as to which test is to be preferred for the diagnosis of small-intestinal bacterial overgrowth. The 1-g carbon-14 D-xylose breath test has been proposed as a very sensitive and specific test for the diagnosis of bacterial overgrowth. However, in patients with severe gastrointestinal motor dysfunction, the lack of consistent delivery of 14C-D-xylose to the region of bacterial contamination may result in a "negative" result. The aim of this study was to determine whether the accuracy of 14C-D-xylose breath test for detecting bacterial overgrowth can be increased by correction with the gastric emptying rate of 14C-D-xylose. Ten culture-positive patients and ten culture-negative controls were included in the study. Small-intestinal aspirates for bacteriological culture were obtained endoscopically. A liquid-phase gastric emptying study was performed simultaneously to assess the amount of 14C-D-xylose that entered the small intestine. The results of the percentage of expired 14CO2 at 30 min were corrected with the amount of 14C-D-xylose that entered the small intestine. There were six patients in the culture-positive group with a 14CO2 concentration above the normal limit. Three out of four patients with initially negative results using the uncorrected method proved to be positive after correction. All these three patients had prolonged gastric emptying of 14C-D-xylose. When compared with cultures of small-intestine aspirates, the sensitivity and specificity of the uncorrected 14C-D-xylose breath test were 60% and 90%, respectively. In contrast, the sensitivity and specificity of the corrected 14C-D-xylose breath test improved to 90% and 100%, respectively. In conclusion, using the gastric emptying rate of 14C-D-xylose as a correcting factor, we found a higher sensitivity and specificity for the 14C-D-xylose breath test in the detection of small-intestinal bacterial overgrowth than were achieved with the conventional method.

Adult↗
PubMed1995

The relationship between Helicobacter pylori infection and gastric emptying in patients with non-insulin-dependent diabetes mellitus.

Forty-four patients with non-insulin-dependent diabetes mellitus (NIDDM) were included in this study. Radionuclide-labelled solid meals were used to calculate gastric emptying times (GETs). The carbon-14 urea breath test (14C-UBT) was used to diagnose Helicobacter pylori (HP) infection. The patients were separated into groups according to the following two criteria: (1) HP infection was diagnosed on the basis of a 14C-UBT value of > or = 1.5; (2) the GET was defined as abnormal when it was > or = 117.1 min. The results showed that 61% (27/44) of the NIDDM patients had an HP infection, and 59% (26/44) had an abnormal GET. The incidence of abnormal GET in positive 14C-UBT patients (62%) was higher than that in negative 14C-UBT patients (56%). Similarly, the incidence of positive 14C-UBT in abnormal GET cases (62%) was higher than that in normal GET cases (56%). However, according to chi-square tests the differences were not significant. In conclusion, no significant relationship between HP infection and GET was found in patients with NIDDM.

Aged↗
PubMed1995

The effect of coffee on gastric emptying.

The effect of coffee on gastric emptying was addressed in a scintigraphic liquid-phase gastric emptying study in patients with non-ulcer dyspepsia. Ninety-three subjects (56 males, 37 females; mean age 40 years, range 17-77 years) diagnosed as having non-ulcer dyspepsia were enrolled in the study. The baseline study was to drink 500 ml of 5% glucose water and the coffee study was to drink 500 ml of 5% glucose water containing 4 g of regular instant coffee. The two studies were performed on separate days. Fifteen of the 93 subjects were chosen at random to undergo repeated coffee studies for evaluation of reproducibility. Overall the 93 subjects showed accelerated gastric emptying, as measured by half emptying time (T1/2) with coffee compared with baseline (35.7 +/- 10.5 vs 45.0 +/- 23.1 min, P < 0.001). However, 68 (73.2%) subjects showed accelerated emptying (-14.8 +/- 19.5 min), while 25 (26.8%) subjects showed delayed emptying (5.9 +/- 4.5 min) after ingestion of coffee. There was no significant difference in the change in gastric emptying with coffee in duplicate measurements from the 15 subjects who had two coffee studies (P = 0.082). We conclude that coffee accelerates liquid-phase gastric emptying in the majority of patients with non-ulcer dyspepsia.

Adult↗
PubMed1995

Delayed gastric emptying does not predispose to Helicobacter pylori infection in non-ulcer dyspepsia patients.

Non-ulcer dyspepsia is a common disorder in clinical practice. The pathogenesis and predisposing factors that lead to the development of Helicobacter pylori infection are still unclear. The aim of the present study was to evaluate the prevalence of H. pylori infection in non-ulcer dyspepsia patients with delayed gastric emptying and those with normal gastric emptying, and to determine if delayed gastric emptying predisposes to H. pylori infection. A total of 70 patients (29 males, 41 females) aged 18-59 years (mean +/- S.D. 40.5 +/- 11.2 years) took part in the study. A solid-phase scintigraphic gastric emptying study and 14C urea breath test were performed on each patient. There was no statistically significant difference in age between those patients with and without delayed gastric emptying (40.8 +/- 11.9 vs 40.4 +/- 10.5 years), or between those with and without H. pylori infection (40.5 +/- 12.6 vs 40.5 +/- 9.8 years). Of the 70 patients, 45 (64.3%) had delayed gastric emptying and 25 (35.7%) had normal gastric emptying. The overall incidence of H. pylori infection was 58.6%. The incidence of H. pylori infection among patients with delayed gastric emptying was 60% (27/45 patients) and among patients with normal gastric emptying 56% (14/25) patients). The incidence of H. pylori infection in the two groups was not significantly different. The incidence of H. pylori infection in the non-ulcer dyspepsia patients in this study was similar to that of age-matched asymptomatic volunteers in Taiwan. In conclusion, based on the results of this study, delayed gastric emptying does not lead to a predisposition to H. pylori infection in non-ulcer dyspepsia patients.

Adolescent↗
PubMed1995

Regulation of rat pulmonary dendritic cell immunostimulatory activity by alveolar epithelial cell-derived granulocyte macrophage colony-stimulating factor.

The presentation and recognition of foreign antigen is the critical initial event in the development of local immunity. In the lung, antigen-presenting cell activity is largely attributable to pulmonary dendritic cells (DC) that are distributed along the airways and throughout the pulmonary interstitium in close proximity to overlying alveolar epithelial cells. To test the hypothesis that DC immunostimulatory activity might be locally regulated by overlying alveolar epithelial cells, we evaluated the ability of rat type II alveolar epithelial cells to influence the capacity of purified rat pulmonary DC to stimulate T-cell proliferation in an allogeneic, mixed leukocyte reaction. We found that alveolar epithelial cells greatly enhanced the ability of dendritic cells to induce T-cell proliferation. This effect on DC immunostimulatory activity was mediated by a soluble factor preferentially secreted from the basolateral epithelial cell surface. Alveolar epithelial cultures were found to express mRNA for granulocyte macrophage colony-stimulating factor (GM-CSF), and blocking antibodies against GM-CSF partially neutralized the effect of epithelial cell-conditioned media on DC stimulatory activity, indicating that the effect was due at least in part to alveolar epithelial cell-derived GM-CSF. Through the polar secretion of GM-CSF, alveolar epithelial cells may play an important role in creating distinct immunologic environments within the lung.

Animals↗