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Biomedical subjects

H C Lin

Publications and source records attributed to H C Lin.

At least 91 records · Page 5Linked to original sources
PubMed2000

Recurrence of esophageal varices following endoscopic treatment and its impact on rebleeding: comparison of sclerotherapy and ligation.

BACKGROUND/AIMS: Endoscopic variceal ligation is superior to sclerotherapy because of its lower rebleeding and complication rates. However, ligation is not without drawbacks due to a higher tendency to variceal recurrence. We conducted a randomized cohort study to delineate the long-term history of variceal recurrence following ligation and sclerotherapy, and to clarify the impact of recurrence on rebleeding and on the consumption of endoscopic treatment resources. METHODS: Two hundred cirrhotic patients with esophageal variceal bleeding were randomized to undergo maintenance endoscopic variceal sclerotherapy or ligation. RESULTS: One hundred and forty-one patients achieved variceal eradication and were regularly followed up for 2.2 to 6.7 (mean: 5.1 +/- 1.2) years. The demographic data, hepatic reserve, bleeding severity, and endoscopic features of both sclerotherapy (n=70) and ligation (n=71) showed no difference. Forty (57.1%) patients who underwent sclerotherapy experienced 58 recurrences of esophageal varices, in contrast to the 46 (64.8%) patients who underwent ligation and experienced 81 episodes of recurrence. Kaplan-Meier analysis showed that within 2 years variceal recurrence was more frequent for ligation than sclerotherapy, and the difference decreased thereafter. Multiple recurrence appeared more common with ligation (1/2/3/4/5 episodes of recurrence: 46/23/8/3/1 vs. 40/14/3/1/0, p=0.08). On multifactorial analysis, the endoscopic treatment method and red wale markings were the two factors determining variceal recurrence. Rebleeding from recurrent esophageal varices was unusual and showed no difference between the two groups (7/58 vs. 6/81, p>0.05). Rebleeding from gastric varices was more common after eradication by sclerotherapy (7/19 vs. 1/16, p=0.085) than by ligation. The number of sessions required for eradication of recurrent varices was no different between the two groups. CONCLUSIONS: Early recurrence and multiple recurrence of esophageal varices are more likely in patients undergoing endoscopic ligation, compared to sclerotherapy; however, the recurrence did not lead to a higher risk of rebleeding or require more endoscopic treatment.

Aged↗
PubMed2000

Release of distal gut peptide YY (PYY) by fat in proximal gut depends on CCK.

We tested the hypothesis that the release of PYY by fat confined to the proximal small intestine is dependent on CCK. Using a multi-fistulated model, plasma PYY levels were compared in 6 dogs after 60 mM oleate was perfused into the proximal one-half of the small intestine following i.v. administration of saline or devazepide, a CCK-A antagonist. Plasma PYY increased with fat (P < 0. 05), but plasma PYY level was lower following devazepide at 60 min and 90 min (P < 0.05). We conclude that CCK serves as a foregut signal linking fat in the proximal gut with the release of distal gut PYY.

Animals↗
PubMed2000

Evaluation of gallbladder motility in patients with liver cirrhosis: relationship to gallstone formation.

To investigate the postprandial gallbladder motility, including emptying and refilling, in cirrhotic patients and to evaluate the relationship to the presence of gallstones and various humoral mediators, 82 patients with liver cirrhosis and 40 age- and sex-matched healthy subjects were enrolled into this study. Postprandial gallbladder volumes were measured with ultrasonography every 15 min for 2 hr. Plasma levels of estradiol, testosterone, substance P, and nitrate/nitrite were also measured. Cirrhotic patients showed a higher prevalence of gallstones than healthy subjects (41% vs 15%, P = 0.003), and the prevalence increased with the progression of liver cirrhosis (Child-Pugh class A: 26%, B: 44%, and C: 65%, P = 0.02). Plasma levels of estradiol, testosterone, and substance P, and nitrate/nitrite and estradiol/testosterone ratios were not different between cirrhotic patients with and without gallstones. However, postprandial refilling of the gallbladders was significantly impaired in patients with cirrhosis, especially in those combined with gallstones. There was no significant difference in the postprandial gallbladder motility between cirrhotic patients with and without elevated plasma levels of estradiol, testosterone, and substance P and nitrate/nitrite, and estradiol/testosterone ratios. Gallstones were common in patients with liver cirrhosis and the prevalence increased with the progression of liver diseases. Sex hormones, substance P, and nitrate/nitrite did not play major roles in the formation of gallstones in cirrhotic patients. Refilling of the gallbladder was significantly impaired in patients with liver cirrhosis, especially in those with gallstones, and may play an important role in the pathogenesis of gallstones.

Aged↗
PubMed2000

Comparison of PCR-RFLP, ribotyping and ERIC-PCR for typing Bacillus anthracis and Bacillus cereus strains.

PCR-RFLP analysis of the vrrA gene and cerAB gene was used to investigate the genomic diversity in 21 strains of Bacillus anthracis and 28 strains of Bacillus cereus, and was compared with results obtained by ribotyping and enterobacterial repetitive intergenic consensus-PCR (ERIC-PCR) analysis. VrrA-typing divided the B. anthracis into four groups. Except for one Pasteur vaccine strain, the vrrA PCR-RFLP profiles of the B. anthracis were separated into three groups, which were different from those of the B. cereus strains. Ribotyping separated the B. anthracis isolates into seven ribotypes, and a common fragment of an approximately 850 bp band from the ERIC-PCR fingerprints separated most B. anthracis strains into two groups. VrrA/cerAB PCR-RFLP, ribotyping and ERIC-PCR generated 18, 22 and 23 types, respectively, from B. cereus strains. The results suggest that a combination of all three methods provides a high resolution typing method for B. anthracis and B. cereus. Compared with ribotyping and ERIC-PCR, PCR-RFLP is simple to perform and has potential as a rapid method for typing and discriminating B. anthracis strains from other B. cereus group bacteria.

Bacillus anthracis↗
PubMed2000

Erythromycin inhibits beta2-integrins (CD11b/CD18) expression, interleukin-8 release and intracellular oxidative metabolism in neutrophils.

Macrolides have therapeutic benefits on chronic inflammatory airway diseases. Thus, macrolides are supposed to have variable biological effects apart from antimicrobial activity. Neutrophil adherence and influx with oxidants and cytokines production implicates involvement in airway inflammation. To investigate whether erythromycin (EM) affects neutrophil activity in vitro, lipopolysaccharide (LPS)-treated neutrophils were continuously incubated for 4 h in the absence or presence of increasing doses of EM from 1 microg ml(-1) to 100 microg ml(-1) in the last 2 h. Leukocyte adhesion molecules Mac-1 and intracellular H2O2(DCFH) were determined by flowcytometric assay. IL-8 and TNFalpha in supernatant was measured by ELISA method. The expression of Mac-1 and mean intracellular DCF fluorescence intensity (DCFH) of neutrophils significantly increased after stimulation with LPS. Pretreatment with EM significantly decreased LPS induced Mac-1 expression on neutrophils compared with LPS stimulation only. EM alone (100 microg ml(-1)) also decreased Mac-1 expression on neutrophils. EM significantly reduced the LPS-increased DCFH. EM alone (100 microg ml(-1)) also caused a decrease in DCFH. Increasing doses of EM also significantly decreased the IL-8 released by LPS-stimulated neutrophils. In conclusion, EM exerts a direct effect on the neutrophils by downregulating the expression of beta2-integrin on neutrophils, thus leading to a decrease in the intracellular H2O2, as well as the production of IL-8. Our conclusion provides an explanation for the clinical efficacy of erythromycin in neutrophil-mediated airway inflammation.

Anti-Bacterial Agents↗
PubMed2000

Chronic inhibition of nitric oxide ameliorates splanchnic hyposensitivity to glypressin in a hemorrhage-transfused rat model of portal hypertension.

BACKGROUND: Vasopressin given during hemorrhage is less effective than when given during a stable state in experimental portal hypertension or patients with cirrhosis (the so-called hyposensitivity phenomenon). This study investigated whether chronic inhibition of nitric oxide (NO) synthesis by NG-nitro-L-arginine methyl ester (L-NAME), a non-selective NO synthase inhibitor, could potentiate the portal-hypotensive effect of glypressin (a long-acting vasopressin analogue) in portal-hypertensive rats during acute bleeding status. METHODS: Portal hypertension was induced by partial portal vein ligation (PVL). Rats were divided to receive either L-NAME (approximately 25 mg/kg/day in tap water) or placebo (tap water) treatment orally from 2 days prior to until 14 days after the operation. At the end of treatment, L-NAME-and placebo-treated PVL rats were subdivided into without-bleeding and with-bleeding groups to assess the effects of glypressin (0.07 mg/kg) on systemic and portal hemodynamics. In rats with a hypotensive hemorrhage, 4.5 ml of blood was withdrawn and 50% of the withdrawn blood was reinfused before the administration of glypressin. RESULTS: As compared with placebo-treated rats, chronic treatment with L-NAME in PVL rats significantly increased mean arterial pressure (P < 0.001) without modulating portal pressure (P > 0.05). In placebo-treated PVL rats, glypressin resulted in a less decrease in portal pressure in rats with bleeding than in those without bleeding (P < 0.05). For PVL rats with bleeding, the portal-hypotensive effect of glypressin was significantly potentiated after chronic L-NAME treatment (P < 0.05). CONCLUSIONS: Chronic inhibition of NO alleviates the splanchnic hyposensitivity to glypressin observed in bleeding PVL rats, suggesting the pathophysiological role of nitric oxide in mediating this splanchnic hyposensitivity.

Animals↗
PubMed2000

Effects of prostacyclin inhibition on splanchnic hyposensitivity to glypressin in a hemorrhage-transfused rat model of portal hypertension.

BACKGROUND: Hyposensitivity to vasopressin is a well-documented phenomenon in animals with portal hypertension and patients with cirrhosis and hemorrhage. Similar findings exist with infusion of glypressin (a long-acting vasopressin analogue), and this phenomenon could be ameliorated by inhibition of nitric oxide (NO) synthase. Besides NO, excessive formation of prostacyclin (PGI2) has been shown to play an important role in the development of hyperdynamic circulation and the mediation of hyporeactivity to vasoconstrictors in portal-hypertensive states. This study was designed to investigate whether the blockade of PGI2 activity by indomethacin infusion could enhance the portal-hypotensive effect of glypressin in portal-hypertensive rats with bleeding. METHODS: Portal hypertension was induced by partial portal vein ligation (PVL). Fourteen days after operation systemic and portal hemodynamics were measured in stable or bleeding PVL rats receiving intravenous glypressin (0.07 mg/kg) or indomethacin (5 mg/kg) followed by glypressin infusion. In rats with a hypotensive hemorrhage 4.5 ml of blood was withdrawn, and 50% of the withdrawn blood was reinfused before the administration of glypressin or indomethacin. RESULTS: Splanchnic hyposensitivity to glypressin was shown in hemorrhage-transfused PVL rats. Indomethacin infusion did not cause significant systemic and portal-hemodynamic changes in bleeding PVL rats (P > 0.05). The addition of indomethacin significantly enhanced the portal-hypotensive effects of glypressin and potentiated the increases in mean arterial pressure induced by glypressin infusion in bleeding PVL rats. CONCLUSIONS: The improvement of splanchnic hyposensitivity to glypressin in a hemorrhage-transfused rat model of portal hypertension by the administration of indomethacin suggests that PGI2 has in the development of this hyposensitivity.

Analysis of Variance↗
PubMed2000

Outbreak investigation of nosocomial enterobacter cloacae bacteraemia in a neonatal intensive care unit.

Over a period of 7 months, 23 patients hospitalized in a neonatal intensive care unit (NICU) developed nosocomial Enterobacter cloacae bacteraemia. Contaminated saline for preparing heparin solution was initially identified as the common source of E. cloacae bacteraemia. Although environmental sanitation was enforced, the outbreak continued. E. cloacae has always been isolated from various cultures of the environmental specimens, from the hands of personnel and from the faeces of patients. All of the 23 bacteraemic isolates and 8 stool isolates from infected infants, as well as the 17 isolates from environmental specimens were found to be of the same genotype using the polymerase chain reaction-based DNA fingerprinting method. After various infection control methods were instituted, the outbreak eventually came under control. For epidemiological investigation, 23 neonates without E. cloacae bacteraemia were matched for case-control study. Nineteen (83%) of the case-patients were premature. The significant risk factors leading to E. cloacae bacteraemia in the NICU included small gestation age, low birthweight, exposure to personnel with contaminated hands and the presence of E. cloacae in the stool carriage (p=0.003, 0.007, 0.018 and 0.040, respectively). The gastrointestinal tracts of the patients and environmental surfaces appeared to be the principal sites of bacterial reservoir. In conclusion, the outbreak of E. cloacae bacteraemia was caused by a particular strain and possibly via multiple modes of transmission, including a bottle of contaminated saline as an initial common source, endogenous spread from the gastrointestinal tract and successive cross-infections between patients, hands of personnel and the environment. Effective infection control requires a multidisciplinary approach and reinforcement of infection control procedures, including aseptic technique, hand washing, proper isolation and disinfection of environmental surfaces.

Bacteremia↗
PubMed2000

Thymus size and its relationship to perinatal events.

A retrospective study was conducted to assess radiographically the thymus size in well and sick neonates and to search for a possible relationship to perinatal events. Thymus size was expressed as cardiothymic:thoracic ratio (CT/T) by measuring the width of the cardiothymic shadow at the level of carina and dividing it by the width of the thorax at the costophrenic angles. The CT/T was measured on chest radiographs obtained on day 1 in well term neonates consecutively born in our nursery and sick neonates with meconium staining of the amniotic fluid, meconium aspiration syndrome or respiratory distress syndrome (RDS). Neonates with congenital anomalies, congenital heart disease or intrauterine growth retardation were excluded. There were no significant relationships between CT/T and sex, birth route, birthweight or gestational age in well and sick term neonates. The CT/T were comparable among well and sick term neonates and were significantly greater in the preterm neonates with RDS than in the preterm neonates without RDS. The CT/T was correlated to the birth route only in the preterm neonates. We conclude that thymus involution in the perinatal period is a complex process and the response is different between term and preterm neonates.

Birth Weight↗
PubMed2000

An endoscopic injection with N-butyl-2-cyanoacrylate used for colonic variceal bleeding: a case report and review of the literature.

We report a 64-yr-old patient with liver cirrhosis and bleeding esophageal varices that were obliterated by repeated endoscopic sclerotherapy. Eleven years later, he developed a massive, life-threatening rectosigmoid variceal hemorrhage. An endoscopic injection with N-butyl-2-cyanoacrylate (Histoacryl), performed over the rectosigmoid varices, achieved temporary hemostasis. The etiology, prevalence, relationship with portal hypertension, diagnosis, and treatment of colorectal varices are discussed.

Colon, Sigmoid↗
PubMed2000

Treatment of mastalgia with tamoxifen in male patients with liver cirrhosis: a randomized crossover study.

OBJECTIVE: Mastalgia is occasionally found in patients with liver cirrhosis, especially in those receiving spironolactone for treatment of ascites. The pathogenesis is still unclear. Estrogen excess in cirrhotic patients and estrogenic effects of the spironolactone are possible leading causes. Treatment directed against the preponderance of estrogenic stimulation in these patients has never been investigated. This study was designed to investigate the efficacy and safety of tamoxifen, an estrogen antagonist, on mastalgia in patients with liver cirrhosis. METHODS: A total of 16 male cirrhotic patients with mastalgia were randomly assigned to two groups. One group was treated with tamoxifen (20 mg p.o., b.i.d.) for 1 month, followed by placebo for the next month. The other group was treated in the reverse order. All patients received spironolactone for ascites and/or peripheral edema, and the drug was continued during the study period. The size of the breasts and the degree of breast pain and tenderness were recorded in all subjects before and after the treatment periods. Serum levels of estradiol and testosterone were measured using the radioimmunoassay method. RESULTS: Of the 16 patients, 14 experienced a decrease or disappearance of the breast pain and/or tenderness during the tamoxifen treatment period, whereas only two of the 16 patients felt an improvement during the placebo period (p < 0.05). There were significant improvements in the breast pain and tenderness scores and decreases in the breast sizes during the tamoxifen treatment period (before vs after: 1.4+/-0.3 vs 0.4+/-0.2, p = 0.002; 1.9+/-0.2 vs 0.5+/-0.2, p < 0.001; and 6.8+/-0.6 vs 5.5+/-0.6 cm, p = 0.02, respectively), whereas no obvious change was seen during the placebo period. Serum levels of estradiol and testosterone did not change significantly after the tamoxifen or placebo treatments (p > 0.05). No major side effects were noted during the therapeutic periods. CONCLUSIONS: Tamoxifen is effective and safe in the management of mastalgia in male cirrhotic patients taking spironolactone.

Aged↗
PubMed2000

Identification of a prodromal period in Crohn's disease but not ulcerative colitis.

OBJECTIVES: Irritable bowel syndrome, a common gastrointestinal diagnosis, has not been clearly studied in inflammatory bowel disease. Some of the residual symptoms in subjects treated with Crohn's disease and ulcerative colitis are thought to be related to irritable bowel syndrome. The aims of this study were 1) to describe the duration and nature of complaints before the diagnosis of Crohn's disease and ulcerative colitis (prodromal period), and 2) to determine the role of IBS in this prodromal period. METHODS: A total of 66 patients with confirmed inflammatory bowel disease were enrolled in the study. The subjects received a questionnaire to ascertain the nature and duration of symptoms preceding the diagnosis of Crohn's disease or ulcerative colitis, including features described under the Rome criteria for irritable bowel syndrome. RESULTS: Of the 66 subjects analyzed, 45 had Crohn's disease and 21 had ulcerative colitis. The prodromal period was 7.7 +/- 10.7 yr for Crohn's disease and 1.2 +/- 1.8 yr for ulcerative colitis (p < 0.05). Once patients meeting the Rome criteria for irritable bowel syndrome during the prodrome were excluded, the duration of the prodromal period (non-IBS) for ulcerative colitis dropped to 0.8 +/- 1.3 yr compared to 6.9 +/- 9.8 yr in the Crohn's disease group (p < 0.05). The symptoms of the non-IBS prodrome in subjects with Crohn's disease were bloating, diarrhea, stomach pain, heartburn, fever, weight loss, and fatigue. Further analysis demonstrated that subjects whose Crohn's disease initially began as colonic disease had a longer prodrome than with small bowel. In the non-IBS Crohn's group, there was also a correlation between the age at the time of diagnosis and the duration of prodrome (r = 0.67, p < 0.0001). CONCLUSIONS: There is a significant prodromal period before the time of diagnosis of Crohn's disease that is not found in ulcerative colitis even after exclusion of subjects with IBS.

Adult↗
PubMed2000

Eradication of small intestinal bacterial overgrowth reduces symptoms of irritable bowel syndrome.

OBJECTIVES: Irritable bowel syndrome is the most common gastrointestinal diagnosis. The symptoms of irritable bowel syndrome are similar to those of small intestinal bacterial overgrowth. The purpose of this study was to test whether overgrowth is associated with irritable bowel syndrome and whether treatment of overgrowth reduces their intestinal complaints. METHODS: Two hundred two subjects in a prospective database of subjects referred from the community undergoing a lactulose hydrogen breath test for assessment of overgrowth were Rome I criteria positive for irritable bowel syndrome. They were treated with open label antibiotics after positive breath test. Subjects returning for follow-up breath test to confirm eradication of overgrowth were also assessed. Subjects with inflammatory bowel disease, abdominal surgery, or subjects demonstrating rapid transit were excluded. Baseline and after treatment symptoms were rated on visual analog scales for bloating, diarrhea, abdominal pain, defecation relief, mucous, sensation of incomplete evacuation, straining, and urgency. Subjects were blinded to their breath test results until completion of the questionnaire. RESULTS: Of 202 irritable bowel syndrome patients, 157 (78%) had overgrowth. Of these, 47 had follow-up testing. Twenty-five of 47 follow-up subjects had eradication of small intestinal bacterial overgrowth. Comparison of those that eradicated to those that failed to eradicate revealed an improvement in irritable bowel syndrome symptoms with diarrhea and abdominal pain being statistically significant after Bonferroni correction (p < 0.05). Furthermore, 48% of eradicated subjects no longer met Rome criteria (chi2 = 12.0, p < 0.001). No difference was seen if eradication was not successful. CONCLUSIONS: Small intestinal bacterial overgrowth is associated with irritable bowel syndrome. Eradication of the overgrowth eliminates irritable bowel syndrome by study criteria in 48% of subjects.

Adult↗
PubMed2000

Slowing of intestinal transit by fat depends on naloxone-blockable efferent, opioid pathway.

Slowing of transit through the proximal small intestine by fat in the distal gut is termed the ileal brake. Intravenous naloxone, an opioid receptor antagonist, abolished the fat-induced ileal brake, suggesting that an endogenous opioid pathway may be involved in this response. To test the hypothesis that slowing of intestinal transit by fat in the distal half of the gut depends on an opioid pathway located on the efferent limb of this response, we compared intestinal transit in dogs equipped with duodenal and midgut fistulas while naloxone was either compartmentalized with oleate to the distal half of the gut or with buffer to the proximal half of the gut. We found that intestinal transit depended on the perfusion conditions (P<0.00001). Specifically, compared with ileal brake (marker recovery of 35.7+/-7.4%), intestinal transit was accelerated when naloxone was delivered into the proximal half of the gut (76.2+/-5.2%) (P<0.005) but not the distal half of the gut (29.4+/-5.4%). We conclude that slowing of intestinal transit by fat in the distal half of the gut depends on an opioid pathway located on the efferent limb of the ileal brake.

Animals↗
PubMed2000

Nitric oxide modulates interleukin-1beta and tumor necrosis factor-alpha synthesis by alveolar macrophages in pulmonary tuberculosis.

Interleukin (IL)-1beta and tumor necrosis factor (TNF)-alpha released from alveolar macrophages (AM) in pulmonary tuberculosis (TB) are important in host defense against mycobacterial infection. Nitric oxide (NO) production is enhanced in AM of TB patients. We examined whether NO was implicated in (IL)-1beta and TNF-alpha synthesis by AM of TB patients. Purified AM were retrieved by bronchoalveolar lavage from 11 TB patients and 10 normal subjects, and were cultured with or without the NO inhibitor N(G)-monomethyl-L-arginine (L-NMMA). The release of IL-1beta and TNF-alpha, and expression of their messenger RNAs (mRNAs), were determined by enzyme-linked immunosorbent assay and Northern blot analysis. The release of IL-1beta and TNF-alpha was greater from AM of TB patients than from AM of normal subjects. L-NMMA inhibited nitrite, IL-1beta, and TNF-alpha production in TB patients. The mRNA expression for IL-1beta and TNF-alpha was upregulated in TB patients and was depressed by L-NMMA. Immunocytochemistry done with a monoclonal antibody against the p65 subunit of nuclear factor (NF)-kappaB showed that NF-kappaB was highly expressed and translocated to the nuclei of AM from TB patients, and was inhibited by L-NMMA. Inhibition of NF-kappaB by pyrrolidine dithiocarbamate attenuated IL-1beta and TNF-alpha synthesis. In conclusion, enhanced NO generation by AM of TB patients plays an autoregulatory role in amplifying the synthesis of proinflammatory cytokines, probably through NF-kappaB activation.

Adult↗