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Biomedical subjects

C L Lu

Publications and source records attributed to C L Lu.

At least 55 records · Page 3Linked to original sources
PubMed1999

Multiple functions of polypeptides mediated by distinct domains interacting with different receptors.

There exist multiple functions of polypeptide molecules. Both a polypeptide molecule interacting with one receptor, and distinct domains of the molecule interacting with different receptors could induce different intracellular signal transduction to elicit multiple functions. This review highlights the distinct domains of the polypeptide molecule interacting with different receptors to elicit multiple functions. It includes distinct domains, different receptor mechanisms, and different signal transduction of the polypeptide molecule.

Animals↗
PubMed1999

Endothelin-1 is a candidate mediating intestinal dysmotility in patients with acute pancreatitis.

We studied whether gastrointestinal transit was disturbed during acute pancreatitis and attempted to identify which mechanisms might be involved in acute pancreatitis. Using a noninvasive hydrogen breath test to determine the orocecal transit time, 24 patients with the clinical diagnosis of acute pancreatitis were enrolled into the intestinal motility study. Orocecal transit time was measured twice in all patients: once at the acute stage and once at recovery. Blood was obtained to study amylase, lipase, C-reactive protein, erythrocyte sedimentation rate, and endothelin-1 and nitrate/nitrite levels. Orocecal transit times measured at the acute stage were significantly delayed compared with those at recovery (mean values +/- SEM, 130.0 +/- 9.0 vs 80.8 +/- 7.4 min, P < 0.001). Plasma endothelin-1 levels exhibited a positive correlation with orocecal transit times in the acute stage (r = 0.509, P = 0.011). The percentages of altered orocecal transit times also correlated with the percentages of altered plasma endothelin-1 levels (r = 0.751, P < 0.001). Plasma nitrate/nitrite levels significantly decreased at the acute stage compared with those at recovery (5.25 +/- 0.82 vs 10.20 +/- 1.24 microM, P < 0.05). We conclude that intestinal transit is delayed in patients with mild to moderate acute pancreatitis. Elevated plasma endothelin-1 levels in the acute stage may be one mechanism mediating intestinal dysmotility.

Acute Disease↗
PubMed1999

Postprandial changes of sympathovagal balance measured by heart rate variability.

The aim of this study was to investigate the sympathovagal balance after meals by measuring the spectral analysis of heart rate variability (HRV). Nine healthy volunteers were enrolled in this study. The electrocardiogram (ECG) was recorded for 30 min in a fasting state and 60 min after a 500-kcal test meal. The HRV was derived from the ECG and was measured by power spectral analysis using fast-Fourier transform algorithm. It reveals two dominant spectral components. The low-frequency (LF) band reflects primarily sympathetic activity with some parasympathetic input. The high-frequency (HF) band is a reflection of parasympathetic (vagal) activity. The LF-to-HF ratio is considered a marker of sympathovagal balance. It was found that the postprandial LF-to-HF ratio, compared with the fasting state, was significantly increased at both the first 30 min (2.50 +/- 0.49 vs 1.78 +/- 0.33, P < 0.05) and the second 30 min (2.68 +/- 0.55 vs 1.78 +/- 0.33, P < 0.05). The postprandial HF diminished significantly at both the first (16.0 +/- 0.5 vs 21.8 +/- 4.2, P < 0.05) and the second (13.8 +/- 9.5 vs 21.8 +/- 4.2, P < 0.05) 30-min period. In conclusion, the postprandial sympathovagal ratio shows a sustained elevation lasting 1 hr, mainly attributed to diminished vagal activity.

Adult↗
PubMed1999

Supportive treatment, resection and transcatheter arterial chemoembolization in resectable hepatocellular carcinoma: an analysis of survival in 419 patients.

OBJECTIVE AND DESIGN: Both surgical resection and transcatheter arterial chemoembolization (TACE) are effective treatments for hepatocellular carcinoma (HCC). Few reports have compared the different treatment modalities for resectable HCC based on clinically matched groups. The aim of this study was to compare the survival rate after surgery, TACE or supportive treatment in resectable HCC patients, and also in elderly patients (> or = 70 y/o). METHODS: From 1984 to 1993, 419 consecutive patients with resectable HCC were included in this study. Of these, 311 (74%) underwent resection of tumours and 46 (11%) refused operation, opting instead for TACE. The remaining 62 (15%) who refused both methods of treatment were given supportive care. Univariate and multivariate analyses for prognostic factors and the 5-year survival rate among the groups were studied. RESULTS: Both surgical resection and TACE groups had a better 5-year survival rate than the supportive treatment group (43% and 34% vs. 7%). There was no difference in survival between the surgery and TACE groups. However, the 5-year survival rate was 11% in TACE and 41% in the surgical group when the patients were > or = 70. In multivariate analysis, female sex (P = 0.0466), tumour size < or = 3 cm (P = 0.0001), alpha-fetoprotein (AFP) < 400 U/l (P = 0.0036), single tumour (P = 0.0474), serum creatinine < or = 1.5 mg/dl (P = 0.0006) and alkaline phosphatase (AP) < or = 100 U/l (P = 0.0007) are associated with good prognosis for resectable HCC. CONCLUSION: TACE is an alternative for resectable HCC. Tumour size, tumour number, AFP level, renal function, AP level and female sex are prognostic factors. In elderly people, TACE must be used prudently and has a worse prognosis.

Age Factors↗
PubMed1999

Clinical significance of portal lymphoid aggregates/follicles in Chinese patients with chronic hepatitis C.

OBJECTIVE: Portal lymphoid aggregates/follicles (lymphoid A/F) is a characteristically histological finding in patients with chronic hepatitis C. We assessed the prevalence of lymphoid A/F in Chinese patients with chronic hepatitis C and evaluated the correlation of this phenomenon with clinical, biochemical, immunological, virological, and other histological features of these patients. METHODS: Eighty-nine Chinese patients with chronic hepatitis C were enrolled and portal lymphoid A/F was evaluated in liver biopsy. Clinical, biochemical, immunological, histological, and virological data, including serum HCV RNA titer and HCV genotype and the response to interferon therapy, were compared between patients with and without portal lymphoid A/F. RESULTS: Twenty-nine (33%) of 89 patients with chronic hepatitis C had portal lymphoid A/F. Patients with lymphoid A/F had a significantly higher frequency of HCV genotype 1b infection (p = 0.039) and had a significantly higher mean score of bile duct damage, periportal necroinflammation, and portal inflammation in liver histologies when compared with patients without lymphoid A/F. No significant difference in sex distribution, mean age, history of blood transfusion, serum liver biochemistry, presence of serum autoantibodies/cryoglobulinemia, serum viral titer, and response to interferon therapy was noted between the two groups. Multivariate logistic regression analysis showed HCV genotype 1b infection and periportal necroinflammation were significant independent predictors associated with portal lymphoid A/F. CONCLUSIONS: The presence of portal lymphoid A/F in Chinese patients with chronic hepatitis C was significantly correlated with HCV genotype 1b infection and periportal necroinflammation.

Biopsy↗
PubMed1999

Relationship of the subgingival microbiota to a chairside test for aspartate aminotransferase in gingival crevicular fluid.

BACKGROUND: The aim of the present study was to evaluate the association between the occurrence of certain specific periodontal pathogens and aspartate aminotransferase (AST) levels in gingival crevicular fluid (GCF). METHODS: Thirty systemically healthy subjects with moderate to advanced periodontitis were selected. Within each subject, the AST contents of GCF from sites with probing depth between 5 mm and 7 mm were measured using a chairside colorimetric test. AST-positive site refers to one that had an AST level > or = 800 microIU. Subgingival plaque samples from one AST-positive and one negative site were collected for microbiological examination. One site with probing depth < or = 3 mm and no gingival inflammation was selected as a healthy control. Clinical parameters of the chosen sites, including the plaque index and gingival index scores, probing depth, and clinical attachment level were measured. Culture and immunofluorescence (IF) were used for detecting common periodontal pathogens, including Actinobacillus actinomycetemcomitans, Peptostreptococcus micros, Campylobacter rectus, Eikenella corrodens, Fusobacterium nucleatum, Capnocytophaga species, Prevotella intermedia, Prevotella melaninogenica, and Porphyromonas gingivalis. Logistic regression was used to analyze the correlation between the AST test and certain specific pathogens. RESULTS: The GCF scores and total cultivable bacterial counts were higher in AST-positive sites than either AST-negative or healthy sites. The prevalence and proportions of specific periodontal pathogens such as C rectus, E. corrodens, F. nucleatum, Capnocytophaga species, P. intermedia, and P. gingivalis were significantly higher in positive than in negative sites. In analyzing the correlation of the proportion of 6 pathogens with the AST test by logistic regression, only P. gingivalis showed a significant positive correlation. The odds ratio of having a high proportion of P. gingivalis in the presence of a positive AST test was 1.21. CONCLUSIONS: The present study showed that at AST-positive sites, there is a higher prevalence and higher proportion of certain periodontal pathogens. Although only the correlation of P. gingivalis and AST values was statistically significant, the results imply that certain periodontal pathogens may be associated with elevation of AST levels in GCF.

Adult↗
PubMed1999

Microbiological response of localized sites with recurrent periodontitis in maintenance patients treated with tetracycline fibers.

BACKGROUND: Whether adjunctive tetracycline fibers can provide an additive effect to scaling and root planing in treating non-responsive sites in maintenance subjects is still controversial. Recolonization of the bacteria from untreated sites or from the extracrevicular region may explain the insignificant response to local therapy. The purpose of the present study was to evaluate the microbiological response of sites treated with tetracycline fibers combined with scaling and root planing. METHODS: The study was conducted in a split-mouth design. Thirty patients on maintenance therapy having at least 2 non-adjacent sites in separate quadrants with probing depths between 4 to 8 mm with bleeding on probing, or aspartate aminotransferase enzyme levels > 800 microIU in the gingival crevicular fluid, were treated with scaling and root planing plus tetracycline fibers or with scaling and root planing only. Subgingival plaque samples were collected at baseline, and 1, 3, and 6 months following treatment. A. actino-mycetemcomitans, C. rectus, B. forsythus, E. corrodens, F. nucleatum, P. gingivalis, and P. intermedia were detected by culture, immunofluorescence, or PCR technique. RESULTS: There was a reduction of total bacterial cell count, as well as of certain periodontal pathogens, following treatment. The prevalence of A. actinomycetemcomitans, B. forsythus, and P. gingivalis and the mean proportions of C. rectus, P. intermedia, F. nucleatum, and P. gingivalis decreased after therapy, but there was no statistically significant difference between the 2 treatment groups with respect to bacterial proportions or the number of positive sites. Besides, the pathogens could not be eliminated from the periodontal pocket, and recolonization of the pocket was noted at 3 months post-treatment. CONCLUSIONS: Bacteria located within the cheek, tongue mucosa, saliva, or untreated sites may contribute to reinfection of the pockets and explain the insignificant response to local tetracycline therapy.

Adult↗
PubMed1999

[Ciliary neurotrophic factor prevents NO mediated cytotoxicity in cultured hippocampal neurons].

The effects of ciliary neurotrophic factor on nitric oxide (NO)-induced cytotoxicity were examined in primary cultures of rat hippocampal neurons. The neurotoxicity was induced by NO donors, such as sodium nitroprusside (SNP), s-nitroso-N-acetylpenicillamine (SNAP), NOS substrate, L-arginine (L-Arg) and ionomycin (a calcium ionophore). Preincubation of the cultures with ciliary neurotrophic factor (CNTF) for 24 h promoted neuronal survival and decreased the LDH efflux and the level of NO induced by ionomycin. The protective effects of CNTF against NO cytotoxicity were concentration-dependent. The above findings suggest that CNTF promotes the survival of neurons in the hippocampus by preventing NO mediated neurotoxicity.

Animals↗
PubMed1999

[Protection of spinal motorneurons of section sciatic nerve by transplantation of NT-4 genetically expression cells into the side of section].

The NT-4 genetically engineered cells were made by infecting L-6TG cell (a rat myoblast cell line) in vitro with a retroviral vector pN2A containing the rat NT-4 cDNA. The bioactivities were determined by bioassay of PC12 cell survival rate. The rat with left sciatic nerve transaction was used as a model for treatment by implanting NT-4 genetically modified cell. The condition of motorneurons was assessed by Nissl stain and ChE stain. The results showed that: (1) the percentage of surviving Nissl-stained neurons on the lessened side of NT-4 (+) grafts significantly increased as compared to that with NT-4 (-) grafts 2-3 weeks and 3 months after sciatic nerve transaction, and (2) the grafted cells produced significant increase in the positive ChE stained area after sciatic nerve transaction in 1-3 weeks. Our observations indicate that adult motor neurons are still able to respond to neurotrophic factors and they may require the factors for survival.

Animals↗
PubMed1998

The relationship of Helicobacter pylori colonization, the serum pepsinogen A level, and gastric resection.

The serum levels of pepsinogen A (PGA) were measured in patients who underwent various forms of gastric resection to assess whether Helicobacter pylori (HP) colonization has any influence. Included in this study were 48 patients who underwent subtotal gastrectomy for a peptic ulcer (SGPU), 36 who underwent radical subtotal gastrectomy for gastric carcinoma (SGGC), 16 who underwent truncal vagotomy plus antrectomy (TV + AE), 24 with recurrent ulcer (RU) and 27 who underwent total gastrectomy (TG). The mean serum PGA levels in these five groups and in 40 healthy controls were 49.1 +/- 30.4 ng/ml, 30.0 +/- 14.8 ng/ml, 44.8 +/- 21.7 ng/ml, 66.4 +/- 42.8 ng/ml, 8.7 +/- 3.0 ng/ml, and 94.7 +/- 27.9 ng/ml, respectively. All patients except those with RU showed a diminished PGA level. The HP colonization rates of the patients who underwent partial resection were 45.8%, 22.2%, 50%, and 54.2%, respectively (P < 0.05). Age, gender, smoking, the type of gastroenterostomy, and underlying disease did not exert any influence on the measured PGA levels. However, higher PGA levels were observed in HP-colonized patients who either underwent SGPU or had RU. We conclude that various forms of distal gastrectomy, but not RU, elicit an indistinguishable acid secretory ability while HP colonization is responsible for the higher serum PGA levels in some patients following peptic ulcer surgery.

Aged↗
PubMed1998

The molecular basis for bidirectional communication between the immune and neuroendocrine systems.

IL-2 has analgesic effects in both central and peripheral nervous systems. There are two distinct domains in IL-2 molecule mediating immunologic and analgesic activity, respectively. The analgesic domain of IL-2 may be composed of the 44th Phe, 45th Tyr, 107th Tyr, and 117th Phe residues that are located closely in the tertiary structure of IL-2. The analgesic activity may be mediated through the analgesic domain interaction with opioid receptor. In addition to peptides, cytokines may directly bind to peptide receptors, other than their specific cytokine receptors themselves. Conversely, peptides may also interact with cytokine receptors. Thus, peptide neurotransmitters and hormones may serve as endogenous regulators of the immune system, and cytokines may also serve as neurotransmitters. Multiple actions might be mediated by interactions between distinct domains of bioactive molecules with different receptors.

Analgesics↗
PubMed1998

Abnormal vagal cholinergic function and psychological behaviors in irritable bowel syndrome patients: a hospital-based Oriental study.

Irritable bowel syndrome (IBS) patients in Western countries usually manifest autonomic nerve dysfunctions and abnormal psychological behaviors. The purpose of this study was to assess whether Oriental IBS patients with predominant bowel symptoms also exhibited similar abnormalities. We enrolled 40 IBS patients from the outpatient clinic and 20 controls with normal daily bowel habit for study. The IBS patients were further divided according to their predominant bowel habit: 20 were constipation-predominant and 20 were diarrhea-predominant. Sympathetic function was evaluated by sympathetic skin response (SSR) while vagal cholinergic function was determined by measuring R-R interval variation (RRIV) in electrocardiography during rest and deep breathing. Psychological parameters were assessed by scales of the Minnesota Multiphasic Personality Inventory (MMPI) and the Hopkins Symptom Checklist (HSCL-90). IBS patients, despite their bowel habit, showed normal SSR response. RRIV during deep breathing was significantly lower in constipation-predominant IBS patients than in controls or diarrhea-predominant IBS patients (16.5+/-3.1% vs 20.5+/-4.8% and 21.5+/-4.6%, P < 0.001). IBS patients also exhibited abnormal MMPI measuring scores on depression, hysteria, paranoia, and masculinity/femininity scales. In addition, they also had more severe psychological distress in the items of HSCL-90 measurement. In conclusion, vagal dysfunction characterizes Oriental constipation-predominant IBS patients seeking medical help. Abnormal psychoneurotic profiles also exist in these IBS patients, irrespective of their bowel habits.

Attitude to Health↗
PubMed1998

Age is one of the risk factors in developing gallstone disease in Taiwan.

OBJECTIVES: To assess the prevalence and risk factors of gallstone disease (GSD) in Taiwan. DESIGN: Descriptive and cross-sectional. METHODS: A prospective ultrasonographic study of GSD was conducted in 3647 Chinese subjects who received a paid hospital physical check-up. Their demographic characteristics and biochemical parameters were recorded and compared. Ultrasonographic diagnosis revealed 2946 (M/F: 1838/1108) with normal gallbladder, 286 (M/F: 196/90) with gallbladder stones, 100 (M/F: 56/44) with previous cholecystectomy for gallstones, 243 (M/F: 174/69) with gallbladder polyps, 17 (M/F: 10/7) with mixed gallbladder stones/polyps and 35 as 'miscellaneous'. We enrolled subjects showing either gallbladder stones or cholecystectomy for gallstones in the GSD group. RESULTS: Excluding those subjects with mixed gallbladder stones/polyps, the overall prevalence of GSD in the studied group was 10.7%. The studied factors manifesting an increase in risk for the development of GSD were age (P<0.05), high body mass index (P< 0.05), diabetes mellitus (adjusted odds ratio: 1.998; P< 0.05) and glucose intolerance (adjusted odds ratio: 2.056; P<0.05) by multivariate analysis. Other demographic characteristics and biochemical parameters, such as body height, ABO blood type, cigarette smoking, alcohol consumption, blood pressure, lipid profiles, hepatitis B virus infection, liver function and multiparity did not show any correlation to GSD. CONCLUSIONS: Age, high body mass index, diabetes mellitus and glucose intolerance are the risk factors for developing GSD in Taiwan.

Adult↗
PubMed1998

An improved electrogastrographic system in measuring myoelectrical parameters.

This study assessed the reliability of an improved electrogastrographic (EGG) system in recording stomach myoelectrical parameters and tried to establish the normal ranges of myoelectricity using this system. The analytical software of the current system mainly included an autoregressive modelling program to compute myoelectrical frequency and power. Forty healthy subjects were enrolled to receive myoelectrical measurement in two consecutively fasting and one postprandial 30 min sessions. The myoelectrical frequencies in both fasting and postprandial sessions were almost three cycles per min (c.p.m.) and showed little variation. The percentage of dominant frequencies (2.5-3.5 c.p.m.) in three sessions was approximately 80% while the computed myoelectrical powers in the first and second fasting sessions exhibited a significant correlation (r=0.84, P<0.001). Meal ingestion increased the myoelectrical powers by 6.8dB compared with the second fasting recording (P< 0.001). The mean variation in myoelectrical amplitude for the ratio of second: first fasting session was 110.3+/-88.8% (16-478%, median 88%). This new EGG system is, indeed, reliable for measuring myoelectrical frequency and power, whereas the interassay of recorded amplitudes appears markedly variable.

Adult↗
PubMed1998

Helicobacter pylori colonization does not influence the symptomatic response to prokinetic agents in patients with functional dyspepsia.

Functional dyspepsia (FD) is very common, but the pathogenesis of Helicobacter pylori leading to FD is still debated. The aim of this study was first to evaluate the impact of H. pylori colonization on the efficacy of Paspertase (a metoclopramide plus exogenous enzymes regimen for FD patients) and, second, to compare the prevalence of H. pylori infection in FD patients with the general population. Seventy-four consecutive FD patients were enrolled undergoing Paspertase treatment. The symptomatic response was evaluated according to 1-4 scales of six main dyspeptic symptoms (i.e. epigastric pain/discomfort, early satiety, heartburn, nausea/vomiting, abdominal fullness/bloating, and belching). Nine hundred and seventy healthy subjects undergoing a paid physical check-up were included to study the status of H. pylori colonization. The demographic data and basal symptom scores between 43 H. pylori-positive and 31 H. pylori-negative patients were not significantly different. Total and individual symptom scores improved significantly after 4 weeks of Paspertase therapy (P < 0.05), irrespective of H. pylori infection. The prevalences of H. pylori were very similar in FD patients and the general population (58.1 vs 58.0%, NS). In conclusion, these observations suggest that H. pylori colonization is not significant in FD patients of Taiwan while a short-term prokinetic medication is effective for these patients, irrespective of H. pylori status.

Adult↗
PubMed1998

Relationships between serum aminotransferase levels, liver histologies and virological status in patients with chronic hepatitis C in Taiwan.

In patients with chronic hepatitis C, the relationships between serum alanine aminotransferase (ALT) levels, histological liver injury and serum hepatitis C virus (HCV) RNA titres remain controversial. To evaluate these relationships, 93 Chinese patients with histological diagnosis of chronic hepatitis C were enrolled for this study. Serum ALT levels, HCV-RNA titres and HCV genotypes were examined. The histology was evaluated according to a modified histological activity score based on the degree of periportal necro-inflammation, intralobular necro-inflammation, portal inflammation, total necro-inflammation and fibrosis. The mean serum ALT level was significantly higher in patients with severe intralobular necro-inflammation activity than in patients with mild or no activity (P = 0.013). However, scores of intralobular activity were only weakly correlated with serum ALT levels (r = 0.27) and could not be used to adequately predict ALT values. Serum ALT levels showed no significant correlation with the scores of portal inflammation, periportal necro-inflammation, total necro-inflammation and fibrosis. Also, there was no significant difference in the mean serum ALT level among different serum HCV-RNA levels and HCV genotypes. Serum HCV-RNA titres and genotypes showed no significant correlation with liver histology and serum HCV-RNA titres were only weakly correlated with the total necro-inflammatory score (r = 0.27). In conclusion, although serum ALT levels were higher in patients with more severe intralobular necro-inflammatory activity, the correlation was not strong enough to adequately predict ALT values. Serum HCV-RNA titres and genotypes also showed no significant correlation with serum ALT levels and liver histologies.

Alanine Transaminase↗
PubMed1998

Gastric myoelectrical activity in patients with cervical spinal cord injury.

OBJECTIVE: Dyspeptic symptoms are common in patients with cervical spinal cord injury (SCI). The supraspinal control of sympathetic innervation to the stomach is interrupted in these patients. Gastric emptying has been reported to be delayed in some patients with cervical SCI. Gastric myoelectrical activity is known to regulate gastric motility and is correlated with gastric emptying. The change in gastric myoelectrical activity after cervical SCI is unknown; our aim was to investigate it. METHODS: The study was performed in 12 cervical SCI patients and 14 healthy controls. Gastric myoelectrical activity was recorded using surface electrogastrography for 30 min in the fasting state and 1 h after a standard test meal. Spectral analysis was performed to compute the following parameters from the electrogastrogram; investigated were the percentage of 2-4 cycles/min (cpm) slow waves, the instability coefficient (IC) of the dominant frequency, the postprandial increment of dominant frequency (deltaF), and its power (deltaP). RESULTS: In both fasting and fed states, regular and stable gastric slow waves were observed in both the control group and patients with cervical SCI. The percentage of normal 2-4 cpm slow waves (preprandial, 80.7+/-3.6% vs 91.5+/-3.7%, p > 0.05; postprandial, 82.0+/-4.4% vs 87.2+/-4.2%, p > 0.05) and IC (preprandial, 0.19+/-0.04% vs 0.28+/-0.05%; postprandial, 0.24+/-0.04% vs 0.27+/-0.02%, p > 0.05) were not significantly different between the two groups. The dominant frequency and its power were also similar between the two groups, no matter whether in the fast (frequency, 2.92+/-0.3 vs 2.93+/-0.06 cpm; power, 30.05+/-1.29 vs 29.08+/-1.23 dB, p > 0.05) or fed (frequency, 3.17+/-0.07 vs 3.02+/-0.06 cpm; power, 32.55+/-0.90 vs 32.07+/-1.18 dB,p > 0.05) state. The postprandial response measured by deltaF (0.25+/-0.09 vs 0.09+/-0.07 cpm, p > 0.05) and deltaP (2.52+/-1.10 vs 2.24+/-1.20 dB, p > 0.05) were also similar between the two groups. CONCLUSION: Gastric myoelectrical activity was not altered after cervical SCI.

Adult↗