Biomedical subjects

J C Wu

Publications and source records attributed to J C Wu.

At least 145 records · Page 8Linked to original sources

PubMed1997

Predicting RNA H-type pseudoknots with the massively parallel genetic algorithm.

MOTIVATION: Using the genetic algorithm (GA) for RNA folding on a massively parallel supercomputer, MasPar MP-2 with 16,384 processors, we successfully predicted the existence of H-type pseudoknots in several sequences. RESULTS: The GA is applied to folding the tRNA-like 3' end of turnip yellow mosaic virus (TYMV) RNA sequence with 82 nucleotides, the 3' UTRs of satellite tobacco necrosis virus (STNV)-2 RNA sequence with 619 nucleotides and STNV-I RNA sequence with 622 nucleotides, and the bacteriophage T2, T4 and T6 gene 32 mRNA sequences with 946, 1340 and 946 nucleotides, respectively. The GA's results match the phylogenetically supported tertiary structures of these sequences.

Algorithms↗

PubMed1997

Experimental study of double-lumen, two-stage endotracheal tube during conventional mechanical ventilation in rabbits.

OBJECTIVE: To evaluate the effects of a double-lumen, two-stage endotracheal tube on gas exchanges (ventilatory efficiency) during conventional mechanical ventilation, using a ventilator in rabbits. DESIGN: Prospective, randomized, crossover laboratory animal trial. SETTING: Research laboratory in the Beijing Children's Hospital. SUBJECTS: Five adult New Zealand rabbits, weighing 3.2 to 3.7 kg. INTERVENTIONS: A new type of endotracheal tube-the double-lumen two-stage endotracheal tube-was designed and tested for ventilation efficiency in rabbits with normal and injured lungs. The new tube (size 3.0 mm) was made out of two Portex endotracheal tubes (size 3.0 mm) by adhering two vertical cross-sections at the distal end of the two tubes. The new tube and a conventional endotracheal tube of the same size (inner diameter 3.0 mm) were randomly used in pressure control ventilation. Each trial was maintained for 30 mins. MEASUREMENTS AND MAIN RESULTS: Effects from the two endotracheal tubes on pulmonary mechanics, hemodynamics, and gas exchange were observed. We measured peak inspiratory pressure, positive end-expiratory pressure (PEEP), intrinsic PEEP, mean airway pressure, and arterial blood and mixed expired gas variables (Pao2, Paco2, pH, and mixed expired gas Pco2). The new endotracheal tube acutely increased CO2 elimination in all animals with normal and injured lungs. Paco2 decreased from 46 +/- 4 to 36 +/- 5 torr (6.1 +/- 0.5 to 4.8 +/- 0.7 kPa; p < .01) in normal lungs and from 48 +/- 5 to 36 +/- 5 (6.4 +/- 0.7 to 4.8 +/- 0.7 kPa; p < .01). Meanwhile, tidal volume fraction decreased from 0.48 +/- 0.07 to 0.35 +/- 0.05 (p < .01) and from 0.56 +/- 0.07 to 0.40 +/- 0.07 (p < .01) in normal and injured lungs, respectively. Intrinsic PEEP of the new tube slightly increased, but there were no significant differences in comparison with the conventional tube. CONCLUSION: Compared with the conventional endotracheal tube, the new double-lumen, two-stage endotracheal tube reduced Paco2 by decreasing anatomical deadspace in rabbits with normal and injured lungs under pressure control ventilation, thus enhancing ventilatory efficiency and reducing ventilator-induced injury.

Animals↗

PubMed1997

A nurse rostering system using constraint programming and redundant modeling.

This paper describes the design and implementation of a constraint-based nurse rostering system using a redundant modeling approach. Nurse rostering is defined as the process of generating timetables for specifying the work shifts of nurses over a given period of time. This process is difficult because the human roster planner has to ensure that every rostering decision made complies with a mixture of hard hospital rules and soft nurse preference rules. Moreover, some nurse shift pre-assignments often break the regularity of wanted (or unwanted) shifts and reduce the choices for other unfilled slots. Soft constraints amount to disjunction, which can be modeled as choices in the search space. This approach, although straightforward, incurs overhead in the search of solution. To reduce search time, we propose redundant modeling, an effective way to increase constraint propagation through cooperations among different models for the same problem. Our problem domain involves around 25 to 28 nurses and 11 shift types. Experiments and pilot testing of the system confirm the effectiveness and efficiency of our method.

Biomedical Engineering↗

PubMed1997

A prospective clinical study of isoniazid-rifampicin-pyrazinamide-induced liver injury in an area endemic for hepatitis B.

In order to evaluate the incidence, predisposing factors and clinical course of antituberculous drug-induced liver injury in hepatitis B surface antigen (HBsAg)-positive carriers and non-carriers, in an area endemic for hepatitis B, we prospectively followed 240 patients (154 male, 86 female; mean age 40 years) who had received daily isoniazid, rifampicin, ethambutol and pyrazinamide for the treatment of pulmonary tuberculosis. Patients with heavy alcohol consumption, with pretreatment serum alanine aminotransferase (ALT) elevation and who had less than 3 months post-treatment follow-up were excluded from the study. Thirty-one (13%) patients were positive for serum HBsAg before treatment. Sixty-three (26%; 95% CI: 21-32%) patients developed antituberculous drug-induced liver injury. The incidence of drug-induced liver injury was significantly more frequent in patients > 35 years of age than in patients < or = 35 years of age (33 vs 17%; P < 0.05), but was not different between HBsAg carriers and non-carriers (29 vs 26%; P > 0.05). Using step-wise logistic regression analysis, patient age > 35 years was the only independent variable for predicting antituberculous drug-induced liver injury, while sex, acetylator phenotype, HBsAg carrier status and severity of tuberculosis were not. The peak serum ALT levels in antituberculous drug-induced liver injury were not significantly different between HBsAg carriers and non-carriers. Only one 61-year-old HBsAg carrier developed severe jaundice after 6 months antituberculous therapy; he subsequently died of hepatic failure. In conclusion, the incidence of antituberculous drug-induced liver injury was significantly higher in patients > 35 years of age than in patients < or = 35 years of age, but was not different between HBsAg carriers and non-carriers. Mortality occurred in an aged HBsAg carrier superimposed with antituberculous drug-induced liver injury.

Adult↗

PubMed1997

Decreasing hepatitis D virus infection in Taiwan: an analysis of contributory factors.

Superinfection of hepatitis D virus (HDV) among hepatitis B virus (HBV) carriers is mainly through heterosexual contact in Taiwan. This study investigated the change of HDV endemicity and its associated contributory factors. Seventy-seven patients with acute HDV superinfection among 527 consecutive exacerbating hepatitis B surface antigen (HBsAg) carriers were identified over the past 12 years. The prevalence decreased significantly by each 3-year period from June 1983 to May 1995 (23.7, 15.5, 13.1 and 4.2%, respectively, P < 0.001). This trend was more significant in the hepatitis B e antigen (HBeAg)-negative group (P < 0.001) than in the HBeAg-positive group (P = 0.073). Subjects with a history of paid sex and prostitutes were also recruited for analysis both in 1989 and 1996. Although not statistically significant, there was a trend showing a decrease in the prevalence of serum antibody against HDV (anti-HDV) in each risk group: it was lower in 1996 among HBsAg-positive brothel-goers (10.3 vs 6.9%), licensed prostitutes (54.5 vs 50%) and unlicensed prostitutes (36.1 vs 30.8%). Accumulation of anti-HDV-positive subjects in risk groups may mask the actual decrease of new HDV-infected cases. The prevalence of the HBsAg carrier rate among all prostitutes has significantly decreased (18.3 vs 12.2%, P = 0.015). The efficacy of each preventive strategy was examined and mapped with the trend. It was concluded that active preventive measures directed against promiscuity and sexually transmitted disease and the promotion of disposable needles may have contributed to the decrease in HDV endemicity.

Adolescent↗

PubMed1997

Hepatocellular carcinoma in the caudate lobe: early diagnosis and active treatment may result in long-term survival.

Hepatocellular carcinoma (HCC) in the caudate lobe is rare and the prognosis of patients with HCC in the caudate lobe has been reported to be poor. Resection for HCC in the caudate lobe has carried a higher rate of surgical risk and early recurrence. The effect of transcatheter arterial embolization (TAE) in treating HCC in the caudate lobe remains unknown. With the wide application of modern diagnostic modalities, we can now detect HCC at an earlier stage for active treatment (surgery or TAE). The aim of the present study was to analyse the effect of different treatments for HCC in the caudate lobe. From 1985 to 1994, 15 patients with HCC in the caudate lobe were retrospectively studied. Another 264 consecutive patients with newly diagnosed HCC treated by TAE were selected as the control group. Two patients underwent surgical resection and survived well without recurrence after 43 and 136 months, respectively. Ten patients underwent TAE and their survival rate was similar to that of the 264 consecutively TAE-treated controls with HCC not in the caudate lobe (P = 0.19). The 1, 3 and 5 year survival rates for TAE-treated patients in the caudate lobe were 67.7, 31.1 and 12.6%, respectively, while in controls these figures were 53.0, 18.4 and 9.1%, respectively. Two of the three patients receiving supportive treatment died within 1 month after diagnosis. Those patients having a smaller solitary tumour without intrahepatic metastasis tended to survive longer. In conclusion, HCC in the caudate lobe does not always indicate a poor prognosis so long as early detection and active treatment (surgery or TAE) are available. Transcatheter arterial embolization may act as an alternative treatment modality for patients with HCC in the caudate lobe.

Adult↗

PubMed1997

Hepatitis B infection and changes in interferon-alpha and -gamma production in patients with systemic lupus erythematosus in Taiwan.

According to previous reports, the prevalence of hepatitis B virus (HBV) infection in patients with systemic lupus erythematosus (SLE) is varied. There has been no report on Taiwan, a hyperendemic area for HBV infection. Furthermore, impaired production of interferon (IFN) in peripheral blood mononuclear cells (PBMC) has been reported to be potentially pathogenic to both chronic HBV infection and SLE. However, the production of IFN in patients with both diseases coexisting is unknown. The aims of this study were to evaluate the prevalence of HBV infection in lupus patients in Taiwan and to measure the production of IFN in patients with both diseases coexisting. One hundred and seventy-three consecutive lupus patients and a control group of 692 age- and sex-matched healthy subjects were included for evaluation of the prevalence of HBsAg. Four groups of subjects (patients with SLE and HbsAg, SLE, chronic hepatitis B and normal controls) were selected for evaluation of the in vitro production of IFN-alpha and -gamma. Six (3.5%) of the 173 SLE patients were positive for HBsAg, which was significantly lower than that of controls (14.7%; P < 0.0001). Patients with coexistent SLE and chronic HBV infection had less lupus activity, including less proteinuria (P = 0.02) and a lower serum titre of anti-double stranded DNA antibodies (anti-dsDNA; P = 0.04), than HBsAg-negative lupus patients. The in vitro production of IFN-alpha in patients with chronic hepatitis B was significantly lower than in those patients with SLE or in the normal control group (P < 0.01). The yields of IFN-alpha and -gamma in patients with coexistent SLE and chronic HBV infection were significantly different from those patients with SLE alone (P < 0.05), but close to those of patients with chronic HBV infection. In conclusion, the prevalence of HBsAg carriers is significantly lower in lupus patients in Taiwan. Patients with coexistent SLE and chronic HBV infection had less lupus activity. Interferon-alpha and -gamma may play a role in the above phenomenon.

Adult↗

PubMed1997

Clinical study of cryoglobulinaemia in Chinese patients with chronic hepatitis C.

Cryoglobulinaemia is the most common immunological disorders seen in patients with chronic hepatitis C virus (HCV) infection. We evaluated the incidence and clinical significance of cryoglobulinaemia in 122 Chinese patients with chronic hepatitis C. The pathogenic roles of HCV genotypes and viraemia in this phenomenon were also evaluated. Fifty-four (44%) of the 122 patients with chronic hepatitis C had cryoglobulinaemia. Eleven (20%) of the patients with cryoglobulinaemia had symptoms and signs of cutaneous vasculitis, arthralgia, neuropathy and renal involvement. The patients with cryoglobulinaemia were predominantly female and had a significantly higher mean serum level of rheumatoid factor and a lower mean serum C4 level compared with patients without cryoglobulinaemia (50 vs 29%, 23 vs 15 IU/mL, 25 vs 31 mg/dL, respectively, P < 0.05). The mean serum HCV RNA level, HCV genotype, the presence of serum auto-antibodies, and the rate of cirrhosis were not significantly different between the two groups. Univariate logistic regression analysis showed female serum levels of alanine aminotransferase (> 90 U/L), rheumatoid factor (> 15 IU/mL), C3c (< 100 mg/dL) and C4 (< 20 mg/dL) to be significant predictors of cryoglobulinaemia in chronic hepatitis C patients. However, multivariate analysis showed only serum C4 levels (< 20 mg/dL) as a significantly independent predictor. We concluded that 44% of Chinese patients with chronic hepatitis C had cryoglobulinaemia. Serum C4 levels were significantly lower in chronic hepatitis C patients with cryoglobulinaemia and the serum C4 level was the only clinical independent predictor associated with this phenomenon. Hepatitis C virus genotype and serum viral load were not clinical independent predictors.

Age Factors↗

PubMed1997

Two proximal activating protein-1-binding sites are sufficient to stimulate transcription of the ovine follicle-stimulating hormone-beta gene.

FSH is an important regulator of mammalian gametogenesis and the female reproductive cycle. Although little is known about the transcriptional regulation of the beta-subunit (the rate-limiting subunit of FSH synthesis), sequence analysis of the ovine FSHbeta promoter has revealed a number of potential activating protein-1 (AP-1; Jun/Fos)-binding sites. To determine whether the gene encoding the beta-subunit of ovine FSH (oFSHbeta) is responsive to AP-1 transcriptional complexes, chimeric constructs containing deleted portions of the oFSHbeta promoter fused to a luciferase reporter were transiently transfected along with c-Jun and c-Fos expression constructs into JAR cells. Analysis of these deletion constructs revealed that the proximal promoter of oFSHbeta is highly stimulated by c-Jun and c-Fos proteins (typically 20-fold with a reporter construct containing oFSHbeta sequences from -215 to +759 bp). This stimulation was lost when a similar construct containing sequences from -84 to +759 bp was tested. Transcriptional start site analysis using reverse transcription-PCR verified that the transcriptional initiation of the -215-bp deletion construct, with or without cotransfected c-Jun/c-Fos, was the same as that observed in vivo. Computer analysis of oFSHbeta sequences from -215 to +1 bp identified four putative AP-1-like elements, located at -155, -120, -83, and -10 bp. Gel retardation experiments using oligonucleotides corresponding to the four putative AP-1-like sites revealed that only -120 and -83 sites in oFSHbeta bound AP-1 proteins in vitro. Site-directed mutagenesis of the -120 and -83 sites showed that each element was required for stimulation by c-Jun and c-Fos proteins as well as 12-O-tetradecanoyl phorbol-13-acetate in transient transfection assays. Finally, immunocytochemical dual labeling was used to show that more than 75% of all FSHbeta-containing cells in ovine pituitary sections from cycling ewes contained nuclear c-Jun, JunB, JunD, and Fos proteins. These data, taken together, show that oFSHbeta transcription can be stimulated by c-Jun and c-Fos proteins via two functionally linked AP-1-like sites in the oFSHbeta proximal promoter and that these sites are likely to be important regulators of FSH production in vivo.

Animals↗

PubMed1997

Prevalence and risk factor analysis of GBV-C/HGV infection in prostitutes.

GB virus-C (GBV-C) and Hepatitis G virus (HGV) are variants of a recently cloned virus transmitted parenterally. It is unclear if sexual contact also transmits this virus. In this study, we detected serum GBV-C/HGV RNA in 140 prostitutes by reverse transcription polymerase chain reaction (RT-PCR) using different primers. Thirty (21%) were found with GBV-C RNA by nested PCR although only 22 (73%) had HGV RNA by single round RT-PCR. Both assays had a nearly perfect agreement (kappa value, 0.812). The prevalence of GBV-C RNA in prostitutes was significantly higher than the control group (30/140 vs. 2/40, P < 0.02). Multivariate analysis revealed that a frequency of paid sex more than 120 times per month was the only factor significantly associated with positive GBV-C RNA in prostitutes (P < 0.003). In summary, prostitutes are a high risk group and reservoir of GBV-C/HGV infection due to high frequency of paid-sex.

Acupuncture Therapy↗

PubMed1997

Clinicopathological comparison of resectable hepatocellular carcinoma between the young and the elderly patients.

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most common cancers in many parts of the world. In Taiwan it is the leading cause of death in male cancer patients. The peak age of onset of HCC varies according to geographic barriers, which indicates different hepatocarcinogenesis among different age groups. This study aims to evaluate whether there exists significantly different clinicopathological features between young and elderly HCC patients. METHODS: During a six-year period, a total of 248 patients with HCC underwent liver curative resection at Veterans General Hospital-Taipei, Taiwan. Among them, 22 patients were younger than 40 years of age, and 43 patients were older than 70 years of age. Important clinicopathological characteristics of the patients (including sex, family history of HCC, smoking habits and alcohol consumption patterns, hepatitis B or C infection, indocyanine-green retention rate at 15 minutes (ICGR-15), serum alpha-fetoprotein value, tumor size, tumor number, tumor venous invasion, capsular formation, tumor staging, cirrhosis, and tumor DNA ploidy) and postresectional prognosis were compared between young and elderly HCC patients. RESULTS: The frequency of presence of family history (22.7% versus 4.7%), hepatitis B surface antigen carrier rate (81.8% versus 48.8%), and patients with large-sized tumors (31.8% versus 7.0%) were significantly higher in young patients than in elderly patients. The male:female ratio (4.5:1 versus 42:1), degree of liver damage (reflected by the ICGR-15 value, 5.6 +/- 5.0% versus 13.1 +/- 8.8%) and the incidences of liver cirrhosis (18.2% versus 48.8%) were significantly lower in young patients than in elderly patients. However, there were no significant differences in postresectional survival rates between these two groups. CONCLUSIONS: There are age-related differences in clinicopathological characteristics of HCC patients. Accordingly, different mechanisms of hepatocarcinogenesis may exist between young and elderly HCC patients.

Adolescent↗

PubMed1996

Structure-activity relationships for inhibition of inosine monophosphate dehydrogenase by nuclear variants of mycophenolic acid.

Structure-activity relationships in the region of the phthalide ring of the inosine monophosphate dehydrogenase inhibitor mycophenolic acid have been explored. Replacement of the lactone ring with other cyclic moieties resulted in loss of potency, especially for larger groups. Replacement of the ring by acyclic substituents also indicated a strong sensitivity to steric bulk. A phenolic hydroxyl group, with an adjacent hydrogen bond acceptor, was found to be essential for high potency. The aromatic methyl group was essential for activity; the methoxyl group could be replaced by ethyl to give a compound with 2-4 times the potency of mycophenolic acid in vitro and in vivo.

Animals↗

PubMed1996

The involvement of PKC in N-cadherin-mediated adherens junction assembly in cultured cardiomyocytes.

Activation of PKC by PMA was shown to promote the separation of chicken cardiomyocytes from each other in culture. Immunofluorescence staining for N-cadherin indicated that PMA, but not its inactive isoform 4 alpha PMA, induces the separation of cardiomyocytes and of co-cultured fibroblasts at intercellular junctional regions. The PMA-induced separation of cardiomyocytes and of co-cultured fibroblasts was inhibited by the PKC inhibitor, H-7. Immunoblot analysis further demonstrated that both PKC iota and PKC lambda were expressed in the cardiomyocyte cultures. While PKC lambda was localized to the cell-cell contact areas between cardiomyocytes, PKC iota was only detectable in the perinuclear cytoplasm of the co-cultured fibroblasts. The present findings suggest the involvement of PKC in regulating N-cadherin-mediated adherens junction formation in chicken cardiomyocytes. The differential distribution of PKC lambda and PKC iota in the cardiomyocytes and in the co-cultured fibroblasts suggests that different PKC isozymes are involved in regulating the assembly of intercellular junctions in these two cell types.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗

PubMed1996

Brain glucose metabolism during non-rapid eye movement sleep in major depression. A positron emission tomography study.

BACKGROUND: Depression is characterized by several sleep-related abnormalities shortly before and after sleep onset, such as prolonged sleep latency, loss of stage 3-4 sleep, reduced rapid eye movement (REM) latency, increased nocturnal core body temperature, and abnormal hormone secretion patterns. Sleep deprivation is associated with a temporary improvement in depression. We hypothesized that depressed patients may be "overaroused" and that absolute cerebral glucose metabolism would be elevated during the first nocturnal non-REM sleep period in depressed patients compared with normal controls. In addition, since hypofrontality (greater metabolic activity in occipital compared with frontal cortical activity) has been reported in waking positron emission tomographic studies of depressed patients compared with controls, we predicted significant hypofrontality in depressed patients during the first non-REM period. METHODS: Positron emission tomography with fludeoxy-glucose F 18 was used to compare 10 unmedicated men with unipolar depression with 12 normal men during the first non-REM sleep period at normal bedtime. RESULTS: Whole-brain absolute metabolic rate during non-REM sleep was significantly elevated (+47%) in patients compared with controls. Mean absolute cerebral glucose metabolic rate was also higher in every area of the brain in patients compared with normal controls. The greatest significant mean increases were in the posterior cingulate and amygdala (+44%), hippocampus (+37% to +43%), occipital and temporal cortex (+33% to +34%), and pons (+33%). Relative metabolic rates in specific neroanatomical areas, however, varied considerably both within the patient group and between patients and controls. Patients showed significant hypofrontality, particularly in the medio-orbital frontal cortex, compared with controls. Patients also showed significant reductions of relative metabolic rate in the anterior cingulate, caudate, and medial thalamus compared with controls. CONCLUSIONS: These findings provide further support for the hyperarousal hypothesis of some types of major depressive disorder. Abnormal patterns of cerebral metabolism during non-REM sleep in depressed patients confirmed earlier waking findings of decreased relative frontal and abnormal limbic metabolic activity and striatal metabolism in association with posterior cortical increases.

Adult↗

PubMed1996

The relationship of adhesion molecules and leukocyte infiltration in chronic tubulointerstitial nephritis induced by puromycin aminonucleoside in Wistar rats.

We studied the expression of adhesion molecules on infiltrating leukocytes and tubular cells in chronic tubulointerstitial nephritis associated with puromycin aminonucleoside (PA) nephrosis. Rats received injections of PA (2 mg/100 g body wt) weekly for the first 3 weeks and every other week thereafter. Rats were killed at 0, 3, 5, 8, and 12 weeks after the start of injections. From the third to the fifth week, the initial infiltrating cells in interstitial tissue were mainly CD4+ T lymphocytes. At the fifth week, ICAM-1, CD44, and hyaluronate were expressed on infiltrating cells in interstitial tissue. At the eighth week, the number of infiltrating cells reached a peak and consisted of T lymphocytes (CD4, CD8) and macrophages (ED1, MHC class II, CD11b, and CD18). The severity of interstitial infiltration was correlated with the degree of proteinuria and with ICAM-1 expression. Our results suggest that CD4+ T lymphocytes may contribute to the production of initial tubular injury. Expression of ICAM-1 helps mononuclear cells migrate to the interstitium. In addition, expression of CD44 and hyaluronate may play important roles in the chronicity of tubulointerstitial nephritis.

Animals↗

PubMed1996

Immunocytochemical demonstration of a new vimentin-associated protein in 3T3 fibroblasts.

Using a xanthophore cytoskeletal preparation as immunogen, we have produced a monoclonal antibody, A2, which recognized a 160 kDa protein in 3T3 fibroblasts. This protein makes up a cytoplasmic filamentous system, which colocalizes with vimentin filaments. When microtubules and actin filaments are dissolved by high salt extraction, staining with antibody A2 is unaffected. Immunoblot analysis confirms that the 160 kDa protein is co-isolated with vimentin during in vivo high salt extraction. Following vinblastine treatment, both the 160 kDa protein and vimentin become localized to perinuclear caps, as do other intermediate filaments and their associated proteins; after vinblastine removal, the immunostaining produced by A2 becomes filamentous. Immunoelectron microscopy demonstrates that antibody A2 stains a filament system with a diameter of about 10 nm. Our observations suggest that the 160 kDa protein may be a new vimentin-associated protein which differs from the intermediate filament-associated proteins previously reported, and is widely distributed in several cell types.

3T3 Cells↗

PubMed1996

Effects of verapamil, propranolol, and procainamide on adenosine-induced negative dromotropism in human beings.

Adenosine, verapamil, propranolol, and procainamide are widely used antiarrhythmic drugs. The interactions among them are still not known in human beings. Adenosine-induced negative dromotropic effects were assessed by rapid bolus injection of adenosine during constant high right atrial pacing in each patient. The initial dose of adenosine was 0.5 mg and was followed by a stepwise increment of 0.5 mg until atrioventricular (AV) nodal block occurred. The negative dromotropic actions of adenosine were examined in the control state and in the following three protocols in three groups of patients: (1) In 12 patients (group 1), intravenous verapamil, 0.15 mg/kg, was given; (2) In 12 patients (group 2), intravenous propranolol, 0.1 mg/kg, was given; and (3) in 10 patients (group 3), intravenous procainamide, 15 mg/kg, was given. The dose-response curves of adenosine on AV nodal conduction were almost identical in the control state and after verapamil, propranolol, or procainamide injection. However, verapamil, in contrast to propranolol, significantly reduced the dose of adenosine required to produce AV nodal block, from 4.4 +/- 0.7 mg to 2.7 +/- 0.3 mg (p < 0.01). Of note, procainamide exerted no significant effects on adenosine-induced negative dromotropism on AV nodal conduction or AV nodal block. In conclusion, the negative dromotropic effects of adenosine are preserved and independent even in the presence of verapamil, propranolol, or procainamide. Both verapamil and propranolol can exhibit additive effects with adenosine in prolonging AV nodal conduction time; however, only verapamil can reduce the dose of adenosine required to produce AV nodal block. This finding indicates that the dose of adenosine may be reduced for patients who have already been treated with verapamil.

Adenosine↗

PubMed1996

Serum levels of interleukin-8 in alcoholic liver disease: relationship with disease stage, biochemical parameters and survival.

BACKGROUND/AIMS: Interleukin-8 (IL-8), a cytokine produced by a host of cells, including monocytes, macrophages, Kupffer cells and hepatocytes, can activate neutrophils. Peripheral neutrophilia and liver neutrophil infiltration are frequently noted in patients with alcoholic liver disease. However, the relationship between IL-8 and different stages of alcoholic liver disease is uncertain. The aim of this study is to determine if a correlation exists between circulating IL-8 levels and biochemical and histological parameters and survival in alcoholic liver disease. METHODS: Serum levels of IL-8 were determined with an enzyme-linked immunosorbent assay in 166 subjects, consisting of 30 healthy controls, 26 patients with non-alcoholic fatty liver, 15 with alcoholic fatty liver, 32 with alcoholic hepatitis, 30 with alcoholic cirrhosis, 28 with chronic hepatitis B and 5 with chronic hepatitis C. RESULTS: Serum IL-8 levels were markedly elevated in patients with alcoholic hepatitis (437 +/- 51 pg/ml) when compared with all other groups (p < 0.05). Levels of IL-8 in patients with alcoholic fatty liver, alcoholic cirrhosis and viral hepatitis were higher than those in controls and in patients with non-alcoholic fatty liver. In addition, IL-8 levels were higher in patients who died (p = 0.007), and correlated with biochemical and histological parameters, and severity of liver injury: serum aspartate aminotransferase, alanine aminotransferase, total bilirubin, prothrombin time, indocyanine green retention ratio, tumor necrosis factor-alpha and peripheral neutrophil count in patients with alcoholic hepatitis. After a 2-year follow up, patients with IL-8 above 479 pg/ml had a higher mortality rate in the alcoholic hepatitis group (p = 0.033). CONCLUSIONS: These findings suggest that IL-8 is activated in alcoholic liver disease, especially in alcoholic hepatitis, and is closely correlated with liver injury. IL-8 levels can reflect the stage and severity of alcoholic liver disease, and may serve as a predictor of survival in patients with alcoholic hepatitis.

Adult↗