Lack of therapeutic effects of gabexate mesilate on the hepatic encephalopathy in rats with acute and chronic hepatic failure

BACKGROUND AND AIM

Inflammation plays a pivotal role in liver injury. Gabexate mesilate (GM, a protease inhibitor) inhibits inflammation by blocking various serine proteases. This study examined the effects of GM on hepatic encephalopathy in rats with acute and chronic liver failure.

METHODS

Acute and chronic liver failure (cirrhosis) were induced by intraperitoneal TAA administration (350 mg/kg/day for 3 days) and common bile duct ligation, respectively, in male Sprague-Dawley rats. Rats were randomized to receive either GM (50 mg/10 mL/kg) or saline intraperitoneally for 5 days. Severity of encephalopathy was assessed by the Opto-Varimex animal activity meter and hemodynamic parameters, mean arterial pressure and portal pressure, were measured (only in chronic liver failure rats). Plasma levels of liver biochemistry, ammonia, nitrate/nitrite, interleukins (IL) and tumor necrosis factor (TNF)-alpha were determined.

RESULTS

In rats with acute liver failure, GM treatment significantly decreased the plasma levels of alanine aminotransferase (P = 0.02), but no significant difference of motor activity, plasma levels of ammonia, IL-1beta, IL-6, IL-10 and TNF-alpha or survival was found. In chronic liver failure rats, GM significantly lowered the plasma TNF-alpha levels (P = 0.04). However, there was no significant difference of motor activity, other biochemical tests or survival found. GM-treated chronic liver failure rats had higher portal pressure (P = 0.04) but similar mean arterial pressure in comparison with saline-treated rats.

CONCLUSIONS

Chronic GM treatment does not have a major effect on hepatic encephalopathy in rats with TAA-induced acute liver failure and rats with chronic liver failure induced by common bile duct ligation.

Evolution of portal-systemic collateral vasopressin response in endotoxemic portal hypertensive rats

Cirrhotic patients with portal hypertension and variceal hemorrhage are vulnerable to endotoxemia. However, the direct influence of endotoxemia on portal-systemic collateral vasculature remains unexplored. In this study, portal hypertension was induced in Sprague-Dawley rats by partial portal vein ligation. On the 7th day after portal vein ligation, at 0.5, 1.5, and 5 h post endotoxin (LPS; Escherichia coli serotype O111:B4, 3 mg/kg, i.p., E0.5, E1.5 and E5, respectively) or saline (control, C0.5, C1.5, and C5, respectively) injection, hemodynamic measurements and concentration-response relationships to arginine vasopressin (AVP; 10(-10)-10(-7) mol/L) in collateral vascular bed were obtained. In another six parallel groups, reverse-transcriptase-polymerase chain reaction of iNOS, eNOS, and endothelin 1 (ET-1) mRNA expressions for splenorenal shunt, the most prominent intra-abdominal collateral vessel, was performed. The results showed that E0.5 had lower perfusion pressure changes to AVP and higher splenorenal shunt eNOS expression than C0.5 group (P < 0.05). Compared with C1.5, tachycardia, higher perfusion pressure changes and enhanced splenorenal shunt iNOS and ET-1 expression were observed in E1.5 group (P < 0.05). In E5, systemic and portal hypotension with markedly enhanced collateral AVP responsiveness and splenorenal shunt iNOS and ET-1 expressions were noted (P < 0.05). In conclusion, vasoactive substances counterregulation participates, at least in part, the time-dependent changes of collateral AVP responsiveness in endotoxemic portal hypertensive rats.

The association between T-wave morphology and life-threatening ventricular tachyarrhythmias in patients with congestive heart failure

BACKGROUND

Whether T-wave morphology descriptors on the 12-lead electrocardiogram (ECG) can predict the occurrence of life-threatening ventricular arrhythmia in patients with advanced congestive heart failure is unclear.

METHODS

Standard 12-lead ECGs were photoscanned and digitized for analysis in 27 heart failure patients with ventricular tachycardia/ventricular fibrillation (VT/VF; study group), as well as in 54 age- and sex-matched heart failure patients without life-threatening ventricular arrhythmia as a control group. Novel T-wave morphology descriptors were compared.

RESULTS

The results showed that the temporal descriptor, the lead dispersion (LD; 426.5 +/- 279.8 vs 189.0 +/- 125.7, P < 0.001), was significantly higher in the study than in the control group. The other T-wave morphology parameters, such as the T-wave morphology dispersion (45.7 +/- 20.1 vs 44.9 +/- 18.6), the total cosine between QRS and T wave (TCRT; -0.4 +/- 0.4 vs -0.5 +/- 0.3), and the normalized T-loop area (NTLA; 0.5 +/- 0.1 vs 0.4 +/- 0.1), were not significantly different between the two groups (all P value > 0.05). After an adjustment for other clinical variables, increased LD (odds ratio: 9.9, 95% confidence interval [CI]: 2.9-33.4, P < 0.001) or decreased NTLA (odds ratio: 0.4, 95% CI: 0.1-1.0, P =0.05) was associated with VT/VF.

CONCLUSION

The novel T-wave morphology analysis may help in identifying heart failure patients at high risk for VT/VF.

Major adverse events, pretransplant assessment and outcome prediction

Liver cirrhosis and portal hypertension pose enormous loss of lives and resources throughout the world, especially in endemic areas of chronic viral hepatitis. Although the pathophysiology of cirrhosis is not completely understood, the accumulating evidence has paved the way for better control of the complications, including gastroesophageal variceal bleeding, hepatic encephalopathy, ascites, hepatorenal syndrome, hepatopulmonary syndrome and portopulmonary hypertension. Modern pharmacological and interventional therapies have been designed to treat these complications. However, liver transplantation (LT) is the only definite treatment for patients with preterminal end-stage liver disease. To pursue successful LT, the meticulous evaluation of potential recipients and donors is pivotal, especially for living donor transplantation. The critical shortage of cadaveric donor livers is another concern. In many Asian countries, cultural and religious concerns further limit the number of the donors, which lags far behind that of the recipients. The model for end-stage liver disease (MELD) scoring system has recently become the prevailing criterion for organ allocation. Initial results showed clear benefits of moving from the Child-Turcotte-Pugh-based system toward the MELD-based organ allocation system. In addition to the MELD, serum sodium is another important prognostic predictor in patients with advanced cirrhosis. The incorporation of serum sodium into the MELD could enhance the performance of the MELD and could become an indispensable strategy in refining the priority for LT. However, the feasibility of the MELD in combination with sodium in predicting the outcome for patients on transplant waiting list awaits actual outcome data before this becomes standard practice in the Asia-Pacific region.

Risk stratification by T-wave morphology for cardiovascular mortality in patients with systolic heart failure

AIMS

The objective was to investigate the prognostic value of T-wave morphology in systolic heart failure patients. T-wave morphology descriptors on standard 12-lead electrocardiograms (ECG) have been shown to have prognostic importance concerning the arrhythmic susceptibility of patients with previous myocardial infarction. However, these descriptors have not been considered with regard to further risk stratification in patients with systolic heart failure.

METHODS AND RESULTS

Patients with systolic heart failure [defined by a left ventricular ejection fraction (LVEF) <50%] were enrolled. Standard digitized 12-lead ECGs were used for analysis of T-wave morphology descriptors [lead dispersion, T-wave morphology dispersion, percentage of the loop area, percentage of the outer area, and the total cosine between QRS and T-wave (TCRT)]. A total of 650 patients with a mean age of 63 +/- 14 years were enrolled and followed-up for 2.7 +/- 1.8 years. The mean LVEF was 36 +/- 9%. During this study, the total mortality rate was 32.7% and cardiovascular mortality rate was 22.3%. A stepwise backward Cox regression analysis showed that cardiovascular mortality was significantly associated with age (P < 0.001), diabetes mellitus (P = 0.022), haemoglobin (P = 0.001), LVEF (P = 0.001), and TCRT (P = 0.003). On the basis of a median TCRT of -0.473 as a cut-off point, a significant difference in cardiovascular mortality was observed from a Kaplan-Meier survival curve (P = 0.01). Total cosine between QRS and T-wave further stratified the risk of LVEF (P = 0.007), age (P = 0.001), haemoglobin (P < 0.001), and diabetes mellitus (P < 0.001) in cardiovascular mortality for these patients.

CONCLUSION

Total cosine between QRS and T-wave may provide further risk stratification for and therefore impact on the prognosis of patients with systolic heart failure.

Bound states of one-, two-, and three-dimensional solitons in complex Ginzburg-Landau equations with a linear potential

We analyze interactions between moving dissipative solitons in one- and multidimensional cubic-quintic complex Ginzburg-Landau equations with a linear potential and effective viscosity. The interactions between the solitons are analyzed by using balance equations for the energy and momentum. We demonstrate that the separation between two solitons forming a bound state decreases with the increase of the slope of the linear potential.

Splanchnic hyposensitivity to glypressin in a hemorrhage-transfused common bile duct-ligated rat model of portal hypertension: role of nitric oxide and bradykinin

BACKGROUND/AIMS

The portal hypotensive effect of vasopressin during hemorrhage is less effective than that during stable condition in cirrhotic patients or experimental portal hypertension (the so-called hyposensitivity phenomenon). Recent studies have demonstrated that constitutive nitric oxide activities and bradykinin in hemorrhage-transfused partially portal vein-ligated rats are responsible, at least partly, for the splanchnic hyposensitivity to glypressin (a long acting vasopressin analogue). This study investigated the relative contribution of nitric oxide synthase isoforms and the role of bradykinin in the pathogenesis of splanchnic hyposensitivity in rats with cirrhosis induced by common bile duct-ligation (BDL).

METHODOLOGY

Five weeks after BDL, systemic and portal hemodynamics were measured in stable or bleeding BDL rats receiving intravenous infusion of glypressin (0.2 mg/kg). In the treatment groups, N(G)-nitro-L-arginine methyl ester (L-NAME, a non-selective nitric oxide synthase inhibitor), L-canavanine (a specific inducible nitric oxide synthase inhibitor) or HOE 140 (a bradykinin B2 receptor antagonist) was administered 45 minutes before the infusion of glypressin. 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 various inhibitors.

RESULTS

Splanchnic hyposensitivity to glypressin was demonstrated in the hemorrhage-transfused BDL rats. The infusion of L-NAME elevated the mean arterial pressure in the bleeding BDL rats without the modulation of portal pressure. The addition of L-NAME or HOE 140, but not L-canavanine, significantly and similarly potentiated the portal-hypotensive effects of glypressin.

CONCLUSIONS

Constitutive nitric oxide synthase and bradykinin play major roles in the development of splanchnic hyposensitivity to glypressin observed in hemorrhage-transfused rats with biliary cirrhosis.

Age, gender, depression, and sexual dysfunction in Taiwan

INTRODUCTION

The effects of age and gender on sexual function have attracted much attention in recent years, though few studies have focused on this issue in Asian populations.

AIMS

The Changes in Sexual Functioning Questionnaire (CSFQ) was used to: (i) assess the differences in sexual functioning between unmedicated outpatients with depressive disorders and healthy volunteers; and (ii) investigate the influences of gender and age on sexual functioning in both groups.

MAIN OUTCOME MEASURES

The CSFQ was used to assess sexual dysfunction.

METHODS

Two groups of subjects, 73 unmedicated patients with depressive disorders and 116 healthy volunteers, were recruited to the study, and changes in their sexual function were assessed using the CSFQ. Subjects' global depressive level and psychiatric morbidity were assessed using the Taiwanese Depression Questionnaire (TDQ) and the Chinese Health Questionnaire (CHQ).

RESULTS

The depressed subjects had significantly lower total CSFQ scores than did the controls. A negative correlation between age and total CSFQ score was found in both genders of depressed patients. Age generally predicted the sum of the CSFQ scores for both genders in the depressed group after controlling for TDQ score; however, a positive correlation between age and total CSFQ score was identified in the female controls. We also found that the S-curve was the best-fit curve for both the male and female controls, the cut-off point for which was the age of 40.

CONCLUSIONS

Our study confirmed that, as a screening tool for clinically significant sexual dysfunction, the CSFQ offered good sensitivity for both the healthy and depressed subjects. In addition, our findings suggested that age and gender differences should be taken into account when measuring sexual satisfaction. It is possible that the age of 40 could be an anchor point in sexual functioning for the female population of Taiwan.

LOUPE-ASSISTED MODIFIED ONE-LAYER VASOVASOSTOMY

Several studies indicate that microsurgical modified one-layer vasovasostomy is comparable to the two-layer anastomosis with respect to patency and pregnancy rates. The objective of this study was to determine the feasibility and result of modified one-layer vasovasostomy under loupe magnification only. Thirty-two patients aged 28 to 64 years (mean 41.3 +/- 6 years) underwent vasovasostomy at CGMH from July 1997 to June 2002, with all operations being a modified on-layer anastomosis created with the aid of a 3 x loupe. The estimated duration of vasectomy ranged from 4 months to 27 years, with a mean of 9.2 +/- 4.8 years. Postoperative semen analysis and pregnancy were examined. Each patient was followed up at 1,4, and 12 weeks postoperatively. The total operation time ranged from 118 to 228 minutes (average 150 +/- 35 minutes). There was no operation-related complication such as hematoma or wound infection. The patency rate was 89% (25/28), and the pregnancy rate at 2 years or more of follow-up was 39% (11/28). The patency and pregnancy rates were similar to those obtained in most studies of microsurgical vasovasostomy. For uncomplicated vasectomy reversal, this simple loupe-assisted modified one-lyer vasovasostomy seems to provide an adequate anastomosis.

HIGH INGUINAL LOUPE-ASSISTED VARICOCELECTOMY FOR SUBFERTILE MEN WITH VARICOCOCELES: TECHNICAL FEASIBILITY, CLINICAL OUTCOMES AND COMPLICATIONS

254 consecutive patients underwent high inguinal loupe-assisted varicocelectomy. All patients had at least a one year history of infertility with abnormal semen parameters and physical examination and/or color Doppler ultrasound proven varicocele. To facilitate the procedure, an x 3.0 loupe was used during spermatic cord dissection near or at level of internal inguinal ring. Semen analysis and physical examination were performed at 3 monthly intervals. No intra-operative complications occurred. The most common post-operative complications were transient scrotal pain and stitch reaction, occurring in 12% and 4% of men, respectively. Only one permanent and two transient hydroceles were observed. Recurrent or persistent varicocele was identified by physical examination and color Doppler in 5 varicocelectomies (1.4%), and by color Doppler only in 6 varicocelectomies (1.7%). Sperm motility increased from 30 +/- 8% to 46 +/- 20%, and sperm concentration. (10(6)/cc) increased from 24 +/- 18 to 41 +/- 28. The one-year pregnancy rate was 37%. High inguinal loupe-assisted varicocelectomy is a safe, simple, and effective treatment for varicocele.

Chronic thalidomide administration enhances vascular responsiveness to vasopressin in portal-systemic collaterals of bile duct-ligated rats

BACKGROUND

Arginine vasopressin (AVP) controls gastroesophageal variceal bleeding, partly due to its vasoconstrictive effect on portal-systemic collaterals. It has been shown that chronic thalidomide treatment decreases portal pressure, attenuates hyperdynamic circulation and inhibits vascular endothelial growth factor (VEGF) and tumor necrosis factor (TNF)-alpha in partially portal vein-ligated rats. This study investigated the effects of chronic thalidomide treatment on portal-systemic collateral vascular responsiveness to AVP in common bile duct-ligated (CBDL) cirrhotic rats.

METHODS

In the first series, CBDL-induced cirrhotic rats received thalidomide (50 mg/kg/day orally) or distilled water (control) from the 35th to 42nd day after ligation. On the 43rd day after ligation, the body weight, mean arterial pressure, portal pressure, and heart rate were measured. An in situ collateral vascular perfusion model was used to obtain the cumulative concentration-response curves of collateral vessels to AVP (10(-10) to 3 x 10(-7) M). Plasma levels of VEGF and TNF-alpha were measured, and expressions of VEGF and TNF-alpha mRNA in the left adrenal veins were also determined. In the second series, the cumulative concentration-response curves of collateral vessels to AVP in CBDL rats with or without thalidomide (10(-5) M) preincubation in the perfusate were obtained.

RESULTS

The thalidomide and control groups were not significantly different in terms of heart rate, mean arterial pressure and portal pressure (p > 0.05). The collateral vascular perfusion pressure change to AVP was significantly enhanced at 10(-8) M after thalidomide treatment (p = 0.041). Compared with the control group, thalidomide-treated rats had significantly lower plasma VEGF levels (p < 0.001), accompanied by an insignificant reduction in plasma TNF-alpha levels (p > 0.05). The expressions of VEGF and TNF-alpha mRNA in the left adrenal veins of thalidomide-treated CBDL rats were not significantly changed compared with those of the control group. In addition, thalidomide did not significantly elicit changes in vascular responsiveness to AVP in collateral vessels of CBDL rats when it was added into the perfusate.

CONCLUSION

In cirrhotic rats, chronic thalidomide treatment improves the portal-systemic collateral vascular responsiveness to AVP, which was partly related to VEGF inhibition.

Vasopressin response and shunting modulation in cirrhotic rats by chronic nitric oxide inhibition

BACKGROUND AND AIM

Nitric oxide (NO) plays a significant role in the vascular hyposensitivity to vasoconstrictors in cirrhosis. Chronic NO inhibition improves the portal-systemic collateral responsiveness to arginine(8)-vasopressin (AVP) and ameliorates shunting degree in rats with prehepatic portal hypertension. This study investigated whether long-term NO inhibition by N(G)-nitro-L-arginine methyl ester (L-NAME) enhances the collateral vascular responsiveness to AVP and alleviates the severity of shunting in cirrhotic rats.

METHODS

Bile duct-ligated (BDL) rats received L-NAME in tap water (25 mg/kg/day) or tap water only (control) for 1 week from the 36th day after BDL. On the 43rd day, the mean arterial pressure and portal pressure were measured. With an in situ perfusion model of portal-systemic collateral vasculature, different concentrations of AVP (10(-10)-10(-7) mol/L) with a constant flow rate (12 mL/min) were applied to assess the perfusion pressure changes of collaterals. In addition, flow pressure curves were obtained with different flow rates (6-18 mL/min): the slopes serve as indices of collateral vascular resistance and the higher resistance indicates less collateral.

RESULTS

The mean arterial pressure was significantly increased after L-NAME treatment (P < 0.05), whereas the heart rate and portal pressure were not significantly modified. As compared with the controls, the L-NAME group exerted significantly higher perfusion pressure changes to AVP at the concentrations of 3 x 10(-8), 10(-7) and 3 x 10(-7) mol/L. In addition, chronic L-NAME administration induced collateral vascular resistance elevation, suggesting the attenuation of portal-systemic shunting.

CONCLUSION

Chronic NO inhibition improves the collateral vascular responsiveness to AVP and ameliorates portal-systemic shunting in BDL cirrhotic rats.

First Report of Onion Bulb Rot Caused by Botrytis aclada in China

During the spring of 2006, onion bulbs with gray mold symptoms on the surface were observed in a few supermarkets in Wuhan, China. Onions mummified as they decayed. Further surveys of five randomly selected batches of onion bulbs in one of the supermarkets indicated that the disease occurred in all batches and the disease incidence ranged from 6 to 50%. Eight diseased onion bulbs were collected arbitrarily and isolations were made using homemade potato dextrose agar (PDA). Single-spore cultures of the isolated Botrytis sp. were established and maintained on PDA plates at 20°C. The 10-day-old PDA cultures of all of these isolates were gray and covered with abundant beige, ovoid- or oblong-shaped conidia, which were budded from terminal ampullae formed on dichotomously branching conidiophores. Conidia from these isolates measured 7.6 to 10.4 μm long and 4.2 to 5.6 μm wide, with an average of 8.4 × 5.0 μm. No sclerotia were produced from any of these PDA cultures after incubation at 20°C for 30 days. Morphological characteristics of colonies and conidia of these isolates were similar to Botrytis aclada according to the description made by Yohalem et al. (3). Inoculation of healthy onion bulbs with one of the eight fungal strains, OnionBc-15, resulted in gray mold symptoms similar to those observed in the supermarkets. Microscopic examinations showed that the size and shape of conidia that formed on the surface of diseased bulbs of onion were identical to the size and shape of conidia of OnionBc-15, indicating that this isolate can cause onion bulb rot. The isolate OnionBc-15 was further characterized by molecular techniques. Genomic DNA was extracted from mycelia of this strain and used as a template for amplification of two previously reported DNA regions, the internal transcribed spacer (ITS) region of the ribosomal RNA genes and the L45-550 sequence (1), which can be used to distinguish B. aclada and two closely related species, B. allii and B. byssoidea (3). Universal primers ITS1 and ITS4 were used to amplify the ITS region (2). A 539-bp DNA sequence was generated, cloned, and sequenced (GenBank Accession No. EU093077). The sequence contained two SphI restriction sites and was 99% identical in nucleotides to that of B. aclada strain PRI006 (GenBank Accession No. AJ716295). It is different from B. allii and B. byssoidea, which have only one SphI restriction site for the ITS1/ITS4-amplified DNA sequence (2). The Botrytis-specific primers, BA2f and BA1r, were used to amplify the L45-550 sequence (2). A 413-bp DNA sequence was generated, cloned, and sequenced. The sequence did not contain any ApoI restriction sites. This is also similar to B. aclada, but different from B. allii and B. byssoidea, which contains one ApoI restriction site in the BA2f/BA1r-amplified DNA sequence (2,3). On the basis of morphological characteristics and the two molecular features, it is concluded that the isolate OnionBc-15 belongs to B. aclada. To our knowledge, this is the first report on the occurrence of B. aclada causing onion bulb rot in China. References: (1) K. Nielsen and D. S. Yohalem. Mycologia 93:264, 2001. (2) K. Nielsen et al. Plant Dis. 86:682, 2002. (3) D. S. Yohalem et al. Mycotaxon 85:175, 2003.

Simvastatin for rats with thioacetamide-induced liver failure and encephalopathy

BACKGROUND AND AIM

Nitric oxide (NO) inhibition aggravates hepatic damage and encephalopathy and increases mortality in rats with thioacetamide (TAA)-induced acute liver failure. Statins enhance NO synthase expression beyond their lipid-lowering capability, but the impact on encephalopathy remains unexplored. The aim of this study was to assess the effects of simvastatin on rats with TAA-induced acute liver damage and hepatic encephalopathy.

METHODS

Sprague-Dawley rats received TAA (350 mg/kg/day) or normal saline (NS) by intraperitoneal injection for 3 consecutive days. Two days before injections, each group was divided into three subgroups, taking (i) distilled water; (ii) simvastatin (20 mg/kg/day); or (iii) simvastatin plus N(G)-nitro-l-arginine methyl ester (L-NAME, 25 mg/kg/day) by oral gavage for 5 days. On the fifth day, severity of encephalopathy was assessed and plasma levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin and ammonia were measured.

RESULTS

The TAA subgroups showed higher ALT, AST, bilirubin and ammonia levels and lower motor activity counts as compared with the NS subgroups. Among the TAA-treated subgroups, rats with simvastatin treatment exerted higher motor activity counts and survival rate (P = 0.043), and a trend of lower ALT, AST, bilirubin and ammonia levels than those receiving saline. All rats that underwent simvastatin plus L-NAME treatment died during or after TAA injections.

CONCLUSIONS

Simvastatin improved encephalopathy and survival in TAA-administered rats. The beneficial effect was offset by L-NAME, suggesting the role of NO in liver damage and encephalopathy.

Validation and comparison of alcohol-screening instruments for identifying hazardous drinking in hospitalized patients in Taiwan

AIM

The aim of this study was to validate the Mandarin Chinese version of different screening instruments and compare their performances for identifying hazardous drinkers in Taiwan.

METHODS

We compared the performance of the Mandarin Chinese versions of AUDIT, AUDIT-C (AUDIT items 1, 2 and 3), AUDIT-4 (AUDIT items 1, 2, 3 and 10), AUDIT-3 (AUDIT item 3), TWEAK, SMAST and CAGE to detect hazardous drinking in hospitalized patients in Taiwan. The results of the test instruments were blindly compared with the reference standard Schedule for Clinical Assessments in Neuropsychiatry (SCAN).

RESULTS

Of 404 patients evaluated, 100 were identified as having a hazardous drinking pattern. All screening instruments showed acceptable sensitivities (ranging from 85 to 93%) and specificities (ranging from 72 to 92%), but AUDIT and its short forms performed consistently better than the other instruments.

CONCLUSIONS

The Mandarin Chinese versions of AUDIT and its derivatives perform well in screening hospitalized Taiwanese patients for hazardous drinking.

Genetic distinctions and clinical characteristics of type 1 autoimmune hepatitis in Taiwan

BACKGROUND/AIMS

The genetic features in Eastern autoimmune hepatitis (AIH) patients are seldom surveyed. Previous studies on the linking of human leukocyte antigen (HLA) with AIH have highlighted the necessity of evaluating ethnically homogeneous populations, but no investigation for Taiwanese patients has been reported. This study aims to evaluate the HLA characteristics of Taiwanese AIH patients.

METHODOLOGY

Medical records of Taiwanese AIH patients (1990-2005) were reviewed and the correlation of HLA alleles with disease susceptibility and severity was surveyed. HLA typing was performed by polymerase chain reaction amplification with sequence-specific primers.

RESULTS

Unlike the Western reports, HLA-A1, B8, and DR3 were not identified. The most frequently encountered was A11 (48.6%). DR4 (35.1%) was less often found than that in Japanese and Chinese series. As compared with Taiwanese normal controls, the frequency of B35 was significantly increased (18.9% vs. 5.4%, odds ratio = 4.072, Pc < 0.001). B35-postitive patients also had higher pretreatment serum aminotransferase concentrations. More of the patients were cholestatic and responded well to a lower dose of prednisolone as compared with those reported in the Western literature.

CONCLUSIONS

HLA-B35 plays a distinct role in susceptibility and severity of AIH in Taiwan. Racial genetic backgrounds may account for the different results.

Chronic indomethacin treatment enhances the portal-systemic collateral vascular response to vasopressin in bile-duct ligated rats

BACKGROUND

Liver cirrhosis is often accompanied by portal-systemic collateral formation with hemorrhage and encephalopathy. Prostacyclin participates in hyperdynamic circulation and vascular hyporeactiveness to vasoconstrictors in cirrhosis. It has been shown that arginine vasopressin (AVP) induces direct collateral vasoconstriction in portal hypertensive rats, which is potentiated by indomethacin preincubation. However, the influence of chronic indomethacin administration in cirrhosis remains unexplored.

METHODS

This study was performed on male Sprague-Dawley rats with liver cirrhosis induced by common bile duct ligation. They received subcutaneous indomethacin (5 mg/kg/day) or distilled water (control) injection from the 36th to 42nd day after operation. On the 43rd day, systemic and portal hemodynamics were evaluated and the following experiments were performed with an in situ collateral perfusion model: in the first series, concentration-response curves to AVP (10(-10) to 10(-7) M) were obtained; in the second series, flow-pressure curves were plotted (Krebs solution, 6-18 mL/min), where the slope represents an index of collateral vascular resistance (the higher the resistance, the smaller the amount of shunting vessels, that is, the lower the degree of shunting).

RESULTS

The mean arterial pressure and portal pressure were similar between indomethacin and control groups (p > 0.05). Indomethacin elevated the collateral perfusion pressure to AVP (3 x 10(-9), 10(-8) M, p < 0.05) but did not influence the slope of the flow-pressure curve (p > 0.05).

CONCLUSION

In bile duct-ligated cirrhotic rats, indomethacin improves the portal-systemic collateral vascular responsiveness to AVP without alleviating the severity of shunting.

Controlled trial of problem-solving therapy and consultation-liaison for common mental disorders in general medical settings in Taiwan

OBJECTIVE

Common mental disorders (CMD) are prevalent high-impact illnesses seen in general medical settings worldwide. There has been no investigation on the efficacy of enhanced care in Chinese societies. The aim of this study was to compare the outcome of three interventions for treating CMD: usual care (UC), problem-solving therapy plus UC (PST-UC), and psychiatric consultation plus UC (PC-UC).

METHOD

The sample for this randomized controlled trial consisted of 254 patients with CMD being managed in general medical care settings. Clinical and functional assessments were done at baseline and at 16 weeks.

RESULTS

Two hundred six patients had complete data at 16 weeks (66 in the UC group, 63 in the PST-UC group, 77 in the PC-UC group). All patients had significant improvement on all scales over time, with no significant differences among the three treatment groups.

CONCLUSION

This trial failed to demonstrate the efficacy of enhanced care with consultation-liaison by mental health professionals for patients with CMD in general medical settings in Taiwan. Improved outcomes may require more integrated interventions.

Imaging of human aortic atherosclerotic plaques by polarization-sensitive optical coherence tomography

Optical coherence tomography (OCT) is analogous to ultrasound imaging except that it uses infrared light instead of sound. Polarization-sensitive optical coherence tomography (PS-OCT) combines the advantages of OCT and provides additional image contrast of the tested sample. We demonstrate this technique for imaging of back-reflected light, birefringence, and fast-axis orientation simultaneously in different kinds of atherosclerosis plaque. This in vitro study suggests birefringence changes in plaque are due to the prominent deposition of collagen or cholesterol by correlating PS-OCT images with histology. Thus the combination of high resolution structural imaging and birefringence detection make PS-OCT a potentially powerful tool for early assessment of atherosclerosis appearance and prediction of plaque rupture.

Role of hepatic nitric oxide synthases in rats with thioacetamide-induced acute liver failure and encephalopathy

BACKGROUND

Hepatic encephalopathy is neuropsychiatric derangement secondary to hepatic decompensation or portal-systemic shunting. Nitric oxide (NO) synthase inhibition aggravates encephalopathy and increases mortality in rats with thioacetamide (TAA)-induced acute liver failure, suggesting a protective role of NO. This study investigated the roles of endothelium-derived constitutive NO synthase (eNOS) and inducible NOS (iNOS) in the liver of rats with fulminant hepatic failure and encephalopathy.

METHODS

Male Sprague-Dawley rats (300-350 g) were randomized to receive TAA 350 mg/kg/day, by intraperitoneal injection or normal saline for 3 days. Severity of encephalopathy was assessed with the Opto-Varimex animal activity meter. Plasma levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase, and bilirubin were measured. Hepatic iNOS and eNOS RNA and protein expressions were assessed by reverse transcription-polymerase chain reaction and Western blot analyses, respectively.

RESULTS

The TAA group showed lower motor activity counts than the normal saline group. Hepatic eNOS, but not iNOS, mRNA and protein expressions were enhanced in the TAA group. In addition, hepatic eNOS mRNA expression was negatively correlated with total movement but positively correlated with ALT and AST. Protein expression of hepatic eNOS was positively correlated with ALT, AST and bilirubin.

CONCLUSION

Upregulation of hepatic eNOS was observed in rats with TAA-induced fulminant hepatic failure and encephalopathy, which might play a regulatory role.

Chronic cyclooxygenase blockade enhances the vasopressin responsiveness in collaterals of portal hypertensive rats

OBJECTIVE

Collateral vascular responsiveness to vasoconstrictors may be crucial in the management of acute variceal bleeding. In an in situ perfusion model, arginine vasopressin (AVP) has been shown to cause a direct vasoconstrictive effect on portal-systemic collaterals and this effect is enhanced by preincubation of indomethacin (INDO). The purpose of this study was to investigate the effects of chronic INDO administration on the portal-systemic collateral responsiveness to AVP and the degree of portal-systemic shunting in portal hypertensive rats.

MATERIAL AND METHODS

Rats with partial portal vein ligation randomly received daily subcutaneous injections with INDO (5 mg/kg) or distilled water (control group) 2 days prior to until 7 days after ligation. Systemic and portal hemodynamics was evaluated on the 8th day. Using an in situ collateral perfusion model, AVP (10(-10)-10(-7) M) at a constant flow rate (20 ml/min) was applied. In another series, Krebs solution with different flow rates (5-30 ml/min) was used to obtain flow-pressure curves: the slopes represent collateral vascular resistances--the higher resistances indicate fewer collaterals.

RESULTS

Mean arterial pressure and portal pressure were not significantly different between the INDO-treated group and the control group (p>0.05). In the first series of experiments, INDO treatment increased the collateral perfusion pressure to AVP at 10(-8) M, 3x10(-8) M, and 10(-7) M (p<0.05). In the second series, INDO did not change collateral vascular resistance, which suggests that the degree of shunting was not altered.

CONCLUSIONS

Chronic INDO treatment improves the collateral vascular responsiveness to AVP without ameliorating portal-systemic shunting in portal hypertensive rats.

Methimazole alleviates hepatic encephalopathy in bile-duct ligated cirrhotic rats

BACKGROUND

Acute or chronic liver damage may lead to hepatic encephalopathy. Previous studies have indicated the hemodynamic and hormonal mimicry between portal hypertension and hyperthyroidism. Furthermore, medically or surgically induced hypothyroidism has been found to be beneficial in ameliorating hyperdynamic circulation in the portal hypertensive state and in alleviating acute or chronic liver injury in rats. However, the effect of chronic thyroid hormone inhibition on chronic hepatic encephalopathy in cirrhosis remains unknown.

METHODS

Liver cirrhosis was induced by bile-duct ligation (BDL) in male Sprague-Dawley rats. Three weeks after BDL, rats were randomized to receive either tap water (control) or 0.04% methimazole in drinking water for 3 weeks. At the end of 6 weeks after BDL, severity of encephalopathy was assessed by the Opto-Varimex animal activity meter and hemodynamic parameters were measured. Blood samples were collected for determination of thyroid stimulating hormone, ammonia and liver biochemistry.

RESULTS

The heart rate of the methimazole-treated group was significantly lower than that of the control group (p = 0.015), whereas there were no differences in the mean arterial pressure and portal pressure. The total amount of movements were significantly increased in the methimazole group (p = 0.029). Plasma levels of ammonia, aspartate aminotransferase and alkaline phosphatase were significantly lower (p = 0.01) and thyroid stimulating hormone significantly higher (p = 0.035) in the methimazole group.

CONCLUSION

Chronic methimazole treatment alleviates hepatic encephalopathy and liver damage in rats with BDL-induced hepatic cirrhosis.