Lipopolysaccharide enhanced renal vascular response to endothelin-1 through ETA overexpression in portal hypertensive rats

BACKGROUND AND AIM

Hypo-perfusion resulting from intense renal vasoconstriction is traditionally contributed to renal dysfunction in advanced liver disease, although cumulative studies demonstrated renal vasodilatation with impaired vascular contractility to endogenous vasoconstrictors in portal hypertension and compensated liver cirrhosis. The pathophysiology of altered renal hemodynamics remains unclear. This study, using a rat model of portal hypertension with superimposed endotoxemia, was designed to delineate the evolution of renal vascular reactivity and vaso-regulatory gene expression during liver disease progression.

METHODS

Rats were randomized into sham surgery (SHAM) or partial portal vein ligation (PVL). Endotoxemia was induced by intraperitoneal injection of lipopolysaccharide (LPS) on the seventh day following surgery. Isolated kidney perfusion was performed at 0.5 h or 5 h after LPS to evaluate renal vascular response to endothelin-1.

RESULTS

In contrast to impaired vascular contractility of SHAM rats, PVL rats displayed enhanced renal vascular reactivity to endothelin-1 at 5 h following endotoxemia. There were extensive upregulations of inducible nitric oxide synthase in kidney tissues of endotoxemic rats. The changes of renal endothelin receptor type A (ETA ) level paralleled with the changes of renal vascular reactivity in LPS-treated rats. Compared with SHAM rats, PVL rats showed increased renal ETA and phosphorylated extracellular-signal-regulated kinases 1/2 (p-ERK1/2) at 5 h after LPS.

CONCLUSION

LPS-induced systemic hypotension induces a paradoxical change of renal vascular response to endothelin-1 between SHAM and PVL rats. LPS-induced renal vascular hyperreactivity in PVL rats was associated with upregulation of renal ETA and subsequent activation of ERK1/2 signaling.

Risk of Parkinson's disease following zolpidem use: a retrospective, population-based cohort study

OBJECTIVE

To evaluate the influence of long-term zolpidem use on the incidence of developing Parkinson's disease.

METHOD

2,961 subjects who used zolpidem for the first time longer than 3 months between 1998 and 2000 were identified in the National Health Insurance system of Taiwan. Subjects without a history of zolpidem use were randomly selected as a comparison cohort and frequency matched to zolpidem users based on age, sex, and index date. The diagnosis of Parkinson's disease was based on the criteria of the International Classification of Diseases, Ninth Revision, Clinical Modification. Its incidence until the end of 2009 was calculated and its hazard ratios (HRs) and 95% CIs were estimated using Cox proportional hazards regression models and Kaplan-Meier analysis.

RESULTS

The overall incidence of Parkinson's disease was greater among zolpidem users than in the comparison cohort (HR = 1.88; 95% CI, 1.45-2.45). However, there was no difference in Parkinson's disease incidence between these 2 cohorts after 5 years of observation. The risk of Parkinson's disease increased with increasing zolpidem dose, with an HR of 0.70 for low-dose users (< 400 mg/y) and 2.94 for high-dose users (≥ 1,600 mg/y). The incidence of Parkinson's disease was greater in subjects using zolpidem only (HR = 2.35; 95% CI, 1.66-3.33) compared to those using benzodiazepines only (HR = 1.31; 95% CI, 0.91-1.90). By stratified analysis, zolpidem use with concurrent depression (HR = 4.79) increased the risk of Parkinson's disease compared to that of zolpidem users without concurrent depression.

CONCLUSIONS

Zolpidem use might unmask preclinical Parkinson's disease, especially in patients with depression. However, large population-based, unbiased, randomized trials are warranted to confirm this finding.

Multi-scale symbolic entropy analysis provides prognostic prediction in patients receiving extracorporeal life support

INTRODUCTION

Extracorporeal life support (ECLS) can temporarily support cardiopulmonary function, and is occasionally used in resuscitation. Multi-scale entropy (MSE) derived from heart rate variability (HRV) is a powerful tool in outcome prediction of patients with cardiovascular diseases. Multi-scale symbolic entropy analysis (MSsE), a new method derived from MSE, mitigates the effect of arrhythmia on analysis. The objective is to evaluate the prognostic value of MSsE in patients receiving ECLS. The primary outcome is death or urgent transplantation during the index admission.

METHODS

Fifty-seven patients receiving ECLS less than 24 hours and 23 control subjects were enrolled. Digital 24-hour Holter electrocardiograms were recorded and three MSsE parameters (slope 5, Area 6-20, Area 6-40) associated with the multiscale correlation and complexity of heart beat fluctuation were calculated.

RESULTS

Patients receiving ECLS had significantly lower value of slope 5, area 6 to 20, and area 6 to 40 than control subjects. During the follow-up period, 29 patients met primary outcome. Age, slope 5, Area 6 to 20, Area 6 to 40, acute physiology and chronic health evaluation II score, multiple organ dysfunction score (MODS), logistic organ dysfunction score (LODS), and myocardial infarction history were significantly associated with primary outcome. Slope 5 showed the greatest discriminatory power. In a net reclassification improvement model, slope 5 significantly improved the predictive power of LODS; Area 6 to 20 and Area 6 to 40 significantly improved the predictive power in MODS. In an integrated discrimination improvement model, slope 5 added significantly to the prediction power of each clinical parameter. Area 6 to 20 and Area 6 to 40 significantly improved the predictive power in sequential organ failure assessment.

CONCLUSIONS

MSsE provides additional prognostic information in patients receiving ECLS.

Activation of N-methyl-D-aspartate receptor glycine site temporally ameliorates neuropsychiatric symptoms of Parkinson's disease with dementia

AIM

We have previously found that sarcosine, a glycine transporter I inhibitor, can improve the psychiatric symptoms of schizophrenia. In this study, we aimed to investigate whether the agent can also ameliorate neuropsychiatric symptoms of Parkinson's disease (PD) patients with dementia.

METHODS

An 8-week, double-blind, placebo-controlled trial was conducted in patients who had PD with dementia (PD-D). Neuropsychiatric manifestations were measured before and at week 2 (V1), week 4 (V2) and week 8 (V3) after treatment. Linear regression with the generalized estimating equations was applied for data analysis.

RESULTS

Fifteen patients were randomized into a sarcosine group; the other 15 into a placebo group. The generalized estimating equations model revealed significant differences in Hamilton Depression Rating Scale score (P = 0.049) at V1 and Neuropsychiatry Inventory (P = 0.039) at V2 between the treatment and placebo groups. By excluding the advanced patients from analysis, there were significant differences in Unified Parkinson's Disease Rating Scale V2 (P = 0.004) and V3 (P = 0.040), Hamilton Depression Rating Scale V1 (P = 0.014) and V2 (P = 0.047), Neuropsychiatry Inventory V1 (P = 0.002) and V2 (P < 0.001) and Behavior Pathology in Alzheimer's Disease Rating Scale V2 (P = 0.025) in favor of sarcosine.

CONCLUSION

Sarcosine temporally improved depression and neuropsychiatric symptoms in PD-D patients without exacerbating the motor or cognitive features; the beneficial effects were more prominent in patients with mild-moderate severity. Enhancement of N-methyl-D-aspartate receptor-glycine cascade may lead to a novel path for the management of PD-D.

Adrenal dysfunction in portal hypertensive rats with acute hemorrhage

Nitric oxide (NO) participates in shock and poorer portal hypotensive effect to vasoconstrictors in portal hypertension with hemorrhage, the so-called splanchnic hyposensitivity. Relative adrenal insufficiency accompanies hemorrhagic shock and is found in liver disease, the ‘hepatoadrenal syndrome’, but the relevant interactions remain unsettled. Portal hypertensive rats were induced by partial portal vein ligation (PVL). Experiments were performed on the 14^th day post PVL: (I) ACTH stimulation test for rats without or with hemorrhage; (II) Glypressin response (mean arterial pressure, MAP; portal pressure, PP) in rats (a) without hemorrhage or with hemorrhage, injected with (b) distilled water (DW), (c) dexamethasone 3 mg/kg; (III) To survey the dose-dependent effects of glucocorticoid without being confounded by endogenous adrenal hormone, glypressin response was surveyed in PVL rats with adrenalectomy: (a) without hemorrhage or with hemorrhage, injected with (b) DW; (c) dexamethasone 3 mg/kg; (d) dexamethasone 5 mg/kg. Plasma tumor necrosis factor-α (TNF-α) concentrations and abdominal aorta (AA), superior mesenteric artery (SMA) NO synthases (NOS) mRNA expressions were determined. The results showed that ACTH induced corticosterone release similarly in PVL rats with or without hemorrhage. In bleeding PVL rats, dexamethasone (1) down-regulated AA NOS and enhanced glypressin-induced MAP elevation; (2) did not influence glypressin-induced PP reduction; (3) reduced TNF-α. In bleeding PVL and adrenalectomized rats, high-dose dexamethasone (1) down-regulated AA/SMA NOS; (2) enhanced glypressin-induced MAP elevation and PP reduction; (3) reduced TNF-α. In conclusion, bleeding portal hypertensive rats failed to enhance corticosterone release, suggesting a relative adrenal insufficiency. High-dose dexamethasone reversed systemic hypotension and splanchnic hyporesponsiveness to glypressin in adrenalectomized PVL rats accompanied by TNF-α and NOS down-regulation, suggesting the importance of adequate adrenocorticoid supplement in portal hypertension with hemorrhage and adrenal dysfunction.

Validation of the Chinese SAD PERSONS Scale to predict repeated self-harm in emergency attendees in Taiwan

BACKGROUND

Past and repeated self-harm are long-term risks to completed suicide. A brief rating scale to assess repetition risk of self-harm is important for high-risk identification and early interventions in suicide prevention. The study aimed to examine the validity of the Chinese SAD PERSONS Scale (CSPS) and to evaluate its feasibility in clinical settings.

METHODS

One hundred and forty-seven patients with self-harm were recruited from the Emergency Department and assessed at baseline and the sixth month. The controls, 284 people without self-harm from the Family Medicine Department in the same hospital were recruited and assessed concurrently. The psychometric properties of the CSPS were examined using baseline and follow-up measurements that assessed a variety of suicide risk factors. Clinical feasibility and applicability of the CSPS were further evaluated by a group of general nurses who used case vignette approach in CSPS risk assessment in clinical settings. An open-ended question inquiring their opinions of scale adaptation to hospital inpatient assessment for suicide risks were also analyzed using content analysis.

RESULTS

The CSPS was significantly correlated with other scales measuring depression, hopelessness and suicide ideation. A cut-off point of the scale was at 4/5 in predicting 6-month self-harm repetition with the sensitivity and specificity being 65.4% and 58.1%, respectively. Based on the areas under the Receiver Operating Characteristic curves, the predictive validity of the scale showed a better performance than the other scales. Fifty-four nurses, evaluating the scale using case vignette found it a useful tool to raise the awareness of suicide risk and a considerable tool to be adopted into nursing care.

CONCLUSIONS

The Chinese SAD PERSONS Scale is a brief instrument with acceptable psychometric properties for self-harm prediction. However, cautions should be paid to level of therapeutic relationships during assessment, staff workload and adequate training for wider clinical applications.

Space electric field concentrated effect for Zr:SiO2 RRAM devices using porous SiO2 buffer layer

To improve the operation current lowing of the Zr:SiO2 RRAM devices, a space electric field concentrated effect established by the porous SiO2 buffer layer was investigated and found in this study. The resistive switching properties of the low-resistance state (LRS) and high-resistance state (HRS) in resistive random access memory (RRAM) devices for the single-layer Zr:SiO2 and bilayer Zr:SiO2/porous SiO2 thin films were analyzed and discussed. In addition, the original space charge limited current (SCLC) conduction mechanism in LRS and HRS of the RRAM devices using bilayer Zr:SiO2/porous SiO2 thin films was found. Finally, a space electric field concentrated effect in the bilayer Zr:SiO2/porous SiO2 RRAM devices was also explained and verified by the COMSOL Multiphysics simulation model.

Selective cyclooxygenase-1 inhibition improves collateral vascular reactivity in biliary cirrhotic rats

BACKGROUND

Evidence has demonstrated that overproduction of prostacyclin (PGI2) is critical in the pathogenesis of splanchnic hyposensitivity to vasoconstrictors in the cirrhotic state. The biosynthesis of PGI2 is through cyclooxygenase (COX). This study evaluated which isoform of COX is dominant in the mechanism of collateral vascular reactivity of biliary cirrhotic rats.

METHODS

Three groups of formalin-injected common bile duct-ligated (FBDL) induced cirrhotic rats received two doses of: (1) selective COX-1 inhibitor (SC-560 2 mg/kg); (2) COX-2 inhibitor (NS-398 2 mg/kg); (3) dimethyl sulfoxide (control). Subsequently, the rats were kept in metabolic cages for 24 hours to collect urine. Thereafter, the systemic and portal hemodynamics and renal function were measured. In another series, using in-situ collateral perfusion model, the collateral vascular responses to arginine vasopressin (AVP) were measured in the subject rats after preincubation of vehicle (Krebs solution), SC-560 (5 μM) or NS-398 (10 μM).

RESULTS

The mean arterial pressure, heart rate, and portal pressure were similar among SC-560-treated, NS-398-treated, and control groups. Additionally, there was no significant difference in the calculated creatinine clearance rates among these three groups. SC-560 preincubation significantly enhanced the pressor effect of AVP at the concentration of 3M × 10(-9) M (11.0 ± 1.0 mmHg vs. 6.4 ± 0.6 mmHg, p = 0.002) in the cirrhotic rats.

CONCLUSION

There was no significant hemodynamic change and renal toxicity after acute administration of COX inhibitor in the FBDL-induced cirrhotic rats. Preincubation of selective COX-1, but not COX-2, inhibitor could enhance collateral vascular response to AVP, indicating that COX-1 plays a major role in the collateral vascular reactivity.

The impact of abnormal muscle tone from hemiplegia on reclining wheelchair positioning: a sliding and pressure evaluation

BACKGROUND

Little is known about the influence of existing muscle tone abnormality on the sitting posture of stroke patients in reclining wheelchairs.

AIM

To investigate the impact of muscle tone abnormality from hemiplegia on the forward sliding and pressure of stroke patients while sitting in reclining wheelchairs.

DESIGN

Experimental study.

SETTING

The Assistive Devices/Technology Center at the Rehabilitation Department of hospital.

POPULATION

14 able-bodied elders and nonambulatory elderly stroke patients with flaccid (N.=12) or spastic hemiplegia (N.=13) participated in this study. Of the 12 patients with flaccid hemiplegia, 8 suffered from left-sided hemiplegia and 4 from right-sided hemiplegia. Of the 13 patients with spastic hemiplegia, 6 suffered from left-sided hemiplegia and 7 from right-sided hemiplegia.

METHODS

We performed 3 reclining cycles in wheelchairs with conventional seats and V-shaped seats for each participant. The sliding along the backrest (BS) plane and the seat (SS) plane, mean sitting pressure (MP), and sacral peak pressure (SPP) of the participants were recorded. The Kruskal-Wallis test was used to compare the difference in BS, SS, MP, and SPP between able-bodied elders and stroke patients.

RESULTS

The BS, SS, and SPP during repetitive reclining were generally greatest in flaccid hemiplegic participants, followed by spastic hemiplegic participants, and finally by able-bodied participants. There was no significant difference in MP among three subject groups on both conventional seats and V-shaped seats in most comparisons. Able-bodied participants' buttocks tended to slide forward on conventional seats but backward on V-shaped seats, whereas hemiplegic participants' buttocks slid forward on both seat types.

CONCLUSION

Stroke patients with flaccid hemiplegia are the most vulnerable to sacral sitting and higher sacral pressure in reclining wheelchairs, followed by patients with spastic hemiplegia. There is a difference in the displacement pattern between participants with normal muscle tone and those with abnormal muscle tone during wheelchair positioning. People who have hemiplegia with spasticity do not have incremental forward sliding with repetitive reclining in the same way as those who have a flaccid hemiplegia.

CLINICAL REHABILITATION IMPACT

The findings are valuable for wheelchair prescription and caregiver education.

Development of a Semiselective Medium for Detection of Nalanthamala psidii, Causal Agent of Wilt of Guava

Guava wilt, caused by Nalanthamala psidii, has become an important disease of guava (Psidium guajava) in Taiwan since the 1970s. This study was conducted to develop a semiselective medium for detecting N. psidii in soil and in tissues of diseased guava trees. Among 9 carbon and 21 nitrogen compounds tested in a modified Czapek-Dox medium, the most effective carbon and nitrogen sources for mycelial growth of N. psidii were sucrose and glycine, respectively. Among eight fungicides tested, iprodione at 5 μg ml^-1 and azoxystrobin at 1 μg ml^-1 were the most effective fungicides for detection of N. psidii in artificially infested soil or in naturally infected guava debris. Based on the requirement for carbon and nitrogen sources and response to fungicides, a semiselective medium designated as modified sucrose-glycine semiselective medium (mSGSSM) was developed for isolation of N. psidii, using the modified Czapek-Dox medium containing 3% sucrose, 0.3% glycine, iprodione at 5 μg ml^-1, azoxystrobin at 1 μg ml^-1, streptomycin at 200 μg ml^-1, and neomycin at 200 μg ml^-1. Colonies of N. psidii on mSGSSM at 30°C for 5 to 10 days were white to orange with sparse aerial hyphae. N. psidii was detected more accurately and efficiently on mSGSSM than on other media, including potato dextrose agar, modified Nash-Snyder medium, and modified Czapek-Dox medium. This semiselective medium is effective in detection of N. psidii from various parts of diseased guava trees and in soil; therefore, it would be a useful medium for etiological, ecological, and epidemiological studies of guava wilt.

Diabetes diminishes the portal-systemic collateral vascular response to vasopressin via vasopressin receptor and Gα proteins regulations in cirrhotic rats

Liver cirrhosis may lead to portal-systemic collateral formation and bleeding. The hemostatic effect is influenced by the response of collateral vessels to vasoconstrictors. Diabetes and glucose also influence vasoresponsiveness, but their net effect on collaterals remains unexplored. This study investigated the impact of diabetes or glucose application on portal-systemic collateral vasoresponsiveness to arginine vasopressin (AVP) in cirrhosis. Spraque-Dawley rats with bile duct ligation (BDL)-induced cirrhosis received vehicle (citrate buffer) or streptozotocin (diabetic, BDL/STZ). The in situ collateral perfusion was done after hemodynamic measurements: Both were perfused with Krebs solution, D-glucose, or D-glucose and NaF, with additional OPC-31260 for the BDL/STZ group. Splenorenal shunt vasopressin receptors and Gα proteins mRNA expressions were evaluated. The survival rate of cirrhotic rats was decreased by STZ injection. The collateral perfusion pressure changes to AVP were lower in STZ-injected groups, which were reversed by OPC-31260 (a V2R antagonist) and overcome by NaF (a G protein activator). The splenorenal shunt V2R mRNA expression was increased while Gα proteins mRNA expressions were decreased in BDL/STZ rats compared to BDL rats. The Gαq and Gα11 mRNA expressions also correlated with the maximal perfusion pressure changes to AVP. Diabetes diminished the portal-systemic collateral vascular response to AVP in rats with BDL-induced cirrhosis, probably via V2 receptor up-regulation and Gα proteins down-regulation.

Enhancement of renal epithelial cell functions through microfluidic-based coculture with adipose-derived stem cells

Current hemodialysis has functional limitations and is insufficient for renal transplantation. The bioartificial tubule device has been developed to contribute to metabolic functions by implanting renal epithelial cells into hollow tubes and showed a higher survival rate in acute kidney injury patients. In healthy kidney, epithelial cells are surrounded by various types of cells that interact with extracellular matrices, which are primarily composed of laminin and collagen. The current study developed a microfluidic coculture platform to enhance epithelial cell function in bioartificial microenvironments with multiple microfluidic channels that are microfabricated by polydimethylsiloxane. Collagen gel (CG) encapsulated with adipose-derived stem cells (CG-ASC) was injected into a central microfluidic channel for three-dimensional (3D) culture. The resuspended Madin-Darby canine kidney (MDCK) cells were injected into nascent channels and formed an epithelial monolayer. In comparison to coculture different cells using the commercial transwell system, the current coculture device allowed living cell monitoring of both the MDCK epithelial monolayer and CG-ASC in a 3D microenvironment. By coculture with CG-ASC, the cell height was increased with columnar shapes in MDCK. Promotion of cilia formation and functional expression of the ion transport protein in MDCK were also observed in the cocultured microfluidic device. When applying fluid flow, the intracellular protein dynamics can be monitored in the current platform by using the time-lapse confocal microscopy and transfection of GFP-tubulin plasmid in MDCK. Thus, this microfluidic coculture device provides the renal epithelial cells with both morphological and functional improvements that may avail to develop bioartificial renal chips.

Effects of simvastatin on the portal-systemic collateral vascular response to endothelin-1 and shunting degree in portal hypertensive rats

OBJECTIVE

Endothelin-1 (ET-1) exerts vasoconstrictive effect on portal-systemic collateral vascular bed of portal hypertensive rats. Statins are lipid-lowering agents with nitric oxide (NO)-related vasodilatory effects. Considering NO-associated vascular hyporesponsiveness to vasoconstrictors and shunting formation in portal hypertension, this study investigated the effects of simvastatin on 1) the portal-systemic collateral vascular responsiveness to ET-1 and 2) the portal-systemic shunting degree.

MATERIALS/METHODS

Portal hypertension was induced by partial portal vein ligation (PVL) in Sprague-Dawley rats. Simvastatin (20 mg/kg/day) or distilled water (control) was randomly administered by oral gavage since 2 days prior to until 7 days after PVL. Systemic and portal hemodynamics were measured on the 8th day. In another series, collateral perfusion with Krebs solution at different flow rates was performed to get flow-pressure curves which serve as an index of shunting degree. To survey the direct vascular effect, PVL rats randomly underwent preincubation with 1) Krebs solution, that is, the control group; or Krebs solution plus 2) simvastatin; 3) simvastatin + N (ω)-nitro-L-arginine (NNA, a NO synthase inhibitor); 4) simvastatin + indomethacin (a cyclooxygenase inhibitor), followed by ET-1 to evaluate the collateral vascular responsiveness.

RESULTS

Chronic simvastatin treatment significantly reduced portal pressure. The flow-pressure curves were similar between two groups. Simvastatin preincubation reduced collateral perfusion pressure changes to ET-1 (p < 0.05), which were partially reversed by NNA (p < 0.05), but not by indomethacin. Conclusions. Chronic simvastatin treatment significantly improved portal hypertension. The effect was at least partially exerted by decreased portal-systemic collateral vascular resistance through NO-mediated vascular hyporesponsiveness. The severity of portal-systemic collaterals was not influenced by simvastatin.

The diminished expression of proangiogenic growth factors and their receptors in gastric ulcers of cirrhotic patients

Objectives

The pathogenesis of the higher occurrence of peptic ulcer disease in cirrhotic patients is complex. Platelets can stimulate angiogenesis and promote gastric ulcer healing. We compared the expressions of proangiogenic growth factors and their receptors in the gastric ulcer margin between cirrhotic patients with thrombocytopenia and those of non-cirrhotic patients to elucidate possible mechanisms.

Methods

Eligible cirrhotic patients (n = 55) and non-cirrhotic patients (n = 55) who had gastric ulcers were enrolled. Mucosa from the gastric ulcer margin and non-ulcer areas were sampled and the mRNA expressions of the proangiogenic growth factors (vascular endothelial growth factor [VEGF], platelet derived growth factor [PDGF], basic fibroblast growth factor [bFGF]) and their receptors (VEGFR1, VEGFR2, PDGFRA, PDGFRB, FGFR1, FGFR2) were measured and compared. Platelet count and the expressions of these growth factors and their receptors were correlated with each other.

Results

The two groups were comparable in terms of gender, ulcer size and infection rate of Helicobacter pylori. However, the cirrhotic group were younger in age, had a lower platelet count than those in the non-cirrhotic group (p<0.05). The cirrhotic patients had diminished mRNA expressions of PDGFB, VEGFR2, FGFR1, and FGFR2 in gastric ulcer margin when compared with those of the non-cirrhotic patients (p<0.05). Diminished expressions of PDGFB and VEGFR2, FGFR1, and FGFR2 were well correlated with the degree of thrombocytopenia in these cirrhotic patients (ρ>0.5, p<0.001).

Conclusions

Our findings implied that diminished activity of proangiogenic factors and their receptors may contribute to the pathogenesis of gastric ulcers in cirrhotic patients.

Usefulness of magnetocardiography to detect coronary artery disease and cardiac allograft vasculopathy

BACKGROUND

Electrophysiological information as well as anatomic information are important for the detection of coronary artery lesions. The aim of this study was to assess the efficacy of resting magnetocardiography (MCG) in stable coronary artery disease (CAD) and cardiac allograft vasculopathy (CAV).

METHODS AND RESULTS

MCG and coronary angiography were performed within 1 month in 75 patients with suspected CAD and in 26 subjects after orthotopic heart transplantation (OHT). Plaque volumes were additionally measured on intravascular ultrasound in OHT recipients. The spatially distributed QT(c) interval maps were constructed with 64-channel MCG. A T-wave propagation map and QT(c) heterogeneity index including QT(c) dispersion and smoothness index of QT(c) (SI-QT(c)) were derived for ischemia detection and localization. CAD patients had higher QT(c) dispersion and SI-QT(c). Receiver operating characteristic curve analysis identified SI-QT(c) ≥9 ms, QT(c) dispersion ≥79 ms as the optimal cut-off for detecting CAD (diagnostic accuracy, 0.7953, 0.7819), better than T-wave propagation (0.6594, P<0.05). There was no significant difference of QT(c) dispersion between CAD and OHT subjects. In OHT recipients, QT(c) dispersion positively correlated with plaque volume, and SI-QT(c) progressively increased after transplantation. Using T-wave propagation mapping, regionally increased dispersion could be demonstrated in CAD patients, but increased dispersion was noted in fewer OHT recipients.

CONCLUSIONS

MCG is clinically feasible as a non-invasive tool for diagnosis of CAD, and could be used as a surrogate marker of CAV.

The association between social relationships and self-harm: a case-control study in Taiwan

BACKGROUND

Although suicide has been postulated as a result of social breakdown, relatively little attention has been paid to the association between social relationships and non-fatal self-harm. We sought to investigate the extent to which social factors correlate with self-harm in this case-control study.

METHODS

The primary outcome was self-harm with hospital presentation. Cases of self-harm from the Emergency Department in a general hospital in Northern Taiwan were recruited, and individually age-and-gender-matched control participants were recruited from non-psychiatric outpatient clinics at the same hospital. The Close Persons Questionnaire was administered and its social support and social network subscales were used to measure social relationships in the 12 months prior to the interview. Other covariates, comprising sociodemographic factors, major life events, physical and mental health, were adjusted in conditional logistic regression models.

RESULTS

A total of 124 case-control pairs were recruited. The mean (standard deviation) age of the case group was 34.7 (12.8) years and 80.6% were female. Higher social isolation score remained significantly associated with self-harm after adjustment (adjusted odds ratio per standard deviation increase 2.92, 95% confidence interval 1.44-5.95) and household size was negatively associated with the outcome (adjusted odds ratio per unit increase 0.54, 95% CI 0.32-0.94).

CONCLUSIONS

More limited social networks were associated with self-harm after adjustment for potential confounders. Enhancing social structure and effective networking of people with self-harm to community resources may be important for self-harm management in Asian societies and elsewhere.

Management of ascites in patients with liver cirrhosis: recent evidence and controversies

Ascites formation in patients with cirrhosis, portal hypertension, or both usually results from hyperdynamic circulatory dysfunction, where the retention of sodium and water is associated with the activation of the sympathetic and renin-angiotensin-aldosterone systems. The presence of ascites indicates the development of liver decompensation. Furthermore, complications seen in conjunction with ascites such as spontaneous bacterial peritonitis, hepatorenal syndrome, and hepatic hydrothorax may result in increased morbidity and mortality. Although nonpharmacological, pharmacological, and surgical approaches have been introduced and clinically practiced, their therapeutic effects are still suboptimal or limited by their potential side effects, such as large-volume paracentesis-induced postparacentesis circulatory dysfunction. Herein, we discuss strategies to prevent and properly manage ascites-related complications, including a review of the literature and controlled studies that assess these strategies.

Chronological changes in renal vascular reactivity in portal hypertensive rats

BACKGROUND

Circulatory dysfunction in portal hypertension is characterized by increased cardiac output, decreased systemic vascular resistance, a fall in mean arterial pressure secondary to splanchnic and systemic vasodilation and hence renal hypoperfusion. Previous studies have disclosed that renal vasculatures of portal hypertensive rats had lower perfusion pressure and hyporesponsiveness to endogenous vasoconstrictors. However, the sequences of altered renal haemodynamics have never been described. This study aimed to explore the evolution of renal vascular hyporeactivity and associated mechanisms during portal hypertension.

MATERIALS AND METHODS

All rats were randomized into partial portal vein ligation (PVL) or shamed surgery. Isolated kidney perfusion was performed at postoperative day 1, 4, 7 and 14, respectively, to evaluate chronologically renal vascular response to endothelin-1. Renal arteries and kidneys were harvested for further analysis.

RESULTS

Impaired renal vascular reactivity to endothelin-1 developed 1 week following PVL. There were extensive up-regulations of vasodilative nitric oxide synthase (NOS) and cyclooxygenase-2 in renal arteries of PVL rats. Among them, the changes in endothelial NOS paralleled with the evolution of renal vascular hyporesponsiveness. Preincubation of NOS inhibitor attenuated the renal vascular hyporeactivity in PVL rats. Up-regulated NOS and down-regulated cyclooxygenase-2 in kidneys of PVL rats might play a critical role to maintain renal circulation and body fluid homoeostasis in response to systemic hypotension.

CONCLUSIONS

This investigation highlights the versatile nature of renal vasculatures in portal hypertension, which is replete with compensatory mechanisms. It may help to unveil potential mechanisms of severe renal dysfunction in advanced liver disease.

IL28B polymorphism correlates with active hepatitis in patients with HBeAg-negative chronic hepatitis B

BACKGROUND AIMS

The clinical relevance of single nucleotide polymorphisms (SNPs) near the IL28B gene is controversial in patients with hepatitis B virus (HBV) infection. This study aimed to investigate the role of viral and host factors, including IL28B genotypes, in the natural course of chronic hepatitis B (CHB).

METHODS

The study enrolled consecutive 115 treatment-naive CHB patients. HBV viral loads, genotypes, precore and basal core promotor mutations, serum hepatitis B surface antigen (HBsAg) and interferon-gamma inducible protein 10 (IP-10) levels as well as four SNPs of IL28B were determined. Serial alanine transaminase (ALT) levels in the previous one year before enrollment at an interval of three months were recorded. Factors associated with active hepatitis, defined as persistent ALT >2× upper limit of normal (ULN) or a peak ALT level >5× ULN, were evaluated.

RESULTS

The prevalence of rs8105790 TT, rs12979860 CC, rs8099917 TT, and rs10853728 CC genotypes were 88.3%, 87.4%, 88.4% and 70.9%, respectively. In HBeAg-positive patients (n = 48), HBV viral load correlated with active hepatitis, while in HBeAg-negative patients (n = 67), rs10853728 CC genotype (p = 0.032) and a trend of higher IP-10 levels (p = 0.092) were associated with active hepatitis. In multivariate analysis, high viral load (HBV DNA >10(8) IU/mL, p = 0.042, odds ratio = 3.946) was significantly associated with HBeAg-positive hepatitis, whereas rs10853728 CC genotype (p = 0.019, odds ratio = 3.927) was the only independent factor associated with active hepatitis in HBeAg-negative population.

CONCLUSIONS

HBV viral load and IL28B rs10853728 CC genotype correlated with hepatitis activity in HBeAg-positive and HBeAg-negative CHB, respectively. Both viral and host factors play roles in disease activity during different phases of CHB.

Assessment of changes in confidence, attitude, and knowledge of non-psychiatric physicians undergoing a depression training program in Taiwan

OBJECTIVE

To assess whether non-psychiatric physicians would benefit from a national depression training program and explore associated factors.

METHOD

Attending physicians were asked to complete survey questionnaires of confidence, attitude, knowledge, and their willingness to implement new strategies to improve care, before and after training. Paired t-test and multiple regression analysis were used to determine the differences and explore factors associated with the domains of confidence, attitude, and knowledge. McNemar's test was used to compare the difference between the physicians' intention to change depression management before and after training.

RESULTS

Of 524 eligible physicians, 307 (59%) completed the pre- and post-program assessments. These physicians showed significantly increased knowledge score and willingness to implement new treatment strategies, as well as more positive attitude toward and confidence in treating depression. The lower corresponding baseline score was associated with greater improvement in domains ofknowledge, confidence, and attitude. Completion of the training was associated with an improvement in knowledge and becoming less helpless and avoidant attitude. Other factors including non-family-medicine physicians, post-graduate education, and female gender are associated with greater improvements in various domains.

CONCLUSIONS

Our study shows that even a brief educational program can positively influence the physicians' knowledge, attitudes, and confidence in treating depression. Further work is needed to monitor whether the effects of training are long-term, and can be translated into behavioral change in practice.

The influence of sorafenib on hepatic encephalopathy and the mechanistic survey in cirrhotic rats

BACKGROUND

Sorafenib, a multikinase inhibitor that inhibits angiogenesis and carcinogenesis, has been used for patients with advanced hepatocellular carcinoma. However, sporadic cases have been reported with the development of hepatic encephalopathy (HE) after sorafenib treatment, mostly in those with cirrhosis. Liver function impairment, portal-systemic collaterals and brain oxidative stress participate in the pathogenesis of HE. The study therefore aimed to investigate the potential influences of sorafenib on HE and the relevant risk factors in cirrhotic rats.

METHODS

Liver cirrhosis was induced in Spraque-Dawley rats with common bile duct ligation (CBDL). CBDL rats received sorafenib 1 mg/kg/day or distilled water (DW) via oral gavage since the 15th day post surgery for 2 weeks. On the 28th day, after motor activities measurements, mean arterial pressure, portal pressure and heart rate were checked. Thereafter, cerebral cortex and cerebellum were dissected for oxidative stress study and blood was collected for liver biochemistry survey.

RESULTS

Sorafenib significantly reduced portal pressure (22%) and collateral shunting degree (15%) in cirrhotic rats. Alanine transaminase, aspartate transaminase, total bilirubin and ammonia were similar in sorafenib- and DW-treated groups. Motor activities were not significantly altered by sorafenib. In cerebrum, the oxidant and antioxidant substances activities were not significantly different between the two groups, whereas they were divergent in cerebellum and hippocampus.

CONCLUSION

By surveying three main aspects involved in the pathogenesis of HE, this study demonstrates that sorafenib does not increase the risk of HE in cirrhotic rats.

Intestinal and plasma VEGF levels in cirrhosis: the role of portal pressure

Increased levels of intestinal VEGF are thought to worsen portal hypertension. The cause of the increase in the level of intestinal VEGF found during cirrhosis is not known. The aim of this study is to demonstrate a relationship between portal pressure (PP) and intestinal/ plasma VEGF levels in different stages of fibrosis/cirrhosis. In this experiment, rats were exposed to carbon tetrachloride (CCl₄) for 6, 8 and 12 weeks. At the end of exposure, the three groups of rats exhibited three different stages of pathology: non-cirrhotic, early fibrotic and cirrhotic, respectively. For those rats and their age-matched controls, PP and intestinal/plasma VEGF levels were measured. Rats inhaling CCl₄ for 12 weeks developed portal hypertension (18.02 ± 1.07 mmHg), while those exposed for 6 weeks (7.26 ± 0.58 mmHg) and for 8 weeks (8.55 ± 0.53 mmHg) did not. The rats exposed for 12 weeks also showed a 40% increase in the level of intestinal VEGF compared to the controls (P < 0.05), while those rats exposed to CCl₄ inhalation for 6 and 8 weeks did not. There was a significant positive correlation between PP and intestinal VEGF levels (r² = 0.4, P < 0.005). Plasma VEGF levels were significantly elevated in those rats exposed to 12 weeks of CCl₄ inhalation (63.7 pg/ml, P < 0.01), compared to the controls (8.5 pg/ml). However, no correlation was observed between PP and plasma VEGF levels. It is concluded that portal pressure modulates intestinal VEGF levels during the development of cirrhosis.

Cannabinoid receptor 2 agonist ameliorates mesenteric angiogenesis and portosystemic collaterals in cirrhotic rats

Angiogenesis in liver cirrhosis leads to splanchnic hyperemia, increased portal inflow, and portosystemic collaterals formation, which may induce lethal complications, such as gastroesophageal variceal hemorrhage and hepatic encephalopathy. Cannabinoids (CBs) inhibit angiogenesis, but the relevant influences in cirrhosis are unknown. In this study, Spraque-Dawley rats received common bile duct ligation (BDL) to induce cirrhosis. BDL rats received vehicle, arachidonyl-2-chloroethylamide (cannabinoid receptor type 1 [CB(1) ] agonist), JWH-015 (cannabinoid receptor type 2 [CB(2) ] agonist), and AM630 (CB(2) antagonist) from days 35 to 42 days after BDL. On the 43rd day, hemodynamics, presence of CB receptors, severity of portosystemic shunting, mesenteric vascular density, vascular endothelial growth factor (VEGF), VEGFR-1, VEGFR-2, phospho-VEGFR-2, cyclooxygenase (COX)-1, COX-2, and endothelial nitric oxide synthase (eNOS) expressions as well as plasma VEGF levels were evaluated. Results showed that CB(1) and CB(2) receptors were present in left adrenal veins of sham rats, splenorenal shunts (the most prominent intra-abdominal shunts) of BDL rats, and mesentery of sham and BDL rats. CB(2) receptor was up-regulated in splenorenal shunts of BDL rats. Both acute and chronic JWH-015 treatment reduced portal pressure and superior mesenteric arterial blood flow. Compared with vehicle, JWH-015 significantly alleviated portosystemic shunting and mesenteric vascular density in BDL rats, but not in sham rats. The concomitant use of JWH-015 and AM630 abolished JWH-015 effects. JWH-133, another CB(2) agonist, mimicked the JWH-015 effects. JWH-015 decreased mesenteric COX-1, COX-2 messenger RNA expressions, and COX-1, COX-2, eNOS protein expressions. Furthermore, JWH-015 decreased intrahepatic angiogenesis and fibrosis.

CONCLUSIONS

CB(2) agonist alleviates portal hypertension (PH), severity of portosystemic collaterals and mesenteric angiogenesis, intrahepatic angiogenesis, and fibrosis in cirrhotic rats. The mechanism is, at least partly, through COX and NOS down-regulation. CBs may be targeted in the control of PH and portosystemic collaterals.