[Visual impact of sub-tenon's anesthesia during surgery for retinal detachment]

Objective: To investigate the visual impact and influence factors of sub-Tenon's anesthesia in retinal detachment patients during pars plana vitrectomy (PPV) or combined phacoemulsification and PPV surgery. Methods: In this prospective case series study, 104 consecutive patients who underwent PPV or combined phacoemulsification and PPV under sub-Tenon's anesthesia between October 2012 and December 2013 were enrolled. Intraoperatively, the patients were asked whether they could see the light of the operating microscope or not at 5 minutes after sub-Tenon's anesthesia, and at the end of phacoemulsification, core vitreous removal, peripheral vitreous removal and the whole surgery, with their contralateral eyes being covered tightly and no photobleaching. The best corrected visual acuity and visual evoked potentials were examined and compared with each other preoperatively and at 1.5 months and 3 months postoperatively. Chi-square test was used to compare the detection rate of amaurosis between different modus operandi and whether covered contra-lateral eye. Student-t test was used to compare the difference of age and preoperative BCVA between the patients with or without experienced amaurois. Lastly, BCVA between different times were tested by one-way ANOVA analysis. Results: Without covering the contralateral eyes, the incidence of no light perception in various surgical steps was 0%, while it was 72.1%(75/104), 93.8%(75/80), 96.2%(100/104), 96.2%(100/104) and 86.5%(90/104) at the five timepoints, respectively, when the contralateral eyes were covered tightly. The incidence was 51.9%(54/104), 85.0%(68/80), 85. 6%(89/104), 84.6%(69/104) and 66.3%(88/104), respectively, after photobleaching was excluded. Approximately 95.2%(99/104) of patients reported no light perception at least once, 54.5%(54/99) reported no light perception 5 minutes after sub-Tenon's anesthesia, and 30.3%(30/99) recovered light perception when the surgery was finished. All eyes recovered to at least light perception on the first postoperative day. The best corrected visual acuity and visual evoked potentials at 1.5 months and 3 months postoperatively were significantly better than those before surgery. The BCVA was 1.75±0.78 preoperative, 0.96±0.63 1.5 months after operation, and 0.92±0.57 3 months after operation. There was a significant statistical difference between preoperative BCVA and postoperative BCVA (F=50.61, P<0.01) . In patients without waveform detection preoperatively, PVEP waveform could be found in 43.6% and 61.4% of the pactients at 1.5 months and 3 months after operation respectively. In those had certain waveform preoperatively, PVEP amplitudes rise significantly after surgery (t(1.5)=-2.69, t(3)=-2.97, P<0.05) . Conclusions: No light perception was detected in various surgical steps of vitrectomy under sub-Tenon's anesthesia in most patients. The blocking of optic nerve conduction may be caused by sub-Tenon' s anesthesia. Photobleaching can also have some effect. The incidence of no light perception during the surgery was not correlated with preoperative visual acuity, age and gender. Moreover, the effect was transient and harmless to visual function.(Chin J Ophthalmol, 2017, 53: 332-337).

Surface Engineering of Polycrystalline Silicon for Long-Term Mechanical Stress Endurance Enhancement in Flexible Low-Temperature Poly-Si Thin-Film Transistors

The surface morphology in polycrystalline silicon (poly-Si) film is an issue regardless of whether conventional excimer laser annealing (ELA) or the newer metal-induced lateral crystallization (MILC) process is used. This paper investigates the stress distribution while undergoing long-term mechanical stress and the influence of stress on electrical characteristics. Our simulated results show that the nonuniform stress in the gate insulator is more pronounced near the polysilicon/gate insulator edge and at the two sides of the polysilicon protrusion. This stress results in defects in the gate insulator and leads to a nonuniform degradation phenomenon, which affects both the performance and the reliability in thin-film transistors (TFTs). The degree of degradation is similar regardless of bending axis (channel-length axis, channel-width axis) or bending type (compression, tension), which means that the degradation is dominated by the protrusion effects. Furthermore, by utilizing long-term electrical bias stresses after undergoing long-tern bending stress, it is apparent that the carrier injection is severe in the subchannel region, which confirms that the influence of protrusions is crucial. To eliminate the influence of surface morphology in poly-Si, three kinds of laser energy density were used during crystallization to control the protrusion height. The device with the lowest protrusions demonstrates the smallest degradation after undergoing long-term bending.

Effects of raloxifene on portal hypertension and hepatic encephalopathy in cirrhotic rats

Raloxifene, a selective estrogen receptor modulator, has been used extensively for osteoporosis. In addition to the effect of osteoporosis treatment, emerging evidences show that raloxifene affects the vascular function in different tissues. Cirrhosis is characterized with portal hypertension and complicated with hepatic encephalopathy. Portal hypertension affects portal-systemic shunt which leads to hepatic encephalopathy that the vascular modulation might influence severity of hepatic encephalopathy. Herein, we evaluated the impact of raloxifene on bile duct ligation (BDL)-induced cirrhotic rats. The female Sprague-Dawley rats received BDL plus ovariectomy or sham-operation. Four weeks later, rats were divided into 2 subgroups respectively to receive of raloxifene (10mg/kg/day) or saline (vehicle) for 14 days. On the 43th day, motor activities and hemodynamic parameters were measured. Hepatic and vascular mRNA and protein expressions were determined. The histopathological change of liver was examined. We found that the liver biochemistry, ammonia level and motor activity were similar between cirrhotic rats with or without raloxifene administration. The hemodynamic parameters were not significantly different except that raloxifene reduced portal venous inflow. Raloxifene exacerbated hepatic fibrosis and up-regulated hepatic endothelin-1 and cyclooxygenase 2 protein expressions. In addition, raloxifene modulated the mRNA expressions of endothelial nitric oxide synthase, cyclooxygenase and endothelin-1 in the superior mesenteric artery and collateral vessel. In conclusion, raloxifene aggravates hepatic fibrosis and decreases portal venous inflow in cirrhotic rats without adversely affecting portal hypertension and hepatic encephalopathy. The modulation of hepatic and vascular endothelin-1, endothelial nitric oxide synthase and cyclooxygenase expressions may play a role in the mechanism.

Resistance Switching Characteristics Induced by O2 Plasma Treatment of an Indium Tin Oxide Film for Use as an Insulator in Resistive Random Access Memory

In this study, an O₂ inductively coupled plasma (ICP) treatment was developed in order to modify the characteristics of indium tin oxide (ITO) film for use as an insulator in resistive random access memory (RRAM). After the O₂ plasma treatment, the previously conductive ITO film is oxidized and becomes less conductive. In addition, after capping the same ITO material for use as a top electrode, we found that the ITO/ITO(O₂ plasma)/TiN device exhibits very stable and robust resistive switching characteristics. On the contrary, the nontreated ITO film for use as an insulator in the ITO/ITO/TiN device cannot perform resistance switching behaviors. The material analysis initially investigated the ITO film characteristics with and without O₂ plasma treatment. The surface was less rough after O₂ plasma treatment. However, the molar concentration of each element and measured sheet resistance results for the O₂-plasma-treated ITO film were dramatically modified. Next, electrical measurements were carried out to examine the resistance switching stability under continuous DC and AC operation in this ITO/ITO(O₂ plasma)/TiN device. Reliability tests, including endurance and retention, also proved its capability for use in data storage applications. In addition to these electrical measurements, current fitting method experiments at different temperatures were performed to examine and confirm the resistance switching mechanisms. This easily fabricated device, using a simple material combination, achieves excellent performance by using ITO with an O₂ plasma treatment and can further the abilities of RRAM for use in remarkable potential applications.

Homocysteine deteriorates intrahepatic derangement and portal-systemic collaterals in cirrhotic rats

In liver cirrhosis, the altered levels of vasoactive substances, especially endothelin-1 (ET-1) and nitric oxide (NO) lead to elevated intrahepatic resistance, increased portal-systemic collaterals and abnormal intra- and extra-hepatic vascular responsiveness. These derangements aggravate portal hypertension-related complications such as gastro-oesophageal variceal bleeding. Homocysteine, a substance implicated in cardiovascular diseases, has been found with influences on vasoresponsiveness and angiogenesis. However, their relevant effects in liver cirrhosis have not been investigated. In the present study, liver cirrhosis was induced by common bile duct ligation (BDL) in Sprague–Dawley rats. In acute study, the results showed that homocysteine enhanced hepatic vasoconstriction to ET-1 but decreased portal-systemic collateral vasocontractility to arginine vasopressin (AVP). Homocysteine down-regulated hepatic phosphorylated endothelial NO synthase (p-eNOS) and p-Akt protein expressions. Inducible NOS (iNOS) and cyclooxygenase (COX)-2 expressions were up-regulated by homocysteine in splenorenal shunt (SRS), the most prominent intra-abdominal collateral vessel. In chronic study, BDL or thioacetamide (TAA) rats received homocysteine or vehicle for 14 days. The results revealed that homocysteine increased hepatic collagen fibre deposition and fibrotic factors expressions in both BDL- and TAA-induced liver fibrotic rats. Portal-systemic shunting and expressions of mesenteric angiogenetic factors [vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF), PDGF receptor β (PDGFRβ) and p-eNOS] were also increased in BDL rats. In conclusion, homocysteine is harmful to vascular derangements and liver fibrosis in cirrhosis.

An Open-Label, Randomized Trial of Methylphenidate and Atomoxetine Treatment in Adults With ADHD

OBJECTIVE

To directly compare the efficacy of methylphenidate and atomoxetine in improving symptoms, social functions, and quality of life among adults with ADHD.

METHOD

This was an 8-to-10-week, open-label, head-to-head, randomized clinical trial with two treatment arms: immediate-release methylphenidate (IR-methylphenidate; n = 31) and atomoxetine once daily ( n = 32). The outcome measures included ADHD symptom severity, quality of life, and functional impairments.

RESULTS

We found a significant reduction in overall ADHD symptoms and improvement in social functions and quality of life for both groups at Weeks 4 to 5 and Weeks 8 to 10. There was no significant difference in the slope of improvements over time except that atomoxetine was superior to IR-methylphenidate in reducing hyperactive/impulsive symptoms at Weeks 4 to 5. There was no significant group difference in the rates of adverse effects.

CONCLUSION

Both IR-methylphenidate and atomoxetine are well tolerated and efficacious in ethnic Chinese adults with ADHD.

Effects of the traditional Chinese herb Astragalus membranaceus in patients with poststroke fatigue: A double-blind, randomized, controlled preliminary study

BACKGROUND AND PURPOSE

Astragalus membranaceus (AM) is the first-choice herb for fatigue treatment in traditional Chinese medicine and the main herb used for stroke treatment in China and Taiwan. The purpose of this study was to evaluate the effect of AM on poststroke fatigue (PSF).

MATERIALS AND METHODS

This study was designed as a double-blind, randomized, controlled preliminary study. Sixty-four patients with PSF were assigned to treatment group (TG; 31 patients), which received oral administration of AM (2.8g three times per day) for 28 days, and a control group (CG; 33 patients), which received a placebo. The primary outcome measures were the changes in the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30) and Brief Fatigue Index (BFI) scores RESULTS: A total of 61 patients (29 patients in the TG and 32 patients in the CG) completed the trial. The difference in BFI scores between Visit 2 and Visit 1 was -17.83±17.70 in the TG, which was greater than that in the CG (-8.03±9.95; p=0.01); additionally, the difference in BFI scores between Visit 3 and Visit 1 was -16.48±16.41 in the TG, which was also greater than that in the CG (-9.47±13.39; p=0.05). In the EORTC QLQ-C30, the difference in cognitive functioning scores between Visit 2 and Visit 1 was 14.37±13.89 in the TG, which was greater than that in the CG (3.65±19.74; p=0.02); additionally, the difference in these scores between Visit 3 and Visit 1 was 14.37±16.50 in the TG, which again was greater than that in the CG (6.25±19.74; p=0.04). The difference in social functioning scores between Visit 3 and Visit 1 was 9.77±15.12 in the TG, which was greater than that in the CG (-1.56±20.46; p=0.01). The difference in global quality of life (QOL) scores between Visit 2 and Visit 1 was 14.08±18.78 in the TG, which was also greater than that in the CG (1.56±18.14; p=0.003); moreover, the difference in these scores between Visit 3 and Visit 1 was 10.92±17.55 in the TG, and this was greater than that in the CG (1.82±15.8; p=0.05).

CONCLUSION

AM can improve BFI scores; cognitive functioning, social functioning, and global QOL scores in the EORTC QLQ-C30. Our results suggest that physicians should pay close attention to the unmet medical needs of patients with PSF. AM is helpful for treating patients with PSF; however, additional studies with a larger sample and a longer period of investigation are required.

Role of cyclooxygenase isoforms in encephalopathy of cirrhotic rats

BACKGROUND

Hepatic encephalopathy (HE) is a complex neuropsychiatric syndrome secondary to acute or chronic liver failure. However, its pathophysiology remains obscure. Recently, we found that the inhibition of cyclooxygenase by indomethacin aggravated HE in rats with thioacetamide-induced acute hepatic failure, suggesting a pivotal role of cyclooxygenase in HE. This study was aimed at surveying the roles of cyclooxygenase isoforms responsible for prostaglandins synthesis, cyclooxygenase-1 (COX1) and COX2, in cirrhotic rats with HE.

METHODS

Liver cirrhosis was induced (using formalin) in male Sprague-Dawley rats with bile duct ligation (FBDL). Sham-operated rats served as the surgical controls. The severity of HE was assessed by motor activity counts. Plasma 6-keto-prostaglandin-F_1α [6-keto-PGF_1α; a relatively stable metabolite of prostacyclin (PGI₂)], alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALK-P), and total bilirubin were measured. Hepatic mRNA expressions of COX1 and COX2 were tested.

RESULTS

The FBDL group showed lower motor activity counts than the sham group in total (1472 ± 156 vs. 2174 ± 262 counts/30 min, p = 0.034), ambulatory (824 ± 99 vs. 1443 ± 206 counts/30 min, p = 0.014), and vertical movement (431 ± 69 vs. 849 ± 145 counts/30 min, p = 0.018). The mRNA expression of hepatic COX2 was significantly higher in the FBDL group. Plasma ALK-P and bilirubin levels were negatively correlated with total movements, respectively (both p < 0.05). In addition, hepatic COX2 mRNA expression was positively correlated with AST, ALK-P, total bilirubin, and 6-keto-PGF_1α (all p < 0.05), but not correlated with total movements.

CONCLUSION

Hepatic COX2 expression and PGI₂ production are enhanced in cirrhotic rats, but the correlation with HE is not remarkable. Cyclooxygenase and PGI₂ may not play important roles in HE in the setting of chronic liver failure.

Endothelin receptor blockers reduce shunting and angiogenesis in cirrhotic rats

BACKGROUND

Angiogenesis plays a pivotal role in splanchnic hyperaemia and portosystemic collateral formation in cirrhosis. Endothelin-1 (ET-1), an endothelium-derived vasoconstrictor, has also been implicated in the pathogenesis of cirrhosis and portal hypertension.

DESIGN

This study aimed to survey the influences of ET-1 in cirrhosis-related angiogenesis. Common bile duct ligation was performed on Spraque-Dawley rats to induce cirrhosis. Since the 14th day after the operation, rats randomly received distilled water (DW, control), bosentan [a nonselective ET receptor (ETR) blocker] or ambrisentan (a selective ETA R blocker) for 4 weeks. On the 43rd day, portal and systemic haemodynamics, liver biochemistry, portosystemic shunting degree, mesenteric vascular density, mRNA and/or protein expressions of relevant angiogenic factors were evaluated.

RESULTS

In cirrhotic rats, bosentan significantly reduced portal pressure. Ambrisentan did not influence haemodynamics and liver biochemistry. Both of them significantly improved the severity of portosystemic collaterals and decreased the mesenteric vascular density. Compared with the DW-treated cirrhotic rats, splenorenal shunt and mesenteric inducible nitric oxide synthase (iNOS), cyclooxygenase 2 (COX2), vascular endothelial growth factor mRNA expressions and mesenteric iNOS, COX2, VEGF, phospho-VEGF receptor 2, Akt and phospho-Akt protein expressions were down-regulated in both groups.

CONCLUSIONS

In rats with liver cirrhosis, both nonselective and selective ETA R blockade ameliorate the severity of portosystemic shunting and mesenteric angiogenesis via the down-regulation of VEGF pathway and relevant angiogenic factors. ET receptors may be targeted to control the severity of portosystemic collaterals and associated complications in cirrhosis.

Resting respiratory sinus arrhythmia is related to longer hospitalization in mood-disordered repetitive suicide attempters

OBJECTIVES

Our aims were (1) to measure respiratory sinus arrhythmia (RSA), a high-frequency spectrum component of heart rate variability (HRV) in mood-disordered suicide attempters and (2) to investigate the relationship of RSA to symptoms and length of hospitalization.

METHODS

Forty-nine female repetitive-suicide attempters with depressive disorder or bipolar disorder were recruited in a general hospital setting. Manic or psychotic patients were excluded. Resting RSA values were calculated from electrocardiogram data, and severity of clinical presentation shortly after admission and length of hospital stay were assessed.

RESULTS

RSA was positively associated with a higher Beck Scale for Suicidal Ideation score (r = 0.33 P = 0.019). Stepwise multiple regression analysis showed a significant correlation between RSA and hospitalization length after adjusting other variables (beta coefficient = 3.00; P = 0.030). Patients with a higher resting RSA had more prolonged hospitalizations (hospitalization beyond 30 days) after controlling for other variables (odds ratio = 5.08, P = 0.017).

CONCLUSIONS

Interaction between the environment and the autonomic nervous system is complex. Further and more comprehensive research is needed.

2'-Hydroxyflavanone ameliorates mesenteric angiogenesis and portal-systemic collaterals in rats with liver fibrosis

BACKGROUND AND AIM

Portal-systemic collaterals lead to dreadful consequences in patients with cirrhosis. Angiogenesis participates in the development of liver fibrosis, hyperdynamic circulation, and portal-systemic collaterals. 2'-Hydroxyflavanone (2'-HF), one of the citrus fruits flavonoids, is known to have antiangiogenesis effect without adverse response. However, the relevant effects in liver fibrosis have not been surveyed.

METHODS

Male Wistar rats received thioacetamide (TAA, 100 mg/kg tiw, i.p.) for 6 weeks to induce liver fibrosis. On the 29th to 42nd day, rats randomly received 2'-HF (100 mg/kg, qod, i.p.) or vehicle (corn oil). On the 43rd day, after hemodynamic measurements, the followings were surveyed: (i) severity of collaterals; (ii) mesenteric angiogenesis; (iii) mesenteric proangiogenic factors protein expressions; (iv) Mesenteric vascular endothelial cells apoptosis; and (v) Mesenteric expressions of proteins regulating apoptosis.

RESULTS

Compared with the vehicle group, 2'-HF did not significantly change body weight, mean arterial pressure, heart rate, and portal pressure in TAA rats. 2'-HF significantly alleviated the severity of collaterals, but the mesenteric phospho-ERK, ERK, phospho-Akt, Akt, COX1, COX2, VEGF, and VEGFR-2 protein expressions were not altered. The apoptotic index of 2'-HF group was significantly higher and the mesenteric protein expressions of pro-apoptotic factors, NFkB 50, NFkB 65, Bax, phospho-p53, 17 kD cleaved caspase 3, and 17 kD casepase 3 were up-regulated.

CONCLUSIONS

2'-HF does not influence the hemodynamics but alleviated the severity of collaterals in rats with liver fibrosis and early portal hypertension. This is, at least partly, attributed to enhanced apoptosis of mesenteric vascular endothelial cells.

Self-harm and its association with internet addiction and internet exposure to suicidal thought in adolescents

BACKGROUND/PURPOSE

Self-harm (SH) is a risk factor for suicide. We aimed to determine whether internet addiction and internet exposure to confided suicidal ideation are associated with SH in adolescents.

METHODS

This study was a cross-sectional survey of students who self-completed a series of online questionnaires including a sociodemographic information questionnaire, questionnaire for suicidality and SH, Chen Internet Addiction Scale (CIAS), Patient Health Questionnaire (PHQ-9), multi-dimensional support scale (MDSS), Rosenberg self-esteem scale (RSES), Alcohol Use Disorder Identification Test-Consumption (AUDIT-C), and questionnaire for substance abuse.

RESULTS

A total of 2479 students completed the questionnaires (response rate = 62.1%). They had a mean age of 15.44 years (range 14-19 years; standard deviation 0.61), and were mostly female (n = 1494; 60.3%). The prevalence of SH within the previous year was 10.1% (n = 250). Among the participants, 17.1% had internet addiction (n = 425) and 3.3% had been exposed to suicidal content on the internet (n = 82). In the hierarchical logistic regression analysis, internet addiction and internet exposure to suicidal thoughts were both significantly related to an increased risk of SH, after controlling for gender, family factors, exposure to suicidal thoughts in the real life, depression, alcohol/tobacco use, concurrent suicidality, and perceived social support. However, the association between internet addiction and SH weakened after adjusting for the level of self-esteem, while internet exposure to suicidal thoughts remained significantly related to an increased risk of SH (odds ratio = 1.96; 95% confidence interval: 1.06-3.64).

CONCLUSION

Online experiences are associated with SH in adolescents. Preventive strategies may include education to increase social awareness, to identify the youths most at risk, and to provide prompt help.

Atomoxetine could improve intra-individual variability in drug-naïve adults with attention-deficit/hyperactivity disorder comparably with methylphenidate: A head-to-head randomized clinical trial

OBJECTIVE

Intra-individual variability in reaction time (IIV-RT) is common in individuals with attention-deficit/hyperactivity disorder (ADHD). It can be improved by stimulants. However, the effects of atomoxetine on IIV-RT are inconclusive. We aimed to investigate the effects of atomoxetine on IIV-RT, and directly compared its efficacy with methylphenidate in adults with ADHD.

METHODS

An 8-10 week, open-label, head-to-head, randomized clinical trial was conducted in 52 drug-naïve adults with ADHD, who were randomly assigned to two treatment groups: immediate-release methylphenidate (n=26) thrice daily (10-20 mg per dose) and atomoxetine once daily (n=26) (0.5-1.2 mg/kg/day). IIV-RT, derived from the Conners' continuous performance test (CCPT), was represented by the Gaussian (reaction time standard error, RTSE) and ex-Gaussian models (sigma and tau). Other neuropsychological functions, including response errors and mean of reaction time, were also measured. Participants received CCPT assessments at baseline and week 8-10 (60.4±6.3 days).

RESULTS

We found comparable improvements in performances of CCPT between the immediate-release methylphenidate- and atomoxetine-treated groups. Both medications significantly improved IIV-RT in terms of reducing tau values with comparable efficacy. In addition, both medications significantly improved inhibitory control by reducing commission errors.

CONCLUSION

Our results provide evidence to support that atomoxetine could improve IIV-RT and inhibitory control, of comparable efficacy with immediate-release methylphenidate, in drug-naïve adults with ADHD. Shared and unique mechanisms underpinning these medication effects on IIV-RT awaits further investigation.

The ability of 17 β-estradiol to attenuate intrahepatic vasoconstriction to endothelin-1 in female rats is lost in cirrhosis

BACKGROUND AND RATIONALE

The control of Endothelin-1 (ET-1)-mediated intrahepatic vasoconstriction in cirrhosis is beneficial for the alleviation of relevant complications. Cirrhosis is accompanied by hypogonadism and altered sex hormone status. Besides, sex hormones have vasoactive effects, but it is unknown if they influence vascular function in cirrhosis. This study aimed to investigate the roles of sex hormones in hepatic vascular reactions to ET-1 in cirrhosis. Liver cirrhosis was induced in Spraque-Dawley male and female rats with common bile duct ligation (BDL). Sham-operated (Sham) rats were controls. On the 43rd day after operations, intrahepatic vascular concentration-response curves to ET-1 were obtained with the following preincubatioins: 1) vehicle; 2) 17ß-estradiol; 3) progesterone; 4) testosterone. Livers from sham and BDL rats were dissected for real-time polymerase chain reaction analysis of estrogen, progesterone and testosterone receptors.

RESULTS

Compared with sham males perfused with vehicle, sham females presented higher perfusion pressure changes to ET-1 which was reversed only by 17 ß-estradiol. In cirrhosis, compared with males, 17 ß-estradiol no longer attenuated vascular responsiveness to ET-1 in females. In females, BDL rats had lower hepatic estrogen receptor α(ERβα) mRNA expression than that in sham rats.

CONCLUSIONS

The sham females showed a stronger intrahepatic vascular constrictive effect to ET-1 than sham males, which could be reversed by 17β-estradiol. However, the influence of 17 β-estradiol was lost in cirrhotic females, which may be attributed, at least partly, to intrahepatic ER α down-regulation in females with cirrhosis.

Clopidogrel inhibits angiogenesis of gastric ulcer healing via downregulation of vascular endothelial growth factor receptor 2

BACKGROUND/PURPOSE

Although clopidogrel does not cause gastric mucosal injury, it does not prevent peptic ulcer recurrence in high-risk patients. We explored whether clopidogrel delays gastric ulcer healing via inhibiting angiogenesis and to elucidate the possible mechanisms.

METHODS

Gastric ulcers were induced in Sprague Dawley rats, and ulcer healing and angiogenesis of ulcer margin were compared between clopidogrel-treated rats and controls. The expressions of the proangiogenic growth factors and their receptors including basic fibroblast growth factor (bFGF), bFGF receptor (FGFR), vascular endothelial growth factor (VEGF), VEGFR1, VEGFR2, platelet-derived growth factor (PDGF)A, PDGFB, PDGFR A, PDGFR B, and phosphorylated form of mitogenic activated protein kinase pathways over the ulcer margin were compared via western blot and reverse transcription polymerase chain reaction. In vitro, human umbilical vein endothelial cells (HUVECs) were used to elucidate how clopidogrel inhibited growth factors-stimulated HUVEC proliferation.

RESULTS

The ulcer sizes were significantly larger and the angiogenesis of ulcer margin was significantly diminished in the clopidogrel (2 and 10 mg/kg/d) treated groups. Ulcer induction markedly increased the expression of phosphorylated form of extracellular signal-regulated kinase (pERK), FGFR2, VEGF, VEGFR2, and PDGFRA when compared with those of normal mucosa. Clopidogrel treatment significantly decreased pERK, FGFR2, VEGF, VEGFR2, and PDGFRA expression at the ulcer margin when compared with those of the respective control group. In vitro, clopidogrel (10(-6)M) inhibited VEGF-stimulated (20 ng/mL) HUVEC proliferation, at least, via downregulation of VEGFR2 and pERK.

CONCLUSION

Clopidogrel inhibits the angiogenesis of gastric ulcer healing at least partially by the inhibition of the VEGF-VEGFR2-ERK signal transduction pathway.

The Impact of Spironolactone on the Severity of Portal-Systemic Collaterals and Hepatic Encephalopathy in Cirrhotic Rats

Liver cirrhosis and portal hypertension are accompanied by portal-systemic collaterals formation and lethal complications. Angiogenesis participates in the development of collaterals. Spironolactone is an aldosterone receptor antagonist used to control fluid overload in cirrhotic patients although recent studies suggest that it also inhibits angiogenesis. This study investigated the effect of spironolactone on abnormal angiogenesis and portal-systemic collaterals in cirrhosis. Liver cirrhosis was induced in Sprague-Dawley rats by common bile duct ligation (BDL), and sham-operated rats were the controls. The BDL and sham rats received spironolactone (20 mg/kg/d, oral gavage) or vehicle from day 15 to 28 after the operations. Spironolactone did not influence the portal and systemic hemodynamic, and the renal and hepatic biochemistry data, but it significantly ameliorated hepatic fibrosis, portal-systemic shunting, and mesenteric angiogenesis. Plasma vascular endothelial growth factor (VEGF) levels and the mesenteric protein expression of VEGF and phosphor-vascular endothelial growth factor receptor 2 (VEGFR-2) decreased in the spironolactone group. Spironolactone did not affect motor activity or plasma ammonia levels. The down-regulation of VEGF pathway participates, albeit partly, in the antiangiogenic effect of spironolactone. Thus, spironolactone treatment in patients with liver cirrhosis may provide additional benefits aside from ascites control.

Durability of Nucleos(t)ide Analogues Treatment in Patients With Chronic Hepatitis B

Long-term nucleos(t)ide analogues (NUCs) treatment is usually required for patients with chronic hepatitis B (CHB). However, whether discontinuation of NUCs is possible in selected patients remains debated. The aim of this study was to assess the durability of NUCs and predictors of sustained response after cessation of NUCs.Ninety-three CHB patients (29 HBeAg-positive and 64 HBeAg-negative) from 2 medical centers in Taiwan with discontinuation of NUCs after a median of 3 years' treatment were retrospectively reviewed. Fifteen (51.7%) HBeAg-positive and 57 (89.1%) HBeAg-negative patients achieved APASL treatment endpoints. Virological relapse (VR) and clinical relapse (CR) were defined according to APASL guidelines.Achieving APASL endpoint was associated with longer median time to CR in HBeAg-positive patients, but not in HBeAg-negative cases. The cumulative 1-year VR and CR rates were 55.3% and 14.4% in HBeAg-positive patients, and 77.7% and 41.9% in HBeAg-negative patients, respectively. In HBeAg-negative patients, baseline HBV DNA >10 IU/mL was the only predictor of VR (hazard ratio [HR] = 2.277, P = 0.019) and CR (HR = 3.378, P = 0.014). HBsAg >200 IU/mL at the end of treatment (EOT) was associated with CR (HR = 3.573, P = 0.023) in patients developing VR. HBeAg-negative patients with low baseline viral loads and low HBsAg levels at EOT had minimal risk of CR after achieving APASL treatment endpoint (P = 0.016).The VR rate is high, but the risk of CR is low within 1 year with consolidation treatment after HBeAg seroconversion. Longer consolidation treatment to reduce the risk of VR should be considered in HBeAg-positive patients. As high risk of VR and CR, cessation of NUCs therapy could be considered only in selected HBeAg-negative patients.

The Beneficial Effects of P2X7 Antagonism in Rats with Bile Duct Ligation-induced Cirrhosis

Splanchnic angiogenesis in liver cirrhosis often leads to complications as gastroesophageal variceal hemorrhage and the treatment efficacy is adversely affected by poor portal-systemic collateral vasoresponsiveness related to nitric oxide (NO). Purinergic receptor subtype P2X7 participates in the modulation of inflammation, angiogenesis, fibrogenesis and vasoresponsiveness, but the relevant influence in cirrhosis is unknown. Common bile duct-ligated (CBDL) or sham-operated Spraque-Dawley rats received brilliant blue G (BBG, a P2X7 antagonist and food additive) or vehicle from the 15th to 28th day after operations, then hemodynamics, mesenteric angiogenesis, portal-systemic shunting, liver fibrosis, and protein expressions of angiogenic and fibrogenic factors were evaluated. The influence of oxidized ATP (oATP, another P2X7 receptor antagonist) on the collateral vasoresponsiveness to arginine vasopressin (AVP) was also surveyed. BBG decreased superior mesenteric artery (SMA) flow, portal-systemic shunting, mesenteric vascular density, and mesenteric protein expressions of vascular endothelial growth factor (VEGF), VEGF receptor 2 (VEGFR2), phospho (p)-VEGFR2, platelet-derived growth factor (PDGF), PDGF receptor beta (PDGFRβ), cyclooxygenase (COX)-1, COX-2, and endothelial NO synthase (eNOS) in CBDL rats. BBG also ameliorated liver fibrosis and down-regulated hepatic interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), PDGF, IL-1β, transforming growth factor-beta (TGF-β), p-extracellular-signal-regulated kinases (ERK), and alpha-smooth muscle actin (α-SMA) expressions in CBDL rats. The collateral vasocontractility to AVP was enhanced by oATP. oATP down-regulated eNOS, inducible NOS (iNOS), VEGF, Akt, p-Akt, and nuclear factor-kappa B (NF-κB) expressions in splenorenal shunt, the most prominent intra-abdominal collateral vessel in rodents. P2X7 antagonism alleviates splanchnic hyperemia, severity of portal-systemic shunting, mesenteric angiogenesis, liver fibrosis, and enhances portal-systemic collateral vasoresponsiveness in cirrhotic rats. P2X7 blockade may be a feasible strategy to control cirrhosis and complications.

Caffeine ameliorates hemodynamic derangements and portosystemic collaterals in cirrhotic rats

Portal hypertension (PH), a pathophysiological derangement of liver cirrhosis, is characterized by hyperdynamic circulation, angiogenesis, and portosystemic collaterals. These may lead to lethal complications, such as variceal bleeding. Caffeine has been noted for its effects on liver inflammation, fibrogenesis, and vasoreactiveness. However, the relevant influences of caffeine in cirrhosis and PH have not been addressed. Spraque-Dawley rats with common bile duct ligation-induced cirrhosis or sham operation received prophylactic or therapeutic caffeine treatment (50 mg/kg/day, the first or 15th day since operation, respectively) for 28 days. Compared to vehicle (distilled water), caffeine decreased cardiac index, increased systemic vascular resistance, reduced portal pressure (PP), superior mesenteric artery flow, mesenteric vascular density, portosystemic shunting (PSS), intrahepatic angiogenesis, and fibrosis without affecting liver and renal biochemistry. The beneficial effects were reversed by selective adenosine A1 agonist N6-cyclopentyladenosine (CPA) or A2A agonist GCS21680. Both prophylactic and therapeutic caffeine treatment decreased portal resistance and PP in thioacetamide (200mg/kg, thrice-weekly for 8 weeks)-induced cirrhotic rats. Caffeine down-regulated endothelial nitric oxide synthase, vascular endothelial growth factor (VEGF), phospho-VEGFR2, and phospho-Akt mesenteric protein expression. Caffeine adversely affected viability of hepatic stellate and sinusoidal endothelial cells, which was reversed by CPA and GCS21680. On the other hand, caffeine did not modify vascular response to vasoconstrictors in splanchnic, hepatic, and collateral vascular beds.

CONCLUSIONS

Caffeine decreased PP, ameliorated hyperdynamic circulation, PSS, mesenteric angiogenesis, hepatic angiogenesis, and fibrosis in cirrhotic rats. Caffeine may be a feasible candidate to ameliorate PH-related complications in cirrhosis.

Molecular mechanisms of circulatory dysfunction in cirrhotic portal hypertension

Acute or chronic insults to the liver are usually followed by a tissue repairing process. Unfortunately, this action, in most cases, is not effective enough to restore the normal hepatic structure and function. Instead, fibrogenesis and regenerative nodules formation ensue, which are relatively nonfunctioning. The common final stage of the process is liver cirrhosis with increased intrahepatic resistance to portal venous blood flow. Throughout the entire course, the extrahepatic circulatory dysfunction, including increased splanchnic blood flow, elevated portal venous blood flow and pressure, decreased splanchnic and peripheral vascular resistance, tachycardia, and increased cardiac output, are noted and denoted as portal hypertension with hyperdynamic circulatory dysfunction. When such a condition is established, patients may suffer from fatal complications such as gastroesophageal variceal hemorrhage, hepatic encephalopathy, or hepatorenal syndrome. The cause of such a circulatory dysfunction is not fully elucidated. Nevertheless, clarification of the pathophysiology definitely contributes to the control of portal hypertension-related complications. Herein, the molecular mechanism of this intriguing disaster is reviewed and discussed.

Diabetes enhances the intrahepatic vascular response to endothelin-1 in cirrhotic rats: association with the ETA receptor and pERK up-regulation

BACKGROUND & AIMS

Cirrhosis is characterized by increased intrahepatic vascular resistance and enhanced vasocontractile responsiveness that impedes portal inflow and elevates portal pressure, in which endothelin-1 (ET-1) plays a role. Diabetes and glucose influence vasoresponsiveness but their impact on the intrahepatic vascular bed in cirrhosis is unknown. To investigate intrahepatic ET-1 vasoresponsiveness in cirrhotic rats with and without diabetes and to explore the underlying mechanisms.

METHODS

Spraque-Dawley rats received common bile-duct ligation (BDL) to induce cirrhosis. Streptozotocin was injected to induce diabetes in the BDL rats (BDL/STZ). In situ liver perfusion was performed to obtain the ET-1 concentration-response curves. The basic hemodynamics and hepatic protein expressions of ET-1 receptors, pERK, ERK, pAkt, Akt, iNOS, eNOS, peNOS and calmodulin were evaluated. The circulating concentrations of N-terminal pro-brain natriuretic peptide (NT-ProBNP), blood urea nitrogen (BUN) and creatinine were also determined.

RESULTS

Body weight, mean arterial pressure, heart rate and survival rate were significantly decreased in the BDL/STZ rats. The perfusion pressure changes in response to ET-1 were higher in the BDL/STZ group for all perfusates. ETA receptor and pERK expressions were enhanced in the BDL/STZ group. The circulating concentrations of NT-ProBNP, BUN and creatinine, as well as SMA flow, were not significantly different between the BDL and BDL/STZ groups.

CONCLUSION

Cirrhotic rats with diabetes showed higher intrahepatic ET-1 vasoresponsiveness than normoglycemic cirrhotic rats. This effect is not affected by changes in perfused glucose concentration and may be related, at least in part, to intrahepatic ETA R receptor and pERK over-expression.

Resetting tremor by single and paired transcranial magnetic stimulation in Parkinson's disease and essential tremor

OBJECTIVE

The pathogenesis of tremor in Parkinson's disease (PD) and essential tremor (ET) is not fully understood. This study tested the role of primary motor cortex (M1), supplementary motor area (SMA) and cerebellar cortex on PD and ET tremor by single- and paired-pulse transcranial magnetic stimulation (TMS).

METHODS

Ten PD patients with resting tremor, six of them also with postural tremor, and ten ET patients with postural tremor were studied. Randomized single- and paired-pulse TMS with an interstimulus interval of 100 ms were delivered over M1, SMA and cerebellum. TMS effects were evaluated by calculating a tremor-resetting index (RI).

RESULTS

Single- vs. paired-pulse TMS showed no difference. M1-TMS and SMA-TMS but not by cerebellar TMS induced a significant RI in PD and ET. M1-TMS resulted in a significantly higher RI in PD than ET. Furthermore, M1-TMS in PD but not in ET resulted in a significantly higher RI than SMA-TMS.

CONCLUSIONS

Findings suggest a stronger involvement of M1 in resting and postural tremor in PD than postural tremor in ET.

SIGNIFICANCE

RI provides a useful marker to explore the differential functional role of M1, SMA and cerebellum in PD vs. ET tremor.

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.