bluuebunny/crossref_metadata_2025 huggingface dataset:
P: 40 Potassium Deficiency Compromises Urea Synthesis and Markedly Increases Ammonia in Rats
Authors: Mikkelsen Anne Catrine B. , Thomsen Karen Louise , Aamann Luise , Vilstrup Hendrik , Aagaard Niels Kristian
Published: September 2019

BACKGROUND:

Potassium deficiency decreases gene expression, synthesis of proteins, and growth in plants, bacteria, rodents and humans.1–4 The effect of hypokalemia on liver protein synthesis is scarcely described. Early studies have established an association between hypokalemia and development of hepatic encephalopathy in chronic liver disease.5,6 We investigated the effects of potassium deficiency on synthesis of liver proteins including urea cycle enzymes and the regulation of urea synthesis in rats.

METHODS:

Female Wistar rats were fed a K+-free diet for 13 days. Half of the rats were then repleted with K+ for one week following depletion. K+-depleted and -repleted rats were compared to free-fed and pair-fed controls. We examined the urea cycle enzyme mRNAs and proteins in liver tissue, the in vivo Capacity of Urea-Nitrogen Synthesis (CUNS) and plasma ammonia concentrations. Also, we measured hepatic albumin gene and protein expression, and potassium levels in plasma, liver, kidney and muscle tissues.

RESULTS:

The diet induced hypokalemia of 1.9 ± 0.4 mmol/L compared to pair-fed controls (3.6 ± 0.2 mmol/L). Muscle and kidney tissue potassium concentrations were decreased, but unchanged in liver tissue. Gene expression of albumin and two out of five urea cycle enzymes were moderately decreased, whereas protein expressions of albumin, the urea cycle enzymes, and glutamine synthetase were normal. However, CUNS was reduced by 33%. Plasma ammonia concentrations were eight-fold elevated to 235 (95% CI: 194–287) µmol/L compared to pair-fed controls 29 (95% CI: 26–32) µmol/L. Repletion of potassium normalized the changes.

CONCLUSIONS:

Hypokalemia markedly increased plasma ammonia concentrations. The capacity for urea synthesis was impaired, but only moderately so, and further studies are needed to fully explain the causes of hyperammonemia.
P: 45 Increased Iba-1 Expression in an Autopsied Brain Samples of ALF & Chronic Liver Disease Patients With Hepatic Encepahlopathy
Authors: Chopra Madhu , Vasishta Rakesh K. , Chakraborti Anuradha , Duseja Ajay , Chawla Yogesh , Dhiman Radha K.
Published: September 2019

BACKGROUND:

Systemic inflammation both in acute liver failure (ALF) and patients with cirrhosis and hepatic encephalopathy (HE) leads to microglial activation and an increase in oxidative stress. Iba-1 has been found to be a highly specific marker expressed in microglial cells in animal models. We studied Iba-1 expression in the brains of patients with ALF and CLF with hepatic encephalopathy and the control patients without any neurological disease.

METHODS:

Autopsied frontal cortex samples were obtained from 5 patients with ALF due to viral hepatitis (HEV, HBV flare) or toxic liver injury (ATT induced) or mushroom poisoning. 7 patients with cirrhosis and HE and 7 controls were obtained. Expression of Iba-1 mRNA was investigated by real-time PCR using appropriate molecular probes and protein expression was assessed using immunohistochemistry using commercially available polyclonal antibodies and measure the intensity with the help of H-score.

RESULTS:

Iba-1 immunostaining highlights the microglial cells in the grey matter of the brain in ALF patients (H-score = 2000) as compared to the patients with cirrhosis and HE (H-score = 450) and to controls (H-score = 300). ALF grey matter specifically highlights the microglial nodule, and faint cytoplasmic hue is also noted in the neurons. Gene expression studies show the increased fold change in Iba-1 in ALF (fold change = 4.08, P = 0.11) and in patients with cirrhosis and HE (fold change = 1.1, P = 0.84) patients when compared with controls, though not statistically significant.

CONCLUSIONS:

These results demonstrated the increased microglial activation as well as the number of microglial cells in the ALF patients that can contribute to neuroinflammation.
P: 46 Ammonia Is an Independent Biomarker of Poor Outcomes in Patients With Advanced Cirrhosis on the Transplant Waiting List
Authors: Alexandrin Gonçalo , Domingues Tiago D. , Bernal William , Shawcross Debbie L.
Published: September 2019

BACKGROUND:

Ammonia plays a pivotal role in the development of hepatic encephalopathy (HE) and brain oedema in acute liver failure and is a poor prognostic biomarker. However, its utility as a prognostic biomarker in patients with cirrhosis remains unclear as there is no direct correlation with hyperammonemia and the manifestation of HE per se. It has recently been demonstrated that blood ammonia levels correlate with organ failure and are an independent risk factor for mortality in patients with cirrhosis and acute decompensation. The aim of this study was to determine whether ammonia levels in patients with advanced cirrhosis awaiting liver transplantation influence waiting list outcomes.

METHODS:

A retrospective observational study of 300 sequential cirrhotic adult patients listed for liver transplantation between January 2015 and December 2018 was undertaken. All patients had an arterial ammonia measured at the time of assessment for transplant. All patients were closely followed up until death or transplantation. The main outcomes were hospital admissions (and number of organ failures), infection and mortality. Chronic Liver Failure-Sequential Organ Failure Assessment criteria were used to determine the presence of organ failures. For the transplanted patients, post-op complications were recorded.

RESULTS:

200 (66.7%) were male with mean age of 54.29 ± 10.4. Mean follow-up time was 722.6 days. 266 (88.7%) patients were transplanted, 15 (5.0%) were de-listed for being too sick for transplant or following clinical improvement, 14 (4.7%) died on the list and 5 (1.6%) were still active on list. 97 (32.3%) patients were hospitalized on the waiting list and 60 (20%) had evidence of at least one infection. On multivariate analysis, ammonia correlated with hospitalisation (P < 0.001), infection (P < 0.001) and all-cause mortality (P = 0.00135). Of the patients that had at least one hospital admission, ammonia was an independent predictor of the presence of acute-on-chronic liver failure (ACLF) (P = 0.01811). For the transplanted patients, ammonia levels correlated with the presence of post-op complications (P < 0.001).

CONCLUSIONS:

In this retrospective study, arterial ammonia at the time of listing for liver transplantation was an independent predictor of hospitalisation, ACLF, infection and mortality. These data suggest that blood ammonia may be an important determinant of wait-list survival and further prospective studies are warranted.
P: 47 Risk of Recurrent Hepatic Encephalopathy (HE) in Patients With Liver Cirrhosis: A German Registry Study
Authors: Gabriel Maria M. , Kircheis Gerald , Hardtke Svenja , Markwardt Daniel , Buggisch Peter , Mix Heiko , Grüngreiff Kurt , Welzel Tanja , Kälsch Julia , Hartmann Heinz , Gerbes Alexander , Weber Kristina , Wedemeyer Heiner , Weissenborn Karin
Published: September 2019

BACKGROUND:

Patients with Hepatic Encephalopathy (HE) show a low quality of life, recurrent hospitalizations and an increased mortality. We aimed to assess the natural course of patients after a recent HE-episode under the conditions of the German health system, as respective data were not available.

METHODS:

Fifteen sites from Germany - 8 of them liver transplant (LT) centers - took part in an observational prospective study including cirrhotic patients who had been hospitalized due to an acute episode of HE within 3 months before recruitment. Age < 18 years, no liver cirrhosis, malignancies and current hospitalization were exclusion criteria. Demographic and clinical data, health related quality of life (HRQoL) score SF-36, psychometric hepatic encephalopathy score (PHES) and critical flicker frequency (CFF) were assessed and monitored quarterly for one year. Primary endpoint was a novel clinical manifestation of HE necessitating hospital admission. Secondary endpoints were the combined endpoint of hospital admission for a novel HE episode and/or death, the dynamics of the West Haven Criteria (WHC) as well as changes in CFF, PHES and SF-36.

RESULTS:

A total of 115 patients were recruited. Fourteen patients (12.4 %) died during the study period due to complications of liver cirrhosis other than HE. For 67 subjects follow-up data were available in accordance with the protocol. After a median of 113 days half of the per protocol cohort (N = 34) was re-admitted due to a recurrent manifestation of HE. The patient groups with and without re-hospitalization differed significantly regarding recruitment sites (LT centers vs no LT centers) (P = 0.005), interval from discharge to recruitment (P = 0.007), history of more than 4 HE relapses prior to recruitment (P = 0.029), SF-36 mental score (P = 0.046) and PHES ≤ −3 (P = 0.004), whereas CFF, clinical (e.g. MELD score, WHC grade) and laboratory data did not differ. Of note, CFF performance was correct only in about half of both, the total and the per protocol group. Patients with incorrect CFF performance had worse PHES results than those with valid CFF measurement. Multiple logistic regression analysis revealed a PHES test result of ≤−3 as an independent risk factor for re-hospitalization (P = 0.046).

CONCLUSIONS:

Mortality in our cohort is comparatively low. Despite advanced treatment strategies, patients with a history of HE are still sincerely jeopardized to develop recurrent clinical HE. The PHES test appears useful for detection, monitoring and stratification of recurrent HE. Patients with PHES ≤−3 at baseline had an increased risk of deterioration.
P: 48 Nonselective Beta-blocker Use Is Associated With Increased Hepatic Encephalopathy-Related Readmissions in Patients With Cirrhosis
Authors: Amin Fallahzadeh Mohammad , Bizzarri Daniel , Saracino Giovanna , Rahimi Robert S.
Published: September 2019

BACKGROUND:

Hepatic Encephalopathy (HE) is a reversible syndrome of impaired brain function that is associated with frequent hospitalizations and decreased survival in cirrhotic patients. Nonselective beta-blockers (NSBB) are the mainstay of pharmacologic treatment for portal hypertension and prevention of variceal bleeding. Due to their effects on hepatic blood flow, we hypothesized that NSBB use would decrease portal flow, leading to increased HE related hospitalizations independent of liver disease severity. This study was done to assess the effect of NSBB use on HE-related readmissions.

METHODS:

We examined all the patients with cirrhosis admitted at Baylor University Medical Center between January 2013 and July 2018. The outcome measure of HE-related readmissions was analyzed in patients taking NSBB vs. patients not taking NSBB using cox proportional hazard regression model. The model was adjusted for age, sex, Model for End-Stage Liver Disease (MELD) score, selective beta-blocker (SBB) use, ascites, and history of esophageal varices (EV) and transjugular intrahepatic portosystemic shunt (TIPS). The Kaplan-Meier method and log-rank test were used to compare the cumulative incidence of HE-related readmissions between the aforementioned groups.

RESULTS:

There were 393 patients in this study with a mean age of 58.1 ± 10.2 years and a male predominance. The mean MELD score was 19.6 ± 7.7. The median time between the first admission and future readmission was 1.9 months with interquartile range of 4.8 months. The cumulative incidence of HE-related readmissions was significantly higher in patients taking NSBB compared with patients who were never prescribed NSBB (P < 0.001) (Figure 1). This effect was not seen for patients who were taking SSBs. In multivariate analysis, after adjusting for age, sex, MELD score, SBB use, ascites, history of EV and TIPS, NSBB use was independently associated with increased risk of HE-related re-hospitalizations; Hazard ratio was 2.82 (95% confidence interval: 1.81–4.41).

CONCLUSIONS:

NSBB use is independently associated with increased HE-related readmissions in patients with cirrhosis, regardless of liver disease severity. Thus, NSBBs should be used cautiously in patients who have experienced a prior HE episode. However, further prospective studies are needed to determine the impact of NSBB on portal hypertension complications.
P: 50 Developing a New Animal Model of Episodic Hepatic Encephalopathy
Authors: Tamnanloo Farzaneh , Ochoa-Sanchez Rafael , Tremblay Mélanie , Rose Christopher F.
Published: September 2019

BACKGROUND:

Hepatic encephalopathy (HE) is a neuropsychiatric syndrome, a major complication of chronic liver disease (CLD/cirrhosis). The primary cause of hospital admissions for cirrhotic patients is an overt episode of HE. Precipitating factors of HE frequently lead to an increase in blood ammonia. Patients who have experienced multiple episodes of HE are associated with persisting neurological complications post-liver transplantation. Currently, the impact of HE episodes on neurological integrity is unknown. We hypothesize that multiple episodes of HE will accelerate and/or intensify neurological deterioration. To date, an animal model of episodic HE is lacking. Therefore, our goal was to characterize an animal model of episodic HE (precipitated with ammonia) and to evaluate the impact of cumulative episodes on neurological status in cirrhotic rats.

METHODS:

Animal model of CLD and HE: 6-week bile-duct ligation (BDL) rats, and Sham-operated controls were used. BDL and Sham rats were divided in two groups, episodic and non-episodic. Injection (i.p) of ammonium acetate was used to induce episodes of overt HE (pre-coma; loss of righting reflex) every 4 days starting 3-weeks post-BDL surgery (total 5 episodes). Saline was injected as vehicle for non-episodic groups. Two days following the last HE episode, we assessed motor-coordination (RotaRod), anxiety (elevated plus maze, EPMT), as well as short-term and long-term memory (novel object recognition) in all groups. Upon sacrifice, plasma ammonia was measured.

RESULTS:

The concentration of ammonia required to induce an episode of overt HE in BDL rats lessened with each subsequent episode, ranging from 7 to 4.5 mmol/kg. Short-term memory (P < 0.05) and motor-coordination (P < 0.05) were impaired in both non-episodic and episodic BDL groups compared to respective Sham-operated controls. Long-term memory impairment (P = 0.06) and increased anxiety (+60.0%, P < 0.05) were exclusively found in episodic BDL rats compared to non-episodic BDL rats. Moreover, there was an increase in blood ammonia (+30.4%, P = 0.06) in episodic compared to non-episodic BDL rats, suggesting that although episodic-BDL rats recover from each HE episode, baseline (pre-episode) ammonia remain higher than non-episodic BDL rats.

CONCLUSIONS:

Cumulative HE episodes escalate neurological impairments in cirrhotic-BDL rats. Thus, this new episodic HE model represents a good approach to explore the pathological mechanism arising from multiple episodes, as well as further investigate whether higher hyperammonemia and/or increased brain sensitivity to ammonia is responsible for more complex neurological manifestations in episodic-BDL rats. Moreover, this model is an excellent platform to investigate novel therapies to prevent/treat episodic HE.
P: 52 Visual Analysis of the EEG Performs Better Than Standard Spectral Analysis in the Clinical Setting
Authors: Garciá-Garciá Raquel , Morgan Marsha Y. , Jackson Clive D.
Published: September 2019

BACKGROUND:

The electroencephalogram (EEG) provides objective information useful for detecting and monitoring hepatic encephalopathy (HE); its acquisition does not require patient co-operation and there are no learning effects. The ISHEN guideline (Guérit et al, 2009) states that 'the EEG classification based on visual pattern recognition, although informative, does not allow reliable grading' and that 'quantitative (computer-based) analysis may improve the reliability of EEG assessment'. However, this recommendation was rated as weak and uncertain. This study aims to compare the performance of visual and spectral analysis of the EEG for the diagnosis of any degree of HE.

METHODS:

The study population comprised of 137 healthy controls (53% men: mean [range] age 39 [17–75] yr) and 226 patients with cirrhosis (66% men; mean age 54.8 [26–80] yr) classified, based on clinical status and PHES results, as neuropsychologically unimpaired (n = 127) or as having minimal (n = 21) or overt (n = 78) HE. A researcher with no previous experience received basic training in EEG analysis. She was asked to select 60 to 100 sec of recording, preferably from the P3-P4 montage, from the 403 anonymized patient/control EEG records and to estimate the visual wave frequency in a representative epoch, marking her selection. Spectral analysis of the EEG was undertaken on the same 60 to 100 sec of recording and the mean dominant frequency (MDF) and %theta power obtained (Jackson et al, 2016). The performances of the visual and spectral assessment of the EEG for the diagnosis of any degree of HE were compared.

RESULTS:

The diagnostic performance for the diagnosis of any degree of HE was comparable between the visual assessment of background activity (ROC: threshold 8.75 Hz; AUC 0.84; sensitivity 77.4%; specificity 74.5%) and the spectral %theta power (ROC: threshold 23%; AUC 0.81; sensitivity 74.8%; specificity 78.4%). However, the visually assessed background activity provided better separation of the patients in relation to their neuropsychiatric status that either of the spectral variable. Thus, significant differences were observed in the visual background activity between all patient groups and healthy controls and between patients with minimal and overt HE, whereas significant differences in spectral variables were only observed in the patients with overt HE (Figure 1).

CONCLUSIONS:

The ISHEN statement that 'visual assessment of the EEG, does not allow reliable grading' and that 'quantitative analysis may improve the reliability of EEG assessment is not supported by the findings in this study.
P: 53 Extent of Sarcopenia Does Not Correlate With Degree of Minimal Hepatic Encephalopathy in patients on Treatment for Hepatric Encephalopathy
Authors: Rathi Sahaj , Montagnese Sara , Brocco Silvia , Zarantonello Lisa , Formentin Chiara , Mangini Chiara , Merkel Carlo , Angeli Paolo , Stramare Roberto , Amodio Piero
Published: September 2019

BACKGROUND:

Minimal hepatic encephalopathy affects over half of the patients with cirrhosis. It leads to deterioration of quality of life due to cognitive deficit. Both presence of sarcopenia and portosystemic shunts have been implicated in development of minimal hepatic encephalopathy. We retrospectively assessed the significance of sarcopenia and presence of portosystemic shunts in patients with minimal hepatic encephalopathy.

METHODS:

Patients with cirrhosis of liver attending the liver clinic at University of Padua underwent a detailed elective outpatient assessment for neurocognitive function. This included Psychometric Hepatic Encephalopathy Score (PHES), computer based tests, and EEG. We then selected patients who underwent a computed tomography for any reason within 3 months of the neurocognitive assessment. The degree of sarcopenia and presence of portosystemic shunts was evaluated on the scan. Presence of more than one shunt was accounted and adjusted for appropriately using a physiological approach previously described.

RESULTS:

A total of 120 patients had a CT scan within 3 months of the neurocognitive assessment. Of these, 100 were found to be suitable for analysis. Mean age of the patients was 59 ± 9.6 yrs and 73% were males. Median Child Pugh score was 8 (IQR 6–10) and MELD was 12 (IQR 10–18). Alcohol and viral etiologies responsible for 40% and 39% cases respectively. Based on Psychometric Hepatic Encephalopathy Score (PHES), 39% had minimal hepatic encephalopathy. Medication details were available for 87 patients, 70% of whom were on some form of treatment of hepatic encephalopathy with lactulose, antibiotics, or probiotics. The degree of cognitive dysfunction (PHES) correlated significantly with education (r = 0.33), shunt size (r = −0.45), and degree of hyperammonemia (r = −0.48), but not with sarcopenia or degree of hepatic dysfunction. Correlation between total effective shunt size and PHES was more pronounced in women (r = −0.68). Upon multivariate analysis, none of these variables predicted PHES. EEG mean dominant frequency correlated significantly with total effective shunt size (r = −0.30), ammonia (r = −0.34), and Child-Pugh score (r = −0.38). None of the parameters significantly correlated with critical flicker frequency. There was no difference in the degree of sarcopenia among patients with and without MHE or history of overt HE. Moreover, degree of sarcopenia did not correlate with PHES, critical flicker frequency, ammonia level, or Child-Pugh score. Effective size of portosystemic shunt was higher in patients with MHE.

CONCLUSIONS:

Among patients with cirrhosis on anti-encephalopathy treatment, presence of sarcopenia does not correlate with neurocognitive parameters. Presence of large portosystemic shunts correlated with neurocognitive impairment.
P: 57 Thrombospondin-1 Worsens Azoxymethane-Induced Hepatic Encephalopathy Through Activation of Transforming Growth Factor Beta 1
Authors: Frampton Gabriel , Jefferson Brandi , Grant Stephanie , DeMorrow Sharon , McMillin Matthew
Published: September 2019

BACKGROUND:

Acute liver failure (ALF) is a consequence of severe hepatic injury and is associated with poor clinical outcomes. Patients with ALF often present with neurological complications, called hepatic encephalopathy (HE). Transforming growth factor beta 1 (TGFβ1) is upregulated following liver damage and we have shown that TGFβ1 drives HE progression. Thrombospondin-1 (TSP-1) can activate latent TGFβ1 and therefore, we hypothesize that hepatic-derived TGFβ1 is activated by TSP-1, which exacerbates liver damage and HE associated with azoxymethane-induced ALF.

METHODS:

Male C57Bl/6 mice were treated with azoxymethane (AOM; 100 mg/kg BW) to induce ALF. Six hours after AOM injection, mice were injected with the TSP-1 antagonist LSKL (30 mg/kg) or SLLK as control. In parallel, male TSP-1 knockout mice and wild-type (WT) controls were injected with AOM. In AOM-treated mice, cognitive impairment was monitored by reflex and ataxia measurement. Liver histology was assessed by hematoxylin and eosin staining and serum transaminases were measured. Cleaved caspase 3 immunohistochemistry and TUNEL staining were used to assess apoptosis in liver tissue. Hepatic inflammation was determined by measuring IL-1β, IL-6 and TNFα expression via real-time PCR and ELISA assays. TGFβ1 and TSP-1 expression were assessed in liver, serum and cortex by immunoblotting, immunohistochemistry and real-time PCR. Cerebral edema and microglia activation were assessed and neuroinflammation was measured by assessing IL-1β, IL-6 and TNFα expression in the cortex.

RESULTS:

Mice injected with AOM had elevated hepatic, circulating and cortical TGFβ1 and TSP-1 levels, with the cortex only having elevated TGFβ1. LSKL-treated mice and TSP-1 knockout mice administered AOM had reduced activation of hepatic TGFβ1, hepatocyte apoptosis, inflammation, and hepatic injury compared to AOM and SLLK-treated mice or WT AOM-treated mice. LSKL-treated and TSP-1 knockout mice administered AOM had an increased latency to reach coma compared to SLLK-treated or WT mice. LSKL-treated mice and TSP-1 knockout mice had reduced TGFβ1 expression, less cerebral edema, attenuated microglia activation, and decreased expression of IL-1β, IL-6 and TNFα in the cortex compared to control mice.

CONCLUSIONS:

TGFβ1 and TSP-1 were elevated in the livers and serum of AOM-treated mice and strategies employed to reduce TSP-1 signaling reduced liver damage and neuroinflammation in the AOM mouse model of HE. Therefore, targeting TSP-1 signaling may be a novel therapeutic target for the management of both ALF and HE following acute liver injury.
P: 59 Supplementation With Synbiotics and/or Branched Chain Amino Acids in Hepatic Encephalopathy: A Pilot Randomised Placebo-Controlled Clinical Study
Authors: Vidot Helen , Cvejis Erin , Finegan Liam , Shores E. Arthur , Strasser Simone , McCaughan Geoffrey , Carey Sharon , Shackel Nicholas
Published: September 2019

BACKGROUND:

Hepatic encephalopathy (HE) is common in patients with cirrhosis and characterised by reduced hepatic ammonia clearance. This is accompanied by alterations in gut bacteria and increased intestinal epithelial permeability that may be ameliorated with synbiotics (pro- and pre-biotics). Branched chain amino acids (BCAAs) are thought to have a role in the detoxification of ammonia. We investigated the effects of the administration of Synbiotics and/or BCAAs in treating HE.

METHODS:

Methods Participants with minimal HE (MHE) were randomised in an placebo-controlled study to receive synbiotics, BCAAs, or a combination of BCAAs and Synbiotics. The investigators were blinded to the supplements at all times. Relevant biochemical and nutritional data and depression and anxiety scores (DASS-21) were collected at entry, 4 weeks, and on completion, at 8 weeks. The Trail Making Test (TMT) and Inhibitory Control Test (ICT) were used to assess cognitive function in HE. Results were analysed using linear mixed effects regression analyses

RESULTS:

Sixty-one participants with MHE determined by the treating physician, confirmed on psychometric testing (TMT and ICT) and who were taking 63 ± 6 mLs lactulose/day were enrolled. Recruitment was limited by the widespread introduction of rifaximin in Australia during the recruitment period. The final intention to treat analysis included 49 participants who returned for at least 1 follow-up review. The mean age was 55.8 ± 6.1 years and 86% were males. Despite evidence of a placebo effect, there was significant improvement in TMT B (P ≤ 0.05) (Figure 1a) and ICT weighted lures (P = 0.007) (Figure 1b) in participants who received combined synbiotics/BCAAs treatment compared to placebo at study completion. Cognitive improvement occurred without a significant change in ammonia levels.

CONCLUSIONS:

To the best of our knowledge, this study is the first to report an improvement in cognitive function and, therefore, executive function in individuals with decompensated cirrhosis and MHE in response to oral supplementation with combined synbiotics and BCAAs. A larger study which includes measures of dysbiosis and intestinal epithelial permeability is needed to confirm these results.
P: 60 Characterization of a Novel Mouse Model of Type A Hepatic Encephalopathy
Authors: Williams Elaina , Grant Stephanie , Petrescu Anca , Frampton Gabriel , McMillin Matthew , DeMorrow Sharon
Published: September 2019

BACKGROUND:

Type A hepatic encephalopathy (HE) describes the neurological complications caused by acute liver failure. Research into Type A HE has been hampered as existing models cause severe and rapid HE, with a limited therapeutic window and high mortality, that do not reflect all features observed in patients. The aim of this study was to establish and characterize an alternative mouse model of Type A HE that has a more protracted timeline of pathology.

METHODS:

Male C57Bl/6 mice were fed standard rodent chow enriched with 0.1% 3,5-diethoxycarbonyl-1,4-dihydrocollidine and 10% ammonium acetate (DDC + NH4). Neurobehavioral indices and neuromuscular deficits were assessed by open field test, rotarod, grip strength test and gait analysis. Serum, liver and brain tissue were collected after 13 days of DDC + NH4 feeding. Liver damage was assessed by serum chemistry and H&E staining. Serum and cortical ammonia and total bile acid content were assessed with colorimetric assays. Cerebral edema was assessed using the wet weight/dry weight method. Microglia activation was assessed by Iba1 immunofluorescence. The expression of proinflammatory cytokines were assessed by qPCR and EIA.

RESULTS:

DDC + NH4 feeding caused significant neurological and neuromuscular deficits in every test performed commencing after 5–7 days of feeding. The liver damage observed was like a cholestatic hepatitis phenotype of drug-induced liver injury in humans; AST, ALT, alkaline phosphatase and total bilirubin were elevated. Histologically, there was evidence of intrahepatic cholestasis, drug-induced bile duct blockage, ductular reaction and immune cell infiltration, with low incidence of hepatocyte necrosis and little to no discernible fibrosis. Serum and cortical ammonia and total bile acid levels were elevated, and there was increased brain water content, indicating cerebral edema in DDC + NH4 fed mice. Furthermore, there was evidence of microglia activation and increased proinflammatory cytokine expression in the cortex of DDC+NH4 group compared to control diet-fed mice.

CONCLUSIONS:

DDC + NH4 feeding generated key features of Type A HE, with a longer timeline of pathology than the current models. With further characterization, this model may prove an effective and preferable model for pre-clinical studies to identify the pathogenesis or possible treatment options for Type A HE.
P: 72 Hyponatremia Correction in Cirrhosis May Increase the Speed of Complex Information Processing
Authors: Watson Hugh , Guevara Monica , Gines Pere , Vilstrup Hendrik
Published: September 2019

BACKGROUND:

Hyponatremia is frequent in patients with advanced cirrhosis and ascites. A decrease in plasma osmolality exacerbates astrocyte swelling and through this mechanism may worsen cognitive function. Our objective was to determine whether, in patients with cirrhosis and ascites, an increase in plasma sodium (spontaneous or induced by an aquaretic) leads to an improvement in cognitive function.

METHODS:

250 patients with liver cirrhosis and ascites were included in two double-blind, randomised, multicentre clinical studies of satavaptan (a vasopressin V2 antagonist). Patients were included after a "wash-out period" (one week on controlled sodium intake and spironolactone 100 mg/d) and received either placebo (n = 61) or satavaptan (n = 189) at three different doses (5, 12.5, 25 mg/d). Patients completed the trail-making test (TMT) at baseline and at 5–7 and 14–28 days of follow-up. The TMT (scored in seconds) assesses speed of information processing and is considered a test of simple (part A) and complex attention (part B). Improvement of hyponatraemia was defined as an increase in plasma sodium >5 mmol/l or to a value >135 mmol/l.

RESULTS:

At inclusion into the studies, patients with normonatremia exhibited better results on the TMT-A and TMT-B that could not be explained by differences on age. This group also exhibited better parameters of liver function (Table 1). Improvement of hyponatremia was associated with shortening on the time needed to complete TMT-B: −20 s vs −6.5 s (P = 0.02), but not TMT-A: −10 s vs −5 s (P = 0.16). Increase in serum osmolality was also associated with better TMT-B scores (P < 0.001 at Day 5-7 and P = 0.033 at Day 14–28), but this was not shown for TMT-A. Liver function parameters remained stable in both groups of patients. Improvement of hyponatremia at Day 5 was most commonly seen in patients that received satavaptan (59.7%, n = 82) than in those treated with placebo (18.5%, n = 28). Median changes in TMT scores with satavaptan (all doses pooled) compared to placebo were: TMT-A −10 s vs 0 s (P = 0.08) and TMT-B −20 s vs −7.5 s (P = 0.12).

CONCLUSIONS:

Improvement of hyponatremia in cirrhosis was associated with an increase in the speed of complex information processing. Improvement of hyponatremia was achieved more frequently with satavaptan treatment, which showed a trend towards better results on cognitive function.
P: 73 Acetate Attenuates the Astrocyte Swelling and Brain Edema in Severe Liver Failure
Authors: Moriyama Mitsuaki , Minamihata Tomoki , Jayakumar Arumugam R. , Norenberg Michael D.
Published: September 2019

BACKGROUND:

Astrocyte swelling and brain edema are major complications of severe liver failure. Ammonia plays a major role in the development of astrocyte swelling/brain edema in this condition. However, current therapies have not thus far improved the outcome of liver failure induced astrocyte swelling/brain edema. Since acetate has been shown to have neuroprotective effect in other neurological conditions, likely though increased energy production, we examined whether acetate similarly protect cell swelling in cultured astrocytes post-ammonia exposure. We also examined whether treatment of rats with glyceryl triacetate (GTA), an acetate precursor, which is known to increase circulating, as well as tissue levels of acetate, alleviates the brain edema induced by the liver toxin thioacetamide (TAA).

METHODS:

Astrocyte cell volume was estimated by measuring the intracellular water space using 3-O-methylglucose. Brain water content was measured by using the gravimetric method.

RESULTS:

Exposure of astrocyte cultures to pathological concentrations of ammonia (NH4Cl; 5 mM) for 24 h significantly increased cell swelling. Co-treatment of ammonia with acetate reduced such swelling in a dose-dependent manner. Further, treatment of rats with TAA (250 mg/kg bw) for 3 days increased the brain water content, and that pretreatment of (intragastrically) TAA-treated rats with GTA (7.5 g/kg bw), attenuated brain edema.

CONCLUSIONS:

These findings strongly suggest that acetate supplementation will exert salutary effects in reducing brain edema in patients with severe liver failure.
P: 74 Cholestasis Decreases Dendritic Spine Density in a Rat Hippocampal Organotypic Culture
Authors: Giovannoni Laurianne , De Roo Mathias , Braissant Olivier , Henry Hugues , Cudalbu Cristina , Vutskits Laszlo , McLin Valérie
Published: September 2019

BACKGROUND:

Executive functioning impairment in children with cholestatic liver disease is increasingly recognized. Injury to developing neuronal networks could be an underlying mechanism. Given that the CSF of rat pups following bile duct ligation is highly concentrated in ammonia, murocholic and taurocholic acids, we hypothesized that cholestasis may significantly alter density of synaptic contacts onto pyramidal neurons, known to be essential in the development of executive functioning.

METHODS:

Transverse hippocampal organotypic slice (400 µm thick) were harvested from 6–7-day-old Wistar rats. They were maintained for 15 days in a CO2-incubator (33°C). pc-DNA3.1-EGFP plasmid biolistic transfection was performed 7 days after harvesting. 3 days following transfection, control medium or experimental medium containing 100 µM α-murocholic-acid, 200 µM taurocholic-acid and 2.5 mM ammonium was added to the culture (day 0 of exposure, MIX condition). Confocal microscopy using imageJ was used for to manually count CA1 pyramidal neuron dendritic spines as proxies for excitatory synapses. Static analysis quantified dendritic spines density each day. Dynamic analysis quantified dendritic spines turnover (loss and neo-formation) for each 24 h time-window. Statistical analysis was conducted using PRISM software for multiple t-test or mixed-effect ANOVA.

RESULTS:

Static analysis showed a biphasic profile in MIX condition. During early phase (first 3 days of exposure), we observed >50% decrease in dendritic spine density compared to control (cf Figure 1, P < 0.001). On days 3 to 4), spine density recovered to reach control value. Dynamic analysis showed 15% loss in dendritic spines stability during the early phase of exposure to MIX condition, compared to controls, with comparable low rates of spine turnover. During the late phase of MIX exposure, spine turnover increased significantly in favor of spine neo-formation: spine neo-formation was 10 times higher (0.280 vs 0.023 spines.µm-1, P = 0.033) than controls, while spine loss was 6 times higher in neurons exposed to MIX (0.154 vs 0.026 spines.µm-1, P = 0.0026) than controls.

CONCLUSIONS:

We demonstrate here that mimicking cholestasis ex vivo leads to a biphasic response in spine density of rat hippocampal CA1 pyramidal neurons. Spine density decreases during the first 3-days of exposure to a mix of bile acids and ammonium chloride-owing to decreased in spine stability. This is followed by increased spine turnover with spine neo-formation in excess of spine loss, yielding a final spine density similar to control animals. Whether these new spines are functionally equivalent to controls remains to be determined.
P: 76 Reversible and Irreversible Neurological Complications in Hepatic Encephalopathy
Authors: Tong Xiaoying , Shamaladevi Nagarajarao , Ahmad Anis , Arcuri Jennifer , Norenberg Michael , Jayakumar Arumugam
Published: September 2019

BACKGROUND:

Hepatic encephalopathy (HE) is a major neurological condition that occurs due to acute and chronic liver failure following drug toxicity, viral hepatitis, or exposure to various hepatotoxins. Acute HE (Type A HE) is associated with cerebral edema, increased intracranial pressure, coma and death. Chronic HE (Type C HE) is characterized by mental confusion, behavioral changes, and motor disturbances. It is currently unclear whether HE is reversible or irreversible. We therefore examined whether acute or chronic liver failure is reversible or irreversible in the thioacetamide (TAA) rat model of acute and chronic HE. Accordingly, rats were treated with the liver toxin TAA and brain edema, neurobehavioral, cognitive and motor deficits were measured.

METHODS:

Rats were treated with the liver toxin TAA and brain edema, neurobehavioral, cognitive and motor deficits were measured.

RESULTS:

Treatment of rats with high doses of TAA (to induce acute HE) led to brain edema within 2-3 days. Rats following TAA treatment were examined for longer time-periods. Rats did not exhibit any brain edema, although they expressed neurobehavioral, cognitive and motor deficits without any changes documented in blood and brain ammonia levels, as well as liver failure markers, as compared to normal rats. However, rats that underwent chronic liver failure for 10 days displayed neurobehavioral, cognitive and motor deficits, along with brain structural and molecular events, including reduced levels of astrocytic matricellular proteins, as well as reduced levels of neuronal proteins. We also found a reduction in synaptic density and in dendritic complexity. These changes correlated-well with increased blood/brain ammonia levels and with liver failure markers. However, when TAA treatment was withdrawn (after 10 days), and the rats monitored for longer time periods still showed neurobehavioral, cognitive and motor deficits, as well as defective neuronal integrity, even though blood and brain ammonia levels, as well as liver biochemical and molecular parameters were reversed.

CONCLUSIONS:

These findings strongly suggest that neurobehavioral, cognitive and motor deficits in HE cannot be reversed even when acute or chronic liver failure had been corrected.
P: 79 Central Inhibition of IGFBP3 Attenuates Symptoms of Hepatic Encephalopathy in a Mouse Model of Acute Liver Failure
Authors: Grant Stephanie , Williams Elaina , Petrescu Anca , Reinhart Evan , Blaney Hanna , Frampton Gabriel , McMillin Matthew , DeMorrow Sharon
Published: September 2019

BACKGROUND:

Insulin-like growth factor binding protein 3 (IGFBP3) has a strong binding affinity for IGF proteins and can inhibit the function of IGF by preventing interaction with its receptor. In addition, IGFBP3 can exert IGF-independent effects via direct interaction with a putative IGFBP3 receptor. Little is known about the function of IGFBP3 in the brain, outside of a role in brain cancer development. We have recently demonstrated that IGF1 expression is suppressed in the frontal cortex in a number of rodent models of hepatic encephalopathy (HE) and central administration of recombinant IGF1 attenuates the neurological complications. However, the role of IGFBP3 in the pathogenesis of HE is unknown and is the aim of this study.

METHODS:

C57Bl/6 mice were injected with azoxymethane (AOM) to induce acute liver failure and HE. In parallel, mice were given an intracerebroventricular infusion of the IGFBP inhibitor, NBI31772 for 3 days prior to AOM injection. Cognitive impairment was monitored by reflex response assessment at various time points and neuromuscular deficits were assessed using a grip strength meter. Liver damage was determined by H&E staining and serum chemistry. The expression of IGFBP3 and IGF1 was assessed in the cortex by qPCR, EIA and immunofluorescence using NeuN (neuronal), GFAP (astrocytic) or Iba1 (microglial) antibodies as a counterstain. Microglia activation was evaluated by assessment of field Iba1 staining and microglia cell morphology. Neuroinflammation was also measured by the expression of key proinflammatory cytokines.

RESULTS:

IGFBP3 was predominantly expressed in neurons of the cortex and increased once significant neurological deficits were observed after AOM injection. Pretreatment of mice with the IGFBP inhibitor had no effect on the underlying liver damage, but delayed the onset of neurological symptoms, attenuated the neuromuscular deficits, inhibited neuroinflammation and increased the bioavailability of the neuroprotective IGF1 after AOM injection, suggesting that IGFBP3 may be contributing to the pathogenesis of HE.

CONCLUSIONS:

Elevated cortical IGFBP3 expression contributes to the pathogenesis of HE in AOM-treated mice via a mechanism that may involve increasing IGF1 bioavailability, although IGF1-independent effects can not be ruled out. Targeting IGFBP3 in the cortex may prove promising for the development of adjunct therapies to manage the neurological complications of acute liver failure.
Redes institucionales y desarrollo económico en ciudades pequeñas y medias: El caso de la localidad PUNTA ALTA
Authors: Diez José Ignacio , Lencina Ezequiel , Pong Claudia
Published: September 2019

En las últimas décadas las ciudades de dimensión pequeño y medio han recuperado su protagonismo dentro de los sistemas urbanos, tanto en el ámbito científico como en las estrategias de ordenamiento y desarrollo territorial a escala internacional. Estas localidades están adquiriendo preponderancia como componentes destacados de las políticas regionales, incorporándose como actores claves en las posibilidades de despegue industrial de territorios periféricos. Entre los instrumentos tendientes a promover su crecimiento y consolidación, la literatura especializada destaca la conformación de redes institucionales, como un elemento capaz de incentivar la innovación y el cambio tecnológico. El presente trabajo pretende analizar la dinámica de funcionamiento de la red de organizaciones de apoyo a la producción (OAP’s) de la localidad de Punta Alta (Argentina), con el propósito de entender en qué medida estas instituciones mejoran las condiciones de competencia y desarrollo del territorio.
Desarticulación y fragmentación de iniciativas de desarrollo rural. La experiencia reciente de la provincia se Santiago del Estero, Argentina
Authors: Carrizo Maria Del Carmen , Sili Marcelo
Published: September 2019

Desde la década de los 90 emergieron en Argentina numerosas iniciativas de apoyo al desarrollo agropecuario y rural, muy especialmente en las provincias denominadas extrapampeanas. Estas iniciativas lideradas en gran parte por el Gobierno Nacional se organizaban a través de sus organismos y de programas de financiamiento internacional, y además por otras iniciativas provinciales y locales. Las mismas fueron pasando a través de los años de enfoques sectoriales a enfoques territoriales. Un hecho saliente es que estas iniciativas siempre se mostraron desarticuladas, sin mecanismos de coordinación entre ellas, por lo cual no pudieron generar los impactos que se planificaba y que las comunidades rurales requerían. Este artículo analiza, desde la experiencia de los responsables de los programas de desarrollo, las causas de esta desarticulación y fragmentación de las iniciativas de desarrollo rural en Argentina, poniendo énfasis en el sur de la Provincia de Santiago del Estero.
A brief communication of shispar glacier surge in 2018, hunza river basin, Pakistan
Authors: Hussain Alamgeer
Published: September 2019

Glacier surging is a common phenomenon in the Karakoram region, but the driving mechanisms, their occurrence and its relation to a changing climate remain are unclear. In this study, we use Sentinel imagery to quantify advancement of the Shispar glacier during a surge in 2018. Results reveal that Shispar glacier starts rapid surging from Jun 2018. The peak surge is in August 2018. Our data reveal that glacier dammed the Hassanabad stream as result lake formation in upstream area and drainage of the lake also blocked. The surging is continuing and size of newly formed glacier lake is also increasing day by day. Currently, the inflow to lake is very low due to low melting (negative temperature) from the upstream glacier. This inflow of glacier meltwater will be an increase in the summer season, which may grow in lake size and could pose threats to downstream settlements and infrastructure (irrigation channels, powerhouses and bridge at Karakoram Highway (KKH) in the case of a sudden breach in the form of glacial lake outburst flood (GLOF). Currently the damages the powerhouse channel and damage the irrigation channel of Aliabad Hunza. This study recommended that there is a need for monitoring of glacier lake size and blockage area using remote sensing data i.e. satellite images and UAV.
Phlebotrophic Effect of Graptophyllum Pictum (L.) Griff on Experimental Wistar Hemorrhoids
Authors: Hutagalung Mario Sadar Bernitho
Published: September 2019

Background : The 1st and 2nd degree hemorrhoids is managed non-operatively with the anti-inflammatory and plebothropic drugs. Graptophyllum pictum extract (GPE) has already been used widely in Indonesia to treat hemorrhoid with good result, however, the mechanism is not supported by the molecular research.Objective : This study is intended to study the phlebothropic effects of GPE by measuring the degree of edema and extravassal leucocytes of experimental wistar hemorrhoid.Methods : Experimental study with Randomized Controlled Trial Post-test only design in male wistar rats, weight around 200 gr, induced for the development of a disease-like condition of hemorrhoids by 6% croton oil on the anus for 3 days. Random allocation was performed to divide the 14 wistar rats in 2 groups. Group I as control got normal saline solution, while group II was treated with GPE 100mg/kgbw, started on day 4th for 5 consecutive days. On 9th day blood was extracted from retroorbital fossa and anus was resected up to 2 cm from anal verge and weighted. The degree of anal edema was measured by rectoanal coefficient, that is rasio between anal weight (miligrams) and body weight (grams).Results : Until the end of study, all wistar rat were still alive. The mean (±SD) of body weight   of control group was 173.84 ­(±13.37) and the treatment group was 171.70  (±13.10), and there was no significant differences (p = 0.833). The mean (±SD) of rectoanal coefficient in the treatment group was 2.46 (±0.41) and it was significantly lower than control group  (3.13 ± 0.85) (p = 0.029). The mean (±SD) of extravassal leukocytes in the treatment group was 900.14(±48.09) and it was significantly lower than the control (1003.28 ± 99.30) (p = 0.042).Conclusions : Graptophyllum pictum extract at doses of 100 mg/Kgbw have phlebotonic effect  in decreased edema and extravassal leukocytes.