Optimization and fabrication of porous carbon electrodes for Fe/Cr redox flow cells

Negative electrode development for the NASA chromous/ferric Redox battery is reported. The effects of substrate material, gold/lead catalyst composition and loading, and catalyzation procedures on the performance of the chromium electrode were investigated. Three alternative catalyst systems were also examined, and 1/3 square foot size electrodes were fabricated and delivered to NASA at the conclusion of the program

Extracorporeal liver support devices in the ICU

Liver failure is common and carries high morbidity and mortality. Liver transplantation (LT) is the only definitive treatment available performed as an emergency in acute liver failure and electively for chronic liver disease. In the last 50 years, a number of extracorporeal liver support devices and modifications have emerged , some of them purely mechanical in nature aimed at detoxification, while others are cell based systems possessing bio-transformational capability. Mechanical devices are mainly based on albumin dialysis, albumin being a key transporter protein that is severely deficient and irreversibly destroyed in liver diseases. Despite a sound scientific rationale and good safety profile, none of the currently available devices have shown enough promise to be incorporated in routine clinical practice, their use being limited to specific clinical situations. This chapter describes currently available devices, their operational characteristics, current evidence of their utility and limitation, and the future developments in the field of extracorporeal liver support

Acute liver failure: updates in pathogenesis and management

Acute liver failure is a life-threatening illness precipitated by an acute liver injury in patients with no pre-existing liver disease. Acute viral hepatitis and drug-induced liver injury account for most cases, the clinical course characterized by the development of coagulopathy and hepatic encephalopathy, often progressing to multi-organ disease, which is associated with high fatality rates. The outcomes have improved significantly over time with improving standards of organ system support and access to liver transplantation for very sick individuals. The King's College criteria are the most commonly used tool for determination of prognosis and consideration for transplantation. Prompt diagnosis, immediate initiation of supportive care and aetiology-specific treatment, where applicable, as well as early discussions and transfer to a transplant centre, are the keys to successful outcome

Giant lipoma: an unusual cause of carpal tunnel syndrome

Carpal tunnel syndrome, in its idiopathic form, is an extremely common entrapment neuropathy in the clinical practice however secondary compressive causes are rare. Among secondary causes, tumors are even rarer. Although lipomas are the most common soft tissue tumor in the body, <5% of the benign tumors of the hand are lipomas. A 48-year old manual laborer man presented to us with a two-year history of numbness, tingling and burning pain in the palmar surface of the left hand and fingers along with a progressively increasing swelling in the hand and wrist. His medical history was unremarkable and no trauma episode was reported. According to the clinical examination and the result of median nerve conduction study (NCS) the diagnosis of carpal tunnel syndrome was established. Operative release of the transverse carpal ligament was subsequently performed along with excision of the lipoma using extensile open approach. Intraoperatively, median nerve and its digital branches were found to be stretched over the giant lipoma causing substantial compression to median nerve. Histopathological findings of the resected mass were consistent with lipoma. After two years the patient was pain-free without any sign of tumor recurrence. Lipomas are infrequently seen in hand and wrist, however giant lipoma as a cause of secondary carpal tunnel syndrome is even more rare, which makes this case interesting.Key words: Lipoma, carpal tunnel syndrome, median nerve, nerve compressio

Spectral analysis of Gene co-expression network of Zebrafish

We analyze the gene expression data of Zebrafish under the combined framework of complex networks and random matrix theory. The nearest neighbor spacing distribution of the corresponding matrix spectra follows random matrix predictions of Gaussian orthogonal statistics. Based on the eigenvector analysis we can divide the spectra into two parts, first part for which the eigenvector localization properties match with the random matrix theory predictions, and the second part for which they show deviation from the theory and hence are useful to understand the system dependent properties. Spectra with the localized eigenvectors can be characterized into three groups based on the eigenvalues. We explore the position of localized nodes from these different categories. Using an overlap measure, we find that the top contributing nodes in the different groups carry distinguished structural features. Furthermore, the top contributing nodes of the different localized eigenvectors corresponding to the lower eigenvalue regime form different densely connected structure well separated from each other. Preliminary biological interpretation of the genes, associated with the top contributing nodes in the localized eigenvectors, suggests that the genes corresponding to same vector share common features.Comment: 6 pages, four figures (accepted in EPL

Random matrix analysis of complex networks

We study complex networks under random matrix theory (RMT) framework. Using nearest-neighbor and next-nearest-neighbor spacing distributions we analyze the eigenvalues of adjacency matrix of various model networks, namely, random, scale-free and small-world networks. These distributions follow Gaussian orthogonal ensemble statistic of RMT. To probe long-range correlations in the eigenvalues we study spectral rigidity via $\Delta_3$ statistic of RMT as well. It follows RMT prediction of linear behavior in semi-logarithmic scale with slope being $\sim 1/\pi^2$. Random and scale-free networks follow RMT prediction for very large scale. Small-world network follows it for sufficiently large scale, but much less than the random and scale-free networks.Comment: accepted in Phys. Rev. E (replaced with the final version

Rapid Pathogen Detection for Infected Ascites in Cirrhosis using Metagenome Next-Generation Sequencing: A Case Series

Empirical antibiotic therapy in patients with spontaneous bacterial peritonitis (SBP) is common as pathogen(s) are identified in only 5%-20% patients using conventional culture-based techniques. Metagenome next-generation sequencing (mNGS) test is a promising approach for diagnosis of infectious disease. The clinical application of mNGS for infected ascites in cirrhotic patients is rarely reported. Here, we describe three cases to preliminarily explore the potential role of mNGS for microbiological diagnosis of ascites infection in exploratory manner. The clinical performance of ascites mNGS in cirrhotic patients remains to be further evaluated

Modification in CSF specific gravity in acutely decompensated cirrhosis and acute on chronic liver failure independent of encephalopathy, evidences for an early blood-CSF barrier dysfunction in cirrhosis

Although hepatic encephalopathy (HE) on the background of acute on chronic liver failure (ACLF) is associated with high mortality rates, it is unknown whether this is due to increased blood-brain barrier permeability. Specific gravity of cerebrospinal fluid measured by CT is able to estimate blood-cerebrospinal fluid-barrier permeability. This study aimed to assess cerebrospinal fluid specific gravity in acutely decompensated cirrhosis and to compare it in patients with or without ACLF and with or without hepatic encephalopathy. We identified all the patients admitted for acute decompensation of cirrhosis who underwent a brain CT-scan. Those patients could present acute decompensation with or without ACLF. The presence of hepatic encephalopathy was noted. They were compared to a group of stable cirrhotic patients and healthy controls. Quantitative brain CT analysis used the Brainview software that gives the weight, the volume and the specific gravity of each determined brain regions. Results are given as median and interquartile ranges and as relative variation compared to the control/baseline group. 36 patients presented an acute decompensation of cirrhosis. Among them, 25 presented with ACLF and 11 without ACLF; 20 presented with hepatic encephalopathy grade ≥ 2. They were compared to 31 stable cirrhosis patients and 61 healthy controls. Cirrhotic patients had increased cerebrospinal fluid specific gravity (CSF-SG) compared to healthy controls (+0.4 %, p < 0.0001). Cirrhotic patients with ACLF have decreased CSF-SG as compared to cirrhotic patients without ACLF (−0.2 %, p = 0.0030) that remained higher than in healthy controls. The presence of hepatic encephalopathy did not modify CSF-SG (−0.09 %, p = 0.1757). Specific gravity did not differ between different brain regions according to the presence or absence of either ACLF or HE. In patients with acute decompensation of cirrhosis, and those with ACLF, CSF specific gravity is modified compared to both stable cirrhotic patients and healthy controls. This pattern is observed even in the absence of hepatic encephalopathy suggesting that blood-CSF barrier impairment is manifest even in absence of overt hepatic encephalopathy