96 research outputs found

    Isolation and characterization of a chitinase-secreting mutant of mortierella pusilla with altered interaction with the mycoparasite piptocephalis virginiana

    Get PDF
    Mortierella pusilla is a susceptible host and supports good growth of the mycoparasite, Piptocephalis virginiana. Uninucleate spores of M. pusilla were sUbjected to N-methyl-N'-nitro-nitrosoguanidine (MNNG). To attain a high mutation frequency , a 1o-minute exposure to 10 mg/ml MNNG was used and lead to the survival of about 10 % of the spores. The exposed spores then were plated on chitin or milk plates. Approximately 30,000 colonies were examined after mutagenesis on the screening media. A strain, MUT23 , with abnormal slow growth morphology was found to delay parasitism by £. virginiana. The particular morphology was not due to auxotrophy, because this strain displayed normal hyphae when glucose was used as the sole carbon source. One interesting phenomenon was that MUT23 showed an extensive clearing zone around the colony on colloidal chitin agar after 20-25 d. On the same conditions, wild type strain did not show this phenotype. In addition, the MUT23 strain produced the same normal hypha as the wild type strain when it was grown on colloidal chitin agar. The MUT23 was also able to produce more spores on colloidal chitin agar than on malt-yeast extract and minimal media. The parasite germ tubes formed appressoria at the point of contact on the cell surface of wild type and MUT23 grown for 6 days cell surface but not on the cel surface of MUT23 grown for 2 days. Thus, interaction between MUT23 strain and the mycoparasite was dependent on MUT23 age. The effect of MUT23 filtrate on germination of the parasite was tested. Lysis of germinated spores of the parasite were observed in concentrated MUT23 filtered solution. MUT23 was compared to the wild type strain for their chitinase production in sUbmerged culture. The chitinase isozymes of both wild type and MUT23 were shown by immunoblotting. Eight distinct chitinase molecules were detected. MUT23 showed markedly higher chitinase activity than the wild type cultured in chitin-containing medium. Maximum chitinase activities of MUT23 were 13.5 fold higher at 20 day of the culture then that of wild type

    Att odla en destination.

    Get PDF

    Duloxetine hepatotoxicity: a case-series from the drug-induced liver injury network

    Full text link
    Aliment Pharmacol Ther 2010; 32: 1174–1183Case reports suggest that duloxetine hepatotoxicity may arise, but risk factors, presenting features and clinical course are not well-described.To describe the presenting features and outcomes of seven well-characterized patients with suspected duloxetine hepatotoxicity.Patients enrolled in the Drug-Induced Liver Injury Network Prospective Study underwent an extensive laboratory and clinical evaluation to exclude competing aetiologies of liver injury as well as a standardized assessment for causality and disease severity.Between 1/2006 and 9/2009, six of the seven cases of DILI attributed to duloxetine were assessed as definite or very likely. Median patient age was 49 years, six (86%) were women and the median latency from drug initiation to DILI onset was 50 days. Six patients developed jaundice and the median peak alanine aminotransferase in the five patients with acute hepatocellular injury was 1633 IU/L. Ascites developed in one patient and acute renal dysfunction in two others (29%). All patients recovered without liver transplantation even though three had pre-existing chronic liver disease. Liver histology in four cases demonstrated varying patterns of liver injury.Duloxetine hepatotoxicity developed within 2 months of drug intake and led to clinically significant liver injury. A spectrum of laboratory, histological and extra-hepatic features were noted at presentation.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/79147/1/j.1365-2036.2010.04449.x.pd

    Development and Pilot of a Checklist for Management of Acute Liver Failure in the Intensive Care Unit

    Get PDF
    Introduction Acute liver failure (ALF) is an ideal condition for use of a checklist. Our aims were to develop a checklist for the management of ALF in the intensive care unit (ICU) and assess the usability of the checklist among multiple providers. Methods The initial checklist was developed from published guidelines and expert opinion. The checklist underwent pilot testing at 11 academic liver transplant centers in the US and Canada. An anonymous, written survey was used to assess the usability and quality of the checklist. Written comments were used to improve the checklist following the pilot testing period. Results We received 81 surveys involving the management of 116 patients during the pilot testing period. The overall quality of the checklist was judged to be above average to excellent by 94% of users. On a 5-point Likert scale, the majority of survey respondents agreed or agreed strongly with the following checklist characteristics: the checklist was easy to read (99% agreed/agreed strongly), easy to use (97%), items are categorized logically (98%), time to complete the checklist did not interfere with delivery of appropriate and safe patient care (94%) and was not excessively burdensome (92%), the checklist allowed the user the freedom to use his or her clinical judgment (80%), it is a useful tool in the management of acute liver failure (98%). Web-based and mobile apps were developed for use of the checklist at the point of care. Conclusion The checklist for the management of ALF in the ICU was shown in this pilot study to be easy to use, helpful and accepted by a wide variety of practitioners at multiple sites in the US and Canada

    Safety, tolerability, and pharmacokinetics of l‐ornithine phenylacetate in patients with acute liver injury/failure and hyperammonemia

    Full text link
    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/142428/1/hep29621.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/142428/2/hep29621-sup-0001-suppinfo1.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/142428/3/hep29621_am.pd

    Herbal product use by persons enrolled in the hepatitis C Antiviral Long-Term Treatment Against Cirrhosis (HALT-C) Trial

    Full text link
    Herbal products, used for centuries in Far Eastern countries, are gaining popularity in western countries. Surveys indicate that persons with chronic hepatitis C (CHC) often use herbals, especially silymarin (milk thistle extract), hoping to improve the modest response to antiviral therapy and reduce side effects. The Hepatitis C Antiviral Long-Term Treatment Against Cirrhosis (HALT-C) Trial, involving persons with advanced CHC, nonresponders to prior antiviral therapy but still willing to participate in long-term pegylated interferon treatment, offered the opportunity to examine the use and potential effects of silymarin. Among 1145 study participants, 56% had never taken herbals, 21% admitted past use, and 23% were using them at enrollment. Silymarin constituted 72% of 60 herbals used at enrollment. Among all participants, 67% had never used silymarin, 16% used it in the past, and 17% used it at baseline. Silymarin use varied widely among the 10 participating study centers; men were more frequent users than women, as were non-Hispanic whites than African Americans and Hispanics. Silymarin use correlated strongly with higher education. No beneficial effect of silymarin was found on serum alanine aminotransferase or hepatitis C virus (HCV) RNA levels. Univariate analysis showed significantly fewer liver-related symptoms and better quality-of-life parameters in users than nonusers, but after reanalysis adjusted for covariates of age, race, education, alcohol consumption, exercise, body mass index, and smoking, only fatigue, nausea, liver pain, anorexia, muscle and joint pain, and general health remained significantly better in silymarin users. In conclusion, silymarin users had similar alanine aminotransferase and HCV levels to those of nonusers but fewer symptoms and somewhat better quality-of-life indices. Because its use among these HALT-C participants was self-motivated and uncontrolled, however, only a well-designed prospective study can determine whether silymarin provides benefit to persons with chronic hepatitis C. (H EPATOLOGY 2008.)Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/58026/1/22044_ftp.pd

    The Natural History of Severe Acute Liver Injury.

    Get PDF
    OBJECTIVES: Acute liver failure (ALF) is classically defined by coagulopathy and hepatic encephalopathy (HE); however, acute liver injury (ALI), i.e., severe acute hepatocyte necrosis without HE, has not been carefully defined nor studied. Our aim is to describe the clinical course of specifically defined ALI, including the risk and clinical predictors of poor outcomes, namely progression to ALF, the need for liver transplantation (LT) and death. METHODS: 386 subjects prospectively enrolled in the Acute Liver Failure Study Group registry between 1 September 2008 through 25 October 2013, met criteria for ALI: International Normalized Ratio (INR)≥2.0 and alanine aminotransferase (ALT)≥10 × elevated (irrespective of bilirubin level) for acetaminophen (N-acetyl-p-aminophenol, APAP) ALI, or INR≥2.0, ALT≥10x elevated, and bilirubin≥3.0 mg/dl for non-APAP ALI, both groups without any discernible HE. Subjects who progressed to poor outcomes (ALF, death, LT) were compared, by univariate analysis, with those who recovered. A model to predict poor outcome was developed using the random forest (RF) procedure. RESULTS: Progression to a poor outcome occurred in 90/386 (23%), primarily in non-APAP (71/179, 40%) vs. only 14/194 (7.2%) in APAP patients comprising 52% of all cases (13 cases did not have an etiology assigned; 5 of whom had a poor outcome). Of 82 variables entered into the RF procedure: etiology, bilirubin, INR, APAP level and duration of jaundice were the most predictive of progression to ALF, LT, or death. CONCLUSIONS: A majority of ALI cases are due to APAP, 93% of whom will improve rapidly and fully recover, while non-APAP patients have a far greater risk of poor outcome and should be targeted for early referral to a liver transplant center

    Human Amniotic Epithelial Cell Transplantation Induces Markers of Alternative Macrophage Activation and Reduces Established Hepatic Fibrosis

    Get PDF
    Chronic hepatic inflammation from multiple etiologies leads to a fibrogenic response that can progress to cirrhosis and liver failure. Transplantation of human amniotic epithelial cells (hAEC) from term delivered placenta has been shown to decrease mild to moderate hepatic fibrosis in a murine model. To model advanced human liver disease and assess the efficacy of hAEC therapy, we transplanted hAEC in mice with advanced hepatic fibrosis. Immunocompetent C57BL/6 mice were administered carbon tetrachloride (CCl4) twice weekly resulting in bridging fibrosis by 12 weeks. hAEC (2×106) were infused via the tail vein at week 8 or weeks 8 and 10 (single and double dose, respectively). Human cells were detected in mouse liver four weeks after transplantation showing hAEC engraftment. CCl4 treated mice receiving single or double hAEC doses showed a significant but similar decrease in liver fibrosis area associated with decreased activation of collagen-producing hepatic stellate cells and decreased hepatic protein levels of the pro-fibrogenic cytokine, transforming growth factor-beta1. CCl4 administration caused hepatic T cell infiltration that decreased significantly following hAEC transplantation. Hepatic macrophages play a crucial role in both fibrogenesis and fibrosis resolution. Mice exposed to CCl4 demonstrated increased numbers of hepatic macrophages compared to normal mice; the number of macrophages decreased significantly in CCl4 treated mice given hAEC. These mice had significantly lower hepatic protein levels of the chemokine monocyte chemoattractant protein-1 than mice given CCl4 alone. Alternatively activated M2 macrophages are associated with fibrosis resolution. CCl4 treated mice given hAEC showed increased expression of genes associated with M2 macrophages including YM-1, IL-10 and CD206. We provide novel data showing that hAEC transplantation induces a wound healing M2 macrophage phenotype associated with reduction of established hepatic fibrosis that justifies further investigation of this potential cell-based therapy for advanced hepatic fibrosis
    corecore