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Gerhard Kattner - One of the best experts on this subject based on the ideXlab platform.

  • fundamentals of molecular formula assignment to ultrahigh resolution mass data of natural organic matter
    Analytical Chemistry, 2007
    Co-Authors: Boris P Koch, Thorsten Dittmar, Matthias Witt, Gerhard Kattner
    Abstract:

    Ultrahigh-resolution mass spectrometry via the Fourier transform ion cyclotron resonance technique (FT-ICR-MS) allows the identification of thousands of different molecular formulas in natural organic matter and petroleum samples. Molecular formula assignment from mass data is most critical and time-consuming for these samples, and in many cases, several formulas can be determined for the same molecular mass. Therefore, automated procedures are required for an efficient exploitation of the extensive data sets. Here, we revise statements in a recent publication,1 which might result in a misleading impression about our approach of formula assignment in a previous work. We also summarize and categorize existing procedures for formula assignment. In addition, we propose new techniques, which are suitable to be implemented in automated evaluation software. The homologous series approach is extended toward a building block approach that can be applied as a new Exclusion Criterion for incorrect formula assignmen...

  • fundamentals of molecular formula assignment to ultrahigh resolution mass data of natural organic matter
    Analytical Chemistry, 2007
    Co-Authors: Boris P Koch, Thorsten Dittmar, Matthias Witt, Gerhard Kattner
    Abstract:

    Ultrahigh-resolution mass spectrometry via the Fourier transform ion cyclotron resonance technique (FT-ICR-MS) allows the identification of thousands of different molecular formulas in natural organic matter and petroleum samples. Molecular formula assignment from mass data is most critical and time-consuming for these samples, and in many cases, several formulas can be determined for the same molecular mass. Therefore, automated procedures are required for an efficient exploitation of the extensive data sets. Here, we revise statements in a recent publication,1 which might result in a misleading impression about our approach of formula assignment in a previous work. We also summarize and categorize existing procedures for formula assignment. In addition, we propose new techniques, which are suitable to be implemented in automated evaluation software. The homologous series approach is extended toward a building block approach that can be applied as a new Exclusion Criterion for incorrect formula assignments. The examination of stable isotope ratios of individual molecules in natural organic matter can be applied as an additional and intrinsic evaluation for calculated molecular formulas.

John P Roberts - One of the best experts on this subject based on the ideXlab platform.

  • alpha fetoprotein level 1000 ng ml as an Exclusion Criterion for liver transplantation in patients with hepatocellular carcinoma meeting the milan criteria
    Liver Transplantation, 2014
    Co-Authors: Bilal Hameed, Neil Mehta, Gonzalo Sapisochin, John P Roberts
    Abstract:

    Serum alpha-fetoprotein (AFP) has been increasingly recognized as a marker for a poor prognosis after liver transplantation (LT) for hepatocellular carcinoma (HCC). Many published reports, however, have included a large proportion of patients with HCC beyond the Milan criteria, and the effects of incorporating AFP as an Exclusion Criterion for LT remain unclear. We studied 211 consecutive patients undergoing LT for HCC within the Milan criteria according to imaging under the Model for End-Stage Liver Disease organ allocation system between June 2002 and January 2009. The majority (93.4%) had locoregional therapy before LT. The median follow-up was 4.5 years (minimum = 2 years). The Kaplan-Meier 1- and 5-year patient survival rates were 94.3% and 83.4%, respectively. In a univariate analysis, significant predictors of HCC recurrence included vascular invasion [hazard ratio (HR) = 10, 95% confidence interval (CI) = 3.9-26, P   1000 ng/mL (HR = 4.5, 95% CI = 1.3-15.3, P = 0.02), and an AFP level > 500 ng/mL (HR = 3.1, 95% CI = 1.04-9.4, P = 0.04). In a multivariate analysis, vascular invasion was the only significant predictor of tumor recurrence (HR = 5.6, 95% CI = 1.9-19, P = 0.02). An AFP level > 1000 ng/mL was the strongest pretransplant variable predicting vascular invasion (odds ratio = 6.8, 95% CI = 1.6-19.1, P = 0.006). The 1- and 5-year rates of survival without recurrence were 90% and 52.7%, respectively, for patients with an AFP level > 1000 ng/mL and 95% and 80.3%, respectively, for patients with an AFP level ≤ 1000 ng/mL (P = 0.026). Applying an AFP level > 1000 ng/mL as a cutoff would have resulted in the Exclusion of 4.7% of the patients from LT and a 20% reduction in HCC recurrence. In conclusion, an AFP level > 1000 ng/mL may be a surrogate for vascular invasion and may be used to predict posttransplant HCC recurrence. Incorporating an AFP level > 1000 ng/mL as an Exclusion Criterion for LT within the Milan criteria may further improve posttransplant outcomes. Liver Transpl 20:945-951, 2014. © 2014 AASLD.

  • alpha fetoprotein level 1000 ng ml as an Exclusion Criterion for liver transplantation in patients with hepatocellular carcinoma meeting the milan criteria
    Liver Transplantation, 2014
    Co-Authors: Bilal Hameed, Neil Mehta, Gonzalo Sapisochin, John P Roberts, Francis Y Yao
    Abstract:

    Serum alpha-fetoprotein (AFP) has been increasingly recognized as a marker for a poor prognosis after liver transplantation (LT) for hepatocellular carcinoma (HCC). Many published reports, however, have included a large proportion of patients with HCC beyond the Milan criteria, and the effects of incorporating AFP as an Exclusion Criterion for LT remain unclear. We studied 211 consecutive patients undergoing LT for HCC within the Milan criteria according to imaging under the Model for End-Stage Liver Disease organ allocation system between June 2002 and January 2009. The majority (93.4%) had locoregional therapy before LT. The median follow-up was 4.5 years (minimum = 2 years). The Kaplan-Meier 1- and 5-year patient survival rates were 94.3% and 83.4%, respectively. In a univariate analysis, significant predictors of HCC recurrence included vascular invasion [hazard ratio (HR) = 10, 95% confidence interval (CI) = 3.9-26, P 1000 ng/mL (HR = 4.5, 95% CI = 1.3-15.3, P = 0.02), and an AFP level > 500 ng/mL (HR = 3.1, 95% CI = 1.04-9.4, P = 0.04). In a multivariate analysis, vascular invasion was the only significant predictor of tumor recurrence (HR = 5.6, 95% CI = 1.9-19, P = 0.02). An AFP level > 1000 ng/mL was the strongest pretransplant variable predicting vascular invasion (odds ratio = 6.8, 95% CI = 1.6-19.1, P = 0.006). The 1- and 5-year rates of survival without recurrence were 90% and 52.7%, respectively, for patients with an AFP level > 1000 ng/mL and 95% and 80.3%, respectively, for patients with an AFP level ≤ 1000 ng/mL (P = 0.026). Applying an AFP level > 1000 ng/mL as a cutoff would have resulted in the Exclusion of 4.7% of the patients fr m LT and a 20% reduction in HCC recurrence. In conclusion, an AFP level > 1000 ng/mL may be a surrogate for vascular invasion and may be used to predict posttransplant HCC recurrence. Incorporating an AFP level > 1000 ng/mL as an Exclusion Criterion for LT within the Milan criteria may further improve posttransplant outcomes.

Gonzalo Sapisochin - One of the best experts on this subject based on the ideXlab platform.

  • alpha fetoprotein level 1000 ng ml as an Exclusion Criterion for liver transplantation in patients with hepatocellular carcinoma meeting the milan criteria
    Liver Transplantation, 2014
    Co-Authors: Bilal Hameed, Neil Mehta, Gonzalo Sapisochin, John P Roberts
    Abstract:

    Serum alpha-fetoprotein (AFP) has been increasingly recognized as a marker for a poor prognosis after liver transplantation (LT) for hepatocellular carcinoma (HCC). Many published reports, however, have included a large proportion of patients with HCC beyond the Milan criteria, and the effects of incorporating AFP as an Exclusion Criterion for LT remain unclear. We studied 211 consecutive patients undergoing LT for HCC within the Milan criteria according to imaging under the Model for End-Stage Liver Disease organ allocation system between June 2002 and January 2009. The majority (93.4%) had locoregional therapy before LT. The median follow-up was 4.5 years (minimum = 2 years). The Kaplan-Meier 1- and 5-year patient survival rates were 94.3% and 83.4%, respectively. In a univariate analysis, significant predictors of HCC recurrence included vascular invasion [hazard ratio (HR) = 10, 95% confidence interval (CI) = 3.9-26, P   1000 ng/mL (HR = 4.5, 95% CI = 1.3-15.3, P = 0.02), and an AFP level > 500 ng/mL (HR = 3.1, 95% CI = 1.04-9.4, P = 0.04). In a multivariate analysis, vascular invasion was the only significant predictor of tumor recurrence (HR = 5.6, 95% CI = 1.9-19, P = 0.02). An AFP level > 1000 ng/mL was the strongest pretransplant variable predicting vascular invasion (odds ratio = 6.8, 95% CI = 1.6-19.1, P = 0.006). The 1- and 5-year rates of survival without recurrence were 90% and 52.7%, respectively, for patients with an AFP level > 1000 ng/mL and 95% and 80.3%, respectively, for patients with an AFP level ≤ 1000 ng/mL (P = 0.026). Applying an AFP level > 1000 ng/mL as a cutoff would have resulted in the Exclusion of 4.7% of the patients from LT and a 20% reduction in HCC recurrence. In conclusion, an AFP level > 1000 ng/mL may be a surrogate for vascular invasion and may be used to predict posttransplant HCC recurrence. Incorporating an AFP level > 1000 ng/mL as an Exclusion Criterion for LT within the Milan criteria may further improve posttransplant outcomes. Liver Transpl 20:945-951, 2014. © 2014 AASLD.

  • alpha fetoprotein level 1000 ng ml as an Exclusion Criterion for liver transplantation in patients with hepatocellular carcinoma meeting the milan criteria
    Liver Transplantation, 2014
    Co-Authors: Bilal Hameed, Neil Mehta, Gonzalo Sapisochin, John P Roberts, Francis Y Yao
    Abstract:

    Serum alpha-fetoprotein (AFP) has been increasingly recognized as a marker for a poor prognosis after liver transplantation (LT) for hepatocellular carcinoma (HCC). Many published reports, however, have included a large proportion of patients with HCC beyond the Milan criteria, and the effects of incorporating AFP as an Exclusion Criterion for LT remain unclear. We studied 211 consecutive patients undergoing LT for HCC within the Milan criteria according to imaging under the Model for End-Stage Liver Disease organ allocation system between June 2002 and January 2009. The majority (93.4%) had locoregional therapy before LT. The median follow-up was 4.5 years (minimum = 2 years). The Kaplan-Meier 1- and 5-year patient survival rates were 94.3% and 83.4%, respectively. In a univariate analysis, significant predictors of HCC recurrence included vascular invasion [hazard ratio (HR) = 10, 95% confidence interval (CI) = 3.9-26, P 1000 ng/mL (HR = 4.5, 95% CI = 1.3-15.3, P = 0.02), and an AFP level > 500 ng/mL (HR = 3.1, 95% CI = 1.04-9.4, P = 0.04). In a multivariate analysis, vascular invasion was the only significant predictor of tumor recurrence (HR = 5.6, 95% CI = 1.9-19, P = 0.02). An AFP level > 1000 ng/mL was the strongest pretransplant variable predicting vascular invasion (odds ratio = 6.8, 95% CI = 1.6-19.1, P = 0.006). The 1- and 5-year rates of survival without recurrence were 90% and 52.7%, respectively, for patients with an AFP level > 1000 ng/mL and 95% and 80.3%, respectively, for patients with an AFP level ≤ 1000 ng/mL (P = 0.026). Applying an AFP level > 1000 ng/mL as a cutoff would have resulted in the Exclusion of 4.7% of the patients fr m LT and a 20% reduction in HCC recurrence. In conclusion, an AFP level > 1000 ng/mL may be a surrogate for vascular invasion and may be used to predict posttransplant HCC recurrence. Incorporating an AFP level > 1000 ng/mL as an Exclusion Criterion for LT within the Milan criteria may further improve posttransplant outcomes.

Bilal Hameed - One of the best experts on this subject based on the ideXlab platform.

  • alpha fetoprotein level 1000 ng ml as an Exclusion Criterion for liver transplantation in patients with hepatocellular carcinoma meeting the milan criteria
    Liver Transplantation, 2014
    Co-Authors: Bilal Hameed, Neil Mehta, Gonzalo Sapisochin, John P Roberts
    Abstract:

    Serum alpha-fetoprotein (AFP) has been increasingly recognized as a marker for a poor prognosis after liver transplantation (LT) for hepatocellular carcinoma (HCC). Many published reports, however, have included a large proportion of patients with HCC beyond the Milan criteria, and the effects of incorporating AFP as an Exclusion Criterion for LT remain unclear. We studied 211 consecutive patients undergoing LT for HCC within the Milan criteria according to imaging under the Model for End-Stage Liver Disease organ allocation system between June 2002 and January 2009. The majority (93.4%) had locoregional therapy before LT. The median follow-up was 4.5 years (minimum = 2 years). The Kaplan-Meier 1- and 5-year patient survival rates were 94.3% and 83.4%, respectively. In a univariate analysis, significant predictors of HCC recurrence included vascular invasion [hazard ratio (HR) = 10, 95% confidence interval (CI) = 3.9-26, P   1000 ng/mL (HR = 4.5, 95% CI = 1.3-15.3, P = 0.02), and an AFP level > 500 ng/mL (HR = 3.1, 95% CI = 1.04-9.4, P = 0.04). In a multivariate analysis, vascular invasion was the only significant predictor of tumor recurrence (HR = 5.6, 95% CI = 1.9-19, P = 0.02). An AFP level > 1000 ng/mL was the strongest pretransplant variable predicting vascular invasion (odds ratio = 6.8, 95% CI = 1.6-19.1, P = 0.006). The 1- and 5-year rates of survival without recurrence were 90% and 52.7%, respectively, for patients with an AFP level > 1000 ng/mL and 95% and 80.3%, respectively, for patients with an AFP level ≤ 1000 ng/mL (P = 0.026). Applying an AFP level > 1000 ng/mL as a cutoff would have resulted in the Exclusion of 4.7% of the patients from LT and a 20% reduction in HCC recurrence. In conclusion, an AFP level > 1000 ng/mL may be a surrogate for vascular invasion and may be used to predict posttransplant HCC recurrence. Incorporating an AFP level > 1000 ng/mL as an Exclusion Criterion for LT within the Milan criteria may further improve posttransplant outcomes. Liver Transpl 20:945-951, 2014. © 2014 AASLD.

  • alpha fetoprotein level 1000 ng ml as an Exclusion Criterion for liver transplantation in patients with hepatocellular carcinoma meeting the milan criteria
    Liver Transplantation, 2014
    Co-Authors: Bilal Hameed, Neil Mehta, Gonzalo Sapisochin, John P Roberts, Francis Y Yao
    Abstract:

    Serum alpha-fetoprotein (AFP) has been increasingly recognized as a marker for a poor prognosis after liver transplantation (LT) for hepatocellular carcinoma (HCC). Many published reports, however, have included a large proportion of patients with HCC beyond the Milan criteria, and the effects of incorporating AFP as an Exclusion Criterion for LT remain unclear. We studied 211 consecutive patients undergoing LT for HCC within the Milan criteria according to imaging under the Model for End-Stage Liver Disease organ allocation system between June 2002 and January 2009. The majority (93.4%) had locoregional therapy before LT. The median follow-up was 4.5 years (minimum = 2 years). The Kaplan-Meier 1- and 5-year patient survival rates were 94.3% and 83.4%, respectively. In a univariate analysis, significant predictors of HCC recurrence included vascular invasion [hazard ratio (HR) = 10, 95% confidence interval (CI) = 3.9-26, P 1000 ng/mL (HR = 4.5, 95% CI = 1.3-15.3, P = 0.02), and an AFP level > 500 ng/mL (HR = 3.1, 95% CI = 1.04-9.4, P = 0.04). In a multivariate analysis, vascular invasion was the only significant predictor of tumor recurrence (HR = 5.6, 95% CI = 1.9-19, P = 0.02). An AFP level > 1000 ng/mL was the strongest pretransplant variable predicting vascular invasion (odds ratio = 6.8, 95% CI = 1.6-19.1, P = 0.006). The 1- and 5-year rates of survival without recurrence were 90% and 52.7%, respectively, for patients with an AFP level > 1000 ng/mL and 95% and 80.3%, respectively, for patients with an AFP level ≤ 1000 ng/mL (P = 0.026). Applying an AFP level > 1000 ng/mL as a cutoff would have resulted in the Exclusion of 4.7% of the patients fr m LT and a 20% reduction in HCC recurrence. In conclusion, an AFP level > 1000 ng/mL may be a surrogate for vascular invasion and may be used to predict posttransplant HCC recurrence. Incorporating an AFP level > 1000 ng/mL as an Exclusion Criterion for LT within the Milan criteria may further improve posttransplant outcomes.

Giovanni Liguori - One of the best experts on this subject based on the ideXlab platform.

  • an observational cohort study investigating the incidence rate of infectious complications after routine office nephrostomy tube replacement without using antimicrobial prophylaxis
    Urology, 2020
    Co-Authors: Michele Rizzo, Luca Ongaro, Francesco Claps, Paolo Umari, Stefano Bucci, Carlo Trombetta, Tony T Cai, Giovanni Liguori
    Abstract:

    OBJECTIVE To investigate the incidence of infectious complications after routine office nephrostomy tube replacement (NTR) in patients that did not receive antimicrobial prophylaxis (AMP). METHODS We prospectively enrolled all patients undergoing routine office NTR between July 2018 and September 2019. Each procedure was considered an independent event. Clinical, microbiological, demographic data were collected. AMP was Exclusion Criterion. All patients received a questionnaire via phone call within 3 weeks after NTR investigating fever, antibiotics use, hospital admissions. Infectious complications risk was assessed with univariate and multivariate binomial logistic regression analysis. RESULTS One hundred forty-five routine NTRs were performed. Nineteen patients receiving AMP were excluded. Median age was 78 years (interquartile range 71-81). Charlson Comorbidity Index (CCI) score was ≥5 in 53.2% of patients, 34 had positive urine culture, none received AMP. Seventeen (13.49%) patients reported fever after procedure, 9 received antibiotic therapy while fever resolved spontaneously in 8. Three patients needed hospitalization, 2 for nephrostomy malfunction, 1 for infectious complications. At multivariate analysis only CCI score ≥3 was associated (P < .001) with increased infectious complications risk. CONCLUSION In this study fever occurs after the 13.5% of the routine NTRs, in almost half cases resolves spontaneously rather than with oral antimicrobial therapy. Avoiding AMP before routine NTR does not expose patients to life-threatening infections.