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Pembrolizumab in combination with gemcitabine for patients with HER2-negative advanced breast cancer: GEICAM/2015-04 (PANGEA-Breast) study. BMC Cancer 2022; 22:1258. [PMID: 36463104 PMCID: PMC9719636 DOI: 10.1186/s12885-022-10363-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Accepted: 11/24/2022] [Indexed: 12/04/2022] Open
Abstract
BACKGROUND We evaluated a new chemoimmunotherapy combination based on the anti-PD1 monoclonal antibody pembrolizumab and the pyrimidine antimetabolite gemcitabine in HER2- advanced breast cancer (ABC) patients previously treated in the advanced setting, in order to explore a potential synergism that could eventually obtain long term benefit in these patients. METHODS HER2-negative ABC patients received 21-day cycles of pembrolizumab 200 mg (day 1) and gemcitabine (days 1 and 8). A run-in-phase (6 + 6 design) was planned with two dose levels (DL) of gemcitabine (1,250 mg/m2 [DL0]; 1,000 mg/m2 [DL1]) to determine the recommended phase II dose (RP2D). The primary objective was objective response rate (ORR). Tumor infiltrating lymphocytes (TILs) density and PD-L1 expression in tumors and myeloid-derived suppressor cells (MDSCs) levels in peripheral blood were analyzed. RESULTS Fourteen patients were treated with DL0, resulting in RP2D. Thirty-six patients were evaluated during the first stage of Simon's design. Recruitment was stopped as statistical assumptions were not met. The median age was 52; 21 (58%) patients had triple-negative disease, 28 (78%) visceral involvement, and 27 (75%) ≥ 2 metastatic locations. Progression disease was observed in 29 patients. ORR was 15% (95% CI, 5-32). Eight patients were treated ≥ 6 months before progression. Fourteen patients reported grade ≥ 3 treatment-related adverse events. Due to the small sample size, we did not find any clear association between immune tumor biomarkers and treatment efficacy that could identify a subgroup with higher probability of response or better survival. However, patients that experienced a clinical benefit showed decreased MDSCs levels in peripheral blood along the treatment. CONCLUSION Pembrolizumab 200 mg and gemcitabine 1,250 mg/m2 were considered as RP2D. The objective of ORR was not met; however, 22% patients were on treatment for ≥ 6 months. ABC patients that could benefit of chemoimmunotherapy strategies must be carefully selected by robust and validated biomarkers. In our heavily pretreated population, TILs, PD-L1 expression and MDSCs levels could not identify a subgroup of patients for whom the combination of gemcitabine and pembrolizumab would induce long term benefit. TRIAL REGISTRATION ClinicalTrials.gov and EudraCT (NCT03025880 and 2016-001,779-54, respectively). Registration dates: 20/01/2017 and 18/11/2016, respectively.
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Biological Deacidification Strategies for White Wines. S AFR J ENOL VITIC 2021. [DOI: 10.21548/42-2-4474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Traditionally, the use of malolactic fermentation gives rise to microbiologically stable wines. However, malolactic fermentation is not free from possible collateral effects that can take place under specific scenarios. The present work tests the influence of different biological deacidification strategies on the volatile and non-volatile components of white must from Germany. The study compared mixed cultures of Lachancea thermotolerans and Schizosaccharomyces pombe and a pure culture of Sc. pombe to the classical biological deacidification process performed by lactic acid bacteria. Strains of Oenococcus oeni and Lactiplantibacillus plantarum were co- or sequentially inoculated with S. cerevisiae to carry out malolactic fermentation. Different fermentation treatments took place at a laboratory scale of 0.6 L in vessels of 0.75 L. The instrumental techniques Fourier-transform mid-infrared spectroscopy (FT-MIR), high performance liquid chromatography (HPLC) and gas chromatography–mass spectrometry (GC-MS) were used to evaluate different chemical parameters in the final wines. The results showed the ability of Sc. pombe to consume malic acid in combination with L. thermotolerans without using S. cerevisiae or lactic acid bacteria. Fermentations involving Sc. pombe consumed all the malic acid, although they reduced the concentrations of higher alcohols, fatty acids and acetic acid. Simultaneous alcoholic and malolactic fermentations reduced malic acid by about 80%, while classical malolactic fermentation reduced it by 100%. Fermentations involving L. thermotolerans produced the highest lactic acid, ester and glycerol concentrations.
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Results from a Phase II Trial of Pembrolizumab (P) Plus Gemcitabine (GEM) in patients (PTS) with HER2-Negative Advanced Breast Cancer (ABC): GEICAM/2015-04 (PANGEA-Breast) study. Ann Oncol 2019. [DOI: 10.1093/annonc/mdz451.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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LC-QQQ-MS routine analysis method for new biomarker quantification in plasma aimed at early chronic kidney disease diagnosis. J Pharm Biomed Anal 2019; 169:82-89. [DOI: 10.1016/j.jpba.2019.02.042] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 02/25/2019] [Accepted: 02/26/2019] [Indexed: 12/28/2022]
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5
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Run-in-phase results from a multicenter phase II trial to evaluate pembrolizumab (P) and gemcitabine (Gem) in patients (pts) with HER2-negative advanced breast cancer (ABC): GEICAM/2015-04 PANGEA-Breast. Ann Oncol 2018. [DOI: 10.1093/annonc/mdy487.019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Evaluation of the effect of polymorphism on G-quadruplex-ligand interaction by means of spectroscopic and chromatographic techniques. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2018; 196:185-195. [PMID: 29448171 DOI: 10.1016/j.saa.2018.02.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Revised: 01/16/2018] [Accepted: 02/04/2018] [Indexed: 06/08/2023]
Abstract
Guanine-rich sequences may fold into highly ordered structures known as G-quadruplexes. Apart from the monomeric G-quadruplex, these sequences may form multimeric structures that are not usually considered when studying interaction with ligands. This work studies the interaction of a ligand, crystal violet, with three guanine-rich DNA sequences with the capacity to form multimeric structures. These sequences correspond to short stretches found near the promoter regions of c-kit and SMARCA4 genes. Instrumental techniques (circular dichroism, molecular fluorescence, size-exclusion chromatography and electrospray ionization mass spectrometry) and multivariate data analysis were used for this purpose. The polymorphism of G-quadruplexes was characterized prior to the interaction studies. The ligand was shown to interact preferentially with the monomeric G-quadruplex; the binding stoichiometry was 1:1 and the binding constant was in the order of 105M-1 for all three sequences. The results highlight the importance of DNA treatment prior to interaction studies.
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Abstract OT1-01-02: A multicenter phase II trial to evaluate the efficacy and safety of pembrolizumab and gemcitabine in patients with HER2-negative advanced breast cancer: GEICAM/2015-04 PANGEA-Breast. Cancer Res 2018. [DOI: 10.1158/1538-7445.sabcs17-ot1-01-02] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: Treatment options for advanced breast cancer (ABC) are multiple but unable to properly respond to current clinical needs. In particular, improved therapies are needed for triple negative and hormone receptor (HR)-positive but heavily pretreated patients. Pembrolizumab (P) is a human monoclonal antibody that blocks the PD-1/PD-L1 interaction hence potentiates anticancer T cell responses. Gemcitabine (G) is a cytotoxic drug with well-known immunostimulatory properties. Here, we report an ongoing phase II clinical trial to identify the Recommended Phase II Dose (RP2D) and the efficacy of the combination of these two agents in ABC patients. We hypothesize that these agents may synergize to induce responses with long term clinical benefit (ClinicalTrials.gov Identifier: NCT03025880).
Trial Design:
Eligible patients are HER2-negative ABC patients who received prior treatment with anthracyclines and taxanes and two or more prior lines of hormone therapy, if HR-positive disease. Patients with CNS involvement are also eligible if clinically stable. Treatment consists of 21-day cycles with 200 mg P on day 1 and G on days 1 and 8. In the safety dose testing, we use a standard 6+6 design with 2 dose levels (DL) of G: 1250 mg/m2 (DL0) and 1000 mg/m2 (DL1). Patients are treated until radiologic or symptomatic progression, or unacceptable toxicity. The primary objectives are RP2D and objective response rate (ORR) of the combination; secondary objectives include evaluation of safety and tolerability and other efficacy variables (progression-free survival [PFS], clinical benefit rate [CBR], response duration [RD] and overall survival [OS]). Efficacy is measured by RECIST 1.1. and irRECIST. Safety is measured using the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI-CTCAE) 4.0. As exploratory objectives, immunological biomarkers are analyzed in tumor biopsies and blood samples and correlated with (1) clinical efficacy and (2) disease outcomes.Sequential tumor samples are collected at baseline, cycle 3 and at progression. Blood samples are drawn at baseline, cycle 3, and cycle 6, or at post-treatment visit (whatever occurs first). Tumor samples are characterized for intratumoral and stromal tumor-infiltrating lymphocytes, tumor-associated macrophages and myeloid-derived suppressor cells, PD-L1 expression in tumor cells and stroma. Moreover, molecular and genetic profiling will be performed. Blood samples are characterized for peripheral blood mononuclear cell (PBMC) phenotype (including expression of co-activatory and co-inhibitory receptors), cytokine profile, and activity of other immunosuppressive pathways (e.g., IDO1-dependent tryptophan catabolism). These results will be compared with data from a cohort of healthy volunteers.
A maximum of 65 patients will be included. The study is approved by the ethical committee and Competent Authority of Spain and already open for patient recruitment in 2 of the 10 participating sites.
Keywords:
Breast
HER2 negative
Pembrolizumab
Immunotherapy
Citation Format: de la Cruz L, Sánchez-Margalet V, Berraondo P, Benito S, Escudero MJ, Caballero R, Carrasco E, Galluzzi L, Rojo F. A multicenter phase II trial to evaluate the efficacy and safety of pembrolizumab and gemcitabine in patients with HER2-negative advanced breast cancer: GEICAM/2015-04 PANGEA-Breast [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr OT1-01-02.
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Abstract
Summary
Objectives:
The traditional techniques of data analysis are often not sufficient to characterize the complex dynamics of respiration. In this study the respiratory pattern variability was analyzed using symbolic dynamics.
Methods:
A group of 20 patients on weaning trials from mechanical ventilation were studied at two different pressure support ventilation levels. Breath duration (TTOT) time series and the relation TI/TTOT, that contains the influence of inspiratory time (TI), were considered. Length-3 words and 3 different symbols were proposed. The incidence of the overlapping τ and the parameter α were analyzed.
Results:
From the breath duration time series, the distribution of words with probability of occurrence higher than 6% was concentrated on one word for low respiratory variability, whereas high variability was characterized by 4 words, presenting a statistically significant difference (p ≤ 0.0005). The probability occurrence of words “110” and “111” was also significantly different (p ≤ .0005) when comparing both variabilities.
Conclusion:
The analysis carried out obtained discriminant functions able to correctly classify all the testing set series. These results permit the consideration of symbolic dynamics as a promising methodology to study the respiratory pattern variability.
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A helpful approach to organ donation: From end-of-life care to effective organ transplantation. Am J Transplant 2018; 18:528-529. [PMID: 28891206 DOI: 10.1111/ajt.14493] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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Untargeted metabolomics for plasma biomarker discovery for early chronic kidney disease diagnosis in pediatric patients using LC-QTOF-MS. Analyst 2018; 143:4448-4458. [DOI: 10.1039/c8an00864g] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Pediatric chronic kidney disease (CKD) is a clinical syndrome characterized by renal hypofunction occurring due to gradual and irreversible kidney damage that can further progress over time.
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Viability qPCR, a new tool for Legionella risk management. Int J Hyg Environ Health 2017; 220:1318-1324. [DOI: 10.1016/j.ijheh.2017.08.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Revised: 08/23/2017] [Accepted: 08/23/2017] [Indexed: 10/18/2022]
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Plasma biomarker discovery for early chronic kidney disease diagnosis based on chemometric approaches using LC-QTOF targeted metabolomics data. J Pharm Biomed Anal 2017; 149:46-56. [PMID: 29100030 DOI: 10.1016/j.jpba.2017.10.036] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Revised: 10/10/2017] [Accepted: 10/28/2017] [Indexed: 11/16/2022]
Abstract
Chronic kidney disease (CKD) is a progressive pathological condition in which renal function deteriorates in time. The first diagnosis of CKD is often carried out in general care attention by general practitioners by means of serum creatinine (CNN) levels. However, it lacks sensitivity and thus, there is a need for new robust biomarkers to allow the detection of kidney damage particularly in early stages. Multivariate data analysis of plasma concentrations obtained from LC-QTOF targeted metabolomics method may reveal metabolites suspicious of being either up-regulated or down-regulated from urea cycle, arginine methylation and arginine-creatine metabolic pathways in CKD pediatrics and controls. The results show that citrulline (CIT), symmetric dimethylarginine (SDMA) and S-adenosylmethionine (SAM) are interesting biomarkers to support diagnosis by CNN: early CKD samples and controls were classified with an increase in classification accuracy of 18% when using these 4 metabolites compared to CNN alone. These metabolites together allow classification of the samples into a definite stage of the disease with an accuracy of 74%, being the 90% of the misclassifications one level above or below the CKD stage set by the nephrologists. Finally, sex-related, age-related and treatment-related effects were studied, to evaluate whether changes in metabolite concentration could be attributable to these factors, and to correct them in case a new equation is developed with these potential biomarkers for the diagnosis and monitoring of pediatric CKD.
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A phase II trial of dasatinib (D) in combination with trastuzumab (T) and paclitaxel (P) in the first line treatment of HER2 positive metastatic breast cancer (MBC) patients (pts): GEICAM/2010-04. Ann Oncol 2017. [DOI: 10.1093/annonc/mdx365.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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14
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Brain-Dead Donors With Ornithine Transcarbamylase Deficiency: A Big Learning Opportunity in Clinical Evaluation. Am J Transplant 2017; 17:2229. [PMID: 28544377 DOI: 10.1111/ajt.14367] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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15
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Use of Schizosaccharomyces strains for wine fermentation—Effect on the wine composition and food safety. Int J Food Microbiol 2016; 232:63-72. [DOI: 10.1016/j.ijfoodmicro.2016.05.023] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 05/05/2016] [Accepted: 05/20/2016] [Indexed: 10/21/2022]
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16
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Presence ofListeria monocytogenesin Prepared Foods: Analysis of Influencing Factors. J FOOD PROCESS PRES 2016. [DOI: 10.1111/jfpp.12842] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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Abstract OT3-01-02: A phase I-II trial of dasatinib in combination with trastuzumab (T) and paclitaxel in the first line treatment of HER2 positive metastatic breast cancer (MBC) patients: GEICAM/2010-04. Cancer Res 2016. [DOI: 10.1158/1538-7445.sabcs15-ot3-01-02] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: Resistance to targeted-therapies is a current problem in our clinical practice. In HER2 overexpressing tumors, resistance to trastuzumab-based therapies is widely observed. Expression of SRC has been pre-clinically linked to trastuzumab resistance and the addition of the multi-tyrosine kinase inhibitor dasatinib to trastuzumab increases its antitumor activity (Seoane S, et al. J Natl Cancer Inst. 2010). On previous studies, Dasatinib showed a good toxicity profile, with low grade 3-4 toxicity rates (E. Mayer, et al. J Clin Oncol 2009). We have designed a phase I-II trial combining dasatinib with standard trastuzumab/paclitaxel. (ClinicalTrials.gov Identifier: NCT01306942). In this abstract we report the description of the phase II part of the trial which is ongoing.
Trial Design: Eligible patients must be HER2+ (evaluated by central laboratory and assessed by immunohistochemistry and fluorescent in-situ hybridization) MBC and candidates for trastuzumab + chemotherapy as first line treatment. Taxanes and trastuzumab administered in the adjuvant setting are permitted if given >12 months before the inclusion. Patients with CNS involvement are eligible if treated and clinically stable without medication. Treatment consists of trastuzumab 2 mg/kg weekly (following a loading dose of 4 mg/kg in cycle 1), weekly paclitaxel (80 mg/m2, 3 weeks on-one week off) and dasatinib 100 mg once daily (based on the recommended phase II dose from the phase I part, Gil-Martin M, et al. European Breast Cancer Conference 2014, P-041) in a 28-days cycle. Patients are treated until radiologic or symptomatic progression or unacceptable toxicity.
The primary objective for this phase II is efficacy, measured by Objective Response Rate (ORR according to RECIST 1.1). Secondary objectives are: Safety (evaluated using NCI-CTCAE v 4.03), Clinical Benefit Rate, Time to Progression, Progression Free Survival and Response Duration. Pharmacodynamic biomarkers include pAKT, pS6, pSRC, pErk1/2 in tumor tissue samples, mononuclear cells in blood samples and in skin tissue. An additional exploratory objective is to evaluate the correlation between the early presence of lymphocytosis and efficacy. The study will be considered positive if ORR increases 25% from a 50% ORR observed in previous studies with paclitaxel + trastuzumab. We need to include 28 evaluable patients to demonstrate this hypothesis (with an alpha error of 0.05 and a statistical power of 80%), assuming a 10% drop-out rate. Twenty one patients have already been included. Recruitment is expected to finish by the end of 2015.
Citation Format: Ocaña A, Ruiz Borrego M, Gil-Martín M, Antolín S, Guerrero Á, Vidal Boixader L, Martín M, Trigo Pérez JM, Rojo F, Jerez Y, Atienza M, Pernas S, Hernando A, Carrasco E, Benito S, Caballero R, Pandiella A. A phase I-II trial of dasatinib in combination with trastuzumab (T) and paclitaxel in the first line treatment of HER2 positive metastatic breast cancer (MBC) patients: GEICAM/2010-04. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr OT3-01-02.
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Classification of patients undergoing weaning from mechanical ventilation using the coherence between heart rate variability and respiratory flow signal. Physiol Meas 2015; 36:1439-52. [PMID: 26020593 DOI: 10.1088/0967-3334/36/7/1439] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Weaning from mechanical ventilation is still one of the most challenging problems in intensive care. Unnecessary delays in discontinuation and weaning trials that are undertaken too early are both undesirable. This study investigated the contribution of spectral signals of heart rate variability (HRV) and respiratory flow, and their coherence to classifying patients on weaning process from mechanical ventilation. A total of 121 candidates for weaning, undergoing spontaneous breathing tests, were analyzed: 73 were successfully weaned (GSucc), 33 failed to maintain spontaneous breathing so were reconnected (GFail), and 15 were extubated after the test but reintubated within 48 h (GRein). The power spectral density and magnitude squared coherence (MSC) of HRV and respiratory flow signals were estimated. Dimensionality reduction was performed using principal component analysis (PCA) and sequential floating feature selection. The patients were classified using a fuzzy K-nearest neighbour method. PCA of the MSC gave the best classification with the highest accuracy of 92% classifying GSucc versus GFail patients, and 86% classifying GSucc versus GRein patients. PCA of the respiratory flow signal gave the best classification between GFail and GRein patients (79% accuracy). These classifiers showed a good balance between sensitivity and specificity. Besides, the spectral coherence between HRV and the respiratory flow signal, in patients on weaning trial process, can contribute to the extubation decision.
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Selection of appropriate Schizosaccharomyces strains for winemaking. Food Microbiol 2014; 42:218-24. [DOI: 10.1016/j.fm.2014.03.014] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2013] [Revised: 02/15/2014] [Accepted: 03/18/2014] [Indexed: 10/25/2022]
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20
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FRI0545 Treatment with anti IL-1 and Infectious Complications in Paediatric Patients with Systemic Juvenile Idiophatic Arthritis and Autoinflammatoy Diseases. Ann Rheum Dis 2014. [DOI: 10.1136/annrheumdis-2014-eular.5866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Reduction of 4-ethylphenol production in red wines using HCDC+ yeasts and cinnamyl esterases. Enzyme Microb Technol 2012; 52:99-104. [PMID: 23273278 DOI: 10.1016/j.enzmictec.2012.11.001] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2012] [Revised: 10/05/2012] [Accepted: 11/01/2012] [Indexed: 10/27/2022]
Abstract
Hydroxycinnamate decarboxylase (HCDC) activity has been evaluated in several commercial yeast strains. The combined effect of using cinnamyl esterases (CE) and HCDC+ Saccharomyces cerevisiae strains has been studied in the formation of vinylphenolic pyranoanthocyanins (VPAs) during fermentation, analysing the kind and concentration of pigments formed according to the yeast strain used. Wines fermented with yeasts HCDC+ were contaminated with Dekkera bruxellensis and afterwards analysed to evaluate the formation of ethylphenols (EPs). The musts treated with CE and later fermented with HCDC+ yeast strains showed lower contents of 4-ethylphenol than those fermented with HCDC- strains. This reduction in the EP content is due to the transformation of hydroxycinnamic acids in stable VPAs pigments. The associated use of CEs and HCDC+ Saccharomyces strains is a natural strategy to reduce the formation of EPs in wines contaminated by Dekkera/Brettanomyces.
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Formation of pyranoanthocyanins by Schizosaccharomyces pombe during the fermentation of red must. Int J Food Microbiol 2012; 159:47-53. [PMID: 22921967 DOI: 10.1016/j.ijfoodmicro.2012.08.007] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2012] [Revised: 07/31/2012] [Accepted: 08/06/2012] [Indexed: 11/25/2022]
Abstract
Schizosaccharomyces pombe is a non-Saccharomyces yeast strain that can ferment grape musts with high sugar contents - but it also has other metabolic and physiological properties that render it of great interest to wine biotechnologists. This work compares the production of pyranoanthocyanins by S. pombe, Saccharomyces cerevisiae and Saccharomyces uvarum during fermentation. Total pyranoanthocyanins ranged from 11.9 to 19.4 mg/l depending on the strain of S. pombe used. On average, S. pombe produced more pyruvic acid than did either Saccharomyces species; as a consequence it also formed more vitisin A-type pigments. S. pombe 938 produced the largest quantity of vitisin A (11.03±0.82 mg/l). The formation of large amounts of pyranoanthocyanins intensifies the post-fermentation colour of wines somewhat, a phenomenon that helps them maintain their colour over ageing as the natural grape anthocyanins become degraded. Some of the S. pombe strains showed hydroxycinnamate decarboxylase activity, which favours the formation of vinylphenolic pyranoanthocyanins. Fermentation with S. pombe therefore provides an interesting way of increasing the overall pyranoanthocyanin content of red wines, and of stabilising their colour during ageing.
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Cold pasteurisation of red wines with high hydrostatic pressure to control Dekkera/Brettanomyces: effect on both aromatic and chromatic quality of wine. Eur Food Res Technol 2012. [DOI: 10.1007/s00217-012-1742-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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24
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Reduction of wine 4-ethylphenol concentration using lyophilised yeast as a bioadsorbent: influence on anthocyanin content and chromatic variables. Eur Food Res Technol 2011. [DOI: 10.1007/s00217-011-1470-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Mediterranean diet and the incidence of cardiovascular disease: a Spanish cohort. Nutr Metab Cardiovasc Dis 2011; 21:237-244. [PMID: 20096543 DOI: 10.1016/j.numecd.2009.10.005] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2009] [Revised: 07/13/2009] [Accepted: 10/20/2009] [Indexed: 10/19/2022]
Abstract
BACKGROUND AND AIM The Mediterranean diet is considered a model for healthy eating. However, prospective evidence in Mediterranean countries evaluating the relationship between this dietary pattern and non-fatal cardiovascular events is scarce. The aim of the present study was to evaluate the association between the adherence to the Mediterranean diet and the incidence of fatal and non-fatal cardiovascular events among initially healthy middle-aged adults from the Mediterranean area. METHODS AND RESULTS We followed-up 13,609 participants (60 percent women, mean age: 38 years) initially free of cardiovascular disease (CVD) during 4.9 years. Participants were part of a prospective cohort study of university graduates from all regions of Spain. Baseline diet was assessed using a validated 136-item food-frequency questionnaire. A 9-point score was used to appraise adherence to the Mediterranean diet. Incident clinical events were confirmed by a review of medical records. We observed 100 incident cases of CVD. In multivariate analyses, participants with the highest adherence to the Mediterranean diet (score>6) exhibited a lower cardiovascular risk (hazard ratio=0.41, 95% confidence interval [CI]: 0.18-0.95) compared to those with the lowest score (<3). For each 2-point increment in the score, the adjusted hazard ratios were 0.80 (95% CI: 0.62-1.02) for total CVD and 0.74 (0.55-0.99) for coronary heart disease. CONCLUSIONS There is an inverse association between adherence to the Mediterranean diet and the incidence of fatal and non-fatal CVD in initially healthy middle-aged adults.
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Formation of vinylphenolic pyranoanthocyanins by Saccharomyces cerevisiae and Pichia guillermondii in red wines produced following different fermentation strategies. Food Chem 2011. [DOI: 10.1016/j.foodchem.2010.05.096] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Symbolic dynamic analysis of relations between cardiac and breathing cycles in patients on weaning trials. Ann Biomed Eng 2010; 38:2542-52. [PMID: 20405218 PMCID: PMC2900596 DOI: 10.1007/s10439-010-0027-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2009] [Accepted: 03/25/2010] [Indexed: 11/21/2022]
Abstract
Traditional time-domain techniques of data analysis are often not sufficient to characterize the complex dynamics of the cardiorespiratory interdependencies during the weaning trials. In this paper, the interactions between the heart rate (HR) and the breathing rate (BR) were studied using joint symbolic dynamic analysis. A total of 133 patients on weaning trials from mechanical ventilation were analyzed: 94 patients with successful weaning (group S) and 39 patients that failed to maintain spontaneous breathing (group F). The word distribution matrix enabled a coarse-grained quantitative assessment of short-term nonlinear analysis of the cardiorespiratory interactions. The histogram of the occurrence probability of the cardiorespiratory words presented a higher homogeneity in group F than in group S, measured with a higher number of forbidden words in group S as well as a higher number of words whose probability of occurrence is higher than a probability threshold in group S. The discriminant analysis revealed the best results when applying symbolic dynamic variables. Therefore, we hypothesize that joint symbolic dynamic analysis provides enhanced information about different interactions between HR and BR, when comparing patients with successful weaning and patients that failed to maintain spontaneous breathing in the weaning procedure.
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Prevalencia del síndrome metabólico en la población general de la provincia de Cáceres (Estudio SIMCA). Semergen 2009. [DOI: 10.1016/s1138-3593(09)73107-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Minimization of ethylphenol precursors in red wines via the formation of pyranoanthocyanins by selected yeasts. Int J Food Microbiol 2009; 132:145-52. [DOI: 10.1016/j.ijfoodmicro.2009.04.015] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2008] [Revised: 04/03/2009] [Accepted: 04/18/2009] [Indexed: 10/20/2022]
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Effect on the autolysis process and the colouring matter of several commercial preparations with β-glucanase action in red winemaking. Eur Food Res Technol 2009. [DOI: 10.1007/s00217-009-1078-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Abstract
AIMS The formation of ethylphenols in wines, a consequence of Dekkera/Brettanomyces metabolism, can affect their quality. The main aims of this work were to further our knowledge of Dekkera/Brettanomyces with respect to ethylphenol production, and to develop a methodology for detecting this spoilage yeast and for estimating its population size in wines using differential-selective media and high performance liquid chromatography (HPLC). METHODS AND RESULTS This work examines the reduction of p-coumaric acid and the formation of 4-vinylphenol and 4-ethylphenol (recorded by HPLC-DAD) in a prepared medium because of the activities of different yeast species and populations. A regression model was constructed for estimating the population of Dekkera/Brettanomyces at the beginning of fermentation via the conversion of hydroxycinnamic acids into ethylphenols. CONCLUSIONS The proposed methodology allows the populations of Dekkera/Brettanomyces at the beginning of fermentation to be estimated in problem wines. Moreover, it avoids false positives because of yeasts resistant to the effects of the selective elements of the medium. SIGNIFICANCE AND IMPACT OF THE STUDY This may help prevent the appearance of organoleptic anomalies in wines at the winery level.
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Factors Affecting the Hydroxycinnamate Decarboxylase/Vinylphenol Reductase Activity ofDekkera/Brettanomyces: Application forDekkera/BrettanomycesControl in Red Wine Making. J Food Sci 2009; 74:M15-22. [DOI: 10.1111/j.1750-3841.2008.00977.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Respiratory muscle oxygen saturation during weaning. Crit Care 2009. [PMCID: PMC4083912 DOI: 10.1186/cc7190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Abstract
OBJECTIVE To assess the relation between adherence to a Mediterranean diet and the incidence of diabetes among initially healthy participants. DESIGN Prospective cohort study with estimates of relative risk adjusted for sex, age, years of university education, total energy intake, body mass index, physical activity, sedentary habits, smoking, family history of diabetes, and personal history of hypertension. SETTING Spanish university department. PARTICIPANTS 13 380 Spanish university graduates without diabetes at baseline followed up for a median of 4.4 years. MAIN OUTCOME MEASURES Dietary habits assessed at baseline with a validated 136 item food frequency questionnaire and scored on a nine point index. New cases of diabetes confirmed through medical reports and an additional detailed questionnaire posted to those who self reported a new diagnosis of diabetes by a doctor during follow-up. Confirmed cases of type 2 diabetes. RESULTS Participants who adhered closely to a Mediterranean diet had a lower risk of diabetes. The incidence rate ratios adjusted for sex and age were 0.41 (95% confidence interval 0.19 to 0.87) for those with moderate adherence (score 3-6) and 0.17 (0.04 to 0.75) for those with the highest adherence (score 7-9) compared with those with low adherence (score <3). In the fully adjusted analyses the results were similar. A two point increase in the score was associated with a 35% relative reduction in the risk of diabetes (incidence rate ratio 0.65, 0.44 to 0.95), with a significant inverse linear trend (P=0.04) in the multivariate analysis. CONCLUSION Adherence to a Mediterranean diet is associated with a reduced risk of diabetes.
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Adherence to Mediterranean diet and risk of developing diabetes: prospective cohort study. BMJ (CLINICAL RESEARCH ED.) 2008. [PMID: 18511765 DOI: 10.1136/bmj.39561.501007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVE To assess the relation between adherence to a Mediterranean diet and the incidence of diabetes among initially healthy participants. DESIGN Prospective cohort study with estimates of relative risk adjusted for sex, age, years of university education, total energy intake, body mass index, physical activity, sedentary habits, smoking, family history of diabetes, and personal history of hypertension. SETTING Spanish university department. PARTICIPANTS 13 380 Spanish university graduates without diabetes at baseline followed up for a median of 4.4 years. MAIN OUTCOME MEASURES Dietary habits assessed at baseline with a validated 136 item food frequency questionnaire and scored on a nine point index. New cases of diabetes confirmed through medical reports and an additional detailed questionnaire posted to those who self reported a new diagnosis of diabetes by a doctor during follow-up. Confirmed cases of type 2 diabetes. RESULTS Participants who adhered closely to a Mediterranean diet had a lower risk of diabetes. The incidence rate ratios adjusted for sex and age were 0.41 (95% confidence interval 0.19 to 0.87) for those with moderate adherence (score 3-6) and 0.17 (0.04 to 0.75) for those with the highest adherence (score 7-9) compared with those with low adherence (score <3). In the fully adjusted analyses the results were similar. A two point increase in the score was associated with a 35% relative reduction in the risk of diabetes (incidence rate ratio 0.65, 0.44 to 0.95), with a significant inverse linear trend (P=0.04) in the multivariate analysis. CONCLUSION Adherence to a Mediterranean diet is associated with a reduced risk of diabetes.
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Closed Tracheal Suction Systems Versus Open Tracheal Suction Systems for Mechanically Ventilated Adult Patients. Anesth Analg 2008. [DOI: 10.1213/ane.0b013e3181678c9c] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Information flow to assess cardiorespiratory interactions in patients on weaning trials. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2008; 2006:1462-5. [PMID: 17946466 DOI: 10.1109/iembs.2006.260390] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Nonlinear processes of the autonomic nervous system (ANS) can produce breath-to-breath variability in the pattern of breathing. In order to provide assess to these nonlinear processes, nonlinear statistical dependencies between heart rate variability and respiratory pattern variability are analyzed. In this way, auto-mutual information and cross-mutual information concepts are applied. This information flow analysis is presented as a short-term non linear analysis method to investigate the information flow interactions in patients on weaning trials. 78 patients from mechanical ventilation were studied: Group A of 28 patients that failed to maintain spontaneous breathing and were reconnected; Group B of 50 patients with successful trials. The results show lower complexity with an increase of information flow in group A than in group B. Furthermore, a more (weakly) coupled nonlinear oscillator behavior is observed in the series of group A than in B.
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Patients on weaning trials from mechanical ventilation classified with neural networks and feature selection. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2008; 2006:2195-8. [PMID: 17946503 DOI: 10.1109/iembs.2006.259607] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
One of the challenges in intensive care is the process of weaning from mechanical ventilation. We studied the differences in respiratory pattern variability between patients capable of maintaining spontaneous breathing during weaning trials and patients that fail to maintain spontaneous breathing. In this work, neural networks were applied to study these differences. 64 patients from mechanical ventilation are studied: Group S with 32 patients with Successful trials and Group F with 32 patients that Failed to maintain spontaneous breathing and were reconnected. A performance of 64.56% of well classified patients was obtained using a neural network trained with the whole set of 35 features. After the application of a feature selection procedure (backward selection) 84.56% was obtained using only 8 of the 35 features.
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Support vector machine classification applied on weaning trials patients. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2008; 2006:5587-90. [PMID: 17947151 DOI: 10.1109/iembs.2006.259440] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
One of the most frequent reasons for instituting mechanical ventilation is to decrease patient's work of breathing. Many attempts have been made to increase the effectiveness of the evaluation of the respiratory pattern with the analysis of the respiratory signals. This work proposes a method for the study of the differences in respiratory pattern variability in patients on weaning trials. The proposed method is based on a support vector machine using 35 features extracted from the respiratory flow signal. In this paper, a group of 146 patients with mechanical ventilation were studied: group S of 79 patients with successful weaning trials and group F of 67 patients that failed to maintain spontaneous breathing and were reconnected. Applying a feature selection procedure based on the use of the support vector machine with a leave-one-out cross-validation, it was obtained 86.67% of well classified patients on group S and 73.34% on group F, using only 8 of the 35 features. Therefore, support vector machine can be a classification method of the respiratory pattern variability useful in the study of patients on weaning trials.
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Study of the respiratory pattern variability in patients during weaning trials. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2007; 2004:3909-12. [PMID: 17271151 DOI: 10.1109/iembs.2004.1404093] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Mechanical ventilators are used to provide life support in patients with respiratory failure. One of the challenges in intensive care is the process of weaning from mechanical ventilation. We studied the differences in respiratory pattern variability between patients capable of maintaining spontaneous breathing during weaning trials and patients that fail to maintain spontaneous breathing. The respiratory pattern was characterized by the following time series: inspiratory time (T(I)), expiratory time (T(E)), breath duration (T(Tot)), tidal volume (V(T)), fractional inspiratory time (T(I)/T(Tot)), mean inspiratory flow (V(T)/T(I)), respiratory frequency (f), and rapid shallow breathing index (f/V(T)). The variational activity of breathing was partitioned into autoregressive, periodic and white noise fractions. Patients with unsuccessful trial presented a tendency to higher values of gross variability of V(T)/T(I) and f/V(T), and lower values of T(I). The autocorrelation coefficients tended to present higher values for T(I), T(I)/T(Tot) and V(T)/T(I). During both successful and unsuccessful T-tube test uncorrelated random behavior constituted > 75% of the variance of each time breath components and represented 50 to 70% in the breath component related to V(T). Correlated behavior represented 6 to 21% in time components and 28 to 50% in component related to V(T).
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Analysis of Respiratory Flow Signals in Chronic Heart Failure Patients with Periodic Breathing. ACTA ACUST UNITED AC 2007; 2007:307-10. [DOI: 10.1109/iembs.2007.4352285] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Joint symbolic dynamic analysis of cardiorespiratory interactions in patients on weaning trials. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2007; 2005:4576-9. [PMID: 17281258 DOI: 10.1109/iembs.2005.1615488] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Assessing autonomic control provides information about patho-physiological imbalances. Measures of variability of the cardiac interbeat duration RR(n) and the variability of the breath duration T<inf>Tot</inf>(n) are sensitive to those changes. The interactions between RR(n) and T<inf>Tot</inf>(n) are complex and strongly non-linear. A study of joint symbolic dynamics is presented as a new short-term non-linear analysis method to investigate these interactions in patients on weaning trials. 78 patients from mechanical ventilation are studied: Group A (patients that failed to maintain spontaneous breathing and were reconnected) and Group B (patients with successful trials). Using the concept of joint symbolic dynamics, cardiac and respiratory changes were transformed into a word series, and the probability of occurrence of each word type was calculated and compared between both groups. Significant differences were found in 13 words, and the most significant p<inf>n</inf>(W<inf>c010, r010</inf>): 0.0041 ± 0.0036 (group A) against 0.0012 ± 0.0024 (group B), p-value = 0.00001. The number of seldom occurring word types (forbidden words) also presents significant differences fw<inf>cr</inf>: 6.9 ± 6.6 against 13.5 ± 5.3, p-value = 0.00004. Joint symbolic dynamics provides an efficient non-linear representation of cardiorespiratory interactions that offers simple physiological interpretations.
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Modeling and evaluation of respiratory and muscle pattern during hypercapnic stimulus. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2007; 2004:3913-6. [PMID: 17271152 DOI: 10.1109/iembs.2004.1404094] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Understanding the respiratory control system and the ventilatory pattern under hypercapnic stimulus is important to interpret the acute exacerbation of COPD and the condition of patients connected to mechanical ventilation. The purpose of this study is the analysis of respiratory and muscle parameters in order to obtain the most sensitive and characteristic of different levels of hypercapnic stimulus. Parameters defined and calculated from pressure signals show the highest variations with the increment of stimulus. Other ones like exhaled ventilation or ratios between respiratory parameters are more influenced by hypercapnia than tidal volume, respiratory frequency or even end tidal CO2. Muscle parameters from electromyographic signals of three respiratory muscles are calculated in time and frequency domain. In spite of greater variability between subjects, the most interesting muscles because of their activation with higher stimulus are in the following order: diaphragm, sternomastoid and genioglossus. Moreover, a model of respiratory control system is evaluated in order to predict and simulate appropriately this ventilatory stimulus. In spite of scattered real data, they are compared with simulation results obtained by the model and predicted by means of a specific respiratory optimization.
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Analysis of the nonlinear autodependencies of respiratory pattern in patients on weaning trials. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2007; 2006:542-5. [PMID: 17271733 DOI: 10.1109/iembs.2004.1403214] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Traditional time domain techniques of data analysis are often not sufficient to characterize the nonlinear dynamics of respiration. In this study, the respiratory pattern variability was analyzed using auto mutual information measures. These provide access to nonlinear statistical autodependencies of respiratory pattern variability. A group of 20 patients on weaning trials from mechanical ventilation were studied at two different pressure support ventilation levels, in order to obtain respiratory volume signals with different variability. Time series of breathing duration, inspiratory time, fractional inspiratory time, tidal volume and mean inspiratory flow were analyzed. Different measures based on auto-mutual information were studied to characterize the respiratory pattern variability with regard to its complex organization.
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[Cyclosporin A causes oxidative stress and mitochondrial dysfunction in renal tubular cells]. Nefrologia 2007; 27:565-573. [PMID: 18045032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023] Open
Abstract
Reactive oxygen species (ROS) have been implicated in cyclosporin A (CsA) nephrotoxicity. As mitochondria are one of the main sources of ROS in cells, we evaluated the role of CsA in mitochondrial structure and function in LLC-PK1 cells. We incubated cells with CsA 1 microM for 24 hours and studies were performed with flow citometry and confocal microscopy. We studied mitochondrial NAD(P)H content, superoxide anion (O2.-) production (MitoSOX Red), oxidation of cardiolipin of inner mitochondrial membrane (NAO) and mitochondrial membrane potential (DIOC2(3)). Also we analyzed the intracellular ROS synthesis (H2DCF-DA) and reduced glutation (GSH) of cells. Our results showed that CsA decreased NAD(P)H and membrane potential, and increased O2.- in mitochondria. CsA also provoked oxidation of cardiolipin. Furthermore, CsA increased intracellular ROS production and decreased GSH content. These results suggest that CsA has crucial effects in mitochondria. CsA modified mitochondrial physiology through the decrease of antioxidant mitochondrial compounds as NAD(P)H and the dissipation of mitochondrial membrane potential and increase of oxidants as O2.-. Also, CsA alters lipidic structure of inner mitochondrial membrane through the oxidation of cardiolipin. These effects trigger a chain of events that favour intracellular synthesis of ROS and depletion of GSH that can compromise cellular viability. Nephrotoxic cellular effects of CsA can be explained, at least in part, through its influence on mitochondrial functionalism.
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Abstract
Traditional time domain techniques of data analysis are often not sufficient to characterize the complex dynamics of respiration. In this paper, the respiratory pattern variability is analyzed using symbolic dynamics. A group of 20 patients on weaning trials from mechanical ventilation are studied at two different pressure support ventilation levels, in order to obtain respiratory volume signals with different variability. Time series of inspiratory time, expiratory time, breathing duration, fractional inspiratory time, tidal volume and mean inspiratory flow are analyzed. Two different symbol alphabets, with three and four symbols, are considered to characterize the respiratory pattern variability. Assessment of the method is made using the 40 respiratory volume signals classified using clinical criteria into two classes: low variability (LV) or high variability (HV). A discriminant analysis using single indexes from symbolic dynamics has been able to classify the respiratory volume signals with an out-of-sample accuracy of 100%.
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[Moderate alcohol consumption and mortality for various reasons]. Aten Primaria 2005; 36:104-11. [PMID: 15989833 PMCID: PMC7676054 DOI: 10.1157/13076606] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2004] [Accepted: 09/07/2004] [Indexed: 11/21/2022] Open
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Variability analysis of the respiratory volume based on non-linear prediction methods. Med Biol Eng Comput 2004; 42:86-91. [PMID: 14977227 DOI: 10.1007/bf02351015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
This work proposed and studied a method of automatically classifying respiratory volume signals as high or low variability by means of non-linear analysis of the respiratory volume. The analysis used volume signals generated by the respiratory system to construct a model of its dynamics and to estimate the quality of the predictions made with the model. Different methods of prediction evaluation, prediction horizons and embedding dimensions were also analysed. Assessment of the method was made using a database that contained 40 respiratory volume signals classified using clinical criteria into two classes: low or high variability. The results obtained using the method of surrogate data provided evidence of non-linear determinism in the respiratory volume signals. A discriminant analysis carried out using non-linear prediction variables classified the respiratory volume signals with an accuracy of 95%.
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Estimating respiratory pattern variability by symbolic dynamics. Methods Inf Med 2004; 43:22-5. [PMID: 15026830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
OBJECTIVES The traditional techniques of data analysis are often not sufficient to characterize the complex dynamics of respiration. In this study the respiratory pattern variability was analyzed using symbolic dynamics. METHODS A group of 20 patients on weaning trials from mechanical ventilation were studied at two different pressure support ventilation levels. Breath duration (T(TOT)) time series and the relation T(I)/T(TOT), that contains the influence of inspiratory time (T(I)), were considered. Length-3 words and 3 different symbols were proposed. The incidence of the overlapping tau and the parameter alpha were analyzed. RESULTS From the breath duration time series, the distribution of words with probability of occurrence higher than 6% was concentrated on one word for low respiratory variability, whereas high variability was characterized by 4 words, presenting a statistically significant difference (p </= 0.0005). The probability occurrence of words "110" and "111" was also significantly different (p</= 0.0005) when comparing both variabilities. CONCLUSION The analysis carried out obtained discriminant functions able to correctly classify all the testing set series. These results permit the consideration of symbolic dynamics as a promising methodology to study the respiratory pattern variability.
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