52 research outputs found

    Methodology for predicting oily mixture properties in the mathematical modeling of molecular distillation

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    A methodology for predicting the thermodynamic and transport properties of a multi-component oily mixture, in which the different mixture components are grouped into a small number of pseudo components is shown. This prediction of properties is used in the mathematical modeling of molecular distillation, which consists of a system of differential equations in partial derivatives, according to the principles of the Transport Phenomena and is solved by an implicit finite difference method using a computer code. The mathematical model was validated with experimental data, specifically the molecular distillation of a deodorizer distillate (DD) of sunflower oil. The results obtained were satisfactory, with errors less than 10% with respect to the experimental data in a temperature range in which it is possible to apply the proposed method.Fil: Gayol, Maria Fernanda. Universidad Nacional de Rio Cuarto. Facultad de Ingeniería. Departamento de Tecnología Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Pramparo, Maria del Carmen. Universidad Nacional de Rio Cuarto. Facultad de Ingeniería. Departamento de Tecnología Química; ArgentinaFil: Miro Erdmann, Silvia M.. Universidad Nacional de San Luis. Facultad de Ingeniería y Ciencias Agropecuarias; Argentin

    Expert Opinion on Dose Regimen and Therapeutic Drug Monitoring for Long-Term Use of Dalbavancin: Expert Review Panel

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    Background: Dalbavancin is a lipoglycopeptide with a long elimination half-life, currently licensed for the treatment of acute bacterial skin and skin structure infections (ABSSSI) in adults. Dalbavancin's potential in treating off-label complex gram-positive infections is promising and real-world experience in treating such infections is growing. However, clear guidance on extended dosing regimens is lacking. Objectives: We aim to provide clear expert opinion based on recent pharmacokinetic literature and expert and real-world experience in infection areas that require >2 weeks of treatment. Methods: A single face-to-face meeting was held in September 2022 to collate expert opinion and present safety data of dalbavancin use in these clinical indications. A survey was completed by all authors on their individual experience with dalbavancin which highlighted the heterogeneity in the regimens used. Results: After review of the survey data and recent literature, we present expert panel proposals which accommodate different healthcare settings and resource availability, and centre around the length of treatment duration including up to, or exceeding, 6 weeks. To achieve adequate dalbavancin concentrations for up to 6 weeks, 3,000mg of dalbavancin should be given over 4 weeks for the agreed complex infections requiring >2 weeks treatment. Therapeutic drug monitoring (TDM) is advised for longer treatment durations and in case of renal failure. Specific dosing recommendations for other special populations require further investigation. Conclusions: These proposals based on expert opinion have been defined to encourage best practice with dalbavancin to optimise its administration beyond the current approved licenced dose across different healthcare settings

    Current epidemiology and outcome of infective endocarditis: A multicenter, prospective, cohort study

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    ©2015 Wolters Kluwer Health, Inc.. This manuscript version is made available under the CC BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/. This document is the Published, version of a Published Work that appeared in final form in Medicine. To access the final edited and published work see https://doi.org/10.1097/MD.0000000000001816The aim of the study was to describe the epidemiologic and clinical characteristics and identify the risk factors of short-term and 1-year mortality in a recent cohort of patients with infective endocarditis (IE). From January 2008, multidisciplinary teams have prospectively collected all consecutive cases of IE, diagnosed according to the Duke criteria, in 25 Spanish hospitals. Overall, 1804 patients were diagnosed. The median age was 69 years (interquartile range, 55–77), 68.0% were men, and 37.1% of the cases were nosocomial or health care-related IE. Gram-positive microorganisms accounted for 79.3% of the episodes, followed by Gram-negative (5.2%), fungi (2.4%), anaerobes (0.9%), polymicrobial infections (1.9%), and unknown etiology (9.1%). Heart surgery was performed in 44.2%, and in-hospital mortality was 28.8%. Risk factors for in-hospital mortality were age, previous heart surgery, cerebrovascular disease, atrial fibrillation, Staphylococcus or Candida etiology, intracardiac complications, heart failure, and septic shock. The 1-year independent risk factors for mortality were age (odds ratio [OR], 1.02), neoplasia (OR, 2.46), renal insufficiency (OR, 1.59), and heart failure (OR, 4.42). Surgery was an independent protective factor for 1-year mortality (OR, 0.44). IE remains a severe disease with a high rate of in-hospital (28.9%) and 1-year mortality (11.2%). Surgery was the only intervention that significantly reduced 1-year mortality

    Epidemiological and clinical characteristics of Streptococcus tigurinus endocarditis

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    Background: Streptococcus tigurinus was recently described as a new streptococcal species within the viridans group streptococci (VGS). The objectives of the present work were to analyse the clinical and microbiological characteristics of S. tigurinus isolated from patients with bacteraemias, to determine the prevalence of S. tigurinus among VGS endocarditis in Spain, and to compare the clinical characteristics and outcomes of endocarditis caused by S. tigurinus and other VGS. Methods: Retrospective nationwide study, performed between 2008 and 2016 in 9 Spanish hospitals from 7 different provinces comprising 237 cases of infective endocarditis. Streptococcal isolates were identified by sequencing fragments of their 16S rRNA, sodA and groEL genes. Clinical data of patients with streptococcal endocarditis were prospectively collected according to a pre-established protocol. Results: Patients with endocarditis represented 7/9 (77.8%) and 26/86 (30.2%) of the bacteraemias caused by S. tigurinus and other VGS, respectively (p < 0.001), in two of the hospital participants. Among patients with streptococcal endocarditis, 12 different Streptococcus species were recognized being S. oralis, S. tigurinus and S. mitis the three more common. No relevant statistical differences were observed in the clinical characteristics and outcomes of endocarditis caused by the different VGS species. Conclusions: In this multicenter study performed in Spain, S. tigurinus showed a higher predilection for the endocardial endothelium as compared to other VGS. However, clinical characteristics and outcomes of endocarditis caused by S. tigurinus did not significantly differ from endocarditis caused by other oral streptococci.JMM received a personal 80:20 research grant from the Institut d’InvestigacionsBiomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain during 2017–19. Nofunding entity played any role in the design of the study and data collection,analysis, and interpretation of data and in writing the manuscript

    Retinol binding protein 4 and retinol in steatotic and nonsteatotic rat livers in the setting of partial hepatectomy under ischemia/reperfusion

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    Steatotic livers show increased hepatic damage and impaired regeneration after partial hepatectomy (PH) under ischemia/reperfusion (I/R), which is commonly applied in clinical practice to reduce bleeding. The known function of retinol-binding protein 4 (RBP4) is to transport retinol in the circulation. We examined whether modulating RBP4 and/or retinol could protect steatotic and nonsteatotic livers in the setting of PH under I/R. Steatotic and nonsteatotic livers from Zucker rats were subjected to PH (70%) with 60 minutes of ischemia. RBP4 and retinol levels were measured and altered pharmacologically, and their effects on hepatic damage and regeneration were studied after reperfusion. Decreased RBP4 levels were observed in both liver types, whereas retinol levels were reduced only in steatotic livers. RBP4 administration exacerbated the negative consequences of liver surgery with respect to damage and liver regeneration in both liver types. RBP4 affected the mobilization of retinol from steatotic livers, and this revealed actions of RBP4 independent of simple retinol transport. The injurious effects of RBP4 were not due to changes in retinol levels. Treatment with retinol was effective only for steatotic livers. Indeed, retinol increased hepatic injury and impaired liver regeneration in nonsteatotic livers. In steatotic livers, retinol reduced damage and improved regeneration after surgery. These benefits of retinol were associated with a reduced accumulation of hepatocellular fat. Thus, strategies based on modulating RBP4 could be ineffective and possibly even harmful in both liver types in the setting of PH under I/R. In terms of clinical applications, a retinol pretreatment might open new avenues for liver surgery that specifically benefit the steatotic liver. Liver Transpl 18:1198-1208, 2012. (c) 2012 AASLD.Spanish Ministry of Science and Innovation [BFU2009-07410]Agency for the Innovation and Internationalization of Catalan Enterprise [VALTEC08-2-0033]Agency for the Support and Evaluation of Graduate Education (Brazilian Ministry of Education)Spanish Society for Liver Transplantation Foundatio

    Intracellular expression of Tat alters mitochondrial functions in T cells: a potential mechanism to understand mitochondrial damage during HIV-1 replication

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    HIV-1 replication results in mitochondrial damage that is enhanced during antiretroviral therapy (ART). The onset of HIV-1 replication is regulated by viral protein Tat, a 101-residue protein codified by two exons that elongates viral transcripts. Although the first exon of Tat (aa 1–72) forms itself an active protein, the presence of the second exon (aa 73–101) results in a more competent transcriptional protein with additional functions. Results: Mitochondrial overall functions were analyzed in Jurkat cells stably expressing full-length Tat (Tat101) or one-exon Tat (Tat72). Representative results were confirmed in PBLs transiently expressing Tat101 and in HIV-infected Jurkat cells. The intracellular expression of Tat101 induced the deregulation of metabolism and cytoskeletal proteins which remodeled the function and distribution of mitochondria. Tat101 reduced the transcription of the mtDNA, resulting in low ATP production. The total amount of mitochondria increased likely to counteract their functional impairment. These effects were enhanced when Tat second exon was expressed. Conclusions: Intracellular Tat altered mtDNA transcription, mitochondrial content and distribution in CD4+ T cells. The importance of Tat second exon in non-transcriptional functions was confirmed. Tat101 may be responsible for mitochondrial dysfunctions found in HIV-1 infected patients.We greatly appreciate the secretarial assistance of Mrs Olga Palao. This work was supported by FIPSE (360924/10), Spanish Ministry of Economy and Competitiveness (SAF2010-18388), Spanish Ministry of Health (EC11- 285), AIDS Network ISCIII-RETIC (RD12/0017/0015), Instituto de Salud Carlos III, Spanish Ministry of Economy and Competitiveness (FIS PI12/00506). The work of Sara Rodríguez-Mora is supported by a fellowship of Sara Borrell from Spanish Ministry of Economy and Competitiveness (2013). The work of María Rosa López-Huertas is supported by a fellowship of the European Union Programme Health 2009 (CHAARM).S

    Improving in vivo conversion of oleuropein into hydroxytyrosol by oral granules containing probiotic Lactobacillus plantarum 299v and an Olea europaea standardized extract

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    This study reports novel food-grade granules for co-delivery of L. plantarum 299v and a standardized extract of Olea europaea leaves (Phenolea®) as oral carrier of probiotics and hydroxytyrosol. Different granule formulations containing either L. plantarum 299v (Lac), or the olive leave extract (Phe) or their combination (Lac-Phe) have been successfully produced through wet granulation employing excipients generally regarded as safe as granulating/binding agents. L. plantarum cells withstood the manufacturing process and were stable upon storage at 4°C for more than 6 months. In vitro dissolution studies in simulated gastro-intestinal fluids showed the capability of the granules to rapidly dissolve and deliver both olive leave phenols and living L. plantarum cells. In simulated digestion conditions, Lac and Lac-Phe granules protected L. plantarum against the harsh environment of the gastro-intestinal tract. Co-administration of Lac and Phe oral granules to healthy mice provided for higher amounts of hydroxytyrosol in urines as compared to Phe granules alone, suggesting that L. plantarum 299v boosted in vivo conversion of oleuropein to hydroxytyrosol. On the other hand, PCR-assisted profiling of the Lactobacillus population in faeces obtained from mice treated with Lac or Lac plus Phe confirmed that the probiotic arrived alive to colon and was there able to exert a sort of perturbing effect on the climax colonic microflora. Overall, these results pave the way towards the development of a nutraceutical useful for combined delivery of bioactive hydroxytyrosol and probiotics to colon site
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