549 research outputs found

    Genotypic and Phenotypic Heterogeneity in Alicyclobacillus acidoterrestris: A Contribution to Species Characterization.

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    Alicyclobacillus acidoterrestris is the main cause of most spoilage problems in fruit juices and acidic products. Since soil borne species often contaminate fruit juices and do not need strict extreme requirements for survival, it is a great concern to investigate whether and how soil species could evolve from their ecological niches in microbial community to new environments as fruit juices. In this study, 23 isolates of thermo-acidophilic, spore-forming bacteria from soil were characterized by cultural and molecular methods. In addition, 2 strains isolated from a spoilage incident in pear juice were typed. Strains phenotyping showed that they could be grouped into 3 different clusters, and some isolates showed identical or quite similar patterns. Analyzing pH and temperature ranges for growth, the majority of strains were able to grow at values described for many species of Alicyclobacillus. Qualitative utilization of lysine, arginine and indole production from tryptophan revealed, for the first time, deamination of lysine and decarboxylation of arginine. Resistance to 5% NaCl as well as the ability to hydrolyze starch and gelatin, nitrate reduction, catalase and oxidase activities confirmed literature evidences. Examining of 16S rRNA, showed that isolates were divided into three blocks represented by effectively soil species and strains that are moving from soil to other possible growing source characterized by parameters that could strongly influence bacterial survival. RAPD PCR technique evidenced a great variability in banding patterns and, although it was not possible to obtain genotypically well-distinguished groups, it was feasible to appreciate genetic similarity between some strains. In conclusion, the investigation of a microbial community entails a combination of metagenomic and classic culturedependent approaches to expand our knowledge about Alicyclobacillus and to look for new subspecies

    Human west nile virus lineage 2 infection: Epidemiological, clinical, and virological findings

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    West Nile virus (WNV) lineage 2 is expanding and causing large outbreaks in Europe. In this study, we analyzed the epidemiological, clinical, and virological features of WNV lineage 2 infection during the large outbreak that occurred in northern Italy in 2018. The study population included 86 patients with neuroinvasive disease (WNND), 307 with fever (WNF), and 34 blood donors. Phylogenetic analysis of WNV full genome sequences from patients' samples showed that the virus belonged to the widespread central/southern European clade of WNV lineage 2 and was circulating in the area at least since 2014. The incidence of WNND and WNF progressively increased with age and was higher in males than in females. Among WNND patients, the case fatality rate was 22%. About 70% of blood donors reported symptoms during follow-up. Within the first week after symptom onset, WNV RNA was detectable in the blood or urine of 80% of patients, while 20% and 40% of WNND and WNF patients, respectively, were WNV IgM-seronegative. In CSF samples of WNND patients, WNV RNA was typically detectable when WNV IgM antibodies were absent. Blunted or no WNV IgM response and high WNV IgG levels were observed in seven patients with previous flavivirus immunity

    Adalimumab dose tapering in patients with rheumatoid arthritis who are in long-standing clinical remission: results of the phase IV PREDICTRA study

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    Objective: To investigate the association between baseline disease activity and the occurrence of flares after adalimumab tapering or withdrawal in patients with rheumatoid arthritis (RA) in sustained remission. Methods: The PREDICTRA phase IV, randomised, double-blind (DB) study (ImPact of Residual Inflammation Detected via Imaging TEchniques, Drug Levels, and Patient Characteristics on the Outcome of Dose TaperIng of Adalimumab in Clinical Remission Rheumatoid ArThritis (RA) Patients) enrolled patients with RA receiving adalimumab 40 mg every other week who were in sustained remission ≥6 months. After a 4-week, open-label lead-in (OL-LI) period, patients were randomised 5:1 to DB adalimumab taper (every 3 weeks) or withdrawal (placebo) for 36 weeks. The primary endpoint was the association between DB baseline hand and wrist MRI-detected inflammation with flare occurrence. Results: Of 146 patients treated during the OL-LI period, 122 were randomised to taper (n=102) or withdrawal (n=20) arms. Patients had a mean 12.9 years of active disease and had received adalimumab for a mean of 5.4 years (mean 2.2 years in sustained remission). Overall, 37 (36%) and 9 (45%) patients experienced a flare in the taper and withdrawal arms, respectively (time to flare, 18.0 and 13.3 weeks). None of the DB baseline disease characteristics or adalimumab concentration was associated with flare occurrence after adalimumab tapering. Approximately half of the patients who flared regained clinical remission after 16 weeks of open-label rescue adalimumab. The safety profile was consistent with previous studies. Conclusions: Approximately one-third of patients who tapered adalimumab versus half who withdrew adalimumab experienced a flare within 36 weeks. Time to flare was numerically longer in the taper versus withdrawal arm. Baseline MRI inflammation was not associated with flare occurrence. Trial registration number: NCT02198651, EudraCT 2014-001114-26

    Controlled release of antimicrobial compounds from highly swellable polymers.

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    The suitability of antimicrobial release films made from highly swellable polymers for use in food packaging was evaluated. The possibility of modulating the release kinetics of active compounds either by regulating the degree of cross-link of the polymer matrix or by using multilayer structures was addressed. The release kinetics of lysozyme, nisin, and sodium benzoate (active compounds with different molecular weights) were determined at ambient temperature (25 degrees C). The effectiveness of the proposed active films in inhibiting microbial growth was addressed by determining the antimicrobial efficiency of the released active compounds. Micrococcus lysodeikticus, Alicyclobacillus acidoterrestris, and Saccharomyces cerevisiae were used to test the antimicrobial efficiency of released lysozyme, nisin, and sodium benzoate, respectively. Results indicate that the release kinetics of both lysozyme and nisin can be modulated through the degree of cross-link of the polymer matrix, whereas multilayer structures need to be used to control the release kinetics of sodium benzoate. All the active compounds released from the investigated active films were effective in inhibiting microbial growth

    Viability, Sublethal Injury, and Release of Cellular Components From Alicyclobacillus acidoterrestris Spores and Cells After the Application of Physical Treatments, Natural Extracts, or Their Components

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    Alicyclobacillus acidoterrestris is a spoiling microorganism regarded as one of the most important causes of spoilage of fruit juices and acidic products. In this paper, four strains of A. acidoterrestris (type strain-DSM 3922; two wild strains isolated from soil-C8 and C24; wild strain isolated from a spoiled pear juice CB1) were treated through natural extracts/active compounds from essential oils (EOs), and physical treatments were used to assess their susceptibility and the presence of sublethal injury. The characterization of damage was also performed. The results suggest that it is possible to control A. acidoterrestris through alternative approaches, although the effect relied upon the age of spores. In addition to the mere antimicrobial effect, some treatments could cause a sublethal injury on spores. Lemon extract was the most effective treatment for both the antimicrobial effect and the sublethal injury, as evidenced by the release of proteins, and calcium dipicolinate [dipicolinic acid (DPA)] by fresh spores and only DPA (with an exception for C8) by old spores. A sublethal injury with protein release was also found for physical treatments [US (ultrasound) or heating]. For the first time, this paper reports on the existence of a sublethal injury for A. acidoterrestris, and this evidence could also be a challenge, because injured microorganisms could restore their metabolism, or an opportunity to design new preserving treatments

    Intellectual disability, sensation and thinking through affect

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    Acute coronary syndromes (ACSs) represent a high-risk condition, as enhanced platelet reactivity importantly influences myocardial perfusion and procedural results after percutaneous coronary intervention (PCI). In fact, higher rate of periprocedural myocardial infarction (PMI) and reduced event-free survival have been reported in these patients. The single nucleotide polymorphism Leu33Pro of platelet glycoprotein IIIa has been related to an increased platelet reactivity, a lower response to antiplatelet agents and higher risk of stent restenosis. Therefore, our aim was to evaluate the impact of this polymorphism on PMI in patients undergoing PCI for non-ST-segment elevation MI (NSTEMI). Our population is represented by 478 consecutive patients undergoing coronary angioplasty for NSTEMI. Cardiac biomarkers were monitored at intervals from 8 to 48 h after the procedure. Genetic analysis was performed to assess the presence of Leu33Pro polymorphism. A total of 156 patients (32.6%) were polymorphic. Clinical features did not differ according to genetic status, neither pharmacological treatment pre and during angioplasty. PlA carriers had lower rate of calcifications (P = 0.01) and higher coronary tortuosity (P = 0.03) at angiography and underwent more frequently to thrombectomy (P = 0.05). PCI-related complications did not differ according to genotype. Leu33Pro polymorphism was not associated with increased risk of periprocedural myonecrosis and PMI even after correction for baseline differences, [odds ratio (OR) (95% confidence interval (CI) = 0.70 (0.44-1.13), P = 0.15 for PMI and OR (95% CI) = 0.77 (0.53-1.11), P = 0.17 for myonecrosis, respectively]. Results were confirmed in high-risk subgroups of patients. In conclusion, among patients undergoing PCI for ACS, the polymorphism Leu33Pro of platelet glycoprotein IIIa is not associated with increased risk of PMI

    Invariant Natural Killer T (iNKT) cells in HAART-treated, HIV-positive patients with bone and cardiovascular impairment

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    Background: Invariant Natural Killer T (iNKT) cells represent a determinant in the course of infections and diseases, however, their role in the pathogenesis of non-infectious co-morbidities in HIV-positive patients is unknown. Methods: Flow cytometry was used to investigate iNKT cell frequency, phenotype and function in HIV-infected patients on HAART with bone and/or cardiovascular disorders and in HIV-positive controls free from co-morbidities. Results: iNKT cells from subjects with bone and cardiovascular impairment expressed high levels of CD161 and predominantly secreted TNF. iNKT cells from individuals with bone disease alone did not show any distinctive phenotypical or functional characteristics. The functional capacity of iNKT cells in patients with cardiovascular disorder was impaired with no cytokine release upon stimulation. Conclusion: iNKT cells may have a role in non-infectious co-morbidities in treated HIV disease, possibly through the exacerbation of inflammation. Further studies are needed to investigate iNKT cells in the pathogenesis of non-communicable disorders in HIV infection

    Interpreting T-Cell Cross-reactivity through Structure: Implications for TCR-Based Cancer Immunotherapy

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    Immunotherapy has become one of the most promising avenues for cancer treatment, making use of the patient\u27s own immune system to eliminate cancer cells. Clinical trials with T-cell-based immunotherapies have shown dramatic tumor regressions, being effective in multiple cancer types and for many different patients. Unfortunately, this progress was tempered by reports of serious (even fatal) side effects. Such therapies rely on the use of cytotoxic T-cell lymphocytes, an essential part of the adaptive immune system. Cytotoxic T-cells are regularly involved in surveillance and are capable of both eliminating diseased cells and generating protective immunological memory. The specificity of a given T-cell is determined through the structural interaction between the T-cell receptor (TCR) and a peptide-loaded major histocompatibility complex (MHC); i.e., an intracellular peptide-ligand displayed at the cell surface by an MHC molecule. However, a given TCR can recognize different peptide-MHC (pMHC) complexes, which can sometimes trigger an unwanted response that is referred to as T-cell cross-reactivity. This has become a major safety issue in TCR-based immunotherapies, following reports of melanoma-specific T-cells causing cytotoxic damage to healthy tissues (e.g., heart and nervous system). T-cell cross-reactivity has been extensively studied in the context of viral immunology and tissue transplantation. Growing evidence suggests that it is largely driven by structural similarities of seemingly unrelated pMHC complexes. Here, we review recent reports about the existence of pMHC hot-spots for cross-reactivity and propose the existence of a TCR interaction profile (i.e., a refinement of a more general TCR footprint in which some amino acid residues are more important than others in triggering T-cell cross-reactivity). We also make use of available structural data and pMHC models to interpret previously reported cross-reactivity patterns among virus-derived peptides. Our study provides further evidence that structural analyses of pMHC complexes can be used to assess the intrinsic likelihood of cross-reactivity among peptide-targets. Furthermore, we hypothesize that some apparent inconsistencies in reported cross-reactivities, such as a preferential directionality, might also be driven by particular structural features of the targeted pMHC complex. Finally, we explain why TCR-based immunotherapy provides a special context in which meaningful T-cell cross-reactivity predictions can be made

    Environmental risk factors associated with biliary atresia in Rio Grande do sul, Brazil

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    Biliary atresia (BA) seems to be a multifactorial disorder in which environmental factors interact with the patient’s genetic constitution. This study aimed to analyze information concerning environmental risk factors associated with BA in southern Brazil. A case-control study with mothers of patients with BA and mothers of patients with cystic fibrosis (CF) was conducted. Inquiry included questions related to exposition to environmental risk factors during the periconceptional and gestational (second and third trimesters) periods. Mothers of BA patients had smoked during pregnancy more frequently in comparison with the mothers of CF patients, but no significant difference was found in a multivariate analysis. There was no between group difference in terms of seasonality, but the multivariate analysis showed a significant difference within the BA group between date of conception in winter compared to other seasons. In conclusion, smoking during pregnancy seemed to increase the risk of BA while date of conception in winter decreased it.info:eu-repo/semantics/publishedVersio
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