In vitro interactions of Alternaria mycotoxins, an emerging class of food contaminants, with the gut microbiota: a bidirectional relationship

The human gut microbiota plays an important role in the maintenance of human health. Factors able to modify its composition might predispose the host to the development of pathologies. Among the various xenobiotics introduced through the diet, Alternaria mycotoxins are speculated to represent a threat for human health. However, limited data are currently available about the bidirectional relation between gut microbiota and Alternaria mycotoxins. In the present work, we investigated the in vitro effects of different concentrations of a complex extract of Alternaria mycotoxins (CE; containing eleven mycotoxins; e.g. 0.153 µM alternariol and 2.3 µM altersetin, at the maximum CE concentration tested) on human gut bacterial strains, as well as the ability of the latter to metabolize or adsorb these compounds. Results from the minimum inhibitory concentration assay showed the scarce ability of CE to inhibit the growth of the tested strains. However, the growth kinetics of most of the strains were negatively affected by exposure to the various CE concentrations, mainly at the highest dose (50 µg/mL). The CE was also found to antagonize the formation of biofilms, already at concentrations of 0.5 µg/mL. LC–MS/MS data analysis of the mycotoxin concentrations found in bacterial pellets and supernatants after 24 h incubation showed the ability of bacterial strains to adsorb some Alternaria mycotoxins, especially the key toxins alternariol, alternariol monomethyl ether, and altersetin. The tendency of these mycotoxins to accumulate within bacterial pellets, especially in those of Gram-negative strains, was found to be directly related to their lipophilicity

Prevalence and characterization of methicillin-resistant Staphylococcus aureus among healthy children in a city of Argentina

Community acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) is a major global problem. Healthy carriers of S. aureus strains have an important role in the dissemination of this bacterium. The aim of this study was to estimate the prevalence of S. aureus and methicillin-resistant S. aureus (MRSA) carriage among healthy children in a city of Buenos Aires province, Argentina, and to determine the potential risk factors for its acquisition. We also described the molecular features of MRSA strains circulating in this population. S. aureus carriage was investigated in all children attending the last year of kindergarten during the 2008 school- year period. Household contacts of MRSA carriers were also screened. Of 316 healthy children, 98 (31.0%) carried S. aureus, including 14 MRSA carriers (4.4%) and 84 methicillin susceptible S. aureus (MSSA) carriers (26.6%). All MRSA isolates carried the SCCmec type IV cassette. Eight of the fourteen isolates were closely related to the clone responsible for most severe community- acquired MRSA infections caused in our country (CAA: PFGE A, SCCmec IV, spa t311, ST5). Two subtypes (A1 and A2) were distinguished in this group by PFGE. Both had agr type II and presented the same virulence determinants, except for PVL coding genes and sea that were only harbored by subtype A1. Our results, based on the analysis of MRSA isolates recovered in the screening of healthy children, provide evidence of a community reservoir of the major CA-MRSA clone described in Argentina.Fil: Gardella, N.. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; ArgentinaFil: Murzicato, S.. Hospital Municipal de San Antonio de Areco; ArgentinaFil: Di Gregorio, Sabrina Noelia. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; ArgentinaFil: Cuirolo, Arabela Ximena. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; ArgentinaFil: Desse, J.. Hospital Paroissien; ArgentinaFil: Crudo, F.. Hospital Municipal de San Antonio de Areco; ArgentinaFil: Gutkind, Gabriel Osvaldo. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; ArgentinaFil: Mollerach, Marta Eugenia. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentin

Postural control and disability in patients with early rheumatoid arthritis

PMID: 33427617 Abstract Objectives: Rheumatoid arthritis (RA) may affect the postural control through abnormal sensory inputs and impaired motor responses. Sensory Organization Test (SOT) objectively evaluates contribution of different sensorial afferences in postural control. The aim of the study is to assess mechanisms of postural instability and their relations with disability and disease characteristics in an early RA(ERA) cohort. Methods: The equilibrium scores were assessed in 30 ERA patients and 30 age- and sex-matched controls. The somatosensory (SOM), visual (VIS) and vestibular (VEST) ratios were computed to assess the use of different sensory and the composite equilibrium score (CES) as a measure of global balance performance. Results: ERA patients had lower CES (78.4±6.0% vs. 83.4±5.0%, p=0.002), SOM ratio (98.5±1.8% vs. 99.6±2.1%, p=0.035), VIS ratio (85.2±7.6% vs. 91.5±6.0%, p=0.001) and VEST ratio (70.8±10.0% vs. 80.3±7.8%, p<0.001) compared to controls. The presence of ankle arthritis correlated negatively to both SOM (r=-0.369, p=0.045) and VIS ratio (r=0.470, p=0.009), pain severity to CES (r=-0.389, p=0.045) and VIS ratio (r=-0.385, p=0.048) and HAQ-DI to CES (r=-0.591, p=0.001), SOM (r=-0.510, p=0.004) and VIS ratio (r=-0.390, p=0.033.). Patients-reported postural instability was associated with lower CES (75.4±5.4% vs. 80.7±5.5%, p=0.016) and VEST ratios (66.5±10.1% vs. 74.1±8.8%, p=0.036). SOT outcomes did not differ according to acute phase reactants, disease activity or autoantibody positivity. Conclusions: RA patients showed an early impairment of postural control related to the degree of disability and subjective postural instability. Our data suggest that the lack of balance could result from both impaired motor response and abnormal sensory organisation

From gut dysbiosis to altered brain function and mental illness: mechanisms and pathways

The human body hosts an enormous abundance and diversity of microbes, which perform a range of essential and beneficial functions. Our appreciation of the importance of these microbial communities to many aspects of human physiology has grown dramatically in recent years. We know, for example, that animals raised in a germ-free environment exhibit substantially altered immune and metabolic function, while the disruption of commensal microbiota in humans is associated with the development of a growing number of diseases. Evidence is now emerging that, through interactions with the gut-brain axis, the bidirectional communication system between the central nervous system and the gastrointestinal tract, the gut microbiome can also influence neural development, cognition and behaviour, with recent evidence that changes in behaviour alter gut microbiota composition, while modifications of the microbiome can induce depressive-like behaviours. Although an association between enteropathy and certain psychiatric conditions has long been recognized, it now appears that gut microbes represent direct mediators of psychopathology. Here, we examine roles of gut microbiome in shaping brain development and neurological function, and the mechanisms by which it can contribute to mental illness. Further, we discuss how the insight provided by this new and exciting field of research can inform care and provide a basis for the design of novel, microbiota-targeted, therapies.GB Rogers, DJ Keating, RL Young, M-L Wong, J Licinio, and S Wesseling

A new algorithm for energy-driven data compression in VLIW embedded processors

This paper presents a new algorithm for on-the-fly data compression in high performance VLIW processors. The algorithm aggressively targets energy minimization of some of the dominant factors in the SoC energy budget (i.e., main memory access and high throughput global bus). Based on a differential technique, both the new algorithm and the HW compression unit have been developed to efficiently manage data compression and decompression into a high performance industrial processor architecture, under strict real time constraints (Lx-ST200: a 4-issue, 6-stage pipelined VLIW processor with on-chip D and I-cache). The original data-cache line is compressed before write-back to main memory and, then, decompressed whenever cache refill takes place. An extensive experimental strategy has been developed for the specific validation of the target Lx processor. In order to allow public comparison, we also report the results obtained on a MIPS pipelined RISC processor simulated with SimpleScalar. The two platforms have been benchmarked over Ptolemy and MediaBench programs. Energy savings provided by the application of the proposed technique range from 10% to 22% on the Lx-ST200 platform and from 11% to 14% on the MIPS platform