404 research outputs found
Effect of bicarbonate on growth of the oleaginous microalga Botryococcus braunii
The effect of bicarbonate, produced by the enzymatic hydration of CO2 from postcombustion fumes, was investigated on Botryococcus braunii growth. The NaHCO3, supplied to cultures in the role of inorganic carbon source is proposed as a more eco-sustainable alternative to gaseous
CO2. The salt was provided to the cultures at the final concentration of 0.5-1.5-2.5 g L-1. The growth rate was considered for specific time intervals (T0-T5, T5-T10 and T0-T10) showing values significantly higher in the culture supplemented with 2.5 g L-1 bicarbonate. The doubling times were also
considered in all experimental cultures showing a faster doubling for the period T0÷T5. The increase in pH drives the increase in growth in the experimental conditions in which the salt was added. The results suggest that bicarbonate is able to promote the algal growth, therefore it can
be considered a valid alternative to CO2 gas
Potential harm caused by physicians' a-priori beliefs in the clinical effectiveness of hydroxychloroquine and its impact on clinical and economic outcome - A simulation approach
BACKGROUND: Despite growing controversies around Hydroxychloroquine's effectiveness, the drug is still widely prescribed by clinicians to treat COVID19 patients. Therapeutic judgment under uncertainty and imperfect information may be influenced by personal preference, whereby individuals, to confirm a-priori beliefs, may propose drugs without knowing the clinical benefit. To estimate this disconnect between available evidence and prescribing behavior, we created a Bayesian model analyzing a-priori optimistic belief of physicians in Hydroxychloroquine's effectiveness. METHODOLOGY: We created a Bayesian model to simulate the impact of different a-priori beliefs related to Hydroxychloroquine's effectiveness on clinical and economic outcome. RESULTS: Our hypothetical results indicate no significant difference in treatment effect (combined survival benefit and harm) up to a presumed drug's effectiveness level of 20%, with younger individuals being negatively affected by the treatment (RR 0.82, 0.55-1.2; (0.95 (1.1) % expected adverse events versus 0.05 (0.98) % expected death prevented). Simulated cost data indicate overall hospital cost (medicine, hospital stay, complication) of 18.361,41€ per hospitalized patient receiving Hydroxychloroquine treatment. CONCLUSION: Off-label use of Hydroxychloroquine needs a rational, objective and datadriven evaluation, as personal preferences may be flawed and cause harm to patients and to society
Risk factors for recurrence in patients with Clostridium difficile infection due to 027 and non-027 ribotypes
Objectives: Our objective was to evaluate factors associated with recurrence in patients with 027+ and 027– Clostridium difficile infection (CDI). Methods: Patients with CDI observed between January and December 2014 in six hospitals were consecutively included in the study. The 027 ribotype was deduced by the presence of tcdB, tcdB, cdt genes and the deletion Δ117 in tcdC (Xpert® C. difficile/Epi). Recurrence was defined as a positive laboratory test result for C. difficile more than 14 days but within 8 weeks after the initial diagnosis date with reappearance of symptoms. To identify factors associated with recurrence in 027+ and 027– CDI, a multivariate analysis was performed in each patient group. Subdistributional hazard ratios (sHRs) and 95% confidence intervals (95%CIs) were calculated. Results: Overall, 238 patients with 027+ CDI and 267 with 027– CDI were analysed. On multivariate analysis metronidazole monotherapy (sHR 2.380, 95%CI 1.549–3.60, p <0.001) and immunosuppressive treatment (sHR 3.116, 95%CI 1.906–5.090, p <0.001) were factors associated with recurrence in patients with 027+ CDI. In this patient group, metronidazole monotherapy was independently associated with recurrence in both mild/moderate (sHR 1.894, 95%CI 1.051–3.410, p 0.033) and severe CDI (sHR 2.476, 95%CI 1.281–4.790, p 0.007). Conversely, non-severe disease (sHR 3.704, 95%CI 1.437–9.524, p 0.007) and absence of chronic renal failure (sHR 16.129, 95%CI 2.155–125.000, p 0.007) were associated with recurrence in 027– CDI. Conclusions: Compared to vancomycin, metronidazole monotherapy appears less effective in curing CDI without relapse in the 027+ patient group, independently of disease severity
Simultaneous biochemical and physiological responses of the roots and leaves of pancratium maritimum (Amaryllidaceae) to mild salt stress
Pancratium maritimum (Amaryllidaceae) is a bulbous geophyte growing on coastal sands. In this study, we investigated changes in concentrations of metabolites in the root and leaf tissue of P. maritimum in response to mild salt stress. Changes in concentrations of osmolytes, glutathione, sodium, mineral nutrients, enzymes, and other compounds in the leaves and roots were measured at 0, 3, and 10 days during a 10‐day exposure to two levels of mild salt stress, 50 mM NaCl or 100 mM NaCl in sandy soil from where the plants were collected in dunes near Cuma, Italy. Sodium accumulated in the roots, and relatively little was translocated to the leaves. At both concentrations of NaCl, higher values of the concentrations of oxidized glutathione disulfide (GSSG), compared to reduced glutathione (GSH), in roots and leaves were associated with salt tolerance. The concentration of proline increased more in the leaves than in the roots, and glycine betaine increased in both roots and leaves. Differences in the accumulation of organic osmolytes and electron donors synthesized in both leaves and roots demonstrate that osmoregulatory and electrical responses occur in these organs of P. maritimum under mild salt stress
Impact of sulfur starvation in autotrophic and heterotrophic cultures of the Extremophilic Microalga Galdieria Phlegrea (Cyanidiophyceae)
In plants and algae, sulfate assimilation and cysteine synthesis are regulated by sulfur (S) accessibility from the environment. This study reports the effects of S deprivation in autotrophic and heterotrophic cultures of Galdieria phlegrea (Cyanidiophyceae), a unicellular red alga isolated in the Solfatara crater located in Campi Flegrei (Naples, Italy), where H2S is the prevalent form of gaseous S in the fumarolic fluids and S is widespread in the soils near the fumaroles. This is the first report on the effects of S deprivation on a sulfurous microalga that is also able to grow heterotrophically in the dark. The removal of S from the culture medium of illuminated cells caused a decrease in the soluble protein content and a significant decrease in the intracellular levels of glutathione. Cells from heterotrophic cultures of G. phlegrea exhibited high levels of internal proteins and high glutathione content, which did not diminish during S starvation, but rather glutathione significantly increased. The activity of O-acetylserine(thiol)lyase (OASTL), the enzyme synthesizing cysteine, was enhanced under S deprivation in a time-dependent manner in autotrophic but not in heterotrophic cells. Analysis of the transcript abundance of the OASTL gene supports the OASTL activity increase in autotrophic cultures under S deprivation
A parametric study of a multiphase porous media model for tumor spheroids and environment interactions
Computational models for tumor growth provide an effective in silico tool to investigate the different stages of cancer growth. Recently, a series of computational models based on porous media theory has been proposed to predict tumor evolution and its interactions with the host tissue. In addition, a specialization of the original models, adapted for tumor spheroids, has been proposed and validated experimentally. However, due to the complexity of the modeling framework, a systematic understanding of the role of the parameters governing the equations is still lacking. In this work, we perform a parametric analysis on a set of fundamental parameters appearing in the model equations. We investigate the effects of a variation of these coefficients on the spheroid growth curves and, in particular, on the final radii reached by the cell aggregates in the growth saturation stage. Finally, we provide a discussion of the results and give a brief summary of our findings
Aggiornamenti e novità sulle conoscenze di Pancratium maritimum (Amaryllidaceae)
Pancratium maritimum L., bulbosa perenne degli ambienti dunali costieri, è un taxon relativamente recente se comparato con le specie del genere a gravitazione mediterranea. Gli studi noti su questa specie hanno analizzato vari aspetti della biologia (riproduttivi, biochimici, filogenetici, genetici, ecc.). Tuttavia, esistono ancora lacune scientifiche, tra cui l’assenza di studi su ampio areale di genetica di conservazione e sugli adattamenti eco-morfofisiologici alle condizioni di stress.
Per ampliare le conoscenze su P. maritimum, la Fondazione Nando Peretti nel novembre 2012 ha finanziato un progetto triennale sulla conoscenza e la salvaguardia di questa specie (Progetto 2012-83). In questo contributo si presentano i risultati ottenuti per le diverse linee di ricerca finora affrontate, che vanno dalle analisi ad ampio areale dei popolamenti, usando un approccio sia genetico che GIS, alla caratterizzazione morfologica e eco-fisiologica di varie popolazioni
Smart Dairy Farming: Innovative Solutions to Improve Herd Productivity
Among the most straining trends that farmers have to face there are: on one side, to guarantee welfare and adequate life conditions for animals and to reduce the environmental footprint, on the other side, to develop new strategies to improve farm management reducing costs. The current conditions and the expected developments of the dairy sector highlight a strong need for more efficient and sustainable farming systems. Studying heat stress, herd management and housing and animals\u2019 productive and reproductive performances is fundamental for the economic and environmental sustainability of the dairy chain. New and effective tools to cope with these challenges have been provided by Precision Livestock Farming (PLF), which is nowadays increasingly applied and makes possible to control quali-quantitative parameters related to production, health, behaviour, and real-time locomotion per animal. The research key challenge is to turn these data into knowledge to provide real-time support in farming optimisation. This research focuses specifically on different systems to collect, process and derive useful information from data on animal welfare and productivity. A multi-disciplinary approach has been adopted to generate a decision support system for farmers
Salmonella enterica ssp. arizonae infection in a 43-year-old Italian man with hypoglobulinemia: a case report and review of the literature
<p>Abstract</p> <p>Introduction</p> <p><it>Salmonella enterica </it>ssp. <it>arizonae </it>is an uncommon human pathogen with serious infections reported in immunocompromised hosts. In Europe, only a few cases have been described. Patients with this infection usually have a history of contact with reptiles or travel abroad. We present a case report of infection in a patient with hypoglobulinemia and a literature review.</p> <p>Case presentation</p> <p>We describe the case of a 43-year-old Caucasian Italian man with hypoglobulinemia who presented to our hospital with sepsis and diarrhea. A stool culture yielded <it>S. enterica </it>ssp. <it>arizonae</it>. Our patient was treated with oral ciprofloxacin and made a full recovery. We also present a review of the cases of <it>S. enterica </it>ssp. <it>arizonae </it>infections previously reported in Europe.</p> <p>Conclusions</p> <p>The majority of infections from <it>S. enterica </it>ssp. <it>arizonae </it>occur in patients who are immunocompromised. Data from the literature suggests that it may be difficult to eradicate the bacteria and thus, prolonged antibiotic courses are often used. It would be advisable for clinicians to investigate for pre-existing immune dysfunction if <it>S. enterica </it>ssp. <it>arizonae </it>is isolated. In Italy, although there have only been a few cases, the likely route of transmission remains unclear and requires further surveillance.</p
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