ASSESSMENT OF KINETICS FOR BUTANOL PRODUCTION BY CLOSTRIDIUM ACETOBUTYLICUM

The economic scenario established at the beginning of the third millennium has revived the interest in Acetone-Butanol-Ethanol (ABE) fermentations. Recent developments in molecular techniques applied to solventogenic microrganisms in combination with recent advances in fermentation systems and downstream processing have contributed to improve ABE fermentation processes feasibility and competitiveness. The challenges raised over the last years as regards ABE production may be synthesized in: i) use of renewable resources as substrate; ii) selection of strains characterized by high ABE productivity; iii) development of new fermentation systems; iv) development of new downstream strategies for enhanced solvent recovery. The selection of unconventional substrates is favoured by the ability of clostridia strains to metabolize a wide range of carbohydrates like glucose, lactose, etc...., typically present in wastewater streams e.g. from food industries. Even though clostridia have been proven successful to produce ABE, information about kinetics of substrate conversion, cell growth and butanol production is still lacking. Studies available in literature most typically regard batch tests whose results do not apply easily to continuous processes. The strong interaction between the growth/acidogenesis phase and the solventogenesis phase should be taken into account. The reactor systems investigated for the ABE fermentation belong to the batch and fed-batch typologies. Some attempts are reported in literature regarding continuous fermentation by means of clostridia strains confined in the reactor by immobilization or cell-recycling. The present study reports the preliminary results of a research activity aiming at investigating the feasibility of the ABE production by Clostridium acetobutylicum ATCC824 in a continuous biofilm reactor adopting cheese whey as feedstock. The contribution regards the characterization of the kinetics related to the ABE production process by free C. acetobutylicum ATCC824 adopting as medium lactose solutions, in order to emulate the cheese whey. The conversion process is characterized in terms of cells, acids, solvents, pH, gas composition and total organic compounds as a function of time. Results are worked out to assess the kinetics of the cells growth and of the ABE production. The yields of the carbon source in cells, acids and solvents are also assessed. The investigation is carried out adopting both batch reactors and two continuous reactors. In particular, the continuous reactors are equipped to operate under controlled conversion regimes, acidogenesis or solventogenesis. Tests carried out under batch conditions show that: i) cells growth follows the Monod kinetics for lactose concentration (CL) smaller than 100 g/L; ii) the butanol specific production rate increases linearly with CL; iii) the lactose conversion - measured at the end of the solventogenesis phase - decreases with CL; iv) the selectivity of butanol with respect to total solvents increases with CL and stabilizes at about 72%W for CL larger than 30 g/L. Preliminary tests carried out with the continuous reactor operated under solventogenesis regime show that steady state establishes with respect to cells and metabolites concentration at dilution rate of about 0.04 h-1

High Granularity approaches for effective energy delivery from Photovoltaic Sources

Silicon solar cell technology is a fully mature technology but the need to compete with traditional and other renewable energy sources urges to improve the overall efficiency of a photovoltaic (PV) system by a significant amount. Regardless of the solar panel efficiency, the difference between the nominal performance of a PV system and the energy actually produced is quite high, and it can be quantified in the order of 20%. A loss term, often underestimated, depends on possible failure of the Maximum Power Point Tracking (MPPT) algorithms in the presence of multiple maximum power points in power-voltage characteristic, arising in mismatch conditions. This work proposes High Granularity (HG) approaches in order to improve the PV energy yield: a monitoring strategy, a modeling and a power flux control of the whole PV system, all performed at level of single elementary source (i.e., PV cell or PV panel). An innovative HG sensor infrastructure was developed, and the measurements were exploited to perform an automatic PV system reconfiguration, and to design an information based MPPT. Moreover, the data validated a circuit HG model describing the PV system at single cell level, which also accounts for the electrothermal effect. The model was exploited in an automatic tool which translates an AutoCAD project of a PV plant in an equivalent circuit netlist. Finally, the results were employed to investigate the effectiveness of distributed power conversion – in particular the efficiency of the multilevel cascaded H bridge converter controlled by means of an innovative strategy, which overcomes some issues related to the need of performing a distributed MPPT, was assessed

Accurate Maximum Power Tracking in Photovoltaic Systems Affected by Partial Shading

A maximum power tracking algorithm exploiting operating point information gained on individual solar panels is presented. The proposed algorithm recognizes the presence of multiple local maxima in the power voltage curve of a shaded solar field and evaluates the coordinated of the absolute maximum. The effectiveness of the proposed approach is evidenced by means of circuit level simulation and experimental results. Experiments evidenced that, in comparison with a standard perturb and observe algorithm, we achieve faster convergence in normal operating conditions (when the solar field is uniformly illuminated) and we accurately locate the absolute maximum power point in partial shading conditions, thus avoiding the convergence on local maxima

Synthesis of Oligonucleotide Conjugates and Phosphorylated Nucleotide Analogues: An Improvement to a Solid Phase Synthetic Approach

An improvement to our solid phase strategy to generate pharmacologically interesting molecule libraries is proposed here. The synthesis of newo-chlorophenol-functionalised solid supports with very high loading (0.18–0.22 meq/g for control pore glass (CPG) and 0.25–0.50 meq/g for TG) is reported. To test the efficiency of these supports, we prepared nucleotide and oligonucleotide models, and their coupling yields and the purity of the crude detached materials were comparable to previously available results. These supports allow the facile and high-yield preparation of highly pure phosphodiester and phosphoramidate monoester nucleosides, conjugated oligonucleotides, and other yet unexplored classes of phosphodiester and phosphoramidate molecules

Burden and viral aetiology of influenza-like illness and acute respiratory infection in intensive care units

The purpose of this investigation was to study the viral aetiology of influenza-like illness (ILI) and acute respiratory tract infection (ARTI) among patients requiring intensive care unit admission.A cross-sectional retrospective study was carried out in Sicily over a 4-year period. A total of 233 respiratory samples of patients with ILI/ARTI admitted to intensive care units were molecularly analyzed for the detection of a comprehensive panel of aetiologic agents of viral respiratory infections.About 45% of patients was positive for at least one pathogen. Single aetiology occurred in 75.2% of infected patients, while polymicrobial infection was found in 24.8% of positive subjects. Influenza was the most common aetiologic agent (55.7%), especially among adults. Most of patients with multiple aetiology (76.9%) were adults and elderly. Mortality rates among patients with negative or positive aetiology did not significantly differ (52.4% and 47.6%, respectively).Highly transmissible respiratory pathogens are frequently detected among patients with ILI/ARTI admitted in intensive care units, showing the occurrence of concurrent infections by different viruses. The knowledge of the circulation of several types of microorganisms is of crucial importance in terms of appropriateness of therapies, but also for the implication in prevention strategies and hospital epidemiology

New 23-phosphodiester derivatives of Silibin and DHS: synthesis and preliminary evaluation of antioxidant properties

Silybin is the major flavonolignan of silymarin which is widely used as a natural remedy for the treatment of cirrhosis, chronic hepatitis, and liver diseases associated with alcohol consumption and exposure to environmental toxins. Different studies recently made on the antiradical activity of silybin and DHS have elucidated the functional groups responsible for this activity. The results suggest that the C-23 position could be a site for useful modifications aimed to improve the bioactivity of silybin and/or DHS analogues. Recently we describe an efficient synthetic strategy to obtain a variety of new silybin and 2,3-dehydrosilybin (DHS) derivatives in which the 23-hydroxyl group was converted to a sulfate, phosphodiester, or amine group, using a solution-phase approach. The antioxidant properties of the new compounds were evaluated in a cellular model in vivo and most of them displayed an antioxidant activity comparable or higher to silybin and DHS. These results confirmed the assumption that modifications in position C–23 do not affect the radical scavenging activity of these analogues. With the final goal to expand the repertoire of silybin and DHS C-23 modified, we describe here the synthesis and preliminary evaluation of antioxidant properties of a variety of new silybin and DHS conjugated with different labels through a phosphodiester bond The antioxidative properties of the above-synthesized compounds were determined by free radical scavenging (DPPH) assay

Surgical Treatment of Extravasation Injuries

The authors present their experience of treating anti-cancer drug extravasation by means of a composite surgical technique that consists of infiltration with physiological solution and hyaluronidase and subsequent manual aspiration of solutes alternated with profuse irrigation of the infiltrated area. In the immediate post-op we carry out a medical therapy that consists of calciparine and topic antibiotic and/or steroid creams. Since the year 2000 this technique has been used on 25 patients. We have had neither complications nor scars. Copyright 2005 Wiley-Liss, IncSurgical treatment of extravasation injuries. Napoli P, Corradino B, Badalamenti G, Tripoli M, Vieni S, Furfaro MF, Cordova A, Moschella F. Source Chirurgia Plastica e Ricostruttiva, Dipartimento di Discipline Chirurgiche ed Oncologiche, Università degli Studi di Palermo, Italy. [email protected] Abstract The authors present their experience of treating anti-cancer drug extravasation by means of a composite surgical technique that consists of infiltration with physiological solution and hyaluronidase and subsequent manual aspiration of solutes alternated with profuse irrigation of the infiltrated area. In the immediate post-op we carry out a medical therapy that consists of calciparine and topic antibiotic and/or steroid creams. Since the year 2000 this technique has been used on 25 patients. We have had neither complications nor scars

The Impact of GLP-1 RAs and DPP-4is on Hospitalisation and Mortality in the COVID-19 Era: A Two-Year Observational Study

Novel antidiabetic drugs have the ability to produce anti-inflammatory effects regardless of their glucose-lowering action. For this reason, these molecules (including GLP-1 RAs and DPP-4is) were hypothesized to be effective against COVID-19, which is characterized by cytokines hyperactivity and multiorgan inflammation. The aim of our work is to explore the potential protective role of GLP-1 RAs and DPP-4is in COVID-19 (with the disease intended to be a model of an acute stressor) and non-COVID-19 patients over a two-year observation period. Retrospective and one-versus-one analyses were conducted to assess the impact of antidiabetic drugs on the need for hospitalization (in both COVID-19- and non-COVID-19-related cases), in-hospital mortality, and two-year mortality. Logistic regression analyses were conducted to identify the variables associated with these outcomes. Additionally, log-rank tests were used to plot survival curves for each group of subjects, based on their antidiabetic treatment. The performed analyses revealed that despite similar hospitalization rates, subjects undergoing home therapy with GLP-1 RAs exhibited significantly lower mortality rates, even over a two-year period. These individuals demonstrated improved survival estimates both within hospital and non-hospital settings, even during a longer observation period

Additional modifications to the Blumgart pancreaticojejunostomy: Results of a propensity score-matched analysis versus Cattel-Warren pancreaticojejunostomy

Abstract Background Postoperative pancreatic fistula continues to occur frequently after pancreatoduodenectomy. Methods We have described a modification of the Blumgart pancreaticojejunostomy. The modification of the Blumgart pancreaticojejunostomy was compared to the Cattel-Warren pancreaticojejunostomy in cohorts of patients matched by propensity scores based on factors predictive of clinically relevant postoperative pancreatic fistula, which was the primary endpoint of this study. Based on a noninferiority study design, 95 open pancreatoduodenectomies per group were needed. Feasibility of the modification of the Blumgart pancreaticojejunostomy in robotic pancreatoduodenectomy was also shown. All pancreaticojejunostomies were performed by a single surgeon. Results Between October 2011 and May 2019, there were 415 pancreatoduodenectomies with either a Cattel-Warren pancreaticojejunostomy (n = 225) or a modification of the Blumgart pancreaticojejunostomy (n = 190). There was 1 grade C postoperative pancreatic fistula in 190 consecutive modification of the Blumgart pancreaticojejunostomies (0.5%). Logistic regression analysis showed that the rate of clinically relevant postoperative pancreatic fistula was not affected by consecutive case number. After exclusion of robotic pancreatoduodenectomies (the Cattel-Warren pancreaticojejunostomy: 82; modification of the Blumgart pancreaticojejunostomy: 66), 267 open pancreatoduodenectomies were left, among which the matching process identified 109 pairs. The modification of the Blumgart pancreaticojejunostomy was shown to be noninferior to the Cattel-Warren pancreaticojejunostomy with respect to clinically relevant postoperative pancreatic fistula (11.9% vs 22.9%; odds ratio: 0.46 [0.21–0.93]; P = .03), grade B postoperative pancreatic fistula (11.9% vs 18.3%; P = .18), and grade C postoperative pancreatic fistula (0 vs 4.6%; P = .05) as well as to all secondary study endpoints. The modification of the Blumgart pancreaticojejunostomy was feasible in 66 robotic pancreatoduodenectomies. In this subgroup with 1 conversion to open surgery (1.5%), a clinically relevant postoperative pancreatic fistula occurred after 9 procedures (13.6%) with no case of grade C postoperative pancreatic fistula and a 90-day mortality of 3%. Conclusion The modification of the Blumgart pancreaticojejunostomy described herein is noninferior to the Cattel-Warren pancreaticojejunostomy in open pancreatoduodenectomy. This technique is also feasible in robotic pancreatoduodenectomy