An EORTC Phase II study of caspofungin as first-line therapy of invasive aspergillosis in haematological patients

Objectives Caspofungin was evaluated as first-line monotherapy of invasive aspergillosis (IA) in patients with haematological malignancies and undergoing autologous transplants. Methods Adults with proven or probable IA, defined strictly according to EORTC-MSG criteria, were eligible. Those with possible IA were enrolled, but were not evaluable for efficacy unless upgraded to proven/probable disease within 7 days of registration based on investigations performed within 48 h after enrolment. Caspofungin dosage was 70 mg (day 1) followed by 50 mg/day. The primary endpoint was the proportion of patients with complete or partial response at the end of caspofungin therapy in the modified intention to treat (MITT) group; secondary endpoints were response and survival at day 84 and safety. Results In the MITT group (n = 61), 75% of patients had cancer not in remission (relapsing or refractory), 85% were neutropenic at enrolment and 49% had a Karnofsky score of ≤50. At end of treatment, 1 and 19 patients had complete and partial response, respectively [success rate 33% (20/61)], 9 (15%) achieved stabilization and 31 (51%) had disease progression. One patient was not evaluable. The 6 and 12 week survival rates were 66% (40/61) and 53% (32/60), respectively. Baseline characteristics associated with survival at day 84 were an underlying disease in remission (not relapsing or refractory) and Karnofsky score. Recovery from neutropenia at the end of treatment was also significantly associated with survival. No serious drug-related adverse events or discontinuations due to drug-related adverse events were observed. Conclusions Caspofungin provided an observed response rate compatible with the null hypothesis of a true response rate of ≤35%. Underlying disease-related factors had a major impact on result

One year after on Tyrrhenian coasts: The ban of cotton buds does not reduce their dominance in beach litter composition

In January 2019, Italy banned the sale of plastic cotton buds, which is one of the most abundant litter items entering the sea and then washing ashore. However, since the ban came into force, no studies have been carried out to assess whether the measure has actually led to the reduction of plastic cotton buds accumulating on Italian coasts. Here we aim at evaluating the effectiveness of the ban in reducing the amount of cotton buds reaching sandy beaches of the Tyrrhenian coast. Specifically, we monitored the accumulation of beach litter for one year since the ban came into force. By surveying eight coastal sites from winter 2019 to winter 2020, we collected a total of 52,824 items mostly constituted by plastic debris (97.6%). We found that cotton buds were the most abundant item (42.3% of total litter), followed by plastic (28.5%) and polystyrene (5.43%) fragments. Our preliminary assessment suggests that the ban has so far not led to a sensible reduction in the amount of cotton buds entering the marine ecosystem. This was to be expected since implementation strategies are still lacking (i.e. no economic sanctions can be imposed in case of non-compliance) and bans are differently implemented among countries facing the Mediterranean Sea, calling for law enforcement and implementation at the national and international levels

An observational efficacy and safety analysis of the treatment of acute invasive aspergillosis using voriconazole

The purpose of this study was to evaluate efficacy and safety of voriconazole in patients with acute invasive aspergillosis (IA) in a real-life, clinical setting. This was a multicenter observational study in adult patients treated with voriconazole for invasive mycosis. The study evaluated clinical response, mortality, use of other licensed antifungal therapy (OLAT), and treatment duration. This sub-analysis evaluated treatment and outcome data specifically from adult patients with proven/probable IA, while safety data were assessed in patients with proven/probable/possible IA. Of the 141 patients enrolled, 113 were adults with proven/probable IA and six had possible IA. Voriconazole treatment duration ranged from 1 to 183 days (median, 49.5 days). Voriconazole was used exclusively in 64% (72/113) of patients and in combination/sequentially with OLAT in 36%. Overall successful treatment response was 50% (57/113 patients). Twelve percent (14/113) of patients were switched to OLAT, either because of insufficient response (four patients) or for safety reasons (10 patients). Overall and attributable (entirely or partially due to fungal infection) mortality rates were 52% (59/113) and 17%, respectively. Treatment-related adverse events were reported for 18% (22/119) of patients. This observational study confirms the results of previous clinical trials demonstrating voriconazole as an effective and safe agent for treatment of confirmed acute IA

Modern wolves trace their origin to a late Pleistocene expansion from Beringia

Grey wolves (Canis lupus) are one of the few large terrestrial carnivores that maintained a wide geographic distribution across the Northern Hemisphere throughout the Pleistocene and Holocene. Recent genetic studies have suggested that, despite this continuous presence, major demographic changes occurred in wolf populations between the late Pleistocene and early Holocene, and that extant wolves trace their ancestry to a single late Pleistocene population. Both the geographic origin of this ancestral population and how it became widespread remain a mystery. Here we analyzed a large dataset of novel modern and ancient mitochondrial wolf genomes, spanning the last 50,000 years, using a spatially and temporally explicit modeling framework to show that contemporary wolf populations across the globe trace their ancestry to an expansion from Beringia at the end of the Last Glacial Maximum - a process most likely driven by the significant ecological changes that occurred across the Northern Hemisphere during this period. This study provides direct ancient genetic evidence that long-range migration has played an important role in the population history of a large carnivore and provides an insight into how wolves survived the wave of megafaunal extinctions at the end of the last glaciation. Moreover, because late Pleistocene grey wolves were the likely source from which all modern dogs trace their origins, the demographic history described in this study has fundamental implications for understanding the geographical origin of the dog

How Molecular Evolution Technologies can Provide Bespoke Industrial Enzymes: Application to Biofuels Comment les technologies d’évolution moléculaire peuvent fournir des enzymes industrielles sur mesure : application aux biocarburants

Enzymatic hydrolysis of lignocellulose is one of the major bottlenecks in the development of biological conversion of lignocellulosic biomass to biofuels. One of the most efficient organisms for the production of cellulolytic enzymes is the fungus Trichoderma reesei, mainly thanks to its high secretion capacity. The conversion of cellulose to glucose involves three types of cellulases working in synergy: endoglucanases (EC 3.2.1.4) randomly cleave 13-1,4 glycosidic linkages of cellulose, cellobiohydrolases (EC 3.2.1.91) attack cellulose chain ends to produce cellobiose dimers which are converted into glucose by the 13-glucosidases (EC 3.2.1 21). Unexpectedly, the amount of l3-glucosidase (BGLI) from T. reesei hyperproducing strains represents a very low percentage of the total secreted proteins. A suboptimal content of this enzyme limits the performance of commercial cellulase preparations as cellobiose represents the main inhibitor of the cellulolysis reaction by cellobiohydrolases. This bottleneck can be alleviated either by overexpressing the f3-glucosidase in T. reesei or optimized its specific activity. After giving a brief overview of the main available technologies, this example will be used to illustrate the potential of directed evolution technologies to devolop enzymes tailored to fit industrial needs. We describe the L-ShuffiingTM strategy implemented with three parental genes originating from microbial biodiversity leading to identification of an efficient 13-glucosidase showing a 242 fold increase in specific activity for the pNPGIc substrate compared to WT (Wild Type) Cel3a beta-glucosidase of T. reesei. After expression of the best improved 13-glucosidase in T. reesei and secretion of a new enzymatic cocktail, improvement of the glucosidase activity allows a 4-fold decrease of cellulase loading for the saccharification of an industrial pretreated biomass compared to the parental cocktail. L’hydrolyse enzymatique de la lignocellulose est l’un des principaux goulets d’étranglement dans le développement de la conversion biologique de la biomasse lignocellulosique en biocarburants. L’un des organismes les plus efficaces pour la production d’enzymes cellulolytiques est le champignon Trichoderma reesei, principalement grâce à sa capacité importante de sécrétion. La conversion de la cellulose en glucose implique trois types de cellulases travaillant en synergie : les endoglucanases (EC 3.2.1.4) clivant de façon aléatoire les liaisons glycosidiques en (3-1,4, les cellobiohydrolases (EC 3.2.1.91) attaquant la chaîne de cellulose aux deux extrémités afin de produire le cellobiose, dimère qui sera converti en glucose par l’action des (3-glucosidases (EC 3.2.1.21). De façon inattendue, la quantité de 3-glucosidase (BGL1) sécrétée par les souches de T. reesei représente un très faible pourcentage de la quantité totale des protéines sécrétées qui en fait donc une activité limitante du cocktail. Cette faible activité limite d’autant plus les performances du cocktail que le cellobiose représente le principal inhibiteur de la réaction cellulolyse par les cellobiohydrolases. Ce goulot d’étranglement peut être atténué soit par une surexpression de la (3-glucosidase chez T. reesei, soit par une amélioration de son activité spécifique. Après un bref aperçu des principales technologies existantes, cet exemple sera utilisé dans cette revue pour illustrer le potentiel des technologies d’évolution dirigée pour développer des enzymes répondant aux besoins de l’industrie des biotechnologies. Nous décrivons comment la mise en oeuvre d’une stratégie d’évolution dirigée par le L-ShufflingTM avec trois gènes parentaux provenant de la biodiversité microbienne permet d’obtenir des activités (3-glucosidases très améliorées par rapport à la Cel3a (3-glucosidase de T. reesei (activité spécifique 242 fois plus élevée pour le substrat pNPGIc). Cette amélioration de l’activité glucosidasique, après expression du gène codant pour la 3-glucosidase améliorée chez T. reesei et sécrétion du nouveau cocktail, permet une diminution d’un facteur 4 de la quantité de cocktail nécessaire à la saccharification d’une biomasse industrielle prétraitée (paille de blé)

How Molecular Evolution Technologies can Provide Bespoke Industrial Enzymes: Application to Biofuels

Enzymatic hydrolysis of lignocellulose is one of the major bottlenecks in the development of biological conversion of lignocellulosic biomass to biofuels. One of the most efficient organisms for the production of cellulolytic enzymes is the fungus Trichoderma reesei, mainly thanks to its high secretion capacity. The conversion of cellulose to glucose involves three types of cellulases working in synergy: endoglucanases (EC 3.2.1.4) randomly cleave 13-1,4 glycosidic linkages of cellulose, cellobiohydrolases (EC 3.2.1.91) attack cellulose chain ends to produce cellobiose dimers which are converted into glucose by the 13-glucosidases (EC 3.2.1 21). Unexpectedly, the amount of l3-glucosidase (BGLI) from T. reesei hyperproducing strains represents a very low percentage of the total secreted proteins. A suboptimal content of this enzyme limits the performance of commercial cellulase preparations as cellobiose represents the main inhibitor of the cellulolysis reaction by cellobiohydrolases. This bottleneck can be alleviated either by overexpressing the f3-glucosidase in T. reesei or optimized its specific activity. After giving a brief overview of the main available technologies, this example will be used to illustrate the potential of directed evolution technologies to devolop enzymes tailored to fit industrial needs. We describe the L-ShuffiingTM strategy implemented with three parental genes originating from microbial biodiversity leading to identification of an efficient 13-glucosidase showing a 242 fold increase in specific activity for the pNPGIc substrate compared to WT (Wild Type) Cel3a beta-glucosidase of T. reesei. After expression of the best improved 13-glucosidase in T. reesei and secretion of a new enzymatic cocktail, improvement of the glucosidase activity allows a 4-fold decrease of cellulase loading for the saccharification of an industrial pretreated biomass compared to the parental cocktail

How Molecular Evolution Technologies can Provide Bespoke Industrial Enzymes: Application to Biofuels

International audienceEnzymatic hydrolysis of lignocellulose is one of the major bottlenecks in the development of biological conversion of lignocellulosic biomass to biofuels. One of the most efficient organisms for the production of cellulolytic enzymes is the fungus Trichoderma reesei, mainly thanks to its high secretion capacity. The conversion of cellulose to glucose involves three types of cellulases working in synergy: endoglucanases (EC 3.2.1.4) randomly cleave b-1,4 glycosidic linkages of cellulose, cellobiohydrolases (EC 3.2.1.91) attack cellulose chain ends to produce cellobiose dimers which are converted into glucose by the b-glucosidases (EC 3.2.1 21). Unexpectedly, the amount of b-glucosidase (BGL1) from T. reesei hyperproducing strains represents a very low percentage of the total secreted proteins. A suboptimal content of this enzyme limits the performance of commercial cellulase preparations as cellobiose represents the main inhibitor of the cellulolysis reaction by cellobiohydrolases. This bottleneck can be alleviated either by overexpressing the b-glucosidase in T. reesei or optimized its specific activity. After giving a brief overview of the main available technologies, this example will be used to illustrate the potential of directed evolution technologies to devolop enzymes tailored to fit industrial needs. We describe the L-ShufflingTM strategy implemented with three parental genes originating from microbial biodiversity leading to identification of an efficient b-glucosidase showing a 242-fold increase in specific activity for the pNPGlc substrate compared to WT (Wild Type) Cel3a beta-glucosidase of T. reesei. After expression of the best improved b-glucosidase in T. reesei and secretion of a new enzymatic cocktail, improvement of the glucosidase activity allows a 4-fold decrease of cellulase loading for the saccharification of an industrial pretreated biomass compared to the parental cocktail