Callus culture for biomass production of milk thistle as a potential source of milk clotting peptidases

The objective of this work was the optimization of the conditions of in vitro culture for callus production of Silybum marianum (L.) Gaertn. (Asteraceae). Sections of cotyledons, previously disinfected by washing successively with ethanol 70º, NaClO (10% w/v) and Tween 20 (0.05% v/v) and rinsing with sterile distilled water, were used as explants. For its initial culture, B5 medium supplemented with BA and 2,4-D solidified with phytagel was used, and a 63% survival was achieved. To obtain callus, two solid media were assayed (S1 and S2) using B5 medium supplemented with growth regulators (BA and 2,4-D or NAA and BA, respectively). The calli were grown at 25ºC during 45 days in darkness. Growth kinetics was studied using S1 medium obtaining a typical growth curve with an exponential phase after 14 days of incubation (rate of growth 0.005 g dry weight/ day) and stationary phase after 35 days. The rate of growth in S2 medium was slower, and rhizogenesis was observed starting on the fifth week of incubation. From these results, the best culture medium for callus production of Silybum marianum was S1 medium.Facultad de Ciencias Exacta

Callus culture for biomass production of milk thistle as a potential source of milk clotting peptidases

The objective of this work was the optimization of the conditions of in vitro culture for callus production of Silybum marianum (L.) Gaertn. (Asteraceae). Sections of cotyledons, previously disinfected by washing successively with ethanol 70º, NaClO (10% w/v) and Tween 20 (0.05% v/v) and rinsing with sterile distilled water, were used as explants. For its initial culture, B5 medium supplemented with BA and 2,4-D solidified with phytagel was used, and a 63% survival was achieved. To obtain callus, two solid media were assayed (S1 and S2) using B5 medium supplemented with growth regulators (BA and 2,4-D or NAA and BA, respectively). The calli were grown at 25ºC during 45 days in darkness. Growth kinetics was studied using S1 medium obtaining a typical growth curve with an exponential phase after 14 days of incubation (rate of growth 0.005 g dry weight/ day) and stationary phase after 35 days. The rate of growth in S2 medium was slower, and rhizogenesis was observed starting on the fifth week of incubation. From these results, the best culture medium for callus production of Silybum marianum was S1 medium.Facultad de Ciencias Exacta

Callus culture for biomass production of milk thistle as a potential source of milk clotting peptidases

The objective of this work was the optimization of the conditions of in vitro culture for callus production of Silybum marianum (L.) Gaertn. ( Asteraceae) . Sections of cotyledons, previously disinfected by washing successively with ethanol 70\ub0, NaClO (10% w/v) and Tween 20 (0.05% v/v) and rinsing with sterile distilled water, were used as explants. For its initial culture, B5 medium supplemented with BA and 2,4-D solidified with phytagel was used, and a 63% survival was achieved. To obtain callus, two solid media were assayed (S1 and S2) using B5 medium supplemented with growth regulators (BA and 2,4-D or NAA and BA, respectively). The calli were grown at 25\ub0C during 45 days in darkness. Growth kinetics was studied using S1 medium obtaining a typical growth curve with an exponential phase after 14 days of incubation (rate of growth 0.005 g dry weight/ day) and stationary phase after 35 days. The rate of growth in S2 medium was slower, and rhizogenesis was observed starting on the fifth week of incubation. From these results, the best culture medium for callus production of Silybum marianum was S1 medium

Callus culture for biomass production of milk thistle as a potential source of milk clotting peptidases

The objective of this work was the optimization of the conditions of in vitro culture for callus production of Silybum marianum (L.) Gaertn. ( Asteraceae ). Sections of cotyledons, previously disinfected by washing successively with ethanol 70\ub0, NaClO (10% w/v) and Tween 20 (0.05% v/v) and rinsing with sterile distilled water, were used as explants. For its initial culture, B5 medium supplemented with BA and 2,4-D solidified with phytagel was used, and a 63% survival was achieved. To obtain callus, two solid media were assayed (S1 and S2) using B5 medium supplemented with growth regulators (BA and 2,4-D or NAA and BA, respectively). The calli were grown at 25\ub0C during 45 days in darkness. Growth kinetics was studied using S1 medium obtaining a typical growth curve with an exponential phase after 14 days of incubation (rate of growth 0.005 gdry weight/ day) and stationary phase after 35 days. The rate of growth in S2 medium was slower, and rhizogenesis was observed starting on the fifth week of incubation. From these results, the best culture medium for callus production of Silybum marianum was S1 medium

Extraction and partial characterization of a coagulant preparation from Silybum marianum flowers: its action on bovine caseinate

An outstanding parameter in cheese making is the type of coagulant, which greatly influences the characteristics of the final products. Proteolysis is the most important set of biochemical changes during ripening of most cheeses, and is carried out, in different magnitude, by proteolytic agents originated in milk, rennet (or rennet substitute), and starter and non-starter micro-organisms (Silva & Malcata, 2000). The demand for alternative sources of milk coagulants, to replace the expensive and limited natural rennet supplies, has increased (Esteves et al. 2001). All commercial enzymes employed as milk coagulant are aspartic proteinases, which are most active at acidic pH and preferentially cleave peptide bonds between residues with hydrophobic side-chains (Silva & Malcata, 1999). Because of the presence of aspartic proteinases, aqueous crude extracts from flowers of Cynara cardunculus (Verı´ssimo et al. 1995, 1996), Cynara humilis, and/or Cynara scolymus are traditionally employed in the Iberian Peninsula as vegetable rennet for cheesemaking (Reis et al. 2000). Milk clotting activity was also proved in flowers of Centaurea calcitrapa and Onopordum turcicum (Tamer, 1993; Domingos et al. 1998). All these species are included within the Asteraceae family and furthermore in the same tribe : Cardueae Cass.=Cynareae Less. (Ariza Espinar & Delucchi, 1998). When a potential rennet substitute is studied, it is particularly important to evaluate adequately the degradation patterns of the caseins because of their effects on yield, consistency, and flavour of the final cheese (Fox, 1989). It is important to guarantee a well-balanced breakdown of curd proteins (caseins) in order to avoid formation of undesired attributes in cheese such as low viscosity and high bitterness (Visser, 1993). One of the most frequently used methods to monitor proteolytic processes on caseins is urea-polyacrylamide gel electrophoresis. On the other hand, tricine-SDS polyacrylamide gel electrophoresis improves the separation, identification and quantification of casein hydrolysates because it allows the visualization of large and small peptides (Pardo & Natalucci, 2001), with the additional advantage of allowing the estimation of molecular masses. Both methods are then suitable to characterize the performance of vegetable rennet in different ways. This preliminary study had the following objectives: the partial characterization of (i) the aspartic proteolytic activity present in flowers of Silybum marianum (L.) Gaertn. (Asteraceae) ; and (ii) the hydrolytic profile of bovine caseins.Centro de Investigación de Proteínas Vegetale

household transmission and disease transmissibility of a large hav outbreak in lazio italy 2016 2017

Abstract A major outbreak of Hepatitis A Virus (HAV) has swept through Europe between mid-2016 and 2017, mainly within the community of men who have sex with men (MSM). Over the same period, about 1,000 outbreak-related cases of acute Hepatitis A (AHA) were recorded in Lazio region, Italy. We calibrated a Bayesian model to reconstruct likely transmission events within all 44 households where multiple infections were recorded, representing a total of 103 cases from the HAV outbreak in Lazio. Based on information on the observed times of symptom onset, we estimated for the probability distribution function of the HAV generation time and used it to compute the effective and instantaneous reproduction numbers for the considered outbreak from the overall epidemic curve (N = 998 cases). We estimated a mean generation time of 30.2 days (95%CI: 25.2-33.0) and an effective reproduction number of about 1.63 (95% CI: 1.35-1.94). Transmissibility peaked in January 2017, shortly before targeted awareness and vaccination campaigns were put in place by health authorities; however, transmission remained above the epidemic threshold until June 2017. Within households, children (0-15) and young adults (16-30) infected preferentially individuals of the same age class, whereas transmission within older age groups was substantially homogeneous. These results suggest that the implemented interventions were able to slow down HAV transmission, but not to bring it rapidly to a halt. According to our estimates of the HAV transmissibility, about 50% of the at-risk persons should be immunized to prevent similar outbreaks in the future. Our results also indicate spillover from community transmission to household members, suggesting the opportunity of vaccinating household contacts of cases to prevent further spread of the epidemics

Secondary Autochthonous Outbreak of Chikungunya, Southern Italy, 2017

In 2017, a chikungunya outbreak in central Italy later evolved into a secondary cluster in southern Italy, providing evidence of disease emergence in new areas. Officials have taken action to raise awareness among clinicians and the general population, increase timely case detection, reduce mosquito breeding sites, and promote mosquito bite prevention

Acute Delta Hepatitis in Italy spanning three decades (1991–2019): Evidence for the effectiveness of the hepatitis B vaccination campaign

Updated incidence data of acute Delta virus hepatitis (HDV) are lacking worldwide. Our aim was to evaluate incidence of and risk factors for acute HDV in Italy after the introduction of the compulsory vaccination against hepatitis B virus (HBV) in 1991. Data were obtained from the National Surveillance System of acute viral hepatitis (SEIEVA). Independent predictors of HDV were assessed by logistic-regression analysis. The incidence of acute HDV per 1-million population declined from 3.2 cases in 1987 to 0.04 in 2019, parallel to that of acute HBV per 100,000 from 10.0 to 0.39 cases during the same period. The median age of cases increased from 27 years in the decade 1991-1999 to 44 years in the decade 2010-2019 (p < .001). Over the same period, the male/female ratio decreased from 3.8 to 2.1, the proportion of coinfections increased from 55% to 75% (p = .003) and that of HBsAg positive acute hepatitis tested for by IgM anti-HDV linearly decreased from 50.1% to 34.1% (p < .001). People born abroad accounted for 24.6% of cases in 2004-2010 and 32.1% in 2011-2019. In the period 2010-2019, risky sexual behaviour (O.R. 4.2; 95%CI: 1.4-12.8) was the sole independent predictor of acute HDV; conversely intravenous drug use was no longer associated (O.R. 1.25; 95%CI: 0.15-10.22) with this. In conclusion, HBV vaccination was an effective measure to control acute HDV. Intravenous drug use is no longer an efficient mode of HDV spread. Testing for IgM-anti HDV is a grey area requiring alert. Acute HDV in foreigners should be monitored in the years to come

Antibiotic-loaded nanstructured lipid carriers (NLCs) for multiresistant respiratory tract and wound infections.

172 p.La resistencia a los antibióticos (AMR) es un problema grave que debe abordarse lo antes posible. La colistina y la amikacina representan unos de los pocos antibióticos eficaces contra las infecciones de las bacterias gran-negativas multirresistentes, pero son altamente neuro y nefrotóxicos. De hecho, los médicos se ven obligados a elegir entre una dosis efectiva o segura, lo cual conduce mayoritariamente al fracaso del tratamiento. Teniendo eso en cuenta, los transportadores lipídicos nanoestructurados (NLCs) representan una estrategia cautivadora para reducir la toxicidad del fármaco, capaz de liberar antibióticos de manera sostenida y permitir la reducción de la dosis. En esta tesis doctoral, se han desarrollado, caracterizado y analizado las NLCs cargadas con colistina en modelos de neumonía en ratones con resultados prometedores, logrando una reducción significativa de la dosis, una mayor eficacia y una posible reducción de la toxicidad. Además, se probó la seguridad de la NLCs vacías aplicada tópicamente en piel intacta y dañada. Las NLCs resultaron ser seguras y podrían ejercer un efecto local sobre las heridas infectadas, lo cual representa una gran oportunidad a explotar en un futuro cercano. En esencia, los NLC podrían ser la más segura estrategia para el suministro de antibióticos en infecciones multiresistentes del tracto respiratorios y de heridas.Biokeralty; NanoBioCe