Prospective individual patient data meta-analysis of two randomized trials on convalescent plasma for COVID-19 outpatients

Data on convalescent plasma (CP) treatment in COVID-19 outpatients are scarce. We aimed to assess whether CP administered during the first week of symptoms reduced the disease progression or risk of hospitalization of outpatients. Two multicenter, double-blind randomized trials (NCT04621123, NCT04589949) were merged with data pooling starting when = 50 years and symptomatic for <= 7days were included. The intervention consisted of 200-300mL of CP with a predefined minimum level of antibodies. Primary endpoints were a 5-point disease severity scale and a composite of hospitalization or death by 28 days. Amongst the 797 patients included, 390 received CP and 392 placebo; they had a median age of 58 years, 1 comorbidity, 5 days symptoms and 93% had negative IgG antibody-test. Seventy-four patients were hospitalized, 6 required mechanical ventilation and 3 died. The odds ratio (OR) of CP for improved disease severity scale was 0.936 (credible interval (CI) 0.667-1.311); OR for hospitalization or death was 0.919 (CI 0.592-1.416). CP effect on hospital admission or death was largest in patients with <= 5 days of symptoms (OR 0.658, 95%CI 0.394-1.085). CP did not decrease the time to full symptom resolution

SARS-CoV-2 susceptibility and COVID-19 disease severity are associated with genetic variants affecting gene expression in a variety of tissues

Variability in SARS-CoV-2 susceptibility and COVID-19 disease severity between individuals is partly due to genetic factors. Here, we identify 4 genomic loci with suggestive associations for SARS-CoV-2 susceptibility and 19 for COVID-19 disease severity. Four of these 23 loci likely have an ethnicity-specific component. Genome-wide association study (GWAS) signals in 11 loci colocalize with expression quantitative trait loci (eQTLs) associated with the expression of 20 genes in 62 tissues/cell types (range: 1:43 tissues/gene), including lung, brain, heart, muscle, and skin as well as the digestive system and immune system. We perform genetic fine mapping to compute 99% credible SNP sets, which identify 10 GWAS loci that have eight or fewer SNPs in the credible set, including three loci with one single likely causal SNP. Our study suggests that the diverse symptoms and disease severity of COVID-19 observed between individuals is associated with variants across the genome, affecting gene expression levels in a wide variety of tissue types

Whole-genome sequencing reveals host factors underlying critical COVID-19

Critical COVID-19 is caused by immune-mediated inflammatory lung injury. Host genetic variation influences the development of illness requiring critical care1 or hospitalization2–4 after infection with SARS-CoV-2. The GenOMICC (Genetics of Mortality in Critical Care) study enables the comparison of genomes from individuals who are critically ill with those of population controls to find underlying disease mechanisms. Here we use whole-genome sequencing in 7,491 critically ill individuals compared with 48,400 controls to discover and replicate 23 independent variants that significantly predispose to critical COVID-19. We identify 16 new independent associations, including variants within genes that are involved in interferon signalling (IL10RB and PLSCR1), leucocyte differentiation (BCL11A) and blood-type antigen secretor status (FUT2). Using transcriptome-wide association and colocalization to infer the effect of gene expression on disease severity, we find evidence that implicates multiple genes—including reduced expression of a membrane flippase (ATP11A), and increased expression of a mucin (MUC1)—in critical disease. Mendelian randomization provides evidence in support of causal roles for myeloid cell adhesion molecules (SELE, ICAM5 and CD209) and the coagulation factor F8, all of which are potentially druggable targets. Our results are broadly consistent with a multi-component model of COVID-19 pathophysiology, in which at least two distinct mechanisms can predispose to life-threatening disease: failure to control viral replication; or an enhanced tendency towards pulmonary inflammation and intravascular coagulation. We show that comparison between cases of critical illness and population controls is highly efficient for the detection of therapeutically relevant mechanisms of disease

Potential of landrace winery by-products (<i>Vitis vinifera L.</i>) as a source of phenolic compounds with antioxidant properties

Aim: To evaluate the potential of the main winery by-products – pressed pomaces, fermented pomaces and stems –, derived from minor grape varieties (Escursac, Gorgollassa and Sabater as red varieties, Giró ros and Quigat as white varieties) native to the Balearic Islands (Spain), as raw material for the production of phenolic concentrates with antioxidant properties. Methods and results: Total phenolics, tannins and anthocyanins, as well as antioxidant capacity of winery by-products were spectrophotometrically evaluated and compared to those of Cabernet sauvignon and Chardonnay varieties. In general, stems presented higher average total phenolic (5.57 ± 1.25 g/100 g dm) and total tannin (10.26 ± 2.10 g/100 g dm) contents than the corresponding pomaces, with the landrace variety Escursac being that which exhibited the highest values (p < 0.05). For pomaces, those sampled after the fermentation process presented larger amounts of polyphenols than those collected just after the pressing process, and the fermented pomaces from the autochthonous varieties Escursac and Sabater were those with the highest potential. Conclusion: The present research demonstrated that landrace minor varieties denoted similar, or even higher, phenolic and antioxidant potential than the reference grape varieties. The characterization performed might be the basis for their integrated use and revalorization as promising sources of phenolic concentrates, despite not having still undergone the selection process that the traditional grape varieties have been subjected to as a result of decades of intensive production. Significance and impact of the study: To the best of our knowledge, this is the first time that the phenolic composition and antioxidant properties of winery by-products from grape varieties native to the Balearic Islands are examined. Due to the increasing use of these minor grape varieties in winemaking, the phenolic characterization of their by-products is of great interest for the wine sector, which could exploit these underutilized resources more efficiently and extensively so as to support sustainable agricultural production

Moisture profiles in cheese drying determined by TD-NMR: Mathematical modeling of mass transfer

[EN] A time-domain nuclear magnetic resonance (TD-NMR) method is proposed to quick and easily determine moisture profiles during cheese drying. The method consists of a combined relaxation analysis, where the magnetization at a certain time is determined by both the longitudinal and the transverse NMR relaxation processes. The drying experiments were carried out at 16 °C and 0.2-0.5 m/s for 32 days, and allowing only one-direction mass transfer. A diffusion model was formulated taking into account the external resistance to mass transfer. Both effective moisture diffusivity and external mass transfer coefficient were simultaneously identified (3.71 × 10 -11 m 2/s and 2.95 × 10 -8 m/s, respectively). The proposed model allowed a satisfactory simulation of both the drying curve (mean relative error (MRE) = 0.4% and percentage of explained variance (%var) = 99.7%) and the moisture profiles (average MRE = 4.4% and %var = 94.5%). © 2011 Elsevier Ltd. All rights reserved.The authors would like to acknowledge the financial support provided by the Government of Spain through the MEC (AP-2005-4847) and the MECI (AGL2006-14146-C02-02).Castell Palou, A.; Rossello, C.; Femenia, A.; Bon Corbín, J.; Simal, S. (2011). Moisture profiles in cheese drying determined by TD-NMR: Mathematical modeling of mass transfer. Journal of Food Engineering. 104(4):525-531. https://doi.org/10.1016/j.jfoodeng.2011.01.010S525531104

Influence of the Addition of Dietary Fiber on the Drying Curves and Microstructure of a Dry Fermented Sausage (Sobrasada)

[EN] The formulation of a dry fermented sausage has been modified by the addition of carrot dietary fiber (CDF; 3, 6, 9, and 12% [w/w]), and the influence of this change on the drying curves and food microstructure has been studied. The CDF content influenced the initial moisture content as well as the drying rate. A diffusion model taking into account the change in the product formulation has been proposed to simulate the drying curves. A constant mass transfer coefficient of 2.53 x 10(-8) m/s was obtained and the effective water diffusivity varied exponentially with the CDF content from 0.99 x 10(-11) m(2)/s (0% CDF) to 2.08 x 10(-11) m(2)/s (12% CDF). The simulation of the drying curves was satisfactory (mean relative error of 0.5 +/- 0.1%). No differences in the microstructure related to the proteolytic process were found among samples with different CDF contents.The authors acknowledge financial support from the MICINN (Ministerio de Ciencia Innovacion, Gobiernode Espana) (DPI2009-14549-C04-02) and the Conselleria d'Educacio, Cultura i Universitats (Govern de les Illes Balears).Eim, VS.; García Pérez, JV.; Roselló, C.; Femenia, A.; Simal, S. (2012). Influence of the Addition of Dietary Fiber on the Drying Curves and Microstructure of a Dry Fermented Sausage (Sobrasada). Drying Technology. 30(2):146-153. doi:10.1080/07373937.2011.628428S14615330

Compositional and structural features of the main bioactive polysaccharides present in the Aloe vera plant

[eng] Aloe vera (A. barbadensis Miller) is probably one of the most popular plants, widely studied because of numerous properties associated with the polysaccharides present in its gel. In particular, two main types of bioactive polysaccharides can be distinguished in the A. vera gel: an acetylated mannose-rich polymer that functions as storage polysaccharide, and a galacturonic acid-rich polymer as the main component comprising the cell walls of the parenchymatous tissue. Interestingly, most of the beneficial properties related to the aloe plant have been associated with the acetylated mannose-rich polysaccharide, also known as acemannan. However, the composition and structural features of these polysaccharides, as well as the beneficial properties associated with them, may be altered by different factors, such as the climate, soil, postharvest treatments, and processing. Further, different analytical methods have been used not only to identify but also to characterize the main polysaccharides found in parenchyma of A. vera leaf. Within this context, the main aim of this review is to summarize the most relevant information about the structural and compositional features of the main polysaccharides found in the A. vera gel as well as the most relevant analytical techniques used for their identification and their influence on the technological, functional, and beneficial properties related to the A. vera plant