Gold nanoparticles (AuNP) stimulate immune responses in mammals but they have not been tested in species of relevance in aquaculture. In this study the immunostimulant and protective potential of ...orally administered AuNP against V. parahaemolyticus, the causative agent of Acute Hepatopancreatic Necrosis Disease, was determined in shrimp. Synthetized AuNP (18.57 ± 4.37 nm) were moderately dispersed with a negative ζ potential of −10.3 ± 0.208 mV (pH = 7). AuNP were administered (single dose) at 0.2, 2, and 20 μg/g feed in shrimp. Hemolymph samples were withdrawn daily for 6 days. Hemolymph or hemocytes were used to determine total hemocyte counts, immune-related enzymatic activities, and expression of immune-relevant genes. Hepatopancreas was sampled for the analysis of AuNP biodistribution and histological examination. Survival was recorded daily. No mortality or toxicity signs in hepatopancreas were found. AuNP were detected in hepatopancreas. Early (24–48 h) immunostimulation was mainly related to immune gene up-regulation. Upon a challenge with V. parahaemolyticus, survival was higher (80%) and histopathological damages were lower in shrimp treated with the 2 μg/g dose when compared to the control. Therefore orally administered AuNP are proposed as immunostimulants that protect shrimp against V. parahaemolyticus infection.
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•AuNP synthetized and physicochemically characterized were orally administered in shrimp.•No toxicity signs were observed in shrimp received AuNP.•AuNP were detected in the shrimp's hepatopancreas.•Shrimp were early immunostimulated (24–48 h) upon AuNP single oral administration.•Higher survival and lower histopathology in shrimp fed AuNP and infected with V. parahaemolyticus.
Metformin consumption for diabetes treatment is increasing, leading to its presence in wastewater treatment plants where conventional methods cannot remove it. Therefore, this work aims to analyze ...the performance of advanced oxidation processes using sulfate radicals in the degradation of metformin from water. Experiments were performed in a photoreactor provided with a low-pressure Hg lamp, using K2S2O8 as oxidant and varying the initial metformin concentration (CA0), oxidant concentration (Cox), temperature (T), and pH in a response surface experimental design. The degradation percentages ranged from 26.1 to 87.3%, while the mineralization percentages varied between 15.1 and 64%. Analysis of variance (ANOVA) showed that the output variables were more significantly affected by CA0, Cox, and T. Besides, a reduction of CA0 and an increase of Cox up to 5000 μM maximizes the metformin degradation since the generation of radicals and their interaction with metformin molecules are favored. For the greatest degradation percentage, the first order apparent rate constant achieved was 0.084 min−1. Furthermore, while in acidic pH, temperature benefits metformin degradation, an opposite behavior is obtained in a basic medium because of recombination and inhibition reactions. Moreover, three degradation pathways were suggested based on the six products detected by HPLC-MS: N-cyanoguanidine m/z = 85; N,N-dimethylurea m/z = 89; N,N-dimethyl-cyanamide m/z = 71 N,N-dimethyl-formamide m/z = 74; glicolonitrilo m/z = 58; and guanidine m/z = 60. Finally, it was shown that in general the toxicity of the degradation byproducts was lower than the toxicity of metformin toward Chlamydomonas reinhardtii.
Starch branching enzymes (SBEs) play important roles in plant starch synthesis. Three orthologs encoding SBEs in rice,
Arabidopsis thaliana, and
Populus trichocarpa are described. Putative amino acid ...sequences of these three
SBE genes show ∼
30% identity to those of SBEI and SBEII from plants such as maize, barley, and wheat. More interestingly, they share ∼
31% amino acid sequence identity with those of glycogen-branching enzymes from such animals as mouse, horse, and monkey. The three genes have similar genomic structures, but their structural features are quite different from those of genes of both
SBEI and
SBEII families in plants. Based on phylogenetic analysis and genomic structure comparison, it is proposed that the three
SBE genes represent a new family of SBEs.
Vaccination is a crucial approach to eradicate
and control amyriad of infectious and non-communicable
diseases. Subunit vaccines are considered the most convenient
approach for vaccine formulation; ...however, the
development of new adjuvants and vaccine delivery vehicles
to improve the immunogenicity of such formulations
is needed. The authors of this review describe the recent
application of porous silicon particles (PSiP) as both a potential
vaccine delivery vehicle and adjuvant. PSiP are attractive
for this application due to its safety, biodegradability
and compatibility for functionalization. Herein, the
development of multi-epitope cancer vaccines is discussed
as an example on how PSiP are promising materials for the
development of innovative vaccines.
The use of food-grade organisms as recombinant vaccine expression hosts and delivery vehicles has been explored during the past 25 years, opening new avenues for vaccinology. Considering that oral ...immunization is a beneficial approach in terms of costs, patient comfort, and protection of mucosal tissues, the use of food-grade organisms can lead to highly advantageous vaccines in terms of costs, easy administration, and safety. The organisms currently used for this purpose are bacteria ( Lactobacillus and Bacillus) , yeasts, algae, plants, and insect species. Herein, a comparative and updated scenario on the production of oral vaccines in food-grade organisms is provided and placed in perspective. The status of clinical evaluations and the adoption of this technology by the industry are highlighted.
MINCLE is a C‐lectin receptor mainly expressed in macrophages to recognize carbohydrates enhanced by the innate immune response in mammals and fish. Toxin A (ToxA) from Vibrio parahaemolyticus N16 ...was evaluated as an antigenic protein; it was observed to induce IgM production, increase cytokine gene expression, and offer immunoprotection against bacterial challenges in fish. This study was aimed at analysing the MINCLE receptor from the Pacific red snapper (Lutjanus peru) through bioinformatics tools, and the stimulating effects of β‐glucans from Sterygmatomyces halophilus 4 N16 (β‐Glu/Sh) combined with an antigenic protein on head–kidney leukocytes (HKLs) before and on challenge with Vibrio parahaemolyticus N16. LpMincle was mainly expressed in the intestine, eyes and head–kidney tissues. Before and after V. parahaemolyticus challenge, an up‐regulation of the receptors (Mincle, Marco and tlr2) and pro‐inflammatory cytokines (il‐1β and il‐6) gene expression was observed in HKLs incubated with β‐Glu/Sh. Respiratory burst activity was mainly enhanced in cells incubated with ToxA before and after V. parahaemolyticus infection. Nitric oxide (NO) production increased in leukocytes incubated with β‐Glu/Sh or ToxA, whereas myeloperoxidase (MPO) activity augmented only after ToxA stimulation before the bacterial challenge. In conclusion, MINCLE from L. peru was characterized in silico and its effects on HKLs was identified. Receptors and pro‐inflammatory cytokine genes up‐regulated by β‐Glu/Sh alone or in combination with ToxA can be elicitors of innate immune parameters. These findings evidence the function and recognition of novel β‐glucans from yeast either alone or in combination with antigenic proteins by β‐glucan receptors and their cytokines response.
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