Differential Composition and Structure of the Microbiota from Active and Inactive Stages of HLA-B27-associated Uveitis by Paired Fecal Metagenomes.

PURPOSE: To compare the diversities and abundances of bacterial taxa in the microbiome of patients with HLA B27-positive acute anterior uveitis (AAU) in the active and inactive phases. METHODS: An observational descriptive prospective and comparative study was conducted in ten HLA-B27-positive AAU patients (44.6 ± 13.4 years). The microbiome of the stool samples obtained in the active and inactive stages was analyzed by sequencing the V3 region of the 16S rRNA gene. RESULTS: The differences in the bacteria profile between active and inactive stages in each individual were confirmed (p < 0.0001). Ten OTUs were found exclusively in the active phase of 90% of the individuals, suggesting a proinflammatory association. Blautia OUT_4 and Faecalibacterium OUT_2 abundances showed a direct relationship between abundance and severity of ocular inflammation. Two OTUs were exclusive of the inactive stage, suggesting an anti-inflammatory role. CONCLUSION: The metagenomic profile of the fecal microbiota differs in the acute phase of the AAU compared to when the inflammation subsides, despite being the same individual and a short time-lapse. AAU is a fertile field for studying the connection between subtle rapid changes in microbiota and their systemic consequences.

Marine Toxins as Pharmaceutical Treasure Troves: A Focus on Saxitoxin Derivatives from a Computational Point of View.

This work highlights the significant potential of marine toxins, particularly saxitoxin (STX) and its derivatives, in the exploration of novel pharmaceuticals. These toxins, produced by aquatic microorganisms and collected by bivalve mollusks and other filter-feeding organisms, offer a vast reservoir of chemical and biological diversity. They interact with sodium channels in physiological processes, affecting various functions in organisms. Exposure to these toxins can lead to symptoms ranging from tingling sensations to respiratory failure and cardiovascular shock, with STX being one of the most potent. The structural diversity of STX derivatives, categorized into carbamate, N-sulfocarbamoyl, decarbamoyl, and deoxydecarbamoyl toxins, offers potential for drug development. The research described in this work aimed to computationally characterize 18 STX derivatives, exploring their reactivity properties within marine sponges using conceptual density functional theory (CDFT) techniques. Additionally, their pharmacokinetic properties, bioavailability, and drug-likeness scores were assessed. The outcomes of this research were the chemical reactivity parameters calculated via CDFT as well as the estimated pharmacokinetic and ADME properties derived using computational tools. While they may not align directly, the integration of these distinct datasets enriches our comprehensive understanding of the compound's properties and potential applications. Thus, this study holds promise for uncovering new pharmaceutical candidates from the considered marine toxins.

Exploring marine toxins: comparative analysis of chemical reactivity properties and potential for drug discovery.

Marine toxins, produced by various marine microorganisms, pose significant risks to both marine ecosystems and human health. Understanding their diverse structures and properties is crucial for effective mitigation and exploration of their potential as therapeutic agents. This study presents a comparative analysis of two hydrophilic and two lipophilic marine toxins, examining their reactivity properties and bioavailability scores. By investigating similarities among these structurally diverse toxins, valuable insights into their potential as precursors for novel drug development can be gained. The exploration of lipophilic and hydrophilic properties in drug design is essential due to their distinct implications on drug distribution, elimination, and target interaction. By elucidating shared molecular properties among toxins, this research aims to identify patterns and trends that may guide future drug discovery efforts and contribute to the field of molecular toxinology. The findings from this study have the potential to expand knowledge on toxins, facilitate a deeper understanding of their bioactivities, and unlock new therapeutic possibilities to address unmet biomedical needs. The results showcased similarities among the studied systems, while also highlighting the exceptional attributes of Domoic Acid (DA) in terms of its interaction capabilities and stability.

Computational Discovery of Marine Molecules of the Cyclopeptide Family with Therapeutic Potential.

Stellatolides are natural compounds that have shown promising biological activities, including antitumor, antimicrobial, and anti-inflammatory properties, making them potential candidates for drug development. Chemical Reactivity Theory (CRT) is a branch of chemistry that explains and predicts the behavior of chemical reactions based on the electronic structure of molecules. Conceptual Density Functional Theory (CDFT) and Computational Peptidology (CP) are computational approaches used to study the behavior of atoms, molecules, and peptides. In this study, we present the results of our investigation of the chemical reactivity and ADMET properties of Stellatolides A-H using a novel computational approach called Conceptual DFT-based Computational Peptidology (CDFT-CP). Our study uses CDFT and CP to predict the reactivity and stability of molecules and to understand the behavior of peptides at the molecular level. We also predict the ADMET properties of the Stellatolides A-H to provide insight into their effectiveness, potential side effects, and optimal dosage and route of administration, as well as their biological targets. This study sheds light on the potential of Stellatolides A-H as promising candidates for drug development and highlights the potential of CDFT-CP for the study of other natural compounds and peptides.

Talarolide A and Talaropeptides A-D: Potential Marine-Derived Therapeutic Peptides with Interesting Chemistry and Biological Activity Studied through Density Functional Theory (DFT) and Conceptual DFT.

Molecules sourced from marine environments hold immense promise for the development of novel therapeutic drugs, owing to their distinctive chemical compositions and valuable medicinal attributes. Notably, Talarolide A and Talaropeptides A-D have gained recent attention as potential candidates for pharmaceutical applications. This study aims to explore the chemical reactivity of Talarolide A and Talaropeptides A-D through the application of molecular modeling and computational chemistry techniques, specifically employing Conceptual Density Functional Theory (CDFT). By investigating their chemical behaviors, the study seeks to contribute to the understanding of the potential pharmacological uses of these marine-derived compounds. The molecular geometry optimizations and frequency calculations were conducted using the Density Functional Tight Binding (DFTBA) method. This was followed by a subsequent round of geometry optimization, frequency analysis, and computation of electronic properties and chemical reactivity descriptors. We employed the MN12SX/Def2TZVP/H2O model chemistry, utilizing the Gaussian 16 program and the SMD solvation model. The analysis of the global reactivity descriptors arising from CDFT was achieved as well as the graphical comparison of the dual descriptor DD revealing the areas of the molecules with more propensity to suffer a nucleophilic or electrophilic attack. Additionally, Molinspiration and SwissTargetPrediction were considered for the calculation of molecular characteristics and predicted biological targets. These include enzymes, nuclear receptors, kinase inhibitors, GPCR ligands, and ion channel modulators. The graphical results show that Talarolide A and the Talaropeptides A-D are likely to behave as protease inhibitors.

Quasi-Diamond Platelet-Shaped Zinc Oxide Nanostructures Display Enhanced Antibacterial Activity.

The current study compares the antibacterial activity of zinc oxide nanostructures (neZnO). For this purpose, two bacterial strains, Escherichia coli (ATCC 4157) and Staphylococcus aureus (ATCC 29213) were challenged in room light conditions with the aforementioned materials. Colloidal and hydrothermal methods were used to obtain the quasi-round and quasi-diamond platelet-shape nanostructures. Thus, the oxygen vacancy (VO ) effects on the surface of neZnO are also considered to assess its effects on antibacterial activity. The neZnO characterization was achieved by X-ray diffraction (XRD), a selected area electron diffraction (SAED) and Raman spectroscopy. The microstructural effects were monitored by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Furthermore, optical absorption ultraviolet visible spectrophotometry (UV-Vis) and X-ray photoelectron spectroscopy (XPS) analyses complement the physical characterization of these nanostructures; neZnO caused 50 % inhibition (IC50 ) at concentrations from 0.064 to 0.072 mg/mL for S. aureus and from 0.083 to 0.104 mg/mL for E. coli, indicating an increase in activity against S. aureus compared to E. coli. Consequently, quasi-diamond platelet-shaped nanostructures (average particle size of 377.6±10 nm) showed enhanced antibacterial activity compared to quasi-round agglomerated particles (average size of 442.8±12 nm), regardless of Vo presence or absence.

Levofloxacin induces differential effects in the transcriptome between the gut, peripheral and axial joints in the Spondyloarthritis DBA/1 mice: Improvement of intestinal dysbiosis and the overall inflammatory process.

To analyze the effect of levofloxacin-induced intestinal microbiota modifications on intestinal, joint, and systemic inflammation in the DBA/1 mice with spontaneous arthritis. The study included two groups of mice, one of which received levofloxacin. The composition and structure of the microbiota were determined in the mice's stool using 16S rRNA sequencing; the differential taxa and metabolic pathway between mice treated with levofloxacin and control mice were also defied. The effect of levofloxacin was evaluated in the intestines, hind paws, and spines of mice through DNA microarray transcriptome and histopathological analyses; systemic inflammation was measured by flow cytometry. Levofloxacin decreased the pro-inflammatory bacteria, including Prevotellaceae, Odoribacter, and Blautia, and increased the anti-inflammatory Muribaculaceae in mice's stool. Histological analysis confirmed the intestinal inflammation in control mice, while in levofloxacin-treated mice, inflammation was reduced; in the hind paws and spines, levofloxacin also decreased the inflammation. Microarray showed the downregulation of genes and signaling pathways relevant in spondyloarthritis, including several cytokines and chemokines. Levofloxacin-treated mice showed differential transcriptomic profiles between peripheral and axial joints and intestines. Levofloxacin decreased the expression of TNF-α, IL-23a, and JAK3 in the three tissues, but IL-17 behaved differently in the intestine and the joints. Serum TNF-α was also reduced in levofloxacin-treated mice. Our results suggest that the microbiota modification aimed at reducing pro-inflammatory and increasing anti-inflammatory bacteria could potentially be a coadjuvant in treating inflammatory arthropathies.

Genomic analysis finds no evidence of canonical eukaryotic DNA processing complexes in a free-living protist.

Cells replicate and segregate their DNA with precision. Previous studies showed that these regulated cell-cycle processes were present in the last eukaryotic common ancestor and that their core molecular parts are conserved across eukaryotes. However, some metamonad parasites have secondarily lost components of the DNA processing and segregation apparatuses. To clarify the evolutionary history of these systems in these unusual eukaryotes, we generated a genome assembly for the free-living metamonad Carpediemonas membranifera and carried out a comparative genomics analysis. Here, we show that parasitic and free-living metamonads harbor an incomplete set of proteins for processing and segregating DNA. Unexpectedly, Carpediemonas species are further streamlined, lacking the origin recognition complex, Cdc6 and most structural kinetochore subunits. Carpediemonas species are thus the first known eukaryotes that appear to lack this suite of conserved complexes, suggesting that they likely rely on yet-to-be-discovered or alternative mechanisms to carry out these fundamental processes.

Assessment of bacteriophage vB_Pd_PDCC-1 on bacterial dynamics during ontogenetic development of the longfin yellowtail (Seriola rivoliana).

The Seriola genus includes species of worldwide commercial importance due to its rapid growth and easy adaptability to confinement conditions. However, like other fish species, large mortalities occur during their early life stages, where the main problems are caused by opportunistic bacteria. Disease control strategies are thus urgently needed. The present study aimed to evaluate the efficacy of phage vB_Pd_PDCC-1 during the early development of longfin yellowtail (Seriola rivoliana), as well as its effect on microbial communities. This broad-host-range phage was added to the culture every 3 days starting from the egg-stage until 12 days after hatching (DAH) at a concentration of 1.41×1010 plaque-forming units (PFU) per mL and at a multiplicity of infection (MOI) of 1. The results showed positive effects (p<0.05) on egg hatching, survival, growth, and pigmentation area in treated larvae. Moreover, high-throughput sequencing analysis of 16S rRNA genes showed that phage administration did not produce significant changes (p>0.05) in the composition and structure of the associated microbiota. However, sequences affiliated to the Gammaproteobacteria class were displaced by those belonging to the Alphaproteobacteria class over time regardless of the treatment received. At the family level, there was a decrease in Rhodobacteraceae, Pseudoalteromonadaceae, and Flavobacteriaceae in both groups over time. To our best knowledge, this study represents the first attempt to evaluate the effect of a phage as a biological control agent during ontogenetic development of longfin yellowtail larvae. KEY POINTS: • Phages can be used against proliferation of Vibrio in fish cultures. • Seriola includes several important commercial fish species due to its rapid growth. • Phages do not cause significant changes in the associated microbiota.

Structure and predictive metabolic contribution of intestinal microbiota of Longfin yellowtail (Seriola rivoliana) juveniles in aquaculture systems.

Seriola rivoliana intestinal microbiota (IM) was characterised under aquaculture conditions through 16S rRNA amplicon sequencing. Specimens of 30 days after hatching (DAH) were maintained in three tanks and fed under the same environmental conditions for characterisation 15 days prior to sampling. Three fish were randomly taken from each tank; total DNA extraction of the gut microbiota was performed to characterise microbial composition and its metabolic prediction. The V3 hypervariable region of the 16S rRNA was amplified and sequenced with Illumina pair-end technology. The prokaryotic components in the S. rivoliana intestine were dominated mainly by the phyla Proteobacteria, Firmicutes, Bacteroidetes, Cyanobacteria and Actinobacteria. No significant differences in beta diversity were detected in the three samples (tanks). However in alpha diversity, they were detected in juveniles of the same cohort within the same group, as exemplified by enrichment of certain bacterial groups, mainly of the Clostridia class, which were specific in each fish within the same tank. The metabolic prediction analyses suggested that S. rivoliana IM contribute to the metabolism of amino acids, carbohydrates, lipids, and immune system. This study provides the first IM characterisation under rearing conditions of S. rivoliana-a species with broad economic potential-and contributes to novel information for potential use of probiotics in future trials.

Evaluation of Homeopathic Phosphoric Acid, Silica and Pathogenic Vibrio on Digestive Enzyme Activity of Longfin Yellowtail Fish (Seriola rivoliana).

BACKGROUND: This research aimed to observe the effect of homeopathically prepared Vibrio parahaemolyticus (ViP) and V. alginolyticus (ViA) and the commercial homeopathic compound Similia (Phosphoricum acidum and Silicea terra) on the digestive enzyme activities of Seriola rivoliana juveniles under usual culture conditions. MATERIALS AND METHODS: Biochemical analysis was used to study the effect of highly diluted substances (7C potency) prepared from ViP and ViA (Treatment 1: T1) and the homeopathic compound Phosphoricum acidum and Silicea terra (Treatment 2: T2) on changes in the main digestive enzymes on weaning-state fish (WS; 30 days post-hatching [DPH]) and early juveniles (EJ; 62 DPH) versus a reference control group that received no homeopathic medicines. RESULTS: Treatment T2 significantly increased the activity of trypsin and lipase and decreased the activity of amylase, whereas treatment T1 increased the activity of chymotrypsin and reduced the activity of aminopeptidase-N in WS fish. Except for alkaline phosphatase, which was significantly reduced in the intestine, no significant differences in enzymatic activity were found between treated EJ fish and controls. The fish of the WS group had a higher growth rate with the T2 treatment. CONCLUSIONS: T1 treatment stimulated chymotrypsin in EJ fish and T2 promoted intestinal maturation of WS fish. Higher growth rate with the T2 treatment may be associated with the stimulation of trypsin activity. Thus, T2 may be applied, under hatchery conditions, during larval stages with an aim to enhance digestion and assimilation of inert food.

Effect of Streptomyces probiotics on the gut microbiota of Litopenaeus vannamei challenged with Vibrio parahaemolyticus.

This study assessed the intestinal microbiota of juveniles of the White shrimp Litopenaus vannamei, whose feed was enriched with three probiotic formulations: Streptomyces sp. RL8 (RL8); a mix of Lactobacillus graminis and Streptomyces spp. RL8 and N7 (Lac-Strep); and a mix of Bacillus spp. and Streptomyces spp. RL8 and N7 (Bac-Strep). The analysis was performed by sequencing the V3 region of the 16S rRNA gene of treated animals and the control group before and after Vibrio parahaemolyticus challenge. After challenge, the highest Shannon diversity indexes corresponded to RL8 and Bac-Strep (3.94 ± 0.11 and 3.39 ± 0.3, respectively) and the lowest to the control group (2.58 ± 0.26). The most abundant phyla before and after challenge were Proteobacteria, Actinobacteria, and Bacteroidetes. The principal component analysis and Statistical Analysis of Metagenomic Profiles (STAMP) showed that the gut microbiota of the groups RL8 and Bac-Strep after challenge was different from the other experimental groups, which was characterized by a higher bacterial diversity, as well as a significant stimulation of the Bacteriovorax population and other antimicrobial producing genera that protected shrimp from infection.

Efecto de medicamentos homeopáticos sobre crecimiento, supervivencia y microbiota gastrointestinal, en juveniles del pectínido Argopecten ventricosus / Effect of homeopathic medicines on growth, survival and gastrointestinal microbiota of juvenile scallop Argopecten ventricosus

RESUMEN Objetivo. Estudiar el efecto de medicamentos homeopáticos sobre el crecimiento, supervivencia y microbiota del tracto gastrointestinal (TGI) de almeja Catarina Argopecten ventricosus. Materiales y Métodos. Se aplicaron cinco tratamientos homeopáticos derivados de bacterias [(T1) ViP-ViA 1D, (T2) ViP-ViA 7C], minerales [(T3) AcF-MsS 1D, (T4) PhA-SiT 7C], o venenos [(T5) ViT 31C] y tres controles: (C1) etanol diluido 1:99, (C2) etanol dinamizado 1C y (C3) agua destilada. La microbiota se determinó secuenciando la región V3-V5 del gen 16S rRNA. Resultados. El mayor crecimiento en longitud de la concha correspondió a T1 (117 µm d-1) y T2 (108 µm d-1), la mayor supervivencia a T3 y T5 y el mejor resultado global a T3. Las curvas de rarefacción de los grupos tratados y controles mostraron una clara separación. Se encontraron diferencias significativas (p≤0.05) entre filos (Proteobacteria > Actinobacteria > Firmicutes > Bacterloidetes> Chloroflexi y para los Géneros: Symbiobacterium > Microbacterium > Methylobacillus > Bacillus > Paenibacillus > Burkholderia > Nostoc > Methylobacterium > Leucobacter). El género Symbiobacterium fue dominante (p≤0.05) para T5, respecto a todos los tratamientos y grupos controles. La especie Microbacterium maritypicum (Actinobacteria) mostró la mayor abundancia relativa (p≤0.05) en T1 y T3 y Symbiobacterium toebii (Firmicutes) en T5 y T2 (p≤0.05), ambas con respecto al inicio del estudio T0. Conclusiones. Se presenta por primera vez la composición de la microbiota del TGI de A. ventricosus y la aplicabilidad potencial de la homeopatía para mejorar el rendimiento productivo y modular la microbiota gastrointestinal de la especie.

ABSTRACT Objective. To study the effect of homeopathic medicines on growth, survival and gastrointestinal (GIT) microbiota of Catarina scallop Argopecten ventricosus. Materials and methods. Five homeopathic (HOM) treatments derived from bacteria [(T1) ViP-ViA 1D, (T2) ViP-ViA 7C], minerals [(T3) AcF-MsS 1D, (T4) PhA-SiT 7C] or venoms [T5) ViT 31C] and three controls: [(C1) diluted ethanol 1:99, (C2) diluted/succussed ethanol 1C and (C3) distilled water] were evaluated (21 days) in triplicate. Microbiota was analysed by sequencing the V3-V5 region of the 16S rRNA genes. Results. The best growth in shell-length corresponded to T1 (117 µm d-1) and T2 (108 µm d-1) and the highest survival to T3 and T5, stating T3 as the best HOM-treatment. A clear separation was found in rarefaction curves of HOM-treated against un-treated control scallops. Significant differences (p≤0.05) were found for Phyla (Proteobacteria> Actinobacteria> Firmicutes> Bacterloidetes>Chloroflexi and for Genera: Symbiobacterium> Microbacterium> Methylobacillus> Bacillus> Paenibacillus> Burkholderia> Nostoc> Methylobacterium> Leucobacter). The genus Symbiobacterium was dominant in T5, finding significant differences (p≤0.05) with respect to all treatments. At species level, Microbacterium maritypicum (Actinobacteria) showed a greater relative abundance (p≤0.05) in T1 and T3 and Symbiobacterium toebii (Firmicutes) was also significantly higher (p≤0.05) in abundance in T5 and T2, both against initial T0. Conclusions. This study showed for a first time, the composition of GIT microbiota in A. ventricosus and focused on the potential applicability of homeopathy to improve overall performance and modulate the GIT microbiota of the species.

Immune and Antioxidant Enzyme Response of Longfin Yellowtail (Seriola rivoliana) Juveniles to Ultra-diluted Substances Derived from Phosphorus, Silica and Pathogenic Vibrio.

BACKGROUND: This research aimed to observe the effect of homeopathic treatments prepared from Vibrio parahaemolyticus and V. alginolyticus (H1) and commercial homeopathic medication Phosphoricum acidum and Silicea terra (H2) on the immune and antioxidant response in Seriola rivoliana juveniles under usual culture conditions and challenged with V. parahaemolyticus. MATERIALS AND METHODS: Quantitative polymerase chain reaction analysis was used to study changes in the expression of key genes related to immune response, cytokines (interleukin-1ß [IL-1ß]), adapter protein for cytokine release (MyD88) and piscidin and spectrophotometric techniques to analyze the activity of antioxidant superoxide dismutase (SOD) and catalase (CAT) enzymes in Seriola rivoliana juveniles at 30 (weaning stage [WS]) and 60 (early juveniles [EJ]) days post-hatching. RESULTS: The H1 treatment led to over-expression of the IL-1ß and MyD88 genes in fish at WS and EJ with respect to control, contrary to the H2 treatment that led to under-expression of the IL-1ß, MyD88 and piscidin genes at the EJ stage. In fish challenged with V. parahaemolyticus, both H1 and H2 led to over-expression of IL-1ß and MyD88; H2 caused an over-expression of piscidin. The SOD activity was higher in H1 with respect to H2 and the control group. CAT remained relatively stable with both H1 and H2 treatments. CONCLUSIONS: The results suggest that the overall effect of H1 was due to the presence of unknown antigens in low concentrations, while the response to H2-specifically during challenge-may have been due to a stimulating effect of nano-structures, prevailing from mother tincture after sequential dilution/succussion, in a pathway similar to that attributed to nano-vaccines.

Changes in digestive enzyme activities during early ontogeny of Seriola rivoliana.

This study contributes to basic knowledge on the development of larval digestive enzyme activities of Seriola rivoliana, a carnivorous species that has shown high mortality in larval stage. The study was conducted under laboratory-controlled conditions until larvae reached 30 days after hatching (DAH). The specific activity of amylase and pepsin was analysed by spectrophotometric methods, and lipase, trypsin, chymotrypsin and alkaline phosphatase by fluorometry. The results showed that S. rivoliana larvae had different enzyme patterns depending on their developmental stage, and also when exogenous food was administered (rotifers and Artemia). At hatching (2.98 ± 0.14 mm SL), lipase, alkaline phosphatase, trypsin and chymotrypsin activities were detected, but the last two enzymes showed an activity close to zero. Trypsin, chymotrypsin, lipase and alkaline phosphatase sharply increased their activities after starting the first feeding. Amylase activity was not detected until 5 DAH (3.51 ± 0.18 mm SL) and had a peak on day 15 (4.59 ± 0.39 mm SL); no activity was observed from then on. Pepsin activity was detected approximately at 15 DAH, showing a constant increase onwards. Trypsin had a peak on day 15 and then decreased on the following days. Chymotrypsin had the highest peak at 5 DAH, then a sharp decrease on day seven (3.88 ± 0.11 mm SL), and it increased gradually until day 30 (11.71 ± 1.59 mm SL). Lipase showed the highest activity at 15 DAH and then decreased its value. Finally, alkaline phosphatase showed the highest value at 3 DAH (3.62 ± 0.06 mm SL); then, a severe decrease was observed with activity stability on the following days. In conclusion, S. rivoliana larvae had a similar pattern as that observed in other marine-carnivorous fish larvae, so it could be considered as juvenile at 20 DAH in terms of digestive physiology; based on our results and previous study, the weaning process could start after this age, which would allow establishing a co-feeding protocol using inert diet.

Assessment of homeopathic medicines on survival and antioxidant response in white shrimp Litopenaeus vannamei / Evaluación de medicamentos homeopáticos en la supervivencia y respuesta antioxidante del camarón blanco Litopenaeus vannamei infectado con Vibrio parahaemolyticus

ABSTRACT Objective. Evaluating the effect of homeopathic medicines on survival and activity of the superoxide dismutase (SOD) enzyme in white shrimp Litopenaeus vannamei subjected to infection with the pathogenic Vibrio parahaemolyticus. Materials and methods . The average lethal dosage (LD50) was determined for the pathogen strain in L. vannamei juveniles under immersion (Imm), injection (Inj) and incision + immersion (Inc+Imm) methods. Four treatments were applied: (1) Mix CIB®-HOM Heel-Mix (TH1), constituted by equal v/v ratio, of Cyme-Heel®, Gal-Heel®, Hepa-Heel®, Mucs-Heel® and Chol-Heel®; (2) Mix CIB®-HOM Pav-Mix (TH2), constituted by the same v/v ratio of Passiflora incarnata, Valeriana officinalis, Zincum valerianicum and Ignatia amara (Similia®); (3) Heel-Mix/Pav-Mix (TH3) consisting of a 1:1 v/v combination of the TH1 and TH2 treatments, and (4) ViT-Mix (TH4), constituted by Vidatox®, and a control (not treated/infected). Results. While applying the methods Imm, Inj and Inc+Imm, LD50 was 0.9 x 106; 0.6 x 106 and 0.5 x 106 UFC.mL-1, respectively. At the end of the challenge, the groups treated with TH2, TH3 and TH4 had a greater survival rate to that of the control group (p<0.05). Moreover, these two last treatments showed a greater SOD activity with respect to the control group (p<0.05). Conclusions. The homeopathic treatments (TH3 and TH4) increased survival and SOD activity in L. vannamei juveniles challenged with V. parahaemolyticus, which suggests that the homeopathic treatments employed had the potential as an alternative for the control of V. parahaemolyticus and its associated diseases, including the early mortality syndrome in shrimp farming.

RESUMEN Objetivo. Evaluar el efecto de medicamentos homeopáticos sobre la supervivencia y actividad de la enzima superóxido dismutasa (SOD) del camarón Litopenaeus vannamei sometido a infección con Vibrio parahaemolyticus. Materiales y métodos. Se determinó la dosis letal media (DL50) para la cepa patógena en juveniles de L. vannamei, bajo los método de inmersión (Inm), inyección (Iny) e incisión + inmersión (Inc+Inm). Luego el efecto de cuatro medicamentos homeopáticos sobre juveniles de L. vannamei retados con Vibrio parahaemolyticus fue evaluado usando el índice la supervivencia y la actividad SOD. Se aplicaron cuatro tratamientos: (1) Mezcla CIB®-HOM Heel-Mix (TH1), constituido por igual proporción v/v, de Cyme-Heel®, Gal-Heel®, Hepa-Heel®, Mucs-Heel® y Chol-Heel®; (2) Mezcla CIB®-HOM Pav-Mix (TH2), constituido por igual proporción v/v de Passiflora incarnata, Valeriana officinalis, Zincum valerianicum e Ignatia amara (Similia®); (3) Heel-Mix/Pav-Mix (TH3) constituido por una combinación 1:1 v/v de los tratamientos TH1 y TH2, y (4) ViT-Mix (TH4), constituido por Vidatox®, y un control (no tratado/infectado). Resultados. Al aplicar los método Inm, Iny e Inc+Inm la DL50 fue de 0.9 x 106; 0.6 x 106 y 0.5 x 106 UFC.mL-1, respectivamente. Los camarones tratados con TH3 y TH4 presentaron una mayor actividad de SOD con respecto al grupo control (p<0.05). Al final del reto, los grupos TH2, TH3 y TH4 tuvieron una supervivencia mayor a la del grupo control (p<0.05). Conclusiones. Los tratamientos homeopáticos (TH3 y TH4), aumentaron la actividad de la enzima SOD y la supervivencia en juveniles de L. vannamei, retados con V. parahaemolyticus. Esto sugiere que los tratamientos homeopáticos empleados tienen potencial como alternativa para el control de V. parahaemolyticus y sus enfermedades asociadas, incluido el síndrome de mortalidad temprana en el cultivo del camarón.

Histological study of the gastrointestinal tract in longfin yellowtail (Seriola rivoliana) larvae.

This work contributes basic knowledge on larval development of Seriola rivoliana. A histological study describes the development of the digestive tract and accessory glands in S. rivoliana larvae reared under laboratory conditions at 24 °C from hatching to 30 days post-hatching (DPH). At hatching (2.6 ± 0.12 mm), larvae had an undifferentiated digestive tract with a closed straight tube and a large yolk sac with an oil globule. The liver and pancreas were observed at 1 and 2 days, and the mouth and anus opened at day 2. Enriched rotifers were visible in their digestive tract. At the beginning of the pre-flexion stage, a mixed nutritional period was observed. At day 3, exogenous feeding began; the digestive tract became differentiated into the buccopharynx, esophagus, an undifferentiated stomach, and the intestines. Zymogen granules were visible in the exocrine pancreas. At day 4, supranuclear vacuoles were present in the posterior intestine, indicating the beginning of intracellular digestion. At day 5, goblet cells were present in the esophagus and became functional at day 7 in the esophagus and intestine. The buccopharynx goblet cells developed at day 15. The presence of gastric glands and differentiation of the stomach in the fundic, cardiac, and pyloric regions during the post-flexion stage occurred at day 20. This was the onset of the juvenile period and the beginning of weaning; however, a long co-feeding phase is recommended. Pyloric caeca were observed at day 30 (13.6 ± 1.6 mm). These results provide valuable information on S. rivoliana larvae biology and digestive physiology, which should be useful to improve cultivation techniques and identify ecological features involved in ontogeny.