Association of Cytogenetics Aberrations and IGHV Mutations with Outcome in Chronic Lymphocytic Leukemia Patients in a Real-World Clinical Setting.

Immunoglobulin heavy chain variable ( IGHV ) region mutations, TP53 mutation, fluorescence in situ hybridization (FISH), and cytogenetic analysis are the most important prognostic biomarkers used in chronic lymphocytic leukemia (CLL) patients in our daily practice. In real-life environment, there are scarce studies that analyze the correlation of these factors with outcome, mainly referred to time to first treatment (TTFT) and overall survival (OS). This study aimed to typify IGHV mutation status, family usage, FISH aberrations, and complex karyotype (CK) and to analyze the prognostic impact in TTFT and OS in retrospective study of 375 CLL patients from a Spanish cohort. We found unmutated CLL (U-CLL) was associated with more aggressive disease, shorter TTFT (48 vs. 133 months, p < 0.0001), and shorter OS (112 vs. 246 months, p < 0.0001) than the mutated CLL. IGHV3 was the most frequently used IGHV family (46%), followed by IGHV1 (30%) and IGHV4 (16%). IGHV5-51 and IGHV1-69 subfamilies were associated with poor prognosis, while IGHV4 and IGHV2 showed the best outcomes. The prevalence of CK was 15% and was significantly associated with U-CLL. In the multivariable analysis, IGHV2 gene usage and del13q were associated with longer TTFT, while VH1-02, +12, del11q, del17p, and U-CLL with shorter TTFT. Moreover, VH1-69 usage, del11q, del17p, and U-CLL were significantly associated with shorter OS. A comprehensive analysis of genetic prognostic factors provides a more precise information on the outcome of CLL patients. In addition to FISH cytogenetic aberrations, IGHV and TP53 mutations, IGHV gene families, and CK information could help clinicians in the decision-making process.

The branched mitochondrial respiratory chain from the jellyfish Stomolophus sp2 as a probable adaptive response to environmental changes.

During their long evolutionary history, jellyfish have faced changes in multiple environmental factors, to which they may selectively fix adaptations, allowing some species to survive and inhabit diverse environments. Previous findings have confirmed the jellyfish's ability to synthesize large ATP amounts, mainly produced by mitochondria, in response to environmental challenges. This study characterized the respiratory chain from the mitochondria of the jellyfish Stomolophus sp2 (previously misidentified as Stomolophus meleagris). The in-gel activity from isolated jellyfish mitochondria confirmed that the mitochondrial respiratory chain contains the four canonical complexes I to IV and F0F1-ATP synthase. Specific additional activity bands, immunodetection, and mass spectrometry identification confirmed the occurrence of four alternative enzymes integrated into a branched mitochondrial respiratory chain of Stomolophus sp2: an alternative oxidase and three dehydrogenases (two NADH type II enzymes and a mitochondrial glycerol-3-phosphate dehydrogenase). The analysis of each transcript sequence, their phylogenetic relationships, and each protein's predicted models confirmed the mitochondrial alternative enzymes' identity and specific characteristics. Although no statistical differences were found among the mean values of transcript abundance of each enzyme in the transcriptomes of jellyfish exposed to three different temperatures, it was confirmed that each gene was expressed at all tested conditions. These first-time reported enzymes in cnidarians suggest the adaptative ability of jellyfish's mitochondria to display rapid metabolic responses, as previously described, to maintain energetic homeostasis and face temperature variations due to climate change.

Comparison of five commercial kits for isolation of total RNA in samples of WSSV-infected shrimp.

Viral diseases are the most serious threat to the expansion and development of shrimp aquaculture. Rapid diagnosis of the white spot syndrome virus (WSSV), a lethal shrimp pathogen, is essential to restrict its spread and reduce the mortality of infected shrimp. This virus has globally affected the shrimp farming industry, with a devastating economic impact. Several studies have focused on the expression of WSSV transcripts to understand the molecular mechanisms governing the pathological development of the disease. Since gene expression studies and molecular diagnostics at the early stages of infection depend on the efficient isolation of high-quality RNA, the extraction methods should be carefully selected. However, previous comparisons of the performance of RNA isolation kits have yet to be systematically investigated. In this study, 5 commercial RNA extraction methods were compared in WSSV-infected shrimp. The highest total RNA yield (ng mg-1 tissue) was obtained using TRIzol. Even though the 260/280 nm absorption ratios showed significant differences, the methods showed good purity values (>2.0). RNA integrity was evaluated in a denaturing agarose gel electrophoresis, and degradation was observed after the total RNA samples were treated with DNase I. Finally, the method that allowed the earlier detection of WSSV transcripts by qRT-PCR was the Zymo Direct-zol RNA MiniPrep kit. This study shows that the amount of observed (or estimated) WSSV transcripts might be affected because of the RNA isolation method. In addition, these results may contribute to improve the accuracy of the results obtained in gene expression studies, for more sensitive and robust detection of WSSV.

Development and validation of a real-time PCR assay protocol for the specific detection and quantification of pelagiphages in seawater samples.

Earth is inhabited by numerous adaptations of cellular forms shaped by the persistent scrutiny of natural selection. Thus, as natural selection has fixed beneficial adaptations of functional traits, cellular life has conquered almost all environmental niches on our planet. However, cellular life succumbs in number and genetic diversity to viruses. Among all viruses, phages are highly prevalent in diverse environments, and due to their vast genetic diversity and abundance, their relevant role as significant players in several ecological processes is now fully recognized. Pelagiphages, bacteriophages infecting bacteria of the SAR11 clade, are the most abundant viruses in the oceans. However, the ecological contribution of pelagiphages on populations of Pelagibacterales remains largely underestimated. An essential aspect of estimating the impact of bacteriophages is their absolute and precise quantification, which provides relevant information about the host-virus interactions and the structure of viral assemblages. Consequently, due to its abundance and claimed influence in the biogeochemical cycling of elements, the accurate quantification of pelagiphages results in an essential task. This study describes the development and validation of a sensitive, specific, accurate and reproducible qPCR platform targeting pelagiphages. Moreover, this method allowed the detection and quantification of pelagiphages in the Gulf of California for the first time.

Cellular and humoral immune responses and breakthrough infections after three SARS-CoV-2 mRNA vaccine doses.

Background: SARS-CoV-2 vaccination has proven the most effective measure to control the COVID-19 pandemic. Booster doses are being administered with limited knowledge on their need and effect on immunity. Objective: To determine the duration of specific T cells, antibodies and neutralization after 2-dose vaccination, to assess the effect of a third dose on adaptive immunity and to explore correlates of protection against breakthrough infection. Methods: 12-month longitudinal assessment of SARS-CoV-2-specific T cells, IgG and neutralizing antibodies triggered by 2 BNT162b2 doses followed by a third mRNA-1273 dose in a cohort of 77 healthcare workers: 17 with SARS-CoV-2 infection prior to vaccination (recovered) and 60 naïve. Results: Peak levels of cellular and humoral response were achieved 2 weeks after the second dose. Antibodies declined thereafter while T cells reached a plateau 3 months after vaccination. The decline in neutralization was specially marked in naïve individuals and it was this group who benefited most from the third dose, which resulted in a 20.9-fold increase in neutralization. Overall, recovered individuals maintained higher levels of T cells, antibodies and neutralization 1 to 6 months post-vaccination than naïve. Seventeen asymptomatic or mild SARS-CoV-2 breakthrough infections were reported during follow-up, only in naïve individuals. This viral exposure boosted adaptive immunity. High peak levels of T cells and neutralizing antibodies 15 days post-vaccination associated with protection from breakthrough infections. Conclusion: Booster vaccination in naïve individuals and the inclusion of viral antigens other than spike in future vaccine formulations could be useful strategies to prevent SARS-CoV-2 breakthrough infections.

Effect of functional diets on intestinal microbiota and resistance to Vibrio parahaemolyticus causing acute hepatopancreatic necrosis disease (AHPND) of Pacific white shrimp (Penaeus vannamei).

AIMS: The present study evaluated the effect of four functional diets and a reference diet on the survival and intestinal bacterial community of shrimp Penaeus vannamei infected with acute hepatopancreatic necrosis disease (AHPND). METHODS AND RESULTS: After 42 days of feeding trail, shrimp were inoculated with a Vibrio parahaemolyticus (CIB-0018-3) carrying the plasmid encoding for the PirAB toxins responsible for AHPND. After 120 h postinfection (hpi), shrimp fed with a diet containing 2% of a mix with Curcuma longa and Lepidium meyenii (TuMa) and a diet containing 0.2% of vitamin C (VitC) showed a significantly higher survival (85%) compared to the remaining treatments (50%-55%) (p < 0.05). Infected shrimp fed with TuMa diet, showed a significant reduction of Vibrionales, and VitC diet promoted an increase of Alteromonadales. CONCLUSIONS: Our findings suggest that the TuMa diet conferred protection against AHPND and could be attributed to a combined effect of antibacterial properties against Vibrionales, and promoting a desirable bacterial community in the shrimp intestine, while the VitC diet protection could be attributed to their antioxidant capacity and in a lower proportion to a bacterial modulation in shrimp gut. SIGNIFICANCE AND IMPACT OF THE STUDY: Acute hepatopancreatic necrosis disease is a devastating disease that significantly affects aquaculture production of shrimps. Therefore, the use of functional diets that promote resistance to AHPND represents a valuable tool to reduce the mortality of farmed shrimp.

Effect of pH and Carbon Source on Phosphate Solubilization by Bacterial Strains in Pikovskaya Medium.

Phosphate-solubilizing bacteria (PSB) transform precipitated inorganic phosphorus into soluble orthophosphates. This study evaluated the efficiency of tricalcium and iron phosphate solubilization in Pikovskaya medium using five bacterial strains (A1, A2, A3, A5, and A6) cultured in acidic and alkaline pH levels. The bacterial strain that proved to be more efficient for P solubilization and was tolerant to pH variations was selected for assessing bacterial growth and P solubilization with glucose and sucrose in the culture medium. The bacterial strains were identified through 16S rRNA gene sequencing as Pseudomonas libanensis A1, Pseudomonas libanensis (A2), Bacillus pumilus (A3), Pseudomonas libanensis (A5), and Bacillus siamensis (A6). These five bacterial strains grew, tolerated pH changes, and solubilized inorganic phosphorus. The bacterial strain A3 solubilized FePO4 (4 mg L-1) and Ca3(PO4)2 (50 mg L-1). P solubilization was assayed with glucose and sucrose as carbon sources for A3 (Bacillus pumilus MN100586). After four culture days, Ca3(PO4)2 was solubilized, reaching 246 mg L-1 with sucrose in culture media. Using glucose as a carbon source, FePO4 was solubilized and reached 282 mg L-1 in six culture days. Our findings were: Pseudomonas libanensis, and Bacillus siamensis, as new bacteria, can be reported as P solubilizers with tolerance to acidic or alkaline pH levels. The bacterial strain B. pumilus grew using two sources of inorganic phosphorus and carbon, and it tolerated pH changes. For that reason, it is an ideal candidate for inorganic phosphorus solubilization and future production as a biofertilizer.

Differential expression of heat shock protein genes in Rhipicephalus sanguineus (Acari: Ixodidae) exposed to temperature and humidity variations.

The brown dog tick (Rhipicephalus sanguineus), a well-recognized parasite that is an important vector of many pathogens, widely distributed in the world, can be found in dogs and many other host animals, including humans. However, the response of this species to climate changes is not fully understood yet. Therefore, this study aimed to analyze the expression of the genes encoding for hsp20 and hsp70 of nymphs and eggs of R. sanguineus in response to different relative humidity and temperature. While no significant differences were observed in hsp70 levels in nymphs, striking variations were found for hsp20. On the contrary, significant differences were found on the expression levels of both HSPs when exposed at different treatments. Expression of hsp20 was more affected by relative humidity than by temperature, which could imply that hsp20 may have a more critical protective role during vulnerable developmental stages of the tick than hsp70.

Adaptive mitochondrial response of the whiteleg shrimp Litopenaeus vannamei to environmental challenges and pathogens.

In most eukaryotic organisms, mitochondrial uncoupling mechanisms control ATP synthesis and reactive oxygen species production. One such mechanism is the permeability transition of the mitochondrial inner membrane. In mammals, ischemia-reperfusion events or viral diseases may induce ionic disturbances, such as calcium overload; this cation enters the mitochondria, thereby triggering the permeability transition. This phenomenon increases inner membrane permeability, affects transmembrane potential, promotes mitochondrial swelling, and induces apoptosis. Previous studies have found that the mitochondria of some crustaceans do not exhibit a calcium-regulated permeability transition. However, in the whiteleg shrimp Litopenaeus vannamei, contradictory evidence has prevented this phenomenon from being confirmed or rejected. Both the ability of L. vannamei mitochondria to take up large quantities of calcium through a putative mitochondrial calcium uniporter with conserved characteristics and permeability transition were investigated in this study by determining mitochondrial responses to cations overload. By measuring mitochondrial swelling and transmembrane potential, we investigated whether shrimp exposure to hypoxia-reoxygenation events or viral diseases may induce mitochondrial permeability transition. The results of this study demonstrate that shrimp mitochondria take up large quantities of calcium through a canonical mitochondrial calcium uniporter. Neither calcium nor other ions were observed to promote permeability transition. This phenomenon does not depend on the life cycle stage of shrimp, and it is not induced during hypoxia/reoxygenation events or in the presence of viral diseases. The absence of the permeability transition phenomenon and its adaptive meaning are discussed as a loss with biological advantages, possibly enabling organisms to survive under harsh environmental conditions.

Obtención e infusión de plasma convaleciente de paciente recuperado de infección COVID-19 para uso compasivo / Obtaining and infusing convalescent plasma from a patient recovered from COVID-19 infection for compassionate use

El 30 de enero de 2020, la Organización Mundial de la Salud (OMS) declara que el brote de Enfermedad por Coronavirus (COVID-19) constituye una Emergencia Sanitaria de Salud de Preocupación Internacional/Public Health Emergencies of International Concern (PHEIC). El 11 de marzo de 2020, la OMS declara la pandemia1,2. El COVID-19 es una enfermedad respiratoria aguda causada por un coronavirus zoonótico de reciente aparición1. Los coronavirus son una familia de virus que se descubrió en la década de los 60 pero cuyo origen es todavía desconocido. Pueden causar enfermedades tanto en animales como en humanos. En los humanos se sabe que varios coronavirus (229E, OC43, NL63 y HUK 1) son responsables del resfriado común y en raras ocasiones se pueden producir infecciones graves de las vías respiratorias inferiores. Dos de los coronavirus causan infecciones en los seres humanos muchos más graves e incluso a veces mortales; estos son: el Coronavirus del Síndrome Respiratorio de Oriente Medio (MERS-CoV), y el Coronavirus tipo 2 asociado al SARS (SARS-CoV), que produce el síndrome respiratorio agudo grave3,4. La pandemia debida al virus SARS-CoV-2 requiere de medidas sanitarias urgentes encaminadas a reducir el riesgo de transmisión de la infección3,4. Al momento, no existe tratamiento eficaz para abordar la enfermedad por SARS-CoV-2 (COVID-19). La OMS emitió un informe que los primeros resultados con el uso de Plasma de Convaleciente (CP) puede ser una modalidad de tratamiento potencialmente útil para el COVID-193-5.En este sentido, se señaló la oportunidad de que los Sistemas Transfusionales de cada país realicen una evaluación de riesgos para calibrar su capacidad de extraer, preparar y almacenar este tipo de donaciones. Esto incluye recursos humanos y suministros críticos adecuados, así como un control exhaustivo de procedimientos e infraestructuras. En este marco, se sugiere el inicio de contactos con los servicios hospitalarios para que colaboren en la selección de pacientes, que habiendo superado la enfermedad del COVID-19, pudieran ser candidatos para donación de plasma sin mermar en sus derechos1. La decisión de desarrollar esta opción requiere una revisión rápida, pero exhaustiva, del agente etiológico o agentes relacionados y la respuesta inmune a ellos para evaluar los posibles beneficios y riesgos de la inmunización pasiva. Los principios generales establecidos en los documentos de posición de la Red de Reguladores de Sangre (BRN) de la OMS sobre el uso de plasma convaleciente, como elemento de respuesta a brotes anteriores de virus emergentes (2017) y como respuesta al Coronavirus del Síndrome Respiratorio de Oriente Medio (2014) siguen siendo aplicables también a esta pandemia de SARS-CoV-26,7. La falta de evidencia clínica concluyente del uso del plasma convaleciente en infección por SARS-CoV-2 no debería ser razón para abandonar el uso del plasma convaleciente. Los ensayos clínicos aleatorios están en curso y los resultados no estarán disponibles durante meses en tanto no hay justificación basada en la evidencia disponible y la ética profesional para negar categóricamente el uso del plasma convaleciente en los hospitales que no participan en un ensayo clínico aleatorio. El siguiente protocolo ha tomado algunas de las recomendaciones del Comité Científico para la Seguridad Transfusional del Ministerio de Sanidad de España Versión 1.0 ­ 26 marzo de 20201. Y ha sido modificado para tratar de adaptarlo a la realidad de nuestra institución.

On January 30, 2020, the World Health Organization (WHO) declared that the COVID-19 outbreak constitutes a public health emergency of international concern (PHEIC). On March 11, 2020, the WHO declared the pandemic1,2. COVID-19 is an acute respiratory disease caused by a newly emerging zoonotic coronavirus1. Coronaviruses are a family of viruses that was discovered in the 1960s but whose origin is still unknown. They can cause disease in both animals and humans. In humans, several coronaviruses (229E, OC43, NL63, and HUK 1) are known to be responsible for the common cold, and serious infections of the lower respiratory tract can rarely occur. Two of the coronaviruses cause much more serious and even sometimes fatal infections in humans; These are: MERS-CoV, as the cause of respiratory syndrome in the Middle East, and SARS-CoV, which produces severe acute respiratory syndrome3,4. The pandemic due to the SARS-CoV-2 virus requires urgent sanitary measures aimed at reducing the risk of transmission of the infection3,4. Currently, there is no effective treatment to address SARS-CoV-2 disease (COVID-19). The WHO issued a report that early results with the use of convalescent plasma (PC) may be a potentially useful treatment modality for COVID-193-5. In this sense, the opportunity for the Transfusion Systems of each country to carry out a risk assessment to gauge their ability to extract, prepare and store this type of donation. This includes adequate critical human resources and supplies, as well as a comprehensive control of procedures and infrastructure. In this framework, it is suggested that contacts with hospital services be initiated so that they collaborate in the selection of patients who, having overcome the COVID-19 disease, may be candidates for plasma donation without diminishing their rights1. The decision to develop this option requires a rapid, but comprehensive, review of the etiologic agent or related agents and the immune response to them to assess the possible benefits and risks of passive immunization. The general principles established in the position papers of the WHO Blood Regulators Network (BRN) on the use of convalescent plasma, as an element of response to previous outbreaks of emerging viruses (2017) and as a response to the syndrome coronavirus respiratory problems of the Middle East (2014) are still applicable to this SARS-CoV-2 pandemic6,7. The lack of conclusive clinical evidence of the use of convalescent plasma in SARS-CoV-2 infection should not be a reason to abandon the use of convalescent plasma. Randomized clinical trials are ongoing and results will not be available for months as there is no justification based on available evidence and professional ethics to categorically deny the use of convalescent plasma in hospitals that do not participate in a randomized clinical trial. The following protocol has taken some of the recommendations of the Scientific Committee for Transfusion Safety of the Spanish Ministry of Health Version 1.0 - March 26, 20201. And it has been modified to try to adapt it to the reality of our institution.

Respuesta a diferentes escenarios y complicaciones hematológicas en COVID-19 / Response to different scenarios and hematological complications in COVID-19.

Las enfermedades infecciosas emergentes y reemergentes son desafíos constantes para la salud pública en todo el mundo. Los casos recientes de neumonía de causa desconocida en Wuhan, China, han llevado al descubrimiento de un nuevo tipo de Coronavirus (2019-nCoV), que son virus de Ácido Ribonucleico (RNA) envueltos, de forma común encontrados en humanos, otros mamíferos y aves, capaces de causar enfermedades respiratorias, entéricas, hepáticas y neurológicas 1. La amenaza a la salud de la infección por Coronavirus 2 asociado al SRAS (SARS-CoV-2) y la enfermedad que produce el mismo llamada Enfermedad por Coronavirus (COVID-19) ya está estable- cida con sus tasas de infección y mortalidad de manera considerable más altas si se lo compara con otros virus respiratorios adquiridos en la comunidad 2. En tal sentido es necesario dar una respuesta por parte de la Unidad Técnica de Hematología en relación a esta pandemia con el ánimo de aportar al manejo integral de estos pacientes, homogeneizar criterios clínicos, lidiar de mejor manera con la incertidumbre en el diagnóstico y tratamiento de COVID-19. El SARS CoV-2 y su enfermedad COVID-19, en la mayoría de pacientes tiene una presentación con síntomas leves. Sin embargo, en el 5% de los casos diagnosticados requerirán de una Unidad de Cuidados Intensivos (UCI)3, ya que presentan Síndrome de Dificultad Respiratoria Aguda (SDRA), shock séptico, Insuficiencia Multiorgánica y coagulopatía hemorrágica, así como trombótica, incluyendo Coagulación Intravascular Diseminada (CID), alcanzado en las salas de UCI una tasa mortalidad por COVID-19 entre el 22% al 62% en algunas series 4. Adicional, se ha observado que el grupo de pacientes con mala evolución presentan un estado hiperinflamatorio, asemejándose al cuadro clínico descrito de una linfohistiocitosis hemofagocítica secundaria, que en este caso sería desencadenada por SARS CoV-2 5. Un grupo de Hematólogos de diferentes hospitales de la ciudad de Quito: Especialidades Carlos Andrade Marín-Instituto Ecuatoriano de Seguridad Social (HECAM-IESS), Metropolitano; y, hospitales de la ciudad de Guayaquil: Teodoro Maldonado Carbo-IESS, Hospital Luis Vernaza y Clínica Gilbert, basados en la evidencia científica disponible y experticia profesional, elaboraron éste protocolo con las recomendaciones según los diferentes escenarios y complicaciones hematológicas.

Emerging and reemerging infectious diseases are constant challenges to public health worldwide. Recent cases of pneumonia of unknown cause in Wuhan, China have led to the discovery of a new type of Coronavirus (2019-nCoV), which are enveloped ribonucleic acid (RNA) viruses, commonly found in humans, other mammals, and birds, capable of cause respiratory, enteric, liver and neurological diseases 1. The health threat of SARS-associated coronavirus 2 (SARS-CoV-2) and the disease that produces it called COVID-19 has already been established with its considerably higher infection and mortality rates compared to other respiratory viruses acquired in the community 2. In this sense, it is necessary to give a response from the Hematology Technical Unit in relation to this pandemic in order to contribute to the comprehensive management of these patients, homogenize clinical criteria, better deal with uncertainty in the diagnosis and treatment of COVID-19. SARS CoV-2 and its disease COVID-19, in the majority of patients have a presentation with mild symptoms. However, in 5% of diagnosed cases they will require an Intensive Care Unit (ICU) 3, since they present Acute Respiratory Distress Syndrome (ARDS), septic shock, Multiple Organ Failure and hemorrhagic coagulopathy, as well as thrombotic, including Coagulation Disseminated Intravascular (DIC), achieved in the ICU wards a mortality rate for COVID-19 between 22% and 62% in some series 4. Additionally, it has been observed that the group of patients with poor evolution present a hyperinflammatory state, resembling the clinical picture of secondary hemopha- gocytic lymphohistiocytosis, which in this case would be triggered by SARS CoV-2 5. The group of Hematologists from the hospitals of the city of Quito: Specialties Carlos Andrade Marín HECAM-IESS, Metropolitano; and, hospitals in the city of Guayaquil: Teodoro Maldonado Carbo-IESS, Luis Vernaza Hospital and Gilbert Clinic, based on the available scientific evidence and professional expertise, prepared this protocol with the recommendations according to the different hematological scenarios and complications.

White spot syndrome virus down-regulates expression of histones H2A and H4 of Penaeus vannamei to promote viral replication.

The white spot syndrome virus (WSSV) is a highly lethal and contagious pathogen to most cultivated shrimp species. The WSSV genome contains the ICP11 gene and its encoded protein acts as a multifunctinal DNA mimic protein that disrupts the nucleosome assembly by binding to the histone proteins H2A and H3. In addition, WSSV provokes severe nuclear hypertrophy and DNA damage. However, little is known about the influence of WSSV on the expression of the host's genes encoding for histones. Therefore, we investigated the effect of WSSV infection on the expression of the genes encoding histones in shrimp Penaeus vannamei. An RT-qPCR assay was performed to evaluate the temporal expression of H2A and H4 transcripts in the shrimp. Significant changes were observed in the expression of these genes, which coincided with the dynamics of replication of the virus. H2A reached its maximum expression levels at 12 hpi. Thus, it may be suggested that this is a viral strategy to evade the host's immune response in order to promote viral replication.

The white spot syndrome virus hijacks the expression of the Penaeus vannamei Toll signaling pathway to evade host immunity and facilitate its replication.

The white spot syndrome virus (WSSV), the most lethal pathogen of shrimp, is a dsDNA virus with approximately a 300,000 base pairs and contains approximately 180-500 predicted open reading frames (ORFs), of which only 6% show homology to any known protein from other viruses or organisms. Although most of its ORFs encode enzymes for nucleotide metabolism, DNA replication, and protein modification, the WSSV uses some of its encoded proteins successfully to take control of the metabolism of the host and avoid immune responses. The contribution of the shrimp innate immune response to prevent viral invasions is recognized but yet not fully understood. Thus, the role of several components of Toll pathway of the shrimp Penaeus vannamei against WSSV has been previously described, and the consequential effects occurring through the cascade remain unknown. In the current study the effects of WSSV over various components of the shrimp Toll pathway were studied. The gene expression of Spätzle, Toll, Tube, Cactus and Dorsal was altered after 6-12 h post inoculation. The expression of LvToll3, LvCactus, LvDorsal, decreased ~4.4-, ~3.7- and ~7.3-fold at 48, 24 and 48 hpi, respectively. Furthermore, a remarkable reduction (~18-fold) in the expression of the gene encoding LvCactus in WSSV infected specimens was observed at 6 hpi. This may be a sophisticated strategy exploited by WSSV to evade the Toll-mediated immune action, and to promote its replication, thereby contributing to viral fitness.

Analysis of lipid peroxidation in animal and plant tissues as field-based biomarker in Mediterranean irrigated agroecosystems (Extremadura, Spain).

The development of field-based biomarkers can allow for a more reliable assessment of the exposure of organisms to pollutants. Different sampling sites, along two streams running through an irrigable agricultural area, were selected to evaluate the effect of agrochemical load on the measured endpoints. The levels of lipid peroxidation were evaluated in several organs of Procambarus clarkii. The same method was applied to leaves of two woody species. Determining levels of MDA (malonaldehyde) by thiobarbituric acid reactive substances assay allows measuring the levels of lipid peroxidation. Differences in lipid peroxidation levels were observed in P. clarkii individuals collected at different sites; however, the patterns varied depending on the organ (when accounting for variations due to sex). The use of a MDA-gills/MDA-hepatopancreas index allowed for discrimination between reference and polluted sites. Significant differences in oxidative damage between sites were found in the leaves of Quercus rotundifolia but not in Salix sp. The lipid peroxidation of crayfish organs and holm oak leaves as a suitable biomarker of environmental pollution deserves further investigation.

A novel thymidylate synthase from the Vibrionales, Alteromonadales, Aeromonadales, and Pasteurellales (VAAP) clade with altered nucleotide and folate binding sites.

Thymidylate synthase (TS, E.C. 2.1.1.45) is a crucial enzyme for de novo deoxythymidine monophosphate (dTMP) biosynthesis. The gene for this enzyme is thyA, which encodes the folate-dependent TS that converts deoxyuridine monophosphate group (dUMP) into (dTMP) using the cofactor 5,10-methylenetetrahydrofolate (mTHF) as a carbon donor. We identified the thyA gene in the genome of the Vibrio parahaemolyticus strain FIM-S1708+ that is innocuous to humans but pathogenic to crustaceans. Surprisingly, we found changes in the residues that bind the substrate dUMP and mTHF, previously postulated as invariant among all TSs known (Finer-Moore, Santi & Stroud, 2003). Interestingly, those amino acid changes were also found in a clade of microorganisms that contains Vibrionales, Alteromonadales, Aeromonadales, and Pasteurellales (VAAP) from the Gammaproteobacteria class. In this work, we studied the biochemical properties of recombinant TS from V. parahemolyticus FIM-S1708+ (VpTS) to address the natural changes in the TS amino acid sequence of the VAAP clade. Interestingly, the Km for dUMP was 27.3 ± 4.3 µM, about one-fold larger compared to other TSs. The Km for mTHF was 96.3 ± 18 µM, about three- to five-fold larger compared to other species, suggesting also loss of affinity. Thus, the catalytic efficiency was between one or two orders of magnitude smaller for both substrates. We used trimethoprim, a common antibiotic that targets both TS and DHFR for inhibition studies. The IC50 values obtained were high compared to other results in the literature. Nonetheless, this molecule could be a lead for the design antibiotics towards pathogens from the VAAP clade. Overall, the experimental results also suggest that in the VAAP clade the nucleotide salvage pathway is important and should be investigated, since the de novo dTMP synthesis appears to be compromised by a less efficient thymidylate synthase.

De novo assembly and transcriptome characterization of the freshwater prawn Palaemonetes argentinus: Implications for a detoxification response.

Palaemonetes argentinus, an abundant freshwater prawn species in the northern and central region of Argentina, has been used as a bioindicator of environmental pollutants as it displays a very high sensitivity to pollutants exposure. Despite their extraordinary ecological relevance, a lack of genomic information has hindered a more thorough understanding of the molecular mechanisms potentially involved in detoxification processes of this species. Thus, transcriptomic profiling studies represent a promising approach to overcome the limitations imposed by the lack of extensive genomic resources for P. argentinus, and may improve the understanding of its physiological and molecular response triggered by pollutants. This work represents the first comprehensive transcriptome-based characterization of the non-model species P. argentinus to generate functional genomic annotations and provides valuable resources for future genetic studies. Trinity de novo assembly consisted of 24,738 transcripts with high representation of detoxification (phase I and II), anti-oxidation, osmoregulation pathways and DNA replication and bioenergetics. This crustacean transcriptome provides valuable molecular information about detoxification and biochemical processes that could be applied as biomarkers in further ecotoxicology studies.

Deadly acute Decompression Sickness in Risso's dolphins.

Diving air-breathing vertebrates have long been considered protected against decompression sickness (DCS) through anatomical, physiological, and behavioural adaptations. However, an acute systemic gas and fat embolic syndrome similar to DCS in human divers was described in beaked whales that stranded in temporal and spatial association with military exercises involving high-powered sonar. More recently, DCS has been diagnosed in bycaught sea turtles. Both cases were linked to human activities. Two Risso's dolphin (Grampus griseus) out of 493 necropsied cetaceans stranded in the Canary Islands in a 16-year period (2000-2015), had a severe acute decompression sickness supported by pathological findings and gas analysis. Deadly systemic, inflammatory, infectious, or neoplastic diseases, ship collision, military sonar, fisheries interaction or other type of lethal inducing associated trauma were ruled out. Struggling with a squid during hunting is discussed as the most likely cause of DCS.

The Pacific oyster (Crassostrea gigas) Hsp70 modulates the Ostreid herpes virus 1 infectivity.

The Ostreid herpes virus type 1 (OsHV-1) is one of the most devastating pathogen in oyster cultures. Among several factors, as food limitation, oxygen depletion, salinity and temperature variations, episodes of "summer mortality" of the Pacific oyster Crassostrea gigas have also been associated with OsHV-1 infection. Mortalities of C. gigas spat and juveniles have increased significantly in Europe, and contemporary mortality records of this mollusk in México have been associated with the occurrence of OsHV-1. In the present study, the expression of the heat shock protein 70 gene from the Pacific oyster correlates with the abundance of DNA polymerase transcripts from the OsHV-1. This may suggest that the induction on the expression of the Pacific oyster hsp70 may potentially participate in the immune response against the virus. Furthermore, this study reports for the first time a TEM representative image of the OsHV-1 in aqueous solution, which possesses an icosahedral shape with a diameter of 70 nm × 100 nm. Finally, the examined sequence encoding the ORF4 of the OsHV-1 isolate from northwest Mexico showed specific sequence variations when compared with OsHV-1 isolates from distant geographical areas.

Proteasome properties of hemocytes differ between the whiteleg shrimp Penaeus vannamei and the brown shrimp Crangon crangon (Crustacea, Decapoda).

Crustaceans are intensively farmed in aquaculture facilities where they are vulnerable to parasites, bacteria, or viruses, often severely compromising the rearing success. The ubiquitin-proteasome system (UPS) is crucial for the maintenance of cellular integrity. Analogous to higher vertebrates, the UPS of crustaceans may also play an important role in stress resistance and pathogen defense. We studied the general properties of the proteasome system in the hemocytes of the whiteleg shrimp, Penaeus vannamei, and the European brown shrimp Crangon crangon. The 20S proteasome was the predominant proteasome population in the hemocytes of both species. The specific activities of the trypsin-like (Try-like), chymotrypsin-like (Chy-like), and caspase-like (Cas-like) enzymes of the shrimp proteasome differed between species. P. vannamei exhibited a higher ratio of Try-like to Chy-like activities and Cas-like to Chy-like activities than C. crangon. Notably, the Chy-like activity of P. vannamei showed substrate or product inhibition at concentrations of more than 25 mmol L-1. The K M values ranged from 0.072 mmol L-1 for the Try-like activity of P. vannamei to 0.309 mmol L-1 for the Cas-like activity of C. crangon. Inhibition of the proteasome of P. vannamei by proteasome inhibitors was stronger than in C. crangon. The pH profiles were similar in both species. The Try-like, Chy-like, and Cas-like sites showed the highest activities between pH 7.5 and 8.5. The proteasomes of both species were sensitive against repeated freezing and thawing losing ~80-90% of activity. This study forms the basis for future investigations on the shrimp response against infectious diseases, and the role of the UPS therein.

Selection and validation of candidate reference genes for quantitative real-time PCR studies in the shrimp Penaeus vannamei under viral infection.

The decapod Penstyldensovirus 1 (PstDV-1) represents one of the most serious threats for penaeid shrimp farming. Studies aimed at defining relevant molecular effects of this virus over its host are imperative in the attempt to increase our understanding of its pathogenesis. Unfortunately, few studies have focused on the definition of the expression profile of reference genes in shrimp challenged with a pathogen. As a result, there are no studies on the selection of reference genes for the normalization of target gene expression changes yielding reliable data of the effects following PstDV-1 infection in shrimp. Therefore, the aim of the present study was to evaluate and validate the appropriateness of four candidate reference genes (ef1-α, gapdh, rpl8 and ß-tubulin) for their use as reference genes to normalize qPCR data in gene expression studies of PstDV-1-shrimp interactions. By analyzing the expression profile of those genes, gapdh was validated as a suitable reference gene to normalize expression data gathered from a PstDV1-challenge, while ef1-α, ß-tubulin, and rpl8 were identified as unstably expressed during the infectious process. The suitability of gapdh as a common reference gene in studies of host gene response to viral infections is underlined.