CRISPR/Cas-9 vector system: targets UL-39 and inhibits Simplexvirus humanalpha1 (HSV-1) replication in vitro.

Simplexvirus humanalpha1 (HSV-1) affects approximately 67% of the world's population. Here, we sought to use the CRISPR / Cas9 system with the UL39 target, essential for virus replication. The sgRNA sequence was inserted into the plasmid (PX459-UL39). Vero cells were transfected with PX459-UL39, and inhibition of viral replication was assessed 24 and 48 hours later using plaque assays and fluorescence and qPCR. Fluorescence analyses revealed the presence of anti-HSV-1 CRISPR/Cas9 within Vero cells, and qPCR showed that the viral load decreased by> 95% of cells transfected with anti-HSV-1 CRISPR / Cas 9. Our data demonstrate the usefulness of the PX459-UL39 to inhibit HSV-1 infection.

The plastome of Melocactus glaucescens Buining & Brederoo reveals unique evolutionary features and loss of essential tRNA genes.

MAIN CONCLUSION: The plastome of Melocactus glaucescens shows unique rearrangements, IR expansion, and unprecedented gene losses in Cactaceae. Our data indicate tRNA import from the cytosol to the plastids in this species. Cactaceae represents one of the richest families in keystone species of arid and semiarid biomes. This family shows various specific features comprehending morphology, anatomy, and metabolism, which allow them to grow under unfavorable environmental conditions. The subfamily Cactoideae contains the most divergence of species, which are highly variable in growth habit and morphology. This subfamily includes the endangered species Melocactus glaucescens (tribe Cereeae), which is a cactus endemic to the biome Caatinga in Brazil. Aiming to analyze the plastid evolution and develop molecular markers, we sequenced and analyzed in detail the plastome of M. glaucescens. Our analyses revealed that the M. glaucescens plastome is the most divergent among the species of the family Cactaceae sequenced so far. We characterized here unique rearrangements, expanded IRs containing an unusual set of genes, and several gene losses. Some genes related to the ndh complex were lost during the plastome evolution, while others have lost their functionality. Additionally, the loss of three tRNA genes (trnA-UGC, trnV-UAC, and trnV-GAC) suggests tRNA import from the cytosol to the plastids in M. glaucescens. Moreover, we identified high gene divergence, several putative positive signatures, and possible unique RNA-editing sites. Furthermore, we mapped 169 SSRs in the plastome of M. glaucescens, which are helpful to access the genetic diversity of natural populations and conservation strategies. Finally, our data provide new insights into the evolution of plastids in Cactaceae, which is an outstanding lineage adapted to extreme environmental conditions and a notorious example of the atypical evolution of plastomes.

A C. elegans model for neurodegeneration in Cockayne syndrome.

Cockayne syndrome (CS) is a congenital syndrome characterized by growth and mental retardation, and premature ageing. The complexity of CS and mammalian models warrants simpler metazoan models that display CS-like phenotypes that could be studied in the context of a live organism. Here, we provide a characterization of neuronal and mitochondrial aberrations caused by a mutation in the csb-1 gene in Caenorhabditis elegans. We report a progressive neurodegeneration in adult animals that is enhanced upon UV-induced DNA damage. The csb-1 mutants show dysfunctional hyperfused mitochondria that degrade upon DNA damage, resulting in diminished respiratory activity. Our data support the role of endogenous DNA damage as a driving factor of CS-related neuropathology and underline the role of mitochondrial dysfunction in the disease.

Cesarean Delivery and Risk of Excess Weight Among Brazilian Preschool Children.

OBJECTIVE: To study the relationship between cesarean Delivery (CD) and overweight in preschool children, considering the presence of birth aspects and demographic characteristics that have been associated with the risk of excess weight. METHODS: This retrospective cross-sectional analysis used representative data of children from 2 to 6 years of age at municipal daycare centers in Taubaté, São Paulo, Brazil. The sample included 752 preschoolers. Weight and height were collected in daycare centers, and the nutritional status classification was performed using z scores of Body Mass Index (zBMI). Data analysis was performed in the bivariate and multivariate manner, the latter with the inclusion of another possible risk factor. Adjustments were made for daycare centers time, sex, birth length and weight and maternal schooling. RESULTS: The mean age of preschool children was 4.7 years, and 53.8% were boys. The prevalence of overweight children was 21.7%. The median zBMI of the children born by CD was higher than that of vaginal Delivery (p = 0.0194). The prevalence of overweight showed association with CD (p = 0.0196; PR = 1.397 with 95% CI of 1065-1831). Logistic binary multivariate regression analysis confirmed the association, even in the presence of other possible risk factors (CR: 1.580, 95% CI: 1.072-2.330). CONCLUSION FOR PRACTICE: Birth by CD is one of the factors that are associated with the early development of overweight in preschoolers.

Callitrichine gammaherpesvirus 3 and Human alphaherpesvirus 1 in New World Primate negative for yellow fever virus in Rio de Janeiro, Brazil.

BACKGROUND: Herpesvirus transmission between humans and non-human primate (NHP) can occur through contact scratches with lesions, infected saliva, and mainly through contaminated food. Therefore, cross-infection can lead to severe illness or even death for both the animal and human. In 2017, during the yellow fever (YF) outbreak in Brazil, species of the New World Primates (NWP) from Rio de Janeiro state, tested negative for yellow fever virus (YFV) detection. OBJECTIVES: To evaluate herpesvirus in the population NWP in Rio de Janeiro. METHODS: To investigate, liver samples of 283 NWP, from several regions of the state of Rio de Janeiro, were tested for the herpesvirus family using a Pan-polymerase chain reaction (Pan-PCR) and sequencing. FINDINGS: 34.6% (98/283) tested positive for at least one herpesvirus; 29.3% (83/283) tested positive to Human alphaherpesvirus 1 (HSV-1), this virus from humans can be lethal to New World monkey; 13% (37/283) were detected Callitrichine gammaherpesvirus 3 (CalHV-3), responsible for lymphoproliferative disease that can be fatal in NWP. In addition, CalHV-3 / HSV-1 co-infection was in 11.6% (33/283) of the samples. MAIN CONCLUSIONS: Pan-herpesvirus was useful to identify species-specific herpesviruses and virus from human that can infect animals. Furthermore, during an outbreak of YF other infections should be monitored.

Human Gammaherpesvirus 8 Oncogenes Associated with Kaposi's Sarcoma.

Kaposi's sarcoma-associated herpesvirus (KSHV), also known as human gammaherpesvirus 8 (HHV-8), contains oncogenes and proteins that modulate various cellular functions, including proliferation, differentiation, survival, and apoptosis, and is integral to KSHV infection and oncogenicity. In this review, we describe the most important KSHV genes [ORF 73 (LANA), ORF 72 (vCyclin), ORF 71 or ORFK13 (vFLIP), ORF 74 (vGPCR), ORF 16 (vBcl-2), ORF K2 (vIL-6), ORF K9 (vIRF 1)/ORF K10.5, ORF K10.6 (vIRF 3), ORF K1 (K1), ORF K15 (K15), and ORF 36 (vPK)] that have the potential to induce malignant phenotypic characteristics of Kaposi's sarcoma. These oncogenes can be explored in prospective studies as future therapeutic targets of Kaposi's sarcoma.

Plastid genome evolution in Amazonian açaí palm (Euterpe oleracea Mart.) and Atlantic forest açaí palm (Euterpe edulis Mart.).

KEY MESSAGE: The plastomes of E. edulis and E. oleracea revealed several molecular markers useful for genetic studies in natural populations and indicate specific evolutionary features determined by vicariant speciation. Arecaceae is a large and diverse family occurring in tropical and subtropical ecosystems worldwide. E. oleracea is a hyperdominant species of the Amazon forest, while E. edulis is a keystone species of the Atlantic forest. It has reported that E. edulis arose from vicariant speciation after the emergence of the belt barrier of dry environment (Cerrado and Caatinga biomes) between Amazon and Atlantic forests, isolating the E. edulis in the Atlantic forest. We sequenced the complete plastomes of E. edulis and E. oleracea and compared them concerning plastome structure, SSRs, tandem repeats, SNPs, indels, hotspots of nucleotide polymorphism, codon Ka/Ks ratios and RNA editing sites aiming to investigate evolutionary traits possibly affected by distinct environments. Our analyses revealed 303 SNPs, 91 indels, and 82 polymorphic SSRs among both species. Curiously, the narrow correlation among localization of repetitive sequences and indels strongly suggests that replication slippage is involved in plastid DNA mutations in Euterpe. Moreover, most non-synonymous substitutions represent amino acid variants in E. edulis that evolved specifically or in a convergent manner across the palm phylogeny. Amino acid variants observed in several plastid proteins in E. edulis were also identified as positive signatures across palm phylogeny. The higher incidence of specific amino acid changes in plastid genes of E. edulis in comparison with E. oleracea probably configures adaptive genetic variations determined by vicariant speciation. Our data indicate that the environment generates a selective pressure on the plastome making it more adapted to specific conditions.

Maximal Diversity and Zipf's Law.

Zipf's law describes the empirical size distribution of the components of many systems in natural and social sciences and humanities. We show, by solving a statistical model, that Zipf's law co-occurs with the maximization of the diversity of the component sizes. The law ruling the increase of such diversity with the total dimension of the system is derived and its relation with Heaps's law is discussed. As an example, we show that our analytical results compare very well with linguistics and population datasets.

Bisphosphonate-related osteonecrosis induced change in alveolar bone architecture in rats with participation of Wnt signaling.

OBJECTIVE: This work aimed to study the role of inflammation in medication-related osteonecrosis of the jaw (MRONJ) in rats with focus on Wnt signaling. METHODS: A total of 36 female Wistar rats (12 weeks ± 200 g) were divided into 2 groups (n = 6) in 3 experiments: saline (SAL) and zoledronic acid (ZOL). For MRONJ induction, rats received 0.1 mg/kg of ZOL (ip) 3×/week for 9 weeks. Animals from the SAL group received 0.1 mg/kg of 0.9% SAL, ip 3×/week for 9 weeks. On the 8th week, 3 left upper molars were extracted, and on the 11th week, they were euthanized. Maxillae were evaluated by macroscopic and histopathological analyses; scanning electron microscopy (SEM); immunohistochemistry for DKK-1, Wnt 10b, and caspase-3; and Raman spectrometry. Gingiva was also collected for TNF-α e IL-1ß quantification. RESULTS: Bone necrosis was confirmed by healing impairment, reduced number of viable osteocytes, increased caspase-3 immunoexpression, and increased number of empty lacunae (p < 0.05). ZOL enhanced inflammation and increased gingival levels of IL-1ß and TNF-α (p < 0.05). Irregular indentations were seen on bone after ZOL administration. Bone necrosis was marked by reduced amount of total and type I collagen. ZOL reduced the mineral/matrix ratio and increased carbonate/phosphate ratio. It was observed a significant reduction on Wnt10b and beta-catenin immunolabeling in the bone tissue of ZOL group. CONCLUSION: In summary, MRONJ model caused bone necrosis due to intense inflammation. Wnt signaling seems to play an important role in this process. CLINICAL RELEVANCE: New therapeutic strategies focusing on Wnt pathway can provide an interesting approach for future treatments.

Phylogenetic and evolutionary features of the plastome of Tropaeolum pentaphyllum Lam. (Tropaeolaceae).

MAIN CONCLUSION: Complete plastome sequence of Tropaeolum pentaphyllum revealed molecular markers, hotspots of nucleotide polymorphism, RNA editing sites and phylogenetic aspects Tropaeolaceae Juss. ex DC. comprises approximately 95 species across North and South Americas. Tropaeolum pentaphyllum Lam. is an unconventional and endangered species with occurrence in some countries of South America. Although this species presents nutritional, medicinal and ornamental uses, genetic studies involving natural populations or promising genotypes are practically non-existent. Here, we report the nucleotide sequence of T. pentaphyllum plastome. It represents the first complete plastome sequence of the family Tropaeolaceae to be fully sequenced and analyzed in detail. The sequencing data revealed that the T. pentaphyllum plastome is highly similar to the plastomes of other Brassicales. Notwithstanding, our analyses detected some specific features concerning events of IR expansion and structural changes in some genes such as matK, rpoA, and rpoC2. We also detected 251 SSR loci, nine hotspots of nucleotide polymorphism, and two specific RNA editing sites in the plastome of T. pentaphyllum. Moreover, plastid phylogenomic inference indicated a closed relationship between the families Tropaeolaceae and Akaniaceae, which formed a sister group to Moringaceae-Caricaceae. Finally, our data bring new molecular markers and evolutionary features to be applied in the natural population, germplasm collection, and genotype selection aiming conservation, genetic diversity evaluation, and exploitation of this endangered species.

The plastomes of Astrocaryum aculeatum G. Mey. and A. murumuru Mart. show a flip-flop recombination between two short inverted repeats.

MAIN CONCLUSION: The plastomes of Astrocaryum murumuru and A. aculeatum revealed a lineage-specific structural feature originated by flip-flop recombination, non-synonymous substitutions in conserved genes and several molecular markers. Astrocaryum murumuru Mart. and A. aculeatum G.Mey. are two palm species of Amazon forest that are economically important as source of food, oil and raw material for several applications. Genetic studies aiming to establish strategies for conservation and domestication of both species are still in the beginning given that the exploitation is mostly by extractive activity. The identification and characterization of molecular markers are essential to assess the genetic diversity of natural populations of both species. Therefore, we sequenced and characterized in detail the plastome of both species. We compared both species and identified 32 polymorphic SSR loci, 150 SNPs, 46 indels and eight hotspots of nucleotide diversity. Additionally, we reported a specific RNA editing site found in the ccsA gene, which is exclusive to A. murumuru. Moreover, the structural analysis in the plastomes of both species revealed a 4.6-kb inversion encompassing a set of genes involved in chlororespiration and plastid translation. This 4.6-kb inversion is a lineage-specific structural feature of the genus Astrocaryum originated by flip-flop recombination between two short inverted repeats. Furthermore, our phylogenetic analysis using whole plastomes of 39 Arecaceae species placed the Astrocaryum species sister to Acrocomia within the tribe Cocoseae. Finally, our data indicated substantial changes in the plastome structure and sequence of both species of the genus Astrocaryum, bringing new molecular markers, several structural and evolving features, which can be applied in several areas such as genetic, evolution, breeding, phylogeny and conservation strategies for both species.

Genetic, evolutionary and phylogenetic aspects of the plastome of annatto (Bixa orellana L.), the Amazonian commercial species of natural dyes.

MAIN CONCLUSION: The plastome of B. orellana reveals specific evolutionary features, unique RNA editing sites, molecular markers and the position of Bixaceae within Malvales. Annatto (Bixa orellana L.) is a native species of tropical Americas with center of origin in Brazilian Amazonia. Its seeds accumulate the apocarotenoids, bixin and norbixin, which are only found in high content in this species. The seeds of B. orellana are commercially valued by the food industry because its dyes replace synthetic ones from the market due to potential carcinogenic risks. The increasing consumption of B. orellana seeds for dye extraction makes necessary the increase of productivity, which is possible accessing the genetic basis and searching for elite genotypes. The identification and characterization of molecular markers are essential to analyse the genetic diversity of natural populations and to establish suitable strategies for conservation, domestication, germplasm characterization and genetic breeding. Therefore, we sequenced and characterized in detail the plastome of B. orellana. The plastome of B. orellana is a circular DNA molecule of 159,708 bp with a typical quadripartite structure and 112 unique genes. Additionally, a total of 312 SSR loci were identified in the plastome of B. orellana. Moreover, we predicted in 23 genes a total of 57 RNA-editing sites of which 11 are unique for B. orellana. Furthermore, our plastid phylogenomic analyses, using the plastome sequences available in the plastid database belonging to species of order Malvales, indicate a closed relationship between Bixaceae and Malvaceae, which formed a sister group to Thymelaeaceae. Finally, our study provided useful data to be employed in several genetic and biotechnological approaches in B. orellana and related species of the family Bixaceae.

Cardiac hypertrophy in mice submitted to a swimming protocol: influence of training volume and intensity on myocardial renin-angiotensin system.

Exercise promotes physiological cardiac hypertrophy and activates the renin-angiotensin system (RAS), which plays an important role in cardiac physiology, both through the classical axis [angiotensin II type 1 receptor (AT1R) activated by angiotensin II (ANG II)] and the alternative axis [proto-oncogene Mas receptor (MASR) activated by angiotensin-(1-7)]. However, very intense exercise could have deleterious effects on the cardiovascular system. We aimed to analyze the cardiac hypertrophy phenotype and the classical and alternative RAS axes in the myocardium of mice submitted to swimming exercises of varying volume and intensity for the development of cardiac hypertrophy. Male Balb/c mice were divided into three groups, sedentary, swimming twice a day without overload (T2), and swimming three times a day with a 2% body weight overload (T3), totaling 6 wk of training. Both training groups developed similar cardiac hypertrophy, but only T3 mice improved their oxidative capacity. We observed that T2 had increased levels of MASR, which was followed by the activation of its main downstream protein AKT; meanwhile, AT1R and its main downstream protein ERK remained unchanged. Furthermore, no change was observed regarding the levels of angiotensin peptides, in either group. In addition, we observed no change in the ratio of expression of the myosin heavy chain ß-isoform to that of the α-isoform. Fibrosis was not observed in any of the groups. In conclusion, our results suggest that increasing exercise volume and intensity did not induce a pathological hypertrophy phenotype, but instead improved the oxidative capacity, and this process might have the participation of the RAS alternative axis.

The complete plastome of macaw palm [Acrocomia aculeata (Jacq.) Lodd. ex Mart.] and extensive molecular analyses of the evolution of plastid genes in Arecaceae.

MAIN CONCLUSION: The plastome of macaw palm was sequenced allowing analyses of evolution and molecular markers. Additionally, we demonstrated that more than half of plastid protein-coding genes in Arecaceae underwent positive selection. Macaw palm is a native species from tropical and subtropical Americas. It shows high production of oil per hectare reaching up to 70% of oil content in fruits and an interesting plasticity to grow in different ecosystems. Its domestication and breeding are still in the beginning, which makes the development of molecular markers essential to assess natural populations and germplasm collections. Therefore, we sequenced and characterized in detail the plastome of macaw palm. A total of 221 SSR loci were identified in the plastome of macaw palm. Additionally, eight polymorphism hotspots were characterized at level of subfamily and tribe. Moreover, several events of gain and loss of RNA editing sites were found within the subfamily Arecoideae. Aiming to uncover evolutionary events in Arecaceae, we also analyzed extensively the evolution of plastid genes. The analyses show that highly divergent genes seem to evolve in a species-specific manner, suggesting that gene degeneration events may be occurring within Arecaceae at the level of genus or species. Unexpectedly, we found that more than half of plastid protein-coding genes are under positive selection, including genes for photosynthesis, gene expression machinery and other essential plastid functions. Furthermore, we performed a phylogenomic analysis using whole plastomes of 40 taxa, representing all subfamilies of Arecaceae, which placed the macaw palm within the tribe Cocoseae. Finally, the data showed here are important for genetic studies in macaw palm and provide new insights into the evolution of plastid genes and environmental adaptation in Arecaceae.

Hepatitis B Virus-Hepatitis D Virus mother-to-child co-transmission: A retrospective study in a developed country.

BACKGROUND & AIMS: Hepatitis B Virus (HBV) DNA during chronic infection can reach levels at which mother-to-child (MTC) transmission frequently occurs despite passive-active immunization of newborns. Hepatitis D Virus (HDV) RNA can reach high levels, we assessed HBV/HDV MTC co-transmission. METHODS: Monocentric retrospective study (registered in ClinicalTrials.gov (NCT02044055)), after informed consent in HBV/HDV co-infected women pregnant between 01/01/2004 and 01/01/2015 in Paris, France. The children were tested when 24 months of age or older. RESULTS: Twenty-two (3%) of 742 HBV infected women, HDV co-infected, gave birth to 54 children during the study period. HBV DNA was above 5 Log10 I.U/mL in 10 pregnancies previous any treatment, with HDV RNA of less than 2.3 Log10 I.U/mL. HDV RNA was above 5 Log10 I.U/mL in eight pregnancies previous any treatment, with HBV DNA of less than 1.5 Log10 I.U/mL. Inverse patterns of HBV DNA and HDV RNA were observed in 17 of 35 (49%) pregnancies: 13 (76%) received no HBV treatment; four (24%) were treated. HBV DNA was under 5 Log10 I.U/mL in 46 of the 50 assessed women (92%) at birth. Of the 36 assessed children, given passive-active immunization, 24 (66%) were protected, 10 (28%) were neither infected nor protected, one was chronically HBV infected, and one had a past HBV infection. HDV Ab was negative in the 36 children. CONCLUSIONS: These results suggest that HBV/HDV MTC co-transmission is exceptional. Studies are needed, mainly in developing countries.

The Linum usitatissimum L. plastome reveals atypical structural evolution, new editing sites, and the phylogenetic position of Linaceae within Malpighiales.

KEY MESSAGE: The plastome of Linum usitatissimum was completely sequenced allowing analyses of evolution of genome structure, RNA editing sites, molecular markers, and indicating the position of Linaceae within Malpighiales. Flax (Linum usitatissimum L.) is an economically important crop used as food, feed, and industrial feedstock. It belongs to the Linaceae family, which is noted by high morphological and ecological diversity. Here, we reported the complete sequence of flax plastome, the first species within Linaceae family to have the plastome sequenced, assembled and characterized in detail. The plastome of flax is a circular DNA molecule of 156,721 bp with a typical quadripartite structure including two IRs of 31,990 bp separating the LSC of 81,767 bp and the SSC of 10,974 bp. It shows two expansion events from IRB to LSC and from IRB to SSC, and a contraction event in the IRA-LSC junction, which changed significantly the size and the gene content of LSC, SSC and IRs. We identified 109 unique genes and 2 pseudogenes (rpl23 and ndhF). The plastome lost the conserved introns of clpP gene and the complete sequence of rps16 gene. The clpP, ycf1, and ycf2 genes show high nucleotide and aminoacid divergence, but they still possibly retain the functionality. Moreover, we also identified 176 SSRs, 20 tandem repeats, and 39 dispersed repeats. We predicted in 18 genes a total of 53 RNA editing sites of which 32 were not found before in other species. The phylogenetic inference based on 63 plastid protein-coding genes of 38 taxa supports three major clades within Malpighiales order. One of these clades has flax (Linaceae) sister to Chrysobalanaceae family, differing from earlier studies that included Linaceae into the euphorbioid clade.

Effect of body weight and composition on efavirenz, atazanavir or darunavir concentration.

BACKGROUND: To compare the steady state plasma concentrations (Css) of three antiretroviral drugs in both normal and overweight patients, and to determine the relationship between Css and fat mass (FM) or lean body mass. METHODS: Patients treated for more than 6 months once daily with one of the antiretroviral drugs: efavirenz (EFV) 600mg, atazanavir boosted with ritonavir (ATV-r) 300mg/100mg, or darunavir boosted with ritonavir (DRV-r) 800mg/100mg, combined with two nucleoside analogues, were enrolled prospectively. One at steady state, plasma samples for the assessment of drug concentration were taken and body composition was assessed by bioelectrical impedance. RESULTS: One hundred and thirty-nine patients were enrolled (46, 45 and 48 in the groups EFV, ATV-r and DRV-r respectively). Their mean age was 46.2±10.4 years, 58% were male, 55.4% were from Sub Sahara African (SSA); body mass index (BMI) was 25.4±4.4kg/m2. Mean drug plasma Css of the three drugs did not differ according to BMI group. DRV-r Css tended to be higher in patients with BMI≥25kg/m2 (2896.7±1689 versus 2091.9±1038, P=0.09) and was significantly correlated with FM (r=0.3, P=0.02). In subgroup analysis, the effect of FM on DRV-r Css was significant in patients from SSA (r=0.4, P=0.04). CONCLUSIONS: Css result from many factors and body composition has been shown to only weakly influence interindividual variability but should be investigated in morbidly obese patients treated with DRV-r.

Application of multiplex real-time polymerase chain reaction assay for simultaneous quantification of Escherichia coli virulence genes in oysters.

Strains of diarrheagenic Escherichia coli (DEC) are involved in foodborne disease outbreaks worldwide, especially the enterohemorrhagic E. coli O157:H7. This study describes two multiplex quantitative real time PCR (qPCR) assays for simultaneous identification and quantification of genes related to virulence of DEC; a triplex reaction for detection and quantification of stxA1, stxA2, and eaeA genes, and a duplex reaction for detection and quantification of eaeA and virA genes. The technique was applied in raw oyster samples for direct quantification of DEC, thereby evaluating the applicability of this methodology for microbiological quality assessment of food. Using custom designed primers and specific MGB probes, a triplex qPCR assay was performed to quantify stxA1, stxA2, and eaeA, and a duplex reaction was performed to quantify virA and eaeA genes. The assays showed high sensitivity, with the detection limit varying between 5 and 17 copies of the genes. The coefficient of determination (R2) of the standard curves was 0.99. The coefficient of variation was < 1% indicated high intra- and inter-assay reproducibilities. The application of this methodology in oyster samples from tropical environment provided direct quantitative data that determined the presence of the genes stxA1 (32.1%), eaeA (28.6%), stxA2 (3.6%), and virA (3.6%). This would prove critical for immediate intervention of control strategies, particularly in oysters that are often ingested as raw food.

An integrative overview of the molecular and physiological responses of sugarcane under drought conditions.

Drought is the main abiotic stress constraining sugarcane production. However, our limited understanding of the molecular mechanisms involved in the drought stress responses of sugarcane impairs the development of new technologies to increase sugarcane drought tolerance. Here, an integrated approach was performed to reveal the molecular and physiological changes in two closely related sugarcane cultivars, including the most extensively planted cultivar in Brazil (cv. RB867515), in response to moderate (-0.5 MPa) and severe (-1 MPa) drought stress at the transcriptional, translational, and posttranslational levels. The results show common and cultivar exclusive changes in specific genes related to photosynthesis, carbohydrate, amino acid, and phytohormone metabolism. The novel phosphoproteomics and redox proteomic analysis revealed the importance of posttranslational regulation mechanisms during sugarcane drought stress. The shift to soluble sugar, secondary metabolite production, and activation of ROS eliminating processes in response to drought tolerance were mechanisms exclusive to cv. RB867515, helping to explain the better performance and higher production of this cultivar under these stress conditions.

Morphophysiological and biochemical alterations in Ricinus communis L. seeds submitted to cobalt60 gamma radiation.

This study aimed to evaluate the radiosensitivity of castor bean seeds after applications of different doses of Cobalt60 gamma radiation. Seeds were pre-soaked for 24 hours in distilled water and then irradiated with 50, 100, 150, and 200 Gy, except the control. Sowing was performed in trays, which contained soil as substrate and were maintained in a greenhouse. The electrical conductivity, emergence, emergence speed index, growth parameters and activities of antioxidant enzymes (superoxide dismutase, ascorbate peroxidase, and catalase) were evaluated in the leaves and roots of castor bean seedlings. Gamma radiation did not affect the electrical conductivity of the seeds; however, at a dose of 200 Gy, the emergence and emergence speed index of the seedlings was negatively affected. An analysis of the morphophysiological parameters revealed a reduction in seedling size as the radiation dose increased. There was a significant increase in superoxide dismutase and ascorbate peroxidase activities at higher radiation doses in the leaves, but not in roots. Thus, the analysis of all the variables suggests a response pattern as to the morphophysiological and biochemical changes of castor bean seedlings due to the increase of gamma radiation, which may serve as a tool for generating greater genetic variability.