Eugenol specialty chemical production in transgenic poplar (Populus tremula × P. alba) field trials

A foundational study assessed effects of biochemical pathway introduction into poplar to produce eugenol, chavicol, p‐anol, isoeugenol and their sequestered storage products, from potentially available substrates, coniferyl and p‐coumaryl alcohols. At the onset, it was unknown whether significant carbon flux to monolignols vs. other phenylpropanoid (acetate) pathway metabolites would be kinetically favoured. Various transgenic poplar lines generated eugenol and chavicol glucosides in ca. 0.45% (~0.35 and ~0.1%, respectively) of dry weight foliage tissue in field trials, as well as their corresponding aglycones in trace amounts. There were only traces of any of these metabolites in branch tissues, even after ~4‐year field trials. Levels of bioproduct accumulation in foliage plateaued, even at the lowest introduced gene expression levels, suggesting limited monolignol substrate availability. Nevertheless, this level still allows foliage collection for platform chemical production, with the remaining (stem) biomass available for wood, pulp/paper and bioenergy product purposes. Several transformed lines displayed unexpected precocious flowering after 4‐year field trial growth. This necessitated terminating (felling) these particular plants, as USDA APHIS prohibits the possibility of their interacting (cross‐pollination, etc.) with wild‐type (native plant) lines. In future, additional biotechnological approaches can be employed (e.g. gene editing) to produce sterile plant lines, to avoid such complications. While increased gene expression did not increase target bioproduct accumulation, the exciting possibility now exists of significantly increasing their amounts (e.g. 10‐ to 40‐fold plus) in foliage and stems via systematic deployment of numerous ‘omics’, systems biology, synthetic biology and metabolic flux modelling approaches.     

Personalized Medicine in Pediatrics: The Clinical Potential of Orodispersible Films

Children frequently receive medicines that are designed for adults. The dose of commercially available products is adapted, mostly based on the child’s bodyweight, thereby neglecting differences in pharmacokinetic and pharmacodynamics parameters. If commercial products are unsuitable for administration to children or are unavailable, extemporaneous pharmacy preparations are a good alternative. For this particular population, orodispersible films (ODFs) can be a highly attractive dosage form for the oral administration of drugs. ODFs are relatively easy to prepare in a hospital setting, create dose flexibility, and may suit an individual approach, especially for patients having difficulties in swallowing tablets or being fluid restricted. In this article, various aspects related to pharmacy preparations, clinical application, and preparation of ODFs for pediatric patients are highlighted and discussed.     

Thromboembolism after COVID-19 vaccine in patients with preexisting thrombocytopenia

While vaccination is the single most effective intervention to drastically reduce severe disease and death following SARS-CoV-2 infection, as shown in UK and Israel, some serious concerns have been raised for an unusual adverse drug reaction (ADR), including vaccine-induced immune thrombotic thrombocytopenia (VITT) with concurrent low platelets as well as capillary leak syndrome. In fact, the overall safety of the vaccine is highlighted by the low frequency of ADR considering that in UK, by the early June, 40 million first doses and 29 million second doses have been injected; nonetheless, 390 thrombotic events, including 71 fatal events have been reported. Interestingly, the cases reported low platelet counts with the presence of anti-platelet factor-4 (PF4) antibodies, indicating an abnormal clotting reaction. Here, out of three referred cases, we report a post-vaccine clinical case of fatal thrombosis with postmortem examination and whole exome sequencing (WES) analysis, whose pathogenesis appeared associated to a preexisting condition of thrombocytopenia due to myelodysplasia.Subject terms: Diseases, Medical research     

Cryptic diversity and diversification processes in three cis-Andean Rhamdia species (Siluriformes: Heptapteridae) revealed by DNA barcoding

The wide distribution of the Neotropical freshwater catfish Rhamdia offers an excellent opportunity to investigate the historical processes responsible for modeling South America’s hydrogeological structure. We used sequences from cis-Andean and Mesoamerican Rhamdia species to reconstruct and estimate divergence times among cis-Andean lineages, correlating the results with known geological events. Species delimitation methods based on distance (DNA barcoding and BIN) and coalescence (GMYC) approaches identified nine well-supported lineages from the cis-Andean region from sequences available in the BOLD dataset. The cis-Andean Rhamdia lineages diversification process began in Eocene and represented the split between cis-Andean and Mesoamerican clades. The cis-Andean clade contains two principal groups: Northwest clade (MOTUs from Amazon, Essequibo, Paraguay, and Itapecuru basins) and Southeast clade (Eastern Brazilian shield basins (Paraná, Uruguay, Iguaçu, and São Francisco) plus eastern coastal basins). The diversification of the cis-Andean Rhamdia lineages results from vicariance and geodispersion events, which played a key role in the current intricate distribution pattern of the Rhamdia lineages. The wide geographical distribution and large size of the specimens make it attractive to cultivate in different countries of the Neotropical region. The lineages delimitation minimizes identification mistakes, unintentional crossings by aquaculture, and reduces natural stocks contamination.     

In vitro activity of the hydroethanolic extract and biflavonoids isolated from Selaginella sellowii on Leishmania (Leishmania) amazonensis

This study is the first phytochemical investigation of Selaginella sellowii and demonstrates the antileishmanial activity of the hydroethanolic extract from this plant (SSHE), as well as of the biflavonoids amentoflavone and robustaflavone, isolated from this species. The effects of these substances were evaluated on intracellular amastigotes of Leishmania (Leishmania) amazonensis, an aetiological agent of American cutaneous leishmaniasis. SSHE was highly active against intracellular amastigotes [the half maximum inhibitory concentration (IC50) = 20.2 µg/mL]. Fractionation of the extract led to the isolation of the two bioflavonoids with the highest activity: amentoflavone, which was about 200 times more active (IC50 = 0.1 μg/mL) and less cytotoxic than SSHE (IC50 = 2.2 and 3 μg/mL, respectively on NIH/3T3 and J774.A1 cells), with a high selectivity index (SI) (22 and 30), robustaflavone, which was also active against L. amazonensis (IC50 = 2.8 µg/mL), but more cytotoxic, with IC50 = 25.5 µg/mL (SI = 9.1) on NIH/3T3 cells and IC50 = 3.1 µg/mL (SI = 1.1) on J774.A1 cells. The production of nitric oxide (NO) was lower in cells treated with amentoflavone (suggesting that NO does not contribute to the leishmanicidal mechanism in this case), while NO release was higher after treatment with robustaflavone. S. sellowii may be a potential source of biflavonoids that could provide promising compounds for the treatment of cutaneous leishmaniasis.     

Prevalence and genetic characterisation of HTLV-1 and 2 dual infections in patients with pulmonary tuberculosis in Central-West Brazil

Human T-cell lymphotropic virus (HTLV) may impact the clinical course of tuberculosis (TB). Both infections are highly endemic in Brazil. The aim of this study was to assess the prevalence of HTLV-1/2 in TB patients in Central-West Brazil and to perform a genetic characterisation of the respective isolates. Of the 402 patients, six (1.49%) were positive for anti-HTLV and five (1.24%; 95% confidence interval: 0.46-3.05) were infected with HTLV-1/2. Genetic characterisation demonstrated that the four HTLV-1 isolates belonged to the Transcontinental subgroup A of the Cosmopolitan subtype a and that the HTLV-2 isolate belonged to subtype a (HTLV-2a/c). The prevalence of HTLV infection observed in this study is higher than that observed in local blood donors and the HTLV-1 and 2 subtypes identified are consistent with those circulating in Brazil.     

Mixed-Species Biofilms Cultured from an Oil Sand Tailings Pond can Biomineralize Metals

Here, we used an in vitro biofilm approach to study metal resistance and/or tolerance of mixed-species biofilms grown from an oil sand tailings pond in northern Alberta, Canada. Metals can be inhibitory to microbial hydrocarbon degradation. If microorganisms are exposed to metal concentrations above their resistance levels, metabolic activities and hydrocarbon degradation can be slowed significantly, if not inhibited completely. For this reason, bioremediation strategies may be most effective if metal-resistant microorganisms are used. Viability was measured after exposure to a range of concentrations of ions of Cu, Ag, Pb, Ni, Zn, V, Cr, and Sr. Mixed-species biofilms were found to be extremely metal resistant; up to 20 mg/L of Pb, 16 mg/L of Zn, 1,000 mg/L of Sr, and 3.2 mg/L of Ni. Metal mineralization was observed by visualization with scanning electron microscopy with metal crystals of Cu, Ag, Pb, and Sr exuding from the biofilms. Following metal exposure, the mixed-species biofilms were analyzed by molecular methods and were found to maintain high levels of species complexity. A single species isolated from the community (Rhodococcus erythropolis) was used as a comparison against the mixed-community biofilm and was seen to be much less tolerant to metal stress than the community and did not biomineralize the metals.     

Oleic acid induces intracellular calcium mobilization, MAPK phosphorylation, superoxide production and granule release in bovine neutrophils

Oleic acid (OA) is a nonesterified fatty acid that is released into the blood during lipomobilization at the time of calving in cows, a period where increased risk of infection and acute inflammation is observed. These data suggest potential OA-mediated regulation of innate immune responses. In the present study, we assessed the effects of OA on intracellular calcium release, ERK1/2 phosphorylation, superoxide production, CD11b expression and matrix metalloproteinase-9 (MMP-9) release in bovine neutrophils. Furthermore, the presence of GPR40, an OA receptor, was assessed by RT-PCR, immunoblotting and confocal microscopy. OA induced, in a dose-dependent manner, intracellular calcium mobilization, superoxide production and CD11b expression in bovine neutrophils; these effects were reduced by the intracellular chelating agent BAPTA-AM. OA also induced ERK2 phosphorylation and MMP-9 release. RT-PCR analysis detected mRNA expression of a bovine ortholog of the GPR40 receptor. Using a polyclonal antibody against human GPR40, we detected a protein of 31 kDa by immunoblotting that was localized predominately in the plasma membrane. The selective agonist of GPR40, GW9508, induced intracellular calcium mobilization and ERK2 phosphorylation. In conclusion, OA can modulate bovine neutrophil responses in an intracellular calcium-dependent manner; furthermore, these responses could be induced by GPR40 activation.