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In vitro cellular models provide valuable insights into the adaptive biochemical mechanisms triggered by cells to cope with the stress situation induced by hypoxia and reoxygenation cycles. The first biological data generated in studies based on this micrometric life-scale has the potential to provide us a global overview about the main biochemical phenomena presented in some reported preconditioning therapies in life-scale of higher dimensions. Thus, in this study, a cell incubator was designed and manufactured to produce a cellular model of heart hypoxia followed by reoxygenation (HfR) through consecutive repetitions of hypoxia-normoxia gas exchange. Samples of cellular extracts and culture media were obtained from non-proliferative cardiomyocytes (CMs) cultivated under challenging HfR (stressed CMs) and regular cultivation (unstressed CMs) in rounds of four days for each case. Metabolomic based on proton magnetic resonance spectroscopy ( 1 H-MRS) was used as an analytical approach to identify and quantify the metabolomes of these samples, the endo- and exo-metabolome. Despite the stressed CMs presented over 90% higher cellular death rate compared to the unstressed CMs, the metabolic profiles indicates that the surviving cells up-regulate their amino acid metabolism either by active protein degradation or by the consumption of culture media components to increase coenzyme A-dependent metabolic pathways. This cell auto-regulation mechanism could be well characterized in the first two days when the difference smears off under once the metabolomes become similar. The metabolic adaptations of stressed CMs identified the relevance of the cyclic oxidation/reduction reactions of nicotinamide adenine dinucleotide phosphate molecules, NADP + /NADPH, and the increased tricarboxylic acid cycle activity in an environment overloaded with such a powerful antioxidant agent to survive an extreme HfR challenge. Thus, the combination of cellular models based on CMs, investigative methods, such as metabolomic and 1 H-MRS, and the instrumental development of hypoxia incubator shown in this work were able to provide the first biochemical evidences behind therapies of gaseous exchanges paving the way to future assays., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

The interaction between silver nanoparticles (AgNPs) and molecules producing coronas plays a key role in cytotoxicity mechanisms. Once adsorbed coronas determine the destiny of nanomaterials in vivo, their effective deployment in the biomedical field requires a comprehensive understanding of the dynamic interactions of biomolecules with nanoparticles. In this work, we characterized 40 nm AgNPs in three different nutritional cell media at different molar concentrations and incubation times to study the binding mechanism of molecules on surface nanoparticles. In addition, their cytotoxic effects have been studied in three cell lineages used as tissue regeneration models: FN1, HUV-EC-C, RAW 264.7. According to the data, when biomolecules from DMEM medium were in contact with AgNPs, agglomeration and precipitation occurred. However, FBS medium proteins indicated the formation of coronas over the nanoparticles. Nonetheless, little adsorption of molecules around the nanoparticles was observed when compared to DMEM supplemented with 10% FBS. These findings indicate that when nanoparticles and bioproteins from supplemented media interact, inorganic salts from DMEM contribute to produce large bio-coronas, the size of which varies with the concentration and time. The static quenching mechanism was shown to be responsible for the fluorescence quenching of the bioprotein aggregates on the AgNPs surface. The calculated bioprotein-nanoparticle surface binding constants were on the order of 10 5  M -1 at 37 °C, with hydrophobic interactions driven by enthalpy and entropy playing a role, as confirmed by thermodynamic analysis. Cytotoxicity data showed a systematic degrowth in the viable cell population as the number of nanoparticles increased and the diameter of coronas decreased. Cytotoxic intervals associated with half decrease of cell population were established for AgNPs molar concentration of 75 µM for 24 h and 50 µM for 48 h. In summary, through the cytotoxicity mechanism of bio-coronas we are able to manipulate cells' expansion rates to promote specific processes, such inflammatory mechanisms, at different time instants., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: The United Nations Children's Fund (UNICEF) published their Health Systems Strengthening (HSS) approach to meet its strategic goals of ending preventable maternal, newborn and child deaths and promoting the health and development of all children and reducing inequities in health in 2016. UNICEF commissioned the University of Melbourne's Nossal Institute for Global Health to develop and deliver a pilot blended HSS program, involving 60 hours of online learning and 2 weeks of face-to-face teaching over a 6-month period. To assess the extent to which the HSS program had built the first 83 UNICEF 2017 graduates' capabilities to apply HSS actions by 2017, UNICEF funded an independent evaluator from the University of Melbourne., Methods: A mixed-methods assessment was conducted using: online surveys of graduates at: enrolment, completion, 6 months post-HSS program; nine focus groups with graduates at face-to-face workshops; and interviews with purposive samples of UNICEF graduates and graduate Senior Managers 12 months post-HSS program., Results: The HSS program content, structure and mode of delivery was positively received. Graduates reported increased confidence taking HSS actions and multiple changes in work practices (e.g., increased systems thinking and using of health system-based approaches). Graduates' Senior Manager interviews revealed mixed impressions of graduates applying HSS actions, partly explained by the fit between the HSS program learnings and UNICEF's workplace environment. Key contextual factors influencing graduates applying HSS actions included: workload; limited opportunities to apply HSS actions; limited HSS examples; and variable support to apply HSS actions. Graduate and Senior Manager suggestions to optimise applying HSS actions included: linking HSS program content with UNICEF priorities; increasing opportunities for graduates to apply HSS actions; increasing access to HSS support., Conclusions: The paper concludes by presenting HSS program and assessment suggestions from the 2017 UNICEF Pilot HSS program assessment and actions taken for the 2018 UNICEF staff cohorts by HSS program developers, funders and beneficiaries.

Forest loss and fragmentation are the main threats to the maintenance of the Atlantic Forest, an important global biodiversity hotspot. Because of the current critical level of deforestation, ecological corridors are needed to facilitate species dispersion and gene flow among fragments. This study was conducted to investigate the genetic variability and gene pool sharing of Eschweilera ovata in five forest remnants in southern Bahia, Brazil using nuclear simple sequence repeat (nSSR) and plastid simple sequence repeat (cpSSR) microsatellite markers. cpSSR marker analysis revealed the domains of four haplotypes, showing that 80% of the individuals had only four maternal origins, reflecting a founder effect and/or genetic bottleneck. The results of cpSSR and nSSR analyses indicated moderate genetic diversity, particularly in conservation units with full protection, which showed the best parameters of all areas evaluated. Another indication of the susceptibility of these populations to forest loss and fragmentation was the strong genetic bottleneck observed. In contrast, genetic structure analyses (FST and discriminant analysis of principal components) revealed gene pool sharing between the subpopulations, which may reflect the historical gene flow that occurred before forest fragmentation.

The Atlantic Forest is a phytogeographic domain with a high rate of endemism and large species diversity. The Sapotaceae is a botanical family for which species identification in the Atlantic Forest is difficult. An approach that facilitates species identification in the Sapotaceae is urgently needed because this family includes threatened species and valuable timber species. In this context, DNA barcoding could provide an important tool for identifying species in the Atlantic Forest. In this work, we evaluated four plant barcode markers (matK, rbcL, trnH-psbA and the nuclear ribosomal internal transcribed spacer region - ITS) in 80 samples from 26 species of Sapotaceae that occur in the Atlantic Forest. ITS yielded the highest average interspecific distance (0.122), followed by trnH-psbA (0.019), matK (0.008) and rbcL (0.002). For species discrimination, ITS provided the best results, followed by matK, trnH-psbA and rbcL. Furthermore, the combined analysis of two, three or four markers did not result in higher rates of discrimination than obtained with ITS alone. These results indicate that the ITS region is the best option for molecular identification of Sapotaceae species from the Atlantic Forest.

Manilkara multifida is a tropical tree that is endemic to the Atlantic forests of southern Bahia, Brazil. Currently, populations of this species are restricted to fragmented landscapes that are susceptible to anthropogenic disturbances. Considering this issue, and that there is no genetic information available for this endangered species, we developed microsatellite markers for M. multifida to provide resources for future conservation genetics studies. Using an enriched genomic library, we isolated eight polymorphic microsatellite loci and optimized the amplification conditions for M. multifida. For each locus, we estimated the number of alleles, H E and H O, paternity exclusion Q, individual identity I and fixation index F, and examined the presence of null alleles. The mean number of alleles was 11.9, and the heterozygosity was high at all loci (average H E = 0.809 and H O = 0.777). The combined values for both paternity exclusion and individual identity were Q = 0.9959 and I = 5.45 × 10(-11), respectively. No evidence of null alleles was detected. The results of our analysis indicated that all eight microsatellites are promising for assessing questions involving inbreeding, gene flow, co-ancestry and mating patterns in M. multifida.

To provide vaccination against infection due to 2009 pandemic influenza A virus subtype H1N1 (A[H1N1]pdm09) to resource-constrained countries with otherwise very little access to the A(H1N1)pdm09 vaccine, the World Health Organization (WHO) coordinated distribution of donated vaccine to selected countries worldwide, including those in Africa. From February through November 2010, 32.2 million doses were delivered to 34 countries in Africa. Of the 19.2 million doses delivered to countries that reported their vaccination activities to WHO, 12.2 million doses (64%) were administered. Population coverage in these countries varied from 0.4% to 11%, with a median coverage of 4%. All countries targeted pregnant women (median proportion of all vaccine doses administered [mpv], 21% [range, 4%-72%]) and healthcare workers (mpv, 9% [range, 1%-73%]). Fourteen of 19 countries targeted persons with chronic conditions (mpv, 26% [range, 5%-66%]) and 10 of 19 countries vaccinated children (mpv, 54% [range, 17%-75%]). Most vaccine was distributed after peak A(H1N1)pdm09 transmission in the region. The frequency and severity of adverse events were consistent with those recorded after other inactivated influenza vaccines. Pandemic preparedness plans will need to include strategies to ensure more-rapid procedures to identify vaccine supplies and distribute and import vaccines to countries that may bear the brunt of a future pandemic.

Melanoxylon brauna (Fabaceae - Caesalpinioideae) is an endemic and valuable hardwood tree species in the Brazilian Atlantic rainforest; it is comparable to African ebony wood. We tested three protocols of DNA extraction based on the citrimonium bromide (CTAB) method and evaluated the quantity, purity and integrity of the DNA. We also determined whether these procedures interfere with PCR amplification in order to develop a protocol for M. brauna. We found that the quality and integrity of DNA were improved with the use of proteinase K in the extraction buffer and by modifications in the centrifugation speed. The lowest concentration of DNA was obtained with Doyle and Doyle's protocol (5.42 ng/μL). Ferreira and Grattapaglia's protocol modified for M. brauna provided the most DNA (36.89 ng/μL) and the highest quality DNA (purity ratio of 1.80 nm). The original Ferreira and Grattapaglia protocol provided 13.42 ng/μL DNA; however, the purity ratio (1.44 nm) indicates protein contamination. PCR results showed that Ferreira and Grattapaglia's protocol modified for M. brauna gave satisfactory quantity and purity of DNA for molecular studies.