A novel malaria mathematical model: integrating vector and non-vector transmission pathways.

Background: Malaria remains one of the most significant global health challenges, particularly in tropical and subtropical regions. Despite ongoing control efforts, malaria transmission persists due to complex biological, environmental, and socio-economic factors. Traditional malaria models have primarily focused on vector-borne transmission, overlooking the growing importance of non-vector transmission pathways, such as blood transfusions, congenital transmission, and human-to-human transmission through healthcare settings.

Ammonia synthesis via an engineered nitrogenase assembly pathway in .

Heterologous expression of nitrogenase has been actively pursued because of the far-reaching impact of this enzyme on agriculture, energy and environment. Yet, isolation of an active two-component, metallocentre-containing nitrogenase from a non-diazotrophic host has yet to be accomplished. Here, we report the heterologous synthesis of an active Mo-nitrogenase by combining genes from and in .

The impact of parental and developmental stress on DNA methylation in the avian hypothalamic-pituitary-adrenal axis.

The hypothalamic-pituitary-adrenal (HPA) axis coordinates an organism's response to environmental stress. The responsiveness and sensitivity of an offspring's stress response may be shaped not only by stressors encountered in their early post-natal environment but also by stressors in their parent's environment. Yet, few studies have considered how stressors encountered in both of these early life environments may function together to impact the developing HPA axis.

Heterologous expression of a fully active nitrogenase Fe protein in .

The heterologous expression of a fully active Fe protein (AvNifH) has never been accomplished. Given the functional importance of this protein in nitrogenase catalysis and assembly, the successful expression of AvNifH in as reported herein supplies a key element for the further development of heterologous expression systems that explore the catalytic versatility of the Fe protein, either on its own or as a key component of nitrogenase, for nitrogenase-based biotechnological applications in the future. Moreover, the "clean" genetic background of the heterologous expression host allows for an unambiguous assessment of the effect of certain nif-encoded protein factors, such as AvNifM described in this work, in the maturation of AvNifH, highlighting the utility of this heterologous expression system in further advancing our understanding of the complex biosynthetic mechanism of nitrogenase.

Heterologous synthesis of the complex homometallic cores of nitrogenase P- and M-clusters in .

Nitrogenase is an active target of heterologous expression because of its importance for areas related to agronomy, energy, and environment. One major hurdle for expressing an active Mo-nitrogenase in is to generate the complex metalloclusters (P- and M-clusters) within this enzyme, which involves some highly unique bioinorganic chemistry/metalloenzyme biochemistry that is not generally dealt with in the heterologous expression of proteins via synthetic biology; in particular, the heterologous synthesis of the homometallic P-cluster ([FeS]) and M-cluster core (or L-cluster; [FeSC]) on their respective protein scaffolds, which represents two crucial checkpoints along the biosynthetic pathway of a complete nitrogenase, has yet to be demonstrated by biochemical and spectroscopic analyses of purified metalloproteins. Here, we report the heterologous formation of a P-cluster-containing NifDK protein upon coexpression of , , , and genes, and that of an L-cluster-containing NifB protein upon coexpression of , and genes alongside the gene, in .

Epigenetic modification of the hypothalamic-pituitary-adrenal (HPA) axis during development in the house sparrow (Passer domesticus).

Epigenetic modifications such as DNA methylation are important mechanisms for mediating developmental plasticity, where ontogenetic processes and their phenotypic outcomes are shaped by early environments. In particular, changes in DNA methylation of genes within the hypothalamic-pituitary-adrenal (HPA) axis can impact offspring growth and development. This relationship has been well documented in mammals but is less understood in other taxa.

Target-enriched enzymatic methyl sequencing: Flexible, scalable and inexpensive hybridization capture for quantifying DNA methylation.

The increasing interest in studying DNA methylation to understand how traits or diseases develop requires new and flexible approaches for quantifying DNA methylation in a diversity of organisms. In particular, we need efficient yet cost-effective ways to measure CpG methylation states over large and complete regions of the genome. Here, we develop TEEM-Seq (target-enriched enzymatic methyl sequencing), a method that combines enzymatic methyl sequencing with a custom-designed hybridization capture bait set that can be scaled to reactions including large numbers of samples in any species for which a reference genome is available.

Enzymatic Fischer-Tropsch-Type Reactions.

The Fischer-Tropsch (FT) process converts a mixture of CO and H into liquid hydrocarbons as a major component of the gas-to-liquid technology for the production of synthetic fuels. Contrary to the energy-demanding chemical FT process, the enzymatic FT-type reactions catalyzed by nitrogenase enzymes, their metalloclusters, and synthetic mimics utilize H and e as the reducing equivalents to reduce CO, CO, and CN into hydrocarbons under ambient conditions. The C chemistry exemplified by these FT-type reactions is underscored by the structural and electronic properties of the nitrogenase-associated metallocenters, and recent studies have pointed to the potential relevance of this reactivity to nitrogenase mechanism, prebiotic chemistry, and biotechnological applications.

Nitrogenase Fe Protein: A Multi-Tasking Player in Substrate Reduction and Metallocluster Assembly.

The Fe protein of nitrogenase plays multiple roles in substrate reduction and metallocluster assembly. Best known for its function to transfer electrons to its catalytic partner during nitrogenase catalysis, the Fe protein is also a key player in the biosynthesis of the complex metalloclusters of nitrogenase. In addition, it can function as a reductase on its own and affect the ambient reduction of CO or CO to hydrocarbons.

Incorporation of an Asymmetric Mo-Fe-S Cluster as an Artificial Cofactor into Nitrogenase.

Nitrogenase employs a sophisticated electron transfer system and a Mo-Fe-S-C cofactor, designated the M-cluster [(cit)MoFe S C]), to reduce atmospheric N to bioaccessible NH . Previously, we have shown that the cofactor-free form of nitrogenase can be repurposed as a protein scaffold for the incorporation of a synthetic Fe-S cluster [Fe S (SEt) ] . Here, we demonstrate the utility of an asymmetric Mo-Fe-S cluster [Cp*MoFe S (SH)] as an alternative artificial cofactor upon incorporation into the cofactor-free nitrogenase scaffold.

Radical SAM-dependent formation of a nitrogenase cofactor core on NifB.

Nitrogenase is a versatile metalloenzyme that reduces N, CO and CO at its cofactor site. Designated the M-cluster, this complex cofactor has a composition of [(R-homocitrate)MoFeSC], and it is assembled through the generation of a unique [FeSC] core prior to the insertion of Mo and homocitrate. NifB is a radical S-adenosyl-L-methionine (SAM) enzyme that is essential for nitrogenase cofactor assembly.

Probing the All-Ferrous States of Methanogen Nitrogenase Iron Proteins.

The Fe protein of nitrogenase reduces two C1 substrates, CO and CO, under ambient conditions when its [FeS] cluster adopts the all-ferrous [FeS] state. Here, we show disparate reactivities of the - and -encoded Fe proteins from (designated NifH and VnfH) toward C1 substrates in the all-ferrous state, with the former capable of reducing both CO and CO to hydrocarbons, and the latter only capable of reducing CO to hydrocarbons at substantially reduced yields. EPR experiments conducted at varying solution potentials reveal that VnfH adopts the all-ferrous state at a more positive reduction potential than NifH, which could account for the weaker reactivity of the VnfH toward C1 substrates than NifH.

Feather Gene Expression Elucidates the Developmental Basis of Plumage Iridescence in African Starlings.

Iridescence is widespread in the living world, occurring in organisms as diverse as bacteria, plants, and animals. Yet, compared to pigment-based forms of coloration, we know surprisingly little about the developmental and molecular bases of the structural colors that give rise to iridescence. Birds display a rich diversity of iridescent structural colors that are produced in feathers by the arrangement of melanin-containing organelles called melanosomes into nanoscale configurations, but how these often unusually shaped melanosomes form, or how they are arranged into highly organized nanostructures, remains largely unknown.

Heterologous Expression and Engineering of the Nitrogenase Cofactor Biosynthesis Scaffold NifEN.

NifEN plays a crucial role in the biosynthesis of nitrogenase, catalyzing the final step of cofactor maturation prior to delivering the cofactor to NifDK, the catalytic component of nitrogenase. The difficulty in expressing NifEN, a complex, heteromultimeric metalloprotein sharing structural/functional homology with NifDK, is a major challenge in the heterologous expression of nitrogenase. Herein, we report the expression and engineering of Azotobacter vinelandii NifEN in Escherichia coli.

Crystal structure of 3-[(2-acetamido-phen-yl)imino]-butan-2-one.

In the title compound, 3-[(2-acetamido-phen-yl)imino]-butan-2-one, CHNO, the imine C=N bond is essentially coplanar with the ketone C=O bond in an conformation. The benzene ring is twisted away from the plane of the C=N bond by 53.03 (14)°.

iPhone Sensors in Tracking Outcome Variables of the 30-Second Chair Stand Test and Stair Climb Test to Evaluate Disability: Cross-Sectional Pilot Study.

Background: Performance tests are important to characterize patient disabilities and functional changes. The Osteoarthritis Research Society International and others recommend the 30-second Chair Stand Test and Stair Climb Test, among others, as core tests that capture two distinct types of disability during activities of daily living. However, these two tests are limited by current protocols of testing in clinics.

Cardiovascular risk factors and hearing loss among adults in a tertiary center of Northwestern Nigeria.

Objective: To assess the effect of cardiovascular risk factors on hearing impairment.

Methods: This was a cross sectional study conducted in Usmanu Danfodiyo University Teaching Hospital, Sokoto. A pretested questionnaire was used to obtain information about the biodata and medical history of participants after which, they were examined and had their hearing thresholds measured.

Transformation of Metal-Organic Framework Secondary Building Units into Hexanuclear Zr-Alkyl Catalysts for Ethylene Polymerization.

We report the stepwise and quantitative transformation of the Zr(μ-O)(μ-OH)(HCO) nodes in Zr-BTC (MOF-808) to the [Zr(μ-O)(μ-OH)Cl] nodes in ZrCl-BTC, and then to the organometallic [Zr(μ-O)(μ-OLi)R] nodes in ZrR-BTC (R = CHSiMe or Me). Activation of ZrCl-BTC with MMAO-12 generates ZrMe-BTC, which is an efficient catalyst for ethylene polymerization. ZrMe-BTC displays unusual electronic and steric properties compared to homogeneous Zr catalysts, possesses multimetallic active sites, and produces high-molecular-weight linear polyethylene.

Development of genome- and transcriptome-derived microsatellites in related species of snapping shrimps with highly duplicated genomes.

Molecular markers are powerful tools for studying patterns of relatedness and parentage within populations and for making inferences about social evolution. However, the development of molecular markers for simultaneous study of multiple species presents challenges, particularly when species exhibit genome duplication or polyploidy. We developed microsatellite markers for Synalpheus shrimp, a genus in which species exhibit not only great variation in social organization, but also interspecific variation in genome size and partial genome duplication.

Assessment of myocardial injury after reperfused infarction by T1ρ cardiovascular magnetic resonance.

Background: The evolution of T1ρ and of other endogenous contrast methods (T2, T1) in the first month after reperfused myocardial infarction (MI) is uncertain. We conducted a study of reperfused MI in pigs to serially monitor T1ρ, T2 and T1 relaxation, scar size and transmurality at 1 and 4 weeks post-MI.

Methods: Ten Yorkshire swine underwent 90 min of occlusion of the circumflex artery and reperfusion.

Sex-specific fitness effects of unpredictable early life conditions are associated with DNA methylation in the avian glucocorticoid receptor.

Organisms can adapt to variable environments by using environmental cues to modulate developmental gene expression. In principle, maternal influences can adaptively adjust offspring phenotype when early life and adult environments match, but they may be maladaptive when future environments are not predictable. One of the best-studied 'maternal effects' is through modification of the offspring's hypothalamic-pituitary-adrenal (HPA) axis, the neuroendocrine system that controls responses to stress.

A comparison of single nucleotide polymorphism and microsatellite markers for analysis of parentage and kinship in a cooperatively breeding bird.

The development of genetic markers has revolutionized molecular studies within and among populations. Although poly-allelic microsatellites are the most commonly used genetic marker for within-population studies of free-living animals, biallelic single nucleotide polymorphisms, or SNPs, have also emerged as a viable option for use in nonmodel systems. We describe a robust method of SNP discovery from the transcriptome of a nonmodel organism that resulted in more than 99% of the markers working successfully during genotyping.