Hematological parameters of red tilapia (Oreochromis sp.) fed lemongrass essential oil (Cymbopogon citratus) after challenge with Streptococcus agalactiae

The study involved feeding lemongrass essential oil (LEO) supplements to red tilapia (Oreochromis sp.) at concentrations including Control - 0 mg, T1 – 200 mg, T2 – 300 mg, and T3 – 400 mg per kg of feed. The research investigated changes in hematological (HCT, Hb, RBC, WBC & thrombocytes) and erythrocyte’s morphological (major/minor axis; perimeter, and area of erythrocyte) parameters before infection, 5- and 10-days post-infection (DPI). According to analytical findings, a diet containing LEO enhanced the synthesis of both erythrocytes and leukocytes in the peripheral blood of red tilapia after 20 days of being used. Therefore, the indicators of this group of fish showed better performance than those that did not use LEO supplement five days after bacterial infection. Fish fed 200 mg/kg of LEO after being challenged with S. agalactiae for ten days showed an improved effect on red blood cell production. White blood cells decreased at all concentrations because of citral’s immunomodulatory properties

Structure, magnetism, and magnetocaloric properties of MnFeP1−xSix compounds

MnFeP1-xSix compounds with x=0.10,0.20,0.24,0.28,...,0.80,1 were prepared by high-energy ball milling and solid-state reaction. The structural, magnetic, and magnetocaloric properties are investigated as a function of temperature and magnetic field. X-ray diffraction studies show that the samples in the range from x=0.28 to 0.64 adopt the hexagonal Fe2P-type structure with a small amount of second phase which increases with increasing Si content. The samples with lower Si content show the orthorhombic Co2P-type structure. Magnetic measurements show that the paramagnetic-ferromagnetic transition temperatures range from 214 to 377 K. Of much importance is the fact that these compounds do not contain any toxic components and exhibit excellent magnetocaloric properties

Clinical features, antimicrobial susceptibility patterns and genomics of bacteria causing neonatal sepsis in a children's hospital in Vietnam: protocol for a prospective observational study.

INTRODUCTION: The clinical syndrome of neonatal sepsis, comprising signs of infection, septic shock and organ dysfunction in infants ≤4 weeks of age, is a frequent sequel to bloodstream infection and mandates urgent antimicrobial therapy. Bacterial characterisation and antimicrobial susceptibility testing is vital for ensuring appropriate therapy, as high rates of antimicrobial resistance (AMR), especially in low-income and middle-income countries, may adversely affect outcome. Ho Chi Minh City (HCMC) in Vietnam is a rapidly expanding city in Southeast Asia with a current population of almost 8 million. There are limited contemporary data on the causes of neonatal sepsis in Vietnam, and we hypothesise that the emergence of multidrug resistant bacteria is an increasing problem for the appropriate management of sepsis cases. In this study, we aim to investigate the major causes of neonatal sepsis and assess disease outcomes by clinical features, antimicrobial susceptibility profiles and genome composition. METHOD AND ANALYSIS: We will conduct a prospective observational study to characterise the clinical and microbiological features of neonatal sepsis in a major children's hospital in HCMC. All bacteria isolated from blood subjected to whole genome sequencing. We will compare clinical variables and outcomes between different bacterial species, genome composition and AMR gene content. AMR gene content will be assessed and stratified by species, years and contributing hospital departments. Genome sequences will be analysed to investigate phylogenetic relationships. ETHICS AND DISSEMINATION: The study will be conducted in accordance with the principles of the Declaration of Helsinki and the International Council on Harmonization Guidelines for Good Clinical Practice. Ethics approval has been provided by the Oxford Tropical Research Ethics Committee 35-16 and Vietnam Children's Hospital 1 Ethics Committee 73/GCN/BVND1. The findings will be disseminated at international conferences and peer-reviewed journals. TRIAL REGISTRATION NUMBER: ISRCTN69124914; Pre-results

Mg-modified Zn-Co-Fe-La nano ferrites: a study of structural, morphological, vibrational, electro-optical, dielectric and magnetic evolution

The series of Zn0.4Co0.6−xMgxFe1.9La0.1O4 (x = 0.0, 0.15, 0.30, 0.45, 0.6) nanoferrites prepared via co-precipitation technique. Scherrer and Williamson-Hall (W-H) methods were used to find the crystallite size (29.6–39.2 nm and 31.6–36.3 nm, respectively) and lattice constant was calculated (8.406–8.395 Å). Moreover, Fourier transform infrared (FTIR) spectroscopy revealed the existence of absorption bands along with functional groups. The vibrations of O2- ions at the tetrahedral and octahedral sites were shown by the Raman five active modes. DC resistivity reduced in the range of 5.2961 × 108 Ω cm to 9.6453 × 107 Ω cm for x = 0.0 to x = 0.6, respectively. The maximum DC resistivity and activation energy (0.1035 eV) were obtained at the parent sample (Zn0.4Co0.6Fe1.9La0.1O4). The optical bandgaps reduced from 2.61 to 1.47 eV, as the Mg2+ contents increased. With increasing frequency the dielectric loss and the dielectric constant decrease. The magnetic parameters such as saturation magnetization (Ms = 60.82–25.94 emu/g), remnant magnetization (Mr = 47.82–18.64 emu/g), and coercivity (Hc = 1334–511 Oe) demonstrated reducing trends with the increase of Mg2+ doping. The best magnetic behavior of the as-prepared samples suitable in microwave devices was observed for Zn0.4Co0.6Fe1.9La0.1O4 sample

Synthetic prions with novel strain-specified properties

Prions are infectious proteins that possess multiple self-propagating structures. The information for strains and structural specific barriers appears to be contained exclusively in the folding of the pathological isoform, PrP(Sc). Many recent studies determined that de novo prion strains could be generated in vitro from the structural conversion of recombinant (rec) prion protein (PrP) into amyloidal structures. Our aim was to elucidate the conformational diversity of pathological recPrP amyloids and their biological activities, as well as to gain novel insights in characterizing molecular events involved in mammalian prion conversion and propagation. To this end we generated infectious materials that possess different conformational structures. Our methodology for the prion conversion of recPrP required only purified rec full-length mouse (Mo) PrP and common chemicals. Neither infected brain extracts nor amplified PrP(Sc) were used. Following two different in vitro protocols recMoPrP converted to amyloid fibrils without any seeding factor. Mouse hypothalamic GT1 and neuroblastoma N2a cell lines were infected with these amyloid preparations as fast screening methodology to characterize the infectious materials. Remarkably, a large number of amyloid preparations were able to induce the conformational change of endogenous PrPC to harbor several distinctive proteinase-resistant PrP forms. One such preparation was characterized in vivo habouring a synthetic prion with novel strain specified neuropathological and biochemical properties

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century