The use of Aloe barbadensis M. (Aloe vera) Extract as Potential Stains in Gram’s Staining Technique

Aloe barbadensis miller (Aloe vera) aside being a potent antioxidant with effects attributed to the phytoconstituents (anthraquinone), can also serve as natural dyes. This study explored the staining potentials of A. barbadensis extract on microbial specimens in modified Gram’s staining technique. The plant was washed; shrubby edges of the leaves were scraped off and each leaf cut open to expel the gel content. The dried and grinded leaf material weighing 450g was treated with two different extraction methods (150g for heated alcoholic aloe extract (HAAE) and 150g each for the unheated alcoholic aloe extracts I & II (UAAE-1 & UAAE-II). Preliminary phytochemical screening of extracts using bontragers test was conducted. Solutions from the two extraction methods with and without a mordant were applied on bacterial smears. Anthraquinone-rich extract under optimal extraction conditions were 10.0, 4.84 and 18.8 respectively. Comparing the extraction methods, HAAE and UAAE1 & UAAEII are mutually convenient and easy to make; but the former was more cost-effective with regards to power and instrumentation while the latter was more cost-efficient with regards to solvent. The pH of various prepared solutions was acidic and the extracts contained a bioactive agent that imparts pigment on biological specimens. In comparing the mordanted and non-mordanted solutions, the former had no additional effects on the staining efficiency of the aloe dye extract. We concluded that A. barbadensis dye visibly stained bacterial Gram positive and Gram negative cells in modified Gram’s staining without structural differentiations. We recommend reductions in staining duration for microbial samples to ascertain the reasons for the variation in staining uptake

Prevalence and antibiotic resistance profiles of extended spectrum β-lactamase-producing Escherichia coli among paediatric patients with urinary tract infection in St. Patricks’ Hospital, Mile Four, Abakaliki, Ebonyi State, Nigeria

Background: The extended spectrum beta-lactamase (ESBL)-producing Escherichia coli strains which have been implicated in septicaemia among hospitalized children is a serious concern due to their high resistance rates to commonly used antimicrobial agents. The objective of this study was to determine the prevalence and antibiotic susceptibility of urinary ESBL-producing E. coli in paediatric patients who had clinical evidence of urinary tract infections (UTI).Methodology: Clean catch specimens of urine collected from 100 eligible paediatric patients with clinical evidence of UTI in St. Patricks’ Hospital, Mile Four, Abakaliki, Ebonyi State, were cultured for isolation of E. coli using standard bacteriological techniques. Isolates were confirmed for ESBL production by double disk synergy test (DDST), and antibiotic susceptibility of the ESBL-producing ones was determined by the modified Kirby Bauer disk diffusion method.Results: Twenty one (21%) E. coli were isolated out of which 11 (52 %) were ESBL producers, all of which were totally resistant (100%) to cefotaxime, ticarcillin and sulfamethoxazole-trimethoprim, 85% to aztreonam and 83% to ceftazidime. The multiple antibiotic resistance index (MARI) values ranged from 0.4 to 0.9, which implies high usage of antimicrobialsConclusion: The high prevalence of multi-drug resistant ESBL-producing E. coli obtained in this study shows that there has been overuse (abuse or misuse) of antibiotics in the study area. There is need for antimicrobial stewardship programme that will ensure prudent use of antimicrobial agents to forestall the emergence and spread of multi-drug resistant bacteria.Keywords: Paediatrics, Escherichia coli, ESBL, urine, multi-drug resistanc

Determination of the Fermi Velocity by Angle-dependent Periodic Orbit Resonance Measurements in the Organic Conductor alpha-(BEDT-TTF)2KHg(SCN)4

We report detailed angle-dependent studies of the microwave (f=50 to 90 GHz) interlayer magneto-electrodynamics of a single crystal sample of the organic charge-density-wave (CDW) conductor alpha-(BEDT-TTF)2KHg(SCN)4. Recently developed instrumentation enables both magnetic field (B) sweeps for a fixed sample orientation and, for the first time, angle sweeps at fixed f/B. We observe series' of resonant absorptions which we attribute to periodic orbit resonances (POR) - a phenomenon closely related to cyclotron resonance. The angle dependence of the POR indicate that they are associated with the low temperature quasi-one-dimensional (Q1D) Fermi surface (FS) of the title compound; indeed, all of the resonance peaks collapse beautifully onto a single set of f/B versus angle curves, generated using a semiclassical magneto-transport theory for a single Q1D FS. We show that Q1D POR measurements provide one of the most direct methods for determining the Fermi velocity, without any detailed assumptions concerning the bandstructure; our analysis yields an average value of v_F=6.5x10^4 m/s. Quantitative analysis of the POR harmonic content indicates that the Q1D FS is strongly corrugated. This is consistent with the assumption that the low-temperature FS derives from a reconstruction of the high temperature quasi-two-dimensional FS, caused by the CDW instability. Detailed analysis of the angle dependence of the POR yields parameters associated with the CDW superstructure which are consistent with published results. Finally, we address the issue as to whether or not the interlayer electrodynamics are coherent in the title compound.Comment: 28 pages, including 6 figures. Submitted to PR

The effect on melanoma risk of genes previously associated with telomere length.

Telomere length has been associated with risk of many cancers, but results are inconsistent. Seven single nucleotide polymorphisms (SNPs) previously associated with mean leukocyte telomere length were either genotyped or well-imputed in 11108 case patients and 13933 control patients from Europe, Israel, the United States and Australia, four of the seven SNPs reached a P value under .05 (two-sided). A genetic score that predicts telomere length, derived from these seven SNPs, is strongly associated (P = 8.92x10(-9), two-sided) with melanoma risk. This demonstrates that the previously observed association between longer telomere length and increased melanoma risk is not attributable to confounding via shared environmental effects (such as ultraviolet exposure) or reverse causality. We provide the first proof that multiple germline genetic determinants of telomere length influence cancer risk.This is the final version of the article. It first appeared from Oxford University Press via http://dx.doi.org/10.1093/jnci/dju26

Sexuality, disability, and reproductive issues through the lifespan

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45558/1/11195_2005_Article_BF01102578.pd

An Observational Overview of Solar Flares

We present an overview of solar flares and associated phenomena, drawing upon a wide range of observational data primarily from the RHESSI era. Following an introductory discussion and overview of the status of observational capabilities, the article is split into topical sections which deal with different areas of flare phenomena (footpoints and ribbons, coronal sources, relationship to coronal mass ejections) and their interconnections. We also discuss flare soft X-ray spectroscopy and the energetics of the process. The emphasis is to describe the observations from multiple points of view, while bearing in mind the models that link them to each other and to theory. The present theoretical and observational understanding of solar flares is far from complete, so we conclude with a brief discussion of models, and a list of missing but important observations.Comment: This is an article for a monograph on the physics of solar flares, inspired by RHESSI observations. The individual articles are to appear in Space Science Reviews (2011

Adherence to extended postpartum antiretrovirals is associated with decreased breast milk HIV-1 transmission

Estimate association between postpartum antiretroviral adherence and breastmilk HIV-1 transmissio

Para-infectious brain injury in COVID-19 persists at follow-up despite attenuated cytokine and autoantibody responses

To understand neurological complications of COVID-19 better both acutely and for recovery, we measured markers of brain injury, inflammatory mediators, and autoantibodies in 203 hospitalised participants; 111 with acute sera (1–11 days post-admission) and 92 convalescent sera (56 with COVID-19-associated neurological diagnoses). Here we show that compared to 60 uninfected controls, tTau, GFAP, NfL, and UCH-L1 are increased with COVID-19 infection at acute timepoints and NfL and GFAP are significantly higher in participants with neurological complications. Inflammatory mediators (IL-6, IL-12p40, HGF, M-CSF, CCL2, and IL-1RA) are associated with both altered consciousness and markers of brain injury. Autoantibodies are more common in COVID-19 than controls and some (including against MYL7, UCH-L1, and GRIN3B) are more frequent with altered consciousness. Additionally, convalescent participants with neurological complications show elevated GFAP and NfL, unrelated to attenuated systemic inflammatory mediators and to autoantibody responses. Overall, neurological complications of COVID-19 are associated with evidence of neuroglial injury in both acute and late disease and these correlate with dysregulated innate and adaptive immune responses acutely

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