IN VITRO EFFICACY TESTING OF NEEM (AZADIRACHTA INDICA) EXTRACT AGAINST AEROBIC AND ANAEROBIC BACTERIA

Objective: To experiment the antimicrobial susceptibility of crude extract from neem (Azadirachta indica) leaves against Staphylococcus aureus, Escherichia coli and Clostridium perfringens. Methods: Through the water extraction method, the aqueous crude extract of neem leaves were obtained. Separate colonies of Staphylococcus aureus, Escherichia coli and Clostridium perfringens were isolated and identified on different agars. Agar cup diffusion method was done to test the antimicrobial susceptibility of the neem leaves crude extract against those bacteria on Mueller-Hinton agar. Susceptibility was determined based on the zone of inhibition formed on the agar of each bacterium culture. Result: Neem was effective against Staphylococcus aureus and Clostridium perfringens. It was not effective against Escherichia coli. Conclusion: Neem extract has some promisable antimicrobial effects against Staphylococcus aureus and Clostridium perfringens causative bacterial infections

ANTIBACTERIAL EFFECTIVENESS OF PROSOPIS JULIFLORA AGAINST AEROBIC AND ANAEROBIC BACTERIA

Objective: The aim of this study is to analyse the antibacterial effectiveness of the leaf extract of Prosopis juliflora against aerobic and anaerobic bacteria and the objectives include maintaining the culture of Clostridium perfringens ATCC 3624, Staphylococcus aureus ATCC 25923, E. coli ATCC 25922 and to obtain an extract from the leaves of Prosopis juliflora by water extraction method. Agar cup diffusion testing is carried out to test the effectiveness of the extracted herb against the isolated strains of the above-mentioned bacteria. Methods: Cross-sectional study was conducted for 6 mo in the Clinical Microbiology Laboratory at SMCH. Extract from the leaves of Prosopis juliflora was collected by a water extraction method. Isolation of Clostridium perfringens (from RCMB), Staphylococcus aureus and Escherichia coli were done, following which the agar cup diffusion method was performed in which the collected extracts were placed as discs in the agar plate which had been inoculated with the strains of the isolated bacteria. The agar plate was then incubated anaerobically. Agar cup diffusion method is considered as a primary method to determine the antimicrobial effectiveness of the bacteria. Results: The leaf extract of Prosopis juliflora was found to be effective against both aerobic and anaerobic bacterial strains. Conclusion: Based on the work, the effectiveness of Prosopis juliflora was determined and the mechanism of susceptibility was identified. With future research works in the field, many such natural herbal extracts can be proven to be effective against many pathogenic microorganisms

ANTI-MICROBIAL EFFECTIVENESS OF LEMON GRASS OIL (CYMBOPOGAN CITRATE) AGAINST AEROBIC AND ANAEROBIC ORGANISMS

Objective: To find the antibacterial effectiveness of lemon grass (Cymbopogan citrate) oil against aerobic and anaerobic bacteria. Methods:This is an observational study conducted at Microbiology Clinical laboratory, Department of Microbiology, Saveetha Medical College and Hospital, Chennai. It was done over a period of 3 mo from January to March. The extracts of lemongrass leaves were investigated for its effectiveness against Staphylococcus aureus(S.aureus), Escherichia coli(E.coli) and Clostridium perfringens(C.perfringens) by Disc Diffusion assay. Results:Our study indicates that the extract of lemongrass oil shows antibacterial activity. Among the tested organisms, aerobic organisms were sensitive. Conclusion: This study thus provides insightful knowledge on antibacterial activity that would lead to further development of lemongrass oil for infectious diseases in the future

Comment letters to the National Commission on Commission on Fraudulent Financial Reporting, 1987 (Treadway Commission) Vol. 2

https://egrove.olemiss.edu/aicpa_sop/1662/thumbnail.jp

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

Analysis of gene and protein expression in FACS sorted bladder cells.

<p>(A) qPCR analysis of Sca-1 and CD34 mRNA expression levels in lin^- cells that were FACS sorted based on expression of Sca-1 and CD34. Expression level is normalized to Sca-1^-/CD34^-/lin^- Sca-1 expression levels. (B) qPCR analysis of smooth muscle myosin (SMM) and smooth muscle alpha <b>α</b> actin (ACTA2) of lin^- cells that were FACS sorted based on Sca-1 and CD34 expression levels. Expression level is normalized to Sca-1⁺/CD34⁺/lin^- SMM expression levels. (A, B) Asterisks represent significance values of P < 0.05 * and P < 0.01 ** after 1 Way ANOVA. Graphs represent expression averages from 4 separate sorts with 3–4 CD1 mice pooled per sort. (C, D) Confocal micrographs of Sca-1⁺/CD34⁺/lin^- sorted cells cultured on a glass coverslips after incubation with EdU for the first 24h (D) Two cells that are Sca-1⁺ (green), EdU⁺ (white) but SMM^- (red) at 48h in culture in α-MEM media. (E) Two cells that are Sca-1⁺ (green), EdU⁺ (white) and SMM⁺ (red) at 4d in culture in α-MEM media.</p

The Murine Bladder Supports a Population of Stromal Sca-1⁺/CD34⁺/lin^- Mesenchymal Stem Cells

<div><p>Bladder fibrosis is an undesired end point of injury of obstruction and often renders the smooth muscle layer noncompliant. In many cases, the long-term effect of bladder fibrosis is renal failure. Despite our understanding of the progression of this disease, little is known about the cellular mechanisms that lead to a remodeled bladder wall. Resident stem (progenitor) cells have been identified in various organs such as the brain, heart and lung. These cells function normally during organ homeostasis, but become dysregulated after organ injury. Here, we aimed to characterize a mesenchymal progenitor cell population as a first step in understanding its role in bladder fibrosis. Using fluorescence activated cell sorting (FACS), we identified a Sca-1⁺/ CD34⁺/ lin^- (PECAM^-: CD45^-: Ter119^-) population in the adult murine bladder. These cells were localized to the stromal layer of the adult bladder and appeared by postnatal day 1. Cultured Sca-1⁺/ CD34⁺/ lin^- bladder cells self-renewed, formed colonies and spontaneously differentiated into cells expressing smooth muscle genes. These cells differentiated into other mesenchymal lineages (chondrocytes, adipocytes and osteocytes) upon culture in induction medium. Both acute and partial obstruction of the bladder reduced expression of CD34 and changed localization of Sca-1 to the urothelium. Partial obstruction resulted in upregulation of fibrosis genes within the Sca-1⁺/CD34⁺/lin^- population. Our data indicate a resident, mesenchymal stem cell population in the bladder that is altered by bladder obstruction. These findings provide new information about the cellular changes in the bladder that may be associated with bladder fibrosis.</p></div

A subpopulation of Sca-1+/CD34+/lin- cells responds to sonic hedgehog (Shh) signaling.

<p>(A) Fluorescent confocal image of CD1 adult bladder stained with Sca-1 (green) in the stroma and Shh (red) in the urothelium. (B) <i>Gli-1</i>^{<i>CreERT2/+</i>}<i>; Rosa</i>^<i>mTmG+</i> EGFP⁺ cells (green) shown in the bladder stroma partially overlap with Sca-1⁺ cells (red). (C) EGFP⁺ cells (green) in the bladder stroma partially overlap with CD34⁺ cells (red). (D) EGFP⁺ cells (green) in the smooth muscle layer (red) are localized to a region of the detrusor layer near the stromal layer. (arrowheads). (E) 10% of Sca-1⁺/CD34⁺/lin^- cells from <i>Gli-1</i>^{<i>CreERT2/+</i>}<i>; Rosa</i>^<i>mTmG+</i> mouse bladders gated for SSC-A and FITC-A Gli1^egfp express EGFP. FACS analysis is from two separate sorts each containing bladder digests from two <i>Gli-1</i>^{<i>CreERT2/+</i>}<i>; Rosa</i>^<i>mTmG+</i> mice.</p