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1.
J Infect Dis ; 226(8): 1418-1427, 2022 10 17.
Article in English | MEDLINE | ID: mdl-36017801

ABSTRACT

This study was one of the first to detect Omicron sublineages BA.4 and BA.5 in wastewater from South Africa. Spearman rank correlation analysis confirmed a strong positive correlation between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral RNA in wastewater samples and clinical cases (r = 0.7749, P < .0001). SARS-CoV-2 viral load detected in wastewater, resulting from the Delta-driven third wave, was significantly higher than during the Omicron-driven fourth wave. Whole-genome sequencing confirmed presence of Omicron lineage defining mutations in wastewater with the first occurrence reported 23 November 2021 (BA.1 predominant). The variant spread rapidly, with prevalence of Omicron-positive wastewater samples rising to >80% by 10 January 2022 with BA.2 as the predominant sublineage by 10 March 2022, whilst on 18 April 2022 BA.4 and BA.5 were detected in selected wastewater sites. These findings demonstrate the value of wastewater-based epidemiology to monitor the spatiotemporal spread and potential origin of new Omicron sublineages.


Subject(s)
COVID-19 , SARS-CoV-2 , COVID-19/epidemiology , Humans , Prevalence , RNA, Viral/genetics , SARS-CoV-2/genetics , South Africa/epidemiology , Wastewater
2.
Molecules ; 26(7)2021 Mar 27.
Article in English | MEDLINE | ID: mdl-33801575

ABSTRACT

Momordica balsamina leaf extracts originating from three different geographical locations were analyzed using reversed-phase liquid chromatography (RP-LC) coupled to travelling wave ion mobility (TWIMS) and high-resolution mass spectrometry (HRMS) in conjunction with chemometric analysis to differentiate between potential chemotypes. Furthermore, the cytotoxicity of the three individual chemotypes was evaluated using HT-29 colon cancer cells. A total of 11 molecular species including three flavonol glycosides, five cucurbitane-type triterpenoid aglycones and three glycosidic cucurbitane-type triterpenoids were identified. The cucurbitane-type triterpenoid aglycones were detected in the positive ionization mode following dehydration [M + H - H2O]+ of the parent compound, whereas the cucurbitane-type triterpenoid glycosides were primarily identified following adduct formation with ammonia [M + NH4]+. The principle component analysis (PCA) loadings plot and a variable influence on projection (VIP) analysis revealed that the isomeric pair balsaminol E and/or karavilagen E was the key molecular species contributing to the distinction between geographical samples. Ultimately, based on statistical analysis, it is hypothesized that balsaminol E and/or karavilagen E are likely responsible for the cytotoxic effects in HT-29 cells.


Subject(s)
Antineoplastic Agents, Phytogenic/chemistry , Flavonols/chemistry , Glycosides/chemistry , Momordica/chemistry , Triterpenes/chemistry , Antineoplastic Agents, Phytogenic/isolation & purification , Antineoplastic Agents, Phytogenic/pharmacology , Cell Survival/drug effects , Chromatography, Reverse-Phase , Flavonols/isolation & purification , Flavonols/pharmacology , Glycosides/isolation & purification , Glycosides/pharmacology , HT29 Cells , Humans , Inhibitory Concentration 50 , Mass Spectrometry/methods , Plant Extracts/chemistry , Plant Leaves/chemistry , Principal Component Analysis , Structure-Activity Relationship , Triterpenes/isolation & purification , Triterpenes/pharmacology
3.
Integr Cancer Ther ; 20: 1534735420977684, 2021.
Article in English | MEDLINE | ID: mdl-33565349

ABSTRACT

In this study, the potential of an n-butanol fraction from Ricinus communis to prevent metastasis in MCF-7 breast cancer cells was investigated. The effect of the fraction on BUD-8 and MCF-7 cell viability was assessed using the MTT assay. Apoptotic cell death was analyzed by Hoechst staining assay. The antimetastatic effect of the fraction on MCF-7 cell was evaluated using the wound healing, adhesion and Boyden chamber invasion assays. Gelatin-zymography was used to assess the effect of the fraction on MMP-2 and MMP-9 activity. The expression profile of proteins implicated in metastasis and angiogenesis was determined using the human angiogenesis antibody array kit, following treatment with the fraction. BUD-8 cell viability was significantly reduced at concentrations between 300 and 500 µg/ml of the extract. In contrast, a significant reduction in cell viability was seen in MCF-7 cells treated with 400 to 500 µg/ml of the fraction. At sub-lethal concentrations (100 and 200 µg/ml) of the fraction, no nuclei morphological changes associated with apoptotic cell death were observed in MCF-7 cells. In addition, the fraction showed to have an inhibitory effect on MCF-7 cell migration, adhesion, invasiveness, and MMP-2 activity. Moreover, the fraction was seen to modulate the expression of several proteins, such as MMP-9, uPA, VEGF, and TGF-ß1, playing a role in the metastasis process. This study demonstrates that the n-butanol fraction of R. communis can inhibit major steps of the metastatic cascade and modulate metastasis regulatory proteins. Thus, the fraction can be considered a potential source of antimetastatic agents that could be useful in the treatment of malignant cancers.


Subject(s)
Breast Neoplasms , 1-Butanol , Breast Neoplasms/drug therapy , Breast Neoplasms/genetics , Butanols/pharmacology , Cell Adhesion , Cell Line, Tumor , Cell Movement , Female , Gene Expression Regulation, Neoplastic , Humans , MCF-7 Cells , Neoplasm Invasiveness , Ricinus
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