First report of sweepoviruses infecting Ipomeas batatas L. cultivars and landraces in Trinidad.

Root crops, referred to as ground provisions in the Caribbean, are traditional staples in Trinidad. One widely consumed example is sweet potato (Ipomeas batatas L.). The crop is mainly produced by subsistence farming which together with imports from neighboring Caribbean countries meet domestic demand (Singh et al. 2008). The Central Experiment Station, situated in the eastern part of Trinidad, maintains a sweet potato germplasm collection comprising both imported and locally-sourced landraces for cultivar development and distribution of propagules. In May 2017 chlorosis and leaf curling symptoms, typically associated with sweepoviruses, were observed on imported cultivars, Centennial, Jewel, 86 BM 31, TIB 313, TIB 8 21 1, and S128, and the landraces, Kick Up Jenny, John, and Carrot. Leaf samples from these nine symptomatic plants were collected for analysis, along with samples from the asymptomatic landrace, Chickenfoot. Total nucleic acids were extracted (Sharma et al. 2008) and the samples were assayed by PCR using degenerate primers SPG1 and SPG2 (Li et al. 2004) that target the replication associated protein gene (ORF C1), a highly conserved region of sweepoviruses. Amplicons of 912-bp were obtained from two of the nine symptomatic plants (TIB 8 21 1, Kick Up Jenny), but not from the asymptomatic Chickenfoot. The same samples were assayed by PCR amplification using primers SpvF and SpvR (Avelar 2015) which are specific to a highly conserved 632-bp region of the coat protein gene (ORF V1) of sweet potato leaf curl virus (SPLCV). All 10 samples tested positive for SPLCV, including the asymptomatic landrace, Chickenfoot. The ORF V1 PCR products from three of the 10 samples, namely Chickenfoot, TIB 8 21 1, and Kick Up Jenny, were cloned and sequenced (two clones per sample). Comparison of the sequences (GenBank accession nos. OR882007 [Chickenfoot], OR913125 [TIB 8 21 1] and OR913126 [Kick Up Jenny]) identified up to 4% nt sequence variability between samples. In BLASTn analysis, they were most closely related to the SPLCV isolate China:Sichuan (GenBank accession no. KJ013557), sharing 94 to 98% nt identity. Total nucleic extracts from one representative sample (TIB 8 21 1) was used as template for rolling circle amplification (RCA, TempliPhi Amplification Kit, GE Healthcare Life Sciences, Piscataway, NJ, USA). Digestion of the RCA product with StuI (Thermo Scientific, MA, USA) yielded ~2.8 kb DNA fragments indicative of monomeric full length genomes. Digested fragments were cloned, completely sequenced and deposited in GenBank under the accession nos. OR866202 (2,821 nts) and OR866203 (2,828 nts). Two species of sweepoviruses were detected. In BLASTn analysis, OR866202 showed 95% nt identity with sweet potato golden vein associated virus (SPGVaV) US:MS:1B-3 (GenBank accession no. HQ333143.1) which is a recombinant virus comprised of SPLCV and sweet potato leaf curl Georgia virus (SPLCGV) (Zhang and Ling 2011) and in BLASTx analysis OR866202 was most similar (92-99%) to SPLCV isolates from Brazil (GenBank accession nos. ACI23475.1, AGW16179.1, ACY79479.1), Peru (GenBank accession no. ACY79466.1) and China (GenBank accession nos. ACY79439.1). OR866203 shared 96% nt identity with SPLCV China:Henan25(8):2012 (GenBank accession no. KF040465.1) in BLASTn analysis and BLASTx analysis revealed ≥ 94% aa sequence identity with SPLCV from Brazil (GenBank accession nos. ACI23475.1, AGW16179.1, ADZ96559.1), Peru (GenBank accession no. ACY79479.1), China (GenBank accession no. ACY79466.1). and Spain (GenBank accession no. QWQ56365.1). Both Trinidad isolates also showed 90-96% nt identity with SPLCV from Korea (GenBank accession no.s KT992061.1, KT992064.1, unpublished). This is the first detection of sweepoviruses in Trinidad. SPGVaV has been reported in Brazil, the United States and Korea (Kil et al. 2014), while SPLCV has been described in other Caribbean islands, including Cuba, Jamaica, Puerto Rico, St. Vincent (Cuellar et al. 2015), and Barbados (Alleyne et al. 2019), as well as several countries in South America. Although Koch's postulates were not completed, our findings suggest that sweet potato crops in Trinidad harbor sweepoviruses, notwithstanding efforts to distribute pathogen-free materials and, in some instances, the apparent absence of visible symptoms on infected plants. Further studies on the management and impact of these viruses are necessary, including their prevalence in the sweet potato production regions of Trinidad.

Mitochondria and cytochrome components released into the plasma of severe COVID-19 and ICU acute respiratory distress syndrome patients.

INTRODUCTION: Proteomic analysis of human plasma by LC-ESI-MS/MS has discovered a limited number of new cellular protein biomarkers that may be confirmed by independent biochemical methods. Analysis of COVID-19 plasma has indicated the re-purposing of known biomarkers that might be used as prognostic markers of COVID-19 infection. However, multiple molecular approaches have previously indicated that the SARS-COV2 infection cycle is linked to the biology of mitochondria and that the response to infections may involve the action of heme containing oxidative enzymes. METHODS: Human plasma from COVID-19 and ICU-ARDS was analyzed by classical analytical biochemistry techniques and classical frequency-based statistical approaches to look for prognostic markers of severe COVID-19 lung damage. Plasma proteins from COVID-19 and ICU-ARDS were identified and enumerated versus the controls of normal human plasma (NHP) by LC-ESI-MS/MS. The observation frequency of proteins detected in COVID-19 and ICU-ARDS patients were compared to normal human plasma, alongside random and noise MS/MS spectra controls, using the Chi Square (χ2) distribution. RESULTS: PCR showed the presence of MT-ND1 DNA in the plasma of COVID-19, ICU-ARDS, as well as normal human plasma. Mitochondrial proteins such as MRPL, L2HGDH, ATP, CYB, CYTB, CYP, NDUF and others, were increased in COVID-19 and ICU-ARDS plasma. The apparent activity of the cytochrome components were tested alongside NHP by dot blotting on PVDF against a purified cytochrome c standard preparation for H2O2 dependent reaction with luminol as measured by enhanced chemiluminescence (ECL) that showed increased activity in COVID-19 and ICU-ARDS patients. DISCUSSION: The results from PCR, LC-ESI-MS/MS of tryptic peptides, and cytochrome ECL assays confirmed that mitochondrial components were present in the plasma, in agreement with the established central role of the mitochondria in SARS-COV-2 biology. The cytochrome activity assay showed that there was the equivalent of at least nanogram amounts of cytochrome(s) in the plasma sample that should be clearly detectable by LC-ESI-MS/MS. The release of the luminol oxidase activity from cells into plasma forms the basis of a simple and rapid test for the severity of cell damage and lung injury in COVID-19 infection and ICU-ARDS.

Recent, national trends in US adolescent use of menthol and non-menthol cigarettes.

OBJECTIVE: In light of the current U.S. Food and Drug Administration (FDA) proposal to ban menthol cigarettes, this study updates trends in menthol cigarette use among adolescents age 13-18 years up to the year 2020. The study considers a potential role for the ban to reduce black/non-black disparities in menthol cigarette use, as well as a counterargument that a ban is not necessary because menthol use is already diminishing. METHODS: Data are from annual, cross-sectional, nationally representative Monitoring the Future (MTF) surveys of 85 547 8th, 10th and 12th grade students surveyed between 2012 and 2020. Analyses include trends in past 30-day menthol and non-menthol cigarette smoking among the total adolescent population, as well as stratified by race/ethnicity. RESULTS: Declines in adolescent menthol and non-menthol cigarette smoking continued through 2020 so that in 2018-2020 past 30-day prevalence for each was less than 1% for non-Hispanic black adolescents and less than 2.2% for non-black adolescents. For non-Hispanic black adolescents no smoking declines in mentholated or non-mentholated cigarette use from 2015-2017 to 2018-2020 were statistically significant, in part because prevalence levels approached a floor effect and had little room to fall further. Menthol levels were lower for non-Hispanic black versus all other adolescents in all study years. CONCLUSIONS: Continuing declines in adolescent menthol prevalence indicate that both menthol prevalence and also black/non-black disparities in its use are steadily decreasing. However, these decreases in adolescence will take decades to reach later ages through generational replacement. Efforts to accelerate menthol decreases will require new initiatives to increase cessation among adult menthol users.

Viral Threats to Fruit and Vegetable Crops in the Caribbean.

Viruses pose major global challenges to crop production as infections reduce the yield and quality of harvested products, hinder germplasm exchange, increase financial inputs, and threaten food security. Small island or archipelago habitat conditions such as those in the Caribbean are particularly susceptible as the region is characterized by high rainfall and uniform, warm temperatures throughout the year. Moreover, Caribbean islands are continuously exposed to disease risks because of their location at the intersection of transcontinental trade between North and South America and their role as central hubs for regional and global agricultural commodity trade. This review provides a summary of virus disease epidemics that originated in the Caribbean and those that were introduced and spread throughout the islands. Epidemic-associated factors that impact disease development are also discussed. Understanding virus disease epidemiology, adoption of new diagnostic technologies, implementation of biosafety protocols, and widespread acceptance of biotechnology solutions to counter the effects of cultivar susceptibility remain important challenges to the region. Effective integrated disease management requires a comprehensive approach that should include upgraded phytosanitary measures and continuous surveillance with rapid and appropriate responses.

Translational research: putting the right price on innovation.

The animal health sector makes a substantial contribution to innovation in the field of human health, but this is undervalued, says Lloyd Reeve-Johnson. He argues that this contribution needs to be recognised and quantified if the benefits of One Health, and the potential of the veterinary profession, are to be realised.