Brayrichmond1043

Tobacco mosaic virus (TMV) has served as a model organism for pathbreaking work in plant pathology, virology, biochemistry and applied genetics for more than a century. We were intrigued by a photograph published in Phytopathology in 1934 showing that Tabasco pepper plants responded to TMV infection with localized necrotic lesions, followed by abscission of the inoculated leaves. This dramatic outcome of a biological response to infection observed by Francis O. Holmes, a virologist at the Rockefeller Institute for Medical Research, was used to score plants for resistance to TMV infection. learn more Our objective was to gain a better understanding of early to mid-twentieth century ideas of genetic resistance to viruses in crop plants. We investigated Holmes' observation as a practical exercise in reworking an experiment, having been inspired by Pamela Smith's innovative Making and Knowing Project. We had a great deal of difficulty replicating Holmes' experiment, finding that biological materials and experimental customs change over time, in ways that ideas do not. Using complementary tools plus careful study and interpretation of the original text and figures, we were able to rework, yet only partially replicate, this experiment. Reading peer-reviewed manuscripts that cited Holmes' 1934 report provided an additional level of insight into the interpretation and replication of this work in the decades that followed. From this, we touch on how experimental reworking can inform our strategies to address the reproducibility "crisis" in twenty-first century science.In this study, we investigated antibiotic-resistant microorganisms isolated by the direct plating method from 6 playgrounds in the city of Pushchino, Moscow Region, with different types of coating sand, soil with sand, grass and a modern playground coating made of pressed rubber crumb. According to the results of the study, sand is the cleanest type of coating, both in terms of the total count of cultivated microorganisms (8 × 105/g of substrate) and in terms of the content of resistant strains. The most contaminated both in terms of the total count of cultivated microorganisms (1.2-1.9 × 109/g of substrate) and in terms of the content of antibiotic-resistant strains was the coating of pressed rubber crumb. We isolated 65 antibiotic-resistant strains of fluorescent pseudomonads. Nine Pseudomonas strains were found to contain antibiotic resistance plasmids (one belongs to P-1 incompatibility group, seven to IncP-7 and one to unidentified incompatibility group). For the first time, we discovered a conjugative plasmid pD4A-46 conferring tetracycline resistance and belonging to the P-7 incompatibility group. Taking into account the results obtained under this study, it can be recommended to periodically treat the crumb rubber coating with non-toxic antiseptics, i.e. hydrogen peroxide or chlorhexidine.

The defense response of potato tubers afflicted with zebra chip disease involves oxidatively mediated upregulation of nucleases that likely modulate localized programmed cell death to restrict the phloem-mobile, CLso bacterial pathogen to the vasculature. Zebra chip (ZC) is a bacterial disease of potato (Solanum tuberosum L.) caused by Candidatus Liberibacter solanacearum (CLso). Tubers from infected plants develop characteristic brown discoloration of the vasculature, a result of localized programmed cell death (PCD). We examined the potential contribution of nucleases in the response of tubers to CLso infection. Specific activities of the major isozymes of dsDNase, ssDNase, and RNase were substantially upregulated in tubers from CLso-infected plants, despite their significantly lower soluble protein content. However, ZC disease had no effect on nuclease isozyme profiles. Activities of the predominant nuclease isoforms from healthy and CLso-infected tubers had similar pH optima, thermotolerance, and respon. By contrast, ZnSO4 inhibited the activities of RNases. DTT and CuSO4 inhibited the activities of all three nucleases. These results suggest that activation of tuber nucleases is dependent on the oxidation of sulfhydryl groups to disulfide and/or oxidation of Zn to Zn+2. In light of previous published results that established extensive CLso-induced upregulation of oxidative stress metabolism in tubers, we propose a model to show how increased nuclease activity could result from a glutathione-mediated oxidation of nuclease sulfhydryl groups in diseased tubers. DNases and RNases are likely an integral part of the hypersensitive response and may modulate PCD to isolate the pathogen to the vascular tissues of tubers.Asian Americans are more likely to be unaware that they have hypertension compared to non-Hispanic white Americans, despite having higher risk of hypertension at lower body-mass indices. Furthermore, immigrants are more likely than their United States (U.S.)-born counterparts to have undiagnosed hypertension, placing them at greater risk of subsequent morbidity and mortality. This study examines the social determinants of undiagnosed hypertension among Asian American immigrants. Using a study of foreign-born Chinese and Korean Americans between the ages of 50-75 years-old recruited from physicians' clinics in the Baltimore-Washington DC Metropolitan Area (n = 355), we used blood pressure readings measured by trained staff members, self-reported diagnosis by a medical professional, and self-reported hypertension medication use to determine hypertension status-whether patients were non-hypertensive, had diagnosed hypertension, or had undiagnosed hypertension. Using multinomial logistic regression, we examined how demographic, socioeconomic, and immigration-related factors were associated with hypertension status. Results indicated that older age, male gender, Korean subgroup, and marital status were associated with having diagnosed hypertension compared to being non-hypertensive. Lack of health insurance was the strongest predictor of having undiagnosed hypertension compared to being non-hypertensive. Acculturation variables had no strong associations with hypertension status. We then explored correlates of health insurance status for Chinese and Korean American immigrants. Those without health insurance were more likely to have lower income and to be not currently employed. Our findings point to the importance of increasing health insurance access for Asian American immigrant groups to ensure that hypertension is not left undiagnosed and untreated.Post-mortem examination plays a pivotal role in understanding the pathobiology of the SARS-CoV-2; thus, the optimization of virus detection on the post-mortem formalin-fixed paraffin-embedded (FFPE) tissue is needed. Different techniques are available for the identification of the SARS-CoV-2, including reverse transcription polymerase chain reaction (RT-PCR), immunohistochemistry (IHC), in situ hybridization (ISH), and electron microscopy. The main goal of this study is to compare ISH versus RT-PCR to detect SARS-CoV-2 on post-mortem lung samples of positive deceased subjects. A total of 27 samples were analyzed by RT-PCR targeting different viral RNA sequences of SARS-CoV-2, including envelope (E), nucleocapsid (N), spike (S), and open reading frame (ORF1ab) genes and ISH targeting S and Orf1ab. All 27 cases showed the N gene amplification, 22 out of 27 the E gene amplification, 26 out of 27 the S gene amplification, and only 6 the ORF1ab gene amplification. The S ISH was positive only in 12 out of 26 cases positive by RT-PCR. The S ISH positive cases with strong and diffuse staining showed a correlation with low values of the number of the amplification cycles by S RT-PCR suggesting that ISH is a sensitive assay mainly in cases carrying high levels of S RNA. In conclusion, our findings demonstrated that ISH assay has lower sensitivity to detect SARS-CoV-2 in FFPE compared to RT-PCR; however, it is able to localize the virus in the cellular context since it preserves the morphology.

The aim of this study was to determine the effectiveness of educational interventions aimed at agricultural workers' knowledge, behaviour, and risk perception for reducing the risk of pesticide exposure.

All studies published in the English language between the years 2000 and 2020 were screened on relevant databases. The study protocol was registered on PROSPERO. Randomised controlled studies (RCTs) and quasi-experimental studies meeting the inclusion and exclusion criteria according to the PICOS criteria were included. In line with the PRISMA flow diagram, 38 studies were included in the systematic review and meta-analysis. Risk of bias was assessed with the Cochrane risk-of-bias assessment tool. A random-effects model was applied and Hedge's g was used to calculate effect size.

Five of the included studies are RCTs, two are cluster RCTs, 17 are quasi-experimental studies with experimental and control groups, and 14 have single-group pretest-posttest study designs. Educational interventions had a largeponents, and evidence-based practices.

To investigate Tau pathology using multimodal biomarkers of neurodegeneration and neurocognition in participants with myotonic dystrophy type 1 (DM1).

We recruited twelve participants with DM1 and, for comparison, two participants with Alzheimer's Disease (AD). Participants underwent cognitive screening and social cognition testing using the Dépistage Cognitif de Québec (DCQ), among other tests. Biomarkers included Tau PET with [18F]-AV-1451, CSF (Aβ, Tau, phospho-Tau), and plasma (Aβ, Tau, Nf-L, GFAP) studies.

Of the twelve DM1 participants, seven completed the full protocol (Neurocognition 11/12; PET 7/12, CSF 9/12, plasma 12/12). Three DM1 participants were cognitively impaired (CI). On average, CI DM1 participants had lower scores on the DCQ compared to cognitively unimpaired (CU) DM1 participants (75.5/100 vs. 91.4/100) and were older (54 vs. 44years old) but did not differ in years of education (11.3 vs. 11.1). The majority (6/7) of DM1 participants had no appreciable PET signal. Only one of the Csma Nf-L and GFAP levels, suggestive of other, possibly related, central brain alterations which motivate further research. This pioneering study provides novel insights towards the potential relationship between biomarkers and neurocognitive deficits commonly seen in DM1.

We observed heterogenous cognitive and biomarker profiles in individuals with DM1. While some participants presented with abnormal PET and/or CSF Tau, these patterns were highly variable and only present in a small subset. Although DM1 may indeed represent a non-AD Tauopathy, the Tau-PET tracer used in this study was unable to detect an in vivo Tau DM1 signature in this small cohort. Interestingly, most DM1 participants presented with elevated plasma Nf-L and GFAP levels, suggestive of other, possibly related, central brain alterations which motivate further research. This pioneering study provides novel insights towards the potential relationship between biomarkers and neurocognitive deficits commonly seen in DM1.Both Gram-positive and Gram-negative bacteria release nano-sized lipid bilayered particles, known as membrane vesicles (MVs), into external environments. Although MVs play a variety of roles in bacterial physiology and pathogenesis, the mechanisms underlying MV formation in Gram-positive microorganisms such as Staphylococcus aureus remain obscure. Bacterial MV production can be induced in response to stress conditions, and the alternative sigma factor B (SigB) functions as a central regulator of the stress response in Gram-positive bacteria. In a previous study, we demonstrated that the SigB(Q225P) substitution mutation in S. aureus promotes biofilm formation. Here, we report that the SigB(Q225P) mutation also increases MV production in this important pathogen. LacZ reporter assays and electrophoretic mobility shift assays showed that the Q225P substitution reduces SigB binding to the promoter region of the thermonuclease gene (nuc), resulting in a significant reduction in Nuc expression. Deletion of nuc markedly enhances S.