Methods and Protocols最新文献

{"title":"Mapping m6A Sites on HIV-1 RNA Using Oligonucleotide LC-MS/MS","authors":"Alice Baek, Asif Rayhan, Ga-Eun Lee, Sarah Golconda, H. Yu, Shihyoung Kim, P. Limbach, Balasubrahmanyam Addepalli, Sanggu Kim","doi":"10.3390/mps7010007","DOIUrl":"https://doi.org/10.3390/mps7010007","url":null,"abstract":"The biological significance of chemical modifications to the ribonucleic acid (RNA) of human immunodeficiency virus type-1 (HIV-1) has been recognized. However, our understanding of the site-specific and context-dependent roles of these chemical modifications remains limited, primarily due to the absence of nucleotide-resolution mapping of modification sites. In this study, we present a method for achieving nucleotide-resolution mapping of chemical modification sites on HIV-1 RNA using liquid chromatography and tandem mass spectrometry (LC–MS/MS). LC–MS/MS, a powerful tool capable of directly analyzing native RNAs, has proven effective for mapping RNA modifications in small RNA molecules, including ribosomal RNA and transfer RNA. However, longer RNAs have posed challenges, such as the 9 Kb HIV-1 virion RNA, due to the complexity of and ambiguity in mass differences among RNase T1-cleaved RNA fragments in LC-MS/MS data. Here, we introduce a new target RNA enrichment method to isolate small local RNA fragments of HIV-1 RNA that potentially harbor site-specific N6-methyladenosine (m6A) modifications. In our initial trial, we used target-specific DNA probes only and encountered insufficient RNA fragmentation due to inefficient S1 digestion near the target site. Recognizing that inefficient S1 digestion by HIV-1 RNA is likely due to the formation of secondary structures in proximity to the target site, we designed multiple DNA probes annealing to various sites of HIV-1 RNA to better control the structures of RNA substrates for S1 digestion. The use of these non-target DNA probes significantly improved the isolation of more homogeneous target RNA fragments of approximately 50 bases in length. Oligonucleotide LC-MS/MS analysis of these isolated target RNA fragments successfully separated and detected both m6A-methylated and non-methylated oligomers at the two m6A-predicted sites. The principle of this new target enrichment strategy holds promise and should be broadly applicable to the analysis of any lengthy RNA that was previously deemed infeasible for investigation using oligonucleotide LC-MS/MS.","PeriodicalId":18715,"journal":{"name":"Methods and Protocols","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139439522","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimal Selection of Sampling Points within Sewer Networks for Wastewater-Based Epidemiology Applications","authors":"Yao Yao, Yibo Zhu, Regina Nogueira, Frank Klawonn, Markus Wallner","doi":"10.3390/mps7010006","DOIUrl":"https://doi.org/10.3390/mps7010006","url":null,"abstract":"Wastewater-based epidemiology (WBE) has great potential to monitor community public health, especially during pandemics. However, it faces substantial hurdles in pathogen surveillance through WBE, encompassing data representativeness, spatiotemporal variability, population estimates, pathogen decay, and environmental factors. This paper aims to enhance the reliability of WBE data, especially for early outbreak detection and improved sampling strategies within sewer networks. The tool implemented in this paper combines a monitoring model and an optimization model to facilitate the optimal selection of sampling points within sewer networks. The monitoring model utilizes parameters such as feces density and average water consumption to define the detectability of the virus that needs to be monitored. This allows for standardization and simplicity in the process of moving from the analysis of wastewater samples to the identification of infection in the source area. The entropy-based model can select optimal sampling points in a sewer network to obtain the most specific information at a minimum cost. The practicality of our tool is validated using data from Hildesheim, Germany, employing SARS-CoV-2 as a pilot pathogen. It is important to note that the tool’s versatility empowers its extension to monitor other pathogens in the future.","PeriodicalId":18715,"journal":{"name":"Methods and Protocols","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139383979","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Introducing Artificial Intelligence in Interpretation of Foetal Cardiotocography: Medical Dataset Curation and Preliminary Coding—An Interdisciplinary Project","authors":"J. L. Aeberhard, A. Radan, Ramin Abolfazl Soltani, K. Strahm, S. Schneider, Adriana Carrié, Mathieu Lemay, Jens Krauss, Ricard Delgado-Gonzalo, Daniel Surbek","doi":"10.3390/mps7010005","DOIUrl":"https://doi.org/10.3390/mps7010005","url":null,"abstract":"Artificial intelligence (AI) is gaining increasing interest in the field of medicine because of its capacity to process big data and pattern recognition. Cardiotocography (CTG) is widely used for the assessment of foetal well-being and uterine contractions during pregnancy and labour. It is characterised by inter- and intraobserver variability in interpretation, which depends on the observers’ experience. Artificial intelligence (AI)-assisted interpretation could improve its quality and, thus, intrapartal care. Cardiotocography (CTG) raw signals from labouring women were extracted from the database at the University Hospital of Bern between 2006 and 2019. Later, they were matched with the corresponding foetal outcomes, namely arterial umbilical cord pH and 5-min APGAR score. Excluded were deliveries where data were incomplete, as well as multiple births. Clinical data were grouped regarding foetal pH and APGAR score at 5 min after delivery. Physiological foetal pH was defined as 7.15 and above, and a 5-min APGAR score was considered physiologic when reaching ≥7. With these groups, the algorithm was trained to predict foetal hypoxia. Raw data from 19,399 CTG recordings could be exported. This was accomplished by manually searching the patient’s identification numbers (PIDs) and extracting the corresponding raw data from each episode. For some patients, only one episode per pregnancy could be found, whereas for others, up to ten episodes were available. Initially, 3400 corresponding clinical outcomes were found for the 19,399 CTGs (17.52%). Due to the small size, this dataset was rejected, and a new search strategy was elaborated. After further matching and curation, 6141 (31.65%) paired data samples could be extracted (cardiotocography raw data and corresponding maternal and foetal outcomes). Of these, half will be used to train artificial intelligence (AI) algorithms, whereas the other half will be used for analysis of efficacy. Complete data could only be found for one-third of the available population. Yet, to our knowledge, this is the most exhaustive and second-largest cardiotocography database worldwide, which can be used for computer analysis and programming. A further enrichment of the database is planned.","PeriodicalId":18715,"journal":{"name":"Methods and Protocols","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139385685","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Scoping Review Protocol of Social Determinants of HIV/TB Coinfections in Sub-Saharan Africa","authors":"Lucas Banda, Olanrewaju Oladimeji","doi":"10.3390/mps7010004","DOIUrl":"https://doi.org/10.3390/mps7010004","url":null,"abstract":"Introduction: Tuberculosis (TB) and Human Immunodeficiency Virus (HIV) remain major public health issues in sub-Saharan Africa. The co-occurrence of these diseases is a growing concern in the region, and social determinants, the circumstances under which people are born, live, work, and age, are known to influence the risk of disease transmission, diagnosis, treatment, and outcomes. Here, we present a protocol for the evidence synthesis on the social determinants of HIV/TB coinfections in sub-Saharan Africa. The high prevalence of Tuberculosis (TB) and Human Immunodeficiency Virus (HIV) in sub-Saharan Africa presents significant public health challenges. TB/HIV comorbidity is influenced by various social determinants, including social, economic, cultural, and environmental factors, impacting disease transmission risk, accurate diagnosis, and treatment outcomes. This study protocol aims to provide an evidence synthesis on the social determinants of HIV/TB coinfection in sub-Saharan Africa. Methods and analysis: The researchers will use the Arksey and O’Malley’s (2005) methodological framework to guide the scoping review. First, databases such as PubMed, MEDLINE, Web of Science, and PsychInfo will be searched. The researchers will then proceed in two steps. Before finalising the study selection, two independent reviewers will examine the article titles and abstracts for eligibility and inclusion. The researchers will then conduct a full-text screening of the articles based on the selected titles and abstracts. The authors’ tool will be used to extract data, ensuring that the articles are properly screened and that the risk of bias is minimized. The chosen studies will be examined using a standardized tool to examine all bibliographic data and study characteristics. Ethics and dissemination: The review will provide an overview of the social determinants influencing the prevalence and outcomes of TB/HIV comorbidity in the region, as well as identify any research gaps. Policymakers, researchers, and healthcare professionals will benefit from the findings in developing targeted interventions to address the social determinants of TB/HIV comorbidity in sub-Saharan Africa.","PeriodicalId":18715,"journal":{"name":"Methods and Protocols","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139385505","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Generation of Viral Particles with Brain Cell-Specific Tropism by Pseudotyping HIV-1 with the Zika Virus E Protein","authors":"Hai Dang Ngo, Jan Patrick Formanski, Vivien Grunwald, Birco Schwalbe, Michael Schreiber","doi":"10.3390/mps7010003","DOIUrl":"https://doi.org/10.3390/mps7010003","url":null,"abstract":"Flaviviruses are a family of RNA viruses that includes many known pathogens, such as Zika virus (ZIKV), West Nile virus (WNV), dengue virus (DENV), and yellow fever virus (YFV). A pseudotype is an artificial virus particle created in vitro by incorporating the flavivirus envelope proteins into the structure of, for example, a retrovirus such as human immunodeficiency virus type-1 (HIV-1). They can be a useful tool in virology for understanding the biology of flaviviruses, evaluating immune responses, developing antiviral strategies but can also be used as vectors for gene transfer experiments. This protocol describes the generation of a ZIKV/HIV-1 pseudotype developed as a new tool for infecting cells derived from a highly malignant brain tumor: glioblastoma multiforme grade 4.","PeriodicalId":18715,"journal":{"name":"Methods and Protocols","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2023-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139150253","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nesting Ecology of <i>Lepidochelys olivacea</i> in Lobito, Angola.","authors":"Inês M Ferreira, Luz Murillo, Jean-Marie Le-Corre, Marco Correia, Rita Anastácio, Mário J Pereira","doi":"10.3390/mps7010002","DOIUrl":"10.3390/mps7010002","url":null,"abstract":"<p><p>The scarcity on the Atlantic coast of the African sea turtle population and its dynamics data is well known. This article discusses the nesting ecology methods and analysis of a nascent Angolan project aimed at preserving the nesting female population of the Olive Ridley turtle (<i>Lepidochelys olivacea</i>) on the coast of Lobito. This study examines the nesting ecology of this species from 2020 to 2023. Females had an average CCL of 70.2 cm and CCW of 68.5 cm. These females laid 127 eggs in nests that averaged 47.0 cm deep. The <i>ex situ</i> nest incubation period averaged 60 days, and the hatchling success was 82.1%. Some techniques used in this project require modifications and enhancements. The utilization of photo identification did not yield the anticipated outcomes, prompting the adoption of passive integrated transponders (PITs) in the last season. However, due to limited funding, the success of this method is contingent upon an augmented field effort, allowing for the recapture of a larger number of females. The continuity of this project hinges upon collaboration between higher authorities and the local community. Together, it is possible to deepen the understanding of the nesting ecology of this species and address pivotal issues for its conservation, thereby implementing the most effective preservation measures.</p>","PeriodicalId":18715,"journal":{"name":"Methods and Protocols","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2023-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10801490/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139512993","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Valorizing Tree-Nutshell Particles as Delivery Vehicles for a Natural Herbicide","authors":"Jong H. Kim, K. Chan, W. Hart-Cooper, DeAngela Ford, Kaydren Orcutt, Jeffrey D Palumbo, Christina C. Tam, William J. Orts","doi":"10.3390/mps7010001","DOIUrl":"https://doi.org/10.3390/mps7010001","url":null,"abstract":"The United States is a principal producer of tree nuts (almonds, pistachios, and walnuts), resulting in the generation of excess of tree-nutshell by-products each year, with few market outlets. A nutshell is an essential, lignocellulosic layer that protects a kernel (seed) from the environment during cultivation. The objective of this study was to develop nutshell by-products as herbicide delivery systems, which would not only enable sustainable weed control in fields but also increases nutshell value and reduce the cost of waste disposal. We recently identified a natural salicylaldehyde (SA) that emits volatiles with both herbicidal and antifungal properties. In this study, walnut shell particles saturated with 0.8 to 1.6 M SA were developed as delivery vehicles for SA to soil, which allowed for the controlled release of an SA fumigant for weed control. The pre- and post-emergent herbicidal efficacy of SA was investigated using model monocot (Lolium arundinaceum (Schreb.) Darbysh; turfgrass) and dicot (Brassica rapa var. pekinensis; Chinese cabbage) plants. We compared (1) the effects of different types of solvents for dissolving SA (dimethyl sulfoxide (DMSO) and ethanol (60%, v/v)), and (2) the effect of covering soil with plastic layers (i.e., soil pasteurization) or not covering soil during SA fumigation using nutshells. Results: In the pre-emergent herbicidal testing with the soil covered, the dicot plants exhibited levels of higher susceptibility to SA in DMSO emitted from nutshells when compared to the monocot plants. The seed germination frequencies in the dicots were 15% and 1% with 0.8 and 1.6 M SA, respectively, while those in the monocots were 32% and 18%, respectively, under the same test conditions. In the post-emergent herbicidal testing with the soil covered, the growth of both the monocot and dicot plants was completely prevented after 5 to 7 days of SA fumigation, resulting in the deaths of entire plants. It was noteworthy that in the post-emergent herbicidal testing, SA dissolved in ethanol (60%, v/v) completely disrupted the growth of the monocot and dicot plants as early as 3 days after SA emission from the nutshells, even without the soil being covered. Tree-nutshell particles could serve as effective SA delivery vehicles with controlled release capabilities for SA. The SA exhibited pre- and post-emergent herbicidal activities against the monocot and dicot plants at most growth stages. SA (0.8 and 1.6 M) dissolved in ethanol (60%, v/v) might exert a synergism for higher herbicidal activity after emission from nutshells. Since tree nuts capture/store a substantial amount of carbon over their life-cycles, the new and sustainable utility of using nutshells not only reduces carbon emissions but also valorizes tree-nut by-products, thus benefitting the tree-nut industry.","PeriodicalId":18715,"journal":{"name":"Methods and Protocols","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2023-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139170554","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of a 3D Perfused In Vitro System to Assess Proangiogenic Properties of Compounds.","authors":"Johanna Alm, Benoit Fischer, Alexandra Emanuela Burger, Francesca Moretti","doi":"10.3390/mps6060119","DOIUrl":"10.3390/mps6060119","url":null,"abstract":"<p><p>Perturbation of angiogenesis is associated with a variety of diseases and pro- as well as antiangiogenic therapies are being actively explored. Additionally, unintended adverse drug effects on angiogenesis might lead to promotion of tumor progression and cardiovascular complications. Several tri-dimensional microfluidic vessel-on-chip systems have been described that allow a more accurate investigation of vascular physiology and pathology, compared to the two-dimensional static culture of endothelial cells. The OrganoPlate^® angiogenesis-on-chip system has been demonstrated to be amenable to high-throughput screening for the antiangiogenic properties of molecules. We set out to adapt this system for high-throughput screening of molecules with proangiogenic properties. Our technical advancement of the OrganoPlate^® angiogenesis-on-chip assay expands its applicability in the early screening of both anti- as well as proangiogenic properties of compounds for therapeutic modulation of angiogenesis as well as the identification of angiogenesis-associated drug-induced vascular toxicities.</p>","PeriodicalId":18715,"journal":{"name":"Methods and Protocols","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2023-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10745376/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138830498","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Magnetic Resonance Imaging as a Tool for Monitoring Intratibial Growth of Experimental Prostate Cancer Metastases in Mice","authors":"Junchi Huang, Mikael Montelius, Jan-Erik Damber, K. Welén","doi":"10.3390/mps6060118","DOIUrl":"https://doi.org/10.3390/mps6060118","url":null,"abstract":"Bone metastases cause morbidity and mortality in several human cancer forms. Experimental models are used to unravel the mechanisms and identify possible treatment targets. The location inside the skeleton complicates accurate assessment. This study evaluates the performance of magnetic resonance imaging (MRI) of prostate cancer tumors growing intratibially in mice. MRI detected intratibial tumor lesions with a sensitivity and specificity of 100% and 89%, respectively, compared to histological evaluation. Location and some phenotypical features could also be readily detected with MRI. Regarding volume estimation, the correlation between MRI and histological assessment was high (p < 0.001, r = 0.936). In conclusion, this study finds MRI to be a reliable tool for in vivo, non-invasive, non-ionizing, real-time monitoring of intratibial tumor growth.","PeriodicalId":18715,"journal":{"name":"Methods and Protocols","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2023-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138598703","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Integrated Health Monitor COVID-19: A Protocol for a Comprehensive Assessment of the Short- and Long-Term Health Impact of the Pandemic in the Netherlands","authors":"A. van Duinkerken, M. Bosmans, C. Baliatsas, N. Tak, A. Meerdink, N. Jansen, M. de Vetten-Mc Mahon, E. Marra, M. Dückers","doi":"10.3390/mps6060117","DOIUrl":"https://doi.org/10.3390/mps6060117","url":null,"abstract":"Background: The global COVID-19 pandemic has profoundly affected public health. Directly, the pandemic resulted in over 6.6 million deaths, numerous hospitalizations, and widespread illness. The pandemic has also affected health indirectly through government-imposed protective measures, causing decline in mental well-being and increasing social isolation. Unlike previous disasters or crises, the pandemic’s worldwide and enduring impact necessitates a unique research approach. The Network for Health Research in Disasters in the Netherlands responded by initiating a longitudinal, extensive research project called the Integrated Health Monitor COVID-19. The Integrated Health Monitor COVID-19 explores both the direct and indirect health effects of the pandemic at the population level. Methods: The Integrated Health Monitor COVID-19 employs a dual-pronged monitoring strategy alongside an annual literature review. This strategy comprises short-cycle monitoring (conducted quarterly) and long-cycle monitoring (conducted once every one or two years). This comprehensive approach enables the evaluation of health trends during the pandemic, facilitating comparisons with pre-pandemic levels and identification of risk and protective factors. Both monitoring methods incorporate data from surveys and general practice registries. The integration of annual literature reviews with these measurements enables iterative research, while dialogues on policy and practice improvements enhance the knowledge-to-action process. Discussion: Much of the existing knowledge about the potential impact of the COVID-19 pandemic is derived from research on sudden-onset disasters limited to specific geographical areas. This study is anticipated to provide valuable fresh insights into the evolving dynamics of population health and specific vulnerabilities within the ongoing pandemic context.","PeriodicalId":18715,"journal":{"name":"Methods and Protocols","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2023-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138607327","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}