Time Of Sample Collection Research Articles

Facilitating systems-level analyses of all-cause and Covid-mediated sepsis through SeptiSearch, a manually-curated compendium of dysregulated gene sets.

Sepsis is a dysfunctional host response to infection. The syndrome leads to millions of deaths annually (19.7% of all deaths in 2017) and is the cause of most deaths from severe Covid infections. High throughput sequencing or 'omics' experiments in molecular and clinical sepsis research have been widely utilized to identify new diagnostics and therapies. Transcriptomics, quantifying gene expression, has dominated these studies, due to the efficiency of measuring gene expression in tissues and the technical accuracy of technologies like RNA-Seq. Most of these studies seek to uncover novel mechanistic insights into sepsis pathogenesis and diagnostic gene signatures by identifying genes differentially expressed between two or more relevant conditions. However, little effort has been made, to date, to aggregate this knowledge from such studies. In this study we sought to build a compendium of previously described gene sets that combines knowledge gained from sepsis-associated studies. This would enable the identification of genes most associated with sepsis pathogenesis, and the description of the molecular pathways commonly associated with sepsis. PubMed was searched for studies using transcriptomics to characterize acute infection/sepsis and severe sepsis (i.e., sepsis combined with organ failure). Several studies were identified that used transcriptomics to identify differentially expressed (DE) genes, predictive/prognostic signatures, and underlying molecular responses and pathways. The molecules included in each gene set were collected, in addition to the relevant study metadata (e.g., patient groups used for comparison, sample collection time point, tissue type, etc.). After performing extensive literature curation of 74 sepsis-related publications involving transcriptomics, 103 unique gene sets (comprising 20,899 unique genes) from thousands of patients were collated together with associated metadata. Frequently described genes included in gene sets as well as the molecular mechanisms they were involved in were identified. These mechanisms included neutrophil degranulation, generation of second messenger molecules, IL-4 and -13 signaling, and IL-10 signaling among many others. The database, which we named SeptiSearch, is made available in a web application created using the Shiny framework in R, (available at https://septisearch.ca). SeptiSearch provides members of the sepsis community the bioinformatic tools needed to leverage and explore the gene sets contained in the database. This will allow the gene sets to be further scrutinized and analyzed for their enrichment in user-submitted gene expression data and used for validation of in-house gene sets/signatures.

Composition of subgingival microbiota associated with periodontitis and diagnosis of malignancy-a cross-sectional study.

Periodontitis is one of the world's most prevalent infectious conditions, affecting between 25 and 40% of the adult population. It is a consequence of the complex interactions between periodontal pathogens and their products, which trigger the host inflammatory response, chronic inflammation, and tissue destruction. Chronic systemic low-grade inflammation is involved in numerous diseases, and it is also known that long-lasting inflammation and chronic infections predispose one to cancer. Here, we characterized and compared the subgingival microbiota associated with periodontitis and diagnosis of malignancy in a longitudinal 10-year follow-up study. The study was conducted on 50 patients with periodontitis and 40 periodontally healthy individuals. The recorded clinical oral health parameters were periodontal attachment loss (AL), bleeding on probing (BOP), gingival index (GI), probing depth (PD), and plaque index (PI). Subgingival plaque was collected from each participant, from which DNA was extracted, and 16S rRNA gene amplicon sequencing performed. Cancer diagnoses data were collected between the years 2008-2018 from the Swedish Cancer Registry. The participants were categorized based on having cancer at the time of sample collection (CSC), having developed cancer later (DCL), and controls without any cancer. The most abundant phyla across all 90 samples were Actinobacteria, Proteobacteria, Firmicutes, Bacteroidetes, and Fusobacteria. At the genus level, Treponema, Fretibacterium, and Prevotella were significantly more abundant in samples of periodontitis patients compared to non-periodontitis individuals. With regard to samples of cancer patients, Corynebacterium and Streptococcus were more abundant in the CSC group; Prevotella were more abundant in the DCL group; and Rothia, Neisseria, and Capnocytophaga were more abundant in the control group. In the CSC group, we also found that the presence of periodontal inflammation, in terms of BOP, GI, and PLI, significantly correlated with species belonging to the genera Prevotella, Treponema, and Mycoplasma. Our results revealed that several subgingival genera were differentially enriched among the studied groups. These findings underscore the need for further research to fully understand the role that oral pathogens may play in the development of cancer.

Practical Utility of Liquid Biopsies for Evaluating Genomic Alterations in Castration-Resistant Prostate Cancer.

Traditional tissue-based assessments of genomic alterations in castration-resistant prostate cancer (CRPC) can be challenging. To evaluate the real-world clinical utility of liquid biopsies for the evaluation of genomic alterations in CRPC, we preemptively collected available plasma samples and archival tissue samples from patients that were being treated for clinically confirmed CRPC. The cell-free DNA (cfDNA) and tumor tissue DNA were analyzed using the AlphaLiquid®100-HRR panel. Plasma samples from a total of 87 patients were included in this study. Somatic mutations from cfDNA were detected in 78 (89.7%) patients, regardless of the presence of overt metastasis or concomitant treatment given at the time of plasma sample collection. Twenty-three patients were found to have known deleterious somatic or germline mutations in HRR genes from their cfDNA. Archival tissue samples from 33 (37.9%) patients were available for comparative analysis. Tissue sequencing was able to yield an NGS result in only 51.5% of the tissue samples. The general sensitivity of cfDNA for detecting somatic mutations in tissues was 71.8%, but important somatic/germline mutations in HRR genes were found to have a higher concordance (100%). Liquid biopsies can be a reasonable substitute for tissue biopsies in CRPC patients when evaluating genomic alterations.

Investigating the Current Status of SARS-CoV-2 Antibodies in Hospital Staff.

The coronavirus disease 2019 (COVID-19) pandemic caused by SARS-CoV-2 had reported over 676 million cases by March 2023. The main aim of this study is to investigate whether the levels of anti-S and anti-N antibodies could precisely indicate the degree of protection against SARS-CoV-2 and affect the probability or time of contracting COVID-19. In this study, a serosurveillance study was conducted in healthcare workers (HCWs) at a regional hospital in Taiwan to evaluate their antibody levels based on infection and vaccination status. Of 245 HCWs enrolled, all have been vaccinated prior to infection. Of these, 85 participants were infected by SARS-CoV-2, while 160 participants were not infected at the time of blood sample collection. The level of anti-SARS-CoV-2 S antibody was significantly higher in the infected HCWs than in the non-infected participants (p < 0.001). It is worth noting that the mean duration between the administration of the last dose of the vaccine and the occurrence of SARS-CoV-2 infection was 5.61 ± 2.95 months. Our follow-up survey revealed that the non-infected group had significantly higher levels of antibodies compared to the infected group (all p < 0.001). In conclusion, this study suggests that the level of antibodies could serve as a reflection of the protective efficacy against SARS-CoV-2 infection. It has the implication for vaccine decision-making policies in the future.

Plasticity of atypical B cell composition and function in response to malaria

Abstract Atypical B cells are generated during a normal adaptive immune response, yet the role of these cells in protective immunity is still largely unknown. Here, we used chronic Plasmodium falciparum exposure as a model to gain insight into the function and potential heterogeneity of atypical B cells in the immune response to infection. To this end, we performed single-cell sequencing on circulating B cells from malaria-experienced individuals. Based on distinct gene expression signatures, we identified three novel atypical B cell subsets. Each subset had an effector profile that translated to one of previously proposed roles for atypical B cells: i) quiescent cells ii) antigen-presenting cells or iii) antibody-secreting cell precursors. We identified differentially expressed cell surface markers that allowed us to track each atypical B cell subset by flow cytometry. We observed that the relative abundance of each subset was influenced by the timing of sample collection in relation to infection. Additionally, our analysis revealed an enrichment of CXCR3+ atypical B cells in adults as compared to children, suggesting further heterogeneity in the context of age or chronic antigen stimulation. To explore the contribution of atypical B cells in response to malaria, we used antigen-tetramers to identify parasite-specific cells. All three atypical B cell subsets harbored antigen-specific B cells that decreased in frequency in the absence of exposure, confirming their active and transient role in malaria immunity. Finally, preliminary results suggest that the three subsets differ in their ability to secrete antibodies after stimulation, highlighting the cellular heterogeneity and distinct effector functions of atypical B cells. National Institutes of Health predoctoral fellowship F31AI169993 (RR) National Institutes of Health grant R35GM128938 (FA) National Institutes of Health grant R01AI153425 (EB)

Metagenomic next-generation sequencing vs. conventional detection methods for detecting the pulmonary infections.

The absence of proper pathogen treatment in the early stages can result in missing out on treatment chances or the overuse of antibiotics, both of which are the primary factors behind fatalities caused by lung infections. In this study, we aimed to investigate the efficacy of metagenomic next-generation sequencing (mNGS) in comparison to conventional detection methods in detecting infectious pathogens. In this retrospective study, the infection pathogens of 104 patients were examined, and 86 bronchoalveolar lavage fluid (BALF), eight pleural effusions, and ten sputum samples were collected. The conventional detection approaches and mNGS analysis were used to determine the infection pathogen profiles and their detection rates were analyzed. Our study showed that mNGS was more sensitive (89.42%) than the conventional detection methods (56.73%) (p < 0.001), with a 32.69% improvement in sensitivity. The efficacy of mNGS in detecting mixed infections was significantly higher than that of conventional detection methods, with a detection rate of 85.29% compared to 17.65% (p < 0.001). The study demonstrated that mNGS had a higher sensitivity than the conventional detection methods when it came to diagnosing pulmonary infections, making it a potentially useful tool for clinical diagnosis. Combining mNGS with other pathogenic detection techniques can be an effective way to increase the rate of detecting pulmonary infections, as well as to provide guidance for treatment adjustments. Furthermore, the timing of sample collection and antibiotic administration can influence the effectiveness of mNGS when used on BALF specimens.

The Role of Urinary NGAL in the Management of Primary Vesicoureteral Reflux in Children.

Vesicoureteral reflux (VUR) is the most frequent congenital urinary tract malformation and an important risk factor for urinary tract infections (UTIs). Up to 50% of children with VUR may develop reflux nephropathy (RN), and the diagnosis and monitoring of renal scars are invasive and costly procedures, so it is paramount to find a non-invasive and accurate method to predict the risk of renal damage. Neutrophil gelatinase-associated lipocalin (NGAL) has already proven to be a good predictive biomarker in acute kidney injuries, but there are few studies that have investigated the role of NGAL in primary VUR in children. Our aim is to review the predictive value of urine NGAL (uNGAL) as a non-invasive biomarker of RN in children with primary VUR, as well as its ability to predict the evolution of chronic kidney disease (CKD). Based on our analysis of the available original studies, uNGAL can be an accurate and reliable biomarker of RN and its progression to CKD. Some studies suggested a good correlation between VUR severity and uNGAL levels, but other studies found no significant correlation. The relationship between VUR severity and uNGAL levels is likely complex and influenced by factors such as UTIs, the timing of the urine sample collection, and the age and overall health of the patient.

Prevalence of Staphylococcus aureus among Female Patients Attending Rivers State University Teaching Hospital (RSUTH) in Port Harcourt, Nigeria

Objectives: To isolate, identify and determine the prevalence of Staphylococcus aureus among Female Patients attending Rivers State University Teaching Hospital in Port Harcourt using High Vaginal Swab samples.&#x0D; Methods: A cross-sectional study was carried out on total of 103 female patients attending the outpatients department and Antenatal clinic of Rivers State University Teaching Hospital. High Vaginal Swab samples were aseptically collected from 55 non-pregnant and 48 six weeks postpartum women. These were then analysed in the Microbiology Laboratory of the Hospital, following standard microbiological procedures. Questions on age, number of sexual partners, knowledge of vaginal infection, symptomatic case, History of previous infection and treatments was responded to by each participant through the completing of questionnaires. Mannitol Salt Agar (MSA) was used for the isolation of the organism and their phenotypic traits were determined based on their cultural and biochemical characteristics.&#x0D; Results: The study revealed that 25 (24.3%) consisting of 20 (36.4%) non-pregnant women and 5 (10.4%) Postpartum women were positive for Staphylococcus aureus infection. The prevalence of S. aureus among different groups was statistically significant, (P= .002). The highest percentage of S. aureus isolation (36.4%) was found in non-pregnant population. Prevalence of S. aureus was found highest 10 (18.2%) in 21-25 age group among non-pregnant women and none in 26-30 age group among postpartum women. Data obtained from the questionnaires returned showed that 10 (40%) that tested positive for the organism were asymptomatic as at the time of sample collection, had history of previous reproductive tract infection and had previously undergone treatment. &#x0D; Conclusion: The high rate of vaginal Staphylococcal colonisation observed and the positive correlation between Staphylococus aureus prevalence and age, Child delivery status as well as treatment of previous reproductive tract infection seen in the study suggests the need for awareness on the importance of personal hygiene, proper antibiotic usage and regular screening of females within reproductive age.

Norovirus acute gastroenteritis amongst US and European travellers to areas of moderate to high risk of travellers' diarrhoea: a prospective cohort study.

Acute gastroenteritis (AGE) is a major medical condition for travellers worldwide, particularly travellers to low- and middle-income countries. Norovirus (NoV) is the most common cause of viral AGE in older children and adults, but data on prevalence and impact amongst travellers is limited. Prospective, multi-site, observational cohort study conducted 2015-2017, amongst adult international travellers from the US and Europe to areas of moderate to high risk of travel-acquired AGE. Participants provided self-collected pre-travel stool samples and self-reported AGE symptoms whilst travelling. Post-travel stool samples were requested from symptomatic subjects and a sample of asymptomatic travellers within 14days of return. Samples were tested for NoV by RT-qPCR, genotyped if positive and tested for other common enteric pathogens by Luminex xTAG GPP. Of the 1109 participants included, 437 (39.4%) developed AGE symptoms resulting in an overall AGE incidence of 24.7 per 100 person-weeks [95% confidence interval (CI): 22.4; 27.1]. In total, 20 NoV-positive AGE cases (5.2% of those tested) were identified at an incidence of 1.1 per 100 person-weeks (95% CI: 0.7; 1.7). NoV-positive samples belonged mostly to genogroup GII (18, 85.7%); None of the 13 samples sequenced belonged to genotype GII.4. Clinical severity of AGE was higher for NoV-positive than for NoV-negative cases (mean modified Vesikari Score 6.8 vs 4.9) with more cases classified as severe or moderate (25% vs 6.8%). In total, 80% of NoV-positive participants (vs 38.9% in NoV-negative) reported at least moderate impact on travel plans. AGE is a prevalent disease amongst travellers with a small proportion associated with NoV. Post-travel stool sample collection timing might have influenced the low number of NoV cases detected; however, NoV infections resulted in high clinical severity and impact on travel plans. These results may contribute to targeted vaccine development and the design of future studies on NoV epidemiology.

Respiratory viral infections during Hajj seasons

Respiratory viral infections pose a public health concern during mass gathering (MG) events. Sustainable and continuous surveillance of respiratory viruses remains a priority to early identify and prevent potential outbreaks. This article reviews recent literature addressed the prevalence and diversity of circulating respiratory viruses during Hajj pilgrimage, one of the largest planned religious MG events held annually in Saudi Arabia. The variation between studies with respect to study design, sample size, time of sample collection (pre-, during, and pos-Hajj), type of participants (e.g., symptomatic vs. a symptomatic pilgrims), and laboratory procedure was highlighted. The majority of these studies were conducted on the 2019 Hajj season or earlier, prior to the emergence of COVID-19 which had significant impact on the past three Hajj seasons (2020, 2021, and 2022). A summary about key aspects related to organization of Hajj during COVID-19 pandemic and the implementation of exceptional infection control strategies is provided.

Oxygen Reserve Index and Arterial Partial Pressure of Oxygen: Relationship in Open Heart Surgery.

Mild to moderate hyperoxia is potentially beneficial to patients undergoing open heart surgery. Oxygen Reserve Index (ORI) is a novel parameter that correlates to arterial oxygen tension (PaO2) in the hyperoxic range. This prospective study aimed to assess whether the relationship between ORI and PaO2 remains intact in the setting of open-heart surgery. This study included patients undergoing valve, aortic arch and coronary artery bypass grafting(CABG) surgeries, on and off pump, between September 1st 2019 and August 31st 2021. Enrolled patients had arterial blood gas samples collected and analyzed after induction of anesthesia and increases in FiO2 in steps of 0.08 with ORI being recorded at the time of sample collection for cross reference and analysis. ORI values showed a statistically significant correlation with PaO2 values in the 100-200 mmHg range (r = 0.8193, p < 0.001). Additionally, there was a significant correlation between ORI and SpO2 values in the range of 95% and 100% (r = 0.529, p < 0.05). The preserved relationship between ORI and PaO2 in the mild and moderate hyperoxic range can allow more precise titration of oxygen therapy to guide therapy targeting normoxia, mildly and moderately hyperoxia. Additionally, it could have a potential use as an early warning system for impeding hypoxia.

Abstract 2168: Identifying a surrogate biomarker for neuropilin-2 axis in serum of prostate cancer patients

Abstract The purpose of this study is to investigate the correlation of neuropilin-2 (NRP2) and its ligand, vascular endothelial growth factor-C (VEGF-C), with treatment outcomes and resistance in prostate cancer patients. 166 prostate cancer patient serum samples were obtained from the Integrated Cancer Repository for Cancer Research at the University of Nebraska Medical Center. 11 patients were excluded for having a non-prostate genitourinary cancer or more than one concurrent cancer. Patients were categorized as untreated, primary treatment, remission, and secondary treatment based on when their serum sample was collected. Primary treatment indicated current treatment with first-line medical therapy, remission indicated those without evidence of disease after prostatectomy or first-line medical therapy, and secondary therapy indicated second-line treatment currently being given due to treatment-resistant disease. Other variables collected include age, race, ethnicity, prostate-specific antigen (PSA) measured at the time of diagnosis, PSA measured at the time of serum sample collection, Gleason score, and clinical stage using the American Joint Committee on Cancer (AJCC) tumor, node, metastasis (TNM) system. Finally, VEGF-C levels in patient serum were measured using a commercially available ELISA assay (R&amp;D System, Minneapolis, MN). The final data was analyzed using a linear regression model to compare VEGF-C levels between treatment groups, as well as VEGF-C level correlation with each of the other variables collected. Results: All patients were male with an age range of 47 to 85 years, with a mean age of 65.3 years. Most were white (n=135) and non-Hispanic (n=148). VEGF-C levels ranged from 341 pg/ml to 15,983 pg/ml, with a mean of 3,787 pg/ml. Of the 155 patients, 8 were untreated, 26 were in primary therapy, 66 were in remission, and 52 were in secondary therapy. Results showed no statistically significant correlation between VEGF-C levels and PSA at diagnosis, PSA at serum collection, Gleason score, or clinical stage. The most interesting difference between treatment groups was a higher VEGF-C level in remission (mean 63.48 pg/ml) versus secondary therapy (mean 55.31 pg/ml), although this was not statistically significant (p=0.089). Conclusions: Our results indicated that plasma VEGF-C alone is not a prognostic indicator for prostate cancer. Since our studies using cell culture and animal models of prostate cancer have indicated the role of VEGF-C and the NRP2 axis in promoting metastasis and therapy resistance in prostate cancer, it would be useful to determine both the VEGF-C and NRP2 levels in the plasma of the same patients and study whether their level together would predict the outcome of medical therapy. Our ongoing experiments to determine plasma NRP2 levels in this patient cohort should be able to test this hypothesis. Citation Format: Sarah A. Mullen, Dipanwita Das, Samikshan Dutta, Robin R. High, Lynette M. Smith, Benjamin A. Teply, Kaustubh Datta. Identifying a surrogate biomarker for neuropilin-2 axis in serum of prostate cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2168.

MP20-08 RADIOTHERAPY-INDUCED URINARY EXTRACELLULAR VESICLES PREDICT LATE BLADDER TOXICITY IN PROSTATE CANCER PATIENTS

You have accessJournal of UrologyCME1 Apr 2023MP20-08 RADIOTHERAPY-INDUCED URINARY EXTRACELLULAR VESICLES PREDICT LATE BLADDER TOXICITY IN PROSTATE CANCER PATIENTS Ryan Molony, Sarah Kerns, Brian Marples, Emmanuel Oshodi, YuhChyau Chen, and Yi-Fen Lee Ryan MolonyRyan Molony More articles by this author , Sarah KernsSarah Kerns More articles by this author , Brian MarplesBrian Marples More articles by this author , Emmanuel OshodiEmmanuel Oshodi More articles by this author , YuhChyau ChenYuhChyau Chen More articles by this author , and Yi-Fen LeeYi-Fen Lee More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003245.08AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Radiotherapy (RT) is the standard of care for over 50% of prostate cancer (PCa) patients, but up to 25% develop delayed bladder toxicities months to years after treatment. Late radiation cystitis is a dose-limiting toxicity that can cause hematuria and other potentially severe symptoms, leading to further morbidity and decisional regret. Additional work is needed to define early biomarkers of late radiation cystitis in order to better guide patient care. Extracellular vesicles (EVs) are stable membrane-enclosed particles that are released from diverse cell types and present at high levels in biofluid samples, but the relationship between EV biogenesis and the development of late radiation cystitis has not been examined. This study was developed to explore the relationships between late hematuria incidence and urinary and serum EV concentrations in a cohort of PCa patients undergoing RT. METHODS: PCa patients scheduled to receive curative-intent external beam RT with or without brachytherapy boost were enrolled for this study. Longitudinal urine and serum samples were collected on enrollment (pre-treatment) and within 1 week after RT. Patients completed outcome questionnaires containing questions regarding radiation-related symptoms and quality of life at the time of sample collection, 6 months post-RT, and annually after RT for up to 5 years. Demographic, clinical, and treatment data were obtained from electronic medical records. EVs in collected urine and serum samples were quantified through a nanoparticle tracking analysis approach, and EV concentrations at different collection time points were then compared between patients that did and did not develop hematuria. RESULTS: RT was found to significantly increase post-RT urinary EV concentrations relative to pre-RT levels in patients who subsequently developed late hematuria, whereas this induction of enhanced EV biogenesis was not observed in patients who did not develop this toxicity. The same effect was evident but less robust in patient serum samples. Re-examination of prior GWAS data additionally revealed that RT-related hematuria risk was strongly associated with the EV biogenesis-related genes SYTL3 and COG. CONCLUSIONS: Post-treatment EV concentrations in urine samples collected from PCa patients undergoing RT are associated with the future onset of radiation cystitis, providing a promising biomarker that may enable the more-timely treatment of at-risk patients to mitigate the development of late bladder toxicities. Source of Funding: University of Rochester departmental research funding © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e278 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Ryan Molony More articles by this author Sarah Kerns More articles by this author Brian Marples More articles by this author Emmanuel Oshodi More articles by this author YuhChyau Chen More articles by this author Yi-Fen Lee More articles by this author Expand All Advertisement PDF downloadLoading ...

Immortal data: a qualitative exploration of patients’ understandings of genomic data

As ambitions to ‘mainstream’ genetic and genomic medicine in the UK advance, patients are increasingly exposed to information about genomic data. Unlike the results of many other medical investigations which are linked to the time of sample collection, genomic testing provides immortal data that do not change across time, and may have relevance for relatives and generations far beyond the patient’s own lifespan. This immortality raises new ethical challenges for healthcare professionals, patients and families alike, such as ensuring consent for possible future interpretations; determining when genomic data are best sought (at birth, on illness etc) and reinterpreted; and balancing the confidentiality of patients and duties of care towards others. This paper reports on qualitative work exploring the perspectives of patients and relatives participating in genomic testing, and suggests that their engagements with this immortality are shaped by: the contrast between the simplicity of sample provision and information gathered; understandings of heritability; and notions of genomic data as a collective resource. We discuss the implications this holds for practice and argue that the immortality of genomic data must take a more prominent position in patient and healthcare professional interactions.

Prevalence of immunoglobulin G and M to SARS-CoV-2 and other human coronaviruses in The Democratic Republic of Congo, Sierra Leone, and Uganda: A longitudinal study

ObjectivesWe assessed the prevalence of immunoglobulin G (IgG) and IgM against four endemic human coronaviruses and two SARS-CoV-2 antigens among vaccinated and unvaccinated staff at health care centers in Uganda, Sierra Leone, and the Democratic Republic of Congo. MethodsThe government health facility staff who had patient contact in Goma (Democratic Republic of Congo), Kambia District (Sierra Leone), and Masaka District (Uganda) were enrolled. Questionnaires and blood samples were collected at three time points over 4 months. Blood samples were analyzed with the Luminex MAGPIXⓇ. ResultsAmong unvaccinated participants, the prevalence of IgG/IgM antibodies against SARS-CoV-2 receptor-binding domain or nucleocapsid protein at enrollment was 70% in Goma (138 of 196), 89% in Kambia (112 of 126), and 89% in Masaka (190 of 213). The IgG responses against endemic human coronaviruses at baseline were not associated with SARS-CoV-2 sero-acquisition during follow-up. Among the vaccinated participants, those who had evidence of SARS-CoV-2 IgG/IgM at baseline tended to have higher IgG responses to vaccination than those who were SARS-CoV-2 seronegative at baseline, controlling for the time of sample collection since vaccination. ConclusionThe high levels of natural immunity and hybrid immunity should be incorporated into both vaccination policies and prediction models of the impact of subsequent waves of infection in these settings.

Impact of Environmental Factors on the Algae Overgrowth in Pond Water

Algae overgrowth and ecosystem deterioration at the pond located at the Estate of Chadds Ford, Pennsylvania was noticed and potential factors were studied to understand the cause. The environmental factors such as air temperature, sunlight, bacteria, and human activities were considered to be associated with the algae growth. Algae density was monitored through visual observations and water samples were collected and tested for the analysis of bacteria counts and pH of the water according to EPA methods. At the time of each water sample collection, the weather temperature and condition were recorded. The water samples were also observed under a microscope to study the types of algae present. The major species of algae found included Cyanobateria and Chromerida. Algae presence was seasonal and related to temperature and bacteria counts. Bacteria counts drastically increased with the increase of temperature which can be explained because algae and bacteria formed a complex ecosystem. The pH of the water was greater than the EPA water limit of 8.5 when Algae abundance is high during summer. Commonly used nutrients containing T-phosphates and/or O-phosphorous in fertilizers were detected in the water samples which also affected the water pH. In this study, important factors associated with algae overgrowth were identified. Global warming would exacerbate to the pond water and ecosystem deterioration. Human activities such as the long-term application of lawn fertilizers and pesticides that were washed into the pond by rainfall promoted the growth of microorganisms which resulted in the pond water and ecosystem deterioration.

Vancomycin audit in the paediatric population: Patterns of use and appropriateness of therapeutic drug monitoring.

This study aims to investigate prescribing and therapeutic drug monitoring (TDM) practices for vancomycin in paediatrics at the Jordan University Hospital and to determine the impact of inaccuracies in TDM data on dosing decisions. Patterns of vancomycin prescriptions, appropriateness of vancomycin dosing, duration, TDM, and the accuracy of the recorded dosing/sampling times were determined prospectively based on prespecified criteria. Finally, Monte Carlo simulations were undertaken using the mrgsolve-package in R to assess the effect of inaccuracies in recording dosing/sampling times on subsequent dose adjustments. Four hundred forty-two vancomycin courses were analysed. Vancomycin prescriptions were mainly empirical (77.4%). Initial vancomycin doses were appropriate in 73.1% of vancomycin courses. Prolonged use (>5days) was found in 45.7% of admissions with negative cultures; this was related to the diagnosis of suspected sepsis unadjusted-OR: 1.8 (1.1-2.9). TDM was appropriately ordered in 90.7% of concentrations. Discrepancies between the recorded and actual times were noted in 83.9% and 82.7% of audited times of dose administration and sample collection, respectively. Based on simulations, these discrepancies were predicted to result in inappropriate dose adjustment in 37.9% of patients. Inappropriate empirical and prolonged vancomycin use and inaccuracies in recording dosing/sampling times are important areas of improvement in the current clinical practice.

Radial and Oblique Impact Testing of Alpine Helmets onto Snow Surfaces

Recent studies have found that alpine helmets reduce the risk of focal injuries associated with radial impacts, which is likely due to current alpine helmet standards requiring helmets to be drop-tested on flat anvils with only linear acceleration pass criteria. There is a need to evaluate the performance of alpine helmets in more realistic impacts. The current study developed a method to assess the performance of alpine helmets for radial and oblique impacts on snow surfaces in a laboratory setting. Snow samples were collected from a groomed area of a ski slope. Radial impacts were performed as drop tests onto a stationary snow sample. Oblique impacts were performed as drop tests onto a snow sample moving horizontally. For radial impacts, snow sample collection time was found to significantly (p = 0.005) influence mean peak linear headform acceleration with an increase in ambient temperature softening the snow samples. For oblique tests, the recreational alpine sports helmet with a rotation-damping system (RDS) significantly (p = 0.002) reduced mean peak angular acceleration compared to the same helmets with no RDS by approximately 44%. The ski racing helmet also significantly (p = 0.006) reduced mean peak angular acceleration compared to the recreational alpine sports helmet with no RDS by approximately 33%, which was attributed to the smooth outer shell of the ski racing helmet. The current study helps to bridge the knowledge gap between real helmet impacts on alpine snow slopes and laboratory helmet impacts on rigid surfaces.

Abstract P1-13-22: Establishment and characterization of two ER+/HER2- XPDX models developed sequentially before and after acquired resistance to the CDK4/6 inhibitor palbociclib from a patient with metastatic breast cancer

Abstract Background: Several CDK4/6 inhibitors have recently been approved in combination with letrozole or fulvestrant in hormone receptor-positive breast cancer. Although this combination therapy has been found effective in some patients, resistance often develops. To aid in developing new therapies for CDK4/6i-resistant breast cancer and better understand potential resistance mechanisms, we established two XenoSTART Patient-Derived Xenograft (XPDX) models representing ER+/HER2- breast cancer from tissue samples collected seventeen months apart from the same patient before and after palbociclib therapy. These models designated ST4887 and ST4887B were developed and characterized for receptor expression, genomic alterations, and in vivo drug sensitivities toward multiple chemotherapies and targeted agents, including CDK4/6i and fulvestrant. Methods: Models ST4887 and ST4887B were established from metastatic samples collected from a Caucasian female with ER+/HER2- metastatic breast cancer; ST4887 was collected at age 38 from a femur mass biopsy following several treatment regimens including paclitaxel/doxorubicin/cyclophosphamide, radiation and tamoxifen. ST4887B was collected at age 39 from a liver biopsy following treatment with palbociclib/letrozole then palbociclib/fulvestrant, and finally ixabepilone/capecitabine. Both were grown subcutaneously in female athymic nude mice supplemented with exogenous estradiol. The resulting models were passaged, and receptor expression confirmed immunohistochemically; genomic analysis, including WES and RNAseq, was performed to further characterize models. For in vivo studies, both models were evaluated using several chemotherapy and targeted agents alone and in combination including cisplatin, docetaxel, CDK4/6i, fulvestrant, letrozole, olaparib, niraparib, and sacituzumab. In vivo study endpoints included tumor volume and time from treatment initiation with %T/C values and tumor regression reported at study completion; a T/C of ≤ 20% versus control was considered sensitive. Tumor regression (%T/C=&amp;lt; 0) versus Day 0 tumor volume was also reported. Results: ST4887 and ST4887B retained comparable receptor expression (ER=3+/HER2=1+) over tested passages with similar histology compared to archival clinical samples. DNA/RNA sequencing identified several conserved variants including a somatic BRCA2 truncation (BRCA2Y2660*); transcriptomic analysis revealed upregulation of several related genes but no notable fusions. In vivo, both models were insensitive to cisplatin or docetaxel, however ST4887 but not ST4887B was sensitive to fulvestrant or CDK4/6i therapies, although abemaciclib demonstrated some activity toward ST4887B. PARP inhibitors were active toward ST4887 and to a lesser extent ST4887B, while sacituzumab did not have a significant effect on either model. Conclusion: We established and characterized two XPDX models from the same patient before and after acquired resistance to the CDK4/6i palbociclib. Both models were found to retain receptor status and drug sensitivities similar to the patient at the time of sample collection. These models can be utilized as a valuable tool in better understanding acquired resistance to palbociclib. Citation Format: Ashwin Varma, Johnnie Flores, Alyssa Simonson, Anna Stackpole, Kyriakos P. Papadopoulos, Amita Patnaik, Drew Rasco, Muralidhar Beeram, Marisa Sandera, Michael Wick. Establishment and characterization of two ER+/HER2- XPDX models developed sequentially before and after acquired resistance to the CDK4/6 inhibitor palbociclib from a patient with metastatic breast cancer [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P1-13-22.

Do dried blood spots have the potential to support result management processes in routine sports drug testing?-Part 3: LC-MS/MS-based peptide analysis for dried blood spot sampling time point estimation.

Along with the recent acknowledgement of the World Anti-Doping Agency to use dried blood spot (DBS) samples for routine doping control purposes, there have been propositions to use DBS as a matrix that allows regular proactive remotely supervised self-sampling, providing potential longitudinal monitoring of an athlete's exposure to doping agents. However, several organizational aspects have to be considered before implementation, such as the verification of the sample collections time point. Based on a previous untargeted proteomics workflow utilizing liquid chromatography-high-resolution mass spectrometry (LC-HRMS) to identify protein/peptide markers to define the time since deposition of a bloodstain, the aim of the current study was to develop a targeted LC-HRMS/MS analytical method for promising peptidic target analytes. A long-term DBS storage experiment was carried out over a 3-month period (sample collection time points: 0, 2, 4, 7, 14, 21, 28, 42, 56, 70, 84 and 91 days) with DBS samples of 10 volunteers for longitudinal investigation of signal abundance changes of targeted peptide sequences at different storage temperatures (room temperature [RT], 4°C and -20°C). Prior to experimental analysis, LC-HRMS/MS method characteristics were successfully assessed, including intraday precision, carryover and sample extract stability. For estimation of DBS sample collection time points, ratios of two peptides that originate from the same protein prior to tryptic digestion were created. Two targeted peptide area ratios were found to significantly increase after being stored at RT for 28 days, representing potential markers for future use in routine doping controls that contribute to advancing complementary avenues in anti-doping.