scholarly journals Impact of repeated nasal sampling on detection and quantification of SARS-CoV-2

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Joshua M. Levy ◽  
Jennifer K. Frediani ◽  
Erika A. Tyburski ◽  
Anna Wood ◽  
Janet Figueroa ◽  
...  

AbstractThe impact of repeated sample collection on COVID-19 test performance is unknown. The FDA and CDC currently recommend the primary collection of diagnostic samples to minimize the perceived risk of false-negative findings. We therefore evaluated the association between repeated sample collection and test performance among 325 symptomatic patients undergoing COVID-19 testing in Atlanta, GA. High concordance was found between consecutively collected mid-turbinate samples with both molecular (n = 74, 100% concordance) and antigen-based (n = 147, 97% concordance, kappa = 0.95, CI = 0.88–1.00) diagnostic assays. Repeated sample collection does not decrease COVID-19 test performance, demonstrating that multiple samples can be collected for assay validation and clinical diagnosis.

2013 ◽  
Vol 8 (3) ◽  
pp. 205-212 ◽  
Author(s):  
Richard F. Louie, PhD, FACB ◽  
William J. Ferguson, BS ◽  
Corbin M. Curtis, BS ◽  
John H. Vy, BS ◽  
Chloe S. Tang, BS ◽  
...  

Objective: To characterize the effects of environmental stress on point-of-care (POC) cardiac biomarker testing during a simulated rescue.Design: Multiplex test cassettes for cardiac troponin I (cTnI), brain natriuretic peptide (BNP), CKMB, myoglobin, and D-dimer were exposed to environmental stresses simulating a 24-hour rescue from Hawaii to the Marshall Islands and back. We used Tenney environmental chambers (T2RC and BTRC) to simulate flight conditions (20°C, 10 percent relative humidity) and ground conditions (22.3-33.9°C, 73-77 percent). We obtained paired measurements using stressed versus control (room temperature) cassettes at seven time points (T1-7 with T1,2,6,7 during flight and T3-5 on ground). We analyzed paired differences (stressed minus control) with Wilcoxon signed rank test. We assessed the impact on decision-making at clinical thresholds.Results: cTnI results from stressed test cassettes (n = 10) at T4 (p 0.05), T5 (p 0.01), and T7 (p 0.05) differed significantly from control, when testing samples with median cTnI concentration of 90 ng/L. During the ground rescue, 36.7 percent (11/30) of cTnI measurements from stressed cassettes generated significantly lowered results. At T5, 20 percent (2/10) of cTnI results were highly discrepant—stressed cassettes reported normal results, when control results were 100 ng/L. With sample median concentration of 108 pg/mL, BNP results from stressed test cassettes differed significantly from controls (p 0.05).Conclusion: Despite modest, short-term temperature elevation, environmental stresses led to erroneous results. False negative cTnI and BNP results potentially could miss acute myocardial infarction and congestive heart failure, confounded treatment, and increased mortality and morbidity. Therefore, rescuers should protect POC reagents from temperature extremes.


2021 ◽  
Vol 2 (2) ◽  
pp. 76-86
Author(s):  
Diky Setiawan ◽  
Mochammad Hasymi Somaida

The Corona virus is a virus that originates from China, and spreads rapidly throughout the world andbegan to spread to Indonesia in early March 2020. The impact of Covid-19 has caused losses in all fields,be it economy, education, etc. In the field of education, activities both learning and examinations must bereplaced online due to the impact of the spread of Covid-19. This study aims to determine theeffectiveness of the implementation of UAS which is carried out online using the Google Form applicationmedia at SMP MA'ARIF NU CIMANGGU. This research uses the quantitative survey method whichdescribes the online UAS implementation activities at SMP MA'ARIF NU CIMANGGU during thepandemic. The object consists of 35 student respondents. The data sample collection is done using aquestionnaire / questionnaire containing questions related to the implementation of UAS online using theGoogle Form application at SMP MA ' ARIF NU CIMANGGU. Based on the results of this study, theimplementation of online UAS runs effectively f and good, it can be seen from the results of satisfactorystudent scores. The application used is of course the Googke Form as the main media, and Whatsapp as amedium for interaction between teachers and students. The obstacles experienced are regarding badconnections, limited quota, schedules that frequently change, as well as difficulties in understandingsubject matter.Keywords: Covid-19,impact,effectiveness


2021 ◽  
Author(s):  
Henry Ptok ◽  
Frank Meyer ◽  
Roland S. Croner ◽  
Ingo Gastinger ◽  
Benjamin Garlipp

Summary Objective To analyze data obtained in a representative number of patients with primary rectal cancer with respect to lymph node diagnostics and related tumor stages. Methods In pT2-, pT3-, and pT4 rectal cancer lesions, the impact of investigated lymph nodes on the frequency of pN+ status, the cumulative risk of metachronous distant metastases, and overall survival was studied by means of a prospective multicenter observational study over a defined period of time. Results From 2000 to 2011, the proportion of surgical specimens with ≥ 12 investigated lymph nodes increased significantly, from 73.6% to 93.2% (p < 0.001; the number of investigated lymph nodes from 16.2 to 20.8; p < 0.001). Despite this, the percentage of pN+ rectal cancer lesions varied only non-significantly (39.9% to 45.9%; p = 0.130; median, 44.1%). For pT2-, pT3-, and pT4 rectal cancer lesions, there was an increasing proportion of pN+ findings correlating significantly with the number of investigated lymph nodes up to n = 12 investigated lymph nodes. Only in pT3 rectal cancer was there a significant increase in pN+ findings in case of > 12 lymph nodes (p = 0.001), but not in pT2 (p = 0.655) and pT4 cancer lesions (p = 0.256). For pT3pN0cM0 rectal cancer, the risk of metachronous distant metastases and overall survival did not depend on the number of investigated lymph nodes. Conclusion In rectal cancer, at least n = 12 lymph nodes are to be minimally investigated. The investigation of fewer lymph nodes is associated with a higher risk of false-negative pN0 findings. In particular, in pT3 rectal cancer, the investigation of more than 12 lymph nodes lowers the risk of false-negative pN0 findings. An upstaging effect by the investigation of a possibly maximal number of lymph nodes could not be detected.


2021 ◽  
Vol 11 (5) ◽  
pp. 2365
Author(s):  
Sorinel Căpușneanu ◽  
Dorel Mateș ◽  
Mirela Cătălina Tűrkeș ◽  
Cristian-Marian Barbu ◽  
Adela-Ioana Staraș ◽  
...  

The digital transformation has produced changes in all existing areas of activity worldwide. There are many factors that can influence the intention to use Industry 4.0 processes and solutions and change the behavior of organizations and their business models. The aim of this study is to validate the econometric model on assessing the significant impact of distinct factors on the intention to use Industry 4.0 processes and solutions, the benefits of digital transformation perceived by organizational management and the differences between distinct groups analyzed. The research method used within the quantitative study was the sample survey, using the online questionnaire as a data collection tool. Three hundred forty-seven valid questionnaires were collected and the response rate of the respondents was 64.25%. A new structural model was generated based on the elements of the Unified Theory of Acceptance and Use of Technology (UTAUT). The results of the study indicated that Perceived competitiveness and Perceived risk have a significant impact on Intention to Use Industry 4.0 processes while Perceived vertical networking solutions and Perceived integrated engineering solutions have a significant influence on the Intention to Use Industry 4.0 solutions. In conclusion, there is a positive and significant association between Intention to Use Industry 4.0 solutions and Benefits of Digital Transformation.


Toxins ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 309
Author(s):  
Zhihua Ren ◽  
Pei Gao ◽  
Samuel Kumi Okyere ◽  
Yujing Cui ◽  
Juan Wen ◽  
...  

The objective of this study was to determine the impact of Ageratina adenophora (A. adenophora) on splenic immune function in a rat model. Rats were fed with 10 g/100 g normal feed and an experimental feed, which was composed of 3:7 A. adenophora powder and normal feed for 60 days. On days 14, 28, and 60, subsets of rats (n = 8 rats/group/time point) were selected for blood and spleen tissue sample collection. The results showed that the proportion of CD3+ T cells in the spleen was decreased at day 60 (vs. control). Also, mRNA and protein expression of chemokines CCL21 and CCL19 and functional protein gp38 in spleen decreased significantly versus the control at day 60. In addition, ER-TR7 antigen protein expression was also decreased at day 60. Levels of T-helper (Th)1 cells significantly increased, whereas those of Th2 cells decreased significantly versus the control at day 60 in spleen. The finding revealed that A. adenophora could affect splenic immune function in rats by altering the fibroblast reticulocyte (FRC) network, as well as by causing an imbalance in Th1/Th2 cell ratios. This research provides new insights into potential mechanisms of spleen immunotoxicity due to exposures to A. Adenophora.


2021 ◽  
Vol 9 (2) ◽  
pp. 180
Author(s):  
Lei Du ◽  
Osiris A. Valdez Banda ◽  
Floris Goerlandt ◽  
Pentti Kujala ◽  
Weibin Zhang

Ship collision is the most common type of accident in the Northern Baltic Sea, posing a risk to the safety of maritime transportation. Near miss detection from automatic identification system (AIS) data provides insight into maritime transportation safety. Collision risk always triggers a ship to maneuver for safe passing. Some frenetic rudder actions occur at the last moment before ship collision. However, the relationship between ship behavior and collision risk is not fully clarified. Therefore, this work proposes a novel method to improve near miss detection by analyzing ship behavior characteristic during the encounter process. The impact from the ship attributes (including ship size, type, and maneuverability), perceived risk of a navigator, traffic complexity, and traffic rule are considered to obtain insights into the ship behavior. The risk severity of the detected near miss is further quantified into four levels. This proposed method is then applied to traffic data from the Northern Baltic Sea. The promising results of near miss detection and the model validity test suggest that this work contributes to the development of preventive measures in maritime management to enhance to navigational safety, such as setting a precautionary area in the hotspot areas. Several advantages and limitations of the presented method for near miss detection are discussed.


Author(s):  
Ron M Kagan ◽  
Amy A Rogers ◽  
Gwynngelle A Borillo ◽  
Nigel J Clarke ◽  
Elizabeth M Marlowe

Abstract Background The use of a remote specimen collection strategy employing a kit designed for unobserved self-collection for SARS-CoV-2 RT-PCR can decrease the use of PPE and exposure risk. To assess the impact of unobserved specimen self-collection on test performance, we examined results from a SARS-CoV-2 qualitative RT-PCR test for self-collected specimens from participants in a return-to-work screening program and assessed the impact of a pooled testing strategy in this cohort. Methods Self-collected anterior nasal swabs from employee return to work programs were tested using the Quest Diagnostics SARS-CoV-2 RT-PCR EUA. The Ct values for the N1 and N3 N-gene targets and a human RNase P (RP) gene control target were tabulated. For comparison, we utilized Ct values from a cohort of HCP-collected specimens from patients with and without COVID-19 symptoms. Results Among 47,923 participants, 1.8% were positive. RP failed to amplify for 13/115,435 (0.011%) specimens. The median (IQR) Cts were 32.7 (25.0-35.7) for N1 and 31.3 (23.8-34.2) for N3. Median Ct values in the self-collected cohort were significantly higher than those of symptomatic, but not asymptomatic patients. Based on Ct values, pooled testing with 4 specimens would have yielded inconclusive results in 67/1,268 (5.2%) specimens but only a single false-negative result. Conclusions Unobserved self-collection of nasal swabs provides adequate sampling for SARS-CoV-2 RT-PCR testing. These findings alleviate concerns of increased false negatives in this context. Specimen pooling could be used for this population as the likelihood of false negative results is very low due when using a sensitive, dual-target methodology.


2021 ◽  
Vol 52 (1) ◽  
Author(s):  
Emma T. Helm ◽  
Eric R. Burrough ◽  
Fernando L. Leite ◽  
Nicholas K. Gabler

AbstractLawsonia intracellularis is endemic to swine herds worldwide, however much is still unknown regarding its impact on intestinal function. Thus, this study aimed to characterize the impact of L. intracellularis on digestive function, and how vaccination mitigates these impacts. Thirty-six L. intracellularis negative barrows were assigned to treatment groups (n  =  12/trt): (1) nonvaccinated, L. intracellularis negative (NC); (2) nonvaccinated, L intracellularis challenged (PC); and (3) L. intracellularis challenged, vaccinated (Enterisol® Ileitis, Boehringer Ingelheim) 7 weeks pre-challenge (VAC). On days post-inoculation (dpi) 0 PC and VAC pigs were inoculated with L. intracellularis. From dpi 19–21 fecal samples were collected for apparent total tract digestibility (ATTD) and at dpi 21, pigs were euthanized for sample collection. Post-inoculation, ADG was reduced in PC pigs compared with NC (41%, P  <  0.001) and VAC (25%, P  <  0.001) pigs. Ileal gross lesion severity was greater in PC pigs compared with NC (P  =  0.003) and VAC (P  =  0.018) pigs. Dry matter, organic matter, nitrogen, and energy ATTD were reduced in PC pigs compared with NC pigs (P  ≤  0.001 for all). RNAscope in situ hybridization revealed abolition of sucrase-isomaltase transcript in the ileum of PC pigs compared with NC and VAC pigs (P  <  0.01). Conversely, abundance of stem cell signaling markers Wnt3, Hes1, and p27Kip1 were increased in PC pigs compared with NC pigs (P  ≤  0.085). Taken together, these data demonstrate that reduced digestibility during L. intracellularis challenge is partially driven by abolition of digestive machinery in lesioned tissue. Further, vaccination mitigated several of these effects, likely from lower bacterial burden and reduced disease severity.


2021 ◽  
Vol 95 (3) ◽  
pp. 1103-1116
Author(s):  
Francesco Marchetti ◽  
Gu Zhou ◽  
Danielle LeBlanc ◽  
Paul A. White ◽  
Andrew Williams ◽  
...  

AbstractThe Organisation for Economic Co-Operation and Development Test Guideline 488 (TG 488) uses transgenic rodent models to generate in vivo mutagenesis data for regulatory submission. The recommended design in TG 488, 28 consecutive daily exposures with tissue sampling three days later (28 + 3d), is optimized for rapidly proliferating tissues such as bone marrow (BM). A sampling time of 28 days (28 + 28d) is considered more appropriate for slowly proliferating tissues (e.g., liver) and male germ cells. We evaluated the impact of the sampling time on mutant frequencies (MF) in the BM of MutaMouse males exposed for 28 days to benzo[a]pyrene (BaP), procarbazine (PRC), isopropyl methanesulfonate (iPMS), or triethylenemelamine (TEM) in dose–response studies. BM samples were collected + 3d, + 28d, + 42d or + 70d post exposure and MF quantified using the lacZ assay. All chemicals significantly increased MF with maximum fold increases at 28 + 3d of 162.9, 6.6, 4.7 and 2.8 for BaP, PRC, iPMS and TEM, respectively. MF were relatively stable over the time period investigated, although they were significantly increased only at 28 + 3d and 28 + 28d for TEM. Benchmark dose (BMD) modelling generated overlapping BMD confidence intervals among the four sampling times for each chemical. These results demonstrate that the sampling time does not affect the detection of mutations for strong mutagens. However, for mutagens that produce small increases in MF, sampling times greater than 28 days may produce false-negative results. Thus, the 28 + 28d protocol represents a unifying protocol for simultaneously assessing mutations in rapidly and slowly proliferating somatic tissues and male germ cells.


Sign in / Sign up

Export Citation Format

Share Document