Ability to detect antibodies to beak and feather disease virus in blood on filter paper decreases with duration of storage
Background Beak and feather disease virus (BFDV) is a circovirus that infects captive and wild psittacine birds, and is of conservation concern. The haemagglutination inhibition (HI) assay is used to determine antibody titres against BFDV, and the use of dried blood spots (DBS) on filter paper stored at room temperature has been suggested to be an equally valid technique to the use of frozen serum. However, research on other pathogens has found variable results when investigating the longevity of antibodies stored on DBS at room temperature. Consequently, we aimed to test the temporal stability of antibodies to BFDV in DBS samples stored long-term at room temperature. A further goal was to add to the current knowledge of antibody response to naturally acquired BFDV infection in crimson rosellas (Platycercus elegans). Methods Blood was collected from wild P. elegans in Victoria, Australia, that had been live-trapped (n = 9) or necropsied (n = 11). BFDV virus load data were obtained from blood stored in ethanol by real-time quantitative PCR (qPCR); antibody titres were obtained by HI assay from either DBS or serum samples, which had been collected concurrently. All HI assays were performed commercially by the Veterinary Diagnostic Laboratory (VDL) in Charles Sturt University, Australia, who were blind to BFDV blood status. Results HI titres from DBS stored at room temperature declined significantly over time (~80 weeks). By contrast, frozen serum samples assayed after 80 weeks in storage all had high HI titres, only varying up to one dilution step from the initial HI titres obtained from DBS at 3–6 weeks after sampling. Weak HI titres from DBS samples all came back negative when the test was repeated only nine weeks later. Novel high HI titres were reported in P. elegans, and while most birds with high antibody titres had corresponding negative qPCR results, a single subadult presented with high HI titres and virus load simultaneously. Conclusion Detection of antibodies on filter paper stored at room temperature decreases over time, increasing the chances of false negatives in these samples, and in repeated testing of samples with weak HI titres. Consequently, serum should be the preferred sample type to use for seroepidemiological studies on BFDV in parrots and other bird species. When not possible, it may help to store DBS on filter paper at −20 °C or lower. However, prompt testing of DBS samples (e.g., <6 weeks in storage) is recommended pending further research on antibody temporal stability. We also show that P. elegans, especially adults, can produce high antibody titres against BFDV, which may help them resist infection.
Blanch-Lázaro et al. (2021) Ability to detect antibodies to beak and feather disease virus in blood on filter paper decreases with duration of storage. PeerJ 9:e12642 https://doi.org/10.7717/peerj.12642
Utility of olfactory identification test for screening of cognitive dysfunction in community-dwelling older adults
Background There is a need for a large-scale screening test that can be used to detect dementia in older individuals at an early stage. Olfactory identification deficits have been shown to occur in the early stages of dementia, indicating their usefulness in screening tests. This study investigated the utility of an olfactory identification test as a screening test for mild cognitive dysfunction in community-dwelling older people. Methods The subjects were city-dwelling individuals aged over 65 years but under 85 years who had not been diagnosed with dementia or mild cognitive impairment. The Japanese version of the Mild Cognitive Impairment Screen was used to evaluate cognitive function. Based on the results, the subjects were divided into two groups: healthy group and cognitively impaired group. Olfactory identification abilities based on the Japanese version of the University of Pennsylvania Smell Identification Test were compared between the groups. Results There were 182 participants in total: 77 in the healthy group and 105 in the cognitively impaired group. The mean olfactory identification test score of the cognitively impaired group was significantly lower than that of the healthy group. The cognitive impairment test score was significantly correlated with the olfactory identification test score. Conclusions Cross-sectional olfactory identification deficits at baseline in community-dwelling older adults reflected cognitive dysfunction. Assessing olfactory identification ability might be useful as a screening test for mild cognitive dysfunction in community-dwelling older people.
Nogi et al. (2021) Utility of olfactory identification test for screening of cognitive dysfunction in community-dwelling older adults. PeerJ 9:e12656 https://doi.org/10.7717/peerj.12656
Sagittal spine disposition and pelvic tilt during outdoor fitness equipment use and their associations with kinanthropometry proportions in middle-aged and older adults
Background Outdoor fitness training has become popular as a tool for improving the health, especially middle-aged and older adults. For this purpose, outdoor fitness equipment (OFE) have been installed in public areas. However, their safety and effectiveness are still unknown. The aim of the present research was to analyze the sagittal disposition of the spine and pelvic tilt during the use of OFE, and to determine the influence of anthropometric variables on these factors in middle-aged and older adults. Methods Seventy healthy volunteers, 56 women and 14 men (age: 63.14 ± 8.19 years) participated in the study. Sagittal spine disposition and pelvic tilt were measured using a Spinal Mouse®, in the relaxed standing position, and during the use of the OFE. In addition, kinanthropometry variables were also measured according to the guidelines of the International Society for the Advancement of Kinanthropometry. Results Regarding thoracic kyphosis, a significant decrease was found in thoracic kyphosis in the initial position (IP) in single bonny rider (SBR) (p = 0.006) and row (p = 0.046), and a significant increase in the final position (FP) in the row (p = 0.011), surfboard (p < 0.001) and air walker (p = 0.027) machines. In relation to the lumbar curvature and pelvic tilt, a significant decrease in lumbar lordosis and a decrease in pelvic anteversion were observed in the IP and FP in SBR and row; and in the bike (p < 0.001) machine. In the surfboard machine, a significant decrease in lumbar lordosis was found (p = 0.002), with no changes in pelvic tilt. According to the multiple linear regression analysis, the subjects with a higher cormic index and height were more at risk of increasing their thoracic kyphosis, decreasing lumbar lordosis and/or decreasing pelvic anteversion towards pelvic retroversion. Conclusions Middle-aged and older adults show spinal misalignments when using the OFE with respect to the standing position, showing a decrease in the thoracic kyphosis in IP of SBR and ROW, and a significant increase in the surfboard and air walker, and in the FP of Row, in the lumbar lordosis in all the OFE in sitting and some in standing, and in the pelvic anteversion in all the OFE in sitting. The variables height and the cormic index explained most of the changes in sagittal spine disposition.
Abelleira-Lamela et al. (2021) Sagittal spine disposition and pelvic tilt during outdoor fitness equipment use and their associations with kinanthropometry proportions in middle-aged and older adults. PeerJ 9:e12657 https://doi.org/10.7717/peerj.12657
Multiple comparisons of precipitation variations in different areas using simultaneous confidence intervals for all possible ratios of variances of several zero-inflated lognormal models
Flash flooding and landslides regularly cause injury, death, and homelessness in Thailand. An advancedwarning system is necessary for predicting natural disasters, and analyzing the variability of daily precipitation might be usable in this regard. Moreover, analyzing the differences in precipitation data among multiple weather stations could be used to predict variations in meteorological conditions throughout the country. Since precipitation data in Thailand follow a zero-inflated lognormal (ZILN) distribution, multiple comparisons of precipitation variation in different areas can be addressed by using simultaneous confidence intervals (SCIs) for all possible pairwise ratios of variances of several ZILN models. Herein, we formulate SCIs using Bayesian, generalized pivotal quantity (GPQ), and parametric bootstrap (PB) approaches. The results of a simulation study provide insight into the performances of the SCIs. Those based on PB and the Bayesian approach via probability matching with the beta prior performed well in situations with a large amount of zero-inflated data with a large variance. Besides, the Bayesian based on the reference-beta prior and GPQ SCIs can be considered as alternative approaches for small-to-large and medium-to-large sample sizes from large population, respectively. These approaches were applied to estimate the precipitation variability among weather stations in lower southern Thailand to illustrate their efficacies.
Maneerat et al. (2021) Multiple comparisons of precipitation variations in different areas using simultaneous confidence intervals for all possible ratios of variances of several zero-inflated lognormal models. PeerJ 9:e12659 https://doi.org/10.7717/peerj.12659
miR-15a-5p regulates myocardial fibrosis in atrial fibrillation by targeting Smad7
Background At present, there is no effective treatment for myocardial fibrosis in atrial fibrillation (AF). It is reported that miR-15a-5p is abnormally expressed in AF patients but its specific role remains unclear. This study aims to investigate the effect of miR-15a-5p in myocardial fibrosis. Methods Left atrial appendage (LAA) tissues were collected from AF and non-AF patients. In lipopolysaccharide (LPS) stimulated H9C2 cells, miR-15a-5p mimic, inhibitor, pcDNA3.1-Smad7 and small interfering RNA-Smad7 (siRNA-Smad7) were respectively transfected to up-regulate or down-regulate the intracellular expression levels of miR-15a-5p and Smad7. Quantitative real-time polymerase chain reaction (qRT-PCR) and western blot (WB) were used to determine the expression levels of miR-15a-5p, Smad7, transforming growth factor β1 (TGF-β1) and collagen I. Cell counting kit-8 (CCK-8) and ethylene deoxyuridine (EdU) were used to determine cell viability and proliferation capacity, respectively. Dual-luciferase was used to detect whether miR-15a-5p interacted with Smad7, hydroxyproline (HYP) and Hematoxylin-Eosin (HE) staining were used to detect tissue fibrosis. Results The expression levels of miR-15a-5p, TGF-β1 and collagen I were up-regulated, while Smad7 was down-regulated in AF tissues and LPS-stimulated cells. MiR-15a-5p mimic can inhibit the expression of Smad7, and the dual-luciferase experiment confirmed their interaction. MiR-15a-5p inhibitor or pcDNA3.1-Smad7 can inhibit LPS-induced fibrosis and cell proliferation, while siRNA-Smad7 can reverse the changes caused by miR-15a-5p inhibitor. Conclusion We combined clinical studies with LPS-stimulated H9C2 cell model to validate the role of miR-15a-5p in the regulation of Smad7 and fibrosis. Taken together, the miR-15a-5p/Smad7 pathway might be a potential target for AF therapy.
He et al. (2021) miR-15a-5p regulates myocardial fibrosis in atrial fibrillation by targeting Smad7. PeerJ 9:e12686 https://doi.org/10.7717/peerj.12686
Light intensity drives different growth strategies in two duckweed species: Lemna minor L. and Spirodela polyrhiza (L.) Schleiden
Duckweed species Lemna minor and Spirodela polyrhiza are clonal plants with vegetative organs reduced to a frond and a root in L. minor or a frond and several roots in S. polyrhiza. They reproduce vegetatively by relatively rapid multiplication of their fronds. The habit of S. polyrhiza (large fronds with up to 21 roots) makes it a strong competitor among representatives of the family Lemnaceae, probably due to different resource-use strategies compared to small duckweed. In our study, light was the resource that affected the plants before and during the laboratory experiment. We sampled the plants from natural habitats differing in light conditions (open and shady) and grew them for 16 days in a thermostatic growth room at 22 °C under a 16:8 photoperiod and three light intensities (125, 236, 459 µmol photons m–2 s–1) to investigate the trade-off between frond enlargement and multiplication. Both species from the open habitat had higher growth rates based on the frond numbers and on surface area of fronds compared to plants from the shady habitat. They adopted different species-specific strategies in response to the experimental light conditions. The species size affected the growth rates in L. minor and S. polyrhiza. Spirodela polyrhiza grew slower than L. minor, but both species grew fastest at medium light intensity (236 µmol m–2 s–1). Lemna minor maintained the growth rates at high light intensity, while S. polyrhiza slowed down. Spirodela polyrhiza responded to deteriorating light conditions by increasing its frond surface area, thus optimising light capture. Lemna minor from the shady habitat enhanced light harvest by increasing chlorophyll a concentration, but did not invest more in frond enlargement than L. minor from the open habitat. Under shady conditions, S. polyrhiza is likely to achieve an advantage over L. minor due to the larger frond size of the former. Our findings suggest the existence of a trade-off between size and number in duckweed.
Strzałek et al. (2021) Light intensity drives different growth strategies in two duckweed species: Lemna minor L. and Spirodela polyrhiza (L.) Schleiden. PeerJ 9:e12698 https://doi.org/10.7717/peerj.12698
Palatal mucosa thickness and palatal neurovascular bundle position evaluation by cone-beam computed tomography—retrospective study on relationships with palatal vault anatomy
Background Measuring the thickness of the palatal mucosa at the planning of the surgical procedure is an important step in order to obtain the maximum width and thickness of the graft from the appropriate area. The aim of this study is to determine whether there is a relationship between palatal angle (PA) or palatal depth (PD) and palatal mucosa thickness (PMT) or palatal neurovascular bundle distance (PNBD). Methods PMT, PNBD, PD and PA were measured on cone-beam computed tomography (CBCT) images of maxillary posterior region of 200 male and 200 female patients. The mean of all parameters according to gender was compared and the significance of the difference detected between groups was evaluated. Potential relationship between PMT or PNBD and PA or PD was also evaluated. Results In females, the palatal mucosa was significantly thinner at all tooth regions (p < 0.005), and PNBD was lower only at the level of the second molar (p < 0.001). In addition, it was found that there was a significant inverse correlation between the palatal depth value and the palatal mucosal thickness, and palatal depth was correlated with the palatal neurovascular bundle distance (p ≤ 0.001). Discussion Consistent with previous studies, it was observed that the thickest mucosa in the palatal region was located in the region of the premolar teeth, and women had thinner palatal mucosa. In addition, in patients with a deeper palate vault, the palatal mucosa was thinner, but the palatal neurovascular bundle was more distant from the cemento-enamel junction.
Karadag et al. (2021) Palatal mucosa thickness and palatal neurovascular bundle position evaluation by cone-beam computed tomography—retrospective study on relationships with palatal vault anatomy. PeerJ 9:e12699 https://doi.org/10.7717/peerj.12699
Methodological recommendations for assessing scleractinian and octocoral recruitment to settlement tiles
Quantifying recruitment of corals is important for evaluating their capacity to recover after disturbances through natural processes, yet measuring recruitment rates in situ is challenging due to the minute size of the study organism and the complexity of benthic communities. Settlement tiles are widely used in studies of coral recruitment because they can be viewed under a microscope to enhance accuracy, but methodological choices such as the rugosity of tiles used and when and how to scan tiles for recruits post-collection may cause inconsistencies in measured recruitment rates. We deployed 2,880 tiles with matching rugosity on top and bottom surfaces to 30 sites along the Florida Reef Tract for year-long saturations during a three year study. We scanned the top and bottom surfaces of the same tiles for scleractinian recruits before (live scans) and after treating tiles with sodium hypochlorite (corallite scans). Recruit counts were higher in corallite than live scans, indicating that scleractinian recruitment rates should not be directly compared between studies using live scans and those scanning tiles which have been processed to remove fouling material. Recruit counts also were higher on tile tops in general, but the proportion of settlement to the top and bottom surfaces varied significantly by scleractinian family. Thus, biases may be introduced in recruitment datasets by differences in tile rugosity or by only scanning a subset of tile surfaces. Finally, we quantified octocoral recruitment during live scans and found they preferentially settled to tile tops. We recommend that recruitment tile studies include corallite scans for scleractinian skeletons, deploy tiles with matching rugosity on top and bottom surfaces, and scan all tile surfaces.
Harper et al. (2021) Methodological recommendations for assessing scleractinian and octocoral recruitment to settlement tiles. PeerJ 9:e12549 https://doi.org/10.7717/peerj.12549
Inhibition of LINK-A lncRNA overcomes ibrutinib resistance in mantle cell lymphoma by regulating Akt/Bcl2 pathway
Ibrutinib, a bruton tyrosine kinase (BTK) inhibitor which suppresses B-cell receptor signaling, has remarkably improved the outcome of patients with mantle cell lymphoma (MCL). However, approximately 33% of MCL patients have primary Ibrutinib resistance, and acquired Ibrutinib resistance is nearly universal. Long intergenic non-coding RNA for kinase activation (LINK-A) exerts oncogenic role in different types of tumors, but the role of LINK-A in intrinsic ibrutinib resistance in MCL is still unclear. Here, LINK-A expression level was first assessed using quantitative Real-time PCR (qPCR) and immunofluorescence analysis in five MCL cell lines. The effect of LINK-A on regulating MCL cells viability and apoptosis was assayed using CCK-8 and TdT-mediated dUTP nick end labeling (TUNEL) assay, respectively. The association of LINK-A with AKT activation and B cell lymphoma 2 (Bcl2)expression was evaluated using qPCR and western blot analysis. We found that LINK-A level was elevated in Ibrutinib-resistant MCL cell lines (Mino, REC-1, MAVER-1, and Granta-519) compared to Ibrutinib-sensitive MCL cell lines (Jeko-1). Functionally, LINK-A overexpression in Jeko-1 cells enhanced cell viability and repressed Ibrutinib-induced cell apoptosis. LINK-A knockdown in MAVER-1 cells decreased cell viability and further accelerated Ibrutinib-induced cell apoptosis. LINK-A overexpression enhanced Bcl2 expression in Jeko-1 cells, and Bcl2 inhibition blocked the effect of LINK-A on increasing cell viability in the presence of Ibrutinib. On the contrary, LINK-A knockdown reduced Bcl2 expression in MAVER-1 cells, and Bcl2 overexpression damaged the role of LINK-A inhibition in regulating cell viability. Mechanistically, LINK-A positively regulated the activation of AKT signaling, and inhibition of AKT signaling destroyed LINK-A-induced increased of Bcl2 and resulted in a subsequent suppression of cell viability. Taken together, the current results demonstrate that LINK-A inhibition overcomes Ibrutinib resistance in MCL cells by regulating AKT/Bcl2 pathway.
Zhang et al. (2021) Inhibition of LINK-A lncRNA overcomes ibrutinib resistance in mantle cell lymphoma by regulating Akt/Bcl2 pathway. PeerJ 9:e12571 https://doi.org/10.7717/peerj.12571
Characterizing the Type 6 Secretion System (T6SS) and its role in the virulence of avian pathogenic Escherichia coli strain APECO18
Avian pathogenic E. coli is the causative agent of extra-intestinal infections in birds known as colibacillosis, which can manifest as localized or systemic infections. The disease affects all stages of poultry production, resulting in economic losses that occur due to morbidity, carcass condemnation and increased mortality of the birds. APEC strains have a diverse virulence trait repertoire, which includes virulence factors involved in adherence to and invasion of the host cells, serum resistance factors, and toxins. However, the pathogenesis of APEC infections remains to be fully elucidated. The Type 6 secretion (T6SS) system has recently gained attention due to its role in the infection process and protection of bacteria from host defenses in human and animal pathogens. Previous work has shown that T6SS components are involved in the adherence to and invasion of host cells, as well as in the formation of biofilm, and intramacrophage bacterial replication. Here, we analyzed the frequency of T6SS genes hcp, impK, evpB, vasK and icmF in a collection of APEC strains and their potential role in virulence-associated phenotypes of APECO18. The T6SS genes were found to be significantly more prevalent in APEC than in fecal E. coli isolates from healthy birds. Expression of T6SS genes was analyzed in culture media and upon contact with host cells. Mutants were generated for hcp, impK, evpB, and icmF and characterized for their impact on virulence-associated phenotypes, including adherence to and invasion of host model cells, and resistance to predation by Dictyostelium discoideum. Deletion of the aforementioned genes did not significantly affect adherence and invasion capabilities of APECO18. Deletion of hcp reduced resistance of APECO18 to predation by D. discoideum, suggesting that T6SS is involved in the virulence of APECO18.
de Oliveira et al. (2021) Characterizing the Type 6 Secretion System (T6SS) and its role in the virulence of avian pathogenic Escherichia coli strain APECO18. PeerJ 9:e12631 https://doi.org/10.7717/peerj.12631