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1.
Genes Dev ; 33(21-22): 1525-1538, 2019 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-31530651

RESUMEN

Cellular homeostasis requires transcriptional outputs to be coordinated, and many events post-transcription initiation can dictate the levels and functions of mature transcripts. To systematically identify regulators of inducible gene expression, we performed high-throughput RNAi screening of the Drosophila Metallothionein A (MtnA) promoter. This revealed that the Integrator complex, which has a well-established role in 3' end processing of small nuclear RNAs (snRNAs), attenuates MtnA transcription during copper stress. Integrator complex subunit 11 (IntS11) endonucleolytically cleaves MtnA transcripts, resulting in premature transcription termination and degradation of the nascent RNAs by the RNA exosome, a complex also identified in the screen. Using RNA-seq, we then identified >400 additional Drosophila protein-coding genes whose expression increases upon Integrator depletion. We focused on a subset of these genes and confirmed that Integrator is bound to their 5' ends and negatively regulates their transcription via IntS11 endonuclease activity. Many noncatalytic Integrator subunits, which are largely dispensable for snRNA processing, also have regulatory roles at these protein-coding genes, possibly by controlling Integrator recruitment or RNA polymerase II dynamics. Altogether, our results suggest that attenuation via Integrator cleavage limits production of many full-length mRNAs, allowing precise control of transcription outputs.


Asunto(s)
Proteínas de Drosophila/genética , Drosophila/genética , Regulación de la Expresión Génica , Metalotioneína/genética , Regiones Promotoras Genéticas/genética , ARN Mensajero/metabolismo , Animales , Línea Celular , Cobre/toxicidad , Endorribonucleasas/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Unión Proteica , División del ARN , Estrés Fisiológico/efectos de los fármacos
2.
Nat Immunol ; 15(12): 1095-7, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25396342

RESUMEN

The combination of machine-learning tools and mass-cytometry measurements of more than 30 protein markers per cell comprehensively maps cell identity in the heterogeneous myeloid cell system and reveals the global effect of deletion of the gene encoding the receptor for the growth factor GM-CSF.


Asunto(s)
Citometría de Flujo/métodos , Células Mieloides/citología , Animales
3.
Plant Cell ; 35(9): 3162-3172, 2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37352127

RESUMEN

The formation of biomolecular condensates through phase separation is an important strategy to compartmentalize cellular functions. While it is now well established that condensates exist throughout eukaryotic cells, how condensates assemble and function on lipid membranes is only beginning to be understood. In this perspective, we highlight work from plant, animal, and yeast model systems showing that condensates assemble on many endomembrane surfaces to carry out diverse functions. In vesicle trafficking, condensation has reported roles in the formation of endocytic vesicles and autophagosomes and in the inactivation of secretory COPII vesicles. We briefly discuss how membranes and membrane lipids regulate the formation and function of membrane-associated condensates. This includes how membranes act as surfaces for condensate assembly, with lipids mediating the nucleation of condensates during endocytosis and other processes. Additionally, membrane-condensate interactions give rise to the biophysical property of "wetting", which has functional importance in shaping autophagosomal and vacuolar membranes. We also speculate on the existence of membrane-associated condensates during cell polarity in plants and discuss how condensation may help to establish functional plasma membrane domains. Lastly, we provide advice on relevant in vitro and in vivo approaches and techniques to study membrane-associated phase separation.


Asunto(s)
Proteínas , Vacuolas , Animales , Proteínas/metabolismo , Membrana Celular/metabolismo , Autofagosomas , Biología
4.
Microbiol Immunol ; 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38961765

RESUMEN

In middle to late 2023, a sublineage of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron XBB, EG.5.1 (a progeny of XBB.1.9.2), is spreading rapidly around the world. We performed multiscale investigations, including phylogenetic analysis, epidemic dynamics modeling, infection experiments using pseudoviruses, clinical isolates, and recombinant viruses in cell cultures and experimental animals, and the use of human sera and antiviral compounds, to reveal the virological features of the newly emerging EG.5.1 variant. Our phylogenetic analysis and epidemic dynamics modeling suggested that two hallmark substitutions of EG.5.1, S:F456L and ORF9b:I5T are critical to its increased viral fitness. Experimental investigations on the growth kinetics, sensitivity to clinically available antivirals, fusogenicity, and pathogenicity of EG.5.1 suggested that the virological features of EG.5.1 are comparable to those of XBB.1.5. However, cryo-electron microscopy revealed structural differences between the spike proteins of EG.5.1 and XBB.1.5. We further assessed the impact of ORF9b:I5T on viral features, but it was almost negligible in our experimental setup. Our multiscale investigations provide knowledge for understanding the evolutionary traits of newly emerging pathogenic viruses, including EG.5.1, in the human population.

5.
Plant Dis ; 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38389385

RESUMEN

In May 2023, pennycress (Thlaspi arvense, L.) lines undergoing seed production in the Walnut Street Greenhouse at the University of Wisconsin-Madison displayed symptoms of chlorosis and black necrotic leaf spots (Fig. S1-A). Lesions eventually enlarged to 1-2 cm in diameter, became necrotic, and coalesced to cover a substantial portion of leaves. Symptoms were observed in ~30% of the pennycress lines adversely affecting overall growth and reproduction. Symptomatic leaves were surface sterilized for 30 seconds in 0.75% sodium hypochlorite, rinsed in sterile deionized water, and bacteria were isolated using three-phase streaking of symptomatic tissue onto KB medium (King et al., 1954). Single colonies of three isolates (creamy white to yellow) from this initial isolation were streaked onto KB medium to obtain pure cultures. Individual colonies were transferred for growth overnight in nutrient broth (Difco) and an equal amount of the broth was added to 30% glycerol in deionized (di) water and stored at -80 °C. To validate Koch's Postulates, bacteria were grown from these stocks on Yeast Dextrose Calcium Carbonate medium (Wilson et al., 1967) and were used to inoculate 5-week-old pennycress plants in the greenhouse. The bacteria were grown for 48 hours at 26°C, suspended in 300 ml of 0.05 M PBS buffer (pH=7.2) for inoculum preparation. Plants were inoculated with three bacterial isolates (approx. 108 CFU/ml) by piercing the mid veins or hydathodes with a sterilized toothpick dipped in the suspension. Inoculated plants were then enclosed in clear plastic bags for 24-48 hours and maintained in the greenhouse at a constant temperature of 26°C with a 16-hour photoperiod. After seven days, water-soaked lesions appeared on the inoculated leaves, eventually developing into the characteristic black spots (Fig. S1-B). DNA from the original isolates was extracted, and 16S PCR and sequencing of the positive bands was done. The negative control only produced brown spots at the site of inoculation (Fig. S1-C). The primer sequences were as follows: 27F: AGAGTTTGATCMTGGCTCAG; 1492R: GGTTACCTTGTTACGACTT (Eden et al., 1991; Weisburg et al., 1991). A BLAST analysis showed that the isolates had an E value of 0.0 to the genus Xanthomonas as well as 100% identity. Amplification and sequencing of the bacterium using gyrB amplicons revealed a 99-100% pairwise match with Xc. To enhance taxonomy resolution and confirm the identity of these isolates, the complete genomes of three samples were sequenced using NextSeq2000 Illumina platform (NCBI bioproject ID PRJNA1040293). Average Nucleotide Identity (ANI) analysis was conducted with representative strains from the Xc species (Dubrow et al., 2022), using PanExplorer (Dereeper et al., 2020) featuring integrated FastANI module (Jain et al., 2018). The isolates genomes exhibited over 98% identity and clustered with that of Xc pv. incanae and Xc pv. barbarae (Fig S2). Further work will be required to identify the pathovar of Xc identified in this study through phenotypic host range assay. This marks the first documented case of Xc in pennycress in the Midwestern US. Given the potential use of pennycress as a cover crop in the region, further investigations are warranted to assess its economic impact on production and develop management strategies.

6.
Plant Dis ; 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36723957

RESUMEN

Bacterial leaf streak (BLS) of barley is caused by the Gram-negative bacterial pathogen Xanthomonas translucens (Sapkota et al. 2020). In 2021, we observed multiple hill plots with BLS symptomatic plants in a barley stripe rust nursery in Vancouver, BC, Canada. We collected 29 leaf samples showing typical BLS symptoms (e.g. necrotic lesions; Fig. S1) and stored at 4 oC until bacterial isolation. Samples were surface-sterilized in 10% NaOCl for 20 sec and rinsed twice. About 1 cm2 of leaf tissue containing BLS characteristic lesions was macerated in 200 µL sterile H2O on a petri dish, incubated for 15 min, and 10 µl of the homogenates was streaked onto Wilbrink's - Boric Acid - Cephalexin (WBC) agar medium. Plates were incubated at 28-30 oC for 48 hrs. Four single colonies were obtained: BC10-1-2a (USask BC10-2a), BC10-1-2b (USask BC10-2b), UBC026 and UBC028. Colonies were grown in WBC broth and gDNA was extracted using E.Z.N.A. Bacterial DNA Kit (Omega Bio-Tek) or DNeasy Plant Pro Kit® (Qiagen) following manufacturer protocols. Genus-level identification was achieved using 16S rRNA sequencing with 27F/1492R primers (Lane 1991) of UBC026 (1,399 bp; NCBI # OP327375) and UBC028 (1,415 bp; NCBI #OP327376). Complete 16S rRNA sequences (1,533bp) of BC10-2a and BC10-2b (1,533 bp) were extracted from the draft whole-genome sequences (WGS) generated in this study. The 16S rRNA sequence homology values of 99.0-100% were recorded between the 4 strains. BLAST analyses of the 16S rRNA sequences to GenBank entries exhibited 99.5-100% similarity values (100% coverage) with the pathotype strains of Xtt DSM 18974T (LT604072) and X. translucens pv. undulosa (Xtu) CFBP 2055 (CP074361). Whole genomes of BC10-2a (JANUQY01) and BC10-2b (JANUQZ01) were sequenced (150-bp; reads 33.1 million; mean coverage 2125x) using NovaSeq Illumina, assembled (Unicycler v0.4.8; Wick et al. 2017) and analyzed to identify the strains to the species-level (Tambong et al. 2021). WGS of strains USask BC10-2a and USask BC10-2b exhibited genome-based DNA-DNA hybridization (dDDH; Meier-Kolthoff et al. 2013) and BLAST-based average nucleotide identity (ANIb; Richter et al. 2015) of 100%. The two strains also showed dDDH and ANIb of 90.4% (species-leel cut-off of 70%) and 98.780% and 98.80% (cut-off of 96%), respectively, with Xtt DSM 18974T (LT604072). In contrast, the WGS of BC10-2a and BC10-2b exhibited only 78.2% dDDH homology values with Xtu CFBP 2055T, suggesting that the strains are genetically more similar to Xtt. The assignment of these strains to Xtt is corroborated by phylogenomic analysis (Fig. S2; Meier-Kolthoff and Göker 2019) that showed the two strains clustering together (100% bootstrap) with the type strain DSM 18974T. These data suggest that these strains are taxonomically members of Xtt. Identification was also confirmed to the genus-level by LAMP assay using published X. translucens primers (Langlois et al. 2017). Pathovar-level identification was confirmed using a cbsA and S8.pep multiplex PCR diagnostic assay (Roman-Reyna et al. 2022). Koch's postulates were verified by greenhouse inoculation via leaf infiltration of UBC026 and UBC028 on 21-day old barley plants (line HB522) using an inoculum of 108 CFU ml-1 followed by re-isolation of the bacteria on WBC. The inoculated plants showed typical BLS symptoms similar to those observed in the field (Fig. S1). Water-inoculated plants had no symptoms. To our knowledge, this is the first published report of BLS of barley in British Columbia.

7.
Behav Brain Sci ; 46: e193, 2023 09 11.
Artículo en Inglés | MEDLINE | ID: mdl-37694910

RESUMEN

Madole & Harden argue that just as the results of randomized controlled trials (RCTs) represent gains in causal knowledge and are useful, despite their limitations, so too are the findings of human behavior genetics. We argue that this analogy is misleading. Unlike RCTs, the results of human behavior genetics research cannot suggest efficacious interventions, nor point toward future research.


Asunto(s)
Conocimiento , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto
8.
BMC Bioinformatics ; 23(1): 534, 2022 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-36494629

RESUMEN

BACKGROUND: The central role of proteins in diseases has made them increasingly attractive as therapeutic targets and indicators of cellular processes. Protein microarrays are emerging as an important means of characterising protein activity. Their accurate downstream analysis to produce biologically significant conclusions is largely dependent on proper pre-processing of extracted signal intensities. However, existing computational tools are not specifically tailored to the nature of these data and lack unanimity. RESULTS: Here, we present the single-channel Protein Microarray Analysis Pipeline, a tailored computational tool for analysis of single-channel protein microarrays enabling biomarker identification, implemented in R, and as an interactive web application. We compared four existing background correction and normalization methods as well as three array filtering techniques, applied to four real datasets with two microarray designs, extracted using two software programs. The normexp, cyclic loess, and array weighting methods were most effective for background correction, normalization, and filtering respectively. CONCLUSIONS: Thus, here we provided a versatile and effective pre-processing and differential analysis workflow for single-channel protein microarray data in form of an R script and web application ( https://metaomics.uct.ac.za/shinyapps/Pro-MAP/ .) for those not well versed in the R programming language.


Asunto(s)
Análisis por Matrices de Proteínas , Programas Informáticos , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Lenguajes de Programación , Flujo de Trabajo , Perfilación de la Expresión Génica/métodos
9.
Pediatr Transplant ; 26(8): e14159, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-34687473

RESUMEN

BACKGROUND: Split liver transplantation (SLT) is a strategy to address organ shortage, but is a technically more demanding procedure than whole graft liver transplantation (LT). We aimed to determine the outcomes following SLT in adult recipients as well as to highlight the impact that having a pediatric LT program has on SLT implementation. METHODS: All SLTs conducted at a single-center from 2010 to 2019 were identified. Patient data was obtained through retrospective review of the electronic medical record. Kaplan-Meier analysis assessed primary outcomes of 1-,3-, and 5-year graft and patient survival. RESULTS: We identified 37 SLTs performed at our institution from 2010 to 2019. Twenty-four donated livers resulted in 21 extended right lobes and 16 left lateral segments for adults and pediatrics recipients, respectively. Eighty-one percent (30/37) of the SLTs were performed after introduction of the combined pediatric program in 2016. 13/24 donor livers were split with both grafts allocated and used at our institution and 92% occurred after introduction of the pediatric program. Graft survival rates at 1-, 3-, and 5-years were 94% in adult recipients and 100% for all time periods in pediatric recipients. Actuarial post-transplant patient survival was 100% at 1-, 3-, and 5-years in both. CONCLUSIONS: The introduction of a pediatric liver transplantation program resulted in more than a fourfold increase in the number of SLTs performed at our center. Increase in allocation and use of both grafts at our institution was also seen.


Asunto(s)
Trasplante de Hígado , Pediatría , Obtención de Tejidos y Órganos , Humanos , Niño , Adulto , Trasplante de Hígado/métodos , Resultado del Tratamiento , Supervivencia de Injerto , Hígado , Estudios Retrospectivos
10.
Plant Dis ; 2022 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-35906777

RESUMEN

In October 2021, strawberry (Fragaria x ananassa) plants (cv. Ruby June) that had dark brown lesions with a diffuse black halo and light brown center and / or dark brown V-shaped necrotic areas often starting from the edge of the leaves were observed in a commercial planting in Washington County. The grower reported 50% incidence in the field when the sample was first submitted and two weeks later reported 80% incidence. The morphology of conidia present on symptomatic leaf tissue was consistent with species of Neopestalotiopsis (Maharachchikumbura et al. 2014). The conidia were ellipsoid to fusiform, five-celled, with three light brown colored median cells and one hyaline apical and basal cell. The apical cells had two to four flexuous appendages and the basal cell had one non-flexuous appendage. Average (N=30) conidia length, not including the appendages, and width was 24.1 ± 2.7 and 6.5 ± 1.4 µm respectively. Two isolates (MLI267-21 and MLI268-21) were purified on potato dextrose agar, producing a dense white mycelial mat with undulate margins. The underside color of the mycelial mat was pinkish-orange. Conidiomata formed randomly in the colonies and extruded black gelatinous spores. To confirm the identity of these isolates the genome of MLI267-21 was sequenced using the NextSeq 2000 Illumina platform and Nextera DNA CD indexes (OSU Applied Microbiology Service Laboratory, Columbus, OH). Partial internal transcribed spacer (ITS) region, ß-tubulin (TUB), and translation elongation factor 1-alpha (TEF-1α) gene sequences (Accession numbers: OM649904, OM649905, and OM649906 respectively) were extracted from the MLI267-21 genome, concatenated, and aligned to published reference sequences. These same genes were amplified and sequenced from MLI268-21. Maximum likelihood phylogenetic analysis performed in IQ-TREE (Minh et al. 2020, Kalyaanamoorthy et al. 2017, Chernomor et al. 2016) with the aligned sequences revealed the clustering of MLI267-21 and MLI268-21 with seven other Neopestalotiopsis isolates, from strawberry (17-43L; Baggio et al. 2021) and pomegranate (GEV3426 to GEV3431; Xavier et al. 2021) leaves in Florida, which form a unique and emerging species group. The ITS, TUB, and TEF-1α sequences from both Ohio isolates were 100% similar to the same sequences from 17-43L and GEV3426 - GEV3431. Pathogenicity tests were performed using MLI267-21 by spray inoculating (~104 spore/ml) four-week-old 'Cabrillo' strawberry plants (n=4) and placing three drops (10µl each) of spore suspension (~104 spore/ml) on the calix area of detached fruit (n=4). Non-inoculated plants and fruit (n= 4 each) served as negative controls. The plants were covered with transparent plastic bags and maintained at 25 °C for 72 hours before the bags were removed (Baggio et al. 2021). Five days post-inoculation, dark brown circular spots on the leaves and petioles were observed on all four inoculated plants and acervuli were observed within the necrotic spots after an additional 72 hours in a moist chamber. Fruits were incubated in a moist chamber at 25 °C and after 72 hours orange-brown lesions formed on the fruit. After five days, fruit were mushy and covered with white mycelia, acervuli, and conidiomata. Neopestalotiopsis disease has been reported on strawberry in Florida (Baggio et al. 2021) and in several South American (Obregon et al. 2018, Hidrobo et al. 2021) and European (Chamorro et al. 2016, Gilardi et al. 2019) countries. The disease can cause rapid plant death when conditions are warm and wet. Research to investigate host susceptibility and to identify effective chemical and biological control has been initiated in Ohio to establish preventative management programs for commercial field operations.

11.
Plant Dis ; 2022 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-36548920

RESUMEN

Winterberries (Ilex verticillata and hybrids) are deciduous species of holly whose branches bearing colorful fruit are cut in late Fall to be used for seasonal decorations. The annual wholesale value of the woody cuts is $1.5 million nationally (NASS, 2019). In June 2021, approximately 80% of the 45 Ilex verticillata 'Maryland Beauty' potted plants, which were maintained in a container yard at The Ohio State University research farm in Columbus, OH, presented leaves with irregular necrotic lesions surrounded by a chlorotic halo. No other symptoms were present on the plants. Bacterial streaming was observed from the lesions using a compound microscope and isolations were performed after surface disinfesting small sections of leaf tissue from the border of the lesions by soaking in 10% bleach for 30 sec, rinsing twice in sterile water, macerating in sterile water, and streaking the suspension on nutrient broth yeast extract agar. Creamy white, circular, smooth, and convex colonies were recovered after incubation at 28°C for 48 h. Bacterial identification of one representative isolate was initially pursued from single colonies of a purified culture using five discriminative phenotypic tests (i.e., LOPAT: "L", levan production; "O", oxidase activity; "P", pectinolytic activity; "A", arginine dehydrolase production; "T", tobacco hypersensitive reaction), which resulted in the L+ O- P- A- T+ profile consistent with the description of Pseudomonas syringae (Lelliott et al. 1996). Molecular identification was performed based on rpoD marker amplification and sequencing using primers PsrpoD FNP1/PsrpoDnprpcr1 (Parkison et al. 2011). NCBI GenBank BLASTn comparison of the rpoD sequence (GenBank Acc. No. OP221440) shared 99.12% identity to P. syringae pv. passiflorae (AB163366.1). Whole genome sequence analysis was conducted to strengthen the classification of the isolate species. To this extent, DNA was sequenced with an iSeq 100 Illumina benchtop sequencer using Illumina DNA Prep kit and iSeq 100 i1 Reagent v2 (Illumina, Inc, REF: 20060060 and 20031371). Illumina Local Run Manager software was used for base calling, demultiplexing, and trimming of the raw reads. Unicycler v0.5.0 was used for de novo assembly of the genome (Wick et al. 2017). The assembled genome size was 5.9 Mb with 959 contigs and 10× coverage (NCBI GenBank Biosample No. SAMN30281368; Acc. No. JANQCB010000000). Average nucleotide identity (ANI) analysis was performed on the server MiGA online (Rodriguez-R et al. 2018). Subgroup identification was inconclusive (p>0.05), positioning this isolate between P. syringae pv. actinidiae (96.45% ANI) and pv. viburni (96.65% ANI) (Rodriguez-R & Konstantinidis, 2016). Both these pathovars cause leaf spots on woody plants such as kiwi and viburnum (Donati et al. 2020; Garibaldi et al. 2005). To confirm pathogenicity, three separate branches on each of two I. verticillata 'Maryland Beauty' potted plants were selected, and 5-7 individual young leaves (>2 weeks from emergence) on each branch were infiltrated with a bacterial suspension (108 CFU/mL) in sterile water (SW) using a needleless syringe by delivering 30-50 µL of suspension per infiltration point. One additional branch per plant was infiltrated with SW to serve as control. Plants were covered with a plastic bag for two days post-inoculation (DPI) and maintained in the laboratory at an average of 23°C. All inoculated leaves showed necrotic lesions two DPI while control leaves remained asymptomatic. To fulfill Koch's postulates, the bacterium was re-isolated from the symptomatic leaves six DPI and confirmed to be identical to the original isolate based on rpoD gene sequencing. To the best of our knowledge, this report signifies the first instance of P. syringae causing bacterial leaf spot on winterberry worldwide. Ornamental plant sales are based primarily on visual appeal; therefore, identification and monitoring of emerging pathogens is essential to ensure the health of the industry.

12.
Behav Brain Sci ; 45: e159, 2022 09 13.
Artículo en Inglés | MEDLINE | ID: mdl-36098439

RESUMEN

We argue that heritability estimates cannot be used to make informed judgments about the populations from which they are drawn. Furthermore, predicting changes in heritability from population changes is likely impossible, and of limited value. We add that the attempt to separate human environments into cultural and non-cultural components does not advance our understanding of the environmental multiplier effect.

13.
J Cell Sci ; 132(7)2019 04 08.
Artículo en Inglés | MEDLINE | ID: mdl-30837286

RESUMEN

The regulation of ion and pH homeostasis of endomembrane organelles is critical for functional protein trafficking, sorting and modification in eukaryotic cells. pH homeostasis is maintained through the activity of vacuolar H+-ATPases (V-ATPases) pumping protons (H+) into the endomembrane lumen, and counter-action by cation/proton exchangers, such as the NHX family of Na+(K+)/H+ exchangers. In plants, V-ATPase activity at the trans-Golgi network/early endosome (TGN/EE) is important for secretory and endocytic trafficking; however, the role of the endosomal antiporters NHX5 and NHX6 in endomembrane trafficking is unclear. Here we show through genetic, pharmacological and live-cell imaging approaches that double knockout of NHX5 and NHX6 results in the impairment of endosome motility and protein recycling at the TGN/EE, but not in the secretion of integral membrane proteins. Furthermore, we report that nhx5 nhx6 mutants are partially insensitive to osmotic swelling of TGN/EE induced by the monovalent cation ionophore monensin, and to late endosomal swelling by the phosphatidylinositol 3/4-kinase inhibitor wortmannin, demonstrating that NHX5 and NHX6 function to regulate the luminal cation composition of endosomes.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Endosomas/metabolismo , Intercambiadores de Sodio-Hidrógeno/metabolismo , Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas , Técnicas de Inactivación de Genes , Homeostasis , Iones/metabolismo , Transporte de Proteínas , Vacuolas/metabolismo , Red trans-Golgi/metabolismo
14.
Stud Hist Philos Sci ; 88: 60-69, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34058686

RESUMEN

In what sense are associations between particular markers and complex behaviors made by genome-wide association studies (GWAS) and related techniques discoveries of, or entries into the study of, the causes of those behaviors? In this paper, we argue that when applied to individuals, the kinds of probabilistic 'causes' of complex traits that GWAS-style studies can point towards do not provide the kind of causal information that is useful for generating explanations; they do not, in other words, point towards useful explanations of why particular individuals have the traits that they do. We develop an analogy centered around Galton's "Quincunx" machine; while each pin might be associated with outcomes of a certain sort, in any particular trial, that pin might be entirely bypassed even if the ball eventually comes to rest in the box most strongly associated with that pin. Indeed, in any particular trial, the actual outcome of a ball hitting a pin might be the opposite of what is usually expected. While we might find particular pins associated with outcomes in the aggregate, these associations will not provide causally relevant information for understanding individual outcomes. In a similar way, the complexities of development likely render impossible any moves from population-level statistical associations between genetic markers and complex behaviors to an understanding of the causal processes by which individuals come to have the traits that they in fact have.


Asunto(s)
Estudio de Asociación del Genoma Completo , Herencia Multifactorial , Causalidad , Estudio de Asociación del Genoma Completo/métodos , Humanos , Fenotipo
15.
Educ Inf Technol (Dordr) ; 26(6): 6747-6769, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33814959

RESUMEN

Student satisfaction is of great significance in online learning, but few studies have explored its determinants in emerging countries. This study investigated the determinants of university students' satisfaction with online learning platforms in China through applying the Technology Satisfaction Model during the COVID-19 pandemic, when an unprecedented amount of learning began to take place online due to the closure of educational institutions. A total of 928 students from five universities in four Chinese provinces or municipalities were surveyed through a purposive sampling technique and analyzed through structural equation modeling and the Rasch model. Findings show that Chinese university students' satisfaction with online learning platforms is directly and indirectly impacted by their computer self-efficacy and the perceived ease of use and usefulness of the platforms. Findings also show that regional differences moderate the associations among these components. The current study adds to theoretical, methodical and practical understanding of university students' satisfaction with using online learning platforms, which have been recognized as irreplaceable emergency educational tools.

16.
Paediatr Anaesth ; 30(8): 852-858, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32485043

RESUMEN

In the midst of the current opioid epidemic, we have encountered more parents who are concerned about the use of opioids in the perioperative setting. Some parents have completely refused the use of opioids on behalf of their children. How should we approach this treatment refusal? This article describes ethical theory related to the refusal of treatment by parents on behalf of their children, and when it is justified to override parental decisions. We propose a decision-making framework that focuses on improving communication and considering alternatives. Assessment of harm to the child from avoiding opioids, as well as potential harms from overriding parental autonomy must be undertaken prior to considering overriding parents.


Asunto(s)
Analgésicos Opioides , Teoría Ética , Niño , Toma de Decisiones , Humanos , Padres , Negativa del Paciente al Tratamiento
17.
Plant Dis ; 2020 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-32945738

RESUMEN

In July 2018, a sample of lavender var. Grosso (Lavandula × intermedia 'Grosso') from Miami County, OH was received by The Ohio State University Vegetable Pathology Laboratory in Wooster. Lavender plants were field-grown in sandy clay soil with plastic mulch under drip irrigation. Disease incidence ranged from 0 to 32% depending on variety. Leaves and stems showed dark necrotic lesions that varied from roughly circular (ca. 0.3 to 0.5 mm diameter) to large coalesced necrotic areas surrounded by a water-soaked halo. Bacterial streaming from lesions was observed microscopically. Leaf tissue pieces (~0.5 cm2) were surface sterilized in 70% ethanol for 30 seconds and rinsed in sterile deionized water. The tissue was sliced aseptically into smaller sections in 100 µl sterile water and the bacterial suspension was streaked on yeast dextrose calcium carbonate agar medium. Ten yellow Xanthomonas-like colonies were selected after 72 hours of incubation at 28ºC in the dark. Strains were gram negative, oxidase negative and caused hypersensitive reactions on Nicotiana benthamiana (L.). All strains were genotyped after whole-cell DNA extraction by BOX-PCR (Louws et al. 1999) and had the same banding profile. Four 8-wk-old lavender plants (Lavandula dentata and Lavandula × ginginsii 'Goodwin Creek Gray') were spray-inoculated with a 106 CFU/ml suspension of strain SM175-2018 in sterile water. Control plants were sprayed with sterile water. Plants were kept in plastic bags for the first 48 h at 28°C with a 14-h photoperiod. Water-soaked necrotic lesions appeared 14 days after inoculation with SM175-2018, whereas mock-inoculated plants did not show symptoms. Bacterial isolation from symptomatic leaf tissue was carried out as described above. The BOX-PCR profile of the re-isolated strain was identical to that of SM175-2018. Multilocus sequence analysis of the housekeeping genes fuyA, gyrB, and rpoD was performed (Accession numbers: MT764834 - MT764836). The resulting concatenated data set was used to perform a phylogenetic analysis using maximum likelihood criteria to evaluate relationships with closely related Xanthomonas spp. using published reference sequences (Young et al. 2008). SM175-2018 was assigned to the X. hortorum clade (Moriniere et al. 2020) with strong bootstrap support. The strain was subjected to whole genome analysis. Genomic DNA was extracted using a QIAGEN Genomic DNA buffer set with genomic-tip 100/G following manufacturer's protocol and sequenced using the iSeq-100 Illumina platform with the Nextera DNA Flex Library Prep protocol kit and Nextera DNA CD indexes. Average nucleotide identity (ANI) analysis was performed with the ANI-Matrix software Enveomics tool (Rodriguez-R and Konstantinidis 2016) using the sequenced genome (NCBI GenBank Biosample no. SAMN11831455) and those of other X. hortorum (Vauterin et al. 1995) bacteria (pvs. hederae, carotae, vitians). SM175-2018 shared a 96% ANI with other X. hortorum strains. X. hortorum is associated with bacterial leaf spot of carrot (Scott and Dung, 2020) and also reported on ornamental plants (Mirik et al. 2010, Oliver et al. 2012, Roberts and Parkinson 2014, Klass et al. 2019), however additional research is needed to establish the host specificity of lavender strains. To our knowledge this is the first report of X. hortorum causing bacterial leaf spot of lavender in Ohio. The disease may negatively impact the yield and quality of flowers used in production of lavender oils and essences.

18.
Inorg Chem ; 58(22): 14939-14980, 2019 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-31668070

RESUMEN

Nanostructured materials are essential building blocks for the fabrication of new devices for energy harvesting/storage, sensing, catalysis, magnetic, and optoelectronic applications. However, because of the increase of technological needs, it is essential to identify new functional materials and improve the properties of existing ones. The objective of this Viewpoint is to examine the state of the art of atomic-scale simulative and experimental protocols aimed to the design of novel functional nanostructured materials, and to present new perspectives in the relative fields. This is the result of the debates of Symposium I "Atomic-scale design protocols towards energy, electronic, catalysis, and sensing applications", which took place within the 2018 European Materials Research Society fall meeting.

19.
Pediatr Dermatol ; 36(3): 360-361, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30828862

RESUMEN

A 14-year-old boy with neurofibromatosis type I (NF1) presented with a painful neurofibroma on his right palm. The lesion was treated with topical sirolimus, resulting in decreased size and pain and improvement in motor function of his hand. This case demonstrates the efficacy of topical sirolimus in the management of neurofibromas in NF1.


Asunto(s)
Inmunosupresores/uso terapéutico , Neurofibroma/tratamiento farmacológico , Neurofibromatosis 1/complicaciones , Sirolimus/uso terapéutico , Neoplasias Cutáneas/tratamiento farmacológico , Administración Cutánea , Adolescente , Humanos , Masculino , Neurofibroma/etiología , Neoplasias Cutáneas/etiología
20.
Euro Surveill ; 24(31)2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31387671

RESUMEN

BackgroundA variety of airline passenger data sources are used for modelling the international spread of infectious diseases. Questions exist regarding the suitability and validity of these sources.AimWe conducted a systematic review to identify the sources of airline passenger data used for these purposes and to assess validation of the data and reproducibility of the methodology.MethodsArticles matching our search criteria and describing a model of the international spread of human infectious disease, parameterised with airline passenger data, were identified. Information regarding type and source of airline passenger data used was collated and the studies' reproducibility assessed.ResultsWe identified 136 articles. The majority (n = 96) sourced data primarily used by the airline industry. Governmental data sources were used in 30 studies and data published by individual airports in four studies. Validation of passenger data was conducted in only seven studies. No study was found to be fully reproducible, although eight were partially reproducible.LimitationsBy limiting the articles to international spread, articles focussed on within-country transmission even if they used relevant data sources were excluded. Authors were not contacted to clarify their methods. Searches were limited to articles in PubMed, Web of Science and Scopus.ConclusionWe recommend greater efforts to assess validity and biases of airline passenger data used for modelling studies, particularly when model outputs are to inform national and international public health policies. We also recommend improving reporting standards and more detailed studies on biases in commercial and open-access data to assess their reproducibility.


Asunto(s)
Aeronaves/estadística & datos numéricos , Enfermedades Transmisibles/epidemiología , Trazado de Contacto , Brotes de Enfermedades , Viaje , Aeropuertos , Humanos , Modelos Teóricos
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