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21.
Edmond Wonkam-Tingang Isabelle Schrauwen Kevin K Esoh Thashi Bharadwaj Liz M Nouel-Saied Anushree Acharya Abdul Nasir Suzanne M Leal Ambroise Wonkam 《Experimental biology and medicine (Maywood, N.J.)》2021,246(13):1524
Approximately half of congenital hearing impairment cases are inherited, with non-syndromic hearing impairment (NSHI) being the most frequent clinical entity of genetic hearing impairment cases. A family from Cameroon with NSHI was investigated by performing exome sequencing using DNA samples obtained from three family members, followed by direct Sanger sequencing in additional family members and controls participants. We identified an autosomal dominantly inherited novel missense variant [NM_001174116.2:c.918G>T; p.(Q306H)] in DMXL2 gene (MIM:612186) that co-segregates with mild to profound non-syndromic sensorineural hearing impairment . The p.(Q306H) variant which substitutes a highly conserved glutamine residue is predicted deleterious by various bioinformatics tools and is absent from several genome databases. This variant was also neither found in 121 apparently healthy controls without a family history of hearing impairment , nor 112 sporadic NSHI cases from Cameroon. There is one previous report of a large Han Chinese NSHI family that segregates a missense variant in DMXL2. The present study provides additional evidence that DMXL2 is involved in hearing impairment etiology, and we suggest DMXL2 should be considered in diagnostic hearing impairment panels. 相似文献
22.
Rita Barallon Steven R. Bauer John Butler Amanda Capes-Davis Wilhelm G. Dirks Eugene Elmore Manohar Furtado Margaret C. Kline Arihiro Kohara Georgyi V. Los Roderick A. F. MacLeod John R. W. Masters Mark Nardone Roland M. Nardone Raymond W. Nims Paul J. Price Yvonne A. Reid Jaiprakash Shewale Gregory Sykes Anton F. Steuer Douglas R. Storts Jim Thomson Zenobia Taraporewala Christine Alston-Roberts Liz Kerrigan 《In vitro cellular & developmental biology. Animal》2010,46(9):727-732
Cell misidentification and cross-contamination have plagued biomedical research for as long as cells have been employed as research tools. Examples of misidentified cell lines continue to surface to this day. Efforts to eradicate the problem by raising awareness of the issue and by asking scientists voluntarily to take appropriate actions have not been successful. Unambiguous cell authentication is an essential step in the scientific process and should be an inherent consideration during peer review of papers submitted for publication or during review of grants submitted for funding. In order to facilitate proper identity testing, accurate, reliable, inexpensive, and standardized methods for authentication of cells and cell lines must be made available. To this end, an international team of scientists is, at this time, preparing a consensus standard on the authentication of human cells using short tandem repeat (STR) profiling. This standard, which will be submitted for review and approval as an American National Standard by the American National Standards Institute, will provide investigators guidance on the use of STR profiling for authenticating human cell lines. Such guidance will include methodological detail on the preparation of the DNA sample, the appropriate numbers and types of loci to be evaluated, and the interpretation and quality control of the results. Associated with the standard itself will be the establishment and maintenance of a public STR profile database under the auspices of the National Center for Biotechnology Information. The consensus standard is anticipated to be adopted by granting agencies and scientific journals as appropriate methodology for authenticating human cell lines, stem cells, and tissues. 相似文献
23.
Joel H. Otero Beáta Lizák Linda M. Hendershot 《Seminars in cell & developmental biology》2010,21(5):472-478
BiP is the mammalian endoplasmic reticulum (ER) Hsp70 orthologue that plays a major role in all functions of this organelle including the seemingly opposing functions of aiding the maturation of unfolded nascent proteins and identifying and targeting chronically unfolded proteins for degradation. The recent identification of mammalian BiP co-factors combined with delineation of the ER degradation machinery and data suggesting that the ER is subdivided into unique regions helps explain how these different functions can occur in the same organelle and raises some unresolved issues. 相似文献
24.
25.
Sebastian Hin Benjamin Lopez-Jimena Mohammed Bakheit Vanessa Klein Seamus Stack Cheikh Fall Amadou Sall Khalid Enan Mohamed Mustafa Liz Gillies Viorel Rusu Sven Goethel Nils Paust Roland Zengerle Sieghard Frischmann Manfred Weidmann Konstantinos Mitsakakis 《PLoS neglected tropical diseases》2021,15(2)
BackgroundIn this work, a platform was developed and tested to allow to detect a variety of candidate viral, bacterial and parasitic pathogens, for acute fever of unknown origin. The platform is based on a centrifugal microfluidic cartridge, the LabDisk (“FeverDisk” for the specific application), which integrates all necessary reagents for sample-to-answer analysis and is processed by a compact, point-of-care compatible device.Methodology/Principal findingsA sample volume of 200 μL per FeverDisk was used. In situ extraction with pre-stored reagents was achieved by bind-wash-elute chemistry and magnetic particles. Enzymes for the loop-mediated isothermal amplification (LAMP) were pre-stored in lyopellet form providing stability and independence from the cold chain. The total time to result from sample inlet to read out was 2 h. The proof-of-principle was demonstrated in three small-scale feasibility studies: in Dakar, Senegal and Khartoum, Sudan we tested biobanked samples using 29 and 9 disks, respectively; in Reinfeld, Germany we tested spiked samples and analyzed the limit of detection using three bacteria simultaneously spiked in whole blood using 15 disks. Overall during the three studies, the FeverDisk detected dengue virus (different serotypes), chikungunya virus, Plasmodium falciparum, Salmonella enterica Typhi, Salmonella enterica Paratyphi A and Streptococcus pneumoniae.Conclusions/SignificanceThe FeverDisk proved to be universally applicable as it successfully detected all different types of pathogens as single or co-infections, while it also managed to define the serotype of un-serotyped dengue samples. Thirty-eight FeverDisks at the two African sites provided 59 assay results, out of which 51 (86.4%) were confirmed with reference assay results. The results provide a promising outlook for future implementation of the platform in larger prospective clinical studies for defining its clinical sensitivity and specificity. The technology aims to provide multi-target diagnosis of the origins of fever, which will help fight lethal diseases and the incessant rise of antimicrobial resistance. 相似文献
26.
Mitochondrial DNA and the peopling of South America 总被引:1,自引:0,他引:1
Lewis CM Lizárraga B Tito RY López PW Iannacone GC Medina A Martínez R Polo SI De La Cruz AF Cáceres AM Stone AC 《Human biology; an international record of research》2007,79(2):159-178
The initial peopling of South America is largely unresolved, in part because of the unique distribution of genetic diversity in native South Americans. On average, genetic diversity estimated within Andean populations is higher than that estimated within Amazonian populations. Yet there is less genetic differentiation estimated among Andean populations than estimated among Amazonian populations. One hypothesis is that this pattern is a product of independent migrations of genetically differentiated people into South America. A competing hypothesis is that there was a single migration followed by regional isolation. In this study we address these hypotheses using mtDNA hypervariable region 1 sequences representing 21 South American groups and include new data sets for four native Peruvian communities from Tupe, Yungay, and Puno. An analysis of variance that compared the combined data from western South America to the combined data from eastern South America determined that these two regional data sets are not significantly different. As a result, a migration from a single source population into South America serves as the simplest explanation of the data. 相似文献
27.
J Athene Lane Joanne Howson Jenny L Donovan John R Goepel Daniel J Dedman Liz Down Emma L Turner David E Neal Freddie C Hamdy 《BMJ (Clinical research ed.)》2007,335(7630):1139
Objective To investigate the feasibility of testing for prostate cancer and the prevalence and characteristics of the disease in unselected young men.Design Prospective cohort nested within a randomised controlled trial, with two years of follow-up.Setting Eight general practices in a UK city.Participants 1299 unselected men aged 45-49.Intervention Prostate biopsies for participants with a prostate specific antigen level of 1.5 ng/ml or more and the possibility of randomisation to three treatments for those with localised prostate cancer.Main outcome measures Uptake of testing for prostate specific antigen; positive predictive value of prostate specific antigen; and prevalence of prostate cancer, TNM disease stage, and histological grade (Gleason score).Results 442 of 1299 men agreed to be tested for prostate specific antigen (34%) and 54 (12%) had a raised level. The positive predictive value for prostate specific antigen was 21.3%. Ten cases of prostate cancer were detected (2.3%) with eight having at least two positive results in biopsy cores and three showing perineural invasion. One tumour was of high volume (cT2c), Gleason score 7, with a positive result on digital rectal examination; nine tumours were cT1c, Gleason score 6, and eight had a negative result on digital rectal examination. Five of the nine eligible participants (55%) agreed to be randomised. No biochemical disease progression in the form of a rising prostate specific antigen level occurred in two years of follow-up.Conclusions Men younger than 50 will accept testing for prostate cancer but at a much lower rate than older men. Using an age based threshold of 1.5 ng/ml, the prevalence of prostate cancer was similar to that in older men (3.0 ng/ml threshold) and some cancers of potential clinical significance were found.Trial registration Current Controlled Trials ISRCTN20141297 相似文献
28.
Liu N Academia K Rubio T Wehr T Yeck T Jordan L Hamby K Paulus A 《Cell motility and the cytoskeleton》2007,64(2):110-120
Actin-binding proteins regulate the dynamic structure and function of actin filaments in the cell. Much is known about how manipulation of the actin-binding proteins affects the structure and function of actin filaments; however, little is known about how manipulation of actin in the cell affects actin-binding proteins. We addressed this question by utilizing two technologies: RNA interference and 2-dimensional gel electrophoresis. We knocked down beta-actin expression in HeLa cells using short interfering RNA and applied 2-DGE to examine alterations in the HeLa cell proteome. We revealed a 2-5 fold increases of four protein spots on 2-D gels and identified these proteins by mass spectrometry. Three of the four proteins were actin-binding proteins, including cofilin, which promotes both disassembly and assembly of actin filaments but becomes inactivated when phosphorylated. Further examination revealed that the cofilin total protein level barely increased, but the phosphorylated cofilin level increased dramatically in HeLa cells after beta-actin siRNA treatment. These results suggest that in response to siRNA-induced beta-actin deficiency HeLa cells inactivate cofilin by phosphorylation rather than down-regulate its protein expression level. This study also demonstrates that the combination of RNA interference and 2-dimensional gel electrophoresis technologies provides a valuable method to study protein interactions in a specific cellular pathway. 相似文献
29.
Cattle grazing in CRP grasslands during the nesting season: effects on avian abundance and diversity
Benjamin S. Wilson William E. Jensen Gregory R. Houseman Mary Liz Jameson Molly M. Reichenborn D. Fraser Watson Alex R. Morphew Esben L. Kjaer 《The Journal of wildlife management》2022,86(2):e22188
The Conservation Reserve Program (CRP) is a primary tool for restoring grassland in the United States, in part as wildlife habitat, which has benefited declining grassland bird populations. Among potential mid-contract management practices used to maintain early-successional CRP grasslands, cattle grazing had been prohibited and is currently disincentivized during the primary nesting season for birds (much of the growing season), despite the important role that large herbivores historically played in structuring grassland ecosystems. Conservative grazing of CRP grasslands could increase spatial heterogeneity in vegetation structure and plant diversity, potentially supporting higher densities of some grassland bird species and higher bird diversity. Our objective was to determine the effect of experimental cattle grazing on species-specific relative abundance and occupancy, species diversity, and community dissimilarity of grassland birds on CRP grasslands across the longitudinal extent of Kansas, USA (a 63.5-cm precipitation gradient) during the 2017–2019 avian breeding seasons. Fifty-three of 108 fields were grazed by cattle during the growing seasons of 2017 and 2018 and all fields were rested from grazing in 2019. For all analyses, we examined separate model sets for semiarid western versus more mesic eastern Kansas. Using data from line transect surveys, we modeled relative abundances of 5 songbird species: grasshopper sparrow (Ammodramus savannarum), dickcissel (Spiza americana), eastern meadowlark (Sturnella magna), western meadowlark (Sturnella neglecta), and brown-headed cowbird (Molothrus ater). Grazing had delayed yet positive effects on abundances of grasshopper sparrow in western Kansas, and eastern meadowlark in eastern Kansas, but negative effects on dickcissel abundance in western Kansas and especially on burned fields in eastern Kansas. Somewhat counterintuitively, brown-headed cowbirds in western Kansas were more abundant on ungrazed versus grazed fields in the years after grazing began. In addition, we modeled multi-season occupancy of 3 gamebird species (ring-necked pheasant [Phasianus colcicus], northern bobwhite [Colinus virginianus], mourning dove [Zenaida macroura]) and Henslow's sparrow (Centronyx henslowii); grazing did not affect occupancy of these species. In eastern Kansas, species diversity was highest in grazed, unburned fields. In western Kansas, bird communities in grazed and ungrazed fields were dissimilar, as determined from multivariate analysis. Though regionally variable, conservative stocking of cattle on CRP grasslands during the nesting season as a mid-contract management tool might increase bird species diversity by restructuring habitat that accommodates a greater variety of species and decreasing abundances of species associated with taller, denser stands of vegetation. 相似文献
30.
Beck CR McKenzie BC Hashim AB Harris RC Zanuzdana A Agboado G Orton E Béchard-Evans L Morgan G Stevenson C Weston R Mukaigawara M Enstone J Augustine G Butt M Kim S Puleston R Dabke G Howard R O'Boyle J O'Brien M Ahyow L Denness H Farmer S Figureroa J Fisher P Greaves F Haroon M Haroon S Hird C Isba R Ishola DA Kerac M Parish V Roberts J Rosser J Theaker S Wallace D Wigglesworth N Lingard L Vinogradova Y Horiuchi H Peñalver J Nguyen-Van-Tam JS 《PloS one》2011,6(12):e29249