LIVIVO - Search results -

Search results

Result 1 - 10 of total 14

Search options

Article ; Online: Control of poly(A)-tail length and translation in vertebrate oocytes and early embryos.

Xiang, Kehui / Ly, Jimmy / Bartel, David P

2024 Volume 59, Issue 8, Page(s) 1058–1074.e11

Abstract: During oocyte maturation and early embryogenesis, changes in mRNA poly(A)-tail lengths strongly influence translation, but how these tail-length changes are orchestrated has been unclear. Here, we performed tail-length and translational profiling of mRNA ...

Abstract	During oocyte maturation and early embryogenesis, changes in mRNA poly(A)-tail lengths strongly influence translation, but how these tail-length changes are orchestrated has been unclear. Here, we performed tail-length and translational profiling of mRNA reporter libraries (each with millions of 3' UTR sequence variants) in frog oocytes and embryos and in fish embryos. Contrasting to previously proposed cytoplasmic polyadenylation elements (CPEs), we found that a shorter element, UUUUA, together with the polyadenylation signal (PAS), specify cytoplasmic polyadenylation, and we identified contextual features that modulate the activity of both elements. In maturing oocytes, this tail lengthening occurs against a backdrop of global deadenylation and the action of C-rich elements that specify tail-length-independent translational repression. In embryos, cytoplasmic polyadenylation becomes more permissive, and additional elements specify waves of stage-specific deadenylation. Together, these findings largely explain the complex tapestry of tail-length changes observed in early frog and fish development, with strong evidence of conservation in both mice and humans.
MeSH term(s)	Animals ; Oocytes/metabolism ; Oocytes/cytology ; Polyadenylation ; Protein Biosynthesis ; Poly A/metabolism ; Poly A/genetics ; 3' Untranslated Regions/genetics ; RNA, Messenger/genetics ; RNA, Messenger/metabolism ; Gene Expression Regulation, Developmental ; Mice ; Humans ; Embryo, Nonmammalian/metabolism ; Embryonic Development/genetics ; Female ; Xenopus laevis/metabolism ; Xenopus laevis/embryology ; Xenopus laevis/genetics ; Cytoplasm/metabolism
Chemical Substances	Poly A (24937-83-5) ; 3' Untranslated Regions ; RNA, Messenger
Language	English
Publishing date	2024-03-08
Publishing country	United States
Document type	Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, N.I.H., Extramural
ZDB-ID	2054967-2
ISSN	1878-1551 ; 1534-5807
ISSN (online)	1878-1551
ISSN	1534-5807
DOI	10.1016/j.devcel.2024.02.007
Database	MEDical Literature Analysis and Retrieval System OnLINE

Full text online

Accessible to users with ZB MED library card

In stock of ZB MED Cologne/Königswinter

Zs.A 5742: Show issues			Location: Je nach Verfügbarkeit (siehe Angabe bei Bestand) bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular Jg. 1995 - 2021: Lesesall (2.OG) ab Jg. 2022: Lesesaal (EG)
Zs.MG 76: Show issues

Order via subito

This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

Details ▾

Article: A conserved germline-specific Dsn1 alternative splice isoform supports oocyte and embryo development.

Ly, Jimmy / Blengini, Cecilia S / Cady, Sarah L / Schindler, Karen / Cheeseman, Iain M

bioRxiv : the preprint server for biology

2024

Abstract: Alternative mRNA splicing can generate distinct protein isoforms to allow for the differential control of cell processes across cell types. However, alternative splice isoforms that differentially modulate distinct cell division programs have remained ... ...

Abstract	Alternative mRNA splicing can generate distinct protein isoforms to allow for the differential control of cell processes across cell types. However, alternative splice isoforms that differentially modulate distinct cell division programs have remained elusive. Here, we demonstrate that mammalian germ cells express an alternate mRNA splice isoform for the kinetochore component, DSN1, a subunit of the MIS12 complex that links the centromeres to spindle microtubules during chromosome segregation. This germline DSN1 isoform bypasses the requirement for Aurora kinase phosphorylation for its centromere localization due to the absence of a key regulatory region allowing DSN1 to display persistent centromere localization. Expression of the germline DSN1 isoform in somatic cells results in constitutive kinetochore localization, chromosome segregation errors, and growth defects, providing an explanation for its tight cell type-specific expression. Reciprocally, precisely eliminating expression of the germline DSN1 splice isoform in mouse models disrupts oocyte maturation and early embryonic divisions coupled with a reduction in fertility. Together, this work identifies a germline-specific splice isoform for a chromosome segregation component and implicates its role in mammalian fertility.
Language	English
Publishing date	2024-04-18
Publishing country	United States
Document type	Preprint
DOI	10.1101/2024.04.17.589883
Database	MEDical Literature Analysis and Retrieval System OnLINE

Inter-library loan at ZB MED

Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

Details ▾

Article: Nuclear release of eIF1 globally increases stringency of start-codon selection to preserve mitotic arrest physiology.

Ly, Jimmy / Xiang, Kehui / Su, Kuan-Chung / Sissoko, Gunter B / Bartel, David P / Cheeseman, Iain M

bioRxiv : the preprint server for biology

2024

Abstract: Regulated start-codon selection has the potential to reshape the proteome through the differential production of uORFs, canonical proteins, and alternative translational isoforms. However, conditions under which start-codon selection is altered remain ... ...

Abstract	Regulated start-codon selection has the potential to reshape the proteome through the differential production of uORFs, canonical proteins, and alternative translational isoforms. However, conditions under which start-codon selection is altered remain poorly defined. Here, using transcriptome-wide translation initiation site profiling, we reveal a global increase in the stringency of start-codon selection during mammalian mitosis. Low-efficiency initiation sites are preferentially repressed in mitosis, resulting in pervasive changes in the translation of thousands of start sites and their corresponding protein products. This increased stringency of start-codon selection during mitosis results from increased interactions between the key regulator of start-codon selection, eIF1, and the 40S ribosome. We find that increased eIF1-40S ribosome interactions during mitosis are mediated by the release of a nuclear pool of eIF1 upon nuclear envelope breakdown. Selectively depleting the nuclear pool of eIF1 eliminates the changes to translational stringency during mitosis, resulting in altered mitotic proteome composition. In addition, preventing mitotic translational rewiring results in substantially increased cell death and decreased mitotic slippage following treatment with anti-mitotic chemotherapeutics. Thus, cells globally control translation initiation stringency with critical roles during the mammalian cell cycle to preserve mitotic cell physiology.
Language	English
Publishing date	2024-04-06
Publishing country	United States
Document type	Preprint
DOI	10.1101/2024.04.06.588385
Database	MEDical Literature Analysis and Retrieval System OnLINE

Inter-library loan at ZB MED

Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

Details ▾

Article ; Online: The phenotypic landscape of essential human genes.

Funk, Luke / Su, Kuan-Chung / Ly, Jimmy / Feldman, David / Singh, Avtar / Moodie, Brittania / Blainey, Paul C / Cheeseman, Iain M

Cell

2022 Volume 185, Issue 24, Page(s) 4634–4653.e22

Abstract: Understanding the basis for cellular growth, proliferation, and function requires determining the roles of essential genes in diverse cellular processes, including visualizing their contributions to cellular organization and morphology. Here, we combined ...

Abstract	Understanding the basis for cellular growth, proliferation, and function requires determining the roles of essential genes in diverse cellular processes, including visualizing their contributions to cellular organization and morphology. Here, we combined pooled CRISPR-Cas9-based functional screening of 5,072 fitness-conferring genes in human HeLa cells with microscopy-based imaging of DNA, the DNA damage response, actin, and microtubules. Analysis of >31 million individual cells identified measurable phenotypes for >90% of gene knockouts, implicating gene targets in specific cellular processes. Clustering of phenotypic similarities based on hundreds of quantitative parameters further revealed co-functional genes across diverse cellular activities, providing predictions for gene functions and associations. By conducting pooled live-cell screening of ∼450,000 cell division events for 239 genes, we additionally identified diverse genes with functional contributions to chromosome segregation. Our work establishes a resource detailing the consequences of disrupting core cellular processes that represents the functional landscape of essential human genes.
MeSH term(s)	Humans ; CRISPR-Cas Systems ; Genes, Essential ; HeLa Cells ; Gene Knockout Techniques ; Phenotype
Language	English
Publishing date	2022-11-07
Publishing country	United States
Document type	Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, N.I.H., Extramural ; Research Support, U.S. Gov't, Non-P.H.S.
ZDB-ID	187009-9
ISSN	1097-4172 ; 0092-8674
ISSN (online)	1097-4172
ISSN	0092-8674
DOI	10.1016/j.cell.2022.10.017
Database	MEDical Literature Analysis and Retrieval System OnLINE

Full text online

Accessible to users with ZB MED library card

In stock of ZB MED Cologne/Königswinter

Zs.A 1167: Show issues			Location: Je nach Verfügbarkeit (siehe Angabe bei Bestand) bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular Jg. 1995 - 2021: Lesesall (1.OG) ab Jg. 2022: Lesesaal (EG)
Zs.MG 58: Show issues

Order via subito

Details ▾

Article ; Online: Role of 3 Tesla MR Neurography and CT-guided Injections for Pudendal Neuralgia: Analysis of Pain Response.

Ly, Jimmy / Scott, Kelly / Xi, Yin / Ashikyan, Oganes / Chhabra, Avneesh

Pain physician

2019 Volume 22, Issue 4, Page(s) E333–E344

Abstract: Background: Magnetic resonance neurography (MRN) has an increasing role in the diagnosis and management of pudendal neuralgia, a neurogenic cause of chronic pelvic pain.: Objective: The objective of this research was to determine the role of MRN in ... ...

Abstract	Background: Magnetic resonance neurography (MRN) has an increasing role in the diagnosis and management of pudendal neuralgia, a neurogenic cause of chronic pelvic pain. Objective: The objective of this research was to determine the role of MRN in predicting improved pain outcomes following computed tomography (CT)-guided perineural injections in patients with pudendal neuralgia. Study design: This study used a retrospective cross-sectional study design. Setting: The research was conducted at a large academic hospital. Methods: Patients: Ninety-one patients (139 injections) who received MRN and CT-guided pudendal blocks were analyzed. Intervention: A 3Tesla (T) scanner was used to evaluate the lumbosacral plexus for pudendal neuropathy. Prior to receiving a CT-guided pudendal perineural injection, patients were given pain logs and asked to record pain on a visual analog scale. Measurement: MRN findings for pudendal neuropathy were compared to the results of the CT-guided pudendal nerve blocks. Injection pain responses were categorized into 3 groups - positive block, possible positive block, and negative block.Statistical Tests: A chi-square test was used to test any association, and a Cochran-Armitage trend test was used to test any trend. Significance level was set at .05. All analyses were done in SAS Version 9.4 (SAS Institute, Inc., Cary, NC). Results: Ninety-one patients (139 injections) who received MRN were analyzed. Of these 139 injections, 41 were considered positive (29.5%), 52 of 139 were possible positives (37.4%), and 46 of 139 were negative blocks (33.1%). Of the patients who had a positive pudendal block, no significant difference was found between the MRN result and the pudendal perineural injection response (P = .57). Women had better overall response to pudendal blocks, but this response was not associated with MRN findings (P = .34). However, positive MRN results were associated with better pain response in men (P = .005). Patients who reported bowel dysfunction also had a better response to pudendal perineural injection (P = .02). Limitations: Some limitations include subjectivity of pain reporting, reporting consistency, absence of a control group, and the retrospective nature of the chart review. Conclusion: Pudendal perineural injections improve pain in patients with pudendal neuralgia and positive MRN results are associated with better response in men. Key words: MRI, MRN, CT injection, pudendal neuralgia, pudendal nerve, pelvic pain, chronic pelvic pain, pudendal neuropathy.
MeSH term(s)	Adult ; Aged ; Aged, 80 and over ; Anesthetics, Local/administration & dosage ; Cross-Sectional Studies ; Female ; Humans ; Magnetic Resonance Imaging/methods ; Male ; Middle Aged ; Nerve Block/methods ; Pelvic Pain/drug therapy ; Pelvic Pain/etiology ; Pudendal Nerve/diagnostic imaging ; Pudendal Nerve/drug effects ; Pudendal Neuralgia/diagnosis ; Pudendal Neuralgia/drug therapy ; Radiography, Interventional/methods ; Retrospective Studies ; Tomography, X-Ray Computed/methods
Chemical Substances	Anesthetics, Local
Language	English
Publishing date	2019-07-13
Publishing country	United States
Document type	Journal Article
ZDB-ID	2146393-1
ISSN	2150-1149 ; 1533-3159
ISSN (online)	2150-1149
ISSN	1533-3159
Database	MEDical Literature Analysis and Retrieval System OnLINE

In stock of ZB MED Cologne/Königswinter

Zs.A 5930: Show issues

Location:
Je nach Verfügbarkeit (siehe Angabe bei Bestand)
bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular
Jg. 1995 - 2021: Lesesall (2.OG)
ab Jg. 2022: Lesesaal (EG)

Order via subito

Details ▾
- See ZB MED holdings
- Order with fees

Article ; Online: Toward miniaturized analysis of chemical identity and purity of radiopharmaceuticals via microchip electrophoresis.

Ly, Jimmy / Ha, Noel S / Cheung, Shilin / van Dam, R Michael

Analytical and bioanalytical chemistry

2018 Volume 410, Issue 9, Page(s) 2423–2436

Abstract: Miniaturized synthesis of positron emission tomography (PET) tracers is poised to offer numerous advantages including reduced tracer production costs and increased availability of diverse tracers. While many steps of the tracer production process have ... ...

Abstract	Miniaturized synthesis of positron emission tomography (PET) tracers is poised to offer numerous advantages including reduced tracer production costs and increased availability of diverse tracers. While many steps of the tracer production process have been miniaturized, there has been relatively little development of microscale systems for the quality control (QC) testing process that is required by regulatory agencies to ensure purity, identity, and biological safety of the radiotracer before use in human subjects. Every batch must be tested, and in contrast with ordinary pharmaceuticals, the whole set of tests of radiopharmaceuticals must be completed within a short-period of time to minimize losses due to radioactive decay. By replacing conventional techniques with microscale analytical ones, it may be possible to significantly reduce instrument cost, conserve lab space, shorten analysis times, and streamline this aspect of PET tracer production. We focus in this work on miniaturizing the subset of QC tests for chemical identity and purity. These tests generally require high-resolution chromatographic separation prior to detection to enable the approach to be applied to many different tracers (and their impurities), and have not yet, to the best of our knowledge, been tackled in microfluidic systems. Toward this end, we previously explored the feasibility of using the technique of capillary electrophoresis (CE) as a replacement for the "gold standard" approach of using high-performance liquid chromatography (HPLC) since CE offers similar separating power, flexibility, and sensitivity, but can readily be implemented in a microchip format. Using a conventional CE system, we previously demonstrated the successful separation of non-radioactive version of a clinical PET tracer, 3'-deoxy-3'-fluorothymidine (FLT), from its known by-products, and the separation of the PET tracer 1-(2'-deoxy-2'-fluoro-β-D-arabinofuranosyl)-cytosine (D-FAC) from its α-isomer, with sensitivity nearly as good as HPLC. Building on this feasibility study, in this paper, we describe the first effort to miniaturize the chemical identity and purity tests by using microchip electrophoresis (MCE). The fully automated proof-of-concept system comprises a chip for sample injection, a separation capillary, and an optical detection chip. Using the same model compound (FLT and its known by-products), we demonstrate that samples can be injected, separated, and detected, and show the potential to match the performance of HPLC. Addition of a radiation detector in the future would enable analysis of radiochemical identity and purity in the same device. We envision that eventually this MCE method could be combined with other miniaturized QC tests into a compact integrated system for automated routine QC testing of radiopharmaceuticals in the future. Graphical abstract Miniaturized quality control (QC) testing of batches of radiopharmaceuticals via microfluidic analysis. The proof-of-concept hybrid microchip electrophoresis (MCE) device demonstrated the feasibility of achieving comparable performance to conventional analytical instruments (HPLC or CE) for chemical purity testing.
MeSH term(s)	Chromatography, High Pressure Liquid ; Electrophoresis, Microchip/instrumentation ; Electrophoresis, Microchip/methods ; Equipment Design ; Quality Control ; Radiopharmaceuticals/analysis
Chemical Substances	Radiopharmaceuticals
Language	English
Publishing date	2018-02-22
Publishing country	Germany
Document type	Journal Article
ZDB-ID	201093-8
ISSN	1618-2650 ; 0016-1152 ; 0372-7920
ISSN (online)	1618-2650
ISSN	0016-1152 ; 0372-7920
DOI	10.1007/s00216-018-0924-y
Database	MEDical Literature Analysis and Retrieval System OnLINE

Full text online

Accessible to users with ZB MED library card

In stock of ZB MED Bonn / Germany

Z 4' 69/97: Show issues
Archiv 3: Show issues
Z 9.4: Show issues

Order via subito

Inter-library loan at ZB MED

Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

Details ▾

Article: Toward miniaturized analysis of chemical identity and purity of radiopharmaceuticals via microchip electrophoresis

Ly, Jimmy / Ha, NoelS / Cheung, Shilin / van Dam, R.Michael

Analytical and bioanalytical chemistry. 2018 Mar., v. 410, no. 9

2018

Abstract	Miniaturized synthesis of positron emission tomography (PET) tracers is poised to offer numerous advantages including reduced tracer production costs and increased availability of diverse tracers. While many steps of the tracer production process have been miniaturized, there has been relatively little development of microscale systems for the quality control (QC) testing process that is required by regulatory agencies to ensure purity, identity, and biological safety of the radiotracer before use in human subjects. Every batch must be tested, and in contrast with ordinary pharmaceuticals, the whole set of tests of radiopharmaceuticals must be completed within a short-period of time to minimize losses due to radioactive decay. By replacing conventional techniques with microscale analytical ones, it may be possible to significantly reduce instrument cost, conserve lab space, shorten analysis times, and streamline this aspect of PET tracer production. We focus in this work on miniaturizing the subset of QC tests for chemical identity and purity. These tests generally require high-resolution chromatographic separation prior to detection to enable the approach to be applied to many different tracers (and their impurities), and have not yet, to the best of our knowledge, been tackled in microfluidic systems. Toward this end, we previously explored the feasibility of using the technique of capillary electrophoresis (CE) as a replacement for the “gold standard” approach of using high-performance liquid chromatography (HPLC) since CE offers similar separating power, flexibility, and sensitivity, but can readily be implemented in a microchip format. Using a conventional CE system, we previously demonstrated the successful separation of non-radioactive version of a clinical PET tracer, 3′-deoxy-3′-fluorothymidine (FLT), from its known by-products, and the separation of the PET tracer 1-(2′-deoxy-2′-fluoro-β-D-arabinofuranosyl)-cytosine (D-FAC) from its α-isomer, with sensitivity nearly as good as HPLC. Building on this feasibility study, in this paper, we describe the first effort to miniaturize the chemical identity and purity tests by using microchip electrophoresis (MCE). The fully automated proof-of-concept system comprises a chip for sample injection, a separation capillary, and an optical detection chip. Using the same model compound (FLT and its known by-products), we demonstrate that samples can be injected, separated, and detected, and show the potential to match the performance of HPLC. Addition of a radiation detector in the future would enable analysis of radiochemical identity and purity in the same device. We envision that eventually this MCE method could be combined with other miniaturized QC tests into a compact integrated system for automated routine QC testing of radiopharmaceuticals in the future. Graphical abstract Miniaturized quality control (QC) testing of batches of radiopharmaceuticals via microfluidic analysis. The proof-of-concept hybrid microchip electrophoresis (MCE) device demonstrated the feasibility of achieving comparable performance to conventional analytical instruments (HPLC or CE) for chemical purity testing.
Keywords	byproducts ; capillary electrophoresis ; drugs ; feasibility studies ; high performance liquid chromatography ; models ; positron-emission tomography ; production costs ; quality control ; tracer techniques
Language	English
Dates of publication	2018-03
Size	p. 2423-2436.
Publishing place	Springer Berlin Heidelberg
Document type	Article
ISSN	1618-2642
DOI	10.1007/s00216-018-0924-y
Database	NAL-Catalogue (AGRICOLA)

Full text online

Accessible to users with ZB MED library card

Order via subito

Inter-library loan at ZB MED

Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

Details ▾
- Full text online
- Order with fees

Article ; Online: Renal Embolization-Induced Uremic Swine Model for Assessment of Next-Generation Implantable Hemodialyzers.

Moyer, Jarrett / Wilson, Mark W / Sorrentino, Thomas A / Santandreu, Ana / Chen, Caressa / Hu, Dean / Kerdok, Amy / Porock, Edward / Wright, Nathan / Ly, Jimmy / Blaha, Charles / Frassetto, Lynda A / Fissell, William H / Vartanian, Shant M / Roy, Shuvo

Toxins

2023 Volume 15, Issue 9

Abstract: Reliable models of renal failure in large animals are critical to the successful translation of the next generation of renal replacement therapies (RRT) into humans. While models exist for the induction of renal failure, none are optimized for the ... ...

Abstract	Reliable models of renal failure in large animals are critical to the successful translation of the next generation of renal replacement therapies (RRT) into humans. While models exist for the induction of renal failure, none are optimized for the implantation of devices to the retroperitoneal vasculature. We successfully piloted an embolization-to-implantation protocol enabling the first implant of a silicon nanopore membrane hemodialyzer (SNMHD) in a swine renal failure model. Renal arterial embolization is a non-invasive approach to near-total nephrectomy that preserves retroperitoneal anatomy for device implants. Silicon nanopore membranes (SNM) are efficient blood-compatible membranes that enable novel approaches to RRT. Yucatan minipigs underwent staged bilateral renal arterial embolization to induce renal failure, managed by intermittent hemodialysis. A small-scale arteriovenous SNMHD prototype was implanted into the retroperitoneum. Dialysate catheters were tunneled externally for connection to a dialysate recirculation pump. SNMHD clearance was determined by intermittent sampling of recirculating dialysate. Creatinine and urea clearance through the SNMHD were 76-105 mL/min/m
MeSH term(s)	Humans ; Swine ; Animals ; Kidneys, Artificial ; Creatinine ; Pilot Projects ; Silicon ; Swine, Miniature ; Renal Insufficiency ; Dialysis Solutions ; Urea
Chemical Substances	Creatinine (AYI8EX34EU) ; Silicon (Z4152N8IUI) ; Dialysis Solutions ; Urea (8W8T17847W)
Language	English
Publishing date	2023-09-04
Publishing country	Switzerland
Document type	Journal Article ; Research Support, N.I.H., Extramural
ZDB-ID	2518395-3
ISSN	2072-6651 ; 2072-6651
ISSN (online)	2072-6651
ISSN	2072-6651
DOI	10.3390/toxins15090547
Database	MEDical Literature Analysis and Retrieval System OnLINE

Order via subito

Article ; Online: Alpha-satellite RNA transcripts are repressed by centromere-nucleolus associations.

Bury, Leah / Moodie, Brittania / Ly, Jimmy / McKay, Liliana S / Miga, Karen Hh / Cheeseman, Iain M

eLife

2020 Volume 9

Abstract: Although originally thought to be silent chromosomal regions, centromeres are instead actively transcribed. However, the behavior and contributions of centromere-derived RNAs have remained unclear. Here, we used single-molecule fluorescence in-situ ... ...

Abstract	Although originally thought to be silent chromosomal regions, centromeres are instead actively transcribed. However, the behavior and contributions of centromere-derived RNAs have remained unclear. Here, we used single-molecule fluorescence in-situ hybridization (smFISH) to detect alpha-satellite RNA transcripts in intact human cells. We find that alpha-satellite RNA-smFISH foci levels vary across cell lines and over the cell cycle, but do not remain associated with centromeres, displaying localization consistent with other long non-coding RNAs. Alpha-satellite expression occurs through RNA polymerase II-dependent transcription, but does not require established centromere or cell division components. Instead, our work implicates centromere-nucleolar interactions as repressing alpha-satellite expression. The fraction of nucleolar-localized centromeres inversely correlates with alpha-satellite transcripts levels across cell lines and transcript levels increase substantially when the nucleolus is disrupted. The control of alpha-satellite transcripts by centromere-nucleolar contacts provides a mechanism to modulate centromere transcription and chromatin dynamics across diverse cell states and conditions.
MeSH term(s)	Cell Line ; Cell Nucleolus/genetics ; Cell Nucleolus/metabolism ; Centromere/genetics ; Centromere/metabolism ; Chromatin/genetics ; Chromatin/metabolism ; Humans ; RNA Polymerase II/genetics ; RNA Polymerase II/metabolism ; RNA, Long Noncoding/genetics ; RNA, Long Noncoding/metabolism ; RNA, Satellite/genetics ; RNA, Satellite/metabolism ; Transcription, Genetic
Chemical Substances	Chromatin ; RNA, Long Noncoding ; RNA, Satellite ; RNA Polymerase II (EC 2.7.7.-)
Language	English
Publishing date	2020-11-11
Publishing country	England
Document type	Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
ZDB-ID	2687154-3
ISSN	2050-084X ; 2050-084X
ISSN (online)	2050-084X
ISSN	2050-084X
DOI	10.7554/eLife.59770
Database	MEDical Literature Analysis and Retrieval System OnLINE

Order via subito

Article ; Online: Novel volumetric method for highly repeatable injection in microchip electrophoresis.

Ha, Noel S / Ly, Jimmy / Jones, Jason / Cheung, Shilin / van Dam, R Michael

Analytica chimica acta

2017 Volume 985, Page(s) 129–140

Abstract: A novel injector for microchip electrophoresis (MCE) has been designed and evaluated that achieves very high repeatability of injection volume suitable for quantitative analysis. It eliminates the injection biases in electrokinetic injection and the ... ...

Abstract	A novel injector for microchip electrophoresis (MCE) has been designed and evaluated that achieves very high repeatability of injection volume suitable for quantitative analysis. It eliminates the injection biases in electrokinetic injection and the dependence on pressure and sample properties in hydrodynamic injection. The microfluidic injector, made of poly(dimethylsiloxane) (PDMS), operates similarly to an HPLC injection valve. It contains a channel segment (chamber) with a well-defined volume that serves as an "injection loop". Using on-chip microvalves, the chamber can be connected to the sample source during the "loading" step, and to the CE separation channel during the "injection" step. Once the valves are opened in the second state, electrophoretic potential is applied to separate the sample. For evaluation and demonstration purposes, the microinjector was connected to a 75 μm ID capillary and UV absorbance detector. For single compounds, a relative standard deviation (RSD) of peak area as low as 1.04% (n = 11) was obtained, and for compound mixtures, RSD as low as 0.40% (n = 4) was observed. Using the same microchip, the performance of this new injection technique was compared to hydrodynamic injection and found to have improved repeatability and less dependence on sample viscosity. Furthermore, a non-radioactive version of the positron-emission tomography (PET) imaging probe, FLT, was successfully separated from its known 3 structurally-similar byproducts with baseline resolution, demonstrating the potential for rapid, quantitative analysis of impurities to ensure the safety of batches of short-lived radiotracers. Both the separation efficiency and injection repeatability were found to be substantially higher when using the novel volumetric injection approach compared to electrokinetic injection (performed in the same chip). This novel microinjector provides a straightforward way to improve the performance of hydrodynamic injection and enables extremely repeatable sample volume injection in MCE. It could be used in any MCE application where volume repeatability is needed, including the quantitation of impurities in pharmaceutical or radiopharmaceutical samples.
Language	English
Publishing date	2017-06-19
Publishing country	Netherlands
Document type	Journal Article
ZDB-ID	1483436-4
ISSN	1873-4324 ; 0003-2670
ISSN (online)	1873-4324
ISSN	0003-2670
DOI	10.1016/j.aca.2017.05.037
Database	MEDical Literature Analysis and Retrieval System OnLINE

Full text online

Accessible to users with ZB MED library card

Order via subito

Details ▾
- Full text online
- Order with fees

To top

Full text online

More links

Kategorien

In stock of ZB MED Cologne/Königswinter

Order via subito

More links

Kategorien

Inter-library loan at ZB MED

More links

Kategorien

Inter-library loan at ZB MED

Full text online

More links

Kategorien

In stock of ZB MED Cologne/Königswinter

Order via subito

More links

Kategorien

In stock of ZB MED Cologne/Königswinter

Order via subito

Full text online

More links

Kategorien

In stock of ZB MED Bonn / Germany

Order via subito

Inter-library loan at ZB MED

Full text online

More links

Kategorien

Order via subito

Inter-library loan at ZB MED

More links

Kategorien

Order via subito

More links

Kategorien

Order via subito

Full text online

More links

Kategorien

Order via subito