scholarly journals Survey of water proton longitudinal relaxation in liver in vivo

2021 ◽  
Author(s):  
John Charles Waterton
Keyword(s):  
Normal Liver ◽  
Population Variation ◽  
Water Proton ◽  
Proton Relaxation ◽  
Literature Searching ◽  
Repeatability Error ◽  
Coefficients Of Variation ◽  
Weighted Means ◽  
Propagation Of Errors

Abstract Objective To determine the variability, and preferred values, for normal liver longitudinal water proton relaxation rate R1 in the published literature. Methods Values of mean R1 and between-subject variance were obtained from literature searching. Weighted means were fitted to a heuristic and to a model. Results After exclusions, 116 publications (143 studies) remained, representing apparently normal liver in 3392 humans, 99 mice and 249 rats. Seventeen field strengths were included between 0.04 T and 9.4 T. Older studies tended to report higher between-subject coefficients of variation (CoV), but for studies published since 1992, the median between-subject CoV was 7.4%, and in half of those studies, measured R1 deviated from model by 8.0% or less. Discussion The within-study between-subject CoV incorporates repeatability error and true between-subject variation. Between-study variation also incorporates between-population variation, together with bias from interactions between methodology and physiology. While quantitative relaxometry ultimately requires validation with phantoms and analysis of propagation of errors, this survey allows investigators to compare their own R1 and variability values with the range of existing literature.

scholarly journals A Phantom System Designed to Assess the Effects of Membrane Lipids on Water Proton Relaxation

2018 ◽  
Author(s):  
Oshrat Shtangel ◽  
Aviv A. Mezer
Keyword(s):  
Membrane Lipids ◽  
Magnetization Transfer ◽  
Membrane Lipid ◽  
Water Proton ◽  
Proton Relaxation ◽  
Proton Density ◽  
Brain Lipids ◽  
Water Fraction ◽  
Lipid Environment

AbstractPurposeQuantitative magnetic resonance imaging (qMRI) provides a method for the non-invasive study of brain structure and associated changes, expressed in physical units. qMRI parameters have been shown to reflect brain tissue composition such as myelin. Nevertheless, it remains a major challenge to identify and quantify the contributions of specific molecular components to the MRI signal. Here, we describe a phantom system that can be used to evaluate the contribution of human brain lipids to qMRI parameters.MethodsA thin layer evaporation-hydration technique was used to formulate liposomes that mimic the physiological bi-layered membrane lipid environment. We then applied quantitative clinical MRI techniques with adjusted bias corrections in order to test the ability of the phantom system to estimate multiple qMRI parameters such as proton density (PD), T1, T2, T2* and magnetization transfer (MT).ResultsThe results indicated that phantoms composed of various lipids could provide a stable and reliable estimation of qMRI parameters. In addition, the calculated water fraction (WF) maps for the phantoms were found to accurately represent the true WF volumes.ConclusionWe have successfully created a biologically relevant liposome phantom system whose lipid composition can be fully controlled. This system can be used to measure the contributions of lipids to qMRI parameters under conditions that are relevant to in-vivo human scans.

Knockout of Ajuba Attenuates the Growth and Migration of Hepatocellular Carcinoma Cells

2020 ◽  
Vol 160 (11-12) ◽  
pp. 650-658
Author(s):  
Yichen Le ◽  
Yi He ◽  
Meirong Bai ◽  
Ying Wang ◽  
Jiaxue Wu ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Cell Growth ◽  
Cancer Progression ◽  
Normal Liver ◽  
Cell Growth And Migration ◽  
And Migration ◽  
Hcc Cells

Ajuba has been found to be mutated or aberrantly regulated in several human cancers and plays important roles in cancer progression via different signaling pathways. However, little is known about the role of Ajuba in hepatocellular carcinoma (HCC). Here, we found an upregulation of Ajuba expression in HCC tissues compared with normal liver tissues, while a poor prognosis was observed in HCC patients with high Ajuba expression. Knockout of Ajuba in HCC cells inhibited cell growth in vitro and in vivo, suppressed cell migration, and enhanced the cell apoptosis under stress. Moreover, re-expression of Ajuba in Ajuba-deficient cells could restore the phenotype of Ajuba-deficient cells. In conclusion, these results indicate that Ajuba is upregulated in HCC and promotes cell growth and migration of HCC cells, suggesting that Ajuba could possibly be a new target for HCC diagnosis and treatment.

scholarly journals In vivo tumour imaging employing regional delivery of novel gallium radiolabelled polymer composites

2021 ◽  
Vol 25 (1) ◽  
Author(s):  
Ross W. Stephens ◽  
Gregory D. Tredwell ◽  
Jessica L. Bell ◽  
Karen J. Knox ◽  
Lee A. Philip ◽  
...  
Keyword(s):  
Normal Liver ◽  
Ct Imaging ◽  
Liver Imaging ◽  
Polymer Microspheres ◽  
Tumour Imaging ◽  
Planar Imaging ◽  
Rabbit Lung ◽  
Vitro Binding

Abstract Background Understanding the regional vascular delivery of particles to tumour sites is a prerequisite for developing new diagnostic and therapeutic composites for treatment of oncology patients. We describe a novel imageable 67Ga-radiolabelled polymer composite that is biocompatible in an animal tumour model and can be used for preclinical imaging investigations of the transit of different sized particles through arterial networks of normal and tumour-bearing organs. Results Radiolabelling of polymer microspheres with 67Ga was achieved using a simple mix and wash method, with tannic acid as an immobilising agent. Final in vitro binding yields after autoclaving averaged 94.7%. In vivo stability of the composite was demonstrated in New Zealand white rabbits by intravenous administration, and intrahepatic artery instillations were made in normal and VX2 tumour implanted rabbit livers. Stability of radiolabel was sufficient for rabbit lung and liver imaging over at least 3 hours and 1 hour respectively, with lung retention of radiolabel over 91%, and retention in both normal and VX2 implanted livers of over 95%. SPECT-CT imaging of anaesthetised animals and planar imaging of excised livers showed visible accumulation of radiolabel in tumours. Importantly, microsphere administration and complete liver dispersal was more easily achieved with 8 μm diameter MS than with 30 μm MS, and the smaller microspheres provided more distinct and localised tumour imaging. Conclusion This method of producing 67Ga-radiolabelled polymer microspheres is suitable for SPECT-CT imaging of the regional vascular delivery of microspheres to tumour sites in animal models. Sharper distinction of model tumours from normal liver was obtained with smaller MS, and tumour resolution may be further improved by the use of 68Ga instead of 67Ga, to enable PET imaging.

Inspecting Insulin Products Using Water Proton NMR. I. Noninvasive vs Invasive Inspection

2021 ◽  
pp. 193229682110238
Author(s):  
Marc B. Taraban ◽  
Yilin Wang ◽  
Katharine T. Briggs ◽  
Yihua Bruce Yu
Keyword(s):  
Quality Control ◽  
Relaxation Rate ◽  
Drug Product ◽  
Proton Nmr ◽  
Water Proton ◽  
Proton Relaxation ◽  
Content Uniformity ◽  
Biologic Drugs ◽  
Insulin Solution ◽  
Insulin Pens

Background: There is a clear need to transition from batch-level to vial/syringe/pen-level quality control of biologic drugs, such as insulin. This could be achieved only by noninvasive and quantitative inspection technologies that maintain the integrity of the drug product. Methods: Four insulin products for patient self-injection presented as prefilled pens have been noninvasively and quantitatively inspected using the water proton NMR technology. The inspection output is the water proton relaxation rate R2(1H2O), a continuous numerical variable rather than binary pass/fail. Results: Ten pens of each product were inspected. R2(1H2O) displays insignificant variation among the 10 pens of each product, suggesting good insulin content uniformity in the inspected pens. It is also shown that transferring the insulin solution out of and then back into the insulin pen caused significant change in R2(1H2O), presumably due to exposure to O2 in air. Conclusions: Water proton NMR can noninvasively and quantitatively inspect insulin pens. wNMR can confirm product content uniformity, but not absolute content. Its sensitivity to sample transferring provides a way to detect drug product tampering. This opens the possibility of inspecting every pen/vial/syringe by manufacturers and end-users.

scholarly journals A SPECIFIC POISON IN THE LIVER EXTRACTS OF RABBITS INOCULATED WITH TYPHOID AND PRODIGIOSUS BACILLI INTRAVENOUSLY

1918 ◽  
Vol 28 (5) ◽  
pp. 571-583
Author(s):  
Julia T. Parker
Keyword(s):  
Anaphylactic Shock ◽  
Liver Extract ◽  
Lethal Dose ◽  
Toxic Substance ◽  
Normal Liver ◽  
Immune Serum ◽  
Minimum Lethal Dose ◽  
Lethal Doses

1. The livers of rabbits inoculated with cultures of Bacillus typhosus or Bacillus prodigiosus under certain conditions contain a toxic substance extractable with salt solution. When the toxic extracts are injected intravenously into normal rabbits the latter animals develop symptoms resembling those of anaphylactic shock and succumb. The lethal doses of the toxic extracts are far smaller than those of normal liver extract. 2. The livers of rabbits injected with typhoid antigen also yield a toxic extract. 3. Boiling as well as filtration through a Berkefeld filter only partially detoxicates the extract. 4. Tolerance to one to two lethal doses of the poisonous extracts can be induced by cautious immunization. 5. Rabbits actively immunized to Bacillus typhosus or Bacillus prodigiosus usually resist one lethal dose of the homologous liver poison; and animals tolerant to the typhoid liver poison resist one minimum lethal dose at least of Bacillus typhosus. 6. Typhoid immune serum is not detoxicating either in vivo or in vitro for the typhoid liver poison. 7. The liver poisons are specific, since rabbits actively immunized to either Bacillus typhosus or Bacillus prodigiosus withstand at least one minimum lethal dose of the homologous but not of the heterologous-liver poisons.

scholarly journals Long non-coding RNA LINC00641 promotes the growth and invasiveness of hepatocellular carcinoma by antagonizing miR-501-3p

2021 ◽  
Author(s):  
Haitao Xie ◽  
Hui Zhou ◽  
Yan Jiang ◽  
Wenqian Xu ◽  
Leping Zeng ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Normal Liver ◽  
In Vivo Studies ◽  
Luciferase Reporter ◽  
Normal Tissues ◽  
Non Coding Rna ◽  
Long Non Coding Rna ◽  
Proliferation And Invasion ◽  
Hcc Cells

IntroductionLong non-coding RNA LINC00641 has been reported to regulate tumor progression in several cancers. However, the expression and function of LINC00641 in hepatocellular carcinoma (HCC) is still unclear.Material and methodsIn this study, we measured the expression of LINC00641 in 79 pairs of HCC and adjacent normal liver tissues. The clinical significance of LINC00641 in HCC was explored. We also investigated the function of LINC00641 in HCC proliferation and invasion.ResultsWe observed that LINC00641 expression was significantly increased in HCC relative to normal tissues (P < 0.0001). High expression of LINC00641 was significantly associated with vascular invasion, advanced TNM stage, and reduced overall survival in HCC patients. Knockdown of LINC00641 inhibited the proliferation, colony formation, and invasion of HCC cells. In contrast, overexpression of LINC00641 promoted HCC cell growth and invasiveness. In vivo studies confirmed that knockdown of LINC00641 restrained tumorigenesis of HCC cells. Mechanistic studies revealed that LINC00641 inhibited the expression of miR-501-3p, which has been previously reported to act as a tumor suppressor in HCC. Furthermore, luciferase reporter assays validated that LINC00641 harbored a target site for miR-501-3p. Rescue experiments demonstrated that LINC00641-induced proliferation and invasion of HCC cells was reversed by co-expression of miR-501-3p.ConclusionsTaken together, LINC00641 contributes to aggressive phenotype of HCC cells by sponging miR-501-3p and represents a promising therapeutic target for this disease.

Longitudinal Water Proton Relaxivity and In Vivo T1 MR Images of Mixed Zn(II)/Gd(III) Oxide Nanoparticles

2017 ◽  
Vol 17 (4) ◽  
pp. 2423-2430
Author(s):  
Tirusew Tegafaw ◽  
Bardul Alam Bony ◽  
Wenlong Xu ◽  
Hyunsil Cha ◽  
Yongmin Chang ◽  
...  
Keyword(s):  
Water Proton ◽  
Oxide Nanoparticles ◽  
Mr Images

Water-Proton Relaxation by a Noncovalent Albumin-Binding Gadolinium Chelate

2002 ◽  
Vol 9 (1) ◽  
pp. S11-S16 ◽  
Author(s):  
Kofi Adzamli ◽  
Marga Spiller ◽  
Seymour H. Koenig
Keyword(s):  
Water Proton ◽  
Proton Relaxation ◽  
Albumin Binding ◽  
Gadolinium Chelate

Steroid-induced cell proliferation in vivo is associated with increased c-myc proto-oncogene transcript abundance

Development ◽  
1988 ◽  
Vol 104 (1) ◽  
pp. 87-95
Author(s):  
S.A. Rempel ◽  
R.N. Johnston
Keyword(s):  
Cell Proliferation ◽  
Growth Factors ◽  
Steroid Hormones ◽  
Steroid Hormone ◽  
Normal Liver ◽  
Transcript Abundance ◽  
Chicken Oviduct ◽  
Massive Cell ◽  
In Cells

Enhanced c-myc transcript abundance has been observed in a variety of human malignancies, in normal liver tissue induced to proliferate in vivo by partial hepatectomy and in cells in culture induced to proliferate with the addition of protein hormones and growth factors. Little is known, however, about the expression of cellular proto-oncogenes in cells induced to proliferate in vivo by steroid hormones. Experiments reported here indicate that when cells of the immature chicken oviduct are induced to undergo rapid in vivo proliferation by application of the estrogen hormone 17 beta-estradiol, the onset of this proliferation is associated with a rapid, large, and transient increase in c-myc transcript abundance. When estrogen is administered to chickens in which the oviduct has already differentiated, neither massive cell proliferation nor large increases in c-myc transcript abundance are induced. We conclude that the abundance of c-myc transcripts in vivo correlates well with the degree of cell proliferation induced by steroid hormone.

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