Rapid simultaneous acquisition of macromolecular tissue volume, susceptibility, and relaxometry maps

Accurate and consistent measurement of tissue volume is critical to performing many types of islet research; however, conventional visual determination of isolated islet yields through a microscope is heavily operator dependent. An improved method of islet volume determination using digital image analysis (DIA) was developed to remove operator bias and automate the islet counting process. A series of 140 porcine islet isolations were used to evaluate the DIA method in three separate stages. In Stage 1 ( n = 29 isolations), the conventional and DIA methods were correlated with two other independent islet quantitation methods: insulin extraction, and DNA extraction. It was found that volumes determined by DIA correlated more closely with insulin content and DNA content than did conventionally determined volumes. In Stages 2 and 3 ( n = 54 and 57 isolations, respectively), it was shown that an increase in the number of fields analyzed by DIA did not significantly improve the quality of the correlations. Inclusion of very small tissue (<50 fun in diameter), which is ignored in the conventional protocol affected yields by less than 10% and did not significantly improve the correlation with insulin or DNA content. Quantitation of isolated islet tissue volume using DIA has been shown to be rapid, consistent, and objective. In the laboratory, use of this method as the standard for islet volume measurement will allow more meaningful comparison of experimental results between centers. In the clinic, its use will allow more accurate dosing of transplanted tissue. © 1998 Elsevier Science Inc.

Download Full-text

Measurement of synovial tissue volume in knee osteoarthritis using a semiautomated MRI‐based quantitative approach

Magnetic Resonance in Medicine ◽

10.1002/mrm.27633 ◽

2019 ◽

Vol 81 (5) ◽

pp. 3056-3064 ◽

Cited By ~ 4

Author(s):

Thomas A. Perry ◽

Andrew Gait ◽

Terence W. O’Neill ◽

Matthew J. Parkes ◽

Richard Hodgson ◽

...

Keyword(s):

Knee Osteoarthritis ◽

Synovial Tissue ◽

Quantitative Approach ◽

Tissue Volume

Download Full-text

Brain tissue volume estimation to detect Alzheimer’s disease in magnetic resonance images

Soft Computing ◽

10.1007/s00500-021-05621-8 ◽

2021 ◽

Author(s):

T. Priya ◽

P. Kalavathi ◽

V. B. Surya Prasath ◽

R. Sivanesan

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Magnetic Resonance ◽

Brain Tissue ◽

Magnetic Resonance Images ◽

Volume Estimation ◽

Tissue Volume

Download Full-text

Safety and efficacy of low-dose PI3K inhibitor taselisib in adult patients with CLOVES and Klippel–Trenaunay syndrome (KTS): the TOTEM trial, a phase 1/2 multicenter, open-label, single-arm study

Genetics in Medicine ◽

10.1038/s41436-021-01290-y ◽

2021 ◽

Author(s):

M. Luu ◽

P. Vabres ◽

H. Devilliers ◽

R. Loffroy ◽

A. Phan ◽

...

Keyword(s):

Low Dose ◽

Phase 1 ◽

Pi3k Inhibitor ◽

Functional Improvement ◽

Open Label ◽

Tissue Volume ◽

Pathogenic Variants ◽

Patient Reported ◽

Affected Tissue ◽

Phosphoinositide 3 Kinase

ABSTRACT Purpose PIK3CA pathogenic variants in the PIK3CA-related overgrowth spectrum (PROS) activate phosphoinositide 3-kinase signaling, providing a rationale for targeted therapy, but no drug has proven efficacy and safety in this population. Our aim was to establish the six-month tolerability and efficacy of low-dose taselisib, a selective class I PI3K inhibitor, in PROS patients. Methods Patients over 16 years with PROS and PIK3CA pathogenic variants were included in a phase IB/IIA multicenter, open-label single-arm trial (six patients at 1 mg/day of taselisib, then 24 at 2 mg/day). The primary outcome was the occurrence of dose limiting toxicity (DLT). Efficacy outcomes were the relative changes after treatment of (1) tissue volume at affected and unaffected sites, both clinically and on imaging; (2) cutaneous vascular outcomes when relevant; (3) biologic parameters; (4) quality of life; and (5) patient-reported outcomes. Results Among 19 enrolled patients, 2 experienced a DLT (enteritis and pachymeningitis) leading to early trial termination (17 treated, 10 completed the study). No serious adverse reaction occurred in the 1 mg cohort (n = 6). No significant reduction in affected tissue volume was observed (mean −4.2%; p = 0.81; SD 14.01). Thirteen (76.4%) participants reported clinical improvement (pain reduction, chronic bleeding resolution, functional improvement). Conclusion Despite functional improvement, the safety profile of low-dose taselisib precludes its long-term use.

Download Full-text

Reliability and validity of tissue volume measurement by three-dimensional ultrasound: an experimental model

Ultrasound in Obstetrics and Gynecology ◽

10.1002/uog.3916 ◽

2007 ◽

Vol 29 (2) ◽

pp. 210-214 ◽

Cited By ~ 28

Author(s):

W. P. Martins ◽

R. A. Ferriani ◽

D. A. Barra ◽

R. M. dos Reis ◽

M. A. V. Bortolieiro ◽

...

Keyword(s):

Experimental Model ◽

Three Dimensional ◽

Reliability And Validity ◽

Volume Measurement ◽

Tissue Volume

Download Full-text

Simultaneous acquisition of current and lateral force signals during AFM for characterising the piezoelectric and triboelectric effects of ZnO nanorods

Scientific Reports ◽

10.1038/s41598-021-82506-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Yijun Yang ◽

Kwanlae Kim

Keyword(s):

Linear Regression Analysis ◽

Zno Nanorods ◽

Lateral Force ◽

Mechanical Force ◽

Force Microscopy ◽

Atomic Force ◽

Simultaneous Acquisition ◽

Afm Probe ◽

Triboelectric Effect ◽

Conversion Efficiencies

AbstractAtomic force microscopy (AFM) is central to investigating the piezoelectric potentials of one-dimensional nanomaterials. The AFM probe is used to deflect individual piezoelectric nanorods and to measure the resultant current. However, the torsion data of AFM probes have not been exploited to elucidate the relationship between the applied mechanical force and resultant current. In this study, the effect of the size of ZnO nanorods on the efficiency of conversion of the applied mechanical force into current was investigated by simultaneously acquiring the conductive AFM and lateral force microscopy signals. The conversion efficiency was calculated based on linear regression analysis of the scatter plot of the data. This method is suitable for determining the conversion efficiencies of all types of freestanding piezoelectric nanomaterials grown under different conditions. A pixel-wise comparison of the current and lateral force images elucidated the mechanism of current generation from dense arrays of ZnO nanorods. The current signals generated from the ZnO nanorods by the AFM probe originated from the piezoelectric and triboelectric effects. The current signals contributed by the triboelectric effect were alleviated by using an AFM probe with a smaller spring constant and reducing the normal force.

Download Full-text

Cellular correlates of gray matter volume changes in magnetic resonance morphometry identified by two-photon microscopy

Scientific Reports ◽

10.1038/s41598-021-83491-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Livia Asan ◽

Claudia Falfán-Melgoza ◽

Carlo A. Beretta ◽

Markus Sack ◽

Lei Zheng ◽

...

Keyword(s):

Magnetic Resonance ◽

Cell Density ◽

Gray Matter ◽

Gray Matter Volume ◽

Cell Nuclei ◽

Cellular Mechanisms ◽

Tissue Volume ◽

Two Photon ◽

Matter Volume

AbstractMagnetic resonance imaging (MRI) of the brain combined with voxel-based morphometry (VBM) revealed changes in gray matter volume (GMV) in various disorders. However, the cellular basis of GMV changes has remained largely unclear. We correlated changes in GMV with cellular metrics by imaging mice with MRI and two-photon in vivo microscopy at three time points within 12 weeks, taking advantage of age-dependent changes in brain structure. Imaging fluorescent cell nuclei allowed inferences on (i) physical tissue volume as determined from reference spaces outlined by nuclei, (ii) cell density, (iii) the extent of cell clustering, and (iv) the volume of cell nuclei. Our data indicate that physical tissue volume alterations only account for 13.0% of the variance in GMV change. However, when including comprehensive measurements of nucleus volume and cell density, 35.6% of the GMV variance could be explained, highlighting the influence of distinct cellular mechanisms on VBM results.

Download Full-text