scholarly journals Quantification of Endogenous Brain Tissue Displacement Imaging by Radiofrequency Ultrasound

Diagnostics ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 57 ◽  
Author(s):  
Rytis Jurkonis ◽  
Monika Makūnaitė ◽  
Mindaugas Baranauskas ◽  
Arūnas Lukoševičius ◽  
Andrius Sakalauskas ◽  
...  
Keyword(s):  
Brain Tissue ◽  
Tissue Characterization ◽  
Pearson Correlation ◽  
Ultrasonic Transducer ◽  
Regional Distribution ◽  
Diagnostic System ◽  
Preclinical Study ◽  
Elderly Subjects ◽  
Healthy Elderly

The purpose of this paper is a quantification of displacement parameters used in the imaging of brain tissue endogenous motion using ultrasonic radiofrequency (RF) signals. In a preclinical study, an ultrasonic diagnostic system with RF output was equipped with dedicated signal processing software and subject head–ultrasonic transducer stabilization. This allowed the use of RF scanning frames for the calculation of micrometer-range displacements, excluding sonographer-induced motions. Analysis of quantitative displacement estimates in dynamical phantom experiments showed that displacements of 55 µm down to 2 µm were quantified as confident according to Pearson correlation between signal fragments (minimum p ≤ 0.001). The same algorithm and scanning hardware were used in experiments and clinical imaging which allows translating phantom results to Alzheimer’s disease patients and healthy elderly subjects as examples. The confident quantitative displacement waveforms of six in vivo heart-cycle episodes ranged from 8 µm up to 263 µm (Pearson correlation p ≤ 0.01). Displacement time sequences showed promising possibilities to evaluate the morphology of endogenous displacement signals at each point of the scanning plane, while displacement maps—regional distribution of displacement parameters—were essential for tissue characterization.

scholarly journals A human antibody selective for transthyretin amyloid removes cardiac amyloid through phagocytic immune cells

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Aubin Michalon ◽  
Andreas Hagenbuch ◽  
Christian Huy ◽  
Evita Varela ◽  
Benoit Combaluzier ◽  
...  
Keyword(s):  
Immune Cells ◽  
Ex Vivo ◽  
Phase 1 ◽  
Hereditary Disease ◽  
Elderly Subjects ◽  
Human Antibody ◽  
Cardiac Amyloid ◽  
Healthy Elderly ◽  
Ongoing Phase

AbstractTransthyretin amyloid (ATTR) cardiomyopathy is a debilitating disease leading to heart failure and death. It is characterized by the deposition of extracellular ATTR fibrils in the myocardium. Reducing myocardial ATTR load is a therapeutic goal anticipated to translate into restored cardiac function and improved patient survival. For this purpose, we developed the selective anti-ATTR antibody NI301A, a recombinant human monoclonal immunoglobulin G1. NI301A was cloned following comprehensive analyses of memory B cell repertoires derived from healthy elderly subjects. NI301A binds selectively with high affinity to the disease-associated ATTR aggregates of either wild-type or variant ATTR related to sporadic or hereditary disease, respectively. It does not bind physiological transthyretin. NI301A removes ATTR deposits ex vivo from patient-derived myocardium by macrophages, as well as in vivo from mice grafted with patient-derived ATTR fibrils in a dose- and time-dependent fashion. The biological activity of ATTR removal involves antibody-mediated activation of phagocytic immune cells including macrophages. These data support the evaluation of safety and tolerability of NI301A in an ongoing phase 1 clinical trial in patients with ATTR cardiomyopathy.

scholarly journals Arginine behaviour after arginine or citrulline administration in older subjects

2015 ◽  
Vol 115 (3) ◽  
pp. 399-404 ◽  
Author(s):  
C. Moinard ◽  
J. Maccario ◽  
S. Walrand ◽  
V. Lasserre ◽  
J. Marc ◽  
...  
Keyword(s):  
Plasma Concentrations ◽  
The Elderly ◽  
Volume Of Distribution ◽  
Elderly Subjects ◽  
Healthy Elderly ◽  
Age Related ◽  
Loading Tests ◽  
Kinetics Of ◽  
Healthy Elderly Subjects

AbstractArginine (ARG) and its precursor citrulline (CIT) are popular dietary supplements, especially for the elderly. However, age-related reductions in lean body mass and alterations in organ functions could change their bioavailability. Pharmacokinetics and tolerance to amino acid (AA) loads are poorly documented in elderly subjects. The objective here was to characterise the plasma kinetics of CIT and ARG in a single-dosing study design. Eight fasting elderly men underwent two separate isomolar oral loading tests (10 g of CIT or 9·94 g of ARG). Blood was withdrawn over an 8-h period to measure plasma AA concentrations. Only CIT, ornithine and ARG plasma concentrations were changed. Volume of distribution was not dependent on AA administered. Conversely, parameters related to ARG kinetics were strongly dependent on AA administered: after ARG load, elimination was higher (ARG>CIT; P=0·041) and admission period+time at peak concentration was lower (ARG<CIT; P=0·033), and the combination of both phenomena results in a marked increase in ARG availability when CIT was administered (ARG<CIT; P=0·033) compared with ARG administration itself. In conclusion, a single CIT administration in the elderly is safe and well tolerated, and CIT proves to be a better in vivo ARG precursor than ARG itself in healthy elderly subjects.

scholarly journals Prospective evaluation of protein bound vitamin B12(cobalamin) malabsorption in the elderly using trout flesh labelled in vivo with 57Co-cobalamin

Gut ◽  
1997 ◽  
Vol 41 (4) ◽  
pp. 475-479 ◽  
Author(s):  
I Aimone-Gastin ◽  
H Pierson ◽  
C Jeandel ◽  
J P Bronowicki ◽  
F Plénat ◽  
...  
Keyword(s):  
Elderly Patients ◽  
Pancreatic Insufficiency ◽  
Intrinsic Factor ◽  
Elderly Subjects ◽  
Blood Levels ◽  
Vitamin B ◽  
Healthy Elderly ◽  
Schilling Test ◽  
Hospitalised Patients

Background—The frequency of dietary protein bound vitamin B12 malabsorption in elderly patients remains controversial.Aims—To evaluate this malabsorption in elderly hospitalised patients using a modified Schilling test.Patients—Fourteen elderly patients with low B12 blood levels were prospectively selected from 394 hospitalised patients.Methods—The modified Schilling test was performed with trout labelled in vivo.Results—The test was normal in five healthy elderly subjects, in 7/8 patients with pancreatic insufficiency, and in nine non-elderly patients with antral gastritis. The low decision limit was established at 3.3% (median 4.8%). From the 14 elderly patients with low B12 prospectively selected from 394 hospitalised patients, seven had a real deficiency with anaemia and an increased homocysteine and/or methylmalonate serum level. The modified Schilling test showed malabsorption in five of these patients, including two in which the standard Schilling test was normal, and three in which the standard Schilling test was partially corrected by an intrinsic factor.Conclusions—Protein bound vitamin B12malabsorption was detected in at least 0.5% of elderly hospitalised patients, using the labelled trout flesh absorption test.

scholarly journals Single-Shot Waterless Low-Profile Photoacoustic System: Near-Field Volumetric Imaging In Vivo for Blood Vessels Based on Capacitive Micromachined Ultrasonic Transducer (CMUT)

Sensors ◽  
2019 ◽  
Vol 19 (5) ◽  
pp. 995 ◽  
Author(s):  
Won Choi ◽  
Young Kim ◽  
Hyeong Jo ◽  
Joo Pyun ◽  
Soo Kwon ◽  
...  
Keyword(s):  
Tissue Characterization ◽  
Imaging System ◽  
Ultrasonic Transducer ◽  
Near Field ◽  
Center Frequency ◽  
Single Shot ◽  
Living Body ◽  
Low Profile ◽  
Capacitive Micromachined Ultrasonic Transducer

Intensive research on photoacoustics (PA) for imaging of the living human body, including the skin, vessels, and tumors, has recently been conducted. We propose a PA measurement system based on a capacitive micromachined ultrasonic transducer (CMUT) with waterless coupling, short measurement time (<1 s), backward light irradiation, and a low-profile ultrasonic receiver unit (<1 cm). We fabricate a 64-element CMUT ring array with 6.2 mm diameter and 10.4 MHz center frequency in air, and 100% yield and uniform element response. To validate the PA tissue characterization, we employ pencil lead and red ink as solid and liquid models, respectively, and a living body to target moles and vessels. The system implements a near-field imaging system consisting of a 6 mm polydimethylsiloxane (PDMS) matching layer between the object and CMUT, which has a 3.7 MHz center frequency in PDMS. Experiments were performed in a waterless contact on the PDMS and the laser was irradiated with a 1 cm diameter. The experimental results show the feasibility of this near-field PA imaging system for position and depth detection of skin, mole, vessel cells, etc. Therefore, a system applicable to a low-profile compact biomedical device is presented.

scholarly journals The Acetylcholine Index: An Electroencephalographic Marker of Cholinergic Activity in the Living Human Brain Applied to Alzheimer's Disease and Other Dementias

2014 ◽  
Vol 39 (3-4) ◽  
pp. 132-142 ◽  
Author(s):  
Magnus Johannsson ◽  
Jon Snaedal ◽  
Gisli Holmar Johannesson ◽  
Thorkell Eli Gudmundsson ◽  
Kristinn Johnsen
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Human Brain ◽  
Elderly Subjects ◽  
Cholinergic Activity ◽  
Healthy Elderly ◽  
Age Related ◽  
General Decline ◽  
Using Data

Background: The cholinergic hypothesis is well established and has led to the development of pharmacological treatments for Alzheimer's disease (AD). However, there has previously been no physiological means of monitoring cholinergic activity in vivo. Methods: An electroencephalography (EEG)-based acetylcholine (Ach) index reflecting the cholinergic activity in the brain was developed using data from a scopolamine challenge study. The applicability of the Ach index was examined in an elderly population of healthy controls and patients suffering from various causes of cognitive decline. Results: The Ach index showed a strong reduction in the severe stages of AD dementia. A high correlation was demonstrated between the Ach index and cognitive function. The index was reduced in patients with mild cognitive impairment and prodromal AD, indicating a decreased cholinergic activity. When considering the distribution of the Ach index in a population of healthy elderly subjects, an age-related threshold was revealed, beyond which there is a general decline in cholinergic activity. Conclusions: The EEG-based Ach index provides, for the first time, a physiological means of monitoring the cholinergic activity in the human brain in vivo. This has great potential for aiding diagnosis and patient stratification as well as for monitoring disease progression and treatment response. © 2014 S. Karger AG, Basel

scholarly journals Hubungan serum seng dengan jumlah CD4 pada lansia di Panti Jompo

2014 ◽  
Vol 2 (1) ◽  
Author(s):  
Maria Widijanti Sugeng ◽  
Merryana Adriani ◽  
Bambang Wirjatmadi
Keyword(s):  
Immune System ◽  
Zinc Deficiency ◽  
Pearson Correlation ◽  
The Elderly ◽  
Cross Sectional Study ◽  
Zinc Level ◽  
Cd4 Count ◽  
Elderly Subjects ◽  
Cross Sectional ◽  
Healthy Elderly

Background: Elderly people tend to have higher susceptibility to infections because of immune dysfunction, especially cell-mediated immune system which is related to zinc deficiency. Zinc has an important role in the cell-mediated immune system which can be determined by CD4 count. Objectives: To determine the zinc level in the serum and CD4 count in healthy elderly and the correlation between the zinc level in the serum and CD4 count. Method: This was a randomized cross-sectional study. Twenty seven healthy elderly subjects of both sexes aged 60-90 years were recruited for this study from a senior center. Zinc level in the serum and CD4 count were measured. Result: The average of CD4 count was 710 + 269 cells/ml, and the average of zinc level in the serum was 87,29 + 10,27 μg/dL. Twenty six percent elderly had low CD4 count (<460cells/ml. There was no zinc deficiency among the elderly but 30% elderly had zinc level 70- 80 μg/dL. There was a significant correlation (p<0,05) between zinc level and CD4 count, which was analyzed using Pearson correlation method.Conclusion: CD4 count has correlation with zinc level in the serum in elderlyKeywords: Zinc level, CD4 count, elderly

scholarly journals Biomarker-Based Signature of Alzheimer’s Disease in Pre-MCI Individuals

2019 ◽  
Vol 9 (9) ◽  
pp. 213 ◽  
Author(s):  
Elena Chipi ◽  
Nicola Salvadori ◽  
Lucia Farotti ◽  
Lucilla Parnetti
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Subjective Experience ◽  
Clinical Symptoms ◽  
Clinical Stage ◽  
Elderly Subjects ◽  
Healthy Elderly ◽  
Risk Of Progression ◽  
Disease Modifying Agents

Alzheimer’s disease (AD) pathology begins decades before the onset of clinical symptoms. It is recognized as a clinicobiological entity, being detectable in vivo independently of the clinical stage by means of pathophysiological biomarkers. Accordingly, neuropathological studies that were carried out on healthy elderly subjects, with or without subjective experience of cognitive decline, reported evidence of AD pathology in a high proportion of cases. At present, mild cognitive impairment (MCI) represents the only clinically diagnosed pre-dementia stage. Several attempts have been carried out to detect AD as early as possible, when subtle cognitive alterations, still not fulfilling MCI criteria, appear. Importantly, pre-MCI individuals showing the positivity of pathophysiological AD biomarkers show a risk of progression similar to MCI patients. In view of successful treatment with disease modifying agents, in a clinical setting, a timely diagnosis is mandatory. In clinical routine, biomarkers assessment should be taken into consideration whenever a subject with subtle cognitive deficits (pre-MCI), who is aware of his/her decline, requests to know the cause of such disturbances. In this review, we report the available neuropsychological and biomarkers data that characterize the pre-MCI patients, thus proposing pre-MCI as the first clinical manifestation of AD.

Quantitative aspects of glucose production and metabolism in healthy elderly subjects

Diabetes ◽  
1982 ◽  
Vol 31 (3) ◽  
pp. 203-211 ◽  
Author(s):  
J. J. Robert ◽  
J. C. Cummins ◽  
R. R. Wolfe ◽  
M. Durkot ◽  
D. E. Matthews ◽  
...  
Keyword(s):  
Glucose Production ◽  
Elderly Subjects ◽  
Healthy Elderly ◽  
Healthy Elderly Subjects
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