A Novel Method to Measure Mitral Valve Chordal Tension

2008 ◽  
Vol 131 (1) ◽  
Author(s):  
Zhaoming He ◽  
Christopher Jowers
Keyword(s):  
Mitral Valve ◽  
Force Sensor ◽  
New Method ◽  
Ring Size ◽  
Mitral Valves ◽  
Novel Method ◽  
Healthy Functioning ◽  
Leaflet Coaptation

Proper leaflet coaptation of the mitral valve is vital for a healthy functioning heart. Chordal tension directly affects leaflet coaptation. The C-shaped transducer used previously to measure chordal tension was too big for tension measurement of multiple chordae and their branches. A new method is needed to measure chordal tension with minimum interference with chord and leaflet motion. The method was to extrapolate longitudinal chordal tension from transverse chordal fibril force measured by inserting a small elliptical AIFP4 sensor from MicroStrain Inc. (Williston, VT) through a chord. Sensitivity of the method has been tested with the sensor implanted in chordae, and error of the method has been estimated at various sensor deviation angles. Intact porcine and ovine hearts were used to measure mitral valve strut and marginal chordal tensions at static transmitral pressures of 120mmHg and 160mmHg under an in vitro condition. The results obtained from the AIFP4 sensor were similar to the results obtained previously by C-shaped transducers in the porcine mitral valves. The sensor output errors increased with the increase in sensor deviation angle in the chord at a peak systolic tension. Strut chordal tensions of four ovine mitral valves of Edwards ring size M 28 were 0.29±0.06N at the transmitral pressure of 120mmHg. The tension of 18 porcine strut chordae of porcine mitral valves of Edwards ring size M 32 was 1.00±0.42N at the transmitral pressures of 120mmHg. The tension of 22 anterior leaflet marginal chordae from porcine mitral valves of Edwards ring size M 32 was 0.10±0.04N at the transmitral pressure of 120mmHg. A new method using an AIFP4 miniature force sensor to measure mitral valve chordal tension indirectly is successfully developed. This force sensor works well in measuring mitral valve chordal tension at an in vitro hydrostatic transmitral pressure. The size and simple fixation of the sensor make it favorable for chordal tension measurement of multiple chordae and their branches under in vitro or in vivo conditions with minimal interference with chordal geometry and dynamics.

A novel method for isolating spermatid nuclei from cytoplasm prior to ROSI in the mouse

Zygote ◽  
2004 ◽  
Vol 12 (4) ◽  
pp. 321-327 ◽  
Author(s):  
Satoshi Kishigami ◽  
Nguyen Van Thuan ◽  
Sayaka Wakayama ◽  
Takafusa Hikichi ◽  
Teruhiko Wakayama
Keyword(s):  
Round Spermatid ◽  
Separation Method ◽  
New Method ◽  
Offspring Production ◽  
Spermatid Nucleus ◽  
Novel Method ◽  
Round Spermatid Injection ◽  
Normal Fertilization

In the current widely used round spermatid injection (ROSI) protocol for the mouse, the spermatid nucleus is separated from most of the cytoplasm before ROSI by drawing a spermatid in and out of a pipette. This results in the highest rate of normal fertilization. However, this separation method is not always consistent and can be time-consuming. An alternative separation method that cuts away the cytoplasm using the tip of an injection pipette was developed. After removing the cytoplasm, ROSI was performed following both post- and pre-activation protocols and development in vitro and in vivo were examined. The new method consistently removed the bulk of the cytoplasm, as shown by quantifying mitochondria. ROSI without the cytoplasm resulted in significantly higher rates of fertilization than ROSI with the cytoplasm into either post- or pre-activated oocytes. Furthermore, the offspring production rates of ROSI without the cytoplasm were also high (50% and 49% for the post- and pre-activation protocols, respectively). This new method for separating the cytoplasm is an alternative way of producing offspring using ROSI.

Identification of Perilipin-2 as a lipid droplet protein regulated in oocytes during maturation

2010 ◽  
Vol 22 (8) ◽  
pp. 1262 ◽  
Author(s):  
Xing Yang ◽  
Kylie R. Dunning ◽  
Linda L.-Y. Wu ◽  
Theresa E. Hickey ◽  
Robert J. Norman ◽  
...  
Keyword(s):  
Lipid Droplet ◽  
Lipid Content ◽  
Lipid Droplets ◽  
Intracellular Lipids ◽  
Epidermal Growth ◽  
Novel Method ◽  
Perilipin 2 ◽  
Lipid Droplet Protein

Lipid droplet proteins regulate the storage and utilisation of intracellular lipids. Evidence is emerging that oocyte lipid utilisation impacts embryo development, but lipid droplet proteins have not been studied in oocytes. The aim of the present study was to characterise the size and localisation of lipid droplets in mouse oocytes during the periovulatory period and to identify lipid droplet proteins as potential biomarkers of oocyte lipid content. Oocyte lipid droplets, visualised using a novel method of staining cumulus–oocyte complexes (COCs) with BODIPY 493/503, were small and diffuse in oocytes of preovulatory COCs, but larger and more centrally located after maturation in response to ovulatory human chorionic gonadotrophin (hCG) in vivo, or FSH + epidermal growth factor in vitro. Lipid droplet proteins Perilipin, Perilipin-2, cell death-inducing DNA fragmentation factor 45-like effector (CIDE)-A and CIDE-B were detected in the mouse ovary by immunohistochemistry, but only Perilipin-2 was associated with lipid droplets in the oocyte. In COCs, Perilipin-2 mRNA and protein increased in response to ovulatory hCG. IVM failed to induce Perilipin-2 mRNA, yet oocyte lipid content was increased in this context, indicating that Perilipin-2 is not necessarily reflective of relative oocyte lipid content. Thus, Perilipin-2 is a lipid droplet protein in oocytes and its induction in the COC concurrent with dynamic reorganisation of lipid droplets suggests marked changes in lipid utilisation during oocyte maturation.

scholarly journals MicroRNAs in Valvular Heart Diseases: Biological Regulators, Prognostic Markers and Therapeutical Targets

2021 ◽  
Vol 22 (22) ◽  
pp. 12132
Author(s):  
Francesco Nappi ◽  
Adelaide Iervolino ◽  
Sanjeet Singh Avtaar Singh ◽  
Massimo Chello
Keyword(s):  
Mitral Valve ◽  
Mitral Valve Prolapse ◽  
Heart Diseases ◽  
Osteoblastic Differentiation ◽  
New Drugs ◽  
Expression Vectors ◽  
Chordae Tendineae ◽  
Valvular Heart Diseases

miRNAs have recently attracted investigators’ interest as regulators of valvular diseases pathogenesis, diagnostic biomarkers, and therapeutical targets. Evidence from in-vivo and in-vitro studies demonstrated stimulatory or inhibitory roles in mitral valve prolapse development, aortic leaflet fusion, and calcification pathways, specifically osteoblastic differentiation and transcription factors modulation. Tissue expression assessment and comparison between physiological and pathological phenotypes of different disease entities, including mitral valve prolapse and mitral chordae tendineae rupture, emerged as the best strategies to address miRNAs over or under-representation and thus, their impact on pathogeneses. In this review, we discuss the fundamental intra- and intercellular signals regulated by miRNAs leading to defects in mitral and aortic valves, congenital heart diseases, and the possible therapeutic strategies targeting them. These miRNAs inhibitors are comprised of antisense oligonucleotides and sponge vectors. The miRNA mimics, miRNA expression vectors, and small molecules are instead possible practical strategies to increase specific miRNA activity. Advantages and technical limitations of these new drugs, including instability and complex pharmacokinetics, are also presented. Novel delivery strategies, such as nanoparticles and liposomes, are described to improve knowledge on future personalized treatment directions.

scholarly journals CircKEAP1 Suppresses the Progression of Lung Adenocarcinoma via the miR-141-3p/KEAP1/NRF2 Axis

2021 ◽  
Vol 11 ◽  
Author(s):  
Yanbo Wang ◽  
Fenghai Ren ◽  
Dawei Sun ◽  
Jing Liu ◽  
BenKun Liu ◽  
...  
Keyword(s):  
Tumor Growth ◽  
Lung Adenocarcinoma ◽  
Expression Profiles ◽  
Luciferase Reporter ◽  
Tumor Tissues ◽  
Tumor Progress ◽  
Rna Immunoprecipitation ◽  
Novel Method

BackgroundLung cancer is the leading cause of death from cancer, and lung adenocarcinoma (LUAD) is the most common form. Despite the great advances that has been made in the diagnosis and treatment for LUAD, the pathogenesis of LUAD remains unclear. In this study, we aimed to identify the function of circKEAP1 derived from the exon of KEAP1 in LUAD.MethodsThe expression profiles of circRNAs in LUAD tissues and adjacent non-tumor tissues were analyzed by Agilent Arraystar Human CircRNA microarray. The levels and prognostic values of circKEAP1 in tissues and cancer cell lines were determined by quantitative real-time PCR (qRT-PCR). Subsequently, the effects of circKEAP1 on tumor growth were investigated by functional experiments in vitro and in vivo. Mechanistically, the dual luciferase reporter assay, RNA pull-down, and RNA immunoprecipitation experiments were performed to confirm the interaction between circKEAP1 and miR-141-3p in LUAD.ResultsWe found circKEAP1 was significantly downregulated in LUAD tissues and repressed tumor growth both in vitro and in vivo. Mechanistically, circKEAP1 competitively binds to miR-141-3p and relive miR-141-3p repression for its host gene, which activated the KEAP1/NRF2 signal pathway, and finally suppresses the tumor progress. Our findings suggest that circKEAP1 inhibits LUAD progression through circKEAP1/miR-141-3p/KEAP1 axis and it may serve as a novel method for the treatment of LUAD.

scholarly journals An in-vitro assay using human spermatozoa to detect toxicity of biologically active substances

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Tino Vollmer ◽  
Börje Ljungberg ◽  
Vera Jankowski ◽  
Joachim Jankowski ◽  
Griet Glorieux ◽  
...  
Keyword(s):  
Ex Vivo ◽  
Toxicity Testing ◽  
Biologically Active ◽  
Human Spermatozoa ◽  
Vitro Assay ◽  
Cellular Behavior ◽  
Novel Method ◽  
Set Up

Abstract Identifying the key toxic players within an in-vivo toxic syndrome is crucial to develop targeted therapies. Here, we established a novel method that characterizes the effect of single substances by means of an ex-vivo incubation set-up. We found that primary human spermatozoa elicit a distinct motile response on a (uremic) toxic milieu. Specifically, this approach describes the influence of a bulk toxic environment (uremia) as well as single substances (uremic toxins) by real-time analyzing motile cellular behavior. We established the human spermatozoa-based toxicity testing (HSTT) for detecting single substance-induced toxicity to be used as a screening tool to identify in-vivo toxins. Further, we propose an application of the HSTT as a method of clinical use to evaluate toxin-removing interventions (hemodialysis).

scholarly journals A novel method for measuring absolute coronary blood flow and microvascular resistance in patients with ischaemic heart disease

2020 ◽  
Author(s):  
Paul D Morris ◽  
Rebecca Gosling ◽  
Iwona Zwierzak ◽  
Holli Evans ◽  
Louise Aubiniere-Robb ◽  
...  
Keyword(s):  
Blood Flow ◽  
Heart Disease ◽  
Coronary Flow ◽  
Microvascular Disease ◽  
Flow Reserve ◽  
Catheter Laboratory ◽  
Novel Method ◽  
Microvascular Resistance

Abstract Aims Ischaemic heart disease is the reduction of myocardial blood flow, caused by epicardial and/or microvascular disease. Both are common and prognostically important conditions, with distinct guideline-indicated management. Fractional flow reserve (FFR) is the current gold-standard assessment of epicardial coronary disease but is only a surrogate of flow and only predicts percentage flow changes. It cannot assess absolute (volumetric) flow or microvascular disease. The aim of this study was to develop and validate a novel method that predicts absolute coronary blood flow and microvascular resistance (MVR) in the catheter laboratory. Methods and results A computational fluid dynamics (CFD) model was used to predict absolute coronary flow (QCFD) and coronary MVR using data from routine invasive angiography and pressure-wire assessment. QCFD was validated in an in vitro flow circuit which incorporated patient-specific, three-dimensional printed coronary arteries; and then in vivo, in patients with coronary disease. In vitro, QCFD agreed closely with the experimental flow over all flow rates [bias +2.08 mL/min; 95% confidence interval (error range) −4.7 to +8.8 mL/min; R2 = 0.999, P < 0.001; variability coefficient <1%]. In vivo, QCFD and MVR were successfully computed in all 40 patients under baseline and hyperaemic conditions, from which coronary flow reserve (CFR) was also calculated. QCFD-derived CFR correlated closely with pressure-derived CFR (R2 = 0.92, P < 0.001). This novel method was significantly more accurate than Doppler-wire-derived flow both in vitro (±6.7 vs. ±34 mL/min) and in vivo (±0.9 vs. ±24.4 mmHg). Conclusions Absolute coronary flow and MVR can be determined alongside FFR, in absolute units, during routine catheter laboratory assessment, without the need for additional catheters, wires or drug infusions. Using this novel method, epicardial and microvascular disease can be discriminated and quantified. This comprehensive coronary physiological assessment may enable a new level of patient stratification and management.

A Model for Non-Invasive Estimation of in Vivo Dialyzer Performances and Patient's Conductivity during Hemodialysis

1993 ◽  
Vol 16 (8) ◽  
pp. 585-591 ◽  
Author(s):  
T. Petitclerc ◽  
N. Goux ◽  
A.L. Reynier ◽  
B. Béné
Keyword(s):  
Strong Correlation ◽  
New Method ◽  
Conductivity Measurements ◽  
Urea Clearance ◽  
Non Invasive ◽  
Model Based ◽  
On Line ◽  
Conventional Methods

On-line monitoring of hemodialysis sessions requires a non-invasive estimation of the parameters concerning the patient's status and the dialyzer performances. We describe here a model based on a new method for non-invasive dialysance and patient conductivity measurements. In this technique the same probe measures alternately the conductivity at the dialysate inlet and outlet for two different dialysate conductivity values. From these data, an appropriate model allows to determine the patient's conductivity as well as the effective dialysance of ionised solutes, that is to say the dialysance corrected for recirculation. A strong correlation is evidenced between the effective dialysance measured by this method and the urea clearance measured by conventional methods (r=0.98 for in vitro solutions; r=0.82 in in vivo situations).

Hemoglobin radiolabeling: In vitro and in vivo comparison of iodine labeling with iodogen and a new method for technetium labeling

1989 ◽  
Vol 16 (4) ◽  
pp. 365-369 ◽  
Author(s):  
W.K. Bleeker ◽  
J. Van Der Plas ◽  
R.I.J. Feitsma ◽  
J. Agterberg ◽  
G. Rigter ◽  
...  
Keyword(s):  
New Method ◽  
Iodine Labeling

NOVEL POLYETHYLENIMINE NANOGELS AS POTENTIAL GENE CARRIERS PRODUCED VIA PHOTOCHEMISTRY IN SURFACTANT-FREE AQUEOUS SOLUTION

2006 ◽  
Vol 05 (06) ◽  
pp. 753-756 ◽  
Author(s):  
DONGMEI XU ◽  
JIAHUI YU ◽  
YONGBIAO LIU ◽  
HANWEN SUN ◽  
JINGYING XU ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Transfection Efficiency ◽  
In Vitro Tests ◽  
Gene Carriers ◽  
Polymeric Particles ◽  
Potential Applications ◽  
Novel Method ◽  
Low Toxicity

Cationic polymer nanogels, positively-charged submicrometer polymeric particles that swell in water, have attracted an increasing research attentions in recent years because of their potential applications as gene carriers. In this paper, we report a novel method to synthesize polyethylenimine (PEI) nanogels with sizes ranging from 80 nm to 200 nm via UV irradiation at room temperature in aqueous solution without adding any kind of surfactants. The morphology of the nanoparticles is determined to be spherical. The nanogels are of high stability, high transfection efficiency, low toxicity and low immunogenicity, as having been confirmed by in vivo tests with mice as an animal model, and by in vitro tests with human lung and liver cancer cells as well.

scholarly journals Validation test on 3d heart phantom for mitral valve leaflet tracking

2021 ◽  
Vol 22 (2) ◽  
pp. 717
Author(s):  
Lina Farhana Mahadi ◽  
Nabilah Ibrahim ◽  
Shahnoor Shanta ◽  
Hideyuki Hasegawa
Keyword(s):  
Mitral Valve ◽  
Water Tank ◽  
Font Size ◽  
Mitral Valve Leaflet ◽  
Mitral Valves ◽  
True Value ◽  
Video Frames ◽  
Validation Experiment ◽  
Temporal Rate

<p><span style="font-family: 'Times New Roman',serif; font-size: 9pt; mso-bidi-font-size: 11.0pt; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;" lang="EN-US"><span style="font-family: 'Times New Roman',serif; font-size: 9pt; mso-bidi-font-size: 11.0pt; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;" lang="EN-US">Mitral valve movement is essential to be identified in order to monitor the abnormality of blood flow in right side of heart. The estimation and tracking of mitral valve has seldom been investigated since it required high temporal rate to scan the echocardiography images and it depends on the operator to capture the low-speckle and-noise images. This study presents the validation experiment performed on heart phantom made of t</span><span style="font-family: 'Times New Roman',serif; font-size: 9pt; mso-bidi-font-size: 10.0pt; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;" lang="EN-US">hermoplastic polyurethane (TPU) filament which the objective is to validate the previous </span><span style="font-family: 'Times New Roman',serif; font-size: 9pt; mso-bidi-font-size: 11.0pt; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;" lang="EN-US">features tracking technique implemented in mitral valve locating in video frames using Kanade-Lucas-Tomasi (KLT) algorithm. The outcome was able to automatically detect the edge of mitral valve and thus in future, it manages to predict the flowing of blood pattern. An in-vitro experiment was conducted which involved a valve phantom scanning in water tank that connected to water pump. It was found in this study that the technique capable to detect and visualize the mitral valve up to 59 frames in 2.36 secondsby tracking the features of minimum eigenvalue within the selected region. It was also produced a good agreement of valve distance between the true value and the measured one, which achieved the minimum of 88% similarity. This yielded the validation of the proposed technique to track and visualize the mitral valves. </span></span></p>

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