MDCT Determination of Volume and Function of the Left Ventricle: Are Short-Axis Image Reformations Necessary?

The present knowledge of the three-dimensional structure of ribosomes is far too limited to enable a complete understanding of the various roles which ribosomes play in protein biosynthesis. The spatial arrangement of proteins and ribonuclec acids in ribosomes can be analysed in many ways. Determination of binding sites for individual proteins on ribonuclec acid and locations of the mutual positions of proteins on the ribosome using labeling with fluorescent dyes, cross-linking reagents, neutron-diffraction or antibodies against ribosomal proteins seem to be most successful approaches. Structure and function of ribosomes can be correlated be depleting the complete ribosomes of some proteins to the functionally inactive core and by subsequent partial reconstitution in order to regain active ribosomal particles.

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Development of a semi-automated segmentation tool for high frequency ultrasound image analysis of mouse echocardiograms

Scientific Reports ◽

10.1038/s41598-021-85971-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Kristi Powers ◽

Raymond Chang ◽

Justin Torello ◽

Rhonda Silva ◽

Yannick Cadoret ◽

...

Keyword(s):

Image Analysis ◽

Automated Analysis ◽

Structure And Function ◽

Ultrasound Images ◽

Cardiac Structure ◽

Short Axis ◽

Pixel Intensity ◽

Cardiac Structure And Function ◽

And Function

AbstractEchocardiography is a widely used and clinically translatable imaging modality for the evaluation of cardiac structure and function in preclinical drug discovery and development. Echocardiograms are among the first in vivo diagnostic tools utilized to evaluate the heart due to its relatively low cost, high throughput acquisition, and non-invasive nature; however lengthy manual image analysis, intra- and inter-operator variability, and subjective image analysis presents a challenge for reproducible data generation in preclinical research. To combat the image-processing bottleneck and address both variability and reproducibly challenges, we developed a semi-automated analysis algorithm workflow to analyze long- and short-axis murine left ventricle (LV) ultrasound images. The long-axis B-mode algorithm executes a script protocol that is trained using a reference library of 322 manually segmented LV ultrasound images. The short-axis script was engineered to analyze M-mode ultrasound images in a semi-automated fashion using a pixel intensity evaluation approach, allowing analysts to place two seed-points to triangulate the local maxima of LV wall boundary annotations. Blinded operator evaluation of the semi-automated analysis tool was performed and compared to the current manual segmentation methodology for testing inter- and intra-operator reproducibility at baseline and after a pharmacologic challenge. Comparisons between manual and semi-automatic derivation of LV ejection fraction resulted in a relative difference of 1% for long-axis (B-mode) images and 2.7% for short-axis (M-mode) images. Our semi-automatic workflow approach reduces image analysis time and subjective bias, as well as decreases inter- and intra-operator variability, thereby enhancing throughput and improving data quality for pre-clinical in vivo studies that incorporate cardiac structure and function endpoints.

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Assessment of the impact of nanoparticles on the activity of biomimetic membrane

Podstawy i Metody Oceny Środowiska Pracy ◽

10.5604/01.3001.0014.8153 ◽

2021 ◽

Vol XXXVII (1) ◽

pp. 89-100

Author(s):

Dorota Kondej

Keyword(s):

Occupational Safety ◽

Biological Membranes ◽

Structure And Function ◽

Lipid Monolayer ◽

Biomimetic Membranes ◽

Safety And Health ◽

Biomimetic Membrane ◽

And Function ◽

The Impact

This paper presents basic information on a structure and function of biological membranes. Types of biomimetic membranes modelling properties of biological membranes were introduced. The method of testing surface properties of a lipid monolayer, which is the basic type of biomimetic membranes, was described. The presented method makes it possible to evaluate the effect of nanoparticles on the surface activity of biomimetic membranes based on the determination of the surface index MA. This article discusses the problems of occupational safety and health, which are covered by health sciences and environmental engineering.

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Inter-Basal and Septal Connections of Papillary Muscles - An Anatomical Rationale for Rhythmic Opening of AV Valves - A Multicentric Medical College Based Cross Sectional Study

Journal of Evidence Based Medicine and Healthcare ◽

10.18410/jebmh/2021/523 ◽

2021 ◽

Vol 8 (31) ◽

pp. 2865-2869

Author(s):

Praveen Mulki Shenoy ◽

Amith Ramos ◽

Narasimha Pai ◽

Bharath Shetty ◽

Aravind Pallipady Rao

Keyword(s):

Left Ventricle ◽

Papillary Muscle ◽

Interventricular Septum ◽

Cross Sectional Study ◽

Papillary Muscles ◽

Cross Sectional ◽

Medical College ◽

Moderator Band ◽

Almost All ◽

And Function

BACKGROUND The papillary muscle basal connections have significant clinical implications. Variety of studies done on its morphology and function by various specialists in different departments. A close look on these revealed the interconnections of papillary muscles to one another and to the interventricular septum of both ventricles is related to uncoordinated contractions of papillary muscles, leading to hyper or hypokinesia or prolapse or even its rupture. METHODS Our study done in 25 formalin soaked hearts revealed after the deep and meticulous dissection, reflecting the walls of ventricles laterally the numerous interconnections of papillary muscles at its bases and IVS. Ventricles are opened by inverted ‘L’ shaped incision and its reflected more laterally till all the papillary muscles is visible in one frame after incising the moderator band. The connections were noted, measured, photographed, tabulated, compared with similar studies and analysed with experts with respective fields. RESULTS Almost all the specimens did have the interconnections. Further the post mortem findings of the cardiac related deaths with involvement of papillary muscles suggest damage to such ‘bridges’. The moderator band extensions to the base of right APM, and its extension to the posterior groups is noted in all the specimens. The bridge from the IVS to bases of both the groups of papillary muscles is noted in left ventricle. In90% of specimens the one PPM is found to be loosely connected, more so in left ventricle. CONCLUSIONS We are of a conclusion that such basal interconnections and to the interventricular septum are responsible for rhythmic contractions of papillary muscles of both ventricles. Since the AV valves have to open simultaneously, interconnections becomes mandatory as the impulse has to reach it before it reaches the trabeculae carniae. One of the Posterior papillary muscles is loosely connected to other papillary muscles, may be the reason for its rupture, more so in left ventricle. KEYWORDS Papillary Muscle, Interbasal Connection, Moderator Band, Valvular Prolapse, AV Valves

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Contrasting ischemic contraction patterns by zone and layer in canine myocardium

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1982.243.6.h852 ◽

1982 ◽

Vol 243 (6) ◽

pp. H852-H855 ◽

Cited By ~ 1

Author(s):

S. Hattori ◽

W. S. Weintraub ◽

J. B. Agarwal ◽

M. M. Bodenheimer ◽

V. S. Banka ◽

...

Keyword(s):

Coronary Artery ◽

Left Ventricle ◽

Fiber Orientation ◽

Coronary Occlusion ◽

Short Axis ◽

Circumflex Coronary Artery ◽

Left Circumflex Coronary Artery ◽

Close Relationship ◽

Canine Myocardium

The effect of graded coronary occlusion on myocardial shortening in different zones of the left ventricle is not clear. Therefore, in 15 dogs ultrasonic crystals were used to evaluate the effect of graded coronary occlusion on subendocardial and subepicardial contraction in both the left anterior descending coronary artery (LAD) and left circumflex coronary artery (Circ) distributions. Subepicardial shortening was evaluated along both the long and short axes. In the LAD zones, segment shortening decreased in parallel in the subendocardium and subepicardium. In the circumflex zone subendocardial and subepicardial long axis shortening fell off in parallel, while subepicardial short axis shortening fell off more rapidly. Thus there is a close relationship between endocardial and epicardial segment shortening following graded coronary occlusion. In the circumflex zone, however, fiber orientation may affect the measurement of segment motion.

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The Impact of Arthroscopic Capsular Release in Patients with Primary Frozen Shoulder on Shoulder Muscular Strength

BioMed Research International ◽

10.1155/2014/834283 ◽

2014 ◽

Vol 2014 ◽

pp. 1-5 ◽

Cited By ~ 5

Author(s):

Michał Waszczykowski ◽

Michał Polguj ◽

Jarosław Fabiś

Keyword(s):

Muscular Strength ◽

Frozen Shoulder ◽

Active Motion ◽

Capsular Release ◽

Arthroscopic Capsular Release ◽

Limited Function ◽

And Function ◽

The Impact

The aim of this study was to evaluate the impact of arthroscopic capsular release in patients with primary frozen shoulder on muscular strength of nonaffected and treated shoulder after at least two-year follow-up after the surgery. The assessment included twenty-seven patients, who underwent arthroscopic capsular release due to persistent limitation of range of passive and active motion, shoulder pain, and limited function of upper limb despite 6-month conservative treatment. All the patients underwent arthroscopic superior, anteroinferior, and posterior capsular release. After at least two-year follow-up, measurement of muscular strength of abductors, flexors, and external and internal rotators of the operated and nonaffected shoulder, as well as determination of range of motion (ROM) and function (ASES) in the operated and nonaffected shoulder, was performed. Measurement of muscular strength in the patient group did not reveal statistically significant differences between operated and nonaffected shoulder. The arthroscopic capsular release does not have significant impact on the decrease in the muscular strength of the operated shoulder.

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