Cellular characteristics of wool follicles and fibres in finewool and strongwool Merinos

1992 ◽  
Vol 43 (2) ◽  
pp. 355 ◽  
Author(s):  
JEH Edwards ◽  
PI Hynd
Keyword(s):  
Linear Regression ◽  
Unit Area ◽  
Cortical Cell ◽  
Fibre Production ◽  
Structure And Function ◽  
Strain Variation ◽  
Average Volume ◽  
Stepwise Linear Regression ◽  
Single Character ◽  
And Function

The genetic differences in the structure and function of wool follicles and their association with wool and fibre production were examined in 6 finewool Merinos (Camden Park) and 6 strongwool Merinos (East Bungaree). The strongwool Merinos produced 2.4 times more wool per unit area of skin and 3.5 times the volume of fibre per follicle than the finewool Merinos, when both groups were maintained under similar environmental conditions. The finewool Merinos had a higher follicle density, but a lower average volume of germinative tissue in the follicle bulb and the skin, than the strongwool Merinos. The number and volume of cells in the bulb, bulb cell production rate, cortical cell size and the proportion of bulb cells entering the fibre tended to be greater in the strongwool Merinos than the finewool Merinos, but were not statistically different between strains due to a high between-sheep, within-strain variation. In a stepwise linear regression, wool production per unit area was best predicted by the volume of germinative tissue in the bulb, together with follicle density. It is concluded that genotype determines the volume of potential mitotically-active tissue in the skin, however the dynamic mechanism of fibre production is not controlled by a single character, but rather a combination of a number of characteristics.

Abstract 17449: Left Ventricular Hypertrophy and Reduced Myocardial Function Are Associated with Aortic stiffness Measured by Cardiac MRI: the Multi-Ethnic Study of Atherosclerosis (MESA)

Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Yoshiaki Ohyama ◽  
Bharath Ambale-Venkatesh ◽  
Atul R Chught ◽  
Gisera Teixido-Tura ◽  
Jang Young Kim ◽  
...  
Keyword(s):  
Risk Factors ◽  
Linear Regression ◽  
Regression Models ◽  
Structure And Function ◽  
Cine Mri ◽  
Linear Regression Models ◽  
Ethnic Study ◽  
Lv Mass ◽  
Multivariable Models ◽  
And Function

Background: Aortic pulse velocity (PWV) is generally considered an intrinsic marker of arterial stiffness. The association of central aortic PWV measured by MRI with cardiac structure and function remains poorly explored. We investigated how central aortic PWV assessed by MRI relates to LV structure and function in the population based study. Method: Multi-Ethnic Study of Atherosclerosis (MESA) participants at exam5 (2010-2012) were studied. Central aortic PWV was measured by phase contrast (PC) cine MRI at the level of the pulmonary artery bifurcation and black blood sagittal image. LV mass and volume indexed to height1.7, LV ejection fraction (LVEF), and LV mass volume ratio (M/V ratio) were determined by cine MRI. LV circumferential strain (Ecc), LV torsion, and early diastolic strain rate (SRe) were determined from tagged MRI. Linear regression models were used to evaluate the association between PWV and LV parameters after adjusting for demographics and cardiovascular risk factors. Results: A total of 2018 participants (age 70 ± 9 years, 53% women, 38% White, 10% Chinese, 28% African American, 24% Hispanic) were included in this cross-sectional study. Mean value of PWV was 8.9 ± 4.2 m/s. Distribution of PWV was skewed, so PWV was logarithmically transformed for linear regression models. In multivariable models adjusted for risk factors, higher PWV was associated with less/worse myocardial systolic and diastolic function parameters; LVEF, Ecc, torsion and SRe. Higher PWV was also associated with higher LV mass before and after adjusting multivariable models (Table). Conclusion: Our observations indicate that higher PWV is related to LV hypertrophy and subclinical myocardial systolic and diastolic dysfunction in multi-ethnic population.

Structure and function of neural networks in the retina

1988 ◽  
Vol 46 ◽  
pp. 26-27
Author(s):  
Peter Sterling
Keyword(s):  
Ganglion Cells ◽  
Three Dimensional ◽  
Structure And Function ◽  
Synaptic Connections ◽  
Visual Axis ◽  
One Dimensional ◽  
Cat Retina ◽  
Ultrathin Sections ◽  
And Function ◽  
Insight Into

The synaptic connections in cat retina that link photoreceptors to ganglion cells have been analyzed quantitatively. Our approach has been to prepare serial, ultrathin sections and photograph en montage at low magnification (˜2000X) in the electron microscope. Six series, 100-300 sections long, have been prepared over the last decade. They derive from different cats but always from the same region of retina, about one degree from the center of the visual axis. The material has been analyzed by reconstructing adjacent neurons in each array and then identifying systematically the synaptic connections between arrays. Most reconstructions were done manually by tracing the outlines of processes in successive sections onto acetate sheets aligned on a cartoonist's jig. The tracings were then digitized, stacked by computer, and printed with the hidden lines removed. The results have provided rather than the usual one-dimensional account of pathways, a three-dimensional account of circuits. From this has emerged insight into the functional architecture.

Osseointegration interface of calcified bone and endosseous implants

1992 ◽  
Vol 50 (2) ◽  
pp. 1096-1097
Author(s):  
K.E. Krizan ◽  
J.E. Laffoon ◽  
M.J. Buckley
Keyword(s):  
Structure And Function ◽  
Titanium Implants ◽  
En Bloc ◽  
Endosseous Implants ◽  
Ultrastructural Studies ◽  
The Past ◽  
Cacodylate Buffer ◽  
One Year ◽  
And Function

With increase use of tissue-integrated prostheses in recent years it is a goal to understand what is happening at the interface between haversion bone and bulk metal. This study uses electron microscopy (EM) techniques to establish parameters for osseointegration (structure and function between bone and nonload-carrying implants) in an animal model. In the past the interface has been evaluated extensively with light microscopy methods. Today researchers are using the EM for ultrastructural studies of the bone tissue and implant responses to an in vivo environment. Under general anesthesia nine adult mongrel dogs received three Brånemark (Nobelpharma) 3.75 × 7 mm titanium implants surgical placed in their left zygomatic arch. After a one year healing period the animals were injected with a routine bone marker (oxytetracycline), euthanized and perfused via aortic cannulation with 3% glutaraldehyde in 0.1M cacodylate buffer pH 7.2. Implants were retrieved en bloc, harvest radiographs made (Fig. 1), and routinely embedded in plastic. Tissue and implants were cut into 300 micron thick wafers, longitudinally to the implant with an Isomet saw and diamond wafering blade [Beuhler] until the center of the implant was reached.

Use of human autoantibodies and immunoelectron microscopy to study structure and function of the nucleolus and nuclear bodies

1992 ◽  
Vol 50 (1) ◽  
pp. 506-507
Author(s):  
Robert L. Ochs
Keyword(s):  
Electron Microscopy ◽  
Structure And Function ◽  
Nuclear Bodies ◽  
Nuclear Interior ◽  
Coiled Bodies ◽  
Interchromatin Granules ◽  
And Function ◽  
Conventional Electron Microscopy ◽  
Perichromatin Granules ◽  
Perichromatin Fibrils

By conventional electron microscopy, the formed elements of the nuclear interior include the nucleolus, chromatin, interchromatin granules, perichromatin granules, perichromatin fibrils, and various types of nuclear bodies (Figs. 1a-c). Of these structures, all have been reasonably well characterized structurally and functionally except for nuclear bodies. The most common types of nuclear bodies are simple nuclear bodies and coiled bodies (Figs. 1a,c). Since nuclear bodies are small in size (0.2-1.0 μm in diameter) and infrequent in number, they are often overlooked or simply not observed in any random thin section. The rat liver hepatocyte in Fig. 1b is a case in point. Historically, nuclear bodies are more prominent in hyperactive cells, they often occur in proximity to nucleoli (Fig. 1c), and sometimes they are observed to “bud off” from the nucleolar surface.

Depletion and Reconstitution of Active E. Coli Ribosomes

1975 ◽  
Vol 33 ◽  
pp. 640-641
Author(s):  
M. Boublik ◽  
W. Hellmann ◽  
F. Jenkins
Keyword(s):  
Protein Biosynthesis ◽  
Large Subunit ◽  
High Resolution Electron Microscopy ◽  
Small Subunit ◽  
Structure And Function ◽  
Biologically Active ◽  
Biological Macromolecules ◽  
E Coli ◽  
Resolution Electron ◽  
And Function

Correlations between structure and function of biological macromolecules have been studied intensively for many years, mostly by indirect methods. High resolution electron microscopy is a unique tool which can provide such information directly by comparing the conformation of biopolymers in their biologically active and inactive state. We have correlated the structure and function of ribosomes, ribonucleoprotein particles which are the site of protein biosynthesis. 70S E. coli ribosomes, used in this experiment, are composed of two subunits - large (50S) and small (30S). The large subunit consists of 34 proteins and two different ribonucleic acid molecules. The small subunit contains 21 proteins and one RNA molecule. All proteins (with the exception of L7 and L12) are present in one copy per ribosome.This study deals with the changes in the fine structure of E. coli ribosomes depleted of proteins L7 and L12. These proteins are unique in many aspects.

The Laryngeal Epithelium in Reflux

2011 ◽  
Vol 21 (3) ◽  
pp. 112-117 ◽  
Author(s):  
Elizabeth Erickson-Levendoski ◽  
Mahalakshmi Sivasankar
Keyword(s):  
Laryngopharyngeal Reflux ◽  
Critical Role ◽  
Structure And Function ◽  
Laryngeal Disease ◽  
Health And Disease ◽  
And Function ◽  
The Impact

The epithelium plays a critical role in the maintenance of laryngeal health. This is evident in that laryngeal disease may result when the integrity of the epithelium is compromised by insults such as laryngopharyngeal reflux. In this article, we will review the structure and function of the laryngeal epithelium and summarize the impact of laryngopharyngeal reflux on the epithelium. Research investigating the ramifications of reflux on the epithelium has improved our understanding of laryngeal disease associated with laryngopharyngeal reflux. It further highlights the need for continued research on the laryngeal epithelium in health and disease.

Structure and function in the spermatozoon of Bacillus rossiusThe spermatozoon of arthropoda. XIX

1973 ◽  
Vol 44 (1-21012) ◽  
pp. 1-1 ◽  
Author(s):  
B BACCETTI ◽  
A BURRINI ◽  
R DALLAI ◽  
V PALLINI ◽  
P PERITI ◽  
...  
Keyword(s):  
Structure And Function ◽  
And Function
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