Magnetic resonance image attributes of the bovine ovarian follicle antrum during development and regression

The magnetic resonance images and maps of bovine ovaries acquired at defined phases of follicular development and regression were studied to determine whether magnetic resonance image attributes of the follicular antrum reflect the physiological status of dominant and subordinate ovarian follicles. Ovariectomies were performed at day 3 of wave one, day 6 of wave one, day 1 of wave two and at >/= day 17 after ovulation. The timings of ovariectomies were selected to acquire growing, early static, late static and regressing follicles of the first wave and preovulatory follicles of the ovulatory wave. Pre-selection and subordinate follicles were also available for analysis. Serum samples were taken on the day of ovariectomy and follicular fluid samples were taken after imaging. Numerical pixel value and pixel heterogeneity in a spot representing approximately 95% of the follicular antrum were quantified in T(1)- and T(2)-weighted images. T(1) and T(2) relaxation rates (T(1) and T(2)), proton density, apparent diffusion coefficients and their heterogeneities were determined from the computed magnetic resonance maps. The antra of early atretic dominant follicles showed higher T(2)-weighted mean pixel value (P < 0.008) and heterogeneity (P < 0. 01) and lower T(2) heterogeneity (P < 0.008) than growing follicles. Subordinate follicles in the presence of a preovulatory dominant follicle had higher T(1), T(1) heterogeneity, proton density, proton density heterogeneity, and lower mean pixel value in T(1)-weighted images than subordinate follicles of the anovulatory wave (P < 0.04). T(1) relaxation rate heterogeneity and proton density heterogeneity were positively correlated with follicular fluid oestradiol concentration (r = 0.4 and 0.3; P < 0.04). T(2) relaxation rate heterogeneity was positively correlated with follicular fluid progesterone concentration (r = 0.4; P < 0.008). Quantitative differences in magnetic resonance image attributes of the antrum observed among phases of follicular development and regression coincided with changes in the ability of the dominant follicle to produce steroid hormones and ovulate, and thus were indicative of physiological status and follicular health.

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Relationships between concentrations of steroids, igf-1 and igf binding proteins during follicular development in the ewe

Proceedings of the British Society of Animal Science ◽

10.1017/s0308229600028245 ◽

1995 ◽

Vol 1995 ◽

pp. 56-56

Author(s):

M. Khalid ◽

W. Haresign

Keyword(s):

Follicular Fluid ◽

Biochemical Markers ◽

Binding Proteins ◽

Ovarian Function ◽

Follicular Development ◽

Physiological Status ◽

Igf Binding Proteins ◽

Ovarian Cells ◽

Igf Binding

Insulin-like growth factor-1 (IGF-1) is one of the potential autocrine/paracrine regulators of ovarian function. Not only do relationships exist between follicular fluid concentrations of IGF-1 and various biochemical markers of follicular differentiation, but IGF-1 has also been shown to stimulate both proliferation and steroidogenesis in ovarian cells in vitro (Adashi et al., 1985). The actions of IGF-1 are thought to be modulated by IGF-binding proteins (IGFBPs). Indeed, follicular growth and atresia in the ewe have been reported to be determined more by changes in IGFBPs than by changes in IGF-1 (Monget et al., 1993). However, in mat particular study, stage of follicular development was determined by follicle size and by microscopic examination of the granulosa cells of individual follicles rather than by biochemical markers of follicle status. The objective of the present study was, therefore, to investigate changes in IGF-1 and IGFBPs levels in follicular fluid and to relate these to the physiological status as determined by steroidogenic content of follicular fluid.

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Coronal proton density weighted magnetic resonance image of a 9 year old child's left ankle and foot

BMJ ◽

10.1136/bmj.g7702 ◽

2014 ◽

Vol 349 (dec18 11) ◽

pp. g7702-g7702

Author(s):

O. Kayode ◽

S. Perera

Keyword(s):

Magnetic Resonance ◽

Magnetic Resonance Image ◽

Proton Density ◽

Left Ankle ◽

Ankle And Foot

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Nuclear magnetic resonance surface relaxation mechanisms of kerogen

Geophysics ◽

10.1190/geo2016-0350.1 ◽

2017 ◽

Vol 82 (6) ◽

pp. JM15-JM22 ◽

Cited By ~ 8

Author(s):

Boyang Zhang ◽

Hugh Daigle

Keyword(s):

Nuclear Magnetic Resonance ◽

Hydrogen Bonding ◽

Magnetic Resonance ◽

Relaxation Rate ◽

Dipolar Coupling ◽

Surface Relaxation ◽

Proton Density ◽

Transverse Relaxation Rate ◽

Pore Fluids ◽

Transverse Relaxation

Nuclear magnetic resonance (NMR) relaxometry is an excellent tool for probing the interactions between solid pore surface and pore fluids in porous media. Surface relaxation is a key component of NMR relaxation. It is well-known that in conventional rocks, paramagnetic centers contribute most to the surface relaxation phenomenon. However, the interactions between organic pore surfaces and pore fluids, and the mechanism of surface relaxation in organic shale pores, are not well-understood. We tackle the issue using deuterated compounds to adjust the proton density in the liquid phase and monitoring the transverse relaxation rate changes of kerogen-fluid mixtures. With the Barnett and Eagle Ford kerogen isolates, we found that for alkanes, it is intramolecular dipolar coupling that dominates among the magnetic interactions. As a result, the transverse relaxation rate of alkane proton spins is more likely to be dependent on the concentration of active adsorption sites on the kerogen surface, rather than the kerogen proton density. For water inside organic pores, surface relaxation most likely originates from hydrogen bonding and intermolecular dipolar coupling. We also examined the temperature effect on kerogen surface relaxation and found temperature-dependent behavior that is consistent with surface relaxation by hydrogen bonding and homonuclear dipolar coupling interactions.

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Analysis of the variations of follicular fluid composition during follicular growth and maturation in the mare using proton nuclear magnetic resonance (1H NMR)

Reproduction ◽

10.1530/rep.0.1240241 ◽

2002 ◽

pp. 241-248 ◽

Cited By ~ 55

Author(s):

N Gerard ◽

S Loiseau ◽

G Duchamp ◽

F Seguin

Keyword(s):

Amino Acids ◽

Follicular Fluid ◽

Follicular Development ◽

Proton Nuclear Magnetic Resonance ◽

Follicular Growth ◽

Dominant Follicle ◽

Follicular Maturation ◽

H Nmr ◽

Sugar Chains ◽

Glucose Metabolites

Follicular development and ovulatory processes in mammals involve local biochemical changes as a result of substantial modifications in cellular metabolism, the most well known of which is steroid variation. In the present study, the intrafollicular variation of several other components was studied using proton nuclear magnetic resonance ((1)H NMR). This approach made it possible to demonstrate that the intrafollicular biochemical content changes during follicular growth and maturation. Follicular fluid was aspirated by ovarian puncture of the dominant follicle at various physiological stages of its development: early dominant, late dominant and preovulatory. Serum samples were collected during each puncture session. (1)H NMR was used to evaluate intrafollicular and circulating glycoconjugates (sugar chains and N-acetyl groups), lipoproteins (CH(3) and CH(2) groups), glucose metabolites (trimethylamines, acetate and lactate), amino acids (glutamine/glutamate and alanine), creatine/creatinine and polyamines. Follicular fluids were assayed by radioimmunoassay for oestradiol and progesterone contents. The intrafollicular contents of alanine and lipoproteins (CH(3) groups) decreased in the dominant follicle during growth, whereas concentrations of progesterone and oestradiol increased significantly. After injection of gonadotrophin to induce ovulation, follicular maturation was characterized by a decrease in glycoconjugates (sugar chains), trimethylamines and acetate, a decrease in oestradiol concentration, and a further increase in CH(3) groups of lipoproteins and progesterone. The results from the present study showed a clear correlation between the intrafollicular content of alanine and that of oestradiol. A correlation between progesterone and glycoconjugates (sugar chains) was also observed. Therefore, (1)H NMR was shown to be effective for studying specific changes in the biochemical composition of the follicular fluid that occur during follicular development. For the first time, the variation of several compounds (glycoconjugates, lipoproteins, glucose metabolites, amino acids and polyamines) in relation to growth and maturation was demonstrated. Some of these changes could be of crucial importance for follicular maturation and ovulation as well as for oocyte maturation and further fertilization.

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To Analyse the Effect of Relaxation Type on Magnetic Resonance Image Compression Using Compressive Sensing

International Journal of Online and Biomedical Engineering (iJOE) ◽

10.3991/ijoe.v17i04.20759 ◽

2021 ◽

Vol 17 (04) ◽

pp. 21

Author(s):

Vivek Upadhyaya ◽

Mohammad Salim

Keyword(s):

Magnetic Resonance ◽

Compressive Sensing ◽

Magnetic Resonance Image ◽

Similarity Index ◽

Structural Similarity ◽

Scanning Speed ◽

Proton Density ◽

Body Parts ◽

Mr Image ◽

Reconstruction Process

<span>Medical Imaging and scanning technologies are used to provide better resolution of body and tissues. To achieve a better quality Magnetic Resonance (MR) image with a minimum duration of processing time is a tedious task. So our purpose in this paper is to find out a solution that can minimize the reconstruction time of an MRI signal. </span><span>Compressive sensing can be used to accelerate Magnetic Resonance Image (MRI) acquisition by acquiring fewer data through the under-sampling of k-space, so it can be used to minimize the time. But according to the relaxation time, we can further classify the MRI signal into T1, T2, and Proton Density (PD) weighted images. These weighted images represent different signal intensities for different types of tissues and body parts. It also affects the reconstruction process conducted by using the Compressive Sensing Approach. This study is based on finding out the effect of T1, T2, and Proton Density (PD) weighted images on the reconstruction process as well as various image quality parameters like MSE, PSNR, & SSIM also calculated to analyze this effect. Meanwhile, we can analyze how many samples are enough to reconstruct the MR image so the problem associated with time and scanning speed can be reduced up to an extent. In this paper, we got the Structural Similarity Index Measure (SSIM) value up to 0.89 & PSNR value 37.83451 dB at an 85 % compression ratio for the T2 weighted image. </span>

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Nuclear magnetic resonance spectroscopy of bovine ovarian follicular fluid at four selected times of the oestrous cycle

Reproduction Fertility and Development ◽

10.1071/rd06010 ◽

2006 ◽

Vol 18 (5) ◽

pp. 559 ◽

Cited By ~ 5

Author(s):

Gordon E. Sarty ◽

Edward J. Kendall ◽

Gregg P. Adams ◽

Roger A. Pierson

Keyword(s):

Nuclear Magnetic Resonance ◽

Magnetic Resonance ◽

Follicular Fluid ◽

Nmr Spectra ◽

Oestrous Cycle ◽

Physiological Status ◽

Resonance Spectroscopy ◽

Ovarian Follicular Fluid ◽

Time Point ◽

Nuclear Magnetic

The objective of the study was to determine if nuclear magnetic resonance (NMR) spectral features of ovarian follicular fluid were correlated with the physiological status of follicles so that we could assess the feasibility of using NMR spectroscopy during assisted reproduction therapy. Thirty-five sexually mature, nullparious heifers were monitored by transrectal ultrasonography to assess their follicle wave status during the oestrous cycle. Ovariectomies were performed on Day 3 of wave 1 (D3W1, n = 10), Day 6 of wave 1 (D6W1, n = 9), Day 1 of wave 2 (D1W2, n = 9), or in the immediate preovulatory period of at least 17 days after ovulation (D≥17, n = 9). Follicle status was determined to be dominant or subordinate. Follicular fluid was extracted from the follicles and NMR spectra were collected. Principal components were extracted from ratios of line amplitudes and tested for effects of follicle status (dominant v. subordinate) and cycle time point (D1W3, D1W6, D1W2 and D≥17) using multivariate analysis of variance. For most line ratio combinations, main effects of status, time point and their interaction were found (P < 0.05). We concluded that NMR spectra may be used for the determination of ovarian follicle physiological status.

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Acid-base balance parameters of follicular fluid and venous blood in cattle

Acta Veterinaria Brno ◽

10.2754/avb202089010003 ◽

2020 ◽

Vol 89 (1) ◽

pp. 3-10

Author(s):

Eva Indrová ◽

Michaela Andrlikova ◽

Vladislav Bína ◽

Radovan Doležel ◽

Miloslava Lopatářová ◽

...

Keyword(s):

Follicular Fluid ◽

Base Excess ◽

Venous Blood ◽

Follicular Development ◽

Ovarian Activity ◽

Dominant Follicle ◽

Acid Base Balance ◽

Acid Base ◽

Repeated Sampling ◽

Base Balance

The study aimed to compare differences of physiological acid-base balance (ABB) parameters in follicular fluid (FF) and venous blood (VB) and to evaluate ABB parameters in FF collected from different ovarian follicles in dairy cows and heifers. The ABB parameters (pH, pCO2, pO2, HCO3– and base excess (BE)) in the FF of the preovulatory follicle, of the dominant follicle on the 9th day of the cycle and of the superovulatory estrous follicles were compared to VB. Similarly, the dynamics of the ABB profile in FF and VB were monitored in repeated sampling in a group of heifers stimulated by follicle-stimulating hormone (FSH). Higher values of pH and pO2 and lower values of pCO2, HCO3– and BE were found in FF compared to VB in all experiments. Laterality of ovaries, time of sampling, ovarian activity or stimulation of the follicular development by FSH did not significantly influence ABB parameters. We found higher pH (7.392 ± 0.027 vs. 7.364 ± 0.032) and pO2 (13.83 ± 2.20 kPa vs. 4.50 ± 0.67 kPa), lower pCO2 (5.70 ± 0.39 kPa vs. 6.54 ± 0.61 kPa), HCO3– (25.51 ± 1.52 mmol/l vs. 26.86 ± 2.12 mmol/l) and BE (1.14 ± 1.57 mmol/l vs. 1.95 ± 2.2 mmol/l) in FF compared to VB in all non-stimulated cows. Similar relationships between FF and VB were found in all FSH stimulated cows. The study provides as yet unknown knowledge on the physiology of follicular fluid in cattle.

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