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1.
Cytometry A ; 89(5): 480-90, 2016 05.
Article in English | MEDLINE | ID: mdl-27059253

ABSTRACT

The wide possibilities opened by the developments of multi-parametric cytometry are limited by the inadequacy of the classical methods of analysis to the multi-dimensional characteristics of the data. While new computational tools seemed ideally adapted and were applied successfully, their adoption is still low among the flow cytometrists. In the purpose to integrate unsupervised computational tools for the management of multi-stained samples, we investigated their advantages and limits by comparison to manual gating on a typical sample analyzed in immunomonitoring routine. A single tube of PBMC, containing 11 populations characterized by different sizes and stained with 9 fluorescent markers, was used. We investigated the impact of the strategy choice on manual gating variability, an undocumented pitfall of the analysis process, and we identified rules to optimize it. While assessing automatic gating as an alternate, we introduced the Multi-Experiment Viewer software (MeV) and validated it for merging clusters and annotating interactively populations. This procedure allowed the finding of both targeted and unexpected populations. However, the careful examination of computed clusters in standard dot plots revealed some heterogeneity, often below 10%, that was overcome by increasing the number of clusters to be computed. MeV facilitated the identification of populations by displaying both the MFI and the marker signature of the dataset simultaneously. The procedure described here appears fully adapted to manage homogeneously high number of multi-stained samples and allows improving multi-parametric analyses in a way close to the classic approach. © 2016 International Society for Advancement of Cytometry.


Subject(s)
Algorithms , Data Interpretation, Statistical , Flow Cytometry/methods , Immunophenotyping/statistics & numerical data , Leukocytes, Mononuclear/cytology , Cell Lineage/immunology , Fluorescent Dyes/chemistry , Humans , Immunophenotyping/methods , Leukocytes, Mononuclear/classification , Leukocytes, Mononuclear/immunology , Software , Staining and Labeling/methods
2.
Eur J Nutr ; 45(2): 79-87, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16003590

ABSTRACT

BACKGROUND: While a relationship between alcohol and cardiovascular risk factors is well established, data suggest that the type of alcoholic beverage could modulate this relationship. AIM OF THE STUDY: To determine whether drinking patterns modulate the relationship between alcohol and cardiovascular risk factors. METHODS: We tested the relationship between preference of alcoholic beverages and atherosclerotic risk factors in a cross-sectional study of 2,126 men. A hierarchical clustering method determined six drinking patterns, 'low drinkers', 'high quality wines', 'beer and cider', 'digestives', 'local wines', and 'table wines', according to the preferential intake of alcoholic beverages. Logistic models estimated the relative risk of abnormal markers in the drinking patterns compared with low drinkers. Unadjusted estimates investigated the relationship with the cluster as a group, while adjustment on alcohol, nutritional and socio-demographic factors investigated the relationship with the preference of alcoholic beverage in itself. RESULTS: Abstainers had high total plasma homocysteine (tHcy), even after full adjustment (odds ratio (OR) = 1.6, 95% confidence interval (CI): 1.0, 2.8). Drinkers of high quality wine had low lipoprotein( a), high tHcy and high body mass index; beer and cider drinkers had high tHcy and waist circumference. Drinkers of digestives had high triacylglycerol; after adjustment they were at risk of low apolipoprotein A-I (OR = 3.1, 95% CI: 1.2, 7.3), and high tHcy (OR = 4.9, 95% CI: 1.2, 33.3). Local wines drinkers were similar to low drinkers. Table wine drinkers had high apolipoprotein B, high triacylglycerol, and high waist-to-hip ratio. CONCLUSION: Our data suggest that preference of alcoholic beverage could indicate groups at specific risks of atherosclerotic disease.


Subject(s)
Alcohol Drinking , Alcoholic Beverages/classification , Atherosclerosis/epidemiology , Homocysteine/blood , Lipids/blood , Alcohol Drinking/adverse effects , Alcoholic Beverages/analysis , Atherosclerosis/blood , Beer , Body Mass Index , Cluster Analysis , Confidence Intervals , Cross-Sectional Studies , Dose-Response Relationship, Drug , France/epidemiology , Humans , Logistic Models , Male , Middle Aged , Odds Ratio , Risk Factors , Wine
3.
Eur J Nutr ; 44(5): 311-8, 2005 Aug.
Article in English | MEDLINE | ID: mdl-15316829

ABSTRACT

BACKGROUND: Food components of a diet are highly related, so that building up dietary patterns may help understand the relationship between chronic diseases and diet, and identify high risk groups that need preventive advice. AIM: The aim of this study was to determine dietary patterns associated with the colorectal adenoma-carcinoma pathway. METHODS: We performed a two-step analysis using first principal component analysis to select the most appropriate food groups, then a hierarchical agglomerative clustering method, in order to determine dietary patterns in 1372 subjects included in a case-control study. Patients with hyperplastic polyps (n = 103), adenomas < 10 mm, (n = 154) or larger adenomas (n = 208) were then compared with polyp-free controls (n = 426), and colorectal cancer cases (n = 171) compared with population controls (n = 309) using unconditional logistic regression adjusted on age and gender. RESULTS: Cluster analysis determined five food patterns. Cluster 1 identified a low-energy diet; cluster 2 a high-starch, highfat, and low-fruit diet; cluster 3 a high-processed meat, -energy, -alcohol, and -starchy foods diet; cluster 4 a high-fish, -cereals, -honey, -olive oil, -fruit and -vegetables diet; and cluster 5 a high-flour, -sugar, -chocolate, -animal fats, and -eggs diet. Logistic regression identified cluster 2 [corrected] as significantly associated with risk of small adenomas (OR = 1.7; 95% confidence interval 1.0-2.7), large adenomas (OR = 1.9; 1.2-3.0) and cancers (OR = 1.7; 1.1-2.8) compared with cluster 1 [corrected] Cluster 4 diet was inversely associated with risk of small adenomas (OR = 0.4; 0.2-1.0). There was no relationship between patterns and risk of hyperplastic polyps. Multiple adjustment decreased the strength of the relationships with cluster 2 [corrected] which remained significantly associated with adenomas, but not cancer. CONCLUSION: A lowenergy diet appeared as protective all along the adenoma-carcinoma sequence, contrary to a high-energy, high-processed meat and -animal fat diet.


Subject(s)
Adenocarcinoma/epidemiology , Colorectal Neoplasms/epidemiology , Energy Intake/physiology , Feeding Behavior , Adenocarcinoma/etiology , Adenocarcinoma/pathology , Adult , Aged , Case-Control Studies , Cluster Analysis , Colorectal Neoplasms/etiology , Colorectal Neoplasms/pathology , Female , Humans , Logistic Models , Male , Middle Aged , Principal Component Analysis , Risk Factors
4.
J Endocrinol ; 165(2): 207-15, 2000 May.
Article in English | MEDLINE | ID: mdl-10810284

ABSTRACT

We tested the hypotheses that the secretion of dimeric inhibin-A from cultured bovine granulosa cells is stimulated by FSH, and that antral cells secrete more inhibin-A than do mural cells. Cells from the antral or mural compartment of follicles were cultured in defined medium in two culture systems, and dimeric inhibin-A was measured by two-site ELISA or by Western immunoblotting. In the first culture system, dimeric inhibin-A secretion declined with time in culture, but was significantly (P<0.05) higher from antral than from mural cells (as was total inhibin-alpha measured by RIA). The secretion of dimeric inhibin-A and inhibin-alpha from antral but not mural cells was responsive to FSH. In the second culture system, dimeric inhibin-A secretion increased with time in culture, and was significantly stimulated by FSH, but FSH responsiveness was dependent on the concentrations of insulin in the culture medium. The major forms of inhibin-A secreted had molecular masses of approximately 58, 62, 103-116 and >116 kDa; the 32 kDa form was barely detectable. These different forms were all stimulated by FSH, but the >116 and 62 kDa forms were most responsive to FSH. We conclude that (i) FSH stimulates dimeric inhibin-A secretion from bovine granulosa cells, (ii) the 62 kDa form of inhibin-A may be more responsive to FSH than the 58 kDa form, and (iii) the spatial differentiation of granulosa cell function within the follicle previously observed for oestradiol secretion was also observed for inhibin-alpha and dimeric inhibin-A secretion.


Subject(s)
Follicle Stimulating Hormone/pharmacology , Granulosa Cells/metabolism , Inhibins , Peptides/metabolism , Prostatic Secretory Proteins , Animals , Blotting, Western/methods , Cattle , Cells, Cultured , Enzyme-Linked Immunosorbent Assay/methods , Female , Granulosa Cells/drug effects , Molecular Weight , Ovarian Follicle/cytology , Stimulation, Chemical , Time Factors
5.
Mol Reprod Dev ; 54(4): 371-8, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10542377

ABSTRACT

The objective of the present study was to investigate the implication of protein kinase A (PKA), protein kinase C (PKC), and receptor protein tyrosine kinase (R-PTK) pathways in the regulation of estradiol (E2) and progesterone (P4) production by bovine granulosa cells. Cells were harvested from bovine follicles (8-15 mm diameter) and cultured without serum for an initial 3 days (37 degrees C; 5% CO(2) in air; D1-D3). On the fourth day of culture (D4), E2 and P4 production were stimulated with FSH (1-6 ng/ml) or forskolin (FSK) in the presence or absence of intracellular effectors of PKA, PKC, and R-PTK. Culture medium was collected and replaced each day. Stimulation of granulosa cell adenylate cyclase activity with FSK (0.06-3.75 microM) mimicked FSH, inducing a quadratic increase (P < 0.001) of E2 production and a continuous elevation of P4 (P < 0.01). Inhibition of R-PTK activity with genistein (25-50 microM) increased the sensitivity of cells to FSH as demonstrated by a leftward shift in the dose response curve (P < 0.001). Treatment with transforming growth factor-alpha (TGFalpha; 0. 1 ng/ml) abolished the FSH-induced E2 production (P < 0.001) and this effect was not reversed (P < 0.001) by FSK or by genistein. Furthermore, the inhibitory effect of TGFalpha on FSH-induced E2 production was reproduced by phorbol 12-myristate 13-acetate (PMA; 1. 25-2.5 microM), a PKC activator (P < 0.001). Interestingly, genistein inhibited P4 production (P < 0.05). From these results, we conclude that E2 production by bovine granulosa cells is mediated by intracellular factors and can be stimulated downstream from the FSH receptor. The results also suggest that stimulation of R-PTK and/or PKC activities, as probably occurs with TGFalpha, negatively affects the PKA pathway, thus decreasing E2 production. Furthermore, inhibition of R-PTK leads to an increase production of E2 and may limit luteinization of bovine granulosa cells.


Subject(s)
Estradiol/biosynthesis , Granulosa Cells/metabolism , Progesterone/biosynthesis , Protein Kinases/metabolism , Receptors, FSH/metabolism , Adenylyl Cyclases/drug effects , Adenylyl Cyclases/metabolism , Animals , Cattle , Cells, Cultured , Colforsin/pharmacology , Cyclic AMP-Dependent Protein Kinases/metabolism , Dose-Response Relationship, Drug , Enzyme Inhibitors/pharmacology , Female , Genistein/pharmacology , Granulosa Cells/drug effects , Protein Kinase C/drug effects , Protein Kinase C/metabolism , Protein-Tyrosine Kinases/metabolism , Receptor Protein-Tyrosine Kinases/drug effects , Signal Transduction/drug effects , Tetradecanoylphorbol Acetate/pharmacology , Transforming Growth Factor alpha/pharmacology
6.
J Anim Sci ; 76(4): 1172-7, 1998 Apr.
Article in English | MEDLINE | ID: mdl-9581942

ABSTRACT

We studied the effects of active factors present in bovine follicular fluid (bFF) from large healthy or atretic follicles on steroidogenic capability of cultured bovine granulosa cells. Pools of bFF were collected from follicles (> 10 mm; abattoir material) and classified individually as being healthy (bFF-healthy) or atretic (bFF-atretic). Pools of jugular plasma were used as controls and were from heifers bled during the growing (plasma-growing) or the regressing (plasma-regressing) phase of follicular dominance. Granulosa cells were cultured in serum-free conditions and under minimal FSH support (.5 ng/mL) for the first 3 d in order to maintain their physiological estradiol production in response to FSH. Effects of addition of bFF and plasma at final concentrations of 0, 1, or 5% on estradiol and progesterone production and on the percentage of apoptotic cells were determined on d 4 of culture following stimulation of granulosa cells with either 2 or 6 ng/mL FSH. In a parallel experiment, evaluation of 17beta-hydroxysteroid dehydrogenase (17beta-HSD) activity was measured following addition of bFF. In contrast to plasma, addition of bFF pools decreased (P < .001) the FSH-induced estradiol production. Such suppression occurred in a dose-related manner (P < .05) and to a greater extent (P < .001) following addition of bFF from atretic than from healthy follicles. The FSH-induced progesterone production was not affected (P > . 1) by addition of bFF but was stimulated (P < .05) by that of plasma. Follicle-stimulating hormone decreased (P < .001) the percentage of apoptotic granulosa cells and this effect was further enhanced (P < .001) by addition of 1 or 5% bFF. The source of bFF did not affect (P > . 1) the percentage of apoptotic cells measured at the end of the culture period. On d 4, treatment with bFF increased (P < .001) granulosa cell androstenedione conversion into testosterone. Results of the present study indicate that factors contained in bFF can suppress granulosa cell estradiol production, and the suppressive effect varies according to the degree of atresia of the follicle from which the fluid has been harvested.


Subject(s)
Estradiol/biosynthesis , Follicular Atresia/metabolism , Follicular Fluid/physiology , Granulosa Cells/metabolism , Ovarian Follicle/metabolism , Animals , Cattle , Cells, Cultured , Cohort Studies , Dose-Response Relationship, Drug , Female , Follicle Stimulating Hormone/pharmacology , Granulosa Cells/cytology , Ovarian Follicle/cytology
7.
Mol Reprod Dev ; 50(2): 170-7, 1998 Jun.
Article in English | MEDLINE | ID: mdl-9590533

ABSTRACT

This study was undertaken to characterize the relationship between changes in steroid production, cell cycle activity (ie, cell proliferation) and apoptosis in antral and mural bovine granulosa cells cultured in vitro. This was done to select conditions promoting optimal estradiol production by bovine granulosa cells cultured in completely defined conditions. In the first experiment, antral granulosa cells were cultured over the entire 4 days of the culture period in the presence of either 0, 2, or 10 ng/ml of FSH (chronic conditions) or were maintained under minimal FSH support (0.5 ng/ml FSH) for the first 3 days of culture and then were challenged over the fourth day of culture with either 0, 2, or 10 ng/ml FSH (challenged conditions). Compared with cells exposed to constant FSH levels (chronic conditions), the FSH-induced production of estradiol was higher (P < 0.006) and that of progesterone was lower (P < 0.02) over the last 24 h of culture, when antral granulosa cells were maintained under minimal FSH support during the first 3 days of culture (challenged conditions). In the second experiment, dynamics of estradiol and progesterone productions, conversion of [14C]androstenedione into subsequent steroid metabolites, DNA content, cell cycle activity, and apoptosis (as assessed by flow cytometry) of antral and mural granulosa cells over the first 3 days of culture under minimal FSH support and in response to a challenge with FSH during the last 24 h of culture were evaluated. Estradiol production as well as the conversion of androstenedione into testosterone and estradiol were greater (P < 0.01) in antral than in mural granulosa cells cultured under challenged conditions. A higher proportion of mural than antral granulosa cells were in the proliferative state at the end of culture (P < 0.03). This may be related to the decreased ability of mural cells to produce estradiol. FSH suppressed (P < 0.05) the spontaneous onset of apoptosis in both cell types. These results suggest that functional differences between these two cell compartments need to be considered in studying bovine granulosa cells in vitro. Because of their large (400 to 600%) FSH-induced estradiol production, antral granulosa cells cultured under challenged conditions provide a model that can be used to examine substances for their ability to alter estradiol production and apoptosis in bovine granulosa cells.


Subject(s)
Estradiol/biosynthesis , Follicle Stimulating Hormone/pharmacology , Granulosa Cells/metabolism , Animals , Apoptosis , Cattle , Cell Division , Cells, Cultured , Female , Granulosa Cells/drug effects , Models, Biological , Steroids/biosynthesis
8.
Biol Reprod ; 57(2): 341-6, 1997 Aug.
Article in English | MEDLINE | ID: mdl-9241048

ABSTRACT

Growth factors such as transforming growth factors alpha (TGF alpha) and beta (TGFbeta) secreted by theca cells and present in bovine follicular fluid (bFF) have been implicated in granulosa cell growth and differentiation. We investigated these phenomena using two complementary approaches to evaluate the physiological contribution of TGF alpha and TGFbeta in the control of the FSH-induced estradiol production in bovine granulosa cells from large follicles. Granulosa cells (3 x 10(5) viable cells/cm2) harvested from eCG-treated prepubertal calves were cultured (serum free) in wells containing 500 microl/cm2 of defined Ham's F-12 medium supplemented with 0.5 ng/ml FSH for the first 3 days (37 degrees C; 95% air:5% CO2). In the first approach, the effects of individual addition of TGF alpha and TGFbeta at final concentrations of 1 x 10(-4) to 10 ng/ml were determined on Day 4 of culture after stimulation of granulosa cell estradiol production with 6 ng/ml FSH. In a second approach, TGF alpha or TGFbeta was removed specifically from bFF (from large follicles > 10 mm) by immunoneutralization. Thereafter, effects of immunoneutralization of TGF alpha or TGFbeta (0, 0.1, 1, 10, and 100 microg/ml anti-TGF neutralizing antibody) present in bFF (2%) were determined on Day 4 of culture following stimulation of granulosa cell estradiol production with 6 ng/ml FSH. On Day 4, FSH increased (p < 0.001) granulosa cell estradiol production (0 vs. 6 ng/ml FSH). Addition of TGF alpha decreased the granulosa cell estradiol production after 6 ng/ml FSH stimulation in a dose-dependent manner (p < 0.001). In contrast, addition of TGFbeta had no effect on the granulosa cell estradiol production (p > 0.1) after the addition of 6 ng/ml FSH. Addition of bFF (2%) decreased (p < 0.0001) the FSH-induced estradiol production by bovine granulosa cells. After immunoneutralization of TGF alpha in bFF, however, this suppressed FSH-induced estradiol production was restored to levels obtained in the absence of bFF, and this occurred in a dose-dependent manner (p < 0.05). Immunoneutralization of TGFbeta in bFF did not prevent (p > 0.1) the suppressive effect of bFF on FSH-induced estradiol production. These results suggest that TGF alpha produced in vivo by large bovine follicles can act locally (auto/paracrine manner) to suppress granulosa cell estradiol production.


Subject(s)
Estradiol/biosynthesis , Follicle Stimulating Hormone/pharmacology , Follicular Fluid/metabolism , Granulosa Cells/metabolism , Transforming Growth Factor alpha/physiology , Animals , Antibodies/pharmacology , Apoptosis , Cattle , Cell Division , Cells, Cultured , Female , Humans , Transforming Growth Factor alpha/immunology , Transforming Growth Factor alpha/pharmacology , Transforming Growth Factor beta/pharmacology , Transforming Growth Factor beta/physiology
9.
J Anim Sci ; 74(12): 3012-9, 1996 Dec.
Article in English | MEDLINE | ID: mdl-8994916

ABSTRACT

Functional subpopulations of granulosa cells exist in bovine follicles. This study was designed to compare the in vitro steroid production by cultured bovine antral and mural granulosa cells in response to various amounts of FSH. Antral and mural granulosa cells (600,000 viable cells/well) harvested from ovaries of PMSG-treated prepuberal calves were cultured in serum-free conditions for 4 d in wells containing 1 mL of defined Ham's F-12 medium, supplemented with 0, 2, or 10 ng/mL of FSH. Culture medium was collected and replaced each day. The mean concentration of estradiol in culture media of bovine granulosa cells decreased from d 1 to d 4 (P < .001). Granulosa cell production of estradiol increased in antral cells following addition of 2 ng/mL FSH (P < .001) but decreased following addition of 10 ng/mL FSH (P < .001) as determined on d 4 by RIA and thin layer chromatography. In contrast, there was no response to FSH stimulation in mural granulosa cells. Progesterone production increased (P < .01) in a dose-dependent manner following stimulation with 2 or 10 ng/mL FSH and was consistently higher (P < .001) in antral than in mural granulosa cells. Addition of LH on d 4 stimulated estradiol and progesterone production in antral (P < .01) but not in mural cells (P > .10). This suggests that FSH- and LH-induced estradiol and progesterone productions are considerably lower in mural than in antral bovine granulosa cells. This suggests that functional differences between these two cell compartments need to be considered in studies involving in vitro cultures of bovine granulosa cells.


Subject(s)
Culture Media/pharmacology , Estradiol/metabolism , Follicle Stimulating Hormone/pharmacology , Granulosa Cells/cytology , Granulosa Cells/metabolism , Progesterone/metabolism , Androstenedione/metabolism , Animals , Cattle , Cells, Cultured , Chromatography, Thin Layer/veterinary , Culture Media/analysis , DNA/analysis , DNA/metabolism , Dose-Response Relationship, Drug , Female , Granulosa Cells/chemistry , In Vitro Techniques , Luteinizing Hormone/pharmacology , Radioimmunoassay/veterinary
10.
Theriogenology ; 46(6): 1053-61, 1996 Oct 15.
Article in English | MEDLINE | ID: mdl-16727969

ABSTRACT

This study was designed to determine the effect of the presence of a dominant follicle at the beginning of FSH stimulation on the morphological appearance and functional capacity of recruited follicles during FSH stimulation in cattle. Synchronized nonlactating dairy cows were assigned to 1 of 2 groups and treated with FSH in the presence (n = 5) or absence (n = 6) of a dominant follicle between Days 7 and 12 of the estrous cycle (Day 0 = estrus) to stimulate follicular growth. Dominant follicles were identified by daily ultrasonographic observations, beginning on Day 3 of the estrous cycle. Dominant follicle had an ultrasonographic diameter > or = 10 mm and were in a growing phase, or maintaining a constant diameter (> or = 10 mm) for less than 4 d. Ovaries were collected at slaughter on the morning of the third day following initiation of the FSH stimulation. All follicles > 2 mm were dissected, classified according to diameter (Class 1: 2 to 4.4 mm; Class 2: 4.5 to 7.9 mm; Class 3: > 8 mm), and incubated individually for 90 min in medium M-199 (37 degrees C, 5% CO2). Following incubation, integrity of each follicle was evaluated histologically to assess the level of atresia and biochemically to determine the in vitro release of estradiol (E2) and androstenedione in culture media. On Day 3 of the FSH treatment, mean number of follicles in each class was similar (P > 0.1) between the 2 groups. The percentage of atretic follicles in Classes 1 and 3 on Day 3 of the FSH stimulation did not differ (P > 0.1) between the 2 groups. However, the percentage of atretic follicles in Class 2 was higher (P < 0.005) in cows treated with FSH in presence than in absence of a dominant follicle (60.8 vs 38.2%). The release of E2 in culture media by small Class 1 atretic or healthy follicles, by Class 2 atretic and by Class 3 healthy follicles was not affected (P > 0.1) by the ovarian status. However (P < 0.001), the release of E2 in culture media of Class 2 healthy and Class 3 atretic follicles was less for follicles harvested from cows bearing than from those not bearing a dominant follicle. Within each follicular class, concentrations of androstenedione in the culture media did not differ between the 2 groups (P > 0.1). These results suggest that the presence of a dominant follicle at the beginning of FSH stimulation alters the population of follicles recruited FSH stimulation. This may be associated with the reported decrease of the superovulatory response in cows superovulated in presence of a dominant follicle.

11.
Biol Reprod ; 48(2): 268-76, 1993 Feb.
Article in English | MEDLINE | ID: mdl-8439616

ABSTRACT

The objectives were to determine the relationships between changes in the levels of histological and biochemical (estradiol [E2]:androstenedione [A], E2:A ratio) atresia and changes in inhibin contents of morphologically dominant follicles collected during the growing or the regressing phase of the first wave of follicular development in cycling crossbred beef heifers. Heifers were slaughtered either when the dominant follicle (> or = 9 mm; diameter of the antral cavity as assessed by ultrasonography) of the first wave was still growing (n = 7) or when the first dominant follicle (> or = 9 mm; n = 7) was regressing or was at the end of the plateau phase. Following ovary collection, the dominant follicle was dissected and level of histological atresia was determined on sections of follicular walls. Aliquots of follicular fluid from each of the dominant follicles were collected to measure concentrations of E2, A, and inhibin alpha subunit by RIA and to measure concentrations of dimeric (alpha-beta dimer) inhibin by a two-site immunoradiometric assay. Heifers were slaughtered on Days 5.4 +/- 0.5 (growing phase) and 11.8 +/- 0.5 (regressing phase) of the estrous cycle, and mean diameter of the dominant follicles was similar in both phases (9.9 +/- 0.4 vs. 10.8 +/- 0.4 mm; p > 0.09). All morphologically dominant follicles collected during the growing phase (7/7) were histologically healthy and estrogen-active (E2:A ratio > 1), while those collected during the regressing phase (7/7) were histologically atretic and estrogen-inactive (E2:A ratio < 1; chi 2 = 14.0, p < 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Cattle/physiology , Estrus/physiology , Follicular Atresia/metabolism , Follicular Fluid/chemistry , Inhibins/biosynthesis , Analysis of Variance , Androstenedione/biosynthesis , Animals , Estradiol/biosynthesis , Female , Ovarian Follicle/anatomy & histology , Ovarian Follicle/physiology , Radioimmunoassay
12.
Can Vet J ; 32(2): 91-3, 1991 Feb.
Article in English | MEDLINE | ID: mdl-17423745
13.
J Reprod Fertil ; 91(1): 81-9, 1991 Jan.
Article in English | MEDLINE | ID: mdl-1995865

ABSTRACT

Dairy heifers were superovulated in the presence (dominant group, N = 8) or absence (non-dominant group, N = 6) of a dominant follicle at the start of a a superovulatory treatment on Days 7-12 of the oestrous cycle (Day 0 = oestrus). Daily ultrasonographic observations of ovaries (recorded on videotape) starting on Day 3 were used to assess the presence or absence of a dominant follicle (diameter greater than 9 mm, in a growing phase or at a stable diameter for less than 4 days) and to monitor follicular development before and during treatment. The number of CL estimated by ultrasonography (7.1 +/- 1.8 vs 13.5 +/- 1.4) or by rectal palpation (6.9 +/- 2.0 vs 16.3 +/- 1.6) and mean progesterone concentrations (32.5 +/- 19 vs 80.7 +/- 16 ng/ml) after treatment were lower (P less than 0.01) in the dominant than in the non-dominant group. Based on number of CL, two populations of heifers were identified in the dominant group, i.e. those that had a high (dominant-high, N = 4; greater than 7 CL) or a low (dominant-low, N = 4; less than 7 CL) response to treatment. During treatment, the increases in number of follicles 7-10 mm and greater than 10 mm in diameter occurred sooner and were of higher magnitude in the non-dominant than in the dominant-high or dominant-low groups (P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Cattle/physiology , Ovarian Follicle/physiology , Superovulation/physiology , Animals , Corpus Luteum/diagnostic imaging , Corpus Luteum/physiology , Female , Ovarian Follicle/diagnostic imaging , Ovarian Follicle/growth & development , Progesterone/blood , Ultrasonography
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