Size distribution and meiotic competence of oocytes obtained from bitch ovaries at various stages of the oestrous cycle

2001 ◽  
Vol 13 (3) ◽  
pp. 151 ◽  
Author(s):  
Takeshige Otoi ◽  
Aya Ooka ◽  
Masako Murakami ◽  
N.W. Kurniani Karja ◽  
Tatsuyuki Suzuki
Keyword(s):  
Size Distribution ◽  
Relative Size ◽  
Follicular Phase ◽  
Oestrous Cycle ◽  
The Other ◽  
Three Stages ◽  
The Mean ◽  
The Relationship ◽  
Meiotic Competence

The present study was conducted to examine the effects of the stage of the oestrous cycle on the meiotic competence of canine oocytes and also to investigate the relationship between the stage of the oestrous cycle and the relative size distribution of oocytes obtained from bitches at three stages of the cycle (anoestrus, follicular phase and dioestrus). Only healthy-looking cumulus–oocyte complexes were used for in vitro maturation and these were divided into three groups based on diameter (<110, 110 to <120 and ≥120 µm). The mean diameter of oocytes from ovaries at anoestrus, the follicular phase and dioestrus was 103.6, 119.2 and 107.7 µm, respectively. The percentage of large oocytes (120 µm) collected at the follicular phase was higher (P<0.01) than that collected at dioestrus and the percentage of oocytes ≥120 µm collected from ovaries at dioestrus was higher (P<0.01) than that collected at anoestrus. After culture for 72 h, significantly more oocytes reached metaphase II (MII) in the follicular phase than in the other stages (P<0.01), and more oocytes reached MII in dioestrus than in anoestrus (P<0.05). In the ≥120 µm group, the frequency of oocytes that resumed meiosis in the follicular phase was higher (P<0.05) than in the other stages. However, in the smaller diameter (<120 µm) groups, there were no significant differences between ovaries at different stages of the oestrous cycle with respect to the proportion of oocytes reaching each stage of meiosis. Thus, the oestrous cycle stage influences maturation frequency. Moreover, oocytes demonstrated a size-related ability to undergo meiotic maturation, irrespective of the stage of the oestrous cycle. These results suggest that the effects of the stage of the oestrous cycle may result from differences in the distribution of large oocytes.

scholarly journals Oestrous cycle stage influences the morphology and maturation of porcine oocytes in vitro

2008 ◽  
Vol 53 (No. 2) ◽  
pp. 70-76 ◽  
Author(s):  
M. Machatkova ◽  
P. Hulinska ◽  
J. Horakova ◽  
Z. Reckova ◽  
K. Hanzalova
Keyword(s):  
Follicular Development ◽  
Cumulus Cells ◽  
Follicular Phase ◽  
Oestrous Cycle ◽  
Porcine Oocyte ◽  
The Mean ◽  
Oocyte Donors ◽  
Meiotic Competence ◽  
Late Follicular Phase

The objective of the study was to characterize the effect of the oestrous cycle stage on the yield, morphology and meiotic competence of porcine oocytes. A total of 46 cycling gilts, at 8.5–9 months of age, were used as oocyte donors. Their oestrous cycle was synchronized by Regumate and the onset of oestrus was checked (Day 0). The gilts were slaughtered at the early (Days 1–5), middle (6–10) and late (11–14) luteal or early (Days 15–16), middle (17–19) and late (20–21) follicular phase. Oocytes were isolated separately from medium (5–9 mm) and small (≤ 4 mm) follicles. Cumulus-oocyte complexes with dark, evenly granulated cytoplasm and at least two compact layers of cumulus cells were selected as useful for maturation. They were matured by a standard protocol, denuded from cumulus cells, fixed in glutaraldehyde, stained with 33258-Hoechst and examined by epifluorescence. The oocytes collected from small and medium follicles differed in their yield, morphology and meiotic competence regardless of the phase. The mean number (± S.E.M.) of oocytes isolated per donor was higher (187.7 ± 48.4 vs. 16.9 ± 6.1) but the mean percentage (± S.E.M.) of useful oocytes was lower (22.4 ± 7.5% vs. 80.2 ± 6.8%; <I>P</I> < 0.01) for small than for medium follicles. The mean number (± S.E.M.) of useful oocytes per donor was significantly (<I>P</I> < 0.01) higher (42.1 ± 16.8 vs. 11.9 ± 4.3) but the mean percentage of matured oocytes was significantly (<I>P</I> < 0.01) lower (48.4 ± 17.8% vs. 79.9 ± 7.9%) for small than for medium follicles. The oocyte population collected from small follicles varied during the oestrous cycle. The mean number (± S.E.M.) of oocytes isolated per donor from small follicles increased during the luteal and decreased during the follicular phase, except for the late follicular phase when it increased again. The mean percentage (± S.E.M.) of useful oocytes did not differ too much during this period, except for the late follicular phase when it decreased significantly (<I>P</I> < 0.01). The mean number (± S.E.M.) of useful oocytes per donor increased during the luteal and decreased during the follicular phase, but the differences were not significant except for the late follicular phase (<I>P</I> < 0.01). Similarly, the mean percentage (± S.E.M.) of matured oocytes increased during the luteal and decreased during the follicular phase, and the differences were significant. Compared with the oocyte population from small follicles, the oocyte population from medium follicles was less variable in the period from the middle luteal to middle follicular phase, when these follicles were present on the ovaries. It can be concluded that the porcine oocyte population changes in terms of quantity, morphological quality and meiotic competence according to the stage of follicular development. The late luteal and early follicular phases appeared to be most productive for oocyte recovery, because more morphologically normal oocytes with greater meiotic competence were collected, as compared with the other stages of the oestrous cycle.

An in vitro Evaluation of Artificial Caries-like Lesions on Restored Overdenture Abutments

1988 ◽  
Vol 67 (3) ◽  
pp. 582-584 ◽  
Author(s):  
P.P. Kambhu ◽  
R.L. Ettinger ◽  
J.S. Wefel
Keyword(s):  
Light Microscopy ◽  
Polarized Light ◽  
Polarized Light Microscopy ◽  
The Other ◽  
Type Ii ◽  
Restorative Materials ◽  
Abutment Teeth ◽  
The Mean ◽  
Materials Used

An acidified dialyzed gelatin gel system was used to determine the caries resistance of a variety of restorative materials used to obturate the canal orifice of overdenture abutment teeth. The restorative materials used were Tytin, Tytin + Copalite, P30 + Scotchbond, Fuji Ionomer-Type II, and Miracle Mix. Polarized light microscopy and microradiography were used to examine the caries-like lesions adjacent to the restorations. The lesions formed in the Fuji Ionomer-Type II and Miracle Mix groups appeared arrested at the wall adjacent to the restoration, and did not penetrate apically down the wall as did those associated with the other restorative materials. The mean depths of lesions adjacent to Fuji Ionomer-Type II and Miracle Mix restorations were significantly less than those of Tytin, Tytin + Copalite, or P30 + Scotchbond.

STUDIES ON THE IN VITRO PRODUCTION OF CORTICOSTEROIDS BY ADRENAL GLANDS FROM NORMOTENSIVE INDIVIDUALS AND HYPERTENSIVE PATIENTS

1962 ◽  
Vol 40 (1) ◽  
pp. 285-301 ◽  
Author(s):  
Jean Davignon ◽  
Erich Koiw ◽  
Wojciech Nowaczynski ◽  
Gilles Tremblay ◽  
Jacques Genest
Keyword(s):  
Cushing’S Syndrome ◽  
Adrenal Glands ◽  
Cushing's Syndrome ◽  
The Other ◽  
Malignant Hypertension ◽  
Unit Weight ◽  
Chromatographic Technique ◽  
Acth Stimulation ◽  
The Mean

The production of aldosterone and other corticosteroids by adrenal glands surgically removed from 5 normotensive subjects with renal disease of various types, 11 patients with arterial hypertension, and 2 with Cushing's syndrome was investigated in vitro by the incubation chromatographic technique. The rate of steroid formation per unit weight of tissue was markedly lower in severe and malignant hypertension and slightly higher in benign hypertension as compared with the rate in normotensive controls. The amount of steroid released varied widely from one gland to the other and showed marked overlapping between the various groups; these variations were most prominent in benign hypertension, less in the normotensive group, and least evident in severe and malignant hypertension. The response of steroidogenesis to ACTH stimulation in vitro was slightly reduced in severe and malignant hypertension. The mean output of aldosterone by adrenal glands from hypertensives was slightly above the mean value obtained with normotensive control glands. The percentage of aldosterone formation in respect to total steroid production was roughly correlated with the severity of hypertension. In four hyperplastic adrenals obtained from two cases of Cushing's syndrome, the in vitro formation of steroids per unit weight of tissue and the response to ACTH did not differ significantly from that found in glands obtained from the other patients under study. The value of in vitro studies for the assessment of the functional capacity of the adrenal cortex is discussed.

scholarly journals Inhibition of Demineralization at Restoration Margins of Z100 and Tetric EvoCeram Bulk Fill in Dentin and Enamel

2019 ◽  
Vol 6 (2) ◽  
pp. 36
Author(s):  
Cristina Leon-Pineda ◽  
Kevin Donly
Keyword(s):  
Light Microscopy ◽  
Polarized Light ◽  
In Vitro Study ◽  
The Other ◽  
Solution Ph ◽  
Class V ◽  
The Mean ◽  
Student’S T ◽  
Student’S T Test

Recurrent caries is still considered the main reason restorations need to be replaced. There are different materials available now that promise to reduce the possibility of recurrent caries by releasing fluoride and inhibiting restoration marginal caries. The purpose of this in vitro study was to evaluate the demineralization inhibition potential of a non-fluoride-releasing resin (Z100TM 3M, St. Paul, MN, USA) and a glass containing resin-based composite (Tetric EvoCeram Bulk Fill, Ivoclar/Vivadent AG, Schaan, Liechtenstein), which contains fluoride. Class V preparations were placed on 22 premolars; the gingival margin was below the cementoenamel junction and the occlusal margin was placed above the cemento-enamel junction. Ten teeth were randomly selected to be restored with Z100 while the other 10 were restored with Tetric EvoCeram Bulk Fill. Both groups were restored following manufacturer’s instructions. All teeth had an acid resistant varnish placed within one millimeter of the preparation margins. Both groups were placed in artificial caries challenge solution (pH 4.4). At the end of the 4 days; 100 µm buccolingual sections were obtained for each tooth; these were photographed under polarized light microscopy and the demineralized areas adjacent to the restorations were measured and quantified. The mean (±S.D.) area (µm2) of demineralization from the occlusal margin (enamel) and dentin margin were: Z100 2781.889 ± 1045.213; 3960.455 ± 705.964 and for Tetric EvoCeram Bulk Fill 1541.545 ± 1167.027; 3027.600 ± 512.078. Student’s t-test indicated that there was significantly less enamel and dentin demineralization adjacent to Tetric EvoCeram Bulk Fill compared to Z100; there was significantly less demineralization in enamel compared to dentin in both Tetric EvoCeral Bulk Fill and Z100. Tetric EvoCeram Bulk Fill performed better inhibiting demineralization at restoration margins when compared to Z100 and provided better demineralization inhibition in enamel than cementum/dentin.

The Effect of Waking Suggestion on Post-Hypnotic Amnesia

1981 ◽  
Vol 11 (1) ◽  
pp. 44-46 ◽  
Author(s):  
D.P. Fourie
Keyword(s):  
Point Of View ◽  
The Other ◽  
Hypnotic Susceptibility ◽  
The Subject ◽  
The Mean ◽  
The Difference ◽  
The One ◽  
The Relationship ◽  
Female Subjects

It is increasingly realized that hypnosis may be seen from an interpersonal point of view, meaning that it forms part of the relationship between the hypnotist and the subject. From this premise it follows that what goes on in the relationship prior to hypnosis probably has an influence on the hypnosis. Certain of these prior occurences can then be seen as waking suggestionns (however implicitly given) that the subject should behave in a certain way with regard to the subsequent hypnosis. A study was conducted to test the hypothesis that waking suggestions regarding post-hypnotic amnesia are effective. Eighteen female subjects were randomly divided into two groups. The groups listened to a tape-recorded talk on hypnosis in which for the one group amnesia for the subsequent hypnotic experience and for the other group no such amnesia was suggested. Thereafter the Stanford Hypnotic Susceptibility Scale was administered to all subjects. Only the interrogation part of the amnesia item of the scale was administered. The subjects to whom post-hypnotic amnesia was suggested tended to score lower on the amnesia item than the other subjects, as was expected, but the difference between the mean amnesia scores of the two groups was not significant.

Philosophy and Common Sense

Philosophy ◽  
1988 ◽  
Vol 63 (244) ◽  
pp. 161-174 ◽  
Author(s):  
Keith Campbell
Keyword(s):  
Twentieth Century ◽  
Common Sense ◽  
Large Scale ◽  
Natural Philosophy ◽  
The Other ◽  
Jerry Fodor ◽  
Rational Acceptability ◽  
Three Stages ◽  
The One ◽  
The Relationship

This paper raises once more the question of the relationship between philosophy on the one hand and common sense on the other. More particularly, it is concerned with the role which common sense can play in passing judgment on the rational acceptability (or otherwise) of large-scale hypotheses in natural philosophy and the cosmological part of metaphysics. There are, as I see it, three stages through which the relationship has passed in the course of the twentieth century. There is the era of G. E. Moore, the Quine–Feyerabend period, and now a new and modest vindication of common sense is emerging in the work of Jerry Fodor.

Effect of Different Intermediary Bases on Microleakage of a Restorative Material in Class II Box Cavities of Primary Teeth

2017 ◽  
Vol 40 (2) ◽  
pp. 82-87 ◽  
Author(s):  
Faika Y. Abdelmegid ◽  
Fouad S. Salama ◽  
Waleed M. Al-Mutairi ◽  
Saud K. Al-Mutairi ◽  
Sultan O. Baghazal
Keyword(s):  
Primary Teeth ◽  
In Vitro Study ◽  
Class Ii ◽  
Positive Control ◽  
Negative Control ◽  
The Other ◽  
Control Groups ◽  
Significant Difference ◽  
The Mean

Introduction The aim of this in vitro study was to assess and compare the effect of different intermediary bases on microleakage between tooth and a nanocomposite interface in Class II box cavities in primary teeth. Methods Standard Class II box cavities were prepared in 52 primary molars and randomly divided into 9 groups according to the intermediary base used (Multicore Flow, Fuji II LC, SDR, Smart Dentin Replacement, and Biodentine). All specimens were subjected to thermocycling and prepared for microleakage testing and evaluation. Results There was significant difference in the mean ranks of microleakage between the 9 groups, which was observed in the gingival side (p<0.0001) and the occlusal side (p<0.0001). The mean ranks microleakage was significantly higher with experimental SDR, experimental Multicore Flow, and positive control materials when compared with the other 6 groups. The microleakage mean ranks were statistically significantly lower in experimental Fuji II LC, experimental Biodentine, and all negative control groups when compared with the other 3 groups. Conclusions Microleakage is affected by the application of intermediate material. Experimental Biodentine and Fuji II LC showed the lowest microleakage while experimental SDR and experimental Multicore Flow showed the highest microleakage.

OBSERVATIONS ON SUCCESSIVE PRO-OESTROUS LH SURGES IN INDIVIDUAL 4-DAY CYCLING AND POST-PSEUDOPREGNANT RATS

1978 ◽  
Vol 88 (2) ◽  
pp. 274-284 ◽  
Author(s):  
Alberto J. Carrillo ◽  
Charles H. Sawyer
Keyword(s):  
Mechanical Stimulation ◽  
Term Effect ◽  
Oestrous Cycle ◽  
The Other ◽  
Peak Amplitude ◽  
Lh Surge ◽  
Long Term Effect ◽  
The Mean ◽  
Stimulation Of

ABSTRACT The internal variations (i. e. in timing, duration and amplitude) of the LH surge mechanism within individual rats were examined by monitoring from 3 to 7 successive pro-oestrous LH surges in each of 5 regular 4-day cycling rats fitted with chronic intravenous cannulas. On each successive pro-oestrus blood was collected (0.5–0.6 ml hourly from 14.00–21.00) for radioimmunoassay of LH. The surgery of cannulation had no long-term effect on the regularity of the oestrous cycle. Two rats did, however, show briefly irregular cycles, including one with a 9-day period of anoestrus (pseudopregnancy). In three of the five rats successive pro-oestrous plasma LH curves (4 in one and 3 each in the other two) were internally very consistent in timing, shape and amplitude, However, between each 2 of these 3 animals there were distinct differences in the LH secretory patterns, by as much as 2 h in timing of the onset of the surge and its peak amplitude. The first two surges of the other two rats were atypical of their subsequent surges, which were mostly consistent in timing and amplitude. The pro-oestrous LH surge following the 9-day period of anoestrus was advanced by 2 h and elevated to twice the mean peak amplitude of the cyclic LH surges in that rat. Subsequently, post-PSP surges were studied in rats made pseudopregnant by mechanical stimulation of the cervix. In all cases the immediate post-PSP surge occurred earlier in the afternoon and with a greater peak amplitude than the subsequent cyclic LH surge in the same rat.

OESTROGEN SYNTHESIS IN RAT OVARIES IN VITRO: EFFECTS OF ENDOGENOUS AND EXOGENOUS GONADOTROPHINS

1972 ◽  
Vol 53 (3) ◽  
pp. 397-406 ◽  
Author(s):  
BRENDA ROBINSON ◽  
R. E. OAKEY
Keyword(s):  
Luteinizing Hormone ◽  
Follicle Stimulating Hormone ◽  
Oestrous Cycle ◽  
The Other ◽  
Ovarian Vein ◽  
Hormone Activity ◽  
In Vitro Effects ◽  
Stimulating Hormone

SUMMARY The rate of synthesis of [14C]oestrone and [14C]oestradiol-17β from [14C]testosterone in vitro by ovaries from rats at different stages of the oestrous cycle was measured. The rate of [14C]oestrogen synthesis was highest in ovaries taken from rats in pro-oestrus and lowest in ovaries taken from rats early in the dioestrous phase of the cycle. Rates of synthesis in ovaries obtained from rats in the late dioestrous stage were intermediate between the rates of the other groups. The rates of [14C]oestrogen synthesis at these periods of the cycle paralleled the concentrations of oestrogens in ovarian vein plasma reported by other authors. Gonadotrophin preparations with either luteinizing hormone activity or both follicle-stimulating hormone and luteinizing hormone activities had no effect on [14C]oestrogen synthesis by rat ovaries in vitro at any of these stages of the oestrous cycle.

The Effect of Casein Phosphopeptide-Amorf Calcium Phosphate and Acidulated Phosphate Fluoride Gel on Dental Erosion in Primary Teeth: An in Vitro Study

2017 ◽  
Vol 41 (4) ◽  
pp. 275-279 ◽  
Author(s):  
Eda Arat Maden ◽  
Özge Acar ◽  
Ceyhan Altun ◽  
Günseli Güven Polat
Keyword(s):  
Surface Roughness ◽  
Protective Effect ◽  
Primary Teeth ◽  
Artificial Saliva ◽  
Soft Drink ◽  
Dental Erosion ◽  
The Other ◽  
The Mean ◽  
Casein Phosphopeptide

Objective: This study aimed to investigate the effect of acidulated phosphate fluoride (APF) gel and casein phosphopeptide/amorphous calciumphosphate (CPP-ACP) on the dental erosion produced by carbonated soft drink in primary teeth. Study Design: This study evaluated by an in vitro model the effect of APF gel and CPP-ACP on the dental enamel previously subjected to erosive challenge with carbonated soft drink. Sixty sound human primary molars were prepared by embedding the crown sections in acrylic resin blocks leaving the enamel surfaces exposed. The surface roughness of the enamel was measured with prophilometry at baseline. Specimens were randomly divided into three treatment groups (n:20): artificial saliva, CPP-ACP, 1.23% APF gel. All specimens were then exposed to an erosive challenge of carbonated soft drink and artificial saliva for 20 cycles of 20 seconds each. Demineralization-remineralization cycles was repeated twice at eight-hour intervals and roughness values were measured. Enamel samples were treated with artificial saliva, CPP-ACP, 1.23% APF gel applied for 10 min after erosive challenge. The arithmetic average roughness (Ra) readings were recorded after remineralization agents were applied. Results: The mean surface roughness in all groups increased significantly after erosion process and decreased after remineralization treatment. After treatment, the mean surface roughness of the 1.23% APF gel group was significantly less than the other groups and the mean surface roughness of the artificial saliva group was significantly more than the other groups. 1.23% APF gel showed the highest protective effect against erosive enamel loss. Conclusions: Under the conditions of this study, artificial saliva, CPP-ACP and 1.23% APF treatments were able to reduce erosive enamel loss produced by carbonated soft drink in primary teeth. However, 1.23% APF gel showed the highest protective effect against erosive enamel loss.

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