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M T Kane

Publications and source records attributed to M T Kane.

16 recordsLinked to original sources

Inositol stimulates DNA and protein synthesis, and expansion by rabbit blastocysts in vitro.

The effect of different concentrations (0, 0.6, 3, 15, 75 and 375 microM) of myo-inositol on the development of rabbit morulae to expanded blastocysts was investigated in terms of blastocyst expansion and synthesis of DNA and protein, as measured by incorporation of [3H]thymidine and [14C]amino acids into acid-precipitable material. A concentration of 15 microM inositol caused a 2.8-fold increase in blastocyst expansion (P less than 0.01), a 9.9-fold increase in thymidine incorporation into DNA (P less than 0.01) and a 3.6-fold increase in amino acid incorporation into protein (P less than 0.01). There were no significant differences in the range from 15 to 375 microM inositol.

Animals

Purification of an embryotrophic factor from commercial bovine serum albumin and its identification as citrate.

A factor of low M(r) with growth-promoting effects on rabbit embryos was extracted and purified from commercial bovine serum albumin (BSA). This embryotrophic factor was extracted from BSA dissolved in formic acid by membrane filtration (membrane cutoff of M(r) 10,000) and then freeze-drying of the filtrate. The extract was purified successively by chromatography on G-10 Sephadex, QAE-Sephadex A-25 anion exchange and high-performance liquid chromatography (HPLC) reverse-phase columns. Mass spectrometry of the active reverse-phase material indicated that the major component in this material had an M(r) of 192. The embryotrophic factor in the low M(r) extract of BSA was shown to be citrate, because: (i) the mass spectra of the active reverse-phase material and citrate were identical, (ii) the activity was eluted at the identical position to citrate on an analytical HPLC anion-exchange column, (iii) the original BSA sample was shown by enzyme assay to be heavily contaminated by citrate and (iv) citrate stimulated cell proliferation and expansion of blastocysts.

Animals

Uptake and incorporation of inositol by preimplantation mouse embryos.

The uptake of myo-inositol by preimplantation mouse embryos was investigated using [3H]myo-inositol. Uptake increased about 12-fold between one- and two-cell stages and increased again at the blastocyst stage (> 6-fold compared with the two-cell stage). Uptake at the blastocyst stage was time and temperature dependent; it was stimulated by sodium, inhibited by glucose and appeared to take place mainly via a saturable mechanism. Uptake in the presence of 6.25 mmol inositol l-1 was 1424 fmol inositol per blastocyst per h. About 10% of the [3H]inositol taken up by blastocysts during 8 h in culture was incorporated into lipid. Thin layer chromatography of the lipid showed that most of this inositol was incorporated into lipid material co-migrating with phosphatidylinositol with a small proportion co-migrating with phosphatidylinositol 4-phosphate.

Analysis of Variance

Control of growth in preimplantation embryos.

I would like to thank the President and the Selection Committee of the Academy for the honour of an invitation to present the 1990 Conway Review Lecture. The subject of the topic is the Control of Growth in Preimplantation Embryos.

Animals

Successful co-culture of 1-4-cell cattle ova to the morula or blastocyst stage.

Bovine ova (n = 326) collected at the 1-4-cell stage were cultured in TCM-199 + 10% foetal calf serum with or without oviducal cells. The bovine oviducal cells were collected and seeded either on the day of ovum recovery (BOC-0) or 3 days earlier (BOC-3). In Exp. 1, the effect of age of oviducal cells in co-culture on ovum development was examined. In the BOC-0 and BOC-3 treatments, respectively, 36/46 (78%) and 30/37 (81%) of ova developed to morulae or blastocysts, while no ova developed past the 8-16-cell stage in the absence of oviducal cells. In Exp. 2, the effect of age of oviducal cells and of physical contact between the oviducal cells and ova on ovum development was examined. In the BOC-0 and BOC-3 treatments, respectively, 29/42 (69%) and 23/43 (53%) of the ova developed to morulae or blastocysts, while 1/42 (2%) developed to the morula stage in the absence of oviducal cells. Physical separation of the ova using a microporous membrane inserted between the oviducal cells and the ova did not affect ovum development, with 26/42 (62%) and 22/42 (52%) of ova developing to morulae or blastocysts in the BOC-0 and BOC-3 treatments, respectively. A high proportion of the morulae and blastocysts in Exp. 1 (57/66, 86%) and Exp. 2 (67/100, 67%) were of quality grades 1 or 2, with mean nuclei counts of 85 for morulae and 111 for blastocysts.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals

Role delineation for dietetic practitioners: empirical results.

In order to meet its need for a current, integrated picture of the dynamic profession of dietetics, The American Dietetic Association, with assistance from American College Testing, undertook a study focusing on the roles of entry-level dietetic technicians and registered dietitians and beyond-entry-level registered dietitians. A nationwide mail survey was conducted on random samples of 3,559 dietitians who had been registered for up to 3 years, 6,647 dietitians who had been registered for more than 3 years, and all 1,226 graduates (in the previous 3 years) from the 70 ADA-approved programs preparing dietetic technicians that agreed to participate (out of the 77 ADA-approved programs). Response rates of 77.5%, 78.7%, and 68.5% were achieved for the two samples of registered dietitians and the sample of dietetic technicians, respectively. The results show that the most commonly chosen work setting for the three respondent groups was "inpatient-care, acute-care facility." There were substantial differences among the three groups in the types of activities performed and in the level of responsibility for various kinds of activities. The beyond-entry-level registered dietitians were involved in the broadest range of activities and had the most responsibility for policy setting and other administrative activities, such as preparing budgets. The results of the study provide a detailed description of dietetic practice over a broad range of practitioner-experience levels, practice settings, and client groups.

Administrative Personnel

Effects of the putative phospholipid precursors, inositol, choline, serine and ethanolamine, on formation and expansion of rabbit blastocysts in vitro.

Rabbit morulae were cultured to blastocysts in various concentrations of the potential phospholipid precursors, myo-inositol, choline, serine and ethanolamine. Serine (20-2500 microM) had a significant stimulatory effect on blastocyst formation and blastocyst expansion and inositol (3-375 microM) had a significant stimulatory effect on blastocyst expansion. There was no significant stimulatory effect of choline or ethanolamine.

Animals

The effects of water-soluble vitamins on the expansion of rabbit blastocysts in vitro.

The vitamin requirements for culture of rabbit morulae to expanded blastocysts were examined. Early morulae were cultured for 5 days either in a control complete medium containing all the 11 water-soluble vitamins of F10 culture medium (biotin, pantothenate, choline, inositol, niacinamide, pyridoxine, riboflavin, thiamine, folic acid, B12, and lipoic acid) or in media with each vitamin omitted individually. Blastocyst diameters were measured at the end of culture. The omission of inositol, pyridoxine, riboflavin, and niacinamide resulted in large statistically significant decreases in blastocyst expansion. The omission of B12 resulted in a significant increase in blastocyst expansion indicating that the level present in F10 is toxic to rabbit blastocysts.

Animals

The effects of inhibitors of energy metabolism on the growth of one-cell rabbit ova to blastocysts in vitro.

Fertilized 1-cell rabbit ova were cultured in the presence of three oxidative phosphorylation inhibitors (cyanide, 2,4-dinitrophenol and oligomycin), two tricarboxylic acid (TCA) cycle inhibitors (malonate and fluoroacetate) and one glycolytic inhibitor (2-deoxyglucose). All three oxidative phosphorylation inhibitors killed ova at the 1-cell stage and the damage caused by each was similar. Malonate was non-toxic at all concentrations whereas some concentrations of fluoroacetate stopped growth at the 1-cell stage. This toxic effect could, in some circumstances, be reversed by the presence of acetate but not of glucose. 2-Deoxyglucose blocked only the transition from morula to blastocyst, and this was prevented by the addition of glucose to the medium; pyruvate, ribose, glycerol, and L-alpha-glycerol phosphate were ineffective. An active oxidative phosphorylation system and tricarboxylic cycle appear to be present and essential in the rabbit embryo from the 1-cell stage, but glycolysis may not be essential until blastocyst formation.

Animals

In vitro fertilization, culture, and transfer of rabbit ova.

Ovulated rabbit oocytes were fertilized in vitro in chemically defined media supplemented with bovine serum albumin and either cultured up to the expanding blastocyst stage or transferred to recipients after varying periods of culture. Embryos transferred after up to 72 hours of in vitro culture were born as viable young. Oocytes from young virgin does were superior to oocytes from nonvirgin does for the purpose of in vitro fertilization (54% versus 26% fertilized, P less than 0.01). Capacitated sperm from artificially inseminated capacitators resulted in fertilization rates slightly lower than those from naturally mated does (46% versus 57% fertilized, P less than 0.025). Removal of cumulus and corona cells from oocytes with hyaluronidase and repeated aspiration through a fine pipette resulted in lowered fertilization rates (51% versus 73%, P less than 0.025). Linbro Disposo Tray wells were as good as glass tissue-culture dishes for the in vitro mixing of gametes and were more convenient to use. Modified Ham's F10 medium was used to culture the in vitro-fertilized embryos. However, when a modified Brackett's medium was used instead of modified Ham's F10 for the initial 4-hour period after mixing gametes, more oocytes were fertilized (52% versus 28%, P less than 0.01).

Animals