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Biomedical subjects

R W Wright

Publications and source records attributed to R W Wright.

At least 73 records · Page 4Linked to original sources
PubMed1983

In vitro fertilization of ovulated and ovarian ovine oocytes.

In vitro fertilization of ovine ovulated and ovarian oocytes was attempted after capacitation of ejaculated spermatozoa by a variety of methods. All sperm incubations and oocyte cultures were performed in a modified Krebs Ringer bicarbonate (KRB) medium. High ionic strength (HIS) medium was prepared by adding NaCl to provide an osmolarity of approximately 370 mOsmol/kg. All oocytes were obtained from progestogen-synchronized and follicle-stimulating hormone-treated ewes. Ovulated oocytes were recovered 64 h after progestogen withdrawal. Ovarian oocytes were recovered 45 h after progestogen withdrawal. Oocytes were incubated with spermatozoa in microdrops for 6 h, transferred to fresh medium and cultured for 48 h. In the first series of experiments, capacitation was attempted by either preincubation in KRB, washing spermatozoa with KRB medium or treatment of spermatozoa with HIS medium. Spermatozoa washed with KRB penetrated three of 61 (5%) oocytes and spermatozoa incubated in HIS medium penetrated eight of 209 (4%) oocytes. In the second series of experiments, spermatozoa were capacitated by incubation with ovine cumulus cells or in the uterus of a rabbit. A 33% fertilization rate was observed with spermatozoa recovered from the rabbit uterus and a 28% rate with spermatozoa incubated with cumulus cells. Treatment with HIS medium previously shown to capacitate bovine and rabbit spermatozoa failed to capacitate ram spermatozoa; however, fertilization was observed after capacitation by cumulus cells or in the rabbit uterus.

Animals↗
PubMed1983

Benefits of a community-hospital pulmonary rehabilitation program.

Pulmonary rehabilitation can be a beneficial and cost-effective mode of therapy for patients with chronic obstructive pulmonary disease (COPD). At St Joseph's Hospital in Stockton, California, we established a multi-disciplinary, 10-week program combining outpatient education with aerobic exercise to promote both improved subjective well-being and increased exercise tolerance in patients with COPD. We studied 74 patients who had completed the program at least 1 year before the study began. Subjective data about the program were collected by use of a questionnaire. Changes in physical work capacity were measured by use of stress tests performed before and after the program was completed. Of the 57 patients responding to the questionnaire, most felt that the program had improved the quality of their lives. After the program was completed, significant decreases were seen in oxygen consumption, minute ventilation, and heart rate during treadmill exercise. The number of days of hospitalization for the group decreased from 497 in the year before completing the program to 34 the year after.

California↗
PubMed1982

The ability of fetal calf serum, new-born calf serum and normal steer serum to promote the in vitro development of bovine morulae.

The objective of this study was to compare fetal calf serum, new-born calf serum and normal steer serum as medium supplements in the development of bovine morulae in vitro . Bovine morulae were cultured in Hams F-10 tissue culture medium (HF-10) supplemented with 5% or 10% (v/v) fetal calf serum (FCS), new-born calf serum (NBCS) or normal steer serum (NSS). Embryos were recovered at slaughter from mixed bred donor cows of mixed breeding following estrus synchronization with prostaglandin and superovulation with follicle stimulating hormone. A total of 88 morulae were recovered, washed in HF-10 + 1% Bovine Serum Albumin and randomly assigned to treatments. Embryos were cultured in microdrops of medium under paraffin oil at 37 degrees C in a 5% CO(2) humidified atmosphere. Observations for stage of development were made every 24 hours. In vitro development was analyzed by assigning to each embryo a value of 0-5 based on the most advanced stage reached (0= no development, 5= development to a hatched blastocyst). Analysis of variance of these data revealed a significant treatment effect (P<.001) while no level effect or treatment x level interaction was apparent. Comparison of treatment means by Duncans new mulitple range test showed that NSS was superior to NBCS (P<.05) which was in turn superior to FCS (P<.05) as supplements of HF-10 in promoting the in vitro development of bovine morulae.

Journal Article↗
PubMed1982

Induction of estrus and superovulation in seasonally anestrous ewes.

The induction of estrus in 17 previously cycling nulliparous ewes, 9 to 10 months of age, was attempted with Medroxyprogesterone acetate (MAP) pessaries during the early anestrous period (March-April). Ewes were verified to be anestrous by the lack of estrous behavior in the presence of a vasectomized ram and by a radioimmunoassay for serum progesterone in two samples taken 7 days apart showing less than 1 ng/ml serum progesterone. Superovulation was attempted with injections of either FSH or FSH + LH. MAP vaginal pessaries remained in place for a period of 12 days and FSH was administered to all ewes (IM) at 12 hr intervals over a 3 day period; 5 mg was injected twice on day 11 after pessary insertion, followed by 4 and 3 mg injections twice daily on each succeeding day, for a total of 24 mg per ewe. Nine ewes were given 25 mg LH (IV) within 8 hrs after the onset of behavioral estrus in addition to FSH. Ewes were hand-mated to several rams at 12 hr intervals throughout the estrus period. Ovulation and fertilization rates were recorded for each ewe following midline laparotomy and embryo collection. All ewes were in estrus between 36 and 48 hrs after removal of the MAP pessaries. In ewes injected with FSH only, 8 of 8 ovulated with a mean ovulation rate of 6.0 +/- 4.4 and a fertilization rate of 70%. Nine of 9 ewes receiving both FSH + LH ovulated with a mean ovulation rate of 13.9 +/- 13.1 and a fertilization rate of 72%. Statistical analysis by Students t-test resulted in differences in number of ova recovered (P<.05) between FSH only and FSH + LH treated ewes and a trend towards increased ovulation rate in FSH + LH treated ewes. These results show that early seasonally anestrous ewes can be successfully induced and synchronized for estrus with MAP pessaries and the number of ova recovered is increased with the inclusion of LH in the superovulation regime.

Journal Article↗
PubMed1982

Development of one-cell porcine embryos in two culture systems.

The effect of culture system and protein supplementation on the development of one-cell porcine embryos was investigated. One hundred and sixty-four one-cell embryos were collected at slaughter from 19 handmated gifts. Culture systems evaluated were microdrops of Whitten's medium (WM) under paraffin oil (M) or tubes with 4.0 ml of WM (T). Also tested was T with a 2.0 ml paraffin oil overlay (O). Media evaluated were WM with: no bovine serum albumin (-BSA), 15 mg/ml BSA (+BSA) or 10% (v/v) heat-treated porcine serum (+HTPS). Twenty-nine, 29, 28, 29, 28 and 21 one-cell embryos were assigned to treatments T + BSA + O, T - BSA, M + BSA, M - BSA and M + HTPS, respectively. All cultures were conducted at 37 C in a humidified atmosphere of 5% CO2 in air. At the cessation of division, embryos were fixed and stained, and each was assigned a cleavage index bases on the number of divisions completely in culture. The mean cleavate indexes for embryos cultured in T + BSA + O (2.07) and T + BSA (1.97) were not significantly different, but both were greater (P less than .05) than the indexes for T - BSA (1.09), M + BSA (1.12), M - BSA (.82) and M + HTPS (.86). Mean cleavage indexes for embryos cultured in T - BSA, M + BSA, M - BSA and M + HTPS were not significantly different. More (P less than .05) embryos developed to the blastocyst stage in T + BSA + O (6/29) than in either T - BSa (0.28) or M BSA (0.28). Fragmentation was greater (P less than .05) in embryos cultured in M - BSA than in embryos cultured in tubes. These results suggest that culture tubes of WM with 1.5% BSA are superior to microdrops and WM with 10% HTPS in supporting the in vitro development of one-cell porcine embryos.

Animals↗
PubMed1982

Observations on the development of bovine morulae on various cellular and noncellular substrata.

The objective was to determine the effect of various cell types on the development of bovine embryos in vitro. Morulae were collected from beef and dairy cows 4 to 5 d after the onset of estrus (d 0). Embryos were randomly allocated to nine treatments: (1) microdrops of Ham's F-10 medium (HF-10) under paraffin oil (HF-10); (2) HF-10 over a substratum of collagen without paraffin oil (HF-10/clg); (3) HF-10 with bovine uterine fibroblasts grown on a collagen substratum (HF-10/clg-fib); (4) Minimal Essential Medium (MEM) without paraffin oil (MEM); (5) microdrops of MEM under paraffin oil (MEM/oil); (6) MEM with bovine uterine fibroblasts (MEM/Buf; (7) MEM with bovine testicular fibroblasts (MEM/Btes); (8) MEM exposed to uterine fibroblasts for 24 h to condition the medium (MEM/Con), and (9) MEM with 1 mm cubes of bovine endometrial tissue (MEM/End). In all cases, media were supplemented with 10% (v/v) heat-treated fetal calf serum. Observations were made at 24 h intervals, with the stage of embryo development recorded. Morulae developed into expanded blastocysts more frequently (P less than .05) in HF-10, MEM, MEM/oil, MEM/Buf, MEM/Btes and MEM/Con than in HF-10/clg, HF-10/clg-fib and MEM/End. More (P less than .01) blastocysts hatched in MEM/Buf and MEM/Btes than in the other media. In addition, nine of 12 (MEM/Buf), eight of 11 (MEM/Btes) and two of two (HF-10/clg-fib) hatched blastocysts attached to the fibroblast monolayers, an observation that was uncommon in treatments without cells. These data suggest that the co-culture of bovine embryos with bovine fibroblasts in a superior system for promoting embryo hatching and attachment in vitro.

Animals↗
PubMed1982

Variation in porcine zona pellucida morphology following pronase treatment.

The effects of cell stage and day of embryo collection on the pronase-induced zona pellucida morphology in pig embryos were investigated. Three hundred and seventy-two two- to eight-cell embryos were treated for 3.0 min in 5.0% pronase in Whitten's Medium. Responses in zona pellucida morphology observed after pronase treatment were: (1) absent, (2) stretched and (3) intact. Each pig was coded as to the type of zona pellucida morphology its embryos possessed after enzyme treatment according to the following scale: (1)--only intact, (2)--intact and stretched, (3)--only stretched, (4)--stretched and absent and (5)--only absent. Also, the number of embryos of a particular cell stage was expressed as a fraction of the total number of embryos collected from each pig. The incidence of intact zonae pellucidae was greatest (P less than .05) among two- to three-cell embryos and the incidence of absent zonae pellucidae was greatest (P less than .05) among six-to eight-cell embryos. A significant correlation (r = .79) was observed between day of embryo collection and coded zona pellucida morphology. The results suggest that the pronase-induced zona pellucida morphology observed is dependent on cell stage and day of embryo collection.

Animals↗
PubMed1981

Protein content of porcine embryos during the first nine days of development.

Little is known about the physiochemical aspects of porcine embryos prior to implantation. The purpose of this study was to quantitate the total protein content of porcine embryos from fertilization through day 9 of development. Thirty-seven gilts and two sows were hand mated and the reproductive tracts collected at slaughter 1 to 9 days after the onset of estrus. The uteri were flushed with phosphate buffered saline (PBS), and embryos were collected, washed with PBS and transferred directly to test tubes containing distilled water. Only embryos which appeared morphologically normal were used. Protein content was determined by the Bio-Rad microassay. Standard curves were constructed for each assay using. 8 to 19 microg gamma globulin (Bio-Rad assay). Protein standards were run in triplicate. Regression lines were calculated for protein standards, and the resulting line was used to determine total protein in the unknown samples. Protein content of unfertilized eggs and embryos increased steadily through days 3, 4 and 5 of development, from 273 to 334, 491 and 620 ng, respectively. This result suggests that the protein content of porcine embryos increases only slightly from fertilization through day 5 of development. A dramatic increase in embryo protein content was observed between days 6 and 9 of development, which is the time of blastocyst formation and hatching of the embryo from the zona pellucida.

Journal Article↗
PubMed1981

FSH or FSH plus LH superovulation in ewes following estrus synchronization with medoxyprogesterone acetate pessaries.

The estrous cycles of 28 ewes 9 to 10 months of age were synchronized with Medoxyprogesterone (MAP) pessaries. Superovulation was attempted by injecting either (follicle stimulating hormone) FSH or FSH plus Luteinizing Hormone (LH). MAP pessaries were in place for 12 days. FSH was administered (IM) to all ewes at 12-hr intervals over a 3-day period, 5 mg injected twice on day 11 after pessary insertion, followed by 4 and 3 mg twice daily on days 12 and 13, respectively. LH (25 mg injected IV) was given to 14 ewes within 8 hr after the onset of behavioral estrus. All ewes were hand mated with several rams at 12-hr intervals from the onset to the end of behavioral estrus. Ovulation, embryo recovery and fertilization rates were recorded for each ewe. Of 14 ewes injected with only FSH, 13 ovulated, with a mean ovulation rate of 8.2 +/- 5.6; embryo recovery rate averaged 62%, and fertilization rate was 97%. All 14 ewes given both FSH + LH ovulated, with an ovulation rate of 8.9 +/- 5.8 per ewe; embryo recovery averaged 70%, and 91% of all embryos recovered were fertilized. No statistical differences in ovulation, embryo recovery or fertilization rates were found between the FSH and FSH + LH superovulation treatment groups. In addition, no difference in the number of ewes showing estrus or duration of behavioral estrus was noted between FSH and FSH + LH treatments.

Animals↗
PubMed1980

Lactate dehydrogenase isoenzyme patterns as a method of pregnancy detection in cattle.

The objective of this study was to evaluate serum lactate dehydrogenase isoenzyme patterns in open and pregnant Holstein and Hereford cows as a method of detecting pregnancy. Serum samples were collected from 26 Holstein and 13 Hereford cows and lactate dehydrogenase isoenzyme patterns were examined by electrophoresis and quantitated by scanning densitometry. Lactate dehydrogenase isoenzyme(4) and LDH(5) were found in higher concentration (P </= .05) in pregnant versus open Holstein cows. Twelve of 14 and 10 of 12 Holstein cows were correctly diagnosed as being pregnant and open, respectively by examining differences in serum concentrations of isoenzymes LDH(4) and LDH(5). Pregnancy was detected as early as 36 days of gestation. No differences were found in serum LDH isoenzyme patterns between pregnant and open Hereford cows. However, differences (P </= .05) in concentration of all five LDH isoenzymes were observed between Holstein and Hereford cows, which may lend insight into the metabolic significance of the elevation of LDH(4) and LDH(5) in pregnancy. The results suggest that elevation of serum LDH(4) and LDH(5) may be used as a means of pregnancy detection in the Holstein but not the Hereford cow.

Journal Article↗
PubMed1980

Influence of culture media on in vitro fertilization of ovine tubal oocytes.

The ability of Synthetic Oviductal Fluid (SOF) and Minimum Essential Medium (MEM) to support sperm binding, sperm penetration and subsequent cell division of ovine tubal oocytes in vitro was evaluated. These media contained no protein, 3% (w/w) bovine serum albumin (BSA) or 20% (v/v) lamb serum (LS). Midventral laparotomies were performed on 49 ewes synchronized with progesterone and then superovulated, and tubal oocytes were collected by flushing the oviducts. Oocytes were pooled and randomly added to 2 X 10(7) ejaculated spermatozoa in 1 ml of treatment media that had been preincubated in tubes for 3 hr at 37 C under 5% CO2 in air. After an additional 3 hr of culture in a rotating tissue culture drum, oocytes were further cultured in microdrops of the same medium for 48 hr and observed for sperm penetration, cell division and fragmentation. Oocytes were then stained with aceto-orcein and observed for penetration, multiple nuclei and bound sperm. Percentage of oocytes showing penetration in SOF, SOF+ BSA, SOF+LS, MEM, MEM+BSA and MEM+LS was 14, 3.6, 7.8, 11.1, 8.7 and 12.8, respectively; percentage of oocytes cleaving was 8, 3.6, 5.9, 4.4, 4.3 and 4.3; percentage of oocytes fragmenting was 40, 60, 60.8, 20, 60.9 and 29.8, and the average number of sperm cells bound per oocyte was 82, 177, 117, 41, 56 and 47. No cell division was observed for control oocytes (no sperm added), but 72.7, 80 and 76.9% fragmented in SOF, SOF+BSA and SOF+LS, respectively. No difference was found among the media in their ability to support sperm penetration and subsequent cell division in vitro. All media tested supported a high incidence of sperm binding and oocyte fragmentation.

Animals↗