Prefrontal cortex activity and gait in Parkinson's disease with cholinergic and dopaminergic therapy

Objectives: Degradation of striatal dopamine in Parkinson’s disease (PD) may initially be supplemented by increased cognitive control mediated by cholinergic mechanisms. Shift to cognitive control of walking can be quantified by prefrontal cortex (PFC) activation. Levodopa improves certain aspects of gait and worsens others, and cholinergic augmentation influence on gait and PFC activity remains unclear. This study examined dopaminergic and cholinergic influence on gait and PFC activity while walking in PD. Methods: A single-site, randomized, double-blind, cross-over trial examined effects of levodopa and donepezil in PD. 20 PD participants were randomized and 19 completed the trial. Participants were randomized to either levodopa+donepezil (5mg) or levodopa+placebo treatments, with two-weeks with treatment and a two-week washout. The primary outcome was change in PFC activity while walking, and secondary outcomes were change in gait, dual-task performance and attention. Results: Levodopa decreased PFC activity compared to Off medication (effect size: -0.51), whereas the addition of donepezil reversed this decrease. Gait speed and stride length, under single and dual-task conditions, improved with combined donepezil and levodopa compared to Off medication (effect size: 1 for gait speed and 0.75 for stride length). Dual-task reaction time was quicker with levodopa compared to Off medication (effect size: -0.87), and accuracy improved with combined donepezil and levodopa (effect size: 0.47). Conclusions: Cholinergic therapy, specifically donepezil 5mg/day for two-weeks, can alter PFC activity when walking, and improve secondary cognitive task accuracy and gait in PD. Further studies will investigate whether higher PFC activity while walking is associated with gait changes

In vitro embryo production using ovaries removed from culled cows

The objective was to utilize in vitro maturation and fertilization to maximize embryo production from culled dairy cows. Ovaries were removed (via a colopotomy technique) from culled Holstein cows (n = 21) 2 d after standing estrus (T1), 2 d after treatment with 40 mg follicle stimulating hormone (FSH) given at standing estrus (T2), or at an unknown stage of the estrous cycle (T3).Treatment with FSH increased (P &lt; 0.05) oocyte recovery rate (mean ± SEM, 14.6 ± 2.2, 25.4 ± 3.4, and 11.1 ± 2.6 oocytes ovary–1), for groups T1, T2 and T3, respectively, and the number of blastocysts obtained (1.6 ± 0.5, 4.4 ± 0.4 and 1.6 ± 0.6 blastocysts ovary–1). Culled dairy cows of high genetic merit are potential embryo donors, with an average of six to eight transferable embryos obtained from each FSH-treated cow. Key words: FSH treatment, oocyte recovery, IVM, IVF, culled cows </jats:p

Pregnancy rates and peripheral progesterone levels following Ovsynch or CIDR ovulation synchronization/timed artificial insemination protocols in postpartum dairy cows

Peripheral progesterone (P4) concentrations as well as pregnancy rates (PR) between cows treated with Ovsynch or CIDR ovulation synchronization/TAI protocols were compared. Two hundred and twenty-seven postpartum lactating Holstein cows were randomly assigned to Ovsynch (n = 111) or CIDR (n = 116) ovulation synchronization/TAI protocols. Pregnancy was diagnosed by ultrasonography at day 35 after TAI and later confirmed by rectal palpation at day 60 post TAI. Milk samples were taken from the beginning of treatment (day -10) until day 35 after TAI (day 0) for P4 determination. Pregnancy rates for Ovsynch and CIDR groups of cows were 31 and 41%, respectively. The PR of ovulation synchronized cows for Ovsynch and CIDR groups were 49 and 69%, respectively. Progesterone levels during the sampling period were similar (P &gt; 0.05) between Ovsynch and CIDR treated cows. Key words: Pregnancy rate, progesterone, Ovsynch, CIDR, cows </jats:p

GnRH receptor messenger ribonucleic acid expression in bovine ovary

The present study was undertaken to investigate the mRNA expression for gonadotropin-releasing hormone (GnRH) receptor in bovine ovary. Granulosa cells from small (&lt; 4 mM), medium (5–8 mM) and large follicles (&gt; 8 mM) and tissues from corpora lutea (CL) of different stages: Stage I (days 1–4), Stage II (days 5–10), Stage III (days 11–17), and Stage IV (days 18–21, days after ovulation) were harvested from bovine ovaries collected at a local abattoir. The mRNA isolated from representative samples was subjected to reverse transcription-polymerase chain reaction (RT-PCR) using gene sequence specific primers. The resultant PCR amplified gonadotropin-releasing horm one receptor (GnRH-R) cDNA products were identified and confirmed through Southern blot hybridization and nucleotide sequence analysis, respectively. The results showed the presence of GnRH-R mRNA transcripts in both follicles and CL. Key words: Bovine, granulosa cells, corpus luteum, GnRH receptor, mRNA </jats:p

Development of in vitro tests to predict fertility of bulls

The overall objective was to develop an in vitro test to predict fertility of bulls in the field. We investigated the bull effect on in vitro embryo production, zona binding and acrosome reaction, and the correlation of this effect to field fertility meas ured by 60–90 d non-return rate. Frozen semen from three separate ejaculates of eight unrelated young bulls, obtained from an artificial insemination (AI) center, was used. On thawing, ejaculates from each bull were pooled, motile sperm were selected and (a) subjected to immunofluorescent assay at 0 and 4 h of incubation in capacitation medium to assess acrosome status, (b) used in an in vitro fertilization assay system to assess cleavage and blastocyst production rates, and (c) sperm-zona binding assay was carried out to determine the number of sperm bound to the zona pellucida of mature oocytes. Percentage of pre-freeze motile sperm (PrFM) and non-return rate data were obtained from the AI center. PrFM, percentage of acrosome reacted sperm at 0 h (AR1), increase in percentage of acrosome reacted sperm after 4 h (InAR) and sperm-zona binding rates (ZB) differed (P &lt; 0.05) among sperm samples obtained from different young bulls. Significant correlations (P &lt; 0.05) were observed between PrFM and AR1 (r = -0.31), InAR (r = 0.36), and ZB (r = 0.32). AR1 was negatively correlated to ZB (r = -0.27) and cleavage rate (r = -0.20), InAR was positively correlated with ZB (r = 0.31) and cleavage rate (r = 0.26). None of the in vitro tests was correlated with non-return rate. These findings indicate that along with pre-freeze motility, a combination of in vitro tests including the percentage of spontaneously acrosome reacted sperm at thawing, might be useful in predicting bull field fertility. Such a combination of assays, however, has yet to be determined. Key words: Field fertility, acrosome reaction, zona binding, IVF, fertility assay </jats:p