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1.
Front Genet ; 12: 699920, 2021.
Article in English | MEDLINE | ID: mdl-34777457

ABSTRACT

Heat stress affects oocyte developmental competence and is a major cause of reduced fertility in heat stressed cattle. Negative effects of heat stress on the oocyte have been observed at morphological, biochemical and developmental levels. However, the mechanisms by which heat stress affects the oocyte at the transcriptional and epigenetic levels remain to be further elucidated. Here we aimed to investigate the effect of heat stress on oocyte quality, transcriptomic profiles and DNA methylation of oocytes collected through the transition from spring to summer under Louisiana conditions. Summer season resulted in a lower number of high quality oocytes obtained compared to the spring season. There was no difference in in vitro maturation rates of oocytes collected during spring as compared to summer. RNA sequencing analysis showed that a total of 211 and 92 genes were differentially expressed as a result of heat stress in GV and MII oocytes, respectively. Five common genes (E2F8, GATAD2B, BHLHE41, FBXO44, and RAB39B) were significantly affected by heat in both GV and MII oocytes. A number of pathways were also influenced by heat stress including glucocorticoid biosynthesis, apoptosis signaling, and HIPPO signaling in GV oocytes, and Oct4 pluripotency, Wnt/beta-catenin signaling, and melatonin degradation I in MII oocytes. In addition, fluorescent immunocytochemistry analysis showed no difference in global levels of DNA methylation and DNA hydroxymethylation at either the GV or MII stage between spring and summer oocytes. The results of this study contribute to a better understanding of the effect of heat stress on the molecular mechanisms altered in bovine oocytes.

2.
Reprod Fertil Dev ; 33(5): 338-348, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33602389

ABSTRACT

Embryo vitrification involves exposure to high concentrations of cryoprotectants and osmotic stress during cooling and warming in the cryopreservation process. Many of these factors can potentially affect gene expression. In this study, invitro-produced bovine embryos at the blastocyst stage were subjected to vitrification. Four recipients each were used for transferring non-vitrified (n=80) and vitrified (n=80) embryos. A total of 12 non-vitrified and 9 vitrified viable day-14 (D14) embryos were recovered by uterine flushing. RNA-seq analysis of the whole embryo or isolated trophectoderm (TE) from vitrified and fresh recovered D14 embryos revealed a total of 927 and 4376 genes with changed expression in embryos and TE isolates, respectively, as a result of vitrification. In addition, we found 671 and 61 genes commonly up- or downregulated in both vitrified whole embryos and TE. Commonly upregulated pathways by vitrification included epithelial adherens junctions, sirtuin signalling, germ cell-sertoli cell junction, ATM signalling, NER and protein ubiquitination pathways. The commonly downregulated pathways included EIF2 signalling, oxidative phosphorylation, mitochondrial dysfunction, regulation of eIF4 and p70S6K signalling and mTOR signalling pathways. Our analysis identified specific pathways and implicated specific gene expression patterns affecting embryo developmental competence that are important to cryopreservation.


Subject(s)
Blastocyst/metabolism , Cattle/embryology , Cryopreservation/veterinary , Gene Expression , Animals , Embryo Transfer/veterinary , Embryo, Mammalian/chemistry , Embryo, Mammalian/metabolism , Embryonic Development/physiology , Female , Fertilization in Vitro/veterinary , Gene Expression Regulation, Developmental , Sequence Analysis, RNA , Signal Transduction/genetics
3.
Physiol Rep ; 6(11): e13730, 2018 06.
Article in English | MEDLINE | ID: mdl-29870160

ABSTRACT

Physical inactivity is a leading cause of hypokinetic diseases - obesity, heart disease, diabetes, and certain types of cancers. Increased city walkability, better access to fitness facilities, and remediation of socioeconomic barriers prove successful for limited populations within the confines of stringently controlled environments; however, these strategies fail to reverse the ever-increasing physical inactivity epidemic on a global scale indicating the existence of other unidentified factors. These purported biological factors remain critical targets to understand the regulation of this complex phenotype. An estrogenic mechanism that incompletely or slowly adjusts physical activity levels following reintroduction of estrogenic compounds to surgically gonadectomized mice has been postulated to exist. Currently, this mechanism remains scrutinized due to concerns that elevated estrogen levels induce urinary bladder distension. The distension of the urinary bladder may mechanically disrupt physical activity, masking any physiological effects estrogen has on physical activity. The purpose of this study was to evaluate the effects of estrogen on physical activity levels while employing dose-related strategies to alleviate distension in mice. Wheel running data were collected under normal physiological conditions, following removal of endogenous sex steroids via orchidectomy, and during estrogen replacement at various doses (0%, 10%, 50% or 100% estrogen-containing implants) to induce varying degrees of urinary bladder distension. Wheel running distance (P = 0.005) and duration (P = 0.006) decreased after orchidectomy, but slowly increased following estrogen replacement. During the study, wheel running did not return to the levels observed in physiologically intact mice. Significant distension was not observed between estrogen treatment groups indicating that a slow-responding estrogen effect exists in male mice that prevents wheel running from returning to normal levels immediately following steroid reintroduction. The limited increase in wheel running during estrogen treatment following orchidectomy is not an artifact of induced urinary bladder distension.


Subject(s)
Estradiol/administration & dosage , Motor Activity/drug effects , Physical Conditioning, Animal , Urinary Bladder/drug effects , Animals , Dose-Response Relationship, Drug , Male , Mice, Inbred C57BL , Orchiectomy , Urinary Bladder/physiology
4.
Med Sci Sports Exerc ; 50(8): 1588-1595, 2018 08.
Article in English | MEDLINE | ID: mdl-29538178

ABSTRACT

The biological mechanisms regulating physical activity patterns appear to be linked to the sex hormones. Elucidation of these regulatory mechanisms may enhance individual physical activity patterns producing positive gains in health. PURPOSE: The purpose of this study was to evaluate the prolonged effects of estrogen on wheel running distance, duration, and speed in orchidectomized mice. METHODS: The physical activity patterns of 9-wk-old C57BL/6j male mice (n = 28) were observed. Wheel running distance, duration, and speed were assessed under physiological conditions for 7 d. Next, physical activity patterns were evaluated after bilateral orchidectomy (n = 14) or sham orchidectomy (n = 14) for an additional 7 d. Orchidectomized mice were provided estrogen containing capsules for three additional weeks; control mice were provided estrogen-free capsules. Wheel running distance, duration, and speed were analyzed by three two-way (treatment group-phase of study) analysis of variance tests. RESULTS: Wheel running speed was unaffected by sex hormone status. Distance (mean ± SD = 6.74 ± 2.13 km at baseline) decreased significantly after orchidectomy (2.27 ± 1.55 km) and remained low after initial estrogen treatment (3.04 ± 1.05 km). Prolonged estrogen exposure sustained a significant elevation of daily distance (4.47 ± 1.87 km). Prolonged estrogen exposure recovered and significantly sustained wheel running duration (baseline, 248 ± 60 min; postorchidectomy, 102 ± 53 min; prolonged exposure, 170 ± 63 min). CONCLUSIONS: Wheel running behavior was reduced significantly after orchidectomy and remained low after initial treatment with estrogens, but recovered to near control levels after 2 wk of exposure to estrogens. The estrogenic mechanism regulating wheel running behavior in male mice appears to induce an extensive but slow acting biological mechanism. Understanding the biological drive behind this mechanism may aid in developing useful therapeutic strategies to combat health issues related to physical inactivity.


Subject(s)
Estradiol/blood , Estradiol/physiology , Physical Conditioning, Animal , Physical Endurance/physiology , Animals , Body Mass Index , Mice , Mice, Inbred C57BL , Orchiectomy , Running/physiology
5.
J Equine Vet Sci ; 64: 69-76, 2018 May.
Article in English | MEDLINE | ID: mdl-30973156

ABSTRACT

This experiment assessed the hormonal production, secretory aspects, and changes in luteinizing hormone (LH) receptor gene expression of early induced ovulatory-sized follicles relative to the first ovulatory-sized follicles occurring naturally in the spring. Anovulatory mares were treated on January 21 with (1) 50 mg of estradiol cypionate (ECP, n = 8) alone or (2) with ECP followed by two 3-g sulpiride injections (n = 8), 5 and 12 days later. Half of each group also received complete follicle ablation via transvaginal aspiration before ECP treatment. Ovaries were scanned regularly until detection of a 32-35 mm follicle; follicular fluid was recovered via aspiration for analysis of hormonal concentrations. Blood was collected regularly to characterize plasma prolactin, LH, follicle stimulating hormone, progesterone, and estradiol concentrations. Mean date to first 35-mm follicle was earlier (P < .05) in sulpiride-treated mares: five of eight (63%) responded within 28 days of the first sulpiride injection. Ablation did not affect ovarian response. Plasma prolactin was stimulated (P < .0001) in ECP-sulpiride-treated mares for 16 days but did not dictate ovarian response. Estradiol stimulated plasma LH (P < .05), which was higher (P < .05) in treated mares that responded. There was no effect of treatment or ablation on follicular fluid concentrations of estradiol, progesterone, leptin, or insulin-like growth factor 1 or on LH receptor gene expression. These latter similarities indicate that ECP-sulpiride early induced follicles have apparently reached a degree of maturity equivalent to naturally occurring ovulatory-sized follicles later in the spring.

6.
Int J Oncol ; 52(1): 252-260, 2018 Jan.
Article in English | MEDLINE | ID: mdl-29115578

ABSTRACT

Early diagnosis of prostate cancer (PCa) is critical for the application of efficient treatment to PCa patients. However, the majority of PCas remains indolent from several months to several years before malignancy. Current diagnosis methods have limitations in their reliability and are inefficient in time cost. Thus, an efficient in vivo PCa cell xenograft model is highly desired for diagnostic studies in PCas. In the present study we present a standardized procedure to create a PCa cell xenograft model using zebrafish (Danio rerio) as the host. PC3-CTR cells, a cell line from adenocarcinoma with stable expression of calcitonin receptor (CRT), were subcutaneously injected into zebrafish larvae at 48 h post fertilization. The nursing conditions for the larvae were optimized with stable survival rates of post hatch and post PC3-CTR cell injection. In this system, the progression of PC3-CTR cells in vivo was evaluated by migration and proliferation of the cells. Massive migrations of PC3 cells in vivo were observed at post injection day (PID)3. The injected PC3-CTR cells eventually invaded the whole larval zebrafish at PID5. Quantification of PC3-CTR cell proliferation was done using quantitative PCR (qPCR) analysis targeting the expression profiles of two PCa housekeeping genes, TATA-binding protein (TBP) and hypoxanthine phosphoribosyltransferase 1 (HPRT1) encoding genes. The excessive proliferation of PC3 cells in vivo was detected with both qPCR assays. Expression levels of one non­coding gene, prostate cancer associated 3 gene (pca3), and two other genes encoding transient receptor potential ion channel Melastatin 8 (trpm8) and prostate-specific membrane antigen (psma), showed a significantly enhanced aggressiveness of PC3-CTR cells in vivo. The model established in the present study provides an improved in vivo model for the diagnosis of PCas efficiently. This PCa cell xenograft model can also serve as a tool for high throughput anti-PCa drug screening in therapeutic treatments.


Subject(s)
Disease Models, Animal , Prostatic Neoplasms/pathology , Zebrafish/embryology , Animals , Cell Line, Tumor , Cell Proliferation/physiology , Disease Progression , Heterografts , Humans , Male
7.
Physiol Behav ; 155: 149-56, 2016 Mar 01.
Article in English | MEDLINE | ID: mdl-26687894

ABSTRACT

PURPOSE: Increased physical activity is well known to improve health and wellness by modifying the risks for many chronic diseases. Rodent wheel running behavior is a beneficial surrogate model to evaluate the biology of daily physical activity in humans. Upon initial exposure to a running wheel, individual mice differentially respond to the experience, which confounds the normal activity patterns exhibited in this otherwise repeatable phenotype. To promote phenotypic stability, a minimum seven-day (or greater) acclimation period is utilized. Although phenotypic stabilization is achieved during this 7-day period, data to support acclimation periods of this length are not currently available in the literature. The purpose of this project is to evaluate the wheel running response in C57BL/6j mice immediately following exposure to a running wheel. METHODS: Twenty-eight male and thirty female C57BL/6j mice (Jackson Laboratory, Bar Harbor, ME) were acquired at eight weeks of age and were housed individually with free access to running wheels. Wheel running distance (km), duration (min), and speed (m∙min(-1)) were measured daily for fourteen days following initial housing. One-way ANOVAs were used to evaluate day-to-day differences in each wheel running character. Limits of agreement and mean difference statistics were calculated between days 1-13 (acclimating) and day 14 (acclimated) to assess day-to-day agreement between each parameter. RESULTS: Wheel running distance (males: F=5.653, p=2.14 × 10(-9); females: F=8.217, p=1.20 × 10(-14)), duration (males: F=2.613, p=0.001; females: F=4.529, p=3.28 × 10(-7)), and speed (males: F=7.803, p=1.22 × 10(-13); females: F=13.140, p=2.00 × 10(-16)) exhibited day-to-day differences. Tukey's HSD post-hoc testing indicated differences between early (males: days 1-3; females: days 1-6) and later (males: days >3; females: days >6) wheel running periods in distance and speed. Duration only exhibited an anomalous difference between wheel running on day 13 and wheel running on days 1 through 4 in males. In females, duration exhibited anomalous differences due to abnormally depressed wheel running on day 6 and abnormally elevated wheel running on day 14. Limits of agreement and mean difference statistics indicated stable phenotypic variability with an up-trending daily mean for distance and speed that stabilized within the first three days in males and within eight days in females. Duration exhibited stable variability after nine days in males and after seven days in females. CONCLUSION: Although it is common practice to allow a prolonged (≥ seven day) acclimation period prior to recording wheel running data, the current study suggests that phenotypic stabilization of all three indices is achieved at different times with distance and speed exhibiting stability by day three in males and day eight in females. Duration exhibits stability by day nine in males and day seven in females.


Subject(s)
Motor Activity , Running , Animals , Female , Male , Mice, Inbred C57BL , Phenotype , Sex Characteristics , Time
8.
Health Technol (Berl) ; 6(2): 89-99, 2016 Jul.
Article in English | MEDLINE | ID: mdl-35757564

ABSTRACT

Although health information technology (HIT) is essential in improving health outcomes and health care quality in the United States, current research lacks information regarding persuasive features (technology features designed to promote behavioral change) in HIT interventions for managing chronic diseases among older adults (aged 50 and older). To provide an overview of the persuasive features within current HIT interventions for managing chronic diseases among older adults, we conducted a systematic review to examine the use and efficacy of web-based chronic disease self-management for older adults. Persuasive system features included in HIT interventions were examined. Interventions presented in the final 24 studies were designed to improve health outcomes such as self-efficacy, self-care, and physical activity among participants with a chronic health condition. Examples of health conditions include diabetes, COPD, and arthritis. Among the 24 studies, several persuasive features were commonly used to support positive outcomes; 12 reported success in all measured outcomes and 10 reported a mix of both positive and unsuccessful outcomes pertaining to improvements in healthier lifestyles, self-management, chronic disease knowledge, blood pressure, and daily functioning. Only two of the studies included in our systematic review found no improvement in health outcomes and experienced high attrition rates after implementation of the persuasive systems intervention. It is important to identify specific persuasive features within interventions. Further research is needed in specifying persuasive features within technology-based interventions to help healthcare professionals modify interventions to improve chronic disease outcomes for older populations.

9.
BMC Vet Res ; 9: 194, 2013 Oct 05.
Article in English | MEDLINE | ID: mdl-24093969

ABSTRACT

BACKGROUND: Surgical site infections (SSIs) are a recognized risk of any surgical procedure in veterinary medicine. One of the keys to prevention of SSIs is reducing exposure of the surgical site to endogenous and exogenous microbes, beginning in the preoperative period. While guidelines are available for preoperative preparation procedures, there has been no objective investigation of compliance with these recommendations in veterinary practices. The objectives of this pilot study were to describe preoperative patient and surgeon preparation practices in a sample of non-equine companion animal veterinary clinics, and to determine if there were any areas that consistently did not meet current guidelines. RESULTS: Observation of preparation practices was performed in 10 clinics over 9-14 days each using up to 3 small wireless surveillance cameras. Data were coded for 148 surgical patients, and 31 surgeons performing 190 preoperative preparations. When patient hair removal was observed, it was most commonly done using clippers (117/133, 88%), and in only one case was it performed prior to anesthetic induction. Patient contact time with soap ranged from 10-462 s (average of clinic means 75 s, average of clinic medians 67 s), and with alcohol from 3-220 s (average of clinic means 44 s, average of clinic medians 37 s). Alcohol-based hand rub (AHR) was used preoperatively in 2/10 facilities, but soap-and-water hand scrub was most commonly used at all clinics. Proximal-to-distal scrubbing was noted in 95/142 (67%) of soap-and-water scrubs. Contact time during surgeon hand preparation ranged from 7-529 s (average mean 121 s, average median 122 s) for soap-and-water and from 4-123 s (average mean 25 s, average median 19 s) for AHR. No significant changes in practices were identified over time during the observation period. Practices that did not conform to guidelines available in major companion animal surgical textbooks were commonly observed. CONCLUSIONS: Some preoperative preparation practices were relatively consistent between clinics in this study, while others were quite variable. Contact times with preoperative preparatory solutions for both patients and surgeons were often shorter than recommended. Evidence-based guidelines for these procedures in veterinary medicine should be established and implemented in order to help reduce preventable SSIs, while maintaining efficiency and cost-effectiveness.


Subject(s)
Clinical Competence , Guideline Adherence , Pets , Preoperative Period , Surgery, Veterinary/standards , Veterinarians , Animals , Hand Disinfection , Ontario
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