https://ogma.newcastle.edu.au/vital/access/ /manager/Index ${session.getAttribute("locale")} 5 https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:39561 Wed 27 Jul 2022 14:35:53 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:53339 Wed 22 Nov 2023 10:19:55 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:34145 Wed 13 Feb 2019 11:43:06 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:29909 P < 0.001) were found between ALDH expression and various motility parameters of stallion spermatozoa including the percentage of progressive (r = 0.79) and rapidly motile (r = 0.79) spermatozoa, whereas repeated measurements over 24 h revealed highly significant correlations among progressive motility loss, 4HNE accumulation, and ALDH expression (P ≤ 0.001). ALDH inhibition resulted in a spontaneous increase in 4HNE levels in viable cells (21.1 ± 5.8% vs. 42.6 ± 5.2%; P ≤ 0.05) and a corresponding decrease in total motility (41.7 ± 6.2% vs. 6.4 ± 2.6%; P ≤ 0.001) and progressive motility (17.0 ± 4.1% vs. 0.7 ± 0.4%; P ≤ 0.001) of stallion spermatozoa over 24 h. Similarly, inhibition of ALDH in 4HNE-challenged spermatozoa significantly reduced total motility over 4 h (35.4 ± 9.7% vs. 15.3 ± 5.1%, respectively; P ≤ 0.05). This study contributes valuable information about the role of the ALDH enzymes in the maintenance of stallion sperm functionality, with potential diagnostic and in vitro applications for assisted reproductive technologies.]]> Wed 11 Apr 2018 16:45:10 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:24546 In vitro sperm storage is a necessary part of many artificial insemination or in vitro fertilization regimes for many species, including the human and the horse. In many situations spermatozoa are chilled to temperatures between 4 and 10°C for the purpose of restricting the metabolic rate during storage, in turn, reducing the depletion of ATP and the production of detrimental by-products such as reactive oxygen species (ROS). Another result of lowering the temperature is that spermatozoa may be "cold shocked" due to lipid membrane phase separation, resulting in reduced fertility. To overcome this, a method of sperm storage must be developed that will preclude the need to chill spermatozoa. If a thermally induced restriction-of-metabolic-rate strategy is not employed, ATP production must be supported while ameliorating the deleterious effects of ROS. To achieve this end, an understanding of the nature of energy production by the spermatozoa of the species of interest is essential. Human spermatozoa depend predominantly on glycolytic ATP production, producing significantly less ROS than oxidative phosphorylation, with the more efficient pathway predominantly employed by stallion spermatozoa. This review provides an overview of the implications of sperm metabolism for in vitro sperm storage, with a focus on ambient temperature storage in the stallion.]]> Wed 11 Apr 2018 14:27:26 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:15069 Wed 11 Apr 2018 13:57:41 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:21426 Wed 11 Apr 2018 11:46:49 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:27621 Wed 11 Apr 2018 10:16:30 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:26316 Wed 11 Apr 2018 09:24:47 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:52821 Wed 07 Feb 2024 14:59:02 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:50158 Wed 05 Jul 2023 15:35:31 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:54788 Tue 12 Mar 2024 14:34:36 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:50661 Tue 01 Aug 2023 13:06:32 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:38313 Thu 26 Aug 2021 13:31:44 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:42127 P < 0.001). Furthermore, the deleterious effects of GSH depletion using menadione and 1,3 dimethoxy 1,4, naphtoquinone (DMNQ) were able to be prevented by the addition of cysteine, but no other antioxidant. Pre-incubation with cysteine prevented menadione and DMNQ induced damage to sperm membranes after 1 h (P < 0.001; P < 0.05) and after 3 h of incubation (P < 0.001, P < 0.05). Pre-incubation with cysteine ameliorated both the menadione- and DMNQ-induced increase in 4-hydroxynonenal (P < 0.001). As cysteine is a precursor of GSH, we hypothesized that stallion spermatozoa are able to synthesize this tripeptide using exogenous cysteine. To test this hypothesis, we investigated the presence of two enzymes required to synthesize GSH (GSH and GCLC) and using western blotting and immunocytochemistry we detected both enzymes in stallion spermatozoa. The inhibition of GCLC reduced the recovery of GSH by addition of cysteine after depletion, suggesting that stallion spermatozoa may use exogenous cysteine to regulate GSH. Other findings supporting this hypothesis were changes in sperm functionality after BSO treatment and changes in GSH and GSSG validated using HPLC-MS, showing that BSO prevented the increase in GSH in the presence of cysteine, although important stallion to stallion variability occurred and suggested differences in expression of glutamate cysteine ligase. Mean concentration of GSH in stallion spermatozoa was 8.2 ± 2.1 μM/10⁹ spermatozoa, well above the nanomolar ranges per billion spermatozoa reported for other mammals.]]> Thu 25 Aug 2022 12:01:39 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:54274 Thu 15 Feb 2024 14:39:30 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:30931 41 completed weeks of gestation (late-term) would show changes consistent with aging that would also be present in placentas associated with stillbirths. Objective: We sought to determine whether placentas from late-term pregnancies and unexplained stillbirth show oxidative damage and other biochemical signs of aging. We also aimed to develop an in vitro term placental explant culture model to test the aging pathways. Study Design: We collected placentas from women at 37-39 weeks’ gestation (early-term and term), late-term, and with unexplained stillbirth. We used immunohistochemistry to compare the 3 groups for: DNA/RNA oxidation (8-hydroxy-deoxyguanosine), lysosomal distribution (lysosome-associated membrane protein 2), lipid oxidation (4-hydroxynonenal), and autophagosome size (microtubule-associated proteins 1A/1B light chain 3B, LC3B). The expression of aldehyde oxidase 1 was measured by real-time polymerase chain reaction. Using a placental explant culture model, we tested the hypothesis that aldehyde oxidase 1 mediates oxidative damage to lipids in the placenta. Results: Placentas from late-term pregnancies show increased aldehyde oxidase 1 expression, oxidation of DNA/RNA and lipid, perinuclear location of lysosomes, and larger autophagosomes compared to placentas from women delivered at 37-39 weeks. Stillbirth-associated placentas showed similar changes in oxidation of DNA/RNA and lipid, lysosomal location, and autophagosome size to placentas from late-term. Placental explants from term deliveries cultured in serum-free medium also showed evidence of oxidation of lipid, perinuclear lysosomes, and larger autophagosomes, changes that were blocked by the G-protein-coupled estrogen receptor 1 agonist G1, while the oxidation of lipid was blocked by the aldehyde oxidase 1 inhibitor raloxifene. Conclusion: Our data are consistent with a role for aldehyde oxidase 1 and G-protein-coupled estrogen receptor 1 in mediating aging of the placenta that may contribute to stillbirth. The placenta is a tractable model of aging in human tissue.]]> Thu 09 Dec 2021 11:03:44 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:10153 Sat 24 Mar 2018 08:07:27 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:19260 Sat 24 Mar 2018 08:06:38 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:17664 Sat 24 Mar 2018 07:57:48 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:17995 Sat 24 Mar 2018 07:56:35 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:20027 Sat 24 Mar 2018 07:50:55 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:29650 Sat 24 Mar 2018 07:41:51 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:26608 30%). Couples with otherwise unexplained recurrent miscarriage had significantly higher DFI than those with other causes identified on routine screening (P = 0.012). Conclusions: In couples experiencing RM, 30% (32/108) of men had sperm with high levels of DNA fragmentation (DFI > 15%). This may be a contributing factor to the clinical syndrome of RM, and future clinical trials of therapies for these couples are warranted.]]> Sat 24 Mar 2018 07:33:59 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:24127 Sat 24 Mar 2018 07:16:32 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:48243 Sat 11 Mar 2023 12:51:09 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:51971 Mon 25 Sep 2023 10:23:50 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:46214 Mon 14 Nov 2022 11:57:51 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:39668 n = 124) and a group with seminal abnormalities (SAG, n = 136). Evaluation included complete physical examination, past medical history, habits and lifestyle factors, two complete seminal analysis with sperm functional tests, serum levels of 25-hydroxy-vitamin D₃(25(OH)VD₃), total and free testosterone, luteinizing hormone (LH), follicle-stimulating hormone (FSH), sex hormone-binding globulin (SHBG), total cholesterol, homeostatic model assessment of insulin resistance (HOMA-IR) index, and karyotype. The mean concentration of 25(OH)VD₃ was significantly lower in the SAG (P < 0.001) and positively correlated with all baseline seminal parameters and total testosterone levels. In addition, serum vitamin D₃ concentration was found to be positively correlated with sperm concentration (β = 2.103; P < 0.001), total number of spermatozoa with progressive motility (β = 2.069; P = 0.003), total number of motile spermatozoa (β = 2.571; P = 0.015), and strict morphology (β = 0.056; P = 0.006), regardless of other variables. This is the first comparative study to address the issue of serum vitamin D₃ content between normozoospermic patients and those with sperm abnormalities. It clearly demonstrates a direct and positive relationship between serum vitamin D level and overall semen quality, male reproductive potential, and testosterone levels.]]> Fri 17 Jun 2022 15:25:05 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:48890 Fri 14 Apr 2023 15:39:31 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:47345 Fri 13 Jan 2023 12:16:37 AEDT ]]>