100 A COMPARISON OF GLYCEROL AND EGTA FOR ULTRARAPID FREEZING OF BULL EPIDIDYMAL SPERM

The ultrarapid freezing technique was developed as an alternative to slow conventional freezing to avoid formation of ice crystals (Tucker MJ and Liebermann J 2007, Vitrification in Assisted Reproduction, 87-92). The recent use of ethylene glycol tetraacetic acid (EGTA) instead of glycerol as a cryoprotectant for sperm is a result of efforts to reduce osmotic and cytotoxic effects. Accordingly, the objective of the present study was to compare the cryoprotective effects of EGTA v. glycerol on bovine sperm frozen using an ultrarapid method. A pool of epididymal sperm collected from 5 bulls was maintained in Botusui extender (Biotech, Botucatu, Brazil) containing 5% BSA, either EGTA (5%) or glycerol (5%), and 0 or 2 mg mL of polyvinyl alcohol (PVA). All samples were loaded into 0.25-mL French straws and either placed into a freezing machine (TK 4000 compacta, TK equipamentos para reproducao, Uberaba, Brazil) and cooled at a rate of 50°C/min, or exposed to liquid nitrogen (LN2) vapor for 5 to 15 min before plunging into LN2. After overnight storage in LN2, straws were thawed and examined using CASA (HTM IVOS 12, Hamilton Thorne Research, Beverly, MA, USA) for total motility (TM), progressive motility (PM), path velocity (VAP), progressive velocity (VSL), and track speed (VCL). Acridine Orange (AO) was used to check DNA integrity of sperm cells (Chirinea VH et al. 2006 Ciencia Animal Brasileira 7, 407-415). Our results indicate that, despite the potentially damaging effects of the extreme temperature changes, epididymal sperm showed 95% of DNA integrity and, therefore, should be able to participate in the fertilization process. Addition of PVA had a negative effect on sperm motility characteristics. CASA revealed that glycerol was a more suitable cryoprotectant for ultrarapid freezing of bull epididymal spermatozoa than was EGTA (see Table 1). Table 1. CAPES.

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Effects of sodium pyruvate on viability, synthesis of reactive oxygen species, lipid peroxidation and DNA integrity of cryopreserved bovine sperm

Animal Reproduction Science ◽

10.1016/j.anireprosci.2017.07.017 ◽

2017 ◽

Vol 185 ◽

pp. 18-27 ◽

Cited By ~ 7

Author(s):

F. Korkmaz ◽

E. Malama ◽

M. Siuda ◽

C. Leiding ◽

H. Bollwein

Keyword(s):

Reactive Oxygen Species ◽

Lipid Peroxidation ◽

Reactive Oxygen ◽

Dna Integrity ◽

Oxygen Species ◽

Sodium Pyruvate ◽

Bovine Sperm

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Brittle fracture of Sn-37Pb solder joints induced by enhanced intermetallic compound growth under extreme temperature changes

Journal of Materials Processing Technology ◽

10.1016/j.jmatprotec.2019.01.006 ◽

2019 ◽

Vol 268 ◽

pp. 1-9 ◽

Cited By ~ 6

Author(s):

Ruyu Tian ◽

Chunjin Hang ◽

Yanhong Tian ◽

Jikai Xu

Keyword(s):

Intermetallic Compound ◽

Brittle Fracture ◽

Solder Joints ◽

Extreme Temperature ◽

Temperature Changes ◽

Intermetallic Compound Growth

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Vitamin D3 treatment regulates apoptosis, antioxidant defense system, and DNA integrity in the epididymal sperm of an aged rat model

Molecular Reproduction and Development ◽

10.1002/mrd.23280 ◽

2019 ◽

Vol 86 (12) ◽

pp. 1951-1962 ◽

Cited By ~ 1

Author(s):

Malsawmhriatzuala Jeremy ◽

Guruswami Gurusubramanian ◽

Vikas Kumar Roy

Keyword(s):

Vitamin D3 ◽

Rat Model ◽

Antioxidant Defense ◽

Antioxidant Defense System ◽

Dna Integrity ◽

Defense System ◽

Epididymal Sperm ◽

Aged Rat

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3 SELECTION OF UNFRAGMENTED-DNA SPERMATOZOA FROM HEAT STRESSED MICE BY FEMALE UTERINE TRACT AND ZONA PELUCIDA BINDING

Reproduction Fertility and Development ◽

10.1071/rdv21n1ab3 ◽

2009 ◽

Vol 21 (1) ◽

pp. 102

Author(s):

J. D. Hourcade ◽

M. Perez-Crespo ◽

B. Pintado ◽

A. Gutiérrez-Adán

Keyword(s):

Heat Treatment ◽

Dna Damage ◽

Sperm Motility ◽

Tail Length ◽

Dna Integrity ◽

Sperm Selection ◽

Epididymal Sperm ◽

Cleavage Rate ◽

Sperm Dna ◽

Selection Of

Physiological bases of the sperm selection processes within the female reproductive tract before they meet and fertilize the oocyte are unknown. The aim of this work was to determine if one of the keys of spermatozoa selection could be DNA integrity. It has been reported that sperm DNA damage does not impair in vitro fertilization (IVF). However, it has been suggested that the zona pelucida (ZP) is able to select spermatozoa with unfragmented DNA (Liu and Baker 2007 Hum. Reprod. 22, 1597–1602). In this work, DNA damage of spermatozoa was artificially induced by scrotal heat treatment (HT) (42°C, 30 min). Twenty-one days after the HT, spermatozoa were recovered from the epididymis caudae of CD1 mice and from the uterine horns near the cervix (Uc), from the uterine horns near the oviducts (Uo), and from the oviducts (Ov) of CD1 females 1–2 h after mating with HT and control males. In each region we determined numbers of spermatozoa, individual motility and sperm DNA integrity by COMET assay (% DNA in tail, tail length, and COMET moment was calculated). Also, females naturally mated either with HT or control males were killed at Day 14 of pregnancy, and number of foetuses and resorptions was recorded. Additionally, IVF was performed with epididymal sperm from HT or control males, Two hours after IVF attached and un-attached spermatozoa to the ZP were recovered and samples were evaluated for sperm motility (CASA), sperm zona-binding, and sperm DNA fragmentation (COMET). Also cleavage rate of fertilized oocytes with sperm from HT or control males was analyzed. One-way ANOVA was used to compare the results form each group. Epididymal sperm count (12*106 and 4.4*106 for control and HT respectively), sperm motility (75 and 21% respectively) and testis weight (133.90 and 68.76 mg, respectively) were significantly reduced after heat treatment (P < 0.001). For the heat treatment, COMET values decreased significantly during the transit from Uc to Uo and from Uo to Ov (Tail DNA: 25.7, 23.5, and 14.4% respectively, P < 0.01; Tail length: 38.4, 29.4, and 11.2 pixels, P < 0.001; COMET Moment: 12.5, 8.5, and 2 respectively, P < 0.001). Heat treatment reduced numbers of foetuses (7 ± 0.5 v. 5 ± 0.49, control and HT group, respectively), but number of resorptions was not altered. Spermatozoa bound per ZP in IVF experiments (55 ± 7 and 13 ± 6, control and HT, respectively) and cleavage rate (61 ± 1 v. 15 ± 6, control and HT, respectively) were significantly reduced in the HT group. Two hours after IVF, spermatozoa attached to the ZP in HT group showed a significant decrease in COMET parameters as in tail length (59.46 ± 2.895 v. 34.66 ± 3.531), and in tail moment compared with unattached spermatozoa. Our results indicate that DNA integrity sperm selection mechanisms are present in both the female tract and the ZP. We suggest that genital tract and sperm-ZP binding process plays an important role in selection of sperm with normal chromatin DNA.

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95 THE EFFECT OF FREEZING TECHNIQUES ON QUALITY OF CAT TESTICULAR SPERM

Reproduction Fertility and Development ◽

10.1071/rdv23n1ab95 ◽

2011 ◽

Vol 23 (1) ◽

pp. 153

Author(s):

M. Techakumphu ◽

S. Buarpung ◽

T. Tharasanit

Keyword(s):

Testicular Tissue ◽

Conventional Technique ◽

Domestic Cat ◽

Control Group ◽

Dna Integrity ◽

Testicular Sperm ◽

Different Types ◽

Senior Research ◽

Conventional Freezing

Cryopreservation of testicular tissue is beneficial for valuable animals that die unexpectedly or when elective castration is required. Until recently, knowledge regarding cryopreservation of testicular tissue/sperm in the domestic cat has been limited. The objective of this study was to determine the effects of freezing techniques and cryoprotectants on quality of testicular sperm. In Experiment 1, each testis was cut into 10 equal small pieces (∼2 × 3 × 5 mm) and cryopreserved in freezing medium containing with 5% (v/v) glycerol using conventional (10 min in liquid nitrogen vapors) or controlled-rate freezing techniques. In Experiment 2, testicular tissues were conventionally frozen with different types of 5% (v/v) cryoprotectants [glycerol (Gly), dimethylsulphoxide (DMSO), 1,2-propanediol (PrOH), or ethylene glycol (EG)]. Non-cryopreserved testicular sperm was used as a control. After thawing, testicular sperm were extracted and examined for viability and DNA integrity using non-membrane-permeable DNA staining (Ethidium homodimer-1) and TUNEL assay, respectively. Viability of testicular sperm cryopreserved by controlled-rate cryopreservation (45.9 ± 3.7) was significantly lower than non-frozen control (60.3 ± 0.9) and conventional freezing technique (55.0 ± 2.7). Gly (58.2 ± 2.6) and EG (53.3 ± 2.3) yielded a similar viability compared with non-frozen control (P > 0.05), whereas DMSO and PrOH demonstrated an inferior cryoprotectant for feline testicular sperm (% viability for DMSO and PrOH: 46.3 ± 3.3 and 44.3 ± 2.9, respectively). In both experiments, DNA integrity of frozen–thawed testicular sperm did not significantly differ from the control group. In conclusion, cat testicular tissue can be frozen as small pieces using both conventional technique and controlled rate freezing. However, freezing technique and type of cryoprotectant markedly affect the post-thawed quality of testicular sperm. Further study requires examination of the optimal cooling rate during cryopreservation and also the fertilizability of frozen–thawed testicular sperm. This study was financially supported by CHE-TRF Senior Research Scholars RTA-5080010.

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Assessment of binder of sperm protein 1 (BSP1) and heparin effects on in vitro capacitation and fertilization of bovine ejaculated and epididymal sperm

Zygote ◽

10.1017/s0967199420000374 ◽

2020 ◽

Vol 28 (6) ◽

pp. 489-494

Author(s):

Paula Rodríguez-Villamil ◽

Daiane Mentz ◽

Felipe Ledur Ongaratto ◽

Luis Henrique Aguiar ◽

Jose Luiz Rodrigues ◽

...

Keyword(s):

Control Group ◽

Sperm Capacitation ◽

Epididymal Sperm ◽

Sperm Protein ◽

Fertilization Rates ◽

Bovine Sperm ◽

Development Rates ◽

Developmental Rates

SummaryThe present study evaluated the effect of binder of sperm protein 1 (BSP1) and/or heparin on in vitro bovine capacitation and fertilization rates using epididymal and ejaculated bovine sperm. Frozen–thawed sperm were selected and used in the following treatments. Control group: Fert-TALP medium without heparin; heparin (HEP) group: Fert-TALP with heparin (10 UI/ml); BSP1 group: Fert-TALP medium with BSP1 (10 µg/ml for ejaculated sperm; 40 µg/ml for epididymal sperm); HEP + BSP1 group: Fert-TALP medium with heparin (5 UI/ml) and BSP1 (5 µg/ml for ejaculated sperm; 20 µg/ml for epididymal sperm) and determined in vitro capacitation rates in different interval times (0, 15, 30 and 60 min) using the chlortetracycline ﬂuorescence (CTC) method. Also, we evaluated the development rates of oocytes fertilized with ejaculated or epididymal sperm into the same treatments. Capacitation was greater and faster when ejaculated sperm were treated for 60 min with heparin compared with other treatments. However, developmental rates were similar in all treatments. For epididymal sperm, the treatments with BSP1 presented higher capacitation and fertilization rates compared with heparin (P < 0.05). The effects of heparin + BSP1 on capacitation and developmental rates did not cause any increase in capacitation or blastocyst rates compared with other groups for ejaculated or epididymal sperm. In conclusion, this study confirmed that either BSP1 and heparin can be used as capacitator agents for bovine ejaculated sperm during IVF. However, BSP1 seems to be more efficient compared with heparin for epididymal sperm. Furthermore, BSP1 and heparin have no synergic effects on sperm capacitation.

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Effects of Urbanization on Regional Extreme-Temperature Changes in China, 1960–2016

Sustainability ◽

10.3390/su12166560 ◽

2020 ◽

Vol 12 (16) ◽

pp. 6560 ◽

Cited By ~ 1

Author(s):

Junliang Qiu ◽

Xiankun Yang ◽

Bowen Cao ◽

Zhilong Chen ◽

Yuxuan Li

Keyword(s):

Northeast China ◽

Urban Climate ◽

Extreme Temperature ◽

Maximum Temperature ◽

Temperature Changes ◽

Low Latitudes ◽

Different Seasons ◽

Extreme Minimum Temperature ◽

Temperature Indices ◽

Urbanization In China

Urbanization in China has been expanding dramatically since 1978, significantly affecting the extreme temperature changes in cities, which is a vital indicator of urban climate change. To assess urban-related effect on regional extreme-temperature changes in China, this study employed high-resolution land use data to divide meteorological stations into rural stations, suburban stations, and urban stations, and evaluated the annual and seasonal changes in extreme minimum temperature (TNN), mean temperature (Tavg) and extreme maximum temperature (TXX) at each meteorological station. The result revealed that extreme temperature indices (TNN, TXX) and Tavg increased significantly from 1960 to 2016 with varied degrees in different seasons and different regions. Extreme temperature indices in high latitudes increased more rapidly than in low latitudes; while the trends in summer are slower than in other seasons. Urbanization effects on the trends of TNN, Tavg and TXX were all statistically significant, but urbanization effects on TNN and Tavg were more significant than TXX. The urbanization effects were more significant in low altitudes, especially in North, South, Northwest and Northeast China. In North, Northwest and Northeast China, the urban-related effects on temperature increase were mainly observed in spring and winter, but in South China, the urban-related effects were more evident in summer. This study is valuable for sustainable urban planning in China.

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Attribution of extreme temperature changes during 1951–2010

Climate Dynamics ◽

10.1007/s00382-015-2674-2 ◽

2015 ◽

Vol 46 (5-6) ◽

pp. 1769-1782 ◽

Cited By ~ 40

Author(s):

Yeon-Hee Kim ◽

Seung-Ki Min ◽

Xuebin Zhang ◽

Francis Zwiers ◽

Lisa V. Alexander ◽

...

Keyword(s):

Extreme Temperature ◽

Temperature Changes

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Effect of Extreme Temperature on the Performance of Wind Turbine Blade

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.522.457 ◽

2012 ◽

Vol 522 ◽

pp. 457-461

Author(s):

Jia Yang ◽

Wen Jun Qi

Keyword(s):

Wind Turbine ◽

Turbine Blade ◽

Interaction Analysis ◽

Extreme Temperature ◽

Weather Conditions ◽

Wind Turbine Blade ◽

Temperature Changes ◽

Performance Change ◽

Aerodynamic Temperature ◽

Temperature Loads

According to the Dabancheng wing farm weather conditions from 1971 to 2000, and its extreme temperature conditions, the performance change of 750KW wind turbine blade with them was researched in the article. Import UG Modeling to ANSYS, then achieve the static structural analysis and the heat-structure interaction analysis respectively. The results show that comparing aerodynamic-temperature loads with aerodynamic loads, the stress, strain and displacement of the blade is increased by 13.89%, 10.29% and 0.20%. Therefore, temperature changes have a certain impact on the blade performance. In the future, the temperature will be a necessary consideration during design of blade structure.

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