• Title/Summary/Keyword: cryo-damage

Search Result 12, Processing Time 0.025 seconds

Cryo-SEM Methodology of Arabidopsis thaliana Stem Using High-Pressure Freezing (고압동결고정을 이용한 애기장대 줄기의 cryo-SEM 분석법)

  • Choi, Yun-Joung;Lee, Kyung-Hwan;Je, A-Reum;Chae, Hee-Su;Jang, Ji-Hoon;Lee, Eun-Ji;Kweon, Hee-Seok
    • Applied Microscopy
    • /
    • v.42 no.2
    • /
    • pp.111-114
    • /
    • 2012
  • The scanning electron microscopy is an ideal technique for examining plant surface at high resolution. Most hydrate samples, however, must be fix and dehydrate for observation in the scanning electron microscope. Because the microscopes operate under high vacuum, most specimens, especially biological samples, cannot withstand water removal by the vacuum system without morphological distortion. Cryo-techniques can observe in their original morphology and structure without various artifacts from conventional sample preparation. Rapid cooling is the method of choice for preparing plant samples for scanning electron microscopy in a defined physiological state. As one of cryo-technique, high-pressure freezing allows for fixation of native non-pretreated samples up to $200{\mu}M$ thick and 2 mm wide with minimal or no ice crystal damage for the freezing procedure. In this study, we could design to optimize structural preservation and imaging by comparing cryo-SEM and convention SEM preparation, and observe a fine, well preserved Arabidopsis stem's inner ultrastructure using HPF and cryo-SEM. These results would suggest a useful method of cryo-preparation and cryo-SEM for plant tissues, especially intratubule and vacuole rich structure.

Methodologies for Cryopreservation of Mammalian Germline Cells and Tissues

  • Karmakar, Polash Chandra;Jung, Sang-Eun;Ryu, Buom-Yong
    • Reproductive and Developmental Biology
    • /
    • v.41 no.2
    • /
    • pp.41-50
    • /
    • 2017
  • Until today, success in germline cells and tissue cryopreservation is limited mainly due to the poor understanding of the complex physiological processes can lead to cell damage during cryopreservation. Germline cells, from both male and female, have unique ability to differentiate into one or more cell lines and thus it becomes a crucial point to store them in subzero temperature with the minimal damage of their functional properties and maximum recovery of unchanged and viable cells when thawed. In the past three decades, a vast research has been performed using various different animal models which in fact have led to development of new methodologies and optimization of older one. However, successful use of animal model has provided the opportunity in research with human germline cells and tissues preservation, but not in all the cases. Therefore, the use of new cryo-protective chemicals and modified protocols have been often found in different groups of researchers based on the types, physical structures, utility and animal species of the specimens to be cryopreserved. This review discusses about the basics of different types of cryopreservation methodologies and commonly used optimized protocols and cryoprotectants for germline cells and tissues preservation.

Superconducting high gradient magnetic separation for magnetic substance at sludge powder of hot rolled coolant

  • Kwon, Jun-Mo;Ha, Dong-Woo;Kim, Tae-Hyung;Cho, Mun-Dak;Choi, Woo-Hyuk
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2009.06a
    • /
    • pp.353-353
    • /
    • 2009
  • It is an important task to construct a recycling society with a low damage on the environment in our century. Magnetic separation is expected to be applied for the industrial waste treatment as an important supporting technology. In the magnetic separation of dry condition, the cohesive force between particles is strong compared with that in the wet condition's magnetic separation. The use of high magnetic field by the superconducting magnet enhances the powder's magnetic substance capture ability of the magnetic separation. In this study, the POSCO's coolant sludge of hot rolled steel was used for the superconducting magnetic separation of dry condition. Cryo-cooled NB-Ti superconducting magnet with 100 mm room temperature bore and 600 mm of height was used for magnetic separator.

  • PDF

Effect of Cholesterol Supplementation in Freezing Medium on the Survival and Integrity of Human Sperm after Cryopreservation (콜레스테롤이 동결-해동 후 인간정자의 생존과 기능보존에 미치는 영향)

  • Lim, Jung-Jin;Sung, Su-Ye;Kim, Kye-Seong;Song, Seung-Hon;Lee, Woo-Sik;Yoon, Tae-Ki;Lee, Dong-Ryul
    • Clinical and Experimental Reproductive Medicine
    • /
    • v.35 no.3
    • /
    • pp.203-212
    • /
    • 2008
  • Objective: During cryopreservation process, cold shock and cryo-injury affect the fertilizing capacity of the sperm by damaging cell membranes with loss of functional integrity. A longstanding concept for preventing the cryo-damage is to stabilize the plasma membrane by incorporating cholesterol. This study was to determine the effects of cholesterol in freezing media on the motility and functional integrity of human sperm after cryopreservation. Methods: Control group (non-cholesterol treated) and different concentrations of cholesterol-treated sperm (14 healthy males) were frozen and thawed. After freezing and thawing of sperm, the quality of sperm was evaluated by sperm analysis, acrosome reaction test and sperm chromatin structure assay. Results: When human sperm were incubated in sperm freezing medium (SFM) containing $0.5{\mu}g$ cholesterol and then freezing/thawing, the motility of sperm have significantly improved compared to those untreated cholesterol ($33.46{\pm}1.48%$ vs. $30.10{\pm}1.07%$, p<0.05). The rate of calcium ionophore-induced acrosome reactions in post-thawed sperm was significantly higher than that ($53.60{\pm}1.60%$ vs. $47.40{\pm}1.86%$, p<0.05) in SFM containing cholesterol. Sperm chromatin structure assay revealed that DNA damage to the sperm in the cholesterol-treated group was lower than that of non-treated group. Conclusion: These results suggest that increased cholesterol content of sperm plasma membrane by supplementation of cholesterol in SFM improves sperm motility, capacitation status, and DNA integrity. Therefore, addition of cholesterol into SFM could be a useful for protecting human sperm from cold shock and cryo-injury during cryopreservation.

Percutaneous Cryo-Rhizotomy -A case report- (경피적 냉동요법을 이용한 척수신경 파괴술 -증례 보고-)

  • Lee, Sang-Chul;Yoon, Hea-Jo;Park, So-Young;Yoon, Mi-Ja;Ahn, Woen-Sik;Kim, Seong-Deok
    • The Korean Journal of Pain
    • /
    • v.11 no.1
    • /
    • pp.127-129
    • /
    • 1998
  • Intractable chest and abdominal wall pain responds well to root surgery. But it is better to perform this procedure less invasively with less complications. Cryoanalgesia has been developed to relieve several neurogenic pain without causing irrversible nerve damage. Well-selected percutaneous cryoablative procedure could be one of the technique of choice for some chronic pains because it has the advantage of easy application without any remarkable side effect. We did percutaneous cryoneurolysis of the spinal nerve root at the thoracic level to treat one patient with severe cancer pain on the chest wall(T4, 5, and 8 dermatomes) after successful percutaneous radiofrequency T6 and T7 posterior root rhizotomy. This procedure was performed under fluoroscopic guidance. We advanced 2 mm cryoprobe to the posterior, superior aspect of vertebral foramen on lateral view until the patient felt paresthesia. 3 times of 2 minutes freezing was applied to each spinal nerve root. The patient got immediate pain relief without any side effect.

  • PDF

Is optimal cutting temperature compound essential embedding solution treatment to cryo-sectioning of brain tissue?

  • Baek, Hye Kyung;Song, Ji Ae;Yi, Sun Shin
    • Korean Journal of Veterinary Research
    • /
    • v.56 no.2
    • /
    • pp.85-89
    • /
    • 2016
  • We tested a set of conditions for obtaining optimal tissue quality in preparation for histology in samples of mouse brain. C57BL/6J mice were sacrificed and perfused with 4% paraformaldehyde, after which the brains were removed and dehydrated in 30% sucrose solution. The brains were then divided into four groups according to freezing temperature and usage of optimal cutting temperature (OCT) compound. Next, we stained the sectioned brain tissues with Harris hematoxylin and eosin Y and immunohistochemistry was performed for doublecortin. The best quality tissue was obtained at $-25^{\circ}C$ and by not embedding with the OCT compound. When frozen at $-25^{\circ}C$, the embedded tissue was significantly damaged by crystals, while at $-80^{\circ}C$ there were no meaningful differences between qualities of embedded- and non-embedded tissues. Overall, we identified a set of conditions to obtain quality frozen brain sections. Our developed protocol will help resolve matters associated with damage caused to sectioned brain tissue by crystal formation during freezing.

Supplementation of cryoprotective extender with resveratrol decreases apoptosis index and reactive oxygen species levels in post-thaw dog sperm

  • Bang, Seonggyu;Tanga, Bereket Molla;Qamar, Ahmad Yar;Fang, Xun;Seong, Gyeonghwan;Nabeel, Abdelbagi Hamad Talha;Yu, Iljeoung;Cho, Jongki
    • Korean Journal of Veterinary Research
    • /
    • v.61 no.4
    • /
    • pp.29.1-29.7
    • /
    • 2021
  • Resveratrol (RSV, 3,5,4'-trihydroxytrans-stilbene) protects sperm from cryo-induced damage in various animal and human species. In this study, we aimed to assess the effect of dog sperm cryoprotective extender containing RSV on the quality of post-thaw dog sperm. Sperm were collected from 4 Beagles and supplemented with different concentrations of RSV (0, 100, 200, and 400 µM). After thawing, apoptosis index, and reactive oxygen species (ROS) levels were assessed to determine post-thaw sperm quality. Dog sperm cryopreserved with 400 µM RSV showed significant improvement in post-thaw sperm quality with lower apoptosis index and ROS levels (p < 0.05). Our results showed that the supplementation of dog sperm cryoprotective extender with RSV at a concentration of 400 µM improved the post-thaw dog sperm quality in the term of sperm ROS production and apoptosis. In addition, we emphasize the necessity of testing the ROS levels and apoptosis index using flow cytometry to determine the quality of post-thaw semen.

Effects of α-Linolenic Acid in Frozen-thawed Boar Spermatozoa (돼지 정자의 동결보존 시 α-Linolenic Acid의 효과)

  • Lee, Won-Hee;Hwangbo, Yong;Lee, Sang-Hee;Yang, Jin-Woo;Kim, Hwa-Young;Lee, Yu-Rim;Park, Ji-Eun;Cheong, Hee-Tae;Yang, Boo-Keun;Park, Choon-Keun
    • Reproductive and Developmental Biology
    • /
    • v.40 no.3
    • /
    • pp.27-31
    • /
    • 2016
  • The aim of this study was to evaluate effect of ${\alpha}$-linolenic acid (ALA) on viability, acrosome reaction and mitochondrial intact in frozen-thawed boar sperm. The boar semen was collected by gloved-hand method and cryopreserved in 20% egg yolk freezing extender containing ALA (0, 3, 5, and 10 ng/mL) with 0.05% ethanol. The frozen-boar spermatozoa were thawed at $37.5^{\circ}C$ for 45 sec in water-bath. The spermatozoa samples were evaluated the plasma membrane integrity, acrosome reaction, and mitochondrial integrity using flow cytometry. In results, population of live sperm with intact plasma membrane was significantly higher in control and 3 ng/mL ALA treatment group than ethanol group (p<0.05). In contract, dying sperms were higher in ethanol group than 3 ng/mL ALA treatment (p<0.05). Acrosomal membrane damage in all sperm population was reduced in 3 ng/mL ALA groups compared with ethanol treatment (p<0.05). However, acrosome damage in live sperm population was no significant difference among the all treatment groups. Mitochondrial integrity was not influenced by ALA treatments in both of live and all sperm population. In conclusion, this results show that supplement of ALA during the cryopreservation process could reduce the membrane damages including plasma and acrosomal membrane, whereas ALA did not influence to mitochondria in boar spermatozoa. Therefore, these results suggest that ALA can protect against the membrane damage derived cryo-stress, and cryopreservation efficiency of boar semen would be improved by use of ALA.

Effects of α-Linolenic Acid and Bovine Serum Albumin on Frozen-thawed Boar Sperm Quality during Cryopreservation

  • Lee, Won-Hee;Hwangbo, Yong;Lee, Sang-Hee;Cheong, Hee-Tae;Yang, Boo-Keun;Park, Choon-Keun
    • Reproductive and Developmental Biology
    • /
    • v.40 no.4
    • /
    • pp.33-37
    • /
    • 2016
  • This study was conducted to evaluate effect of ${\alpha}$-linolenic acid (ALA) and bovine serum albumin (BSA) on viability, acrosome reaction and mitochondrial intact in frozen-thawed boar sperm. The boar semen was collected by gloved-hand method and cryopreserved using freezing extender containing 3 ng/mL ALA and/or $20\;{\mu}g/mL$ BSA. Cryo-preserved boar sperms were thawed in $37^{\circ}C$ water-bath for 45 sec to analysis. Viability, acrosome reaction, and mitochondrial intact were analyzed using flow cytometry. In results, viability of frozen-thawed boar sperm was significantly higher in only ALA+BSA supplement group than control group (p<0.05), whereas there was no difference either in ALA or BSA supplement. However, acrosome reacted sperm in both of live and all sperm population were significantly decreased in all treatment groups than control (p<0.05). Interestingly, mitochondrial intact of boar sperm was enhanced in ALA and ALA+BSA groups compared with control (p<0.05). In this study, we showed that supplementation of ALA and BSA in freezing extender enhanced the sperm viability, mitochondrial intact and decrease acrosomal membrane damage. In conclusion, our findings suggest that quality of frozen-thawed sperm in mammalians could improve by using of ALA and BSA.