scholarly journals Cryopreservation of Tomato Pollen

HortScience ◽  
1995 ◽  
Vol 30 (4) ◽  
pp. 797A-797 ◽  
Author(s):  
E.J. Sacks ◽  
D.A. St. Clair
Keyword(s):  
Lycopersicon Esculentum ◽  
Plant Breeding ◽  
Calcium Sulfate ◽  
Germplasm Conservation ◽  
Freezing And Thawing ◽  
Tissue Paper ◽  
Anhydrous Calcium Sulfate ◽  
Glass Tubes ◽  
Fresh Pollen

We have developed a method for cryopreserving Lycopersicon esculentum pollen to facilitate the timing of crosses and for long-term germplasm conservation. Gelatin capsules containing pollen were wrapped in tissue paper and placed in air-tight glass tubes with anhydrous calcium sulfate desiccant. Tubes containing pollen were stored at –80C. In one experiment, we stored the pollen of LA359 and T5 at –80C for 37 days. Pollen predesiccated overnight at 4C then stored at –80C, pollen put in a tube with desiccant then immediately stored at –80C, and fresh pollen were compared by pollinating 10 flowers of LA359 with each of the six pollen treatments and counting the number of seed per fruit. Average seed counts ranged from 127 for fresh, T5 pollen to 172 for predesiccated LA359 pollen. In another experiment, cryopreserved pollen of UC82B and VFNT Cherry was given from 0 to 6 cycles of freezing and thawing. Ten flowers of LA359 were pollinated with each of the 12 treatments. Average seed counts ranged from 125 to 152. The data from both experiments suggest that cryopreservation of tomato pollen to facilitate efficient plant breeding is feasible.

scholarly journals 1005 Antibiotic-Impregnated Calcium Sulfate Beads Are Not Effective in the Primary Prevention of Infection in Open Femur and Tibia Fractures

2021 ◽  
Vol 108 (Supplement_2) ◽  
Author(s):  
A Fung ◽  
A Ward ◽  
K Patel ◽  
M Krkovic
Keyword(s):  
Primary Prevention ◽  
Infection Rate ◽  
Calcium Sulfate ◽  
Acute Infection ◽  
Open Fractures ◽  
Prevention Of Infection ◽  
Significant Difference ◽  
Tibia Fractures ◽  
Systemic Antibiotics

Abstract Introduction Infection is a major complication of open fractures. Antibiotic-impregnated calcium sulfate (AICS) beads are widely used as an adjuvant to systemic antibiotics. Whilst their efficacy in the secondary prevention of infection is established, we present the first retrospective study evaluating AICS beads in the primary prevention of infection in open fractures. Method 214 open femur and tibia fractures in 207 patients were reviewed over a seven-year period. 148 fractures received only systemic antibiotic prophylaxis. 66 fractures also received AICS beads. The occurrence of acute infection (wound infection and acute osteomyelitis) was recorded, as well as that of long-term complications (chronic osteomyelitis, non-union and death). Results Fractures that received AICS with systemic antibiotics had an overall acute infection rate of 42% (28/66), compared to 43% (63/148) in fractures that received only systemic antibiotics (p > 0.05). There was no significant difference in infection rate even when fractures were stratified by Gustilo-Anderson grade. There was also no significant difference in the rate of long-term complications. Conclusions Our results indicate that the adjuvant use of AICS beads is not effective for the primary prevention of acute infection or long-term complications in open leg fractures. Further research is needed to elucidate the factors influencing the outcomes of AICS use.

Geothermal modeling of soil or mine tailings with concurrent freezing and deposition

1998 ◽  
Vol 35 (2) ◽  
pp. 234-250 ◽  
Author(s):  
JF (Derick) Nixon ◽  
Nick Holl
Keyword(s):  
Snow Cover ◽  
Mine Tailings ◽  
Frozen Soil ◽  
Freezing And Thawing ◽  
Frozen Ground ◽  
Geothermal Model ◽  
Winter Time ◽  
Upper Boundary ◽  
Good Agreement

A geothermal model is described that simulates simultaneous deposition, freezing, and thawing of mine tailings or sequentially placed layers of embankment soil. When layers of soil or mine tailings are placed during winter subfreezing conditions, frozen layers are formed in the soil profile that may persist with time. The following summer, warmer soil placement may not be sufficient to thaw out layers from the preceding winter. Remnant frozen soil layers may persist for many years or decades. The analysis is unique, as it involves a moving upper boundary and different surface snow cover functions applied in winter time. The model is calibrated based on two uranium mines in northern Saskatchewan. The Rabbit Lake scenario involves tailings growth to a height of 120 m over a period of 24 years. At Key Lake, tailings increase in height at a rate of 1.3 m/year. Good agreement between the observed position of frozen layers and those predicted by the model is obtained. Long-term predictions indicate that from 80 to 200 years would be required to thaw out the frozen layers formed during placement, assuming 1992 placement conditions continue. Deposition rates of 1.5-3 m/year give the largest amounts of frozen ground. The amount of frozen ground is sensitive to the assumed snow cover function during winter.Key words: geothermal, model, tailings, freezing, deposition.

scholarly journals Impact of freezing and thawing of human ovarian tissue on follicular growth after long-term xenotransplantation

2011 ◽  
Vol 28 (12) ◽  
pp. 1157-1165 ◽  
Author(s):  
Christiani A. Amorim ◽  
Anu David ◽  
Marie-Madeleine Dolmans ◽  
Alessandra Camboni ◽  
Jacques Donnez ◽  
...  
Keyword(s):  
Ovarian Tissue ◽  
Follicular Growth ◽  
Freezing And Thawing ◽  
Human Ovarian Tissue

scholarly journals Cryopreservation: The secret of modern preservation of brewer’s yeasts – minireview

2021 ◽  
Vol 67 (1) ◽  
pp. 403-408
Author(s):  
Katarína Hanzalíková ◽  
Petra Kubizniakova ◽  
Lucie Kyselová ◽  
Dagmar Matoulková
Keyword(s):  
Cell Damage ◽  
Cellular Structures ◽  
Biological Functions ◽  
Freezing And Thawing ◽  
Thawing Processes ◽  
Thawing Rate ◽  
Brewer’S Yeasts ◽  
Long Term Preservation ◽  
Stress Accumulation

The aim of the long-term preservation of cells, tissues and organs is to maintain their cellular structures and biological functions for as long as possible. Cryopreservation is a process where biological material is stored and preserved at very low temperatures. However, freezing and thawing processes can cause irreversible cell damage, which is related to formation of ice crystals, osmotic stress, accumulation of reactive forms of oxygen, etc. Therefore the cell viability depends mainly on the freezing rate, the composition of the cryoprotective medium as well as on the thawing rate. Using a suitable cryoprotective medium can increase the viability rate of the yeasts after “revitalization“. Appropriate pre-cultivation before freezing also plays an important role. These facts show that cell freezing and thawing processes must be controlled to avoid cell damage.

scholarly journals Cryogenic Storage of Tomato Pollen: Effect on Fecundity

HortScience ◽  
1996 ◽  
Vol 31 (3) ◽  
pp. 447-448 ◽  
Author(s):  
Erik J. Sacks ◽  
Dina A. St. Clair
Keyword(s):  
Lycopersicon Esculentum ◽  
Seed Production ◽  
Fruit Set ◽  
Viable Seed ◽  
Pollen Storage ◽  
Germplasm Storage ◽  
Cryogenic Storage ◽  
Fresh Pollen ◽  
Tomato Breeding ◽  
Pollen Effect

The influence of cryogenic pollen storage on fruit set and seed production in tomato (Lycopersicon esculentum Mill.) was investigated. Flowers pollinated with pollen samples stored for 5 weeks at –80C, with or without 20 h precooling at 4C, had similar fruit set and number of viable seed per fruit as those pollinated with fresh pollen. Pollen samples, which were repeatedly cooled (–80C) and warmed (to 22 to 24C) for up to six cycles, continuously maintained the same viability as the fresh pollen. When cryogenically stored pollen of L. esculentum 2-837, LA359, LA3198, and LA3199 were used to pollinate LA359, the number of viable seed formed per fruit differed significantly. Results of this study suggest that pollen cryopreservation can be used successfully for tomato breeding and germplasm storage.

scholarly journals Personal medicines storage in New Zealand

2013 ◽  
Vol 5 (2) ◽  
pp. 146 ◽  
Author(s):  
Campbell Hewson ◽  
Chong Chi Shen ◽  
Clare Strachan ◽  
Pauline Norris
Keyword(s):  
New Zealand ◽  
Relative Humidity ◽  
Storage Conditions ◽  
Child Safety ◽  
Extreme Temperatures ◽  
Freezing And Thawing ◽  
Data Logger ◽  
Drug Storage ◽  
Storage Methods

INTRODUCTION: Poor storage of medicines can reduce their efficacy, yet little is known about how people store medicines in their homes and elsewhere, why these locations are chosen, and whether the conditions are suitable for medicines storage. AIM: To investigate where medicines are commonly stored in New Zealand households, why, and the typical conditions – temperature and relative humidity – in those places of storage. METHODS: Data from a large qualitative study on the meanings of medicines were analysed to explore where people store medicines in their households, and why. A data logger was used to log temperature and relative humidity in common medicine storage places, such as homes and cars. RESULTS: Kitchens and bathrooms were the most commonly reported storage places, with people influenced by convenience, desire to remember to take medicines, and child safety when deciding where to store medicines. High temperatures and humidity were found in kitchens and bathrooms, extreme temperatures in a car and a backpack, and extremely low temperatures in checked-in luggage on a plane. DISCUSSION: Temperature- and humidity-sensitive medicines should not be stored long-term in common storage locations, such as kitchens and bathrooms. Conditions in these places may not comply with the recommended storage conditions given by the manufacturer. Furthermore, medicines should not be left in backpacks or cars, especially if the vehicle is in the sun. Medicines that may degrade upon freezing and thawing – such as protein-containing medicines, emulsions, suspensions and some solutions – should not be stored in the cargo hold of a plane. KEYWORDS: Drug storage; humidity; New Zealand; temperature

scholarly journals Evaporite weathering and deposition as a long-term climate forcing mechanism

Geology ◽  
2020 ◽  
Author(s):  
Graham A. Shields ◽  
Benjamin J.W. Mills
Keyword(s):  
Calcium Sulfate ◽  
Climate Forcing ◽  
Silicate Weathering ◽  
Carbonate Precipitation ◽  
Sulfate Deposition ◽  
Mutual Dependence ◽  
Carbonate Sedimentation ◽  
Global Cooling ◽  
First Time

Although it is widely accepted that Earth’s long-term surface temperature is regulated by the mutual dependence of silicate weathering and climate on CO2, the root causes of some climatic events remain unresolved. We show here for the first time that imbalances between evaporite weathering and deposition can affect climate through the process of carbonate sedimentation. Calcium sulfate weathering supplies Ca2+ ions to the ocean unaccompanied by carbonate alkalinity, so that increased carbonate precipitation strengthens greenhouse forcing through transfer of CO2 to the atmosphere. Conversely, calcium sulfate deposition weakens greenhouse forcing, while the high depositional rates of evaporite giants may overwhelm the silicate weathering feedback, causing several degrees of planetary cooling. Non-steady-state evaporite dynamics and related feedbacks have hitherto been overlooked as drivers of long-term carbon cycle change. Here, we illustrate the importance of evaporite deposition, in particular, by showing how a series of massive depositional events contributed to global cooling during the mid–late Miocene.

scholarly journals Cryopreservation of boar semen

2020 ◽  
Vol 65 (No. 4) ◽  
pp. 115-123
Author(s):  
Marija Jovičić ◽  
Eva Chmelíková ◽  
Markéta Sedmíková
Keyword(s):  
Animal Species ◽  
Semen Quality ◽  
Egg Yolk ◽  
High Rate ◽  
Freezing And Thawing ◽  
Long Term Storage ◽  
Boar Semen ◽  
Boar Spermatozoa ◽  
Term Storage

Sperm cryopreservation is the best technology for long-term storage of the semen. However, the damage of boar spermatozoa by cryopreservation is more severe than in other animal species and a standardized freezing protocol for efficient cryopreservation has not been established yet. Semen quality and freezability vary greatly between breeds as well as between individual boars and even the season. Boar spermatozoa are sensitive to low temperatures; they sustain damage and a high rate of mortality and freezing/thawing the boar semen may strongly impair the sperm function and decrease the semen quality. The freezability of boar semen can be influenced by a cryopreservation procedure, and also by using various additives to freezing and thawing extenders such as antioxidants. In order to obtain acceptable results after thawing the boar semen, it is necessary to combine an optimal amount of additives (glycerol, egg yolk, sugars, antioxidants), cooling and warming velocities.

Bulk Cryopreservation of Isolated Islets of Langerhans

1996 ◽  
Vol 5 (3) ◽  
pp. 395-404 ◽  
Author(s):  
Jonathan R.T. Lakey ◽  
Garth L. Warnock ◽  
Ziliang Ao ◽  
Ray V. Rajotte
Keyword(s):  
Islets Of Langerhans ◽  
Stimulation Index ◽  
Glass Tube ◽  
Human Islets ◽  
Isolated Islets ◽  
Freezing And Thawing ◽  
Slow Cooling ◽  
Glass Tubes ◽  
Multiple Donors

Current methods to isolate human islets of Langerhans are limited and multiple donors are required for successful reversal of longstanding Type 1 diabetes mellitus. Cryopreservation of isolated islets is an effective method of storing and pooling islets. Current cryopreservation protocols are cumbersome due to current practices of placing small aliquots of islets per individual freezer tube. In the present study, we examined the application of a blood freezer bag for the cryopreservation of isolated islets by slow cooling and rapid thawing. Freezing and thawing profiles generated using thermocouples placed inside a 500 mL Cryocyte (Baxter) blood freezer bag showed that a longer equilibration period at −7.4°C was necessary to consistently achieve nucleation and cooling profiles similar to those observed in glass tubes. When known numbers of rat islets were placed in the freezer bag and the cryoprotectant dimethyl sulfoxide (DMSO) was added in a stepwise fashion and removed using a sucrose dilution, the islet recovery compared with glass tubes was 92 ± 4.8 vs. 90 ± 2.3% (n = 4, p = ns, Mann-Whitney U-test). When purified canine islets were cryopreserved in a single freezer bag or in multiple glass tubes, the recovery was similar (78.8 ± 12.5% recovery for freezer bag vs. 82.3 ± 5.3% for glass tubes; n = 6, p = ns). In vitro function was equivalent for both groups. The stimulation index of insulin release during glucose perifusion (stimulated over basal insulin secretion) for canine islets cryopreserved in a freezer bag vs. glass tubes was 3.2 ± 1.0 and 2.3 ± 1.3, respectively (n = 6, p = ns). These values were significantly lower than the nonfrozen control islets (6.9 ± 2.4, p < 0.05). When 2000 canine islets cryopreserved in either a freezer bag, or glass tubes were transplanted into diabetic nude mice, the animals became and remained normoglycemic posttransplant. We conclude that the survival of freshly isolated canine islets cryopreserved in a single freezer bag is equivalent to the glass tube method. Bulk cryopreservation of islets in a single freezer bag will facilitate effective low temperature tissue banking to support ongoing clinical trials of islet transplantation.

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