This is due to the contribution of water to the plasticizing of the amaranth flour film in the presence of glycerol. As can be seen in Fig. 2, the experimental data are well fitted

by the GAB model. The monolayer water content value (mo) of the plasticizer types are significantly different (P < 0.05). This value is higher for glycerol films (0.0712 g water/g dry solids) compared to the sorbitol films (0.0482 g water/g dry solids). This result suggests that the hydrophilic groups of the starch and protein present in the amaranth flour are less available for interaction Tofacitinib with water molecules in the presence of sorbitol. The water molecules, in turn, may be linked to sorbitol, forming the film matrix. This evidences that sorbitol has greater compatibility with the polymers present in the flour, thereby strongly interacting with these macromolecules. Moreover, the mo values found in this study are in agreement with literature values reported for cassava starch films using glycerol and sorbitol as plasticizers ( Mali et al., 2005 and Müller et al., 2008). Veliparib research buy As shown in Table 4,

there are no significant differences (P > 0.05) between glycerol and sorbitol films in terms of water vapor permeability, while the oxygen permeability (OP) is significantly different (P < 0.05). Sorbitol films display lower oxygen permeability compared to glycerol films. In the case of the whey protein film, it has also been observed that the films prepared with sorbitol were less permeable to oxygen than the films prepared with glycerol, even at higher sorbitol concentrations ( McHugh & Krochta, 1994). These results reveal that a less dense and more disorganized polymeric matrix is formed in the presence of glycerol, allowing for greater oxygen diffusion through the film. The microstructures of the glycerol

and sorbitol films analyzed by TEM are presented in Fig. 3. Both films present porous internal microstructure. These pores probably constitute plasticization zones distributed within the film matrix. The microstructure of the flour films also reveals that the protein forms aggregates (black structure), which interacts with the lipid globules within a continuous Florfenicol and more dense matrix formed by the starch (gray structure). It is also noteworthy that the size of lipids globules is more homogeneous and better distributed within the film matrix in the presence of sorbitol (Fig. 3b). Thus, the amaranth flour film plasticized with sorbitol presents a more ordered and homogeneous structure compared to the films plasticized with glycerol (Fig. 3a), leading to films with lower oxygen permeability and mechanical strength. The optimal formulations for the production of amaranth flour films with good mechanical properties and low solubility were Cg 20.02 g glycerol/100 g flour and Tp 75 °C for glycerol films, and Cs 29.5 g sorbitol/100 g flour and Tp 75 °C for sorbitol films.

The authors thank Geert Gijs, crisis coordinator of the FPS Health, Food Chain Safety and Environment, and his team for the logistical organization of the study. The authors are grateful to Wesley Van Dessel and Jan Eyckmans, respective heads of the communication Erastin datasheet services of the WIV-ISP and of the FSP Health, Food Chain Safety and Environment,

and their team members, for the continuous support in the communication of the study and its results. The authors also want to thank Stéphanie Fraselle and her colleagues for the preparation of the blood samples before sending them to the German labs. Finally, the authors thank Sabine Janssens and Tadek Krzywania and his team (WIV-ISP) for the enormous efforts with regard to data input, data processing and administrative support. “
“Hydrogen sulphide is a toxic gas generated by non-specific and anaerobic bacterial reduction of sulphates and sulphur-containing organic compounds. Natural sources include crude petroleum, natural gas, volcanic gases and hot springs. It can also be found in groundwater and released from stagnant or polluted waters and manure or coal pits. The principal industrial source of hydrogen sulphide is recovery as a by-product in the purification

of natural and refinery gases. It is also a by-product of pulp and paper manufacturing and carbon disulphide production. It is used as an intermediate Ion Channel Ligand Library in manufacturing processes (e.g. sulphuric acid) (WHO, 2003). In the UK, regulations are in force requiring storage of slurry (including manure) in certain areas to prevent water pollution (DEFRA, 2010). Similarly, the UK Government is committed to increasing energy production through anaerobic digestion (DEFRA, 2011). These factors have increased potential exposures to hydrogen sulphide in the UK. Human exposure to exogenous PJ34 HCl hydrogen sulphide is principally via inhalation with rapid absorption. Hydrogen sulphide is metabolised through three

pathways: oxidation, methylation, and reactions with metalloproteins or disulphide-containing proteins. Oxidation in the liver is the major detoxification pathway, forming thiosulphate, which is then converted to sulphate and excreted in the urine. The methylation pathway also serves as a detoxification route. The toxicity of hydrogen sulphide is a result of its reaction with key metabolic metalloenzymes. In the mitochondria, cytochrome oxidase (the final enzyme in the respiratory chain) is inhibited by hydrogen sulphide. This disrupts the electron transport chain and impairs oxidative metabolism which particularly impacts nervous and cardiac tissues (both are tissues with high oxygen demand and rely on oxidative metabolism). In the central nervous system, this effect may result in unconsciousness or even death from respiratory arrest (WHO, 2003).

Trade wind effects on vegetation are well documented. For example, they generate distinct microclimates on leeward and adjacent winward sides MEK inhibitor cancer of mountains (Smith and Young, 1987), resulting in longitudinal rainshadow gradients along which the altitudinal limits of vegetation belts vary (e.g. Sklenář and Laegaard, 2003). Low precipitation levels combined with (1) the absence of water input provided by durable snowbeds and (2) well-documented water

stress due to reduction in soil depth and organic matter content at high elevation (Pérez, 1987b, Körner, 2003 and Anthelme et al., 2012) make tropical mountains more arid than their extratropical counterparts (Leuschner, 2000). This is illustrated by the occurrence of ‘alpine deserts’ on the leeward slopes of high isolated

mountains such as Mount Kilimanjaro in East Africa (Crawford, 2008), Mount Chimborazo in Ecuador (Sklenář and Laegaard, 2003), Cordillera de Merida in Venezuela (Monasterio, check details 1979 and Pérez, 1987a), Mount Cameroon (Letouzey, 1985), volcano Maui in Hawaii (e.g. Pérez, 2003), or in large plateaux bordered to the East by high mountain ranges, such as the Bolivian altiplano (Herzog, 1923). The relative aridity observed in TAE is likely responsible for the common occurrence of (1) scleromorphic plant types such as giant cushions, giant rosettes, and microphyllous shrubs (Ramsay and Oxley, 1997 and Leuschner, 2000) and (2) natural and man-induced fire episodes which constitute severe constraints for plant development (Smith and Young, 1987 and Luteyn, 1999). Altitudinal variation is a powerful proxy of the main drivers of the spatiotemporal dynamics of alpine ecosystems (Körner, 2007 and Nagy and Grabherr, 2009). Because of a lower latitudinal position, TAE occur at a much higher altitude than other alpine ecosystems, especially close to the equator (Körner, 2003). Consequently, TAE are exposed to lower partial pressures of atmospheric gases than most extratropical alpine systems, among which low levels of atmospheric CO2 can have a substantial effect on plant growth and biomass (Körner, 2003 and Körner, 2007). For the

same reasons, ultraviolet (UV) radiations are much stronger in TAE (Körner, 2007) and represent a supplementary physical stress for plants (Caldwell and Robberecht, mafosfamide 1980). It is interesting to note that some subtropical, subarctic, and subantarctic isolated islands, as well as New Zealand, share several ecological features with TAE – including similar growth forms such as giant rosettes, giant cushions, and tussock grasses (Halloy and Mark, 1996, Leuschner, 1996, Mark et al., 2000, Bannister et al., 2005 and le Roux and McGeoch, 2010). As these regions do not share necessarily the specific TAE abiotic features of inverted rainfall gradients and high altitude, it seems that the reason for such similarity in vegetation may rely on the strong oceanic influence on the local climate which buffers seasonality (Leuschner, 1996).

, 2008). Herein, all molecules assessed induced caspases activation, with intensification in early and late apoptotic processes. The phosphatidylserine externalization induced at 2 μM is an additional finding that corroborates activation of pathways suggestive of apoptosis. Loss of membrane polarity, GKT137831 ic50 caused by translocation of phosphatidylserine from the inner to outer plasma membrane, thereby exposing phosphatidylserine for

external environment, stimulates recognition and engulfment of dying cells by macrophages and other antigen presenting cells (Kroemer et al., 1997). In order to improve comprehension about cell signaling, it was performed a mitochondrial depolarization analyses. Apoptosis stimulation by the mitochondrial

via starts with a pore formation in the external membrane mitochondrial and release of cytochrome c, with permeability changes and mitochondrial membrane potential collapse. This failure can be measured by cationic lipophilic fluorochromes, such as rhodamine 123 ( de Thonel and Eriksson, 2005). Within 24 h of treatment, α-santonin derivatives learn more did not induce modifications in mitochondrial potential. However, following 48 h, the compound 4 induced mitochondrial depolarization, an indicative of apoptosis intrinsic pathway activation commonly caused in reaction to DNA damage, absence of survivor factors and several types of cellular stress. Whereas caspase-8 was activated, it is likely that it had been occurred

convergence into apoptosis intrinsic pathway downstream from the extrinsic route. Costunolide, a sesquiterpene lactone structure close to α-santonin, induces G2/M cell cycle arrest and cause apoptosis on several cell tumor lines through extrinsic pathway before intrinsic activation, leading to the caspase-8 Bid stimulation, a pro-apoptotic protein belonging to BCL-2 family that PLEKHM2 also activates mitochondrial pathways ( Liu et al., 2011). This indirectly mitochondrial involvement could explain a longer extensive interval required (48 h) by α-santonin derivatives 2 and 4 to instigate cell damage, which culminates with mitochondrial depolarization and DNA destabilization ( de Thonel and Eriksson, 2005, Liu et al., 2011, Choi et al., 2012 and Guzman and Jordan, 2005). Sesquiterpene lactones have a privileged selectivity for tumor cells (Ghantous et al., 2010). Previously, compounds 2, 3 and 4 were tested against normal cells (PBMC) and showed low toxicity (Arantes et al., 2010). Here, the same ones were tested in alkaline comet assay to analyze their ability to cause DNA alkylation on PBMC. None of compounds were able to DNA disruptions in both concentrations tested (data not shown). Similarly, it was displayed that Parthenolide, another sesquiterpene lactone, selectively kill primitive leukemia cells without affecting normal stem and progenitor hematopoietic cells (Guzman and Jordan, 2005).

e., when not all genotypes can be found in all environments with the same frequency). For simplicity, G*E and covGE are often assumed absent, reducing this to P = G + E. An important statistic derived from this is the heritability, h2 = G/P, which

is often expressed as a percentage. In the same way as the variance, one can attempt the partitioning of the covariance between Alpelisib in vivo two phenotypes x and y. Together with the partitioning of the variance of the two phenotypes, this can give an estimate of the genetic correlation (rG) between these two characters: rG=GxyGxGy. In the absence of a linkage disequilibrium, a significant genetic correlation indicates that there exists one or more genes that influence check details both phenotypes simultaneously, making it highly likely that at least part of the physiological pathways leading from genotype to phenotype are common, so that a causal, and perhaps also functional, relationship must exist between the two phenotypes

[32]. The long history of the field of behavior genetics has greatly enriched our understanding of the inheritance of behavior. New methodologies promise to facilitate gene localization and identification. One serious problem faced by both animal and human behavioral geneticists is the need to increase our understanding of the phenotypes that we study. The behavioral constructs supposedly underlying the test batteries that we use are in urgent need of validation and, in psychiatric genetics, disease entities need to be re-defined. An important role awaits behavior geneticists here, because, if applied judiciously, behavior genetics and its toolbox can aid greatly in this process. Nothing declared. I thank Drs. Richard Brown (Dalhousie University, Halifax, NS, Canada), John Crabbe (VA, Portland, OR, USA), Douglas Wahlsten (Salt Spring Island, BC, Canada), and Frank Peyré (Bordeaux) for many stimulating Ribonucleotide reductase discussions over the years about the ideas presented

in this article. “
“Current Opinion in Behavioural Sciences 2015, 2:xx–yy This review comes from a themed issue on Behavioral Genetics 2015 Edited by William Davies and Laramie Duncan doi:10.1016/j.cobeha.2014.10.011 2352-1546/Published by Elsevier Ltd. Pheromones are chemicals that have evolved as a signal emitted from one individual, to generate a specific reaction in another member of the same species 1 and 2]. Since the landmark purification of bombykol, a compound secreted by female silk moths that provokes males to engage in a frantic wing-fluttering dance, the idea of influencing the behaviour of other individuals via chemicals has captured the public imagination [3]. From a research perspective, provoking behaviour with synthetic chemical cues offers a unique opportunity to experimentally decompose complex social interactions at the sensory, neural, genetic and behavioural level [2].

This anti-inflammatory state leads to immunodepression that could be considered a protective adaptative reaction to suppress the aggressive Th1 response against presented endogenous brain antigens. Therefore, in spite of being learn more beneficial, the enhanced Th2 response might increase the risk of detrimental secondary infections [21,22]. In that context, the modulation of the immune system

by the use of monoclonal antibodies could be of interest in stroke as well as in other diseases with an inflammatory background [reviewed in 23]. Our results showed a very faint power for CCL17 and CCL22 to discriminate those patients who will improve within the first 24–48 h after stroke. Thus, none of these chemokines seem a reliable prognostic biomarker in the hyperacute phase of stroke, when quick decision-making is needed to start a more exhaustive management in order to avoid secondary complications. However, the results of our study might inspire
s of investigation focused on the modulation of CCL17 and/or CCL22 or even CCR4. Our study stands with some limitations. We cannot dismiss the possible presence of some astrocyte end-feet in our vessel samples, since in brain tissue these cell types are tightly interrelated to form the blood–brain-barrier. We cannot dismiss out of hand the fact that the concentration Selleckchem Palbociclib of chemokines in systemic circulation

could contribute to their quantification in LMD-vessels since necropsies might contain traces of blood in vessel lumens. Nevertheless, the undetectable concentration of some of these chemokines in LMD-vessels may suggest a minimal contribution of the circulating levels of each chemokine to its amount in the LMD samples. On the other hand, human brain samples from stroke patients are scarce and thus the small sample size used in this part of the study might affect the results on chemokine levels. Regarding blood samples, we were not able to study the relation between chemokines and neurological outcome in the MISTIC cohort due to the limited number of worsening/improvement

cases. Moreover, the sample size used for the study in the hyperacute phase is relatively small, but the sample size calculations why showed a very large number of samples needed to get significant results for most of the studied chemokines. Further studies are necessary to answer if CCL17 or CCL22 could have a role as outcome biomarkers at a later point in time after hyperacute phase. Other chemokines not included in SearchLight® array might be of interest in stroke field, especially some of them that have not been studied in human stroke (CCL7, CCL9, CXCL2). Novel multiplexed immunoassays based on fluorescently encoded microspheres might increase the screening of circulating inflammatory molecules in stroke patients while using very few amount of sample [24].

Caution is needed in this field not to mislabel normal variation in PEs in the general population as psychiatric illness

[42]. Evidence for or against psychotic illness being on a continuum with PEs does not change the practical need for categorical definitions of psychiatric illness [43]. Vice versa, because there is clinical need for categorical definitions, this Nutlin-3a should not prevent researchers exploring the causes of PEs dimensionally, given that they exist dimensionally in the population (see Figure 1). Another improvement has been research on specific individual PEs, which brings greater clarity to what causes individual experiences such as paranoia, hallucinations, and negative symptoms individually, rather than assuming that PEs form part of a single construct, which is in opposition to empirical psychometric evidence 3, 12, 44 and 45]. Going forward, it is unrealistic

to expect a one-to-one mapping between PEs and schizophrenia, or to find large effect sizes between PEs and schizophrenia, in light Daporinad price of the heterogeneity inherent in the latter. There is much anticipation to understand the origins of PEs as normal aspects of life, particularly in young people, and as predictors of clinically relevant psychopathology. Nothing declared. Papers of particular interest, published within the period of review, have been highlighted as: •• of outstanding interest AR was funded by the Medical Research Council (G1100559). The Bay 11-7085 author would like to thank Professor Daniel Freeman for comments on an earlier version of this manuscript. “
“Current Opinion in Behavioral Sciences 2015, 2:89–95 This review comes from a themed issue on Behavioral genetics Edited by William Davies and Laramie Duncan

http://dx.doi.10.1016/j.cobeha.2014.10.002 2352-1546/© 2014 Published by Elsevier Ltd. All right reserved. Behavior genetics is the study of the inheritance of behavioral phenotypes. Many different species have been studied, especially rodents (mice and rats), fruit flies (Drosophila melanogaster), worms (Caenorhabditis elegans), and humans, with zebrafish (Danio rerio) currently catching up swiftly. Especially in the last few decades, progress has been rapid and many new genetic techniques are helping elucidate the role of genetics in the causation of behavior. Many of these advances will be addressed in the other reviews in this issue. In this review I will focus on a few key issues facing contemporary behavior genetics. Behavior genetics is, in principle, not very different from other subfields of genetics: It is strongly multidisciplinary and interdisciplinary, with contributions from ethology, psychology, neuroscience, ecology, psychiatry, etc., and focuses on a specific class of phenotypes: behavior. Therein, however, also lays its greatest distinction with most other genetics disciplines.

The i.c.v. injection of 4-AP had no effect SB431542 mw on memory, but induced shaking, circling and tonic–clonic seizures at the higher doses tested. In fact, clinical trials have shown that although 4-AP improves cognitive functions in AD patients, the incidence of adverse-effects has hindered its clinical use (Davidson et al., 1988 and Wiseman and Jarvik, 1991). Interestingly, the analysis of amino acid sequence of Tx3-1 shows no relation to other K+ channel blockers (Cordeiro et al., 1993).

The lack of homology with other known blockers of K+ channels could explain the selective pattern of toxin against IA currents, and thus a possible better therapeutic profile when compared to the non-selective Kv blocker 4-AP. In vitro experiments shed light on the involvement of IA currents in AD’s cognitive decline ( Kerrigan et al., 2008, Pan et al., 2004 and Plant et al., 2006). The Aβ peptide, which accumulates in the brain of AD patients ( Fraser et al., 1997; Prince et al., 2009), alters synaptic plasticity ( Holscher RG7204 in vitro et al., 2007 and Cheng et al., 2009), and ion channel function, such as potassium (K+) channels ( Furukawa et al., 1996). Moreover, current evidences suggest a role for Aβ peptides in IA K+ currents regulation ( Kerrigan et al., 2008, Pan

et al., 2004 and Plant et al., 2006). Therefore, we evaluated whether Tx3-1 alter Aβ25-35-induced memory deficits in mice. Administration of Tx3-1, immediately after training session, reversed the Aβ25-35-induced memory impairment. Interestingly, Tx3-1 proved to be more potent in Aβ25-35-treated mice when compared to the control group. One of the causes of this better effect could be attributed to the enhanced expression of cortical and hippocampal IA K+ channels induced by Aβ25-35 ( Pan et al., 2004). The higher potency of Tx3-1 in AD-like conditions makes this toxin a potential prototype for the emergence of more effective therapies

for AD-related cognitive decline. In line with this view, Tx3-1 has been produced through bacterial expression system ( Carneiro et al., 2002). This molecular biological technique is useful to produce not only the recombinant toxin but also to generate mutated versions of the native peptide. Here we reported the memory enhancing effect of Tx3-1, a selective IA blocker, in physiological Farnesyltransferase and AD-like conditions in mice. Despite the data showed here, more experiments, such as electrophysiological techniques, are needed to better elucidate the effect of Tx3-1 on neuronal mechanisms involved in memory storage. This study was supported by Conselho Nacional de Desenvolvimento Científico (CNPq, Brazil – 306164/2010-8, 481664/2010-6, 476551/2009-9), Toxinologia – Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (Capes 2865/2010, 1444/2011), Instituto Nacional de Ciência e Tecnologia (INCT) em Medicina Molecular (MCT/CNPq) and FAPEMIG. We thank CNPq, CAPES and FAPEMIG for the fellowship support.

Ein Mechanismus oder vielmehr eine Folge von Ereignissen zur Erklärung der Selektivität von MeHg sollte außerdem die beobachtete Latenzphase zwischen der Exposition und dem Einsetzen von Symptomen mit einbeziehen. Zunächst einmal ist bekannt, dass das Cerebellum eine große Zahl an Körnerzellen enthält und dass im gesamten

Gehirn ein hoher Grad an Redundanz herrscht. Dies bedeutet, dass das System über einige Reservekapazität verfügt, mit der die erforderliche Leistung des neuronalen Netzwerks aufrechterhalten werden kann. Diese Redundanz hat jedoch Grenzen, und wenn diese erreicht sind, kommt es zu einem Zusammenbruch des Netzwerks. Es dauert einige Zeit, bis das Quecksilber die intrazellulären Verteidigungsmechanismen erschöpft, sogar in kleinen Neuronen, und dies muss in einer this website ausreichenden Anzahl von Neuronen geschehen, bevor das Netzwerk versagt. Ist es jedoch erst einmal so weit, dann entwickeln sich die Symptome sehr schnell. Die Zellspezifität und das verzögerte Einsetzen von Symptomen gehören zu den wichtigen

„Rätseln” im Zusammenhang mit der Neurotoxizität von MeHg. In diesem Übersichtartikel haben wir versucht, die folgenden Hypothesen zu diesen Rätseln Hormones antagonist zu untermauern: • Die Neurotoxizität geht von MeHg selbst aus und nicht von durch Demethylierung gebildetem Hg2+, obwohl Demethylierung im Gehirn stattfindet. Eines der Rätsel jedoch, click here die noch gelöst werden müssen, ist die Dosisunabhängigkeit der Latenzphase vor dem Einsetzen der Symptome. Bei keinem der Autoren besteht ein Interessenkonflikt. Der Erstautor (T. Syversen) möchte sich bei Professor T. W. Clarkson für seine Unterstützung, seine Anregungen und seine Freundschaft in 40 Jahren der Arbeit über die Toxikologie des Quecksilbers und seiner Komponenten bedanken. In der letzten Phase der Vorbereitung dieses Manuskripts hat er wertvolle Vorschläge beigesteuert. “
“The formation of the European Society of Neurosonology and Cerebral Hemodynamics (ESNCH) was proposed by Professor David Russell in a letter to leading European Scientists in this field in

December 1993. In August 1994 Professor Russell sent a more general invitation to European scientists inviting them to attend an inaugural meeting during the 8th International Cerebral Hemodynamics Symposium from 25th to 27th September 1994 which was chaired by Professor E.Bernd Ringelstein in Münster, Germany, from 25th to 27th September 1994. The inaugural meeting of the ESNCH was held on 26th September 1994. The first meeting of the ESNCH was chaired by Professor Jürgen Klingelhöfer and Professor Eva Bartels in Munich, Germany, from 29th August to 1st September 1996. The statutes of the Society were accepted by a General Assembly on 27th May 1997 during the 2nd meeting of the ESNCH in Zeist/Utrecht, Netherlands, which was chaired by Professor Rob G. A. Ackerstaff.

However, maintenance of live colony is costly and sometimes difficult. Cryopreservation of germplasm circumvents the need for maintenance of live colony and genetic material would still be available for future use. In addition, up to now, many inbred mutant and genetically modified rat strains have not been readily available to investigators around the world [1], [28], [31] and [49]. Cryobanking of embryos, sperm, oocytes are becoming

very important both for reducing the maintenance cost and improving distribution of strains [1] and [36]. Cryopreservation of sperm provides a simpler and more economical alternative to cryopreservation of embryos, selleck chemicals llc and reduces the cost and space needed for keeping a large number of rat strains having a single mutation [1] and [35]. Sperm preservation protocols vary among species due to their inherent characteristics. There are marked species differences

in spermatozoa size and morphology. In addition, there are also more subtle differences in membrane phospholipid composition and metabolism of spermatozoa [6]. Rat sperm are known to have extreme sensitivity to suboptimal conditions such as centrifugation, pipetting, chilling, osmotic stress [34], [46] and [51] freezing and thawing [25], [34] and [35] possibly due to unusually long tail, head shape and membrane composition [12], [20] and [24]. Thus, acceptable and repeatable rat sperm cryopreservation protocol has not been achieved [57]. Post-thaw Ganetespib research buy sperm quality is still unsatisfactory for intrauterine insemination Etomidate or in vitro fertilization in rats with genetic modifications [34] and [57]. Despite species variation, there are common stages to any sperm freezing protocol. All protocols involve sperm collection and extension, addition of cryoprotective agents (CPA) and cooling above 0 °C, freezing below 0 °C, storage and thawing [11]. During all of these stages, spermatozoa are exposed a number of potentially damaging stresses such as the change in temperature, osmotic and toxic stresses presented by exposure to high molar concentrations

of CPA and the formation and dissolution of ice crystals in the extracellular space [54]. Success of cryopreservation depends on sperm endurance to these insults [45] and [54]. Extenders, CPA, optimal cooling and thawing rates play important role for successful cryopreservation of sperm [10], [20], [30] and [42]. Extender composition and cooling rate have significant effects on sperm viability and there is a strong interaction between extender and cooling rate [55]. If the cooling rate is slower or faster than optimum cooling rate, this may cause irreversible damage to sperm [13], [27] and [29]. An optimum cooling rate must be slow enough to permit water to leave the cells to avoid intracellular ice formation, and fast enough to avoid severe cell dehydration and cryo-injury due to the solution effect [29].